mixture of inorganic solids

Abstract

The present invention relates to a mixture comprising at least a first group P1 of inorganic solids with a volume mean diameter VAD1 and a second group P2 of inorganic solids with a volume mean diameter VAD2, the VAD2 / VAD1 ratio being between 0.10 and 0.60 (boundary values ​​included). The invention also relates to the use of said mixture for catalytic reactions or separation or drying operations on gases and / or liquids.

Description

Technical Field

[0001] The present invention relates to the field of zeolite aggregates, and more specifically to the floor of zeolite aggregates.

Background Art

[0002] Today, the industry widely uses zeolite aggregates in various fields, such as gas or liquid separation, purification, drying, and catalytic reactions. In these various techniques of separation, purification, drying, or other catalytic reactions, the liquid or gas is brought into contact with the zeolite aggregates for a longer or shorter time. The techniques widely used today utilize a bed of aggregates through which the liquid or gas to be treated passes. These beds of aggregates are mostly filled in columns, tubes, cartridges, or other equivalent containers, enabling the entry of the liquid or gas to be treated and the discharge of the liquid or gas after treatment. Further, these containers must be able to withstand a more or less significant pressure inherent in the process used.

[0003] Zeolite aggregates are typically particles having sizes that can range from dozens of nanometers to dozens of millimeters, and actually even several hundreds of millimeters. However, in order to further improve the efficiency and profitability of industrial equipment, it is desirable to densify the bed of zeolite aggregates in order to make available the maximum amount of zeolite aggregates in the smallest possible space, that is, there are problems of repetition in the methods and techniques used to fill the containers in order to densify the bed of zeolite aggregates.

[0004] To date, various processes or methods aimed at densifying such beds of zeolite aggregates are already known. The common objective targeted is better occupancy of the volume containing the zeolite aggregates in order to maximize the amount of solid, which should be carried out as homogeneously and uniformly as possible in a reproducible manner without sacrificing the filling time. In most cases, these are "mechanical" devices and processes well known to those skilled in the art, for example, - As described in reference US2655273, the rain effect across the entire cross-section of this chamber ensures a homogeneous distribution of particles within the chamber. - As in reference FR2288560A1, the particles are dispersed using compressed air in the fixed parts of the equipment. - In particular, as described in references FR2087890, FR2153380 and FR2319427A1, a rotating device for directly dispersing particles, - A mobile device comprising a shaft rotationally driven by a motor, as described in references EP007854A1 and EP116246A1, and several stages of flexible deflection elements such as strips.

[0005] More specifically, among these devices known to those skilled in the art, sock filling consists of manually pouring solid particles using a flexible conduit called a “sleeve” or “sock.” Accordingly, patent application US2020353434A1 describes a novel sock system for sock filling, which can take a helical shape to restrict the movement of the solid and thus prevent its degradation.

[0006] Furthermore, other "high-density" filling techniques are described in the following literature. - The Catapac(R) process is described in detail, enabling the achievement of a filling density at least 10% higher than that of the sock-type fillings described above (FR2721900). - Currently known as Densicat(R), we teach a dense packing process and combine devices and processes for packing divided solids into containers, particularly in the form of beads, particles, cylinders, etc., into chemical or electrochemical, petroleum or petrochemical type fixed beds, as indicated by EP0769462A1 and WO2006013240A1.

[0007] More recently, increasingly sophisticated devices have enabled the loading and unloading of zeolite aggregates, as shown, for example, in literature CN111634681A and US2021146326A1, which describe loading and unloading devices for adsorbents having highly specific supply systems.

[0008] In connection with, or as an alternative to, these mechanical filling devices or processes, there are also methods that use lubricants in solid form. These methods are particularly used in the pharmaceutical, cosmetics, food processing, and petrochemical industries with the aim of improving the fluidity of mixtures of zeolite crystals or zeolite aggregates. This is because fluidity is a crucial property for many processes, for example, if these crystals or aggregates must pass through a feed hopper. Therefore, to ensure a flow that is as fluid as possible and yields tablets of homogeneous weight, most pharmaceutical processes today incorporate a preliminary step of mixing with a lubricant. The latter is distributed on the surface of the crystals or aggregates and thus improves their fluidity.

