WO2011113827A1 - Metal carbonate containing catalysts and their use in solid basic catalyst-catalyzed reactions - Google Patents

Abstract

The present invention relates to catalysts comprising a metal component containing at least one metal component selected from Group IA metals of the Periodic Table, Group HA metals of the Periodic Table, and mixtures thereof, and at least one additional component, wherein said metal component comprises at least one oxide and at least one carbonate of the at least one metal, their preparation, and their use. The present invention also relates to methods of preparing such catalysts and the use thereof.

Description

METAL CARBONATE CONTAINING CATALYSTS AND THEIR USE IN SOLID BASIC CATALYST-CATALYZED REACTIONS

FIELD OF THE INVENTION

[0001] The present invention relates to metal carbonate-containing catalysts suitable for use in base catalyzed reactions. More specifically, the present invention relates to catalysts useful in the production of fuels.

BACKGROUND

[0002] In general basic catalysis can be carried out with, for example, gas or liquid bases and solid basic catalysts. In general, solid basic catalysts are preferred because, among other reasons, the catalysts can be recovered from the product mixtures more readily, providing process benefits such as lower catalyst consumption/loss and less waste products. For example, biodiesel can be produced via transesterification of vegetable oils via basic catalysis. Common catalysts used, are liquid catalysts, as for example sodium methoxide or sodium hydroxide. Catalytic transesterification implies contacting a feed of glyceride esters (e.g., vegetable oil, animal fat) with an alcohol or a mixture of alcohols in the presence of a transesterification catalyst. In this process glycerides are converted into their corresponding esters. For biofuel purposes, feeds are generally converted with lower alcohols (i.e. methanol and ethanol) to methyl and ethyl esters, with glycerin as a by-product.

[0003] Homogeneous transesterification reactions, using liquid catalysts for biodiesel production, suffer from corrosiveness of the catalyst, high catalyst material usage and large waste streams, resulting of the washing stages or salt separation. Separation of dissolved catalyst from the biodiesel or glycerin phases are a substantial part of total process costs. The use of solid catalyst systems is needed to reduce the separation issues. Heterogeneous catalyst systems often require highly elevated temperatures, resulting in high (autogenous) pressure operation (with associated safety hazards) and more expensive equipment. At low temperatures, operation has proven to be difficult resulting in lack of activity. In addition, stability and lifetime of heterogeneous catalysts during long term operation is an important factor for industrial scale operation.

[0004] Because of requirements with respect to legally permitted metals and salts in waste water and in addition requirements to activity levels and lifetime, there is a continuous need for solid basic catalysts with improved activity and stability. In the process, a more active catalyst will make it possible to operate under milder process conditions (energy saving) or to increase the life-span of a catalyst (cycle length).

[0005] Industrial application of solid basic catalysts demands that the catalyst has an excellent lifetime. In addition, catalysts should not suffer from deactivation or destabilization by impurities of the feedstocks used or processes exploited. For example, in biodiesel industry water contamination of feeds is an issue, hampering catalyst life of solid basic catalysts, more specifically calcium containing catalysts. In addition, during loading and handling, it is assumed that air, C0₂ or water vapor can be detrimental for solid basic catalysts, drastically decreasing catalyst life times.

[0006] In an effort to satisfy these needs, there has been much work to develop suitable transesterification catalysts. For example, WO06134845 Doshisha (Hidaka J.) teaches solid base catalysts containing calcium oxide for producing biodiesel, and Journal of Molecular Catalysis A: Chemical 276 (2007) 24-33 ( gamcharussriichai) describes calcined dolomite catalyst where "the high activity of the catalyst should be due to the presence of two active CaO sites generated from the precipitated Ca(OH)2 located in the crystalline phase of dolomite and from CaC0₃ remaining after the calcination of the parent dolomite at 600-700°C".

[0007] However, there is still a need in the art for a catalyst that provides both suitable activity and aging characteristics.

SUMMARY OF THE INVENTION

[0008] In one embodiment, the present invention relates to a catalyst comprising a metal component containing at least one metal selected from Group IA metals of the Periodic Table, Group IIA metals of the Periodic Table, and mixtures thereof, and at least one additional component, wherein said metal component comprises at least one oxide and at least one carbonate of the at least one metal.

