Filtration aid for non-aqueous liquids

Abstract

A method for filtering non-aqueous liquids, such as biodiesel, that reduces sterol glucosides and / or saturated monoglycerides is provided. The present invention provides a filter aid material that improves the (low-temperature) performance of biodiesel by partially or completely removing vegetable impurities such as sterol glucosides and / or saturated monoglycerides through adsorption. The improved low-temperature soaking properties are obtained by using a filter aid material with certain surface properties.

Description

[Technical Field]

[0001] The present invention relates to a method for filtering non-aqueous liquids. In particular, the present invention relates to a method for filtering non-aqueous liquids such as biodiesel. [Background technology]

[0002] Identifying and utilizing economically viable renewable energy sources has been a policy objective for governments worldwide. One renewable fuel source that has been promoted and developed to date is biodiesel. Biodiesel is attractive because it has properties similar to petroleum-based diesel fuel. Because biodiesel is dependent on the price of petroleum-derived energy and its energy content-to-capital ratio is close to the break-even point, it could be a desirable alternative to wind, solar, and ethanol-derived energy. [Overview of the Initiative]

[0003] Biodiesel is generally a form of refined alkyl ester of fatty acids, commonly known as fatty acid alkyl esters (FAAEs). The production of these FAAEs is carried out by the transesterification of animal and vegetable fats and oils, or by the esterification of fatty acids containing free fatty acids (FFAs) found in degraded fats and oils. This method involves reacting triacylglycerols with an alcohol, typically methanol, in the presence of a catalyst (e.g., sodium or potassium hydroxide or methoxide), to produce a reaction called "transesterification." Alternatively, fatty acids, including those found in degraded fats or oils containing high levels of FFAs, commonly known as "yellow grease," "brown grease," or "trap grease," are reacted with an alcohol, typically methanol, in the presence of an acid, to produce a reaction called "esterification." When degraded fats and oils are used as raw materials, esterification is performed before transesterification to facilitate the conversion of fatty acids to FAAEs. Unreacted methanol from both steps is then removed by flash evaporation, allowing for reuse in subsequent esterification and / or transesterification reactions.

[0004] Biodiesel can also be obtained from triacylglycerides (also called “triglycerides”) which can be obtained from both plant and animal fat sources. Triacylglycerides can be obtained, for example, from soybean oil, rapeseed oil, palm oil, coconut oil, corn oil, cottonseed oil, mustard oil, used cooking oil, float grease from wastewater treatment plants, animal fats such as beef tallow and lard, soda oil, crude oil, “yellow grease” (i.e., animal or vegetable oils used or produced as a result of restaurants and other food establishments preparing or cooking food for human consumption, with a free fatty acid content of less than 15%), and “white grease” which is fats that are mainly derived from pork and / or other animal fats, with a maximum free fatty acid content of 4%.

[0005] However, simply carrying out esterification and / or transesterification reactions of fatty acids is not enough to produce usable biodiesel fuel. FAAEs contain impurities, can crystallize and contaminate engines, and can cause many problems for users. Therefore, regulations have been put in place to address consumers' quality assurance needs. Strict standards for commercial biodiesel have been developed by most national governments, including ASTM D6751 from ASTM International of the US government and EN 14214 from the European Union by the European Committee for Standardization.

[0006] As a result of the transesterification reaction described above, two products are produced: fatty acid alkyl esters (FAAEs) (typically fatty acid methyl esters (FAMEs)) and glycerin. The glycerin portion is separated from the FAAE portion by centrifugation or gravity sedimentation, and the resulting FAAE is often referred to as "crude biodiesel." The crude biodiesel portion consists of FAAE containing impurities that must be removed before it can be commercially sold as biodiesel. These impurities include, but are not limited to, alcohols, glycerin, soaps, residual catalysts, metals, free fatty acids, sterol glycosides, and other impurities that reduce the stability of biodiesel. Therefore, at this point in the process, FAAE cannot be commercially sold as biodiesel until appropriate specifications (e.g., ASTM D6751, EN 14214, etc.) are achieved.

[0007] In biodiesel, solid precipitation can occur at lower temperatures. The main impurities causing this undesirable precipitation are thought to include sterol glucosides and saturated monoglycerides. These precipitates can lead to filter clogging and vehicle malfunctions. This is recognized as a challenge, and biodiesel is now evaluated using ASTM D7501, also known as the "Cryogenic Immersion Test." Because directly measuring sterol glucosides and saturated monoglycerides is difficult and tends to be expensive, the industry has opted for the proven D7501 test, which characterizes the types of contaminants that cause filter clogging. [Problems that the invention aims to solve]

[0008] The object of the present invention is to provide a filter aid material that improves the (low-temperature) performance of biodiesel by partially or completely removing vegetable impurities such as sterol glucosides and / or saturated monoglycerides by adsorption. Here, the "adsorption" used herein refers to the tendency of molecules from the surrounding fluid phase to adhere to the surface of a solid. This should not be confused with the term "absorption" that occurs when molecules from the surrounding fluid diffuse into the solid, which is in contrast to the molecules from the surrounding fluid adhering to the surface of the solid.

[0009] The inventors have surprisingly found that improved low-temperature immersion properties can be obtained by using a filter aid material having certain surface characteristics.

Means for Solving the Problems

[0010] The present invention provides a method for filtering a non-aqueous liquid. More specifically, in a first aspect, the present invention includes a step of preparing a non-aqueous liquid and a step of filtering the non-aqueous liquid through a filter aid material, wherein the dispersive surface energy (γd 0.08) of the filter aid material is greater than about 32, and provides a method for filtering a non-aqueous liquid.

[0011] In a second aspect, it includes a step of preparing a non-aqueous liquid and a step of filtering the non-aqueous liquid through a filter aid material, and provides a method for filtering a non-aqueous liquid, wherein the ratio of the basic surface energy to the acidic surface energy (γ- / γ+) of the filter aid material is greater than 1.

[0012] In a third aspect, it includes a step of preparing a non-aqueous liquid and a step of filtering the non-aqueous liquid through a filter aid material, and provides a method for filtering a non-aqueous liquid, wherein the filter aid material contains perlite, is composed of perlite, or is essentially composed of perlite.

[0013] Perlite may contain expanded perlite, be composed of expanded perlite, or be essentially composed of expanded perlite.

[0014] The method according to the present invention is suitable for removing or adsorbing plant-derived impurities such as sterol glucosides and / or saturated monoglycerides from a non-aqueous liquid.

[0015] In a fourth aspect, the use of a filter aid material is provided to reduce the amount of sterol glucoside and / or saturated monoglycerides precipitated or crystallized in a non-aqueous liquid when tested according to ASTM D7501, wherein the filter aid material conforms to any one of the first, second, or third aspects of the present invention, or a combination thereof.