[0009] To illustrate this technology, for example, one can refer to application WO2019120938A1, which describes a process of filling a chamber with solid particles that have been pre-treated. This pre-treatment consists of mixing the solid particles with at least one solid lubricant selected from saturated fatty acids having 14 or more carbon atoms, their metal salts, esters, fatty alcohols having 14 or more carbon atoms, linear n-alkanes having 16 or more carbon atoms in solid form, fumaric acid, talc, and sodium stearyl fumarate, before filling the chamber. The lubricant is introduced at ambient temperature in a content between 0.01% by weight and 1% by weight relative to the total weight of the mixture of solid particles and lubricant.

[0010] Japanese Patent US7927555B2 describes, as part of its process for filling catalyst particles containing certain liquids, such as water or organic compounds having a boiling point above 100°C at 1 atmosphere.

[0011] However, these technologies, which utilize solid or liquid lubricants, have the drawback of requiring a step to remove the lubricant after particle filling. This is because the lubricant may reduce the performance or efficiency of the adsorbent or catalyst. Furthermore, this technology may raise concerns regarding the presence of residual organic compounds, which can lead to coking, deposits, clogging, and the like.

[0012] Other methods for packing particles are presented, in particular in document WO2015107322, in which catalyst particles are packed radially into a column on the one hand, and smaller sized particles are packed axially into the same column on the other hand. Patent EP0891802B1 provides a particle packer intended for packing particles into a container to form a particle bed having an outer concentric layer and an inner concentric layer, wherein the particles of the inner and outer layers differ in both particle size and composition.

[0013] These techniques, which may be described as "mechanical," have the drawback of requiring relatively complex devices to fill certain groups of particles in one particular configuration and other groups of particles in another particular configuration. [Prior art documents] [Patent Documents]

[0014] [Patent Document 1] U.S. Patent No. 2,655,273 [Patent Document 2] French Patent Application Publication No. 2288560 [Patent Document 3] French Patent Application Publication No. 2087890 [Patent Document 4] French Patent Application Publication No. 2153380 [Patent Document 5] French Patent Application Publication No. 2319427 Specification [Patent Document 6] European Patent Application Publication No. 007854 [Patent Document 7] European Patent Application Publication No. 116246 [Patent Document 8] U.S. Patent Application Publication No. 2020 / 353434 [Patent Document 9] French Patent No. 2721900 [Patent Document 10] European Patent Application Publication No. 0769462 [Patent Document 11] International Publication No. 2006 / 013240 [Patent Document 12] Chinese Patent Application Publication No. 111634681 [Patent Document 13] U.S. Patent Application Publication No. 2021 / 146326 [Patent Document 14] International Publication No. 2019 / 120938 [Patent Document 15] U.S. Patent No. 7927555 [Patent Document 16] International Publication No. 2015 / 107322 [Patent Document 17] European Patent No. 0891802 [Summary of the Invention] [Problems to be Solved by the Invention]

[0015] The object of the present invention is to overcome the above problems encountered by known filling methods in the prior art.

[0016] Therefore, a first object is to provide means that enable optimized filling at high density into a column intended to receive a container of solid particles, such as a zeolite aggregate or catalyst particles. Another object is to prevent filling of the front slope, or at least prevent filling of the front slope exceeding 10%.

[0017] Another objective is to increase the amount of active phase in the bed of the zeolite aggregate or catalyst relative to a given volume, in order to further improve the efficiency of the zeolite aggregate or catalyst, respectively. [Means for solving the problem]

[0018] The above objectives are achieved, in whole or in part, by the present invention as described below. Further objectives will become apparent in the description of the present invention as described below.

[0019] This is because the inventors have discovered a simple, economical, and effective means that can increase the density of a set of particles packed in a container, that is, make them more dense, and in particular in catalytic processes or adsorption or separation processes, preferably in adsorption separation processes, not only the bed of zeolite aggregates (also called molecular sieves), fixed beds and simulated moving beds commonly used, but also the bed of catalyst particles.