[0009] In another embodiment, the present invention relates to a process for preparing a catalyst comprising combining at least one metal carbonate selected from carbonates of Group IA, Group IIA, and mixtures thereof and at least one additional component thereby forming a catalyst precursor, shaping said catalyst precursor, and thermally treating said catalyst precursor thereby forming a catalyst comprising a metal component containing at least one metal selected from Group IA metals of the Periodic Table, Group IIA metals of the Periodic Table, and at least one additional component, wherein said metal component comprises at least one oxide and at least one carbonate of the at least one metal.

[0010] In yet another embodiment, the present invention relates to a process for preparing comprising contacting a bio-feedstream with a catalyst comprising a metal component containing at least one metal selected metal from Group IA metals of the Periodic Table, Group IIA metals of the Periodic Table, and mixtures thereof, and at least one additional component, wherein said metal component comprises at least one oxide and at least one carbonate of the at least one metal, thereby producing a fuel product, and optionally contacting said fuel product with a homogenous acidic material. In these embodiments, the bio-feedstreams and process conditions can be selected to produce a variety of products. In some embodiments, the bio-feedstream and process conditions are selected from those effective at producing products suitable for use as fuels. Thus, in some embodiments, the present invention relates to a process effective at producing fuel products.

DETAILED DESCRIPTION OF THE INVENTION

Catalyst

[001 1] As noted above, the catalysts of the present invention comprise a metal component containing at least one metal selected from Group IA metals, Group IIA metals, and mixtures thereof. In preferred embodiments, the at least one, preferably only one, metal is selected from the Group IIA metals of the Periodic Table, most preferably calcium. The at least one metal component is not impregnated onto the at least one additional component, but is present as a separate phase dispersed throughout the additional component. In preferred embodiments, the at least one metal component is homogenously dispersed.

[0012] The at least one metal component comprises at least one, preferably one, oxide and at least one, preferably one, carbonate of the at least one metal. In exemplary embodiments, the catalyst comprises CaO and CaC0₃. The amount of the at least one metal component is in the range of from about 10 wt% to about 95 wt% (expressed as the metal oxide and based on the total weight of the catalyst), preferably in the range of from about 55 wt% to about 90 wt% all based on the total weight of the catalyst. The elemental composition of the catalyst can be determined via AAS or ICP or XRF on the catalyst after calcination in air at 600°C for 1 hour. The amount of the at least one carbonate, as measured with XPS, is in the range of from about 25 wt% to about 50 wt% (expressed as the metal carbonate, based on the total weight of the catalyst), preferably in the range of from about 30 wt% to about 45 wt%. The inventors hereof have discovered that the presence of the carbonate and oxide in the final catalyst provides for a catalyst having leaching, performance, and aging characteristics superior to those currently available. While not wishing to be bound by theory, the inventors hereof believe that the presence of the carbonate in the final catalyst provides leaching and aging protection to the oxide species and also provides performance benefits to the catalyst. It should be noted that the weight percentages described above are measured on a dry basis. By "on a dry basis", it is meant the weight percentages are measured after drying the catalyst at 120°C for 12 hours.