[0016] In a fifth aspect, the use of a filter aid material is provided to reduce the filter blocking tendency of a non-aqueous liquid, wherein the filter aid material conforms to any one or a combination thereof of the first, second, or third aspects of the present invention. The filter aid material reduces the filter blocking tendency of a non-aqueous liquid by reducing and / or minimizing the amount of sterol glucosides and / or saturated monoglycerides precipitated from the non-aqueous liquid when tested according to ASTM D7501. For example, the amount of sterol glucosides and / or saturated monoglycerides in the filtered non-aqueous liquid (e.g., biodiesel) may be less than 10 ppm.

[0017] A sixth aspect provides a method for reducing the amount of sterol glucosides and / or saturated monoglycerides in a non-aqueous liquid (e.g., biodiesel) by filtering the non-aqueous liquid through a filter aid material, wherein the filter aid material conforms to any one or a combination of the first, second, or third aspects of the present invention.

[0018] In various embodiments of the present invention following filtration, the amount of sterol glucoside and / or saturated monoglycerides in the non-aqueous liquid (e.g., biodiesel) can typically be less than about 10 ppm, e.g., less than about 9 ppm, e.g., less than about 8 ppm, e.g., less than about 7 ppm, e.g., less than about 6 ppm, less than 5 ppm, or less than 4 ppm. The level of sterol glucoside and / or saturated monoglycerides in the filtered non-aqueous liquid can be at least 1 ppm.

[0019] In various embodiments of the present invention, the filter aid material may contain, be composed of, or essentially composed of one or more of the following: biosource silica, volcanic glass, silicates, diatomaceous earth, perlite, cellulose, and silica gel. For example, the filter aid material may contain, be composed of, or essentially composed of perlite, and in some examples, the perlite may contain, be composed of, or essentially composed of expanded perlite. The filter aid material may exist in composite or non-composite forms.

[0020] Non-aqueous liquids may consist of, essentially consist of, or contain biodiesel. Biodiesel may exist in combination with one or more other liquids, for example, as a combination or mixture with non-biodiesel or conventional diesel (petroleum-based diesel fuel).

[0021] In various embodiments of the present invention, the method may include preparing a non-aqueous liquid for filtration, mixing a filter aid material with the non-aqueous liquid as a body feed, and filtering the non-aqueous liquid through a filtration structure to separate the filter aid material from the non-aqueous liquid. The filter aid material is as shown in the filter aid material used in various embodiments of the present invention. The filtration structure may also contain the filter aid material for use according to the present invention. For example, the filtration structure may be coated with the filter aid material before filtering the non-aqueous liquid. [Effects of the Invention]

[0022] There are many potential advantages associated with the present invention. For example, the method described herein can provide a non-aqueous liquid, such as biodiesel, having very low levels of sterol glucosides and / or saturated monoglycerides. The level of sterol glucosides and / or saturated monoglycerides in the filtered non-aqueous liquid may be less than about 10 ppm, e.g., less than about 9 ppm, e.g., less than about 8 ppm, e.g., less than about 7 ppm, e.g., less than about 6 ppm, less than 5 ppm, or less than 4 ppm. The level of sterol glucosides and / or saturated monoglycerides in the filtered non-aqueous liquid may be at least 1 ppm.

[0023] Other advantages provided by the present invention include the possibility that filtration may be performed in a shortened time, or that the contact time between the filter aid and the non-aqueous liquid may be reduced. The temperature during filtration according to the present invention may be close to room temperature, for example, in the range of about 20°C to about 25°C. For example, the temperature range may be about 10°C to about 30°C, for example, about 12°C to about 25°C, for example, about 18°C ​​to about 24°C. The method according to the present invention generally does not require extensive heating and / or cooling, making it a more economical and easier method to implement.

[0024] Any feature in one aspect of the present invention can be applied in any suitable combination to one or more other aspects of the present invention. In particular, aspects of products, apparatuses or articles can be applied to aspects of methods and uses, and vice versa.

[0025] This and other embodiments of the present invention will be described in more detail with reference to the accompanying drawings illustrating embodiments of the present invention. [Brief explanation of the drawing]

[0026] [Figure 1] This shows a typical process flow for filtering non-aqueous liquids, such as biodiesel (or crude FAAE). [Modes for carrying out the invention]

[0027] The present invention will be described in more detail below with reference to the accompanying drawings showing current preferred embodiments of the invention. However, the present invention can be embodied in many different forms and should not be construed as being limited to the embodiments described herein; rather, these embodiments are provided for completeness and comprehensiveness and will adequately convey the scope of the invention to those skilled in the art. Throughout, the same reference numerals in the drawings represent similar elements.

[0028] Where used herein, the terms “comprises,” “comprising,” or any other variation thereof are intended to extend to non-exclusive inclusion, such that a process, method, configuration, article, or apparatus containing a list of elements may include other elements not explicitly listed or specific to such process, method, configuration, article, or apparatus, rather than containing only those elements. The term “exemplary” is used here in the sense of “example” rather than “ideal.”

[0029] When used here, the singular forms ("a," "an," and "the") include plural references unless otherwise indicated in the context. The terms "approximately" and "about" mean approximately the same as the number or value being referenced. When used here, the terms "approximately" and "about" can be understood to encompass ±10% of a particular quantity or value.

[0030] <Non-aqueous liquid> Non-aqueous liquids can be selected from biodiesel. Non-aqueous liquids may consist of biodiesel, may essentially consist of biodiesel, or may contain biodiesel. Biodiesel may be mixed with non-biodiesel, where non-biodiesel means ordinary diesel, general diesel, or petroleum-based diesel. Non-aqueous liquids may include liquids containing about 25% by weight or less of water. Some non-aqueous liquids, for example, biodiesel distillation bottoms, may contain water in the ppm range (e.g., 10 ppm to 10,000 ppm). Some liquids may be washed with water and contain several wt% of water, for example, about 1% to about 5% by weight or about 2% by weight or less, about 3% by weight, or about 4% by weight or less of water.

[0031] The term biodiesel is well understood by those skilled in the art. At least in the United States, biodiesel must meet the ASTM definition of biodiesel itself, such as the specifications for legal diesel vehicle fuels (ASTM D975) and ASTM D6751. ASTM D6751 generally corresponds to the European standard EN 14214. The technical definition of biodiesel is given below.

[0032] Biodiesel is a fuel that consists of monoalkyl esters of long-chain fatty acids derived from vegetable oils or animal fats, called (n-)B100, and meets the requirements of ASTM D6751.

[0033] A biodiesel mixture is a mixture of biodiesel fuel and petroleum-based diesel fuel that meets ASTM D6751, called (n-) BXX, where XX represents the volume percentage of biodiesel fuel in the mixture.

[0034] Biodiesel is produced by a chemical process called transesterification, which separates glycerin from fats and vegetable oils. This process yields methyl ester and glycerin. The methyl ester is used in the production of biodiesel, while the glycerin can be used in various other products, including soap. In relation to the background of the present invention, the discussion presented here provides details regarding the preparation of biodiesel applicable to the present invention.

