Method of making filter article having deposit of filter material

Abstract

A method of applying a surface treatment to a stuffed honeycomb body includes atomizing a dispersion of particles of an inorganic material into liquid-particle-dispersant droplets comprising: a liquid vehicle that is one or more solvents other than ethanol or a mixture of water and a solvent; and one or more dispersants. In some embodiments, the liquid vehicle comprises methanol, acetone, hexane, or a combination thereof; the particle dispersant comprises: triethanolamine, a triethoxyvinylsilane, a vinyltrimethoxysilane, a 5-hexenyltrimethoxysilane, or a combination thereof. The particle dispersant comprises: triethanolamine, a triethoxyvinylsilane, a vinyltrimethoxysilane, a 5-hexenyltrimethoxysilane, or a combination thereof. In some embodiments, the liquid vehicle comprises water and a solvent selected from the group consisting of ethanol, methanol, acetone, hexane, or a combination thereof.

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of priority under the Patent Law to U.S. Provisional Application No. 63 / 426,514, filed on November 18, 2022, the content of which is incorporated herein by reference in its entirety and for all purposes. Technical field

[0003] This specification relates to a method for manufacturing a porous body, such as a porous ceramic honeycomb body, suitable for a filter article that includes a filter material deposit composed of aggregates, including inorganic deposits. The method utilizes a mixture formulation that includes a liquid medium and a dispersant, where the liquid medium is one or more solvents other than ethanol, or a mixture of water and a solvent. Background art

[0004] Wall - flow filters are used to remove particulate matter from fluid exhaust streams, such as from the exhaust gases of internal combustion engines. Examples include diesel particulate filters for removing particulate matter from diesel engine exhaust gases and gasoline particulate filters (GPF) for removing particulate matter from gasoline engine exhaust gases. The exhaust gas to be filtered enters an intake unit and passes through the unit walls and exits the filter through outlet channels. When the gas passes through the filter and then exits, the particulate matter is trapped on or inside the unit walls.

[0005] With increasingly strict global automotive exhaust emission regulations, the filtration performance of GPFs needs to be continuously improved in terms of filtration efficiency and pressure drop loss. In addition, there is a continuous need to effectively utilize raw materials and increase process production volume. Summary of the invention

[0006] Aspects of the present disclosure relate to filter articles and methods for their manufacture and use.

[0007] In one aspect, a method of applying a surface treatment to a packed honeycomb body includes: atomizing a dispersion of inorganic material particles into liquid - particle - dispersant droplets, the liquid - particle - dispersant droplets including: a liquid medium that includes methanol, acetone, hexane, or a combination thereof; a particle dispersant that includes triethanolamine, triethoxyvinylsilane, vinyltrimethoxysilane, 5 - hexenyltrimethoxysilane, or a combination thereof; and particles; evaporating at least substantially all of the liquid medium from the droplets to form aggregates of the particles; and depositing the aggregates within the packed honeycomb body; wherein the deposited aggregates are disposed on the porous walls, or within the porous walls, or on and within the porous walls of the honeycomb body that includes a honeycomb structure having a plurality of axial porous walls that define a plurality of axial channels in an axial direction.

[0008] On the other hand, a method for applying a surface treatment to a packed honeycomb body is provided. The honeycomb body includes a honeycomb structure having a plurality of axially porous walls that define a plurality of axial channels in the axial direction. The method includes: atomizing a dispersion of inorganic material particles into liquid-particle-dispersant-binder droplets, the liquid-particle-dispersant-binder droplets consisting essentially of: a liquid medium including methanol, acetone, hexane, or a combination thereof, a particle dispersant, a binder, and particles; evaporating at least substantially all of the liquid medium from the droplets to form an agglomerate of particles; and depositing the agglomerate within the packed honeycomb body; wherein the deposited agglomerate is disposed on the porous walls, or within the porous walls, or both on and within the porous walls.

[0009] In another aspect, a method for applying a surface treatment to a packed honeycomb body includes: atomizing a dispersion of inorganic material particles into liquid-particle-dispersant droplets, the liquid-particle-dispersant droplets including: a liquid medium including water and one or more solvents having a boiling point lower than that of water, a particle dispersant, and particles; evaporating at least substantially all of the liquid medium from the droplets to form an agglomerate of particles; and depositing the agglomerate within the packed honeycomb body; wherein the deposited agglomerate is disposed on the porous walls, or within the porous walls, or both on and within the porous walls, the honeycomb body including a honeycomb structure having a plurality of axially porous walls that define a plurality of axial channels in the axial direction.

[0010] One aspect is a filter article prepared according to any of the methods herein. The filter article includes a filtration efficiency of greater than or equal to 95.0% and a loading of deposited agglomerates of less than or equal to 6 grams per liter of the honeycomb filter body.

[0011] Additional features and advantages will be set forth in the following detailed description, and in part will be apparent to those of ordinary skill in the art from the description, or can be learned by practice of the embodiments described herein, including the following detailed description, the claims, and the drawings.

[0012] It should be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and characteristics of the claimed subject matter. The drawings are included to provide a further understanding of the various embodiments, and the drawings are incorporated in and constitute a part of this specification. The drawings illustrate the various embodiments described herein and, together with the detailed description, are used to explain the principles and operations of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1is a flowchart depicting an exemplary embodiment of a method of forming a filter medium according to an embodiment of the present disclosure;

[0014] Figure 2 schematically depicts an apparatus for depositing a filter medium including an inorganic material according to an embodiment of the present disclosure;

[0015] Figure 3 schematically depicts an apparatus for depositing a filter medium including an inorganic material according to an embodiment of the present disclosure;

[0016] Figure 4 schematically depicts an apparatus for depositing a filter medium including an inorganic material according to an embodiment of the present disclosure;

[0017] Figure 5 schematically depicts an apparatus for depositing a filter medium including an inorganic material according to an embodiment of the present disclosure;

[0018] Figure 6 schematically depicts an apparatus for depositing a filter medium including an inorganic material according to an embodiment of the present disclosure;

[0019] Figure 7 schematically depicts an unfilled honeycomb body;

[0020] Figure 8 schematically depicts a wall flow particulate filter according to an embodiment disclosed and described herein;

[0021] Figure 9 is Figure 12 a longitudinal cross-sectional view of the particulate filter shown in;

[0022] Figure 10 schematically depicts the walls of a honeycomb body loaded with particulates;

[0023] Figure 11 schematically depicts a 2D coating apparatus for depositing a filter medium including an inorganic material according to an embodiment of the present disclosure;

[0024] Figures 12 - 14 provides SEM photographs showing samples prepared according to Example A and Examples 1-2; and

[0025] Figures 15 - 16 provides SEM photographs showing samples prepared according to Example B and Example 3. Detailed Description

[0026] Reference will now be made in detail to embodiments of a filter article and a method for forming a honeycomb body, the honeycomb body comprising a porous honeycomb body, the porous honeycomb body comprising a filter material deposit on, in, or on and in the porous ceramic walls of a honeycomb body substrate, the embodiments of which are shown in the drawings. The deposit comprises the material deposited into the honeycomb body, and compounds that can be formed, for example, by heating one or more of the initially deposited materials. For example, a binder can be converted by heating into an organic component that is ultimately burned off or volatilized, while the inorganic component (such as silica) remains in the honeycomb filter body. Where possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts.

[0027] Definition

[0028] As used in this specification and the appended claims, the singular forms "a", "an", and "the" encompass embodiments having plural referents, unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally used in its sense including "and / or", unless the content clearly dictates otherwise.

[0029] As used herein, "have", "having", "include", "including", "comprise", "comprising", etc. are used in their open-ended sense and generally mean "including but not limited to".

[0030] As mentioned herein, a "honeycomb body" comprises a ceramic honeycomb structure having a substrate with intersecting walls that form cells defining channels. The ceramic honeycomb structure can be formed, extruded, or molded from a plasticized ceramic or from a batch mixture or paste that forms a ceramic. The honeycomb body can comprise an outer wall or skin that is extruded together with the wall substrate or applied after the extrusion of the substrate. For example, the honeycomb body can be a plugged ceramic honeycomb structure that forms a filter body comprising cordierite or other suitable ceramic material. The plugged honeycomb body has one or more channels plugged at one or both ends of the honeycomb body.

[0031] Filter article

[0032] The honeycomb filter body disclosed herein comprises a ceramic honeycomb structure, the ceramic honeycomb structure comprising at least one wall carrying deposits of one or more filter materials, the filter material deposits being configured to filter particulate matter from an air stream. The filter material deposits may be in discrete regions, or in some parts or some embodiments, one or more layers of filter material may be formed at a given location on the walls of the honeycomb body. According to some embodiments, the filter material deposits comprise an inorganic material, in some embodiments, an organic material, and in some embodiments, both an inorganic material and an organic material. For example, in one or more embodiments, the honeycomb body may be formed of cordierite or other porous ceramic material and further comprise filter material deposits disposed on or below the wall surfaces of the cordierite honeycomb structure, including inorganic material deposits.

[0033] In some embodiments, the filter material deposits, including inorganic deposits, comprise one or more of ceramics or refractories. In some embodiments, the filter material deposits comprise an inorganic material to produce inorganic deposits. In some embodiments, the filter material deposits, including inorganic deposits, comprise alumina particles, including alumina nanoparticles, which may be agglomerated and / or aggregated.

[0034] The filter articles herein include a beneficial surface layer microstructure that effectively improves the filtration efficiency (FE) while having a minimal impact on the pressure drop, including effectively meeting the ultra-high FE requirements according to the Euro 7 regulation. The methods herein utilize a mixture formulation that includes a liquid medium and one or more dispersants, the liquid medium being one or more solvents other than ethanol, or a mixture of water and a solvent. In one or more embodiments, the particulate dispersant is selected based on the composition of the liquid medium. In one or more embodiments, the mixture formulation does not include an adhesion promoter. In one or more embodiments, the mixture formulation consists essentially of or consists of: a liquid medium, which is a non-ethanol solvent or a mixture of water and an organic solvent; a particulate dispersant, particulates, and optionally a binder. In one or more embodiments, the mixture formulation consists essentially of or consists of: a liquid medium, which comprises methanol, acetone, hexane, or a combination thereof; a particulate dispersant, and particulates. In one or more embodiments, the mixture formulation consists essentially of or consists of: a liquid medium, which comprises methanol, acetone, hexane, or a combination thereof; a particulate dispersant, a binder, and particulates.

[0035] The mixture formulations herein help to reduce the coating loading requirements for preparing filter articles, which in turn provides the following advantages: (1) reducing the use of raw materials, and (2) accelerating the manufacturing time.

[0036] Relative to a method that uses only ethanol as a liquid medium when atomizing a dispersion of inorganic material particles into droplets, one or more non-ethanol organic solvents having a lower surface tension or viscosity and / or a lower boiling point relative to ethanol are used to form smaller spray droplets and the resulting aggregates. Without wishing to be bound by theory, the size of the sprayed droplets is smaller due to the lower surface tension, and the use of a solvent with a lower boiling point results in faster evaporation of the droplets, which hinders particle agglomeration and growth. The smaller the aggregate size, the lower the loading requirement to achieve the desired filtration efficiency (FE). In one or more embodiments, for a given set of additional operating conditions, the volume-based average particle diameter (D 50 ) of the aggregates produced using one or more non-ethanol organic solvents having a lower surface tension or viscosity and / or a lower boiling point relative to ethanol is less than the volume-based average particle diameter of the aggregates produced using only ethanol. In one or more embodiments, for a given set of additional operating conditions, the median particle size (D 50 ) of the aggregates produced using one or more non-ethanol organic solvents having a lower surface tension or viscosity and / or a lower boiling point relative to ethanol is less than the median particle size of the aggregates produced using only ethanol. In one or more embodiments, the aggregates have a volume-based average particle diameter (D 50 ) in the range greater than or equal to 0.5 microns to less than or equal to 0.95 microns, including all values and sub-ranges therebetween. For a given set of operating conditions, the aggregates produced using only ethanol are considered comparative aggregates, which have a comparative volume-based average particle diameter (D 50 ) or a comparative volume-based average particle diameter (D 50 ).

[0037] Similarly, relative to a method that uses only water as a liquid medium when atomizing a dispersion of inorganic material particles into droplets, smaller spray droplets and the resulting aggregates are formed by mixing water with one or more organic solvents having a lower surface tension or viscosity and / or a lower boiling point relative to water. In one or more embodiments, for a given set of additional operating conditions, the volume-based average particle diameter (D 50) is less than the volume-based average particle diameter of the aggregates produced using only water. In one or more embodiments, for a given set of operating conditions, the volume-based average particle diameter (D 50 ) of the aggregates produced using a mixture of water and one or more organic solvents having a lower surface tension or viscosity and / or a lower boiling point relative to water is less than the volume-based average particle diameter of the aggregates produced using only water. In one or more embodiments, it is in the range of greater than or equal to 0.5 micrometers to less than or equal to 0.97 micrometers, including all values and sub-ranges therebetween. For a given set of operating conditions, the aggregates produced using only water are considered comparative aggregates having a comparative volume-based average particle diameter (D 50 ) or a comparative volume-based average particle diameter (D 50 ).

[0038] Method

[0039] Aspects of the present disclosure relate to methods of forming porous bodies, such as porous ceramic honeycombs, that include materials, such as filter materials, such as inorganic materials, such as ceramics or refractories, or even porous ceramics or refractories. In a specific embodiment, the filter material is an aerosol-deposited filter material. In some preferred embodiments, the filter material includes a plurality of inorganic particle aggregates, where the aggregates are composed of an inorganic material, such as a ceramic or refractory. In some embodiments, the aggregates are porous, which may allow gas to flow through the aggregates.

[0040] Aerosol deposition enables the filter material to be deposited onto the porous ceramic walls, which can be as small as a single aggregate or larger, such as discrete regions of multiple aggregates, and in some embodiments, in the form of a porous layer of the filter material on at least some surfaces of the walls of the ceramic honeycomb or within at least some surfaces of the walls, or on at least some surfaces of the walls of the ceramic honeycomb and within at least some surfaces of the walls. In certain embodiments, the advantages of the aerosol deposition method according to one or more embodiments are that ceramic honeycombs with enhanced filtration performance can be produced economically and / or more efficiently.

[0041] In certain embodiments, the aerosol deposition methods disclosed herein include: preparing a mixture (e.g., inorganic material particles, a liquid medium, and a binder); atomizing the mixture with an atomizing gas using a nozzle to form agglomerates and / or aggregates, the agglomerates and / or aggregates comprising inorganic material, a liquid medium, and a binder; drying the agglomerates and / or aggregates in the presence of a carrier gas or gaseous carrier stream; depositing the aggregates and / or agglomerates onto a honeycomb body; and optionally curing the material. In some embodiments, the walls of the device can be heated to assist in drying the aggregates and / or agglomerates.

[0042] According to one or more embodiments, as Figure 1 shown, method 400 includes the following operations: preparing a mixture 405; atomizing to form droplets 410; mixing the droplets with a gaseous carrier stream 415; evaporating the liquid medium to form agglomerates 420; depositing the material, such as the agglomerates, on the walls of a wall-flow filter 425; and optional post-treatment 430 to, for example, bond the material to the porous walls of the honeycomb body, or within the porous walls of the honeycomb body, or on and within the porous walls of the honeycomb body.

[0043] In Figure 1 the method, aerosol deposition forms a filter material deposit, including an inorganic material deposit, which in some specific embodiments is a porous material deposit. In some embodiments, the material deposit is in the form of discrete regions of the filter material. In some embodiments, at least some portions of the material deposit can be in the form of a porous inorganic layer.

[0044] In various embodiments, the method further includes component switching to deposit the agglomerates semi - continuously or continuously onto the porous walls of the plugged honeycomb body, which reduces the idle time of the equipment. In one or more embodiments, the component switching is timed such that deposition occurs substantially continuously onto and / or onto a plurality of ceramic honeycomb bodies. By continuous is meant that the operating equipment is maintained at operating temperature and pressure and under a raw material supply flow, and the process of the gaseous carrier flow and the agglomerate flow to a component such as a wall - flow filter is interrupted only when switching the loaded component to an unloaded component. Semi - continuous also allows for minor interruptions in the raw material supply flow and adjustments to the operating temperature and pressure. In one or more embodiments, semi - continuous flow means that the time of flow interruption is greater than or equal to 0.1% to less than or equal to 5% of the operating duration, including greater than or equal to 0.5%, greater than or equal to 1%, greater than or equal to 1.5%, greater than or equal to 2%, greater than or equal to 2.5% and / or less than or equal to 4.5%, less than or equal to 4%, less than or equal to 3.5%, less than or equal to 3%. In one or more embodiments, the time of continuous flow is greater than or equal to 95% to less than or equal to 100% of the operating duration, including greater than or equal to 96%, greater than or equal to 97%, greater than or equal to 98%, greater than or equal to 99%, greater than or equal to 99.5% and / or less than or equal to 99.9%, less than or equal to 99%, less than or equal to 98%, less than or equal to 97%.

[0045] Prepare mixture 405.

[0046] Commercially available inorganic particles can be used as raw materials in the mixture for forming the inorganic material to be deposited. According to one or more embodiments, the particles are selected from Al2O3, SiO2, TiO2, CeO2, ZrO2, SiC, MgO, and combinations thereof. In one or more embodiments, the mixture is a suspension. The particles can be provided as a raw material suspended in a liquid medium.