[0013] The catalysts of the present invention also comprise at least one additional component derived or derivable from silica, silica-alumina, alumina, cationic clays or anionic clays, aluminum stearate, graphite, graphene, organic compounds, (poly)silicic acid, sodium silicate, silicon containing components, organic silicon sources, zeolites, or mixtures thereof. Non-limiting examples of alumina sources are high purity alumina, dispersible alumina, precipitated alumina (e.g., alumina cake), hydrotalcite, boehmite alumina, gamma alumina, delta alumina, theta alumina, pseudo boehmite alumina, etc. Non-limiting examples of silicon containing sources are zeolites, quartz, colloidal silica, fly ash, silica nano-particles, microgranular silica particles. Non-limiting examples of organic compounds sources are sugar, starch and all types of cellulose, for example methyl cellulose, ethyl cellulose and propyl cellulose. Non-limiting examples of suitable cationic or anionic clays sources are saponite, bentonite, attapulgite, kaolin, sepiolite, laponite, hectorite, English clay, hydrotalcite and heat- or chemically treated clays such as meta-kaolin. Non-limiting examples of suitable organic silicon sources are silicones (polyorganosiloxanes such as polymethylphenylsiloxane and polydimethylsiloxane), and compounds containing Si-O-C-O-Si structures, silicon oil, and precursors thereof such as methyl chlorosilane, dimethyl chlorosiline, trimethyl chlorosilane. In some embodiments, the at least one additional component is derived or derivable from organic silicon sources. In some preferred embodiments the at least one additional component is derived or derivable from silicon oil. Thus, in some embodiments, the catalyst of the present invention can comprise, as the at least one additional component, silica; silica- alumina; alumina; cationic clays or anionic clays; graphite; graphene; metal silicates having a metal component corresponding to the at least one metal component used, e.g. calcium silicates; sodium silicate, or mixtures thereof. In preferred embodiments, the at least one additional component is derived from silicon containing sources. While not wishing to be bound by theory, the inventors hereof believe that when the additional component is derived or derivable from silicon-containing sources, the at least one metal component interacts with the silicon to form at least one metal silicate, preferably calcium silicate. Again, while not wishing to be bound by theory, the inventors hereof believe that the formation of these metal silicates enhances the performance of the catalyst. Thus, in some preferred embodiments, the catalysts of the present invention also comprise at least one metal silicate, wherein said metal silicate comprises a metal selected from Group IA or Group IIA metal of the Periodic Table, preferably calcium silicate.

[0014] The catalysts of the present invention also optionally comprise, and in some embodiments do comprise, at least one promoter. The at least one promoter can be selected from any promoter effective in transesterification catalysts. Non-limiting examples of suitable promoters include alkali metals, alkaline-earth metals and rare-earth metals. Non-metallic components can also serve as effective promoters, in some embodiments. Suitable alkali metals are K, Li, Na, Rb and Cs. Suitable alkaline- earth metals are Mg, Ca, Sr and Ba. Suitable rare earth metals are Group 3 metals including the lanthanides and actinides. Suitable non-metallic components include C and P. The at least one promoter can be impregnated on the final catalyst composition with an impregnation solution. It should be noted that the at least one promoter is in addition to the metal component discussed above.

[0015] The catalysts of the present invention can also be characterized as having an Accelerated Aging Test ("AAT") value in the range of from about 5 to about 10 and most preferably in the range from about 8 to about 10.AAT values are determined as follows. Firstly, the 0.5 g of catalyst (particles) are shaken for 24 hours in 4 ml biodiesel (FAME). Shaking is done at 60°C in small flasks in a Chemspeed ASW-1000 at 700 rpm. After 24 hours, each liquid is analyzed with ICP to determine the concentrations of metals present. The amount of leached metals is then ranked from 0 to 5, where 0 indicates a high leaching and 5 a very low leaching. The numbers depend on the concentration, as given in Table 1.

Table 1 - Lower and upper boundaries for ranking metal leaching in FAME

Secondly, a visual inspection of the catalyst particles (after shaking) is done, and their physical appearance is described with a number that ranges from 0 (catalyst has dissolved) to 5 (catalyst particles perfectly intact). Values in between are 1 (only powder present), 2 (powder and small pieces visible), 3 (at least about half of the particles are intact), and 4 (only minor particle damage, or particles fallen into a few pieces). Thirdly, for extrudates, the catalyst particles are subjected to a crush strength test to determine the mechanical integrity and strength of the catalyst, expressed as pounds per mm (lbs/mm). The side crush strength is measured according to ASTM D 4179-82. This measurement is scaled to yield a rank ranging from 0 to 5. Finally, the numbers obtained in three tests are averaged to yield the final ranking number, which is multiplied by two to yield the AAT index. Thus, the AAT ranges from 0 (poor stability) to 10 (excellent stability).

[0016] The catalyst composition may have many different shapes. Suitable shapes include powders, spheres, cylinders, rings, and symmetric or asymmetric polylobes, for instance tri- and quadrulobes. Particles resulting from extrusion, beading or pelletizing usually have a diameter in the range of 0.2 to 10 mm, and their length likewise is in the range of 0.5 to 20 mm. Powders, including those resulting from, e.g., spray-drying, generally have a median particle diameter in the range of 1-250 micrometer, preferably 20 to 150 micrometer, but deviations from this general range are possible.