[0035] The methods for filtering non-aqueous liquids described here focus on biodiesel, but these methods are also suitable for filtering other non-aqueous liquids.

[0036] <Filtering aid materials> In various embodiments of the present invention, the filter aid material may be composed of or essentially composed of one or more of the following: biosource silica, volcanic glass, silicates, diatomaceous earth, perlite, cellulose, and silica gel.

[0037] In some embodiments, the filter aid material can be selected from perlite. The perlite may be expanded perlite or non-expanded perlite. In such cases, the filter aid material may contain perlite, be composed of perlite, or be essentially composed of perlite.

[0038] The filter aid material may be in the form of a composite material or a non-composite material. The filter aid material may include a mixture of materials. For example, the filter aid material may contain a composite material that contains diatomaceous earth and silica gel, is composed of diatomaceous earth and silica gel, or can be essentially composed of diatomaceous earth and silica gel, is composed of such composite material, or can be essentially composed of such composite material. The diatomaceous earth may be coated with silica gel. Further materials may or may not be present in the filter aid material, and if further materials are present, these materials are binder materials that bind the filter aid materials together. The filter aid material may contain adsorbent components and filtration components. If a binder is present, the binder may be a different material from the adsorbent components and filtration components and has the function of binding them together.

[0039] The term "biogenic silica" used here refers to silica produced or provided by living organisms. One example of bioogenic silica is diatomaceous earth (DE). Diatomaceous earth (DE) is formed from diatomaceous earth. Diatomaceous earth is a brittle, light-colored sedimentary rock composed mainly of the siliceous skeletons of diatoms. When diatomaceous earth is crushed into a powder, it is usually called diatomaceous earth.

[0040] Diatomite is a sediment rich in biosource silica in the form of diatom siliceous husks (i.e., shells or skeletons). Diatoms are a diverse array of microscopic single-celled algae belonging to the class Diatophytes, possessing diverse and complex husk structures containing either a magnificent siliceous skeleton or, in living diatoms, two shells that fit together tightly like a pillbox. Because diatomite can form from the remains of aquatic diatoms, diatomite sediments can be found near current or past bodies of water. These sediments are generally divided into two categories based on their source: freshwater and saltwater. Freshwater diatomite is generally extracted from dry lakebeds and can be characterized by a low crystalline silica content and a high iron content. In contrast, saltwater diatomite is generally extracted from marine areas and can be characterized by a high crystalline silica content and a low iron content. The morphology of diatom husks can vary greatly among species and forms the basis for taxonomic classification; at least 2000 different species are known. The surface of each shell is demarcated by a series of openings containing the complex microstructure of the shell, and each shell has a design unique to its individual species. Typical shell sizes can range from approximately 0.75 μm to approximately 1000 μm. Shell sizes may also range from approximately 10 μm to approximately 150 μm. Shells in this size range, when preserved under conditions that maintain chemical equilibrium, can be durable enough to retain most of their porous and complex structure substantially intact over long geological periods.

[0041] In use in this invention, diatomaceous rock or diatomaceous earth may be unfired or fired. Optionally, the diatomaceous rock or diatomaceous earth may be fired. If fired, the diatomaceous earth may be flux-fired or not flux-fired.

[0042] The firing can be carried out according to any suitable process currently known to those skilled in the art or hereafter discovered. In some embodiments, the firing is carried out at a temperature lower than the melting point of the filter aid material. In some embodiments, the firing is carried out at a temperature in the range of about 600°C to about 1100°C. In some embodiments, the firing temperature is in the range of about 600°C to about 700°C. In some embodiments, the firing temperature is in the range of about 700°C to about 800°C. In some embodiments, the firing temperature is in the range of about 800°C to about 900°C. In some embodiments, the firing temperature is selected from the group consisting of about 600°C, about 700°C, about 800°C, about 900°C, about 1000°C, and about 1100°C.

[0043] Flux firing involves performing at least one firing in the presence of at least one flux. Flux firing can be carried out according to any suitable process currently known or hereafter discovered to those skilled in the art. In some embodiments, the at least one flux is any material currently known or hereafter discovered to those skilled in the art that can act as a flux. In some embodiments, the at least one flux is a salt containing at least one alkali metal. In some embodiments, the at least one flux is selected from the group consisting of carbonates, silicates, chlorides and hydroxide salts. In other embodiments, the at least one flux is selected from the group consisting of sodium, potassium, rubidium and cesium salts. In yet another embodiment, the at least one flux is selected from the group consisting of sodium, potassium, rubidium and cesium carbonate salts.

[0044] Other sources of bio-based silica include plants, animals, and microorganisms, which can provide rich sources of silica with unique properties. For example, rice husks contain enough silica to be commercially ashed to obtain siliceous residue commonly known as "rice husk ash." Furthermore, certain types of sponges are also rich sources of silica, and their residue is found in geological sediments as needle-like spicules.

[0045] The term "volcanic glass" as used here refers to glass formed by the rapid cooling of siliceous magma or lava. Several types of volcanic glass are known, including, for example, perlite, pumice, pumice powder, obsidian, and pitchstone. Volcanic glass such as perlite and pumice is found in large quantities in sediments and is widely used commercially. Volcanic ash, often called "tuff" in its solidified state, contains small particles or fragments that can become glassy. The term "volcanic glass" as used here further encompasses volcanic ash.

[0046] Volcanic glass is chemically equivalent to rhyolite. Volcanic glass that is chemically equivalent to trachyte, dacite, andesite, ratite, and basalt is also known, but may be less common. The term "obsidian" generally applies to many silica-rich volcanic glasses. Obsidian glass is classified into subcategories based on its silica content, with rhyolitic obsidian (typically containing about 73% by weight of SiO2) being the most common.

[0047] Perlite is a hydrated volcanic glass that may contain, for example, approximately 72% to 75% by weight of SiO2, approximately 12% to 14% by weight of Al2O3, approximately 0.5% to 2% by weight of Fe2O3, approximately 3% to 5% by weight of Na2O, approximately 4% to 5% by weight of K2O, approximately 0.4% to 1.5% by weight of CaO, and small amounts of other metallic elements.

[0048] Perlite is distinguished from other volcanic glasses by its high chemically bound water content (e.g., about 2% to 5% by weight) and the presence of characteristic concentric or arched onion-shell-like (i.e., perlite) fracturing, which gives it a glassy, ​​pearly luster. Perlite products can be prepared by grinding and thermal expansion and may have unique physical properties such as high porosity, low bulk density, and chemical inertness. As used herein, "perlite" also includes expanded perlite. Perlite may be non-expanded perlite or expanded perlite, or may contain both non-expanded and expanded perlite.

[0049] The perlite used in this invention can be obtained from perlite raw materials, such as perlite ore.