[0020] Accordingly, according to the first aspect, the present invention relates to a mixture comprising at least a first group P1 of inorganic solids having a volume-average diameter VAD1 and a second group P2 of inorganic solids having a volume-average diameter VAD2, wherein the VAD2 / VAD1 ratio is between 0.10 and 0.60 (including boundary values), preferably between 0.15 and 0.55 (including boundary values), advantageously between 0.20 and 0.50 (including boundary values), and more specifically between 0.25 and 0.50 (including boundary values). [Modes for carrying out the invention]

[0021] In one embodiment of the present invention, the inorganic solids of group P1 exhibit a volume-average diameter VAD1 between 0.4 mm and 5 mm, preferably between 0.4 mm and 2.5 mm, more preferably between 0.4 mm and 1 mm, and very preferably between 0.4 mm and 0.8 mm (including boundary values).

[0022] The mixture according to the present invention generally, preferably, contains a group of inorganic solids P2 in an amount that does not cause substantial variation in the volume-average diameter (VADm) of the mixture compared to VAD1. More specifically, the mixture according to the present invention exhibits a VADm / VAD1 ratio greater than 0.85, preferably greater than 0.88, and more preferably greater than 0.90.

[0023] In a preferred embodiment of the present invention, the amount of inorganic solids of the second group P2 corresponds to a maximum of 25% by weight, preferably a maximum of 15% by weight, for example, 0.5% to 25% by weight, and more preferably 1% to 15% by weight (including boundary values), relative to the combined P1+P2 inorganic solids.

[0024] In general, with respect to the above-mentioned ratio VAD2 / VAD1, the inorganic solids of group P2 exhibit a volume-average diameter VAD2 of less than 2 mm, preferably less than 1 mm, more preferably less than 0.5 mm, more specifically less than 0.4 mm, and typically less than 0.3 mm. According to a preferred embodiment, the volume-average diameter VAD2 is greater than 0.05 mm, and more preferably greater than 0.1 mm. Therefore, according to yet another preferred embodiment, the volume-average diameter VAD2 is between 0.05 mm and 2 mm, preferably between 0.05 mm and 1 mm, more preferably between 0.05 mm and 0.5 mm, more specifically between 0.1 mm and 0.4 mm, and typically between 0.1 mm and 0.3 mm (including boundary values).

[0025] In a particularly preferred embodiment of the present invention, the latter relates to a mixture of inorganic solids comprising at least two groups P1 and P2, as precisely defined.

[0026] The inorganic solids of groups P1 and P2 may have any properties. However, the present invention is particularly suited to inorganic solids selected from adsorbents in general, such as zeolites, alumina, silica gel, and catalysts, more specifically from zeolite aggregates, also called molecular sieves, and solid catalysts, whether in the form of powders, beads, crushed materials, extruded products, spun yarns, molded articles, or any other form known to those skilled in the art, preferably in the form of beads. Preferably, zeolite aggregates, also called molecular sieves, are preferred, and among them are aggregates of zeolite crystals having at least one binder, which is organic or inorganic, preferably inorganic, such as clay or a mixture of clays.

[0027] In preferred embodiments of the mixture of the present invention, the inorganic solids of groups P1 and P2 have the same chemical properties, or at least are sufficiently similar, i.e., the two groups contribute to the same desired objective during use of the mixture. According to a completely preferred embodiment, the inorganic solids of groups P1 and P2 have the same chemical properties.

[0028] While we do not wish to be bound by theory, it can be considered that the inorganic solids of groups P1 and P2 act as "lubricants" to each other, resulting in a reduction of free space between the inorganic solid particles compared to what is observed in a single group of inorganic solids P1 or a single group of inorganic solids P2, and therefore, a densification of the mixture present in the container, in other words, an increase in volume.

[0029] The present invention is particularly suitable for zeolite aggregates and solid particles of catalysts.

[0030] According to yet another preferred embodiment of the present invention, the inorganic solids of group P2 exhibit an average roundness of more than 60%, more preferably more than 80%, and most preferably more than 90%.

[0031] The average roundness, expressed as a percentage, is calculated from the moment of the distribution of circles inscribed within the particle and tangent to points on the particle's contour, following complex filtering, as shown in reference WO2008152319. This represents the variation in the particle's radius of curvature and reflects the maturity of the solid in the wear process. Gentle ridges are more important than very prominent ridges. The closer the sphericity is to perfect, the closer the roundness is to 100%.