Process for Preparing the Catalyst

[0017] The catalysts of the present invention are preferably prepared by combining at least one metal carbonate selected from carbonates of Group IA of the Periodic Table, Group IIA of the Periodic Table, and mixtures thereof, and at least one additional component, including optional components if so present, thereby forming a catalyst precursor. The at least one, preferably only one, metal carbonate used in this embodiment corresponds to the desired metal component of the catalyst and preferably comprises at least one, more preferably only one, Group IIA metal carbonate, most preferably CaC0₃. The at least one additional component can be any of those described above.

[0018] In another preferred embodiment, the catalysts of the present invention are prepared by combining at least one metal hydroxide selected from hydroxides of Group IA of the Periodic Table, Group IIA of the Periodic Table, and mixtures thereof, and at least one additional component, including optional components if so present, thereby forming the catalyst precursor. The at least one, preferably only one, metal hydroxide used in this embodiment corresponds to the desired metal hydroxide of the catalyst and comprises at least one, more preferably only one, Group IIA metal hydroxide, most preferably Ca(OH)₂. The at least one additional component can be any of those described above. In some embodiments, at least one metal hydroxide and at least one metal carbonate, as described above including preferred embodiments, are used.

[0019] The methods or means by which the metal carbonate and/or hydroxide and at least one additional component are combined include milling, kneading, slurry-mixing, dry or wet mixing, or combinations thereof. In some embodiments, these components are combined by dry mixing, wet mixing, or combinations thereof. By dry mixing, it is meant that the components used to produce the catalyst precursor are present as dry materials prior to combining. If a dry mixing technique is selected, liquids, typically and preferably aqueous liquids, will need to be added to the catalyst precursor prior to shaping. By wet mixing, it is meant that at least one of the components used to produce the catalyst precursor contains a liquid component, sometimes an aqueous component. In preferred embodiments, the components are combined and subjected to mixing and/or kneading, preferably kneading. In other preferred embodiments, the components are combined via a wet mixing technique, preferably slurry mixing, and then kneaded. By "slurry mixing" it is meant that at least one, preferably all, of the components used to produce the catalyst precursor are present as a slurry prior to mixing, preferably an aqueous slurry. Thus, in some embodiments, "slurry mixing" can include adding at least one dry component to a mixing apparatus containing a liquid, preferably aqueous liquid, more preferably water, or the mixing apparatus can contain a slurry preformed from one or more of the catalyst precursor components. In some preferred embodiments, the components are combined and subjected to mixing and/or kneading, preferably kneading, until the catalyst precursor is a homogenous mixture of the catalyst components.

[0020] After the catalyst precursor components have been combined to form the catalyst precursor, the catalyst precursor is subjected to shaping. The method by which the catalyst precursor is shaped can be selected from any shaping technique know to produce catalysts. In some embodiments, the catalyst precursor is shaped by extruding, pelletizing, beading, spray-drying, or any combination thereof. Generally, the shaping step used will depend on the end application of the catalyst. For example, if the catalyst is to be applied in slurry-type reactors, fluidized beds, moving beds, or expanded beds, spray-drying or beading is generally applied. Thus, in some embodiments, it is preferred that the catalyst precursor is subjected to spray drying or beading. For fixed bed or ebullating bed applications, generally the catalyst is extruded, pelletized and/or beaded. Thus, in some embodiments, it is preferred that the catalyst precursor is extruded, pelletized and/or beaded. The shape and size of the catalyst can vary and will typically depend upon the intended application of the catalyst. In some preferred embodiments, the catalyst precursor is spray dried.

[0021] In the shaping step, the amount of liquid should be controlled. For example, if prior to subjecting the catalyst precursor to spray-drying, the amount of liquid is too low, additional liquid must be added. If, on the other hand, e. g., prior to extrusion of the catalyst composition the amount of liquid is too high, the amount of liquid must be reduced by, e. g., solid-liquid separation via, e. g., filtration, decantation, or evaporation and, if necessary, the resulting material can be dried and subsequently re -wetted to the desired extent.

[0022] Once formed, the catalyst precursor can be optionally, and in some embodiments is, dried to remove excess water. If the catalyst precursor is subjected to drying, it is preferred that the temperature of such drying is above 100°C, preferably in the range of from about 100°C to about 200°C, more preferably in the range of from about 100°C to about 150°C, preferably for a period of time up to 24hours.