[0050] Suitable process conditions for preparing expanded perlite are disclosed in U.S. Patent Application Publication No. 2006 / 0075930, the entirety of which is incorporated herein by reference. Generally, expanded perlite used in the present invention can be prepared by methods including crushing, grinding, pulverization, screening, and thermal expansion. For example, perlite ore is crushed and ground to separate it into a predetermined particle size range. The separated material can then be heated in air, typically at temperatures between 870°C and 1100°C. Expanded perlite can be prepared using conventional crushing, grinding, and pulverization techniques and separated to meet particle size requirements using conventional separation techniques.

[0051] Expanded perlite can be classified, for example, to provide a desired particle size distribution. For example, expanded perlite (crushed or uncrushed) can be classified by an air classifier, such as a cyclone separator, to remove particles of a certain diameter. For example, before using expanded perlite for filtration, screening can be used to determine the particle size distribution and any fine particles to be removed. Screening refers to separating a particulate material into multiple particle size fractions using one or more sieves of a specific mesh size. Thus, the particle size distribution of a given material can be expressed as the (weight) percentage of particles in the material that are larger or smaller than the mesh size. Expanded perlite may have the particle sizes mentioned herein. For example, expanded perlite may have a median particle size (d) between approximately 30 μm and approximately 50 μm. 50 ) may have.

[0052] A method for preparing perlite for use as a filter aid material may involve dehydrating a glassy mineral, such as perlite raw material.

[0053] Dehydration can be achieved, for example, by heating the perlite raw material and / or by exposing the perlite raw material to a reduced-pressure environment to decrease its moisture content. Suitable process conditions for preparing dehydrated expanded perlite are disclosed in International Publication 2019 / 046499 A1, the entire contents of which are incorporated herein by reference.

[0054] "Cellulose is one of the most abundant biomaterials on Earth. It is generally synthesized by plants, but is also produced by some bacteria. Like starch, cellulose is a homopolymer of glucose, but unlike starch, the glucose monomers are linked by β-1,4 bonds. Cellulose is a strong, fibrous, water-insoluble polysaccharide that plays an essential role in maintaining the structural stability of plant cell walls. Cellulose chains are arranged in microfibrils or bundles of polysaccharides, and microfibrils or bundles of polysaccharides are arranged in fibrils (bundles of microfibrils), in sequence forming the plant cell wall. This arrangement not only helps stabilize plant structures but also suggests that cellulose is a biomaterial with high strength and other excellent mechanical properties." Torok, Bela, and Timothy Dransfield, "Green Chemistry: An Inclusive Approach," Elsevier Press, 2018.

[0055] Cellulose is a very widely used medium manufactured by dispersing fibers in a suspension in water. This suspension is impregnated into a mat structure, compressed, and dried. Different porosities can be achieved by using different processes. The size of the fibers is important. Cellulose fibers are relatively coarse, while glass fibers are finer. Cellulose-based paper is widely used in industrial liquid filtration applications due to its low holding power, low cost, and good mechanical properties. Glass is generally used for experimental purposes.

[0056] Both glass and cellulose paper can be impregnated with adhesives such as melamine, resin, and neoprene to increase their strength and modify their filtration properties. Silicone is also used to provide water repellency for coalescer and separation applications. A very common end use for filter paper is pleated cartridges used in automotive and industrial applications, with a micron range of 0.5 μm to 500 μm. Filter paper is also used in plate-frame presses and pressure leaf presses. Paper is usually supported by punched wire mesh, wire mesh, or synthetic fiber cloth due to its fragility. "Solid-Liquid Separation" by Svarovski and Ladislav, Butterworth-Heinemann, 2000.

[0057] Filtration aid materials may contain, be composed of, or essentially consist of composite filtration aid materials. Therefore, filtration aid materials are sometimes referred to here as composite filtration aid materials. As used herein, the term “composite filtration aid” may refer to materials having a substrate, such as a silicate substrate, and materials precipitated on it. For example, composite filtration aid materials may contain, be composed of, or essentially consist of composites of silica, such as diatomaceous earth and silica gel. Silica, such as silica gel, may be coated on or precipitated on the surface of a silicate (e.g., diatomaceous earth) substrate. Silica, such as silica gel, may be coated on or precipitated on part, substantially, or entirely on the surface of a silicate (e.g., diatomaceous earth) substrate. The silicate (e.g., diatomaceous earth) substrate can act as a filtering component, while the precipitated silica (e.g., silica gel) can act as an adsorbent component. A composite filtration aid may have different properties from either the constituent substrate or materials precipitated on it alone.

[0058] To prepare a composite filter aid material suitable for use in the present invention, a silicate substrate, such as diatomaceous rock, bio-based silica, or volcanic glass (e.g., perlite), can be mixed with water to form a suspension. The substrate may be a commercially available diatomaceous rock or perlite filter component. Suitable commercially available diatomaceous rocks include, for example, Celite Standard Super Cel® from Imerys. The substrate may also be a commercially available filter component selected from the group including Celite 3Z®, Celite 577®, Celite 289®, Celite 512®, Celite 535®, Celite 545®, Celite Filter-Cel®, and Celite Hyflo Super-Cel®, all from Imerys. The substrate may also be a commercially available component selected from the group generally called Harborlite®. A specific example is Harborlite® 900, also commercially available from Imerys.

[0059] Precipitated silica may include precipitated silica gel that settles on a silicate substrate. Precipitated silica may also be amorphous silica.

[0060] Next, a sodium silicate solution may be added to the substrate suspension, thereby increasing the pH. The weight ratio of sodium silicate to the substrate can be, for example, about 1:3, but any suitable ratio can be used. The sodium silicate can include any of several compounds containing sodium oxide (Na2O) and silica (SiO2). Such combinations include, for example, orthosilicate sodium (Na4SiO4), metasilicate sodium (Na2SiO3), and disilicate sodium (Na2Si2O5). In some embodiments, the sodium silicate is diatomaceous rock-based sodium silicate. Sodium silicate with an SiO2 / Na2O ratio of about 3.2:1 and a concentration of 20% can be purchased, for example, from Imerys. Sodium silicate with an SiO2 / Na2O ratio of about 3:1 and a concentration of 34.6% can be purchased, for example, from PQ Corporation.

[0061] Then, a sufficient amount of acid or a salt thereof can be added to the slurry to increase its acidity (i.e., decrease its pH) until the pH range is suitable for the silica to precipitate onto the surface of the substrate. Within the scope of the know-how of those skilled in the art, any suitable acid can be selected, and the acid may include one or more of sulfuric acid, phosphoric acid, hydrochloric acid, nitric acid, and / or acetic acid. The precipitated silicate can form a coating (e.g., a layer) on the surface of the substrate.

[0062] When lowering the pH, the slurry may be stirred periodically. According to some embodiments, stirring may continue until silica gelation occurs, thereby forming a coating on the substrate. According to some embodiments, stirring can be carried out for about 25 to 60 minutes, depending on the acidity of the solution and the concentration of sodium silicate in the slurry. The slurry can then be filtered, and water can be added to the suspension to facilitate filtration. The resulting cake may be washed with water. The washed cake can then be dried until any excess fluid in the cake evaporates. For example, the cake can be dried at a temperature in the range of about 110°C to about 200°C, and the resulting cake may contain a silicate filter component having a precipitated silica coating, such as diatomaceous rock (or diatomaceous earth).