[0047] Liquid medium: one or more non - ethanol organic solvents. In some embodiments, the mixture formulation, including the suspension, is organic - based and contains a liquid medium containing one or more non - ethanol organic solvents. In one or more embodiments, the non - ethanol organic solvent includes an organic solvent having a lower surface tension or viscosity and / or a lower boiling point relative to ethanol. In one or more embodiments, the liquid medium contains methanol, acetone, hexane, or a combination thereof. In one or more embodiments, the liquid medium consists essentially of methanol, acetone, hexane, or a combination thereof. In one or more embodiments, the liquid medium consists of methanol, acetone, hexane, or a combination thereof.

[0048] Liquid medium: Water is mixed with one or more organic solvents that have a lower surface tension or viscosity and / or a lower boiling point relative to water. In some embodiments, the mixture formulation, including the suspension, contains a liquid medium that is a mixture of water and one or more organic solvents that have a lower surface tension or viscosity and / or a lower boiling point relative to water. In one or more embodiments, the liquid medium comprises: water, and one or more solvents selected from the group consisting of ethanol, methanol, acetone, hexane, or combinations thereof. In one or more embodiments, the liquid medium consists essentially of: water, and one or more solvents selected from the group consisting of ethanol, methanol, acetone, hexane, or combinations thereof. In one or more embodiments, the liquid medium consists of: water, and one or more solvents selected from the group consisting of ethanol, methanol, acetone, hexane, or combinations thereof.

[0049] Particle dispersant. The particle dispersant can have one or both of the following properties: (1) capable of changing the surface charge on the particles (i.e., alumina particles) to minimize and / or avoid any agglomeration in the mixture formulation / suspension; and / or (2) having two types of functional groups, where one functional group helps the dispersant attach to the particles, including alumina particles, and the other functional group promotes the miscibility of the dispersant with the solvent. In one or more embodiments, the mixture formulation, including the suspension, further contains a particle dispersant. In one or more embodiments, the particle dispersant comprises: triethanolamine, triethoxyvinylsilane, vinyltrimethoxysilane, 5-hexenyltrimethoxysilane, or combinations thereof. In one or more embodiments, when the liquid medium contains methanol, the particle dispersant comprises triethanolamine. In one or more embodiments, when the liquid medium contains acetone, the particle dispersant comprises triethoxyvinylsilane or vinyltrimethoxysilane. In one or more embodiments, when the liquid medium contains hexane, the particle dispersant comprises 5-hexenyltrimethoxysilane. In one or more embodiments, when the liquid medium contains water and an organic solvent, the particle dispersant comprises acetic acid, triethanolamine, triethoxyvinylsilane, vinyltrimethoxysilane, and / or 5-hexenyltrimethoxysilane. In some embodiments, Troysperse from Troy Corporation is a surfactant and modified fatty acid and is a suitable particle dispersant.

[0050] Adhesion promoter. In one or more embodiments, the mixture formulation, including the suspension, does not include an adhesion promoter. The mention of "adhesion promoter" refers to a component that exhibits one or more properties of epoxy reactivity and methoxysilyl inorganic reactivity. In one or more embodiments, the mixture formulation, including the suspension, does not include materials from the group consisting of: (γ-glycidoxypropyl)trimethoxysilane, (3-glycidoxybutyl)trimethoxysilane, (3-glycidoxyethyl)trimethoxysilane, and 3-glycidoxyhexadecyltrimethoxysilane.

[0051] In some embodiments, the suspension comprises, by weight: 5% - 20% particles, 0.1% to 5% particle dispersant, and 80% - 95% liquid medium, and all values and subranges in between. In one embodiment, the suspension comprises, by weight: 11% ± 1% alumina, 2% ± 0.5% particle dispersant, and 87% ± 1% liquid medium.

[0052] In one or more embodiments, the average primary particle size of the particles is in the range of about 10 nm to about 4 μm, about 20 nm to about 3 μm, or about 50 nm to about 2 μm, or about 50 nm to about 900 nm, or about 50 nm to about 600 nm. In a specific embodiment, the average primary particle size is in the range of about 100 nm to about 200 nm, for example, 150 nm. The average primary particle size can be determined as the value calculated according to the Brunauer, Emmett, and Teller (BET) surface area of the aerosol particles. In some embodiments, it is greater than or equal to 7.0 m 2 / g and less than or equal to 30 m 2 / g, including all values and ranges therebetween, including 9 m 2 / g.

[0053] In one or more embodiments, the primary particles comprise ceramic particles, such as oxide particles, such as Al2O3, SiO2, MgO, CeO2, ZrO2, CaO, TiO2, cordierite, mullite, SiC, aluminum titanate, and mixtures thereof.

[0054] If desired, an additional amount of liquid (e.g., diluent) can be added to the mixture to dilute the suspension. In one or more embodiments, the additional liquid is the same as the liquid medium. If the droplets generated by atomization have similar sizes, reducing the solid content in the mixture may proportionally reduce the aggregate size. The diluent should be miscible with the above suspension and can effectively dissolve and / or disperse the binder and other components.

[0055] Binder. A binder may be optionally added to strengthen the agglomerates and provide adhesiveness or tack, and the binder may include an inorganic binder to provide mechanical integrity to the deposited material. In some embodiments, the binder may provide bonding strength between the particles at high temperatures (>500 °C). The starting material may be organic. After exposure to high temperatures above about 150 °C, the organic starting material will decompose or react with moisture and oxygen in the air, and the final deposited material composition may include Al2O3, SiO2, MgO, CeO2, ZrO2, CaO, TiO2, cordierite, mullite, SiC, aluminum titanate, and mixtures thereof.

[0056] In one or more embodiments, the binder is a silicon-containing compound. In one or more embodiments, the silicon-containing compound consists of siloxane or polysiloxane, silicone, silicate, or a combination thereof. In one or more embodiments, the silicon-containing compound consists of silicone compounds, polysiloxanes, silicone resins, siloxanes, alkoxysiloxanes, or a combination thereof. In one or more embodiments, the silicon-containing compound consists of silicate, alkaline silicate, sodium silicate, or a combination thereof.

[0057] A catalyst may be added to accelerate the curing reaction of the binder. An exemplary catalyst content is 1 wt% of the binder.

[0058] Stirring of the mixture or suspension during storage and / or while waiting to be delivered to the nozzle may be carried out by using a desired stirring technique. In one or more embodiments, stirring is carried out by a mechanical stirrer. In one embodiment, the use of a mechanical stirrer helps to reduce and / or eliminate contamination that may be caused by the plastic-coated mixing rod used in the magnetic stirring system for contact with the containment vessel.

[0059] Atomization to form droplets 410. High-pressure gas atomizes the mixture into fine droplets through the nozzle. The setup consists of a nozzle body as well as a fluid cap and an air cap. The atomizing gas may help break up the liquid-particle-binder stream into droplets.

[0060] In one or more embodiments, the nozzles herein are internally mixed nozzles. In one or more embodiments, the nozzles herein are externally mixed nozzles. Externally mixed nozzles are conducive to achieving smaller particle sizes and a tighter particle size distribution, thereby improving material utilization and filtration efficiency. Compared with internally mixed nozzles, externally mixed nozzles tend to be less frequently blocked. In one or more embodiments, the nozzles herein are convergent nozzles. As used herein, a convergent nozzle refers to a nozzle having a fluid flow channel whose cross-sectional area decreases from the inlet to the outlet, thereby accelerating the flow of the fluid. The convergent nozzle may be internally mixed or externally mixed. In one or more embodiments, the liquid-particle-binder droplets are guided through the nozzle into a chamber.

[0061] In one or more embodiments, liquid-particle-binder droplets are directed into a chamber through a plurality of nozzles. In one or more embodiments, atomizing a plurality of liquid-particle-binder streams is performed with a plurality of atomizing nozzles. The plurality of nozzles can include 2 or more nozzles, 3 or more nozzles, 4 or more nozzles, 5 or more nozzles, 6 or more nozzles, 7 or more nozzles, 8 or more nozzles, 9 or more nozzles, 10 or more nozzles, and the like. The plurality of nozzles can be evenly spaced within the chamber. In one or more embodiments, each of the plurality of nozzles is angled towards the center of the device. The angle of the nozzle can be an acute angle, in the range of less than 90° to greater than 10° relative to the sidewall of the device, and all values and sub-ranges therebetween, including 20° to 45°.

[0062] The pressure of the atomizing gas can be in the range of 20 psi to 230 psi. The pressure of the liquid can be in the range of 1 to 100 psi. According to one or more embodiments, the average droplet size can be in the range of 1 μm to 40 μm, including, for example, in the following ranges: greater than or equal to 1 μm to less than or equal to 15 μm; greater than or equal to 2 μm to less than or equal to 8 μm; greater than or equal to 4 μm to less than or equal to 8 μm; and greater than or equal to 4 μm to less than or equal to 6 μm; and all values and sub-ranges therebetween. The droplet size can be adjusted by adjusting the surface tension of the mixture, the viscosity of the mixture, the density of the mixture, the gas flow rate, the gas pressure, the liquid flow rate, the liquid pressure, and the nozzle design. In one or more embodiments, the atomizing gas comprises nitrogen. In one or more embodiments, the atomizing gas can consist essentially of an inert gas. In one or more embodiments, the atomizing gas can be predominantly one or more inert gases. In one or more embodiments, the atomizing gas can be predominantly nitrogen. In one or more embodiments, the atomizing gas can be predominantly air. In one or more embodiments, the atomizing gas can consist essentially of nitrogen or air. In one or more embodiments, the atomizing gas can be dry. In one or more embodiments, the atomizing gas can be substantially free of liquid medium when entering the chamber.

[0063] In some embodiments, the suspension flow rate is in the range of 10 to 80 grams per minute, including all values and sub-ranges therebetween, including 18 grams per minute. In some embodiments, the atomizing gas flow rate and the nitrogen gas flow rate are in the range of 2 to 20 Nm 3 / hr, including all values and sub-ranges therebetween, including 5-6 Nm 3 / hr.

[0064] The flow rate of the suspension and the corresponding aggregate size can be controlled by a pressure control system or a flow control system, depending on the equipment. For a pressure control system, a pressure controller is in communication with a delivery conduit (e.g., a tube or pipe line), and a suspension of primary particles in a liquid is introduced into the delivery conduit and then flows to a nozzle. For a flow control system, an injection pump is provided that delivers a suspension of primary particles in a liquid to the nozzle. The atomizing gas is typically supplied separately to the nozzle. In a preferred embodiment, the pump directs a liquid-particle-binder mixture to the atomizing nozzle at a substantially constant flow rate. A constant flow rate may be more advantageous compared to maintaining a constant pressure because a constant flow rate can help reduce the variability of the particle size, thereby improving material utilization.

[0065] In one or more embodiments, the suspension comprises an inorganic material, a liquid medium, and a particulate dispersant and is supplied to the nozzle in the form of a liquid-particle-dispersant stream. That is, the inorganic material particles can be mixed with the liquid medium and the particulate dispersant to form a liquid-particle-dispersant stream. The liquid-particle-dispersant stream is atomized into liquid-particle-dispersant droplets by the atomizing gas through the nozzle. In one or more embodiments, the liquid-particle-dispersant stream is mixed with the atomizing gas. In one or more embodiments, the liquid-particle-dispersant stream is directed into the atomizing nozzle to atomize the particles into liquid-particle-dispersant droplets. The liquid-particle-dispersant droplets are composed of the liquid medium, the particulate dispersant, and the particles.

[0066] In one or more embodiments, the liquid-particle-dispersant stream is mixed with the atomizing gas through the atomizing nozzle. In one or more embodiments, the liquid-particle-dispersant stream enters the atomizing nozzle. In one or more embodiments, the mixing of the liquid-particle-dispersant stream and the atomizing gas occurs inside the atomizing nozzle. In one or more embodiments, the mixing of the liquid-particle-dispersant stream and the atomizing gas occurs outside the atomizing nozzle.

[0067] In one or more embodiments, the suspension comprises an inorganic material, a liquid medium, a particulate dispersant, and a binder and is supplied to the nozzle in the form of a liquid-particle-dispersant-binder stream. That is, the inorganic material particles can be mixed with the liquid medium, the particulate dispersant, and the binder to form a liquid-particle-dispersant-binder stream. The liquid-particle-dispersant-binder stream is atomized into liquid-particle-dispersant-binder droplets by the atomizing gas through the nozzle. In one or more embodiments, the liquid-particle-dispersant-binder stream is mixed with the atomizing gas. In one or more embodiments, the liquid-particle-dispersant-binder stream is directed into the atomizing nozzle to atomize the particles into liquid-particle-dispersant-binder droplets. The liquid-particle-dispersant-binder droplets are composed of the liquid medium, the particulate dispersant, the binder, and the particles.

[0068] In one or more embodiments, a liquid-particle-dispersant-binder stream is mixed with an atomizing gas through an atomizing nozzle. In one or more embodiments, the liquid-particle-dispersant-binder stream enters the atomizing nozzle. In one or more embodiments, the mixing of the liquid-particle-dispersant-binder stream and the atomizing gas occurs inside the atomizing nozzle. In one or more embodiments, the mixing of the liquid-particle-dispersant-binder stream and the atomizing gas occurs outside the atomizing nozzle.

[0069] The liquid droplets and the gaseous carrier stream are mixed 415. The liquid droplets are transported to the honeycomb body by the gaseous carrier stream. In one or more embodiments, the gaseous carrier stream comprises a carrier gas and an atomizing gas. In one or more embodiments, at least a portion of the carrier gas contacts the atomizing nozzle. In one or more embodiments, substantially all of the liquid medium is evaporated from the liquid droplets to form agglomerates composed of particles and a binder.

[0070] In one or more embodiments, the gaseous carrier stream is heated prior to mixing with the liquid droplets. In one or more embodiments, the temperature of the gaseous carrier stream is in the range of greater than or equal to 50 °C to less than or equal to 500 °C, including all of greater than or equal to 80 °C to less than or equal to 300 °C, greater than or equal to 50 °C to less than or equal to 150 °C, and all values and sub-ranges therebetween. Without being bound by theory, it is believed that the advantage of a higher temperature is that the liquid droplets evaporate more quickly, and when a large amount of liquid evaporates, they are less likely to stick together when they collide. In certain embodiments, smaller agglomerates contribute to better formation of the filter media deposit. Additionally, it is believed that if the liquid droplets collide but contain only a small amount of liquid (e.g., only internally), the liquid droplets may not coalesce into a spherical shape. In some embodiments, non-spherical agglomerates can provide the desired filtration performance.

[0071] In one or more embodiments, the atomizing gas is heated to form a heated atomizing gas and then passed through and / or contacted with the nozzle. In one or more embodiments, the temperature of the heated atomizing gas is in the range of greater than or equal to 50 °C to less than or equal to 500 °C, including all of greater than or equal to 80 °C to less than or equal to 300 °C, greater than or equal to 50 °C to less than or equal to 150 °C, and all values and sub-ranges therebetween.

[0072] In one or more embodiments, both the carrier gas and the atomizing gas are independently heated and contacted with the nozzle. In one or more embodiments, the gaseous vapor is heated, but the atomizing gas and the nozzle are maintained at a low temperature (about equal to room temperature, e.g., 25 - 40 °C). In one or more embodiments, the atomizing nozzle is cooled during atomization. In one or more embodiments, the temperature of the atomizing nozzle is maintained below the boiling point of the liquid medium.

[0073] A carrier gas is supplied to the device to facilitate drying of the liquid-particle-binder droplets and to carry the liquid-particle-binder droplets and the resulting agglomerates through the device and into the honeycomb body. In one or more embodiments, the carrier gas is primarily an inert gas, such as nitrogen. In one or more embodiments, the carrier gas consists essentially of an inert gas. In one or more embodiments, the carrier gas is primarily one or more inert gases. In one or more embodiments, the carrier gas is primarily nitrogen. In one or more embodiments, the carrier gas is primarily air. In one or more embodiments, the carrier gas consists essentially of nitrogen or air. In one or more embodiments, the carrier gas is dry. In one or more embodiments, the carrier gas contains substantially no liquid medium when entering the chamber. In one or more embodiments, the carrier gas contains less than 5 wt% water vapor. In one or more embodiments, the carrier gas is heated before being mixed with the droplets. In one or more embodiments, the temperature of the carrier gas is in the range of greater than or equal to 50 °C to less than or equal to 500 °C, including all of greater than or equal to 80 °C to less than or equal to 300 °C, greater than or equal to 50 °C to less than or equal to 150 °C, and all values and sub-ranges therebetween.

[0074] In one or more embodiments, the atomizing gas and the carrier gas are independently delivered to the device at a pressure of greater than or equal to 90 psi, including greater than or equal to 95 psi, greater than or equal to 100 psi, greater than or equal to 105 psi, greater than or equal to 100 psi, greater than or equal to 115 psi, or greater than or equal to 120 psi. In one or more embodiments, a booster provides the atomizing gas and the carrier gas at the desired pressure. The device may include a diffusion region downstream of the nozzle. At least some mixing of the gaseous carrier stream with the liquid-particle-binder droplets occurs in the diffusion region.

[0075] When the gaseous carrier stream is mixed with the liquid-particle-binder droplets in the chamber, a gas-liquid-particle-binder mixture is formed. The gas-liquid-particle-binder mixture is heated in the mixing zone. In one or more embodiments, droplets of a liquid containing particles and binder are present during mixing. In one or more embodiments, the gaseous carrier stream is heated before being mixed with the liquid-particle-binder droplets.

[0076] In one embodiment, the carrier gas is delivered to the chamber in an annular co-flow around the nozzle. In one embodiment, the carrier gas is delivered to the chamber of the duct in an annular flow around the nozzle in a co-flow around the droplets at the end of the nozzle.

[0077] Evaporation occurs to form the agglomerates 420.