[0023] In the practice of the present invention, the catalyst precursor, after the optional drying if so employed, is subjected to a thermal treatment. "Thermal treatment" as used herein means that the catalyst precursor is subjected to conditions of elevated temperature for a period of time sufficient to convert at least a portion, but less than substantially all, of the at least one metal carbonate to at least one metal oxide. For example, in the case of CaC0₃, at least a portion of the CaC0₃ starting material is converted to CaO, but at least a portion of the CaC0₃ starting material also remains in the final catalyst composition. The conditions under which the thermal treatment is conducted generally include temperatures of greater than about 500°C, preferably in the range of from about 500°C to about 1000°C, in some embodiments in the range of from about 550°C to about 900°C, and in some embodiments in the range of from about 600°C to about 900°C, and in exemplary embodiments in the range of from about 700°C to about 900°C. The thermal treatment is performed for a time varying from about 0.1 to about 48 hours, preferably in the range of from about 0.2 to about 8 hours, most preferably in the range of from about 0.5 to about 2 hours. The thermal treatment can be conducted in an inert gas such as nitrogen, or in an oxygen containing gas, such as air or pure oxygen, or in a carbon dioxide containing gas, such as air or pure carbon dioxide, or mixtures thereof. The thermal treatment can also be carried out in the presence of steam.

[0024] After the thermal treatment, the catalyst can optionally be subjected to a further or second thermal treatment. If the catalyst is subjected to such a second or further thermal treatment, it is preferred that the temperature of such second or further thermal treatment is in the range of from about 100°C to about 200°C, more preferably in the range of from about 100°C to about 150°C, preferably for a period of time up to 24 hours, more preferably in the range of from about 8 to 16 hours.

[0025] Once formed, the catalyst composition can be subjected to further treatments such as grinding, milling, sieving, or other particle size reduction methods. In some embodiments, the catalyst composition can be used as a component in further catalysts. Use of the Catalyst Compositions of the Present Invention

[0026] The catalyst compositions of the present invention are useful as solid basic catalysts, among other things, catalysts useful in preparing products from bio- feedstreams, in some embodiments products suitable for use as fuel products or biofuels. As used herein, bio-feedstreams include any feedstreams comprising fatty acids and/or mon-, di, or triglycerides. Suitable bio-feedstreams include, but are not limited to, those derived from biological or agricultural sources, those originating from biomass, the like, and mixtures thereof. Other suitable bio-feedstreams include those containing mono-, di- and/or tri-esters of carboxylic acids with chain lengths varying from C₃ to C₃o, branched or unbranched, possibly containing one or more carbon-carbon double/ unstaturated bonds and/or functional groups like hydroxyl, aldehyde, ketone and amine groups at a terminal or internal position. Non-limiting examples of suitable bio-feedstreams include those originating from biomass, preferably plants, algae, other natural products; vegetable oils including waste and fresh cooking oils; animal fats; fish oils; tall oil; fatty acid distillates; the like; and mixtures thereof. In the practice of the present invention, the bio- feedstream can be selected from any of the non-limiting examples of suitable bio- feedstreams or mixtures of one or more. In the practice of the present invention, the bio- feedstream can also be selected from any of those containing as a component any one or more of the non-limiting examples of suitable bio-feedstreams. In some embodiments, the feedstreams can also comprise conventional hydrocarbon sources. In other embodiments, the bio-feedstreams can contain free fatty acids ("FFA"), water or combinations thereof. In some preferred embodiments, the bio-feedstreams contain FFA's in an amount up to about 10wt.% free fatty acids ("FFA") or water in an amount up to about 10wt.% water, or combinations thereof, based on the total weight of the bio- feedstream.

[0027] The bio-feedstream and catalyst composition are preferably contacted under conditions including temperatures in the range of from about 25°C to about 300°C, preferably in the range of from about 25°C to about 120°C, more preferably in the range of from about 50°C to about 70°C, most preferably in the range of about 55°C to 65°C, and in exemplary embodiments in the range of about 58°C to 62°C. The conditions also include pressures, in some embodiments autogenous pressures, in the range of from about 1 to about 300 bar, preferably in the range of from about 1 to about 10 bar, more preferably about 1 to about 2 bar. These conditions can also include space velocities (LHSV) in the range of from about 0.05 to about 10 h^"1.