[0063] Precipitated silica can contain co-gels. For example, magnesium sulfate, sodium aluminate, or both can be added to a sodium silicate solution that forms precipitated silica or precipitated silica gel. The addition of sulfates or aluminates may form a silicate structure together with the precipitated silicate. If the precipitated silicate is a gel such as silica gel, the addition of sulfates or sodium aluminate may form a co-gel.

[0064] The filter aid materials disclosed herein have particle size. Particle size can be measured by any suitable measuring technique currently known to those skilled in the art or hereafter discovered. In one typical method, particle size properties such as particle size and particle size distribution ("psd") are measured using a Leeds and Northrup Microtrac X100 laser particle size analyzer (Leeds and Northrup, Pennsylvania, USA). The size of a given particle is expressed as the diameter of a sphere with an equivalent diameter that settles in a suspension, also known as equivalent sphere diameter or "esd". Median particle size, or d 50 The value is that 50% by weight of the particles is its d 50 This is a value that has an ESD smaller than the given value. 10 The value is 10% by weight of the particles. 10 This is a value that has an ESD smaller than the given value. 90 The value is that 90% by weight of the particles is its d 90 This is a value with an ESD smaller than the given value.

[0065] The filter aid material has a median particle size (d) in the range of approximately 1 μm to approximately 300 μm, for example, approximately 40 μm to approximately 300 μm, approximately 40 μm to approximately 250 μm, approximately 100 μm to approximately 250 μm, approximately 5 μm to approximately 150 μm, approximately 40 μm to approximately 140 μm, approximately 60 μm to approximately 120 μm, approximately 20 μm to approximately 50 μm, approximately 30 μm to approximately 50 μm, approximately 30 μm to approximately 60 μm, approximately 60 μm to approximately 90 μm, approximately 90 μm to approximately 120 μm, approximately 120 μm to approximately 150 μm, approximately 1 μm to approximately 40 μm, approximately 10 μm to approximately 40 μm, approximately 10 μm to approximately 30 μm, or approximately 15 μm to approximately 25 μm. 50 ) may have.

[0066] The filter aid material may have a d value in the range of about 50 μm or more and about 700 μm or less, for example, about 300 μm or more and about 700 μm or less, about 300 μm or more and about 500 μm or less, about 100 μm or more and about 300 μm or less, about 200 μm or more and about 400 μm or less, about 50 μm or more and about 300 μm or less, about 100 μm or more and about 200 μm or less, about 200 μm or more and about 300 μm or less, about 50 μm or more and about 100 μm or less, about 60 μm or more and about 140 μm or less, about 70 μm or more and about 120 μm or less, or about 80 μm or more and about 110 μm or less. 90 It may have a value.

[0067] The filter aid material may have a d value in the range of about 1 μm or more and about 30 μm or less, for example, about 1 μm or more and about 10 μm or less, about 10 μm or more and about 20 μm or less, about 20 μm or more and about 30 μm or less, about 5 μm or more and about 15 μm or less, about 15 μm or more and about 25 μm or less, about 20 μm or more and about 25 μm or less, about 2 μm or more and about 20 μm or less, about 3 μm or more and about 15 μm or less, about 4 μm or more and about 12 μm or less, about 5 μm or more and about 10 μm or less, about 1 μm or more and about 5 μm or less, or about 1 μm or more and about 3 μm or less. 10 It may have a value.

[0068] The d values considered individually or in any combination and given 10 , d 50 and d 90 are applicable to each of the filter aid materials described herein. Each specific value or range of values can be applied to any of biogenic silica, volcanic glass, silicate, diatomaceous earth, perlite (including expanded perlite or unexpanded perlite), cellulose, and silica gel.

[0069] The filter aid material may have permeability ranging from approximately 50 millidarcy to approximately 5000 millidarcy ("md"). For example, the filter aid material may have permeability ranging from approximately 50md to approximately 2000md, approximately 50md to approximately 1000md, approximately 50md to approximately 500md, approximately 50md to approximately 300md, approximately 50md to approximately 200md, approximately 50md to approximately 100md, approximately 100md to approximately 400md, approximately 100md to approximately 300md, approximately 100md to approximately 200md, approximately 200md to approximately 300md, approximately 100md to approximately 4000md, approximately 100md to approximately 3000md, and approximately 500md to approximately 30 The permeability may be in the range of 00 md or less, approximately 500 md to approximately 1500 md, approximately 1500 md to approximately 3000 md, approximately 200 md to approximately 2000 md, approximately 200 md to approximately 1000 md, approximately 200 md to approximately 500 md, approximately 500 md to approximately 1000 md, approximately 1000 md to approximately 1500 md, approximately 1500 md to approximately 2000 md, approximately 2000 md to approximately 2500 md, approximately 2500 md to approximately 3000 md, or approximately 1000 md to approximately 2000 md. Permeability can be measured by any suitable measuring technique currently known to those skilled in the art or to be discovered in the future. Permeability is generally measured in darcy units or darcy, per 1 cm of a 1 cm high porous bed. 2 In the cross-section, a fluid (e.g., water) with a viscosity of 1 mPa*s at a pressure difference of 1 atmosphere at 20°C will have a viscosity of 1 cm³. 3It is determined by the permeability when flowing at a flow rate of 1 / second. The principle of measuring permeability has been derived in advance for porous media from Darcy's Law (see, for example, "The Equation of Motion of a Homogeneous Fluid: Deivations of Darcy's Law" in J. Bear's "Dynamics of Fluids in Porous Media 161-177" (2nd edition 1988)). A range of apparatuses and methods exist that can correlate with permeability. In one typical method useful for measuring permeability, a specially constructed apparatus is designed to form a filter cake on a partition from a suspension of the filter medium in water; the measured thickness of the filter cake, having a known cross-sectional area, is determined by the time required for a given amount of water to flow through it. Each specific value or range of values ​​can be applied to any of the following: biosource silica, volcanic glass, silicates, diatomaceous earth, perlite (including expanded or unexpanded perlite), cellulose, and silica gel.