[0032] In one embodiment, the mixture according to the present invention advantageously exhibits a floor crushing strength typically of several hundred kPa to several tens of MPa, generally between 0.3 MPa and 3.2 MPa, preferably between 0.3 MPa and 2.5 MPa. Methods for measuring floor crushing strength and other analytical methods will be described later in the specification.

[0033] The mixture according to the present invention is particularly well suited to adsorbent zeolite aggregates, whether molecular sieves or catalyst particles. The mixture according to the present invention is especially well suited to solid particles of zeolite aggregates.

[0034] In a preferred embodiment, the mixture of the present invention comprises or consists of an inorganic solid which is an aggregate of zeolite crystals, which is well known to those skilled in the art and has been widely described in the scientific and patent literature.

[0035] As a non-limiting example, the zeolite aggregates contained in the mixture of the present invention are aggregates of zeolite crystals, and the zeolite is selected from LTA type zeolites, preferably 3A, 4A and 5A zeolites, FAU type zeolites, preferably X, LSX, MSX or Y type zeolites, MFI type zeolites, preferably ZSM-5 type zeolites and silicalite, zeolite P, SOD type zeolites (such as sodalite), MOR type zeolites, CHA type zeolites (such as chabazite), HEU type zeolites (such as clinoptilolite), homologs having hierarchical porosity, and mixtures containing any proportion of two or more of these.

[0036] With regard to the requirements of the present invention, aggregates of zeolites selected from LTA type zeolites, preferably 3A, 4A and 5A zeolites, FAU type zeolites, preferably X, LSX, MSX or Y type zeolites, zeolite P, SOD type zeolites (such as sodalite), MOR type zeolites, CHA type zeolites (such as chabazite), HEU type zeolites (such as clinoptilolite), homologs having hierarchical porosity, and mixtures containing any proportion of two or more of these are preferred.

[0037] The zeolites described above may be natural, artificial, or synthetic, or natural after reduction, modified, or synthetic. Zeolites generally contain one or more types of cations to ensure electronic neutrality. The cations naturally present in zeolites or after one or more cation exchanges are well known to those skilled in the art. Non-limiting examples of such cations include hydrogen cations, alkali metal cations, alkaline earth metal cations, metal cations from Group VIII, IB, and IIB, and mixtures of two or more of these. Common examples of cations include lithium, potassium, sodium, barium, calcium, silver, copper, zinc cations, and mixtures of two or more of these in any proportion.

[0038] A particularly preferred mixture according to the present invention includes, as a non-limiting example, a first group P1 of zeolite aggregates and a second group P2 of zeolite aggregates, wherein the zeolite aggregates are identical or different and selected from aggregates of zeolite LTA (such as 3A, 4A, or 5A), X, LSX, MSX, and Y.

[0039] Specific examples of the mixtures according to the present invention, to name only a few, include mixtures of zeolite LTA aggregates, for example, zeolite 3A and zeolite 4A, or mixtures of zeolite 4A aggregates and zeolite 5A aggregates, mixtures of zeolite LSX aggregates and zeolite X aggregates, mixtures of zeolite MSX aggregates and zeolite X aggregates, mixtures of zeolite LSX aggregates and zeolite MSX aggregates, mixtures of zeolite X aggregates and zeolite Y aggregates, and mixtures of zeolite 4A aggregates and zeolite X aggregates.

[0040] According to preferred embodiments of the present invention, the inorganic solids of groups P1 and P2 have the same properties, that is, as non-limiting examples, they form a mixture selected from the group including a mixture of zeolite aggregates based on zeolite LTA (e.g., a mixture of zeolite aggregates based on zeolite 3A, a mixture of zeolite aggregates based on zeolite 4A), a mixture of zeolite aggregates based on zeolite LSX, a mixture of zeolite aggregates based on zeolite MSX, a mixture of zeolite aggregates based on zeolite X, a mixture of zeolite aggregates based on zeolite Y, a mixture of zeolite aggregates based on zeolite MFI, a mixture of zeolite aggregates based on zeolite EMT, and the like.

[0041] According to another embodiment of the present invention, the inorganic solids of groups P1 and P2 have different properties, and, as a non-limiting example, to name only a part of them, form a mixture selected from the group including a mixture of zeolite X-based zeolite aggregates and zeolite LSX-based aggregates, a mixture of zeolite X-based zeolite aggregates and zeolite MSX-based aggregates, a mixture of zeolite MSX-based zeolite aggregates and zeolite LSX-based aggregates, a mixture of zeolite X-based zeolite aggregates and zeolite Y-based aggregates, a mixture of zeolite X-based zeolite aggregates and zeolite 4A-based aggregates, a mixture of zeolite 4A-based zeolite aggregates and zeolite 5A-based aggregates, and the like.