[0078] To avoid the formation of non-uniform materials due to the influence of liquid capillary forces, which can lead to high pressure drop losses, the droplets are dried in the evaporation section of the device to form dry solid agglomerates, which can be referred to as secondary particles or "micro-particles" made of primary nanoparticles and binder-type materials. The liquid medium or solvent evaporates and passes through the honeycomb body in the gas phase or vapor phase, thus minimizing the residue or condensation of the liquid solvent during material deposition. When the agglomerates are carried into the honeycomb body by the gas flow, the residual liquid in the inorganic material should be less than 10 wt%. In some embodiments, all the liquid evaporates due to drying and is converted into the gas phase or vapor phase. In some embodiments, the liquid residue includes the solvent in the mixture, such as water condensed from the gas phase. Even if some or all of the binder may be in a liquid or other non-solid state before curing, the binder is not considered a liquid residue. In one or more embodiments, the total volume flow rate through the chamber is greater than or equal to 5 Nm 3 / hr and / or less than or equal to 200 Nm 3 / hr; including greater than or equal to 20 Nm 3 / hr and / or less than or equal to 100 Nm 3 / hr; and all values and sub-ranges therebetween. Higher flow rates can deposit more material than lower flow rates. When filters with a larger cross-sectional area are to be produced, higher flow rates will be useful. Filters with a larger cross-sectional area can be applied in building filtration systems or outdoor filtration systems.

[0079] In one or more embodiments, substantially all of the liquid medium is evaporated from the droplets to form agglomerates of particles and binder, and the agglomerates are dispersed in the gaseous carrier stream. In one or more embodiments, the device has an evaporation section, and the axial length of the evaporation section is sufficient to allow at least a portion of the liquid medium to evaporate from the agglomerates, including the vast majority and / or all of the liquid medium.

[0080] Regarding the flow, in one embodiment, the path of the droplets and the path of the gaseous carrier stream are substantially perpendicular before entering the evaporation section. In one or more embodiments, the carrier gas contacts the atomizing nozzle by means of a first path, and the path of the droplets and the second path of the carrier gas are substantially perpendicular to each other before entering the evaporation section of the duct.

[0081] In another embodiment, the path of the droplets and the path of the gaseous carrier stream are substantially parallel after entering the evaporation section. In one or more embodiments, the path of the droplets and the path of the gaseous carrier stream are substantially parallel to each other after entering the evaporation section of the duct. In one or more embodiments, the path of the droplets and the path of the carrier gas are substantially parallel to each other after entering the evaporation section of the duct.

[0082] In one embodiment, the gaseous carrier stream exits the chamber in a direction substantially parallel to gravity. In one embodiment, the gaseous carrier stream exits the chamber in a substantially downward direction. In one embodiment, the gaseous carrier stream exits the chamber in a substantially upward direction.

[0083] Deposition in the honeycomb body 425. Secondary particles or aggregates of primary particles are carried in the gas stream, and when the gas passes through the honeycomb body, the secondary particles or aggregates and / or their aggregates are deposited on the inlet wall surface of the honeycomb body. In one or more embodiments, the aggregates and / or their aggregates are deposited on the porous walls of the plugged honeycomb body. The deposited aggregates can be disposed on the porous walls, or in the porous walls, or on and in the porous walls. In one or more embodiments, the plugged honeycomb body includes inlet channels plugged at the distal end of the honeycomb body and outlet channels plugged at the proximal end of the honeycomb body. In one or more embodiments, the aggregates and / or their aggregates are deposited on the walls defining the inlet channels, or in the walls, or on and in the walls. The flow can be driven by a fan, a blower, or a vacuum pump. Additional air can be drawn into the system to achieve the desired flow rate. The desired flow rate is in the range of 5 to 200 m 3 / hr. An exemplary honeycomb body is suitable for use as a gasoline particulate filter (GPF) and has the following non-limiting characteristics: a diameter of 4.055 inches (10.3 cm), a length of 5.47 inches (13.9 cm), 200 cells per square inch (CPSI), a wall thickness of 8 mils (203 μm), and a median pore size in the body of 14 μm.

[0084] In one or more embodiments, the average diameter of the secondary particles or aggregates is in the range of 300 nm μm to 10 μm, 300 nm to 8 μm, 300 nm μm to 7 μm, 300 nm μm to 6 μm, 300 nm μm to 5 μm, 300 nm μm to 4 μm, or 300 nm μm to 3 μm. In a specific embodiment, the average diameter of the secondary particles or aggregates is in the range of 1.5 μm to 3 μm, including about 2 μm. The average diameter of the secondary particles or aggregates can be measured by scanning electron microscopy.

[0085] It should be noted that there seems to be a typo in the original text where "300nmμm" is likely incorrect. It is translated as presented but might need to be corrected in the original for more accurate technical understanding.In one or more embodiments, the average diameter of the secondary particles or agglomerates is in the range of 300 nm to 10 μm, 300 nm to 8 μm, 300 nm to 7 μm, 300 nm to 6 μm, 300 nm to 5 μm, 300 nm to 4 μm, or 300 nm to 3 μm, including the range of 1.5 μm to 3 μm, and including about 2 μm, and the ratio of the average diameter of the secondary particles or agglomerates to the average diameter of the primary particles is in the following ranges: about 2:1 to about 67:1; about 2:1 to about 9:1; about 2:1 to about 8:1; about 2:1 to about 7:1; about 2:1 to about 6:1; about 2:1 to about 5:1; about 3:1 to about 10:1; about 3:1 to about 9:1; about 3:1 to about 8:1; about 3:1 to about 7:1; about 3:1 to about 6:1; about 3:1 to about 5:1; about 4:1 to about 10:1; about 4:1 to about 9:1; about 4:1 to about 8:1; about 4:1 to about 7:1; about 4:1 to about 6:1; about 4:1 to about 5:1; about 5:1 to about 10:1; about 5:1 to about 9:1; about 5:1 to about 8:1; about 5:1 to about 7:1; or about 5:1 to about 6:1, and including about 10:1 to about 20:1.

[0086] In one or more embodiments, depositing the agglomerates onto the porous wall further comprises passing a gaseous carrier stream through the porous wall of the honeycomb body, wherein the walls of the honeycomb body filter out at least some of the agglomerates by trapping the filtered agglomerates on or in the walls of the honeycomb body. In one or more embodiments, depositing the agglomerates on the porous wall comprises filtering the agglomerates from the gaseous carrier stream with the porous wall of the packed honeycomb body.

[0087] Post-treatment 430. Optionally, post-treatment can be used to adhere the agglomerates to the honeycomb body and / or to each other. That is, in one or more embodiments, at least some of the agglomerates adhere to the porous wall. In one or more embodiments, the post-treatment comprises heating and / or curing the binder according to one or more embodiments. In one or more embodiments, the binder causes the agglomerates to adhere or stick to the walls of the honeycomb body. In one or more embodiments, the binder bonds the agglomerates.

[0088] Depending on the composition of the binder, the curing conditions can vary. According to some embodiments, a low-temperature curing reaction is utilized, such as a temperature ≤ 100°C. In some embodiments, the curing can be completed in an automotive exhaust gas at a temperature ≤ 950°C. The calcination treatment is optional and can be carried out at a temperature ≤ 650°C. Exemplary curing conditions are: a temperature range of 40°C to 200°C for 10 minutes to 48 hours.

[0089] In one or more embodiments, the agglomerates and / or their aggregates are heated after being deposited on the honeycomb body. In one or more embodiments, heating of the agglomerates causes the organic components of the binder to be removed from the deposited agglomerates. In one or more embodiments, heating of the agglomerates causes the inorganic components of the binder to physically bond the agglomerates to the walls of the honeycomb body. In one or more embodiments, heating of the agglomerates causes the inorganic components of the binder to form a porous inorganic structure on the porous walls of the honeycomb body. In one or more embodiments, heating of the deposited agglomerates burns off or volatilizes the organic components of the binder in the deposited agglomerates.

[0090] In one aspect, a method of applying a surface treatment to a loaded honeycomb body comprises: atomizing a dispersion of inorganic material particles into liquid-particle-dispersant droplets, the liquid-particle-dispersant droplets comprising: a liquid medium comprising methanol, acetone, hexane, or a combination thereof; a particle dispersant comprising triethanolamine, triethoxyvinylsilane, vinyltrimethoxysilane, 5-hexenyltrimethoxysilane, or a combination thereof; and particles; evaporating at least substantially all of the liquid medium from the droplets to form agglomerates of the particles; and depositing the agglomerates within the loaded honeycomb body; wherein the deposited agglomerates are disposed on the porous walls, or within the porous walls, or on and within the porous walls, the honeycomb body comprising a honeycomb structure having a plurality of axial porous walls that define a plurality of axial channels in an axial direction.

[0091] In one or more embodiments, the method further comprises atomizing a binder with the dispersion such that the droplets are liquid-particle-dispersant-binder droplets and the agglomerates further comprise the binder. In one or more embodiments, the atomizing further comprises supplying a suspension of the particles, the liquid medium, and the particle dispersant.

[0092] In one or more embodiments, when the liquid medium comprises methanol, the particle dispersant comprises triethanolamine; or when the liquid medium comprises acetone, the particle dispersant comprises triethoxyvinylsilane or vinyltrimethoxysilane; or when the liquid medium comprises hexane, the particle dispersant comprises 5-hexenyltrimethoxysilane.

[0093] In one or more embodiments, for a given set of operating conditions, the volume-based average particle size (D 50 ) of the agglomerates is less than the comparative volume-based average particle size (D 50 ) of comparative agglomerates formed by a method using the given set of operating conditions but using ethanol as the liquid medium.

[0094] On the other hand, there is provided a method of applying a surface treatment to a packed honeycomb body, the honeycomb body comprising a honeycomb structure having a plurality of axially porous walls that define a plurality of axial channels in the axial direction, the method comprising: atomizing a dispersion of inorganic material particles into liquid-particle-dispersant-binder droplets, the liquid-particle-dispersant-binder droplets consisting essentially of: a liquid medium comprising methanol, acetone, hexane, or a combination thereof, a particle dispersant, a binder, and particles; evaporating at least substantially all of the liquid medium from the droplets to form aggregates of the particles; and depositing the aggregates within the packed honeycomb body; wherein the deposited aggregates are disposed on the porous walls, or within the porous walls, or both on and within the porous walls.

[0095] In one or more embodiments, the particle dispersant comprises: triethanolamine, triethoxyvinylsilane, vinyltrimethoxysilane, 5-hexenyltrimethoxysilane, or a combination thereof.

[0096] In one or more embodiments, the atomizing further comprises supplying a suspension of the particles, the liquid medium, the binder, and the particle dispersant.

[0097] In one or more embodiments, for a given set of operating conditions, the volume-based average particle size (D 50 ) of the aggregates is less than the comparative volume-based average particle size (D 50 ) of comparative aggregates formed by a method using the given set of operating conditions but using ethanol as the liquid medium.

[0098] In another aspect, a method of applying a surface treatment to a packed honeycomb body comprises: atomizing a dispersion of inorganic material particles into liquid-particle-dispersant droplets, the liquid-particle-dispersant droplets comprising: a liquid medium comprising water and one or more solvents having a boiling point lower than water, a particle dispersant, and particles; evaporating at least substantially all of the liquid medium from the droplets to form aggregates of the particles; and depositing the aggregates within the packed honeycomb body; wherein the deposited aggregates are disposed on the porous walls, or within the porous walls, or both on and within the porous walls, the honeycomb body comprising a honeycomb structure having a plurality of axially porous walls that define a plurality of axial channels in the axial direction.

[0099] In one or more embodiments, atomization further comprises a binder and a dispersion such that the droplets are liquid - particle - dispersant - binder droplets, and the agglomerates further comprise a binder. In one or more embodiments, atomization further comprises supplying a suspension of particles, a liquid medium, and a particle dispersant. In one or more embodiments, one or more solvents comprise ethanol, methanol, acetone, hexane, or a combination thereof. In one or more embodiments, the particle dispersant comprises acetic acid, triethanolamine, triethoxyvinylsilane, vinyltrimethoxysilane, and / or 5 - hexenyltrimethoxysilane.

[0100] In one or more embodiments, for a given set of operating conditions, the volume - based average particle size (D 50 ) of the agglomerates is less than the comparative volume - based average particle size (D 50 ) of comparative agglomerates formed by a method using the given set of operating conditions but using only water as the liquid medium.

[0101] One aspect is a filter article prepared by any of the methods herein, the filter article comprising a filtration efficiency of greater than or equal to 95.0% and a loading of deposited agglomerates of less than or equal to 6 grams of deposited agglomerates per liter of the honeycomb filter body. In one or more embodiments, the filtration efficiency is greater than or equal to 99.0%. In one or more embodiments, the loading of deposited agglomerates is greater than or equal to 2 grams of deposited agglomerates per liter of the honeycomb filter body. In one or more embodiments, the loading of deposited agglomerates is less than or equal to 3 grams of deposited agglomerates per liter of the honeycomb filter body.

[0102] Device

[0103] Examples of equipment for a process for depositing an inorganic material with a binder on a ceramic honeycomb are shown in Figures 2 - 6 . Generally, equipment suitable for the methods herein includes a duct that defines a chamber. The duct may have several sections that define different spaces and chambers. In one or more embodiments, droplets and a gaseous carrier are transported through the duct, and the outlet end of the duct is close to the packed honeycomb. The duct may comprise a converging section for engaging the proximal end of the honeycomb. The advantage of the converging section is to enhance fluid convection. During the deposition step, the duct may remain in sealed fluid communication with the packed honeycomb. In one or more embodiments, the duct is adiabatic, or substantially adiabatic. In some embodiments, the nozzle temperature is adjusted to achieve good atomization.

[0104] In some embodiments, a chamber with a circular cross-section is beneficial for keeping the agglomerates entrained in the gaseous carrier stream. In various embodiments, a pipe with a circular cross-section reduces and / or prevents recirculation zones or "dead zones" that may be caused, for example, by the presence of corners.

[0105] In one or more embodiments, the average temperature of the pipe wall is lower than the temperature of the gaseous carrier stream. In one or more embodiments, the average temperature of the pipe wall is higher than the temperature of the gaseous carrier stream.

[0106] Hereinafter, Figures 2 - 3 Figs. 5 - 6 schematically show co-current flow, wherein the paths of the droplets and the gaseous carrier stream are substantially parallel after entering the evaporation section. Figure 4 It shows that the carrier gas contacts the atomizing nozzle by means of a first path, and wherein the path of the droplets and the second path of the carrier gas are substantially perpendicular to each other before entering the evaporation section of the pipe.

[0107] Figure 2 Fig. 5 shows an apparatus 500 for depositing a filter material including an inorganic material according to an embodiment herein. The apparatus 500 includes a pipe 551, a deposition zone 531, an outlet zone 536, an outlet conduit 540, and a flow driver 545.

[0108] The pipe 551 extends from a first end 550 to a second end 555, defining a chamber of the pipe, the chamber including: a static pressure space 503 at the first end 550 and an evaporation chamber 523 downstream of the static pressure space 503. In one or more embodiments, the pipe 551 is substantially adiabatic. That is, the pipe 551 may have no external heat source. The evaporation chamber 523 is defined by an evaporation section 553 of the pipe 551. In the present embodiment, the evaporation section includes a first part 527 with a non-uniform diameter and a second part 529 with a substantially uniform diameter. The evaporation section 553 includes an inlet end 521 and an outlet end 525. The diameter of the first part 527 with a non-uniform diameter increases from the inlet end 521 towards the part 529 with a uniform diameter, thereby forming a diversion space for the fluid to occupy.

[0109] A carrier gas is supplied through conduit 501 to duct 551, which may have a heat source to produce heated carrier gas 505. Atomizing gas 515 and suspension 510 are respectively supplied through separate delivery conduits (such as tubes or pipelines) to nozzle 520, which is located at the inlet end 521 of evaporation section 553 and is in fluid communication with duct 551, specifically in this embodiment in fluid communication with evaporation chamber 523. Suspension 510 is atomized in nozzle 520 with atomizing gas 515. In one or more embodiments, suspension 510 comprises an inorganic material, a liquid medium, and a particulate dispersant, and supplies a liquid-particle-dispersant stream to the nozzle. The liquid-particle-dispersant stream is atomized into liquid-particle-dispersant droplets by atomizing gas 515 through nozzle 520. In one or more other embodiments, suspension 510 comprises an inorganic material, a liquid medium, a particulate dispersant, and a binder, and supplies a liquid-particle-dispersant-binder stream to the nozzle. The liquid-particle-dispersant-binder stream is atomized into liquid-particle-dispersant-binder droplets by atomizing gas 515 through nozzle 520.

[0110] In one or more embodiments, heated carrier gas 505 flows through nozzle 520. The atomizing gas 515 can be heated to form a heated atomizing gas. The temperature of the nozzle can be adjusted as needed.

[0111] The outlet flow of nozzle 520 and the flow of heated carrier gas 505 are both along Figure 2 the indicated "Z" direction. There may be a diffusion zone 522 downstream of the nozzle, where at least some mixing occurs. In this embodiment, diffusion zone 522 is located in evaporation chamber 523, but in other embodiments, diffusion zone 522 can be located in static pressure space 503, depending on the position of the nozzle.

[0112] The outlet flow of the nozzle is mixed with heated carrier gas 505 to form a gas-liquid-particle mixture or a gas-liquid-particle-binder mixture, which flows through the chamber of duct 551. Specifically, the gas-liquid-particle or gas-liquid-particle-binder mixture flows through evaporation chamber 523 of evaporation section 553 and enters deposition zone 531 at the outlet end 525 of evaporation section 553. During mixing, the gas-liquid-particle or gas-liquid-particle-binder mixture is heated by the heated carrier gas in the chamber.