[0070] The term "surface area" used herein refers to the BET surface area. The BET surface area, as used herein, refers to the technique for calculating the specific surface area of ​​a physical absorbent molecule according to the theory of Brunauer, Emmett, and Teller ("BET"). The BET surface area can be measured using the Gemini III 2375 surface area analyzer, which uses nitrogen as the adsorbent gas, or the ASAP® 2460 surface area and porosimetry analyzer, available from Micromeritics Instrument Corporation (Norcross, Georgia, USA). The filter aid material is approximately 0.5 m². 2 / g, approx. 1m 2 / g, approx. 5m 2 / g, approx. 10m 2 / g or approximately 25mg 2 / g or more 440m 2 It may have a BET surface area in the range of less than or equal to / g. For example, the filter aid material may have a BET surface area of ​​approximately 50m². 2 / g or more about 300m 2 / g or less, about 50m 2 / g or more about 200m 2 / g or less, about 50m2 / g or more about 150m 2 / g or less, about 100m 2 / g or more about 200m 2 / g or less, or approximately 100m 2 / g or more about 150m 2 It may have a BET surface area in the range of less than or equal to / g. Each specific value or range of values ​​can be applied to any of the following: biosource silica, volcanic glass, silicates, diatomaceous earth, perlite (including expanded or unexpanded perlite), cellulose, or silica gel.

[0071] According to some embodiments, the filter aid material is approximately 5 lbs / ft 3 Or approximately 10 lbs / ft 3 Approximately 40 lbs / ft 3 The wet density may be within the following range. For example, the filter aid material may have a wet density of approximately 5 lbs / ft. 3 Or approximately 10 lbs / ft 3 Approximately 20 lbs / ft 3 Below, about 5lbs / ft 3 Or approximately 10 lbs / ft 3 Approximately 15 lbs / ft 3 Below, about 20lbs / ft 3 More than about 30lbs / ft 3 Below, about 15lbs / ft 3 More than about 25lbs / ft 3 Below, about 25lbs / ft 3 More than about 35lbs / ft 3 Below, about 15lbs / ft 3 Approximately 20 lbs / ft 3 Below, about 20lbs / ft 3 More than about 25lbs / ft 3 Below, or approximately 25 lbs / ft 3 More than about 30lbs / ft 3 The following ranges of wet densities may be observed. Each specific value or range of values ​​may apply to any of the following: biosource silica, volcanic glass, silicates, diatomaceous earth, perlite (including expanded or unexpanded perlite), cellulose, and silica gel.

[0072] "Wet density" is an indicator of the porosity of a material. For example, wet density reflects the void volume available for trapping particulate matter in a filtration process, and therefore can be used to determine filtration efficiency. Wet density further indicates the percentage porosity of the material and can be expressed by the following formula: Porosity = 100 * [1 - (Wet Density / True Density)]

[0073] Therefore, filter aid materials or, for example, filter components with a lower wet density will result in a product with a greater porosity, and thus, if the true density is kept relatively constant, will likely result in greater filtration efficiency. Assuming that the wet density reflects the porosity volume of the adsorbent component for capturing substances in the filtration process, a lower wet density may indicate that the adsorbent component has a higher porosity volume, thereby enabling it to adsorb more particles and / or components in the fluid.

[0074] In accordance with a typical method, to measure the wet density, a material sample of a known weight between approximately 1.00 g and approximately 2.00 g is placed in a calibrated 15 ml centrifuge tube. Deionized water is then added to bring the volume to approximately 10 ml. The mixture is shaken thoroughly until all of the sample is wet and no powder remains. Additional deionized water is added around the top of the centrifuge tube, and shaking is used to rinse off any mixture adhering to the sides of the tube. The centrifuge tube is then centrifuged at 2500 rpm for 5 minutes using an IEC Centra® MP-4R centrifuge equipped with a Model 221 swinging bucket rotor (International Equipment Company; Needham Heights, Massachusetts, USA). After centrifugation, the centrifuge tube is carefully removed without disturbing the solid. The level (i.e., volume) of the precipitate is measured in cm³. 3 It is expressed as follows. The wet density of the centrifuged powder can be determined by dividing the sample weight by the measured volume.

[0075] <Surface energy> The surface energy of filter aid materials can be measured using known techniques. According to the present invention, surface energy can be measured using an inverse gas chromatography surface energy analyzer (iGC-SEA) supplied by Surface Measurement Systems, Ltd., headquartered in Alperton, London, HA0 4PE, UK. The operation of iGC-SEA is based on the inverse gas chromatography (IGC) methodology and is a gas-phase technique for evaluating the surface and bulk properties of solid materials. Essentially, the measurement is the reverse of a conventional gas chromatography (GC) experiment. A cylindrical column is uniformly packed with the target solid material, typically in powder form for the purposes of the present invention. Next, pulses of a constant gas concentration are injected into the column at a constant carrier gas flow rate, and the time required for the pulse or concentration front to elute from the column is measured by a detector. A series of IGC measurements using various gas-phase probe molecules provide access to a wide range of physicochemical properties of the solid sample. The injected gas molecules pass through the material and adsorb onto the surface with a partition coefficient Ks. Ks = Vn / Ws

[0076] Here, Vn is the total corrected retention volume, which is the volume of carrier gas required to elute the injector through the column, and Ws is the mass of the sample. Vn is a measure of how strongly the probe gas interacts with the solid sample and is considered fundamental data obtained from IGC experiments that can calculate various surface and bulk properties. Regarding the notation γd0.16, γd0.08, and γd0.0016, the number after the gamma (γ) value indicates the surface coverage by gas. Therefore, γd0.16 indicates that 16% (volume) of the surface is covered by gas, γd0.08 indicates that 8% (volume) of the surface is covered by gas, and γd0.0016 indicates that the surface is 0.16 This indicates that (volume)% is covered by gas.

[0077] For example, in order to measure the surface energy using iGC-SEA, the following steps can be performed according to the present invention.

[0078] 1. Measure the BET surface area of ​​the filter aid material sample. The term "surface area" used herein refers to the BET surface area. The term "BET surface area" here refers to the technique for calculating the specific surface area of ​​a physical absorbent molecule according to the theory of Brunauer, Emmett, and Teller ("BET"). The BET surface area can be measured using a Gemini III 2375 surface area analyzer that uses nitrogen as the adsorbent gas, or an ASAP® 2460 surface area and porosimetry analyzer available from Micromeritics Instrument Corporation (Norcross, Georgia, USA).

[0079] 2. A certain amount of filter aid material is packed into a cylindrical glass column. The amount of material packed into the column is approximately 7 mm in height for a column with an inner diameter of 2 mm, or approximately 0.5 m 2 It should have a BET surface area. Surface area measurement is used when the level of material in the column is high.

[0080] 3. Load the column filled with the filter aid material into the iGC-SEA.

[0081] 4. Surface energy was measured at 50°C.

[0082] 5. The dispersed surface energy (γd) is measured using at least three of the following alkanes: heptane alkanes, octane alkanes, nonane alkanes, decane alkanes, and dodecane alkanes. The alkane that provides the highest surface coverage of 0.16 is preferred. The elution rate should be low (e.g., about 7 cm). 3 A elution rate of at least 0.2 minutes per minute is preferred. Typically, the elution rate needs to be sufficiently low so that the elution time is at least about 0.2 minutes.

[0083] 6. Measure the basic surface energy (γ-) using dichloromethane (CH2Cl2). The elution rate should be low (e.g., about 7 cm). 3A elution rate of at least 0.2 minutes per minute is preferred. Typically, the elution rate needs to be sufficiently low so that the elution time is at least about 0.2 minutes.