[0028] In preferred embodiments, the contacting of the bio-feedstream and catalyst composition is conducted in the presence of at least one organic compound that contains one or more hydroxyl groups per molecule, preferably the at least one organic compound is at least one alcohol, more preferably an alcohol containing in the range of from about 1 to about 10 carbon atoms, more preferably 1 to about 5 carbon atoms, most preferably about 1 to about 3 carbon atoms. Preferably, the at least one alcohol contains one or more hydroxyl groups per alcohol molecule. In some preferred embodiments, the at least one organic compound is methanol, and in other preferred embodiments, the at least one organic compound is ethanol. In still other preferred embodiments, the at least one organic compound is methanol and ethanol. In these embodiments, the molar ratio of the at least one organic compound to bio-feedstream is generally in the range of from about 1 to about 500, preferably in the range of from about 1 to about 50, more preferably in the range of from about 1 to about 10, most preferably in the range of from about 3 to about 7.

[0029] The fuel products so produced can comprise, and in some embodiments do comprise, calcium ions. The calcium ions contained in the fuel products can result from multiple or single sources such as the bio-feedstream, the catalyst, etc. These fuel products can comprise up to about 5000wppm calcium ions, in some embodiments from about 100 to about 5000wppm calcium ions, in other embodiments from about 100 to about 2000wppm calcium ions, and in still other embodiments, from about 100 to about 1500wppm calcium ions. In these embodiments, the fuel product can be contacted, and preferably is contacted, with a homogenous acidic material, preferably sulfuric acid. While not wishing to be bound by theory, the inventors hereof believe that the contacting of the fuel product with the homogenous acidic material reduces at least a portion, preferably substantially all, of the calcium ions, and produces calcium sulfates, which can be recovered and removed by, for example, filtration. The homogenous acidic material can suitable be removed by, for example, water washing. In some embodiments, the homogenous acidic material can, and sometimes does, convert at least a portion of any remaining free fatty acids, monoglycerides, and/or diglycerides, to fuel products or biofuel.

[0030] The fuel products and homogenous acidic material are typically contacted under conditions including temperatures of less than about 100°C, preferably in the range of from about 50 to about 100°C, more preferably in the range of from about 60 to about 90°C, most preferably in the range of about 60°C to 80°C, and in exemplary embodiments in the range of about 60°C to about 70°C.

[0029] The above description is directed to several embodiments of the present invention. Those skilled in the art will recognize that other means, which are equally effective, could be devised for carrying out the spirit of this invention. It should also be noted that preferred embodiments of the present invention contemplate that all ranges discussed herein include ranges from any lower amount to any higher amount. The following examples will illustrate the present invention, but are not meant to be limiting in any manner.

EXAMPLES

EXAMPLE 1 Preparation of a catalyst using calcium hydroxide and alumina sources with prolonged heating

[0030] To 2.3 kg of calcium hydroxide, 2.9 kg of an alumina cake (LOI of 75.4 wt%) and 50 g of a hydroxymethylethylcellulose was added in a mixer. During the mixing, the temperature was increased somewhat to reduce the water content of the mixture to obtain an extrudable mix with an extrusion Loss of Ignition (LOI) of 51.3 wt%. The mixture that was obtained was extruded in a 1.5 mm cylindrical shape. Subsequently the sample was dried at 120°C overnight and thermally treated in air at 700°C for 2 hours (using a temperature ramp rate of 5°C/minute). The catalyst obtained was thermally treated in air at 120°C for 12 hours.

EXAMPLE 2 Preparation of a catalyst using calcium hydroxide, alumina sources and additional components with prolonged heating

[0031] 1.8 kg of calcium hydroxide, 2.4 kg of an alumina cake (LOI of 75.4 wt%), 0.6 kg of HY-zeolite and 100 g of a hydroxymethylethylcellulose were added to a kneader. During the mixing, the temperature was increased somewhat to reduce the water content of the mixture to obtain an extrudable mix with an extrusion LOI of 47.1 wt%. The mixture obtained was extruded in a 1.5 mm cylindrical shape. Subsequently the sample was dried at 120°C overnight and thermally treated in air at 700°C for 2 hours (using a temperature ramp rate of 5°C/minute). The catalyst obtained was thermally treated in air at 120°C for 12 hours.