[0113] In this embodiment, the outlet flow of the nozzle and the heated carrier gas enter evaporation chamber 523 of evaporation section 553 from substantially the same direction. In evaporation chamber 523, substantially all of the liquid medium and dispersant in the droplets are evaporated, thereby forming particles or agglomerates of particles and binder, which are dispersed in the gaseous carrier stream composed of the carrier gas and the atomizing gas.

[0114] The deposition zone 531 that is in fluid communication with the conduit 551 houses the packed ceramic honeycomb body 530, such as a wall-flow particulate filter. The inner diameter of the deposition zone 531 is larger than the outer diameter of the ceramic honeycomb body 530. To prevent leakage of the gas carrying the ceramic powder, the ceramic honeycomb body 530 is sealed to the inner diameter of the deposition zone 531, and a suitable seal is, for example, an inflatable "inner tube". A pressure gauge marked "PG" measures the pressure difference upstream and downstream of the particulate filter.

[0115] A gas-liquid-particulate mixture or a gas-liquid-particulate-binder mixture flows into the ceramic honeycomb body 530, thereby depositing the inorganic material of the suspension on the ceramic honeycomb body. Specifically, the agglomerates and the gaseous carrier stream enter the honeycomb body, such that the gaseous carrier stream passes through the porous walls of the honeycomb body, and the walls of the honeycomb body capture the agglomerates, wherein the agglomerates and / or their aggregates are deposited on or within the walls of the honeycomb body. When the ceramic honeycomb body is post-treated, the inorganic material adheres to the ceramic honeycomb body. In one embodiment, the binder material causes the agglomerates to adhere or stick to the walls of the honeycomb body.

[0116] Downstream of the ceramic honeycomb body 530 is an outlet zone 536 that defines an outlet chamber 535. A flow driver 545 is located downstream of the ceramic honeycomb body 530 and is in fluid communication with the deposition zone 531 and the outlet zone 536 via an outlet conduit 540. Non-limiting examples of the flow driver are: a fan, a blower, and a vacuum pump. The aerosolized suspension is dried and deposited on one or more walls of the particulate filter in the form of agglomerates of the filter material, which exist in the form of discrete regions of the filter material, or in some parts or some embodiments, in the form of a layer, or both, wherein the agglomerates are composed of primary particles of the inorganic material.

[0117] The flow direction through embodiments such as the apparatus 500 is considered to be downward, for example, substantially parallel to the direction of gravity. In other embodiments, the apparatus is configured such that the flow is directed in a substantially upward or vertical direction.

[0118] In Figure 3 is shown an apparatus 600 for depositing a filter material including an inorganic material according to embodiments herein, the apparatus comprising a conduit 651, a deposition zone 631, an outlet zone 636, an outlet conduit 640, and a flow driver 645.

[0119] The conduit 651 extends from a first end 650 to a second end 655, defining a chamber of the conduit, the chamber including: a static pressure space 603 at the first end 650 and an evaporation chamber 623 downstream of the static pressure space 603. In one or more embodiments, the diameter of the conduit 651 defining the static pressure space 603 may be equal to the diameter of the evaporation portion 653 of the conduit 651 defining the evaporation chamber 623. In one or more embodiments, the conduit 651 is substantially adiabatic. That is, the conduit 651 may have no external heat source. In the present embodiment, the evaporation chamber 623 includes a single portion 629 having a substantially uniform diameter. The evaporation portion 653 includes an inlet end 621 and an outlet end 625.

[0120] A carrier gas is supplied to the conduit 651 through a conduit 601, which may have a heat source to generate a heated carrier gas 605. The atomizing gas 615 and the suspension 610 are supplied to a nozzle 620 through separate delivery conduits (such as tubes or pipes), respectively, the nozzle being located at the inlet end 621 of the evaporation portion 653 and in fluid communication with the conduit 651, specifically in fluid communication with the evaporation chamber 623 in the present embodiment. The suspension 610 is atomized with the atomizing gas 615 in the nozzle 620. In one or more embodiments, the suspension 610 includes an inorganic material, a liquid medium, and a particulate dispersant, and supplies a liquid-particle-dispersant stream to the nozzle. The liquid-particle-dispersant stream is atomized into liquid-particle-dispersant droplets with the atomizing gas 615 through the nozzle 620. In one or more other embodiments, the suspension 610 includes an inorganic material, a liquid medium, a particulate dispersant, and an adhesive, and supplies a liquid-particle-dispersant-adhesive stream to the nozzle. The liquid-particle-dispersant-adhesive stream is atomized into liquid-particle-dispersant-adhesive droplets with the atomizing gas 615 through the nozzle 620. In one or more embodiments, the heated carrier gas 605 flows through the nozzle 620. The atomizing gas 615 may be heated to form a heated atomizing gas. The temperature of the nozzle can be adjusted as needed.

[0121] The outlet flow of the nozzle 620 and the flow of the heated carrier gas 605 are both along Figure 3 the indicated "Z" direction. In a specific embodiment, a diffusion zone 622 is located downstream of the nozzle, where at least some mixing occurs. In the present embodiment, the diffusion zone 622 is located in the evaporation chamber 623, but in other embodiments, the diffusion zone may be located in the static pressure space 603, depending on the position of the nozzle.

[0122] The outlet flow of the nozzle mixes with the heated carrier gas 605 to form a gas-liquid-particle mixture or a gas-liquid-particle-binder mixture, which flows through the chamber of the conduit 651. Specifically, the gas-liquid-particle mixture or the gas-liquid-particle-binder mixture flows through the evaporation chamber 623 of the evaporation section 653 and enters the deposition zone 631 at the outlet end 625 of the evaporation section 653. During mixing, the gas-liquid-particle mixture or the gas-liquid-particle-binder mixture is heated by the heated carrier gas within the chamber.

[0123] In this embodiment, the outlet flow of the nozzle and the carrier gas enter the evaporation chamber 623 of the evaporation section 653 from substantially the same direction. In the evaporation chamber 623, substantially all of the liquid medium in the droplets is evaporated to form particles or agglomerates of particles and binder, and the agglomerates are dispersed in the gaseous carrier stream, which consists of the carrier gas and the atomizing gas.

[0124] The deposition zone 631 in fluid communication with the conduit 651 houses a packed ceramic honeycomb 630, such as a wall-flow particulate filter. The inner diameter of the deposition zone 631 is larger than the outer diameter of the ceramic honeycomb 630. To prevent leakage of the gas carrying the ceramic powder, the ceramic honeycomb 630 is sealed to the inner diameter of the deposition zone 631, and a suitable seal is, for example, an inflatable "inner tube". A pressure gauge marked "PG" measures the pressure difference upstream and downstream of the particulate filter. The gas-liquid-particle-binder mixture flows into the ceramic honeycomb 630, thereby depositing the inorganic material of the suspension on the ceramic honeycomb. Specifically, the agglomerates and the gaseous carrier stream enter the honeycomb, such that the gaseous carrier stream passes through the porous walls of the honeycomb, and the walls of the honeycomb capture the agglomerates, where the agglomerates are deposited on or within the walls of the honeycomb. During post-treatment of the ceramic honeycomb, the inorganic material adheres to the ceramic honeycomb. In one embodiment, the binder material causes the agglomerates to adhere or stick to the walls of the honeycomb.

[0125] Downstream of the ceramic honeycomb 630 is an outlet zone 636, which defines an outlet chamber 635. A flow driver 645 is located downstream of the ceramic honeycomb 630 and is in fluid communication with the deposition zone 631 and the outlet zone 636 through an outlet conduit 640. Non-limiting examples of the flow driver are: fans, blowers, and vacuum pumps. The aerosolized suspension is dried and deposited on one or more walls of the particulate filter in the form of agglomerates of the filter material, which exist as discrete regions of the filter material, or in some parts or some embodiments, in the form of a layer, or both, where the agglomerates are composed of primary particles of the inorganic material.

[0126] The flow direction through an embodiment such as device 600 is considered to be downward, e.g., substantially parallel to the direction of gravity. In other embodiments, the device is configured such that the flow is directed in a substantially upward or vertical direction.

[0127] In Figure 4 , a device 900 for depositing a filter material including an inorganic material according to an embodiment herein is shown, the device including a duct 951, a deposition zone 931, an exit zone 936, an exit conduit 940, and a flow driver 945.

[0128] The duct 951 extends from a first end 950 to a second end 955 and includes a right cylindrical portion 928, all of which define a chamber of the duct that includes: a first static pressure space 903 at the first end 950, an evaporation chamber 923 downstream of the static pressure space 903, and a second static pressure space 929 defined by the right cylindrical portion 928. In one or more embodiments, the diameter of the duct 951 defining the static pressure space 903 may be equal to the diameter of the first inlet location 921 of the evaporation portion 953 of the duct 951. In one or more embodiments, the duct 951 is substantially adiabatic. That is, the duct 951 may be without an external heat source. The evaporation chamber 923 is defined by the evaporation portion 953 of the duct 951. The evaporation portion 953 includes a first inlet location 921 from the first static pressure space 903, a second inlet location 924 from the second static pressure space 929, and an exit end 925. In some embodiments, some evaporation may occur in at least a portion of the second static pressure space 929 defined by the right cylindrical portion 928.

[0129] The carrier gas is supplied through conduit 901 in a first path to duct 951. The conduit may have a first heat source 906a to produce a primarily heated carrier gas 905a entering the first static pressure space 903 and optionally another secondarily heated carrier gas 905b entering the second static pressure space 929 through a second path. The atomizing gas 915 and the suspension 910 are supplied to nozzle 920 through separate delivery conduits (such as tubes or pipes), which is located in the second static pressure space 929 of the right cylindrical portion 928 and is in fluid communication with the evaporation chamber 923 of the evaporation section 953. The suspension 910 is atomized in nozzle 920 with the atomizing gas 915. The suspension may be contained in a suspension container, and the liquid pressure may be applied and controlled by a gas supply, which in some embodiments is in the form of a cylinder. In one or more embodiments, the pressure is controlled by a digital automatic pressure regulator or a piezoelectric actuator valve. According to one or more embodiments, the atomizing gas comprises nitrogen or air. In one or more embodiments, the suspension 910 comprises an inorganic material, a liquid medium, and a particulate dispersant, and a liquid-particle-dispersant stream is supplied to the nozzle. The liquid-particle-dispersant stream is atomized into liquid-particle-dispersant droplets in nozzle 920 with the atomizing gas 915. In one or more other embodiments, the suspension 910 comprises an inorganic material, a liquid medium, a particulate dispersant, and a binder, and a liquid-particle-dispersant-binder stream is supplied to the nozzle. The liquid-particle-dispersant-binder stream is atomized into liquid-particle-dispersant-binder droplets in nozzle 920 with the atomizing gas 915.

[0130] In one or more embodiments, the secondarily heated carrier gas 905b flows through nozzle 920, and the temperature of the nozzle can be adjusted as needed. A second heat source 906b is located downstream of nozzle 920 for heating the suspension 910 atomized in nozzle 920.

[0131] The outlet flow of nozzle 920 and the flow of the secondarily heated carrier gas 905b (when present) are both along Figure 4 the indicated "X" direction. The flow of the primarily heated carrier gas 905a is along Figure 4 the indicated "Z" direction. There may be a diffusion zone 922 downstream of the nozzle, where at least some mixing occurs. In the present embodiment, the diffusion zone 922 is at least partially located in the second static pressure space 929, but in other embodiments, the diffusion zone 922 may be located in the evaporation chamber 923, depending on the position of the nozzle.

[0132] The outlet flow of the nozzle mixes with the heating carrier gases 905a and 905b, thereby forming a gas-liquid-particle mixture or a gas-liquid-particle-binder mixture that flows through the chamber of the conduit 951. Specifically, the gas-liquid-particle mixture or the gas-liquid-particle-binder mixture flows through the evaporation chamber 923 of the evaporation section 953 and enters the deposition zone 931 at the outlet end 925 of the evaporation section 953. During mixing, the gas-liquid-particle mixture or the gas-liquid-particle-binder mixture is heated by the heating carrier gas within the chamber. A third heat source 906c is located within the evaporation chamber 923, and the outlet flow of the nozzle and the primary carrier gas 905a enter the evaporation chamber 923 of the evaporation section 953.

[0133] In the present embodiment, the outlet flow of the nozzle and the primary carrier gas 905a enter the evaporation chamber 923 of the evaporation section 953 from a substantially vertical direction. In the evaporation chamber 923, substantially all of the liquid medium in the droplets is evaporated, thereby forming particles or agglomerates of particles and binder, and the agglomerates are dispersed in the gaseous carrier stream, which is composed of the carrier gas and the atomizing gas.

[0134] The deposition zone 931 in fluid communication with the conduit 951 houses a packed ceramic honeycomb 930, such as a wall-flow particulate filter. The inner diameter of the deposition zone 931 is greater than the outer diameter of the ceramic honeycomb 930. To prevent leakage of the gas carrying the ceramic powder, the ceramic honeycomb 930 is sealed to the inner diameter of the deposition zone 931, and a suitable seal is, for example, an inflatable "inner tube". A pressure gauge marked "PG" measures the pressure difference upstream and downstream of the particulate filter. The gas-liquid-particle-binder mixture flows into the ceramic honeycomb 930, thereby depositing the inorganic material of the suspension on the ceramic honeycomb. Specifically, the agglomerates and the gaseous carrier stream enter the honeycomb, such that the gaseous carrier stream passes through the porous walls of the honeycomb, and the walls of the honeycomb capture the agglomerates, where the agglomerates are deposited on or within the walls of the honeycomb. During post-treatment of the ceramic honeycomb, the inorganic material adheres to the ceramic honeycomb. In one embodiment, the binder causes the agglomerates to adhere or stick to the walls of the honeycomb.

[0135] Downstream of the ceramic honeycomb 930 is an outlet zone 936, which defines an outlet chamber 935. A flow driver 945 is located downstream of the ceramic honeycomb 930 and is in fluid communication with the deposition zone 931 and the outlet zone 936 through an outlet conduit 940. Non-limiting examples of the flow driver are: a fan, a blower, and a vacuum pump. The aerosolized suspension is dried and deposited on one or more walls of the particulate filter in the form of agglomerates of the filter material, which exist in discrete regions of the filter material, or in some parts or some embodiments, in the form of a layer, or both, where the agglomerates are composed of primary particles of the inorganic material.

[0136] The overall flow direction through embodiments such as device 900 is considered to be downward, for example, substantially parallel to the direction of gravity. In other embodiments, the device is configured such that the flow is directed in a substantially upward or vertical direction.

[0137] Figure 5 Device 700 for depositing a filter material including an inorganic material according to embodiments herein is shown. Device 700 includes a conduit 751, a deposition zone 731, an exit zone 736, an exit conduit 740, and a flow driver 745.

[0138] Conduit 751 extends from a first end 750 to a second end 755, defining a chamber of the conduit that includes a static pressure space 703 at the first end 750 and an evaporation chamber 723 downstream of the static pressure space 703. In one or more embodiments, the diameter of conduit 751 defining static pressure space 703 may be equal to the diameter of the evaporation portion 753 of the inlet end 721. In one or more embodiments, conduit 751 is substantially adiabatic. That is, conduit 751 may be without an external heat source. Evaporation chamber 723 is defined by the evaporation portion 753 of conduit 751, which in the present embodiment includes a first portion 727 of non-uniform diameter and a second portion 729 of substantially uniform diameter. Evaporation portion 753 includes an inlet end 721 and an outlet end 725. The diameter of the first portion 727 of non-uniform diameter decreases from the outlet end 725 towards the portion 729 of uniform diameter, creating a diversion space for the fluid as it enters deposition zone 731.

[0139] A carrier gas is supplied to conduit 751 through conduit 701, which may have a heat source to produce a heated carrier gas 705. An atomizing gas 715 and a suspension 710 are supplied to nozzle 720 through separate delivery conduits (such as tubes or lines), respectively. The nozzle is located at the inlet end 721 of evaporation portion 753 and is in fluid communication with conduit 751, specifically in fluid communication with evaporation chamber 723 in the present embodiment. Suspension 710 is atomized in nozzle 720 with atomizing gas 715. In one or more embodiments, suspension 710 includes an inorganic material, a liquid medium, and a particulate dispersant, and supplies a liquid - particulate - dispersant stream to the nozzle. The liquid - particulate - dispersant stream is atomized into liquid - particulate - dispersant droplets with atomizing gas 715 through nozzle 720. In one or more other embodiments, suspension 710 includes an inorganic material, a liquid medium, a particulate dispersant, and an adhesive, and supplies a liquid - particulate stream to the nozzle. The liquid - particulate - adhesive stream is atomized into liquid - particulate - adhesive droplets with atomizing gas 715 through nozzle 720.

[0140] In one or more embodiments, a heated carrier gas 705 flows through a nozzle 720. The atomizing gas 715 can be heated to form a heated atomizing gas. The temperature of the nozzle can be adjusted as needed.

[0141] The flow at the outlet of the nozzle 720 and the flow of the heated carrier gas 705 are both along Figure 5 the indicated "Z" direction. There may be a diffusion zone 722 downstream of the nozzle where at least some mixing occurs. In this embodiment, the diffusion zone 722 is located in the evaporation chamber 723, but in other embodiments, the diffusion zone can be located in the static pressure space 703, depending on the position of the nozzle.

[0142] The outlet flow of the nozzle is mixed with the heated carrier gas 705 to form a gas - liquid - particle mixture or a gas - liquid - particle - binder mixture, which flows through the chamber of the conduit 751. Specifically, the gas - liquid - particle mixture or the gas - liquid - particle - binder mixture flows through the evaporation chamber 723 of the evaporation section 753 and enters the deposition zone 731 at the outlet end 725 of the evaporation section 753. During mixing, the gas - liquid - particle mixture or the gas - liquid - particle - binder mixture is heated by the heated carrier gas within the chamber.