[0042] The mixture according to the present invention can be prepared by any means well known to those skilled in the art, for example, by simply mechanically mixing the inorganic solids of groups P1 and P2 using a conventional agitator, such as a blade agitator, or through a supply hopper having a common filling conduit, while directly filling the mixture into a desired container.

[0043] The mixture according to the present invention makes it possible to fully or partially address the shortcomings faced in the prior art, and more particularly, to improve the packing density of a container having inorganic solid particles as defined above. Thus, the mixture according to the present invention makes it possible to increase the density of a bed of solid inorganic particles while avoiding reliance on organic lubricants that may be difficult to remove and / or at least partially remain in the mixture. As described above, in the mixture according to the present invention, the lubricating effect is observed by a specific ratio of the volume-average diameters of groups P1 and P2.

[0044] According to a preferred embodiment, the mixture according to the present invention enables an increase in the packing density of group P1 by 2%, preferably 5%, more preferably 7%, and advantageously 10% or more.

[0045] Another advantage of the mixture of the present invention lies in the fact that the pre-mixing step can be eliminated by simultaneously filling the container with inorganic solids of groups P1 and P2. Due to the observed lubricating effect, the inorganic solid particles fill the container in a dense manner without relying on other alternating filling techniques, radial / axial or otherwise, and without relying on complex equipment intended to homogeneously fill the container, as is often seen in the prior art.

[0046] Therefore, filling a container with the mixture according to the present invention can be done directly or by simultaneous filling as described above, starting from a mixture of inorganic solid particles of groups P1 and P2. In some cases, if desired, one or more auxiliary means can be used to assist in high-density filling of the mixture according to the present invention in order to further improve the homogeneous distribution of the mixture according to the present invention in a desired container, and such means are well known to those skilled in the art and can be selected from, in non-limiting examples, means comprising a vibrating means, a flexible sleeve, a blade, and the like. However, such means are generally undesirable, but the mixture according to the present invention exhibits a completely unexpected fluidity, which as a result facilitates filling, particularly on the floor, in a manner not yet observed in the techniques described in the prior art.

[0047] Furthermore, the mixtures according to the present invention having groups P1 and P2 with VAD2 / VAD1 ratios as claimed were observed to have a positive effect on mass transfer in application (reduction in mass transfer zone compared to that observed for group P1). Specifically, in some cases, a reduction in floor porosity could be observed without a significant increase in pressure drop.

[0048] The mixture according to the present invention is particularly suitable for filling containers in an optimal manner, i.e., with an optimized amount of inorganic solid particles per unit volume. This effect of optimizing the amount per unit volume, i.e., "densification," is due in particular to the excellent fluidity of the mixture according to the present invention. This property can be observed for all sizes of inorganic solids, as shown above.

[0049] Furthermore, it was observed that the improved fluidity achieved by the specific VAD1 / VAD2 ratio described above prevented deterioration often observed during filling of the mixture according to the present invention, such as deterioration, wear, and crushing, particularly deterioration when passing through the filling hopper.

[0050] The mixture according to the present invention also has the advantage of being suitable for containers of all sizes, whether they are columns, tubes, reactors, etc. The aforementioned good fluidity properties of the mixture according to the present invention ensure high density during filling and very good homogeneity of the filling, making it possible to substantially optimize the fluid dynamics of the flow in the target application.

[0051] Therefore, the mixtures according to the present invention find applications in numerous fields of application, whether in static or dynamic modes, for example, but not limited to, separation of gases and / or liquids, drying operations for gases and / or liquids, separation of organic molecules such as hydrocarbons in the gas phase and / or liquid phase, and catalytic reactions in the gas phase and / or liquid phase.

[0052] The following examples illustrate the present invention without limiting the scope of the invention as defined by the appended claims. The physical properties of aggregates according to the present invention were evaluated by methods known to those skilled in the art, and the main ones are listed below.