[0084] 7. Measure the acid-type surface energy (γ+) using ethyl acetate (CH3COOC2H5). A higher elution rate is used for measuring γ+ than for γ-. For example, 20 cm 3 / min 20cm 3 Elution rates greater than 1 / minute are appropriate, and longer experimental times (e.g., up to approximately 500 minutes) are recommended to reduce surface coverage (e.g., less than 0.05). Elution peaks can be identified from the raw data chromatogram for at least one data point with a surface coverage of 0.01 or less and one data point with a surface coverage between 0.01 and 0.05. Manual peak identification can be used in data analysis software.

[0085] 8. Use SEA data analysis software to calculate various surface energies γd(0.16), γd(0.08), γd(0.0016), γ+, and γ-.

[0086] (filtration method) Non-aqueous liquids (e.g., biodiesel) can be filtered using established techniques and / or apparatus. For example, a filter aid material can be packed into a column, and the non-aqueous liquid can be filtered with or without additional pressure. Preferably, the non-aqueous liquid should be in contact with the filter aid material for at least about 10 minutes. The non-aqueous liquid can be in contact with the filter aid material for up to about 30 minutes. Depending on the properties of the filter aid material used, and the desired level of sterol glucoside and / or saturated monophosphate, GlyceridesTo achieve and / or to achieve the desired low-temperature immersion time in accordance with ASTM D7501, the contact time may be varied. The temperature at which filtration is performed can also be controlled and / or varied. For example, the temperature can be maintained in a range of about 10°C to about 30°C, e.g., about 12°C to about 25°C, e.g., about 18°C ​​to about 24°C, or about 20°C to about 25°C. This time (range) and temperature (range) may be referred to here as “processing time” and “processing temperature”.

[0087] Figure 1 shows a typical process flow toward a non-aqueous liquid (e.g., biodiesel or FAAE). Figure 1 is a schematic diagram of biodiesel purification by a filtration system. The filtration system (10) includes an adsorption column (12) having an adsorbent material (14). The adsorbent material (14) includes a filter aid for purifying biodiesel (16). The biodiesel (16) may be crude biodiesel or pre-filtered biodiesel. Although Figure 1 shows only a single adsorption column (12), it is understood that two or more adsorption columns may be arranged in series and / or parallel to increase the filtration rate of the filtration system (10) and / or improve the purification of filtered biodiesel. The crude biodiesel (16) may contain fatty acid alkyl esters (FAAEs) or crude oil feed, which is brought into contact with a sufficient amount of adsorbent material (14) to remove impurities such as sterol glycosides and / or saturated monoglycerides. Other impurities may include one or more of the following: soap, phosphorus-containing compounds, catalysts, metals, free glycerin, chlorophyll, free fatty acids, and other impurities that reduce the stability of biodiesel. A suitable adsorbent material (14) includes the filter aid materials described herein (e.g., perlite), which may include further filter aid materials. After passing through the adsorbent material (14), the biodiesel is considered filtered biodiesel (18).

[0088] The purified biodiesel (18) is discharged from the adsorption column (12) and optionally passed through an evaporator (20). The evaporator (20) can be used to recover alcohol components of the purified biodiesel (18), such as methanol. The evaporator (20) may be a flash evaporator. After passing through the evaporator (20), the biodiesel can undergo further processing to produce a biodiesel product (22).

[0089] As biodiesel (16) passes through the adsorbent material (14), impurities accumulate on the adsorbent material (14), reducing the flow rate and filtration efficiency of the adsorbent material (14). This combined layer of impurities and filter aids is sometimes called a "filtration cake." As more particles and / or impurities accumulate on the filtration cake, the filtration cake can become saturated with debris to the point where the fluid can no longer pass through at an acceptable rate. To mitigate this problem, additional filter aids can be introduced by a "body feed." A body feed is the process of introducing additional filter aids into the fluid to be filtered before it reaches the filtration cake, for example, before the biodiesel (16) comes into contact with the adsorbent material (14). The filter aids follow the path of the unfiltered fluid, and upon reaching the adsorbent material (14), the added filter aids either bind to the filtration cake or settle. These additional layers of filter aid material expand and thicken the filter cake, increasing its volume and trapping further debris and impurities. Body feed also helps the filter aid material maintain an open structure within the filter cake, which can help maintain the permeability and flow rate of the filter cake.

[0090] Filtration aid materials can be used in various filtration processes and configurations. Filtration elements can be used to support the filtration aid material. Filtration elements may contain voids through which fluid flows. Filtration aid materials may be applied to filtration partitions to protect them and / or to improve the clarity of the liquid being filtered in the filtration process. Filtration aid materials may be added directly to the fluid being filtered (e.g., non-aqueous fluids such as biodiesel) to increase flow rate and / or extend the filtration cycle. Filtration aid materials can be used in the filtration process as a pre-coating layer on the filtration element in a body feed to improve the lifespan of the filtration cake and / or maintain the flow characteristics through the filter, or in a combination of pre-coating and body feed.

[0091] Filter aid materials can also be used in various filtration methods. A filtration method may include pre-coating at least one filter element with a filter aid material and bringing at least one liquid to be filtered into contact with at least one coated filter element. In such embodiments, contact may include passing the liquid through the filter element. In some embodiments, a filtration method includes suspending the filter aid material in the liquid to be filtered and then separating the filter aid material from the filtered liquid.

[0092] After filtration, the amount of sterol glucosides and / or saturated monoglycerides in the non-aqueous liquid (e.g., biodiesel) may be less than about 10 ppm, e.g., less than about 9 ppm, e.g., less than about 8 ppm, e.g., less than about 7 ppm, e.g., less than about 6 ppm, less than 5 ppm, or less than 4 ppm. The level of sterol glucosides and / or saturated monoglycerides in the filtered non-aqueous liquid may be at least 1 ppm.

[0093] The levels of sterol glucosides and / or saturated monoglycerides in non-aqueous liquids can be measured by ASTM D6584. [Examples]

[0094] The present invention will be described merely as an example and without limitation with reference to the following examples. For example portions relating to the same features, samples, materials, filter aid materials, or adsorbents may be referenced.

[0095] <Test Method and Samples> Table 1 shows details of the filter aid materials used in the tests. All materials used were commercially available.

[0096] Filtration of non-aqueous liquids and subsequent low-temperature immersion testing (ASTM D75) 01 Details regarding this are provided below.

[0097] The dosage (by weight) is relative to the total weight of the non-aqueous liquid and the added filter aid material.

[0098] In the following examples, the filter aid material and biodiesel were mixed at specific "processing times" and "processing temperatures." In Table 5, the time required to filter the mixture is indicated in the "400 ml filtration time after cooling" column.

[0099] <Filtration of non-aqueous liquids> In accordance with the present invention, a non-aqueous liquid was filtered using a filter aid material. The sample was filtered according to the following procedure.