[0143] In this embodiment, the outlet flow of the nozzle and the heated carrier gas enter the evaporation chamber 723 of the evaporation section 753 from substantially the same direction. In the evaporation chamber 723, substantially all of the liquid medium in the droplets is evaporated, thereby forming particles or agglomerates of particles and binder, and the agglomerates are dispersed in the gaseous carrier stream, which is composed of the carrier gas and the atomizing gas.

[0144] The deposition zone 731 in fluid communication with the conduit 751 houses a packed ceramic honeycomb 730, such as a wall - flow particulate filter. The inner diameter of the deposition zone 731 is larger than the outer diameter of the ceramic honeycomb 730. To prevent leakage of the gas carrying ceramic powder, the ceramic honeycomb 730 is sealed to the inner diameter of the deposition zone 731, and a suitable seal is, for example, an inflatable "inner tube". A pressure gauge marked "PG" measures the pressure difference upstream and downstream of the particulate filter. The gas - liquid - particle - binder mixture flows into the ceramic honeycomb 730, thereby depositing the inorganic material of the suspension on the ceramic honeycomb. Specifically, the agglomerates and the gaseous carrier stream enter the honeycomb, such that the gaseous carrier stream passes through the porous walls of the honeycomb, and the walls of the honeycomb capture the agglomerates, where the agglomerates and / or their aggregates are deposited on or within the walls of the honeycomb. When the ceramic honeycomb is post - processed, the inorganic material adheres to the ceramic honeycomb. In one embodiment, the binder causes the agglomerates to adhere or stick to the walls of the honeycomb.

[0145] Downstream of the ceramic honeycomb body 730 is an exit zone 736, which defines an exit chamber 735. A flow driver 745 is located downstream of the ceramic honeycomb body 730 and is in fluid communication with the deposition zone 731 and the exit zone 736 through an exit conduit 740. Non-limiting examples of flow drivers are: fans, blowers, and vacuum pumps. The droplets of the atomized suspension are aerosolized and dried and deposited on one or more walls of the particulate filter in the form of agglomerates of the filter material, which exist in the form of discrete regions of the filter material, or in some parts or some embodiments, in the form of a layer, or both, where the agglomerates are composed of primary particles of an inorganic material.

[0146] The flow direction through embodiments such as device 700 is considered to be downward, for example, substantially parallel to the direction of gravity. In other embodiments, the device is configured such that the flow is directed in a substantially upward or vertical direction.

[0147] Figure 6 Device 800 for depositing a filter material including an inorganic material according to embodiments herein is shown, the device 800 including a duct 851, a deposition zone 831, an exit zone 836, an exit conduit 840, and a flow driver 845.

[0148] The duct 851 extends from a first end 850 to a second end 855, defining a chamber of the duct, the chamber including: a static pressure space 803 at the first end 850 and an evaporation chamber 823 downstream of the static pressure space 803. In one or more embodiments, the duct 851 is substantially adiabatic. That is, the duct 851 may have no external heat source. The evaporation chamber 823 is defined by an evaporation portion 853 of the duct 851, which in this embodiment includes a first portion 827 of non-uniform diameter and a second portion 829 of substantially uniform diameter. The evaporation portion 853 includes an inlet end 821 and an outlet end 825. The diameter of the first portion 827 of non-uniform diameter decreases from the outlet end 825 towards the portion 829 of uniform diameter, creating a diverging space for the fluid as it enters the deposition zone 831. In some embodiments, the evaporation portion 853 is configured to have a single portion of substantially uniform diameter, similar to Figure 3 . Alternatively, the evaporation portion 853 has a portion of non-uniform diameter that increases from the inlet end 821 towards the portion of uniform diameter, similar to Figure 2 .

[0149] The carrier gas is supplied through conduit 801 to duct 851, and the conduit may have a heat source to generate heated carrier gas 805. The atomizing gas 815 and the suspension 810 are respectively supplied through separate delivery conduits (such as tubes or pipes) to a plurality of nozzles 820a, 820b, and 820c, which are in fluid communication with the static pressure space 803. Each nozzle has an atomizing gas flowing in, such as 815a supplying nozzle 820a, and 815b supplying nozzle 820b. Each nozzle has a suspension flowing in, such as 810a supplying nozzle 820a, and 810b supplying nozzle 820b. Optionally, each nozzle has a heated carrier gas supplied, such as 802a supplying nozzle 820a, and 802b supplying nozzle 820b. Although Figure 6 the illustrated embodiment shows three nozzles, in other embodiments, any number of nozzles may be used. The suspension 810 is atomized in the nozzle 820 with the atomizing gas 815. In one or more embodiments, the suspension 810 comprises an inorganic material, a liquid medium, and a particulate dispersant, and supplies a liquid-particle-dispersant stream to the nozzle. The liquid-particle-dispersant stream is atomized into liquid-particle-dispersant droplets by the atomizing gas 815 through the nozzle 820. In one or more other embodiments, the suspension 810 comprises an inorganic material, a liquid medium, a particulate dispersant, and a binder, and supplies a liquid-particle-dispersant-binder stream to the nozzle. The liquid-particle-dispersant-binder stream is atomized into liquid-particle-dispersant-binder droplets by the atomizing gas 815 through the nozzle 820.

[0150] In one or more embodiments, the heated carrier gas 805 and optionally 802a and 802b flow through the nozzle. The atomizing gases 815a and 815b can be heated to form heated atomizing gases. The temperature of the nozzles can be adjusted individually or collectively as needed.

[0151] The flow of the heated carrier gas 805 is along Figure 6 the "Z" direction shown. Although the outlet flow of the nozzles 820a, 820b, and 820c may be angled towards the center of the duct 851, after mixing with the heated carrier gas 805, the outlet flow of the nozzles generally follows the "Z" direction. There may be a mixing zone 822 downstream of the nozzles, where at least some mixing occurs. In the present embodiment, the mixing zone 822 is located in the static pressure space 803, but in other embodiments, the mixing zone may be located in the evaporation chamber 823, depending on the position of the nozzles.

[0152] The outlet flow of the nozzle mixes with the heated carrier gas 805, thereby forming a gas - liquid - particle mixture or a gas - liquid - particle - binder mixture that flows through the chamber of conduit 851. Specifically, the gas - liquid - particle mixture or the gas - liquid - particle - binder mixture flows through the evaporation chamber 823 of the evaporation section 853 and enters the deposition zone 831 at the outlet end 825 of the evaporation section 853. During mixing, the gas - liquid - particle mixture or the gas - liquid - particle - binder mixture is heated by the heated carrier gas within the chamber.

[0153] In the present embodiment, the outlet flow of the nozzle and the heated carrier gas enter the evaporation chamber 823 of the evaporation section 853 from substantially the same direction. In the evaporation chamber 823, substantially all of the liquid medium in the droplets is evaporated, thereby forming particles or agglomerates of particles and binder, and the agglomerates are dispersed in the gaseous carrier stream, which is composed of the carrier gas and the atomizing gas.

[0154] The deposition zone 831 in fluid communication with the conduit 851 houses a packed ceramic honeycomb 830, such as a wall - flow particulate filter or a "wall - flow filter". The inner diameter of the deposition zone 831 is larger than the outer diameter of the ceramic honeycomb 830. To prevent leakage of the gas carrying the ceramic powder, the ceramic honeycomb 830 is sealed to the inner diameter of the deposition zone 831, and a suitable seal is, for example, an inflatable "inner tube". A pressure gauge marked "PG" measures the pressure difference upstream and downstream of the particulate filter. The gas - liquid - particle - binder mixture flows into the ceramic honeycomb 830, thereby depositing the inorganic material of the suspension on the ceramic honeycomb. Specifically, the agglomerates and the gaseous carrier stream enter the honeycomb, such that the gaseous carrier stream passes through the porous walls of the honeycomb, and the walls of the honeycomb capture the agglomerates, where the agglomerates and / or their aggregates are deposited on or within the walls of the honeycomb. During post - treatment of the ceramic honeycomb, the inorganic material adheres to the ceramic honeycomb. In one embodiment, the binder causes the agglomerates to adhere or stick to the walls of the honeycomb.

[0155] Downstream of the ceramic honeycomb 830 is an outlet zone 836, which defines an outlet chamber 835. A flow driver 845 is located downstream of the ceramic honeycomb 830 and is in fluid communication with the deposition zone 831 and the outlet zone 836 through an outlet conduit 840. Non - limiting examples of flow drivers are: fans, blowers, and vacuum pumps. The droplets of the atomized suspension are aerosolized and dried and deposited in the form of agglomerates of filter material on one or more walls of the particulate filter, and these agglomerates exist in the form of discrete regions of filter material, or in some parts or some embodiments, in the form of a layer, or both, where the agglomerates are composed of primary particles of inorganic material.

[0156] The flow direction through an embodiment such as device 800 is considered to be downward, e.g., substantially parallel to the direction of gravity. In other embodiments, the device may be configured such that the flow is directed in a substantially upward or vertical direction.

[0157] Honeycomb body overview

[0158] The ceramic article of the present disclosure includes a honeycomb body, which is composed of a porous ceramic honeycomb structure having porous walls, and the porous walls have wall surfaces defining a plurality of internal channels.

[0159] In some embodiments, the porous ceramic walls include materials such as filter materials, and in some portions or some embodiments, the filter materials may include a porous inorganic layer disposed on one or more surfaces of the walls. In some embodiments, the filter materials include one or more inorganic materials, such as one or more ceramics or refractory materials. In some embodiments, the filter materials are disposed on the walls to provide enhanced filtration efficiency, including local filtration efficiency through and at the walls and global filtration efficiency through the honeycomb body, at least when the honeycomb body is first used as a filter after the honeycomb body is in a clean state or a regenerated state, e.g., before a large amount of ash and / or soot accumulates inside the honeycomb body after the honeycomb body has been used as a filter for a long time.

[0160] In one aspect, the filter materials are present in the form of layers in some portions or some embodiments, and the layers are disposed on the surfaces of one or more walls of the honeycomb structure. In some embodiments, the layers are porous to allow gas to flow through the walls. In some embodiments, the layers are present in the form of a continuous coating on at least a portion or the entire surface of one or more walls. In some embodiments in this aspect, the filter materials are flame-deposited filter materials.

[0161] In another aspect, the filter materials are present in the form of a plurality of discrete regions of filter materials, and the discrete regions are disposed on the surfaces of one or more walls of the honeycomb structure. The filter materials may partially block a portion of some of the pores of the porous walls while still allowing gas to flow through the walls. In some embodiments in this aspect, the filter materials are aerosol-deposited filter materials. In some preferred embodiments, the filter materials include a plurality of inorganic particle aggregates, and the aggregates are composed of inorganic materials or ceramics or refractory materials. In some embodiments, the aggregates are porous to allow gas to flow through the aggregates.

[0162] In some embodiments, the honeycomb body comprises a porous ceramic honeycomb body having a first end, a second end, and a plurality of walls with wall surfaces defining a plurality of internal channels. A deposition material, such as a filter material, is disposed on one or more wall surfaces of the honeycomb body, and in some portions or some embodiments, the deposition material may be a porous inorganic layer.It can be a deposition material for a porous inorganic layer. For example, a filter material has a porosity measured by mercury intrusion porosimetry, SEM, or X-ray tomography within the following ranges: about 20% to about 95%, or about 25% to about 95%, or about 30% to about 95%, or about 40% to about 95%, or about 45% to about 95%, or about 50% to about 95%, or about 55% to about 95%, or about 60% to about 95%, or about 65% to about 95%, or about 70% to about 95%, or about 75% to about 95%, or about 80% to about 95%, or about 85% to about 95%, about 30% to about 95%, or about 40% to about 95%, or about 45% to about 95%, or about 50% to about 95%, or about 55% to about 95%, or about 60% to about 95%, or about 65% to about 95%, or about 70% to about 95%, or about 75% to about 95%, or about 80% to about 95%, or about 85% to about 95%, or about 20% to about 90%, or about 25% to about 90%, or about 30% to about 90%, or about 40% to about 90%, or about 45% to about 90%, or about 50% to about 90%, or about 55% to about 90%, or about 60% to about 90%, or about 65% to about 90%, or about 70% to about 90%, or about 75% to about 90%, or about 80% to about 90%, or about 85% to about 90%, or about 20% to about 85%, or about 25% to about 85%, or about 30% to about 85%, or about 40% to about 85%, or about 45% to about 85%, or about 50% to about 85%, or about 55% to about 85%, or about 60% to about 85%, or about 65% to about 85%, or about 70% to about 85%, or about 75% to about 85%, or about 80% to about 85%, or about 20% to about 80%, or about 25% to about 80%, or about 30% to about 80%, or about 40% to about 80%, or about 45% to about 80%, or about 50% to about 80%, or about 55% to about 80%, or about 60% to about 80%, or about 65% to about 80%, or about 70% to about 80%, or about 75% to about 80%. And it can be a deposition material for a porous inorganic layer. For example, a filter material has an average thickness greater than or equal to 0.5 μm and less than or equal to 50 μm, or greater than or equal to 0.5 μm and less than or equal to 45 μm, greater than or equal to 0.5 μm and less than or equal to 40 μm, or greater than or equal to 0.5 μm and less than or equal to 35 μm, or greater than or equal to 0.5 μm and less than or equal to 30 μm, greater than or equal to 0.5 μm and less than or equal to 25 μm, or greater than or equal to 0.5 μm and less than or equal to 20 μm, or greater than or equal to 0.5 μm and less than or equal to 15 μm, greater than or equal to 0.5 μm and less than or equal to 10 μm. Various embodiments of the honeycomb body and methods for forming such a honeycomb body will be specifically described with reference to the accompanying drawings.

[0163] In some embodiments, the material comprises a filter material, and in some embodiments, an inorganic filter material. According to one or more embodiments, the inorganic filter material provided herein comprises discrete regions and / or discontinuous layers formed from an inlet end to an outlet end, the discrete regions and / or discontinuous layers comprising discrete and discontinuous blocks of material or filter material and binder, which are composed of primary particles in substantially spherical secondary particles or aggregates. In one or more embodiments, the primary particles are non-spherical. In one or more embodiments, "substantially spherical" refers to aggregates having a cross-sectional roundness in the range of about 0.8 to about 1 or about 0.9 to about 1, where 1 represents a perfect circle. In one or more embodiments, 75% of the primary particles deposited on the honeycomb body have a roundness less than 0.8. In one or more embodiments, the secondary particles or aggregates deposited on the honeycomb body have an average roundness greater than 0.9, greater than 0.95, greater than 0.96, greater than 0.97, greater than 0.98 or greater than 0.99.

[0164] Roundness can be measured using a scanning electron microscope (SEM). The term "cross-sectional roundness (or simply roundness)" is a value represented by the equation shown below. A circle with a roundness of 1 is a perfect circle.

[0165] Roundness = (4π × cross-sectional area) / (cross-sectional perimeter) 2 。

[0166] The honeycomb body in one or more embodiments may comprise a honeycomb structure and a deposited material, such as a filter material disposed on one or more walls of the honeycomb structure. In some embodiments, the deposited material, such as a filter material, is applied to the surface of the walls present within the honeycomb structure, where the walls have a surface defining a plurality of internal channels.

[0167] When present, the internal channels can have a variety of cross-sectional shapes, such as circular, elliptical, triangular, square, pentagonal, hexagonal, or checkerboard combinations or any of these, and can be arranged in any suitable geometric configuration. When present, the internal channels can be discrete or cross-connected and can extend from a first end of the honeycomb body through the honeycomb body to a second end opposite the first end.

[0168] Now referring to Figure 7, depicts a honeycomb body 100 according to one or more embodiments shown and described herein. In an embodiment, the honeycomb body 100 may include a plurality of walls 115 defining a plurality of internal channels 110. The plurality of internal channels 110 and the intersecting channel walls 115 extend between a first end 105 (which may be an inlet end) and a second end 135 (which may be an outlet end) of the honeycomb body. The honeycomb body may have one or more channels plugged at one or both of the first end 105 and the second end 135. The pattern of the plugged channels of the honeycomb body is not limited. In some embodiments, the pattern of plugged and unplugged channels at one end of the honeycomb body may be, for example, a checkerboard pattern, where alternating channels at one end of the honeycomb body are plugged. In some embodiments, the channels plugged at one end of the honeycomb body have corresponding unplugged channels at the other end, and the channels unplugged at one end of the honeycomb body have corresponding plugged channels at the other end.

[0169] In one or more embodiments, the honeycomb body may be formed of cordierite, aluminum titanate, enstatite, mullite, forsterite, corundum (SiC), spinel, sapphirine, and periclase. Generally, cordierite has the formula Mg2Al4Si5O 18 composition. In some embodiments, the pore size, porosity, and pore size distribution of the ceramic material are controlled, for example, by changing the particle size of the ceramic raw materials. Additionally, pore formers may be included in the ceramic batch used to form the honeycomb body.

[0170] In some embodiments, the walls of the honeycomb body may have an average thickness greater than or equal to 25 μm to less than or equal to 250 μm, such as greater than or equal to 45 μm to less than or equal to 230 μm, greater than or equal to 65 μm to less than or equal to 210 μm, greater than or equal to 65 μm to less than or equal to 190 μm, or greater than or equal to 85 μm to less than or equal to 170 μm. The walls of the honeycomb body may be described as having a base portion composed of a body portion (also referred to herein as the body) and a surface portion (also referred to herein as the surface). The surface portion of the wall extends from the surface of the wall of the honeycomb body into the wall towards the body portion of the honeycomb body. The surface portion may extend from 0 (zero) to a depth of about 10 μm into the base portion of the wall of the honeycomb body. In some embodiments, the surface portion may extend into the base portion of the wall by about 5 μm, about 7 μm, or about 9 μm (i.e., a depth of 0 (zero)). The body portion of the wall of the honeycomb body is composed of the thickness of the wall minus the surface portion. Thus, the body portion of the wall of the honeycomb body can be determined by the following equation:

[0171] t 总 - 2t 表面

[0172] where t 总 is the total thickness of the wall, and t 表面 is the thickness of the wall surface.