[0053] <Measurement method> <Loss on ignition (LOI)> As described in standard NF EN 196-2 (April 2006), the ignition loss is measured in an oxidizing atmosphere by calcining the sample in air at a temperature of 950°C ± 25°C. The standard deviation of the measurement is less than 0.1%.

[0054] <density> The bulk density of the zeolite aggregate material according to the present invention is measured according to the size of the aggregate material being tested, as described in standard DIN 8948 / 7.6 or standard ASTM D4164.

[0055] To determine the packing density, a predetermined amount of the agglomerate bead mixture is placed in a 250 ml graduated cylinder. The test specimen is placed in a tamping system (a JEL STAV 2003 Stampf type impact system) and subjected to an impact of 2400 J for 10 minutes. The acquisition of a constant volume is confirmed by adding another 2 minutes of tamping. The packing density (or packed density) is then calculated by measuring the weight and occupied volume of the mixture in the test specimen. Before performing the measurement, the agglomerates are allowed to stand to recover moisture to ensure that there is no weight fluctuation during the density measurement.

[0056] To convert the density measurement back to the anhydrous value, the loss on ignition (LOI) is measured.

[0057] <Average volume diameter of particles> Using a Microtrac CamSizer(R) instrument, the volume-average diameter of inorganic solid particles is determined by analyzing the particle size distribution of an adsorbent material sample by imaging it according to the ISO 13322-2:2006 standard, using a conveyor belt that allows the sample to pass in front of the camera lens.

[0058] Next, the volume-average diameter is calculated from the particle size distribution by applying the standard ISO 9276-2:2001. The accuracy is approximately 0.01 mm for the range of volume-average diameters of solid particles that can be used in relation to the present invention.

[0059] <Measurement of roundness> For each sample tested, 10,000 particles were acquired using the Alpaga 500 Nano instrument, and elongation and roundness parameters were calculated for each particle. The mathematical tools used for these calculations were developed in the physician's theory of E. Pirard (1993, University of Liege, p. 253), entitled "Morphometrie euclidienne des figure planes. Applications a lanalyse des materiaux granulaires" (Euclidean morphometry of flat figures. Applications in the analysis of granular materials). The document entitled "The descriptive and quantiative representation of particle shape and morphology" is available under reference ISO / DIS 9276-6.

[0060] The average roundness is expressed as a percentage and, as already mentioned above, is calculated from the moment of the distribution of circles inscribed within the particle and tangent to the points of the particle's contour, following complex filtering. This represents the variation in the particle's radius of curvature and reflects the particle's maturity in the wear process. Gentle ridges are more important than very prominent ridges. The closer the particle's shape is to a perfect sphere, the closer the roundness is to 100%.

[0061] <Mechanical strength> The method selected to characterize the mechanical strength of the inorganic solid mixture of the present invention is the standard ASTM D7084-04, which allows for the determination of the crushing resistance of the solid bed. A 20 cm internal section is placed in a metal cylinder. 3 A force increasing in the stationary phase is applied to the aggregated sample via a piston.

[0062] The fine powders obtained in various static pressure phases are separated by sieving and weighed. The sieves used are suitable for aggregates smaller than 1000 μm in size. For mixtures with volume-average diameters between 500 μm and 1000 μm, between 180 μm and 500 μm, and between 50 μm and 180 μm, sieves of 200 μm, 80 μm, and 40 μm are used.

[0063] On a graph representing the cumulative weight of fine particles obtained as a function of the force applied to a floor mixture of solid particles, the crushing strength (BCS) of the floor is determined by interpolating the applied load at 0.5 wt% of the accumulated fine particles and calculating the corresponding pressure expressed in MPa, with the interpolated force relating to the surface area of ​​the internal section of the cylinder. [Examples]

[0064] [Example 1 (according to the present invention)] Two adsorbents were prepared from X-type faujasite zeolite crystals, with a number-average crystal size of 0.6 μm.