[0100] A flask containing 1,400 ml of non-aqueous liquid (biodiesel) was placed in a water storage area maintained at a target temperature, and left to stand to allow the non-aqueous liquid in the flask to reach the same temperature as the water. A weight was used to stabilize the flask containing the non-aqueous liquid.

[0101] 2. A stirrer was placed in the flask, and the non-aqueous liquid was stirred at 300 rpm using a PTFE impeller. The temperature of the non-aqueous liquid was recorded with a thermometer to confirm that it reached the desired temperature ("filtration temperature").

[0102] 3. Once the non-aqueous liquid reached the desired temperature, the filter aid material was added, and the mixture was stirred for approximately 10 minutes.

[0103] A 4.90mm Whatman #4 paper was placed on the surface of a 600ml Buchner filter.

[0104] 5. A vacuum was generated, and the mixture of non-aqueous liquid and filter aid material slurry was filtered.

[0105] 6. The duration of filtration was recorded ("filtration time for 400 ml after cooling").

[0106] 7,300 ml of the filtrate was set aside for the cold immersion method (ASTM D7501), and the remaining filtrate was kept for other tests, including ICP.

[0107] <Low temperature immersion method: ASTM D7501> After filtration, the obtained non-aqueous liquid was subjected to a low-temperature immersion test according to ASTM D7501. The sample was subjected to the low-temperature immersion method according to ASTM D7501 as described below.

[0108] 1. Before the low-temperature immersion test, the "thermal history" of the sample was restored. The sample was heated at 40°C for 3 hours and then left to stand at room temperature (20°C) for another 24 hours.

[0109] 2,300 mL of the sample was poured into a 500 mL Erlenmeyer flask and placed in a chiller reservoir at 20°C with a donut-shaped weight. The flask was covered with Parafilm® to prevent oxidation of the oil.

[0110] 3. The filtrate was left in a cooling tank for 16 hours.

[0111] 4. The temperature of the cooling tank was set to 25°C, and the filtrate was allowed to stand for another 2 hours.

[0112] 5. The glass fiber filter was assembled by placing a metal partition ring in the lower half of the filter assembly, and the top surface was flushed. A 0.7 μm thick glass fiber filter was inserted, a funnel was placed on top, and it was secured with clamps.

[0113] 6. Gently swirl the flask to dislodge any particles that may have adhered to the sides. Avoid vigorous shaking to prevent any existing solids from redissolving.

[0114] 7. A vacuum (70-85 kPa (21-25 in-Hg)) was applied and the liquid was injected. The duration of filtration ("low immersion time") was recorded and completed when the surface of the paper was dry. For the test to be considered "pass," the time should be less than 360 seconds. High-grade biodiesel, referred to as 1-B, corresponds to a filtration time of 200 seconds or less and a monoglyceride concentration of 0.4% by weight or less. [Table 1]

[0115] <Example 1> Several adsorbents were tested using the cold immersion method. The biodiesel used in the test was corn-based biodiesel, which we will refer to here as Biodiesel A. The results are shown in Table 2. [Table 2]

[0116] <Example 2> Several adsorbents were tested using the low-temperature immersion method. The biodiesel used in the test was soy-based, and is referred to here as Biodiesel B. The results are shown in Table 3. [Table 3]

[0117] <Example 3> Several adsorbents were tested using the cold immersion method. The biodiesel tested was soy-derived biodiesel, referred to here as Biodiesel C. TSG is the total sterol glucoside present in ppm units and is measured by gas chromatography, ASTM D6584. The results are shown in Table 4. [Table 4]

[0118] <Example 4> Several adsorbents were tested using the cold immersion method. The biodiesel tested was soy methyl ester, referred to here as Biodiesel D. The results are shown in Table 5. The 400 mL filtration time after cooling is the time required to filter the biodiesel before performing the test (cold immersion time) according to ASTM D7501. [Table 5]

[0119] <Example 5> Several adsorbents were tested using the cold immersion method. The results are shown in Table 6. The biodiesel used in the test was soy methyl ester. E This is called [the surface energy]. Table 6 also shows the surface energy results. [Table 6]

[0120] Other embodiments of the present invention will be apparent to those skilled in the art in consideration of the specification and practices of the present invention disclosed herein. The specification and examples are intended to be considered illustrative only, and the true scope and spirit of the invention are shown by the following claims.

Claims

1. The process includes the steps of preparing a non-aqueous liquid and filtering the non-aqueous liquid through a filter aid material, wherein the filter aid material contains cellulose. The dispersion surface energy (γd 0.08) of the aforementioned filter aid material is greater than 32. A method for filtering a non-aqueous liquid, characterized in that the ratio of the basic surface energy to the acidic surface energy (γ- / γ+) of the filter aid material is greater than 1.

2. The method according to claim 1, wherein the filter aid material contains one or more of the following: bio-based silica, volcanic glass, silicates, diatomaceous earth, perlite, and silica gel.

3. The method according to claim 1 or 2, wherein the filtration aid material contains perlite.

4. The method according to claim 3, characterized in that the perlite is expanded perlite.

5. The method according to claim 3, characterized in that the perlite is non-expanding perlite.

6. The method according to any one of claims 1 to 5, wherein the filter aid material is a composite material.

7. The method according to claim 6, wherein the composite material contains diatomaceous earth and silica gel.

8. The method according to claim 3, wherein the perlite is crushed perlite.

9. The median particle size of the cellulose (d ５０ The method according to any one of claims 1 to 8, wherein the thickness is approximately 20 μm or more and approximately 50 μm or less.

10. The median particle size of the cellulose (d ５０ The method according to any one of claims 1 to 8, wherein the thickness is approximately 30 μm or more and approximately 50 μm or less.

11. The wet density of the cellulose is approximately 5 lbs / ft. ３ Approximately 20 lbs / ft ３ The method according to any one of claims 1 to 10, which is as follows:

12. The wet density of the cellulose is approximately 10 lbs / ft. ３ Approximately 20 lbs / ft ３ The method according to any one of claims 1 to 10, which is as follows:

13. The method according to any one of claims 1 to 12, wherein the filter aid material adsorbs sterol glucoside and / or saturated monoglycerides from a non-aqueous liquid.

14. The method according to any one of claims 1 to 13, wherein the non-aqueous liquid contains biodiesel.

15. The method according to claim 14, wherein the biodiesel is based on ASTM D6751.

16. The method according to claim 14 or 15, wherein the non-aqueous liquid further contains petroleum-based diesel fuel.

17. The method according to any one of claims 1 to 16, wherein the non-aqueous liquid is filtered in a temperature range of about 10°C to about 30°C.

18. The method according to any one of claims 1 to 16, wherein the non-aqueous liquid is filtered in a temperature range of about 12°C to about 25°C.

19. The method according to any one of claims 1 to 18, wherein the filter aid material is added to a non-aqueous liquid as a body feed.

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