[0173] In one or more embodiments, the body of the honeycomb (before applying any filter material) has a body median pore size that is greater than or equal to 7 μm to less than or equal to 25 μm, such as greater than or equal to 12 μm to less than or equal to 22 μm, or greater than or equal to 12 μm to less than or equal to 18 μm. For example, in some embodiments, the body of the honeycomb may have a body median pore size of about 10 μm, about 11 μm, about 12 μm, about 13 μm, about 14 μm, about 15 μm, about 16 μm, about 17 μm, about 18 μm, about 19 μm, or about 20 μm. Generally, the pore sizes of any given material exist in a statistical distribution. Thus, the term "median pore size" or "d50" (before applying any filter material) refers to a length measurement such that, based on the statistical distribution of all the pores, the pore sizes of 50% of the pores are above the length measurement and the pore sizes of the remaining 50% of the pores are below the length measurement. The pores in the ceramic body can be created by at least one of the following: (1) the particle size and size distribution of the inorganic batch material; (2) the furnace / heat treatment firing time and temperature profile; (3) the furnace atmosphere (e.g., low or high oxygen and / or water content), and; (4) pore formers such as polymers and polymer particles, starches, wood flour, hollow inorganic particles, and / or graphite / carbon particles.

[0174] In a specific embodiment, the median pore diameter (d50) of the honeycomb body (before applying any filter material) ranges from 10 μm to about 16 μm, for example 13 - 14 μm, and d10 refers to a length measurement value such that, based on the statistical distribution of all pores, the pore diameters of 90% of the pores are above the length measurement value, and the pore diameters of the remaining 10% of the pores are below the length measurement value, and the length measurement value is about 7 μm. In a specific embodiment, d90 refers to a length measurement value such that, based on the statistical distribution of all pores, the pore diameters of 10% of the pores of the honeycomb body (before applying any filter material) are above the length measurement value, and the pore diameters of the remaining 90% of the pores are below the length measurement value, and the length measurement value is about 30 μm. In a specific embodiment, the average or mean diameter (D50) of the secondary particles or aggregates is greater than 0.5 μm and less than 5 μm, d90 is greater than 1 μm and less than 5 μm, and d10 is greater than 0.3 μm and less than 2 μm, for example about 2 μm. In a specific embodiment, it has been determined that when the average aggregate size D50 and the average wall pore diameter d50 of the body honeycomb are such that the ratio of the average aggregate size D50 to the average wall pore diameter d50 of the honeycomb body is in the range of 5:1 to 16:1, excellent filtration efficiency results and low pressure drop results are achieved. In a more specific embodiment, the ratio of the average aggregate size D50 to the average wall pore diameter d50 of the honeycomb body (before applying any filter material) is in the range of 6:1 to 16:1, 7:1 to 16:1, 8:1 to 16:1, 9:1 to 16:1, 10:1 to 16:1, 11:1 to 16:1, or 12:1 to 6:1, providing excellent filtration efficiency results and low pressure drop results.

[0175] In some embodiments, as measured by mercury intrusion porosimetry, the honeycomb body may have a body porosity (excluding coatings) of greater than or equal to 50% to less than or equal to 75%. Other methods for measuring porosity include scanning electron microscopy (SEM) and X-ray tomography, both of which are particularly valuable for independently measuring surface porosity and volume porosity. In one or more embodiments, the body porosity of the honeycomb body may be, for example, in the range of about 50% to about 75%, in the range of about 50% to about 70%, in the range of about 50% to about 65%, in the range of about 50% to about 60%, in the range of about 50% to about 58%, in the range of about 50% to about 56%, or in the range of about 50% to about 54%.

[0176] In one or more embodiments, the surface portion of the honeycomb body has a surface median pore size greater than or equal to 7 μm and less than or equal to 20 μm, such as greater than or equal to 8 μm and less than or equal to 15 μm, or greater than or equal to 10 μm and less than or equal to 14 μm. For example, in some embodiments, the surface of the honeycomb body may have a surface median pore size of about 8 μm, about 9 μm, about 10 μm, about 11 μm, about 12 μm, about 13 μm, about 14 μm, or about 15 μm.

[0177] In some embodiments, before applying the filter material deposit, the surface of the honeycomb body may have a surface porosity of greater than or equal to 35% and less than or equal to 75% as measured by mercury intrusion porosimetry, SEM, or X-ray tomography. In one or more embodiments, the surface porosity of the honeycomb body may be, for example, less than 65%, such as less than 60%, less than 55%, less than 50%, less than 48%, less than 46%, less than 44%, less than 42%, less than 40%, less than 48%, or less than 36%.

[0178] Now referring to Figure 8 and 9 , a honeycomb body in the form of a particulate filter 200 is schematically depicted. The particulate filter 200 can be used as a wall-flow filter to filter particulate matter from an exhaust gas stream 250, such as an exhaust gas stream discharged from a gasoline engine. In this case, the particulate filter 200 is a gasoline particulate filter. The particulate filter 200 generally includes a honeycomb body having a plurality of channels 201 or cells that extend between an inlet end 202 and an outlet end 204, defining a total length La ( Figure 9 as shown). The channels 201 of the particulate filter 200 are formed by and at least partially defined by a plurality of intersecting channel walls 206 that extend from the inlet end 202 to the outlet end 204. The particulate filter 200 may also include a skin layer 205 surrounding the plurality of channels 201. The skin layer 205 may be extruded during the formation of the channel walls 206 or formed as a post-applied skin layer during subsequent processing, such as by applying a skin adhesive to the outer peripheral portion of the channels.

[0179] Figure 9 The axial cross-section of the particulate filter 200 shown in Figure 8 is presented. In some embodiments, certain channels are designated as inlet channels 208, and certain other channels are designated as outlet channels 210. In some embodiments of the particulate filter 200, at least a first group of channels may be plugged with plugs 212. Generally, the plugs 212 are disposed near the ends (i.e., the inlet end or the outlet end) of the channels 201. The plugs are typically arranged in a predetermined pattern, such as in the Figure 8 checkerboard pattern shown, where every other channel is plugged at one end. AsFigure 9 As depicted, the inlet channels 208 can be plugged at or near the outlet end 204, and the outlet channels 210 can be plugged at or near the inlet end 202 on channels that do not correspond to the inlet channels. Thus, each cell can be plugged only at or near one end of the particulate filter.

[0180] While Figure 8 a checkerboard plugging pattern is generally depicted, it should be understood that alternative plugging patterns can be used in the porous ceramic honeycomb article. In the embodiments described herein, the particulate filter 200 can be formed with a channel density of up to about 600 channels per square inch (cpsi). For example, in some embodiments, the particulate filter 100 can have a channel density in the range of about 100 cpsi to about 600 cpsi. In some other embodiments, the particulate filter 100 can have a channel density in the range of about 100 cpsi to about 400 cpsi or even about 200 cpsi to about 300 cpsi.

[0181] In the embodiments described herein, the channel walls 206 of the particulate filter 200 can have a thickness greater than about 4 mils (101.6 μm). For example, in some embodiments, the thickness of the channel walls 206 can be in the range of about 4 mils up to about 30 mils (762 μm). In some other embodiments, the thickness of the channel walls 206 can be in the range of about 7 mils (177.8 μm) to about 20 mils (508 μm).

[0182] In some embodiments of the particulate filter 200 described herein, prior to applying any coating to the particulate filter 200, the channel walls 206 of the particulate filter 200 can have a bare open porosity of P% ≧ 35% (i.e., the porosity before applying any coating to the honeycomb). In some embodiments, the bare open porosity of the channel walls 206 can be such that 40% ≦ P% ≦ 75%. In other embodiments, the bare open porosity of the channel walls 206 can be such that 45% ≦ P% ≦ 75%, 50% ≦ P% ≦ 75%, 55% ≦ P% ≦ 75%, 60% ≦ P% ≦ 75%, 45% ≦ P% ≦ 70%, 50% ≦ P% ≦ 70%, 55% ≦ P% ≦ 70% or 60% ≦ P% ≦ 70%.

[0183] In addition, in some embodiments, the channel walls 206 of the particulate filter 200 are formed such that, prior to the application of any coating (i.e., as bare), the pore distribution in the channel walls 206 has a median pore diameter of ≦30 μm. For example, in some embodiments, the median pore diameter can be ≧8 μm and less than or ≦30 μm. In other embodiments, the median pore diameter can be ≧10 μm and less than or ≦30 μm. In other embodiments, the median pore diameter can be ≧10 μm and less than or ≦25 μm. In some embodiments, particulate filters produced with a median pore diameter greater than about 30 μm have reduced filtration efficiency, while particulate filters produced with a median pore diameter less than about 8 μm may be difficult to penetrate with a washcoat containing a catalyst. Thus, in some embodiments, it is desirable to maintain the median pore diameter of the channel walls in the range of about 8 μm to about 30 μm, such as in the range of 10 μm to about 20 μm.

[0184] In one or more embodiments described herein, the honeycomb body of the particulate filter 200 is formed from a metal or ceramic material, such as cordierite, silicon carbide, alumina, aluminum titanate, or any other ceramic material suitable for high temperature particulate filtration applications. By way of example, the particulate filter 200 can be formed from cordierite by mixing a batch of ceramic precursor materials, which can include compositional materials suitable for producing a ceramic article that predominantly contains a cordierite crystalline phase. Generally, compositional materials suitable for forming cordierite include a combination of inorganic components that include talc, a source of silicon dioxide formation, and a source of alumina formation. The batch composition can additionally contain a clay, such as kaolin. The cordierite precursor batch composition can also contain an organic component, such as an organic pore former, which is added to the batch mixture to achieve a desired pore size distribution. By way of example, the batch composition can contain starch suitable for use as a pore former and / or other processing aids. Alternatively, the compositional materials can include one or more cordierite powders suitable for forming a sintered cordierite honeycomb structure upon firing and an organic pore forming material.

[0185] The batch composition may additionally include one or more processing aids such as binders and liquid media such as water or a suitable solvent. The processing aids are added to the batch mixture to plasticize the batch mixture and generally improve processing, reduce drying time, reduce cracking during firing, and / or help produce the desired properties in the honeycomb body. For example, the binder may include an organic binder. Suitable organic binders include water-soluble cellulose ether binders such as methylcellulose, hydroxypropyl methylcellulose, methylcellulose derivatives, hydroxyethyl acrylate, polyvinyl alcohol, and / or any combination thereof. Incorporating the organic binder into the plasticized batch composition allows the plasticized batch composition to be easily extruded. In some embodiments, the batch composition may include one or more optional shaping or processing aids such as lubricants that aid in the extrusion of the plasticized batch mixture. Exemplary lubricants may include tall oil, sodium stearate, or other suitable lubricants.

[0186] After mixing the ceramic precursor material batch with the appropriate processing aids, the ceramic precursor material batch is extruded and dried to form a green honeycomb body that includes an inlet end and an outlet end and a plurality of channel walls extending between the inlet end and the outlet end. Thereafter, the green honeycomb body is fired according to a firing schedule suitable for producing a fired honeycomb body. The fired honeycomb body is then packed with a ceramic packing composition in a predetermined packing pattern in at least a first set of channels, and the fired honeycomb body is fired again to ceramify the packing and fix the packing in the channels.

[0187] In various embodiments, the honeycomb body is configured to filter particulate matter from an air stream such as an exhaust stream from a gasoline engine. Accordingly, in view of these filtration requirements of the honeycomb body, the median pore size, porosity, geometry, and other design aspects of the body and surface of the honeycomb body are selected. As an example, and as Figure 10 illustrated in the embodiment of, which depicts a simplified schematic view of the wall 310 of the honeycomb body 300, which may be as Figure 8 and 9in the form of the particulate filter shown and having pores (not shown). The filter material deposit 320 is disposed on the wall 310, and / or in the wall, and / or on and in the wall. In some embodiments, the filter material deposit is sintered by heat treatment or otherwise bonded to the wall. The filter material deposit 320 comprises particles 325 deposited on and / or in the wall 310 of the honeycomb body 300 and helps to prevent particulate matter, such as soot and / or ash, from leaving the honeycomb body with the gas stream 330 and helps to prevent particulate matter from clogging the base portion of the wall 310 of the honeycomb body 300. In this way, and according to embodiments, the filter material deposit 320 can be used as the primary filter component, while the base portion of the honeycomb body can be configured to minimize the pressure drop in other ways, for example, compared to a honeycomb body without such a filter material deposit. The filter material deposit is delivered by the aerosol deposition method disclosed herein.

[0188] As mentioned above, the material on the honeycomb body wall is very thin compared to the thickness of the base portion of the honeycomb body wall, which can be an inorganic layer in some parts or some embodiments. As will be discussed in further detail below, the material that can be an inorganic layer on the honeycomb body can be formed by a method that allows the deposited material to be applied in a very thin application or in layers in some parts to the surface of the wall of the honeycomb body. In an embodiment, the average thickness of the material that can be a deposition area or an inorganic layer on the base portion of the honeycomb body wall is greater than or equal to 0.5 μm and less than or equal to 50 μm, or greater than or equal to 0.5 μm and less than or equal to 45 μm, greater than or equal to 0.5 μm and less than or equal to 40 μm, or greater than or equal to 0.5 μm and less than or equal to 35 μm, or greater than or equal to 0.5 μm and less than or equal to 30 μm, greater than or equal to 0.5 μm and less than or equal to 25 μm, or greater than or equal to 0.5 μm and less than or equal to 20 μm, or greater than or equal to 0.5 μm and less than or equal to 15 μm, greater than or equal to 0.5 μm and less than or equal to 10 μm.

[0189] As discussed above, the deposition material, which can be an inorganic layer in some sections or some embodiments, can be applied to the honeycomb body wall by a method that allows the deposition material (which can be an inorganic layer) to have a small median pore size. This small median pore size allows the material (which can be an inorganic layer) to filter a high percentage of the particulates and prevent the particulates from penetrating the honeycomb body and settling into the honeycomb pores. According to an embodiment, the small median pore size of the material (which can be an inorganic layer) improves the filtration efficiency of the honeycomb body. In one or more embodiments, the material, which can be an inorganic layer, on the honeycomb body wall has a median pore size greater than or equal to 0.1 μm and less than or equal to 5 μm, such as greater than or equal to 0.5 μm and less than or equal to 4 μm, or greater than or equal to 0.6 μm and less than or equal to 3 μm. For example, in some embodiments, the material, which can be an inorganic layer, on the honeycomb body wall can have a median pore size of about 0.5 μm, about 0.6 μm, about 0.7 μm, about 0.8 μm, about 0.9 μm, about 1 μm, about 2 μm, about 3 μm, or about 4 μm.

[0190] Although in some embodiments, the deposition material, which can be an inorganic layer, on the honeycomb body wall can cover substantially 100% of the wall surface defining the internal channels of the honeycomb body, in other embodiments, the material, which can be an inorganic layer, on the honeycomb body wall covers less than substantially 100% of the wall surface defining the internal channels of the honeycomb body. For example, in one or more embodiments, the deposition material, which can be an inorganic layer, on the honeycomb body wall covers at least 70% of the wall surface defining the internal channels of the honeycomb body, at least 75% of the wall surface defining the internal channels of the honeycomb body, at least 80% of the wall surface defining the internal channels of the honeycomb body, at least 85% of the wall surface defining the internal channels of the honeycomb body, at least 90% of the wall surface defining the internal channels of the honeycomb body, or at least 85% of the wall surface defining the internal channels of the honeycomb body.

[0191] As referred to above Figure 7 and 8 As described, the honeycomb body can have a first end and a second end. The first end and the second end are spaced apart by an axial length. In some embodiments, the filter material deposit on the honeycomb body wall can extend the entire axial length of the honeycomb body (i.e., extend 100% along the axial length). However, in other embodiments, the material, which can be an inorganic layer, on the honeycomb body wall extends along at least 60% of the axial length, such as at least 65% along the axial length, at least 70% along the axial length, at least 75% along the axial length, at least 80% along the axial length, at least 85% along the axial length, at least 90% along the axial length, or at least 95% along the axial length.

[0192] In an embodiment, the material on the honeycomb body wall extends from the first end of the honeycomb body to the second end of the honeycomb body, which may be an inorganic layer in some parts or some embodiments. In some embodiments, the material on the honeycomb body wall that may be an inorganic layer extends the entire distance from the first surface of the honeycomb body to the second surface of the honeycomb body (i.e., extends 100% along the distance from the first surface of the honeycomb body to the second surface of the honeycomb body). However, in one or more embodiments, the layer or material on the honeycomb body wall that may be an inorganic layer extends 60% along the distance between the first surface and the second surface of the honeycomb body, such as 65% along the distance between the first surface and the second surface of the honeycomb body, 70% along the distance between the first surface and the second surface of the honeycomb body, 75% along the distance between the first surface and the second surface of the honeycomb body, 80% along the distance between the first surface and the second surface of the honeycomb body, 85% along the distance between the first surface and the second surface of the honeycomb body, 90% along the distance between the first surface and the second surface of the honeycomb body, or 95% along the distance between the first surface and the second surface of the honeycomb body.