[0065] <Preparation of Adsorbent 1 (Group P1)> A homogeneous mixture is prepared, and 800 g of zeolite crystals are agglomerated in an Eirich nodulating mixer with 160 g of kaolin (expressed as a calcined equivalent) and 60 g of colloidal silica sold under the trade name Klebosol® 30N50 (containing 30 wt% SiO2 and 0.5 wt% Na2O). The stirrer is started, and water is gradually introduced until the moisture content of the mixture reaches approximately 36%. The stirrer speed is adjusted to prepare beads with an average size of approximately 0.7 mm. Aggregates larger than 1 mm and fine powders smaller than 0.315 mm are removed by sieving. The beads thus obtained are dried and then calcined under a nitrogen stream at 550°C for 2 hours (clay calcination). The volume average diameter VAD1 of the obtained beads (group P1) is 0.662 mm, and the packing density (returning to anhydrous) is 0.613.

[0066] <Preparation of Adsorbent 2 (Group P2)> A second adsorbent is prepared according to the same protocol, but the stirring speed is increased to obtain aggregates with an average size close to 0.150 mm. Subsequently, the aggregates are polished in a bowl granulator to form uniform beads. Selection by sieving is performed to obtain beads with a size between 0.08 mm and 0.180 mm. The beads are dried and then fired at 550°C for 2 hours under a flow of nitrogen (fired clay). The volume average diameter VAD2 of the obtained beads (group P2) is 0.137 mm, and the packing density (returning to anhydrous) is 0.563.

[0067] <Characteristics of the mixture of Group P1 and Group P2> Next, a mixture of groups P1 and P2 in proportions of 90% by weight of P1 and 10% by weight of P2 is prepared in a Turbula helical mixer. The VAD2 / VAD1 ratio is equal to 0.21.

[0068] The volume-average diameter (VADm) of the mixture obtained by the above method is very close to the volume-average diameter of group 1 (VAD1 = 0.662 mm), and more specifically, VADm / VAD1 = 0.87.

[0069] The packing density of the mixture was also measured, and a 10.7% increase was observed compared to the packing density observed for group 1.

[0070] This embodiment clearly demonstrates that the mixture according to the present invention enables a substantially increased packing density of group 1 while maintaining a substantially unchanged volume-average diameter.

[0071] [Example 2 (according to the present invention)] Adsorbent 3 is prepared according to the same protocol used for adsorbent 2, while varying the stirring speed, in order to obtain aggregates with an average size close to 0.20 mm. Subsequently, the aggregates are polished in a bowl granulator to form uniform beads. Selection by sieving is performed to obtain beads with a size between 0.125 mm and 0.315 mm. The beads are dried and then fired at 550°C for 2 hours under a flow of nitrogen (fired clay).

[0072] The volume-average diameter VAD2 of the obtained beads (group P2) and their packing density (returned to anhydrous) are 0.210 mm and 0.574, respectively.

[0073] <Characteristics of the mixture of Group P1 + Group P2 (adsorbent 3)> Next, a mixture of group P1 (from Example 1) and P2 (adsorbent 3 prepared above) in proportions of 90% by weight of P1 and 10% by weight of P2 is prepared in a Turbula helical mixer. The VAD2 / VAD1 ratio is equal to 0.32.

[0074] The volume-average diameter (VADm) of the mixture obtained by the above method is very close to the volume-average diameter of group 1 (VAD1 = 0.662 mm), and more specifically, VADm / VAD1 = 0.89.

[0075] The packing density of the mixture was also measured, and a 9.4% increase was observed compared to the packing density observed for group 1.

[0076] This embodiment clearly demonstrates that the mixture according to the present invention enables a substantially increased packing density of group 1 while maintaining a substantially unchanged volume-average diameter.

[0077] [Example 3 (Actual Invention)] Adsorbent 4, a new adsorbent, is prepared in the same manner as adsorbents 2 and 3 described above, while varying the stirring speed to obtain aggregates with an average size close to 0.30 mm. After passing the aggregates through a drum granulator, selection is performed by sieving to obtain beads with a size between 0.18 mm and 0.40 mm. The beads are dried and then fired at 550°C for 2 hours under a nitrogen flow (fired clay). The volume average diameter VAD2 and packing density (returned to anhydrous) of the obtained beads (group P2) are 0.318 mm and 0.606, respectively.

[0078] <Characteristics of the mixture of Group P1 + Group P2 (adsorbent 4)> Next, a mixture of group P1 (from Example 1) and P2 (adsorbent 4) in proportions of 90% by weight of P1 and 20% by weight of P2 is prepared in a Turbula helical mixer. The VAD2 / VAD1 ratio is equal to 0.48.