[0193] According to an embodiment, a honeycomb body having a low pressure drop and a low thickness and porosity of the filter material on the honeycomb body is selected, allowing the honeycomb body of the embodiment to have a lower initial pressure drop compared to other honeycomb bodies. In an embodiment, the loading amount of the layer on the honeycomb body is in the range of 0.3 g / L to 30 g / L. For example, the loading amount on the honeycomb body is in the range of 1 g / L to 30 g / L, or the loading amount on the honeycomb body is in the range of 3 g / L to 30 g / L. In other embodiments, the loading amount of the layer on the honeycomb body is in the range of 1 g / L to 20 g / L. For example, the loading amount on the honeycomb body is in the range of 1 g / L to 10 g / L. In a specific embodiment, the loading amount of the layer on the honeycomb body is in the range of 1 to 9 g / L, 1 to 8 g / L, 1 to 7 g / L, 1 to 8 g / L, 1 to 5 g / L, 1 to 4 g / L, 1 to 3 g / L, 2 to 10 g / L, 2 to 9 g / L, 2 to 8 g / L, 2 to 7 g / L, 2 to 6 g / L, 2 to 5 g / L, 2 to 4 g / L, 3 to 10 g / L, 3 to 9 g / L, 3 to 8 g / L, 3 to 7 g / L, 3 to 6 g / L, 3 to 5 g / L, 4 to 10 g / L, 4 to 9 g / L, 4 to 8 g / L, 4 to 7 g / L, or 4 to 6 g / L. In some embodiments, due to the application of the porous layer, the increase in the pressure drop on the honeycomb body is less than 20% of that of the uncoated honeycomb body. In other embodiments, the increase can be less than or equal to 9%, or less than or equal to 8%. In other embodiments, the increase in the pressure drop on the honeycomb body is less than or equal to 7%, for example, less than or equal to 6%. In other embodiments, the increase in the pressure drop on the honeycomb body is less than or equal to 5%, for example, less than or equal to 4%, or less than or equal to 3%.

[0194] Without being bound by any particular theory, it is believed that even before ash or soot accumulation occurs in the honeycomb body, the small pore diameters in the filter material deposits on the honeycomb body walls allow the honeycomb body to have good filtration efficiency. The filtration efficiency of the honeycomb body is measured using the protocol outlined in Tandon et al., 65 Chemical Engineering Science 4751-60 (2010). As used herein, the initial filtration efficiency of the honeycomb body refers to a new or regenerated honeycomb body that does not contain any measurable soot or ash loading. In an embodiment, the initial filtration efficiency (i.e., clean filtration efficiency) of the honeycomb body is greater than or equal to 70%, for example, greater than or equal to 80%, or greater than or equal to 85%. In other embodiments, the initial filtration efficiency of the honeycomb body is greater than 90%, for example, greater than or equal to 93%, or greater than or equal to 95%, or greater than or equal to 98%.

[0195] According to an embodiment, the material on the honeycomb body wall, which is an inorganic filter material in some embodiments, is thin and has porosity, and also has good chemical durability and physical stability in some embodiments. In an embodiment, the chemical durability and physical stability of the filter material deposit on the honeycomb body can be determined by subjecting the honeycomb body to a test cycle including a burnout cycle and an aging test, and measuring the initial filtration efficiency before and after the test cycle. For example, an exemplary method for measuring the chemical durability and physical stability of a honeycomb body includes: measuring the initial filtration efficiency of the honeycomb body; loading soot onto the honeycomb body under simulated operating conditions; burning out the accumulated soot at about 650 °C; performing an aging test on the honeycomb body at 1050 °C and 10% humidity for 12 hours; and measuring the filtration efficiency of the honeycomb body. Multiple soot accumulation and burnout cycles can be performed. A small change in filtration efficiency (ΔFE) from before the test cycle to after the test cycle indicates better chemical durability and physical stability of the filter material deposit on the honeycomb body. In some embodiments, ΔFE is less than or equal to 5%, such as less than or equal to 4%, or less than or equal to 3%. In other embodiments, ΔFE is less than or equal to 2%, or less than or equal to 1%.

[0196] In some embodiments, the filter material deposit on the honeycomb body wall can include one or a mixture of ceramic components, for example, ceramic components selected from the group consisting of: SiO2, Al2O3, MgO, ZrO2, CaO, TiO2, CeO2, Na2O, Pt, Pd, Ag, Cu, Fe, Ni, and mixtures thereof. Thus, the filter material deposit on the honeycomb body wall can include oxide ceramics. As discussed in more detail below, the method for forming a filter material deposit on a honeycomb body according to an embodiment can allow customization of the filter material composition for a given application. This can be beneficial because the ceramic components can be combined to match, for example, the physical properties of the honeycomb body, such as the coefficient of thermal expansion (CTE) and Young's modulus, etc., which can improve the physical stability of the honeycomb body. In some embodiments, the filter material deposit on the honeycomb body wall can include cordierite, aluminum titanate, enstatite, mullite, forsterite, corundum (SiC), spinel, sapphirine, and periclase.

[0197] In some embodiments, the composition of the filter material deposit on the honeycomb body wall is the same as the composition of the honeycomb body. However, in other embodiments, the composition of the filter material is different from the composition of the wall of the honeycomb body substrate.

[0198] The properties of the filter material deposit and the properties of the honeycomb body as a whole can be attributed to the ability to apply a sparse or thin porous filter material that has a small median pore size relative to the main honeycomb body.

[0199] In some embodiments, a method of forming a honeycomb body includes forming or obtaining a mixture or suspension comprising a ceramic precursor material and a solvent. The ceramic precursor material of the filter material precursor includes ceramic materials used as sources of, for example, SiO2, Al2O3, TiO2, MgO, ZrO2, CaO, CeO2, Na2O, Pt, Pd, Ag, Cu, Fe, Ni, etc.

[0200] In one or more embodiments, the suspension is atomized with an atomizing gas to form liquid-particle-binder droplets composed of a liquid medium, a binder material, and particles, which are directed to the honeycomb body, and then the agglomerates formed upon removal or evaporation of the liquid medium are deposited on the honeycomb body. In some embodiments, during deposition of the aerosol onto the honeycomb body, one or more channels of the honeycomb body may be plugged at one end, e.g., the first end of the honeycomb body. In some embodiments, the plugged channels may be removed after depositing the aerosol. However, in other embodiments, the channels may remain plugged even after aerosol deposition. The pattern of the plugged channels of the honeycomb body is not limited, and in some embodiments, all channels of the honeycomb body may be plugged at one end. In other embodiments, only a portion of the channels of the honeycomb body may be plugged at one end. In such embodiments, the pattern of the plugged and non-plugged channels at one end of the honeycomb body is not limited and may be, for example, a checkerboard pattern where alternating channels at one end of the honeycomb body are plugged. By plugging all or a portion of the channels at one end of the honeycomb body during aerosol deposition, the aerosol can be evenly distributed within the channels of the honeycomb body.

[0201] According to one or more embodiments, a binder having high temperature resistance (e.g., greater than 400 °C) is included in the agglomerates and the filter material deposit to enhance the integrity of the agglomerates and the deposit even at the high temperatures encountered in an exhaust gas treatment system. In a specific embodiment, the filter material may comprise from about 5 to 25 wt% alkoxy-siloxane resin. The microstructure of the filter material deposit is similar to the deposition morphology after various tests described below. Inorganic binders may also be used in one or more embodiments. After a high flow blow test (high flow test at 850 Nm 3 / h), the filtration efficiency of both samples is higher than 60%. The tests show that the binders, including organic and inorganic binders, bind the primary particles together to form secondary particles (also referred to as agglomerates), and the secondary particles adhere to the filter walls even when exposed to the high temperatures encountered in the engine exhaust stream. According to one or more embodiments, other inorganic and organic binders may also be utilized, such as silicates, phosphates (e.g., AlPO4, AlH2(PO4)3), sols (e.g., mSiO2·nH2O, Al(OH) x ·(H2O) 6-x) and alkoxides to increase mechanical strength, for example, by suitable curing processes.

[0202] Packed honeycomb body containing inorganic material

[0203] Embodiments of the present disclosure relate to a packed honeycomb body that includes a porous wall and an inorganic material deposited on, in, or both on and in the porous wall, which provides a filtering article configured to filter particulates from an exhaust gas stream. In a specific embodiment, the filtering article includes a gasoline particulate filter (GPF) for removing particulates from gasoline engine exhaust. The exhaust gas to be filtered enters an intake unit and passes through the unit wall and exits the filter through an outlet channel. When the gas passes through the filter and then exits, particulates are trapped on or inside the unit wall. According to one or more embodiments, the porous wall of the filtering article (which has an inorganic material deposited on, in, or both on and in the porous wall) provides improved filtration efficiency and excellent durability, including durability when exposed to water.

[0204] In one or more embodiments, the inorganic material includes fine particles or primary particles of an inorganic material (such as alumina), particle-binder agglomerates (referred to as "agglomerates") composed of particles and a binder, and aggregates of the particle-binder agglomerates. In one or more embodiments, a "fine particle" or "primary particle" refers to the smallest discrete mass of an inorganic material. In one or more embodiments, an "agglomerate" refers to a mass of primary particles or fine particles and a binder, where the primary particles or fine particles are bound together by the binder. In one or more embodiments, an "aggregate of particle-binder agglomerates" or "aggregate of primary particle-binder agglomerates" (referred to as "aggregate") refers to a mass formed by aggregating individual particle-binder agglomerates or primary particle-binder agglomerates, which are bound together by the binder. In one or more embodiments, some aggregates and separate, for example, non-aggregated agglomerates are deposited on the porous wall of the honeycomb filter body. In one or more embodiments, at least a portion of the primary particles or fine particles exist in the form of discrete masses that are not part of an agglomerate or aggregate within, on, or both within and on the porous wall. In one or more embodiments, at least a portion of the particle-binder agglomerates or primary particle-binder agglomerates exist in the form of discrete masses that are not part of an aggregate within, on, or both within and on the porous wall.

[0205] In one or more embodiments, the inorganic material within and / or on the porous walls of a filter article in the form of a stuffed honeycomb body is present in the form of "clusters" or "chains" of agglomerates and / or aggregates. In some embodiments, the clusters or chains provide an inorganic material morphology that is finger-like, fibrous, or sponge-like, such as one or more of the morphologies in a form similar to a sea wool sponge.

[0206] As discussed herein, according to embodiments, the inorganic material is formed from a suspension comprising nanoparticles (e.g., inorganic particles, ceramic particles, refractory particles, alumina particles, etc.), a binder (e.g., a silicon-containing binder and / or an aqueous binder), and a liquid medium (e.g., an alcohol or water). The suspension is delivered to a nozzle that ejects droplets of the suspension with the assistance of an air stream. The liquid medium evaporates from the droplets to form spherical agglomerates of the nanoparticles. The binder serves as one or more of an agglomeration promoter, an aggregation promoter, a chain promoter, and a cluster promoter. Some of the spherical agglomerates are transported to the porous ceramic wall and remain on the surface of the porous ceramic wall (on, in, or above the surface pores present in the wall), or in the pores within the porous ceramic wall (below the surface of the porous ceramic wall), or contact other previously deposited agglomerates disposed in or on the porous ceramic wall, thereby forming aggregates of the spherical agglomerates therein or thereon. Other spherical agglomerates contact other spherical agglomerates during transport towards the honeycomb filter body, thereby forming aggregates of the spherical agglomerates, where the aggregates are then transported towards the porous ceramic wall and then the aggregates remain on the surface of the porous ceramic wall (on, in, or above the surface pores present in the wall), or in the pores within the porous ceramic wall (below the surface of the porous ceramic wall), or contact other previously deposited agglomerates or aggregates disposed in or on the porous ceramic wall, thereby forming aggregates of the spherical agglomerates therein or thereon.

[0207] Thus, according to one or more embodiments, the inorganic deposit is composed of individual aggregates of nanoparticles (e.g., spherical aggregates of nanoparticles), aggregates of the aggregates, and / or porous clusters or chains of aggregates of spherical aggregates, wherein some of the clusters or chains are disposed within pores in or below the surface of the porous ceramic wall, and / or wherein some of the clusters are disposed on the surface of the porous ceramic wall. In some embodiments, some of the porous clusters are porous cluster islands, comprising aggregates of exposed aggregates (e.g., spherical aggregates). In some embodiments, the porous cluster or cluster island comprises one or more chains of two or more aggregates, each chain extending from the porous ceramic wall in a substantially outward direction. In some embodiments, the plurality of outwardly extending chains together provide a morphology similar to that of a member of the group consisting of: fingers, tufts, sponges (e.g., sea wool sponges), and fans. In some embodiments, at least one chain includes a free end of the chain extending out of the surface of the porous ceramic wall. In some embodiments, the inorganic material on the honeycomb body is present in the form of an inorganic deposit comprising a network of aggregated spherical aggregates of inorganic material particles.

[0208] In an embodiment, the loading of the inorganic material present on the honeycomb body is in the range of 0.3 g / L to 30 g / L on the honeycomb body, such as in the range of 1 g / L to 30 g / L on the honeycomb body, or in the range of 3 g / L to 30 g / L on the honeycomb body. In other embodiments, the loading of the inorganic material on the honeycomb body is in the range of 1 g / L to 20 g / L, such as the loading on the honeycomb body is in the range of 1 g / L to 10 g / L. In a specific embodiment, the loading of the inorganic material on the honeycomb body is in the range of 1 to 9 g / L, 1 to 8 g / L, 1 to 7 g / L, 1 to 8 g / L, 1 to 5 g / L, 1 to 4 g / L, 1 to 3 g / L, 2 to 10 g / L, 2 to 9 g / L, 2 to 8 g / L, 2 to 7 g / L, 2 to 6 g / L, 2 to 5 g / L, 2 to 4 g / L, 3 to 10 g / L, 3 to 9 g / L, 3 to 8 g / L, 3 to 7 g / L, 3 to 6 g / L, 3 to 5 g / L, 4 to 10 g / L, 4 to 9 g / L, 4 to 8 g / L, 4 to 7 g / L, or 4 to 6 g / L. The loading of the inorganic material is the weight of the added material in grams divided by the geometric component volume in liters. The geometric component volume is based on the external dimensions of the honeycomb filter body (or the stuffed honeycomb body).

[0209] In one or more embodiments, the inorganic material particles have a BET surface area in the range of 5 m 2 / g to 15 m 2 / g, 5 m 2 / g to 14 m 2 / g, 5 m 2 / g to 13 m 2 / g, 5 m 2 / g to 12 m2 / g, 5 m 2 / g to 12 m 2 / g or 5 m 2 / g to 10 m 2 The surface area within the range of / g.

[0210] In one or more embodiments, the inorganic material deposit on the honeycomb body does not contain rare earth oxides, such as cerium oxide, lanthanum oxide, and yttrium oxide. In one or more embodiments, the inorganic material does not contain a catalyst, such as an oxidation catalyst, such as platinum group metals (e.g., platinum, palladium, and rhodium) or a selective catalytic reduction catalyst, such as a copper, nickel, or iron-promoted molecular sieve (e.g., zeolite).

[0211] In one or more embodiments, before heat-treating the honeycomb body containing an inorganic material on or in the porous wall or on and in the porous wall, the honeycomb body further contains a water-soluble binder, such as a water-soluble silicon-containing binder, a water-soluble silicate binder, or a water-soluble aluminate binder. In one or more embodiments, based on the weight of the organic material on the honeycomb body, the binder is present in a range of 5 wt% to 40 wt%, 5 wt% to 35 wt%, 5 wt% to 30 wt%, 5 wt% to 25 wt%, 5 wt% to 20 wt%, 5 wt% to 15 wt%, or 5 wt% to 10 wt%. In one or more embodiments, the binder contains silicon. In one or more embodiments, the silicon-containing binder is a silicone resin, or a siloxane, or an alkoxysiloxane, or a silicate. In one or more embodiments, the silicon-containing binder is composed of an inorganic component and an organic component. In one or more embodiments, the silicon-containing binder transforms into silica when heated. In one or more embodiments, the silicon-containing binder is composed of an inorganic component and an organic component, and wherein when heated, the organic component is expelled and the inorganic component transforms into silica.

[0212] Examples

[0213] The embodiments will be further understood through the following non-limiting examples.

[0214] Wall-flow filter. The diameter and length of the wall-flow filter substrate used in the examples are 4.252 inches (10.8 cm) and 4.724 inches (12 cm), respectively. The CPSI and wall thickness are 200 mils and 8 mils, respectively. The median pore size of the body is about 13 μm.

[0215] Raw materials. Unless otherwise specified in the examples, the following raw materials are used. The deposited inorganic material is alumina. The atomizing gas is air, and the carrier gas is air. The liquid medium and the particle dispersant are changed.

[0216] The alumina sold under the trade name AKP-53 is provided by Sumitomo. The alumina particles have an average size of primary alumina particles of 0.17 μm and a BET surface area of 13.7 m 2 / g.

[0217] The liquid medium is selected from one or more materials in Table 1.

[0218] Table 1. Properties of the liquid medium

[0219]

[0220]

[0221] Reference 1: https: / / www.engineeringtoolbox.com / surface-tension-d_962.html

[0222] Reference 2: https: / / www.engineeringtoolbox.com / absolute-viscosity-liquids-d_1259.html Reference 3: PubChem (National Library of Medicine, USA)

[0223] The particle dispersant has been determined in the examples.

[0224] All suspensions contain: 11 wt% alumina, 87% liquid medium, and 2% particle dispersant. In these examples, no binder is used.

[0225] Coating machine. All examples are carried out according to Figure 11Preparation of a co-flow aerosol deposition system. The apparatus 1000 includes a duct 1051, an injection pump 1009, an exit zone 1036, an exit conduit 1040, and a blower 1045. A substrate 1030 is located at one end of the duct 1051. The duct 1051 defines an evaporation chamber 1023. The injection pump 1009 supplies a suspension 1010 to a nozzle 1020. An atomizing gas, namely air, is supplied by a conduit 1115. A carrier gas, namely air, is supplied by a conduit 1001. Thermocouples T1, T2, and T3 are located in the apparatus. Pressure gauges PG1 and PG2 are located upstream and downstream of the substrate 1030. An SU2A-SS nozzle from Spraying Systems Co. is used as the nozzle 1020 in the system. For spraying, the suspension 1010 is supplied to the nozzle 1020 by a syringe driven by the injection pump 1009. For the experiment, the atomizing air 1115 of the nozzle 1020 is set to 78 psi. The total flow rate through the chamber is controlled by the blower 1045. For the experiment, the blower 1045 operates at 25 Hz. A belt heater and an in-line gas heater are used as the heater 1006 of the chamber. Throughout the experiment, the temperature downstream of the coating chamber is maintained at 60 °C.

[0226] The flow conditions are listed in Table 2.

[0227] Table 2. Flow conditions

[0228] Suspension flow rate (ml / min) 5 Atomizing gas Air pressure about 70 psi Total carrier Blower frequency 25 Hz

[0229] The volume-based particle size is measured by analyzing SEM images. The diameter value is obtained by measuring the size of the aggregates from the SEM images. The reported value is the volume-weighted average.

[0230] According to one or more embodiments, a honeycomb filter body comprising a filter material deposit, the filter material deposit being an inorganic deposit, is characterized according to one or more of the following tests, the inorganic deposit being disposed within the honeycomb filter body to produce a filter article.

[0231] Filtration efficiency (FE) by filtration performance

[0232] A filtration test using filtration performance is used to evaluate the filtration efficiency performance of the deposited inorganic material disposed within the honeycomb filter body.

[0233] The filtration efficiency (in percentage %) is calculated as follows: where C is the detected particle concentration on the exit side and the inlet side of the component, respectively.

[0234] Two particle counter units (Lighthouse 2016, USA) are used simultaneously at upstream and downstream positions with respect to an article at a sub-floor location of a dilution chamber. A detection particle of di-2-ethylhexyl sebacate (DEHS) aerosol is generated using an ATM 221 aerosol generator. The flow is driven by a blower that carries the detection particles through a tunnel and ultimately into a wall-flow filter component. When the concentration upstream of the GPF reaches a steady state, the two particle counters are reset to start counting for 60 seconds, and the filtration efficiency (FE) is calculated based on the difference in the total particle count of 0.3 μm and above. The pressure drop (dP) measured by pressure gauges located upstream and downstream of the article is also recorded at a fixed flow rate of 51 Nm 3 / hr.

[0235] Pre - test loading. During pre-test canning, the article is wrapped in ceramic fiber felt material and then placed in a metal can. The article, felt, and can assembly are heated in an oven to 650 °C and held at 650 °C for a period of time. The felt expands to help hold the article in place within the can. When the felt expands, it "pops" within the can, positioning the article in place, and this process is called felt pop. The duration of pre-test canning is selected based on subsequent tests conducted.

[0236] Post - test cleaning. After conducting the test, the following steps are completed to achieve post-test cleaning of the article. The article, felt, and can assembly are placed in an oven at 650 °C and held at 650 °C for a period of time, typically about 6 hours, such that the soot loaded into the article burns out from the article.

[0237] Clean filtration efficiency

[0238] As used herein, the "clean filtration efficiency" of a honeycomb body or a filter article refers to a new or regenerated honeycomb body that does not contain any measurable soot load. In an embodiment, the clean filtration efficiency of the honeycomb body or the filter article is greater than or equal to 70%, such as greater than or equal to 80%, or greater than or equal to 85%. In other embodiments, the initial filtration efficiency of the honeycomb body or the filter article is greater than 90%, such as greater than or equal to 93%, or greater than or equal to 95%, or greater than or equal to 98%.

[0239] As used herein, a "clean filtration efficiency test" refers to testing an article as follows.

[0240] Six hours after pre-test canning, an air stream is supplied through a blower upstream of the article at a gradually increasing rate, and the clean pressure drop across the filter is measured using a differential pressure sensor / pressure gauge at room temperature (about 25 °C). The flow rate of the air stream is gradually increased in 10-step increments from 25.5 m 3 / h to 356.8 m 3 / h, where with each new step, the flow rate is maintained for one minute. The increment for each step is in the range of approximately 8 to 68 m 3 / h. Next, an air stream containing soot particles with a concentration of 8 mg / m 3 and a flow rate of 22.5 m 3 / h is introduced upstream of the filter for 45 minutes. Soot with a particle size of approximately 110 nm is generated from a commercially available propane burner. The clean filtration efficiency at 30 °C is determined by measuring the difference between the number of particles introduced to the article before and after exposure to the flow conditions and the number of particles leaving the article. After measuring the clean filtration efficiency, a 6-hour post-test cleaning is performed.

[0241] Soot Loading Pressure Drop Test

[0242] After 6 hours of pre-test canning, soot is loaded into the article, where at approximately 25 °C, the exhaust gas flow rate upstream of the assembly is incremented in 10 steps from 25.5 m 3 / h to 356.8 m 3 / h, where with each new step, the flow rate is maintained for one minute. The increment for each step is in the range of approximately 8 - 68 m 3 / h. The soot loading amount increases from 0 g / L to 3 g / L. After the filter is loaded with soot, the soot loading pressure drop across the filter is measured using a differential pressure sensor / pressure gauge at room temperature (approximately 25 °C). After measuring the soot loading pressure drop, a 6-hour post-test cleaning is performed.

[0243] Examples 1 - 2 and Example A

[0244] Measure the aggregate size using different liquid media. Table 3 lists the different liquid media tested, the corresponding particle dispersants, and the resulting aggregate sizes.

[0245] Table 3. Organic-based Suspensions

[0246] Sample number Liquid medium Particle dispersant Volume - based D50 Example A (comparison) Ethanol Triethanolamine 0.96 μm Example 1 Methanol Triethanolamine 0.82 μm Example 2 Acetone Vinyltrimethoxysilane 0.69 μm

[0247] Figures 12 - 14 SEM photos showing the samples prepared according to Example A and Examples 1 - 2 are provided. The average aggregate size is measured, and the volume-based D50 of the aggregates in the ethanol case, methanol case, and acetone case are 0.96 μm, 0.82 μm, and 0.69 μm, respectively. Between the different solvents, the basic microstructure of the aggregates is similar, but the sizes are different.

[0248] Table 4 provides the relationship between the filtration efficiency (FE) and the loading (g / L) measured at 0.3 μm filtration performance for Example A and Examples 1 - 2. Due to the smaller aggregate size, the filter articles prepared with methanol - based and acetone - based suspensions have a higher FE at the same loading than the filters prepared with ethanol - based suspension (baseline or reference) (in other words, for the same FE, the loading is lower). The suspension stabilities of the three suspensions are all quite good after standing for 24 hours. This indicates that: (1) the dispersants selected for different solvents perform well; (2) the differences in the loading - FE relationships among the different solvents shown in Table 4 are not caused by the suspension stability, but mainly by the differences in the solvent properties.

[0249] Table 4. Filtration Efficiency

[0250]

[0251]

[0252] Examples 3 and Example B

[0253] Measure the aggregate size using different liquid media. Table 5 lists the different liquid media tested, the corresponding particle dispersants, and the resulting aggregate sizes.

[0254] Table 5. Water - based Suspensions

[0255] Sample number Liquid medium Particle dispersant Volume - average particle size Example B (comparison) Water (only) Acetic acid 1.56 μm Example 3 50% water and 50% ethanol Acetic acid 0.97 μm

[0256] Figures 15 - 16 SEM photos showing the samples prepared according to Example B and Example 3 are provided. The particles in the case of 50% water / 50% ethanol have an average particle size of 0.97 μm, which is smaller than the particle size prepared with pure water suspension (1.56 μm).

[0257] Table 6 provides the relationship between the filtration efficiency (FE) and the loading (g / L) at 0.3 μm filtration performance for Example B and Example 3. Due to the smaller aggregate size, the filter articles prepared with 50% water / 50% ethanol suspension have a higher FE than the filters prepared with pure water suspension. The suspension stabilities of the three suspensions are all quite good after standing for 24 hours. No signs of sedimentation are observed by visual inspection.

[0258] Table 6. Filtration Efficiency

[0259] Sample number Liquid medium Loading amount (g / L) 0.3 μm FE (%) Example B (comparison) Water (only) 2.78 73.7 2.86 83.4 5.00 93.1 Example 3 50% water and 50% ethanol 2.51 79.7 2.54 93.9 5.15 99.0

[0260] It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments described herein without departing from the spirit and scope of the claimed subject matter. Accordingly, this specification is intended to cover modifications and variations of the various embodiments described herein, provided that these modifications and variations fall within the scope of the appended claims and their equivalents.

Claims

1. A method for applying a surface treatment to a packed honeycomb body, the honeycomb body comprising a honeycomb structure having a plurality of axially porous walls, the plurality of axially porous walls defining a plurality of axial channels in the axial direction, the method comprising: Atomizing a dispersion of inorganic material particles into liquid-particle-dispersant droplets, the liquid-particle-dispersant droplets comprising: a liquid medium comprising methanol, acetone, hexane, or a combination thereof; a particle dispersant comprising triethanolamine, triethoxyvinylsilane, vinyltrimethoxysilane, 5-hexenyltrimethoxysilane, or a combination thereof; and the particles; Evaporate at least substantially all of the liquid vehicle from the droplets to form agglomerates of the particles; And Depositing the agglomerates in the packed honeycomb body; Wherein the deposited agglomerates are disposed on the porous walls, or in the porous walls, or on and in the porous walls.

2. The method according to claim 1, the method further comprising atomizing an adhesive together with the dispersion such that the droplets are liquid-particle-dispersant-adhesive droplets, and the agglomerates further comprise the adhesive.

3. The method according to claim 1 or 2, wherein when the liquid medium comprises the methanol, the particle dispersant comprises the triethanolamine; or when the liquid medium comprises the acetone, the particle dispersant comprises the triethoxyvinylsilane or the vinyltrimethoxysilane; or when the liquid medium comprises the hexane, the particle dispersant comprises the 5-hexenyltrimethoxysilane.

4. The method according to any one of claims 1 to 3, wherein the atomizing further comprises supplying a suspension of the particles, the liquid medium, and the particle dispersant.

5. The method according to any one of claims 1 to 4, wherein the particles are mixed with the liquid medium and the particle dispersant to form a liquid-particle-dispersant stream, and the liquid-particle-dispersant stream is directed into an atomizing nozzle.

6. The method according to claim 5, wherein the liquid-particle-dispersant stream is mixed with an atomizing gas through the atomizing nozzle.

7. The method according to any one of claims 1 to 6, wherein the droplets are atomized and transported to the packed honeycomb body through a gaseous carrier stream.

8. The method according to any one of claims 1 to 7, wherein depositing the agglomerates in the packed honeycomb body comprises filtering the agglomerates from the gaseous carrier stream with the porous walls of the packed honeycomb body.

9. The method according to claim 7 or 8, wherein the carrier gas is substantially free of the liquid medium when entering the chamber of the conduit.

10. The method according to any one of claims 1 to 9, wherein for a given set of operating conditions, the agglomerates comprise an average particle size (D 50 ) is smaller than the average particle size (D) of the comparative agglomerates. 50 ), the comparative agglomerates were formed by using the given set of operating conditions but using ethanol as the liquid vehicle.

11. A method for applying a surface treatment to a packed honeycomb body, the honeycomb body comprising a honeycomb structure having a plurality of axially porous walls, the plurality of axially porous walls defining a plurality of axial channels in the axial direction, the method comprising: Atomize a dispersion of inorganic material particles into liquid - particle - dispersant - binder droplets, the liquid - particle - dispersant - binder droplets consisting essentially of: A liquid medium comprising methanol, acetone, hexane, or a combination thereof, a particle dispersant, an adhesive, and the particles; Evaporating at least substantially all of the liquid medium from the droplets to form agglomerates of the particles; And Deposit the agglomerates in the packed honeycomb body; wherein the deposited agglomerates are disposed on the porous walls, or in the porous walls, or on and in the porous walls.

12. The method according to claim 11, wherein the particulate dispersant comprises: triethanolamine, triethoxyvinylsilane, vinyltrimethoxysilane, 5-hexenyltrimethoxysilane, or a combination thereof.

13. The method according to any one of claims 11 to 12, wherein the atomization further comprises supplying a suspension of the particles, the liquid medium, the binder, and the particulate dispersant.

14. The method according to any one of claims 1 to 13, wherein the particles are mixed with the liquid medium, the particulate dispersant, and the binder to form a liquid - particle - dispersant - binder stream, and the liquid - particle - dispersant - binder stream is directed into an atomizing nozzle.

15. The method according to claim 14, wherein the liquid - particle - dispersant - binder stream is mixed with an atomizing gas through the atomizing nozzle.

16. The method according to claim 11, wherein the droplets are atomized and transported to the packed honeycomb body through a gaseous carrier stream.

17. The method according to claim 16, wherein depositing the agglomerates in the packed honeycomb body comprises filtering the agglomerates from the gaseous carrier stream with the porous walls of the packed honeycomb body.

18. The method according to claim 16 or 17, wherein the carrier gas is substantially free of the liquid medium when entering the chamber of the conduit.

19. The method according to any one of claims 11 to 18, wherein for a given set of operating conditions, the volume-based average particle size (D 50 ) of the agglomerates is less than the comparative volume-based average particle size (D 50 ) of comparative agglomerates formed by a method using the given set of operating conditions but using only ethanol as the liquid medium.

20. The method according to any one of claims 1 to 19, wherein at least some of the agglomerates adhere to the porous walls.

21. A filtration article prepared by the method according to any one of the preceding claims, the filtration article comprising a filtration efficiency of greater than or equal to 95.0% and a loading of deposited agglomerates of less than or equal to 6 grams of deposited agglomerates per liter of the honeycomb filter body.

22. The filtration article according to claim 21, wherein the filtration efficiency is greater than or equal to 99.0%.

23. The filtration article according to claim 21, wherein the loading of the deposited agglomerates is greater than or equal to 2 grams of deposited agglomerates per liter of the honeycomb filter body.

24. The filtration article according to claim 23, wherein the loading of the deposited agglomerates is less than or equal to 3 grams of deposited agglomerates per liter of the honeycomb filter body.

25. A method of applying a surface treatment to a packed honeycomb body, the honeycomb body comprising a honeycomb structure having a plurality of axial porous walls that define a plurality of axial channels in an axial direction, the method comprising: Atomizing a dispersion of inorganic material particles into liquid - particle - dispersant droplets, the liquid - particle - dispersant droplets comprising: a liquid medium comprising water and one or more solvents having a boiling point lower than that of the water, a particulate dispersant, and the particles; Evaporate at least substantially all of the liquid vehicle from the droplets to form agglomerates of the particles; and Deposit the agglomerates in the packed honeycomb body; wherein the deposited aggregates are disposed on the porous wall, or in the porous wall, or both on and in the porous wall.

26. The method according to claim 25, the method further comprising atomizing an adhesive together with the dispersion such that the droplets are liquid-particle-dispersant-adhesive droplets and the aggregates further comprise the adhesive.

27. The method according to claim 25 or 26, wherein the one or more solvents comprise ethanol, methanol, acetone, hexane, or a combination thereof.

28. The method according to claim 25, wherein the particulate dispersant comprises acetic acid, triethanolamine, triethoxyvinylsilane, vinyltrimethoxysilane, and / or 5-hexenyltrimethoxysilane.

29. The method according to claim 25, wherein the atomizing further comprises supplying a suspension of the particles, the liquid medium, and the particulate dispersant.

30. The method according to claim 25, wherein the particles are mixed with the liquid medium and the particulate dispersant to form a liquid-particle-dispersant stream and the liquid-particle-dispersant stream is directed into an atomizing nozzle.

31. The method according to claim 30, wherein the liquid-particle-dispersant stream is mixed with an atomizing gas through the atomizing nozzle.

32. The method according to claim 25, wherein the droplets are atomized and transported to the packed honeycomb body by a gaseous carrier stream.

33. The method according to claim 32, wherein depositing the aggregates in the packed honeycomb body comprises filtering the aggregates from the gaseous carrier stream with the porous wall of the packed honeycomb body.

34. The method according to claim 31 or 32, wherein the carrier gas is substantially free of the liquid medium when entering the chamber of the conduit.

35. The method according to any one of claims 25 to 34, wherein for a given set of operating conditions, the volume-based average particle size (D 50 ) of the agglomerates is less than the comparative volume-based average particle size (D 50 ) of comparative agglomerates formed by a method using the given set of operating conditions but only water as the liquid medium.

36. The method according to any one of claims 25 to 35, wherein at least some of the aggregates adhere to the porous wall.

37. A filtration article prepared by the method according to any one of claims 25 to 36, the filtration article comprising a filtration efficiency of greater than or equal to 94.0% and a loading of deposited aggregates of less than or equal to 6 grams per liter of the honeycomb filter body disposed within the honeycomb filter body.

38. The filtration article according to claim 37, wherein the filtration efficiency is greater than or equal to 98.0%.

39. The filtration article according to claim 37, wherein the loading of the deposited aggregates is greater than or equal to 2 grams of deposited aggregates per liter of the honeycomb filter body.

40. The filtration article according to claim 39, wherein the loading of the deposited aggregates is less than or equal to 5.5 grams of deposited aggregates per liter of the honeycomb filter body.

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