[0079] The volume-average diameter (VADm) of the mixture obtained by the above method is very close to the volume-average diameter of group 1 (VAD1 = 0.662 mm), and more specifically, VADm / VAD1 = 0.89.

[0080] The packing density of the mixture was also measured, and a 7.1% increase was observed compared to the packing density observed for group 1.

[0081] This embodiment clearly demonstrates that the mixture according to the present invention enables a substantially increased packing density of group 1 while maintaining a substantially unchanged volume-average diameter.

[0082] [Comparative Example 1] To obtain aggregates with an average size close to 0.45 mm, another adsorbent is prepared according to the same protocol (according to the protocols described above for adsorbents 3 and 4), while varying the stirring speed.

[0083] Next, the aggregates are polished in a drum granulator to form uniform beads. Selection by sieving is performed to obtain beads with a size between 0.40 mm and 0.50 mm. The beads are dried, and then fired at 550°C for 2 hours under a nitrogen flow (clay firing).

[0084] The volume-average diameter VAD2 of the obtained beads (group P2) and their packing density (returned to anhydrous) are 0.441 mm and 0.607, respectively.

[0085] <Characteristics of the mixture of Group P1 and Group P2 (comparative adsorbent 1)> Next, a mixture of group P1 and P2 (compound 1) in proportions of 90% by weight of P1 and 10% by weight of P2 is prepared in a Turbula helical mixer. The VAD2 / VAD1 ratio is equal to 0.67.

[0086] The volume-average diameter (VADm) value of the mixture obtained by the above method is substantially the same as the volume-average diameter (VAD1 = 0.662 mm) value of group 1, and more specifically, VADm / VAD1 = 0.97.

[0087] The packing density of the mixture was also measured, and it should be noted that there was no increase in density compared to the packing density observed for group 1, and in fact there was even a density loss of approximately 0.4%.

[0088] The values ​​obtained in Examples 1, 2, and 3, and Comparative Example 1 are summarized in Table 1 below.

[0089] [Table 1]

Claims

1. A mixture comprising at least a first group P1 of inorganic solids with a volume-average diameter VAD1 and a second group P2 of inorganic solids with a volume-average diameter VAD2, wherein the VAD2 / VAD1 ratio is between 0.10 and 0.60 (including boundary values), the inorganic solids are selected from zeolite aggregates, and the inorganic solids of the first group P1 exhibit a volume-average diameter VAD1 between 0.4 mm and 5 mm. The VADm / VAD1 ratio is higher than 0.85, where VADm represents the volume-average diameter of the mixture. The amount of inorganic solids in the second group P2 corresponds to a maximum of 25% by weight (including boundary values) of the combined P1 + P2 inorganic solids. mixture.

2. The mixture according to claim 1, wherein the inorganic solid of group P1 exhibits a volume-average diameter VAD1 between 0.4 mm and 2.5 mm.

3. The mixture according to claim 1, wherein the volume-average diameter of the inorganic solids of group P2 is less than 2 mm.

4. The mixture according to claim 1, wherein the volume-average diameter of the inorganic solids in group P2 is greater than 0.05 mm.

5. The mixture according to claim 1, wherein the inorganic solid is a zeolite aggregate, whether in the form of a powder, crushed material, extruded product, spun yarn, molded product, or any other form.

6. The mixture according to claim 1, wherein the inorganic solid is an aggregate of zeolite crystals, and the zeolite is selected from LTA type zeolite, FAU type zeolite, MFI type zeolite, zeolite P, SOD type zeolite, MOR type zeolite, CHA type zeolite, HEU type zeolite, homologs having hierarchical porosity, and mixtures of two or more of these in any proportion.

7. The mixture according to claim 1, selected from a mixture of at least a first group P1 of zeolite aggregates and a mixture of at least a second group P2 of zeolite aggregates, wherein the zeolite aggregates are the same or different, and selected from zeolite LTA (such as 3A, 4A, or 5A), X, LSX, MSX, and Y aggregates.

8. Use of the mixture according to any one of claims 1 to 7 for the separation of gases and / or liquids in static or dynamic mode, for drying operations on gases and / or liquids, for the separation of organic molecules in the gas phase and / or liquid phase, or for catalytic reactions in the gas phase and / or liquid phase.

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