EXAMPLE 3 Preparation of a catalyst according to the invention using calcium carbonate, silica sources and additional components

[0032] To 2.3 kg of calcium carbonate, 0.63 kg of attapulgite (LOI = 20.0%), a needlelike clay mineral composed of magnesium-aluminum silicate having a lateral dimension above 1 micrometer, 1.2 kg water, and 0.2 kg finely ground glass was added. After mixing, 10 g of hydro xymethylpropylcellulose was added and kneading was continued until the desired density was reached, as can be judged by a person skilled in the art. The mixture was shaped using extrusion, and subsequently dried at 120°C overnight and thermally treated in air at 850°C for 2 hours (using a temperature ramp rate of 5°C/minute), leading to strong extrudates. The sample obtained can be used in the catalytic processes as described in this invention.

EXAMPLE 4 Preparation of a catalyst according to the invention using calcium carbonate, silica sources and additional components

[0033] To 2.4 kg of calcium carbonate, 0.68 kg of attapulgite (LOI = 20.0%), a needlelike clay mineral composed of magnesium-aluminum silicate having a lateral dimension above 1 micrometer, lOOg silicon oil, and 32 g of a hydroxymethylpropylcellulose was added in a mixer. Also 1.2 kg of demineralized water was added to the mixture. During the mixing, the temperature was increased somewhat to reduce the water content of the mixture to obtain an extrudable mix, as will be evident to a person skilled in the art. Extrusion LOI was 32.6 wt%. The mixture obtained was extruded in a 1.5 mm cylindrical shape. Subsequently the sample was dried at 120°C overnight and thermally treated in air at 850°C for 2 hours (using a temperature ramp rate of 5°C/minute).

EXAMPLE 5 Preparation of a catalyst according to the invention using calcium carbonate, alumina sources and additional components

[0034] To 3.1 kg of calcium carbonate, 3.0 kg of an alumina cake was added in a kneader. During the mixing, the temperature was increased somewhat to reduce the water content of the mixture to obtain a mix with the desired density as can be judged by a person skilled in the art. It was extruded in a 1.5 mm cylindrical shape. Subsequently the sample was dried at 120°C overnight and thermally treated in air at 850°C for 2 hours (using a temperature ramp rate of 5°C/minute).

EXAMPLE 6 Preparation of a catalyst according to the invention using calcium carbonate and additional components

[0035] To 2.5 kg calcium carbonate, 0.75 kg of attapulgite (LOI = 20.0%), a needle-like clay mineral composed of magnesium-aluminum silicate having a lateral dimension above 1 micrometer, was added in a kneader. 1.2 kg of water was added and followed by 40 g of a hydroxymethylethylcellulose, and the mixture was kneaded until it was dense enough for extrusion. After extrusion, the sample was dried at 120°C overnight and thermally treated in air at 850°C for 2 hours (using a temperature ramp rate of 5°C/minute).

EXAMPLE 7 Preparation of a catalyst according to the invention in powder form

[0036] A powder catalyst was prepared by grinding and sieving the catalyst prepared as described in Example 4 (before calcination) to the desired particle size, in this case 32 to 53 μηι. Calcination of the catalyst material was performed after grinding and sieving, at 850°C for 2h (ramp: 10°C/min).

EXAMPLE 8 Preparation of a catalyst according to the invention using calcium hydroxide, silica sources and additional components

[0037] To 2.0 kg of calcium hydroxide, 0.75 kg of attapulgite (LOI = 20.0%), a needlelike clay mineral composed of magnesium-aluminum silicate having a lateral dimension above 1 micrometer, was added in a mixer. Then, 1.1 kg sodium silicate solution (with a silica content expressed as 28wt% Si02 and a sodium content expressed as 8.5wt% Na20) was added, with 1.2 kg water. In the last addition step, 13 g of a hydroxymethylpropylcellulose was added. During the mixing, the temperature was increased somewhat to reduce the water content of the mixture to obtain an extrudable mix, as will be evident to a person skilled in the art. Extrusion LOI was 46 wt%. Subsequently the sample was dried at 120°C overnight and thermally treated in air at 550°C for 2 hours (using a temperature ramp rate of 5°C/minute). EXAMPLE 9 Preparation of a catalyst according to the invention using calcium carbonate, silica sources and additional components

[0038] To 2.4 kg of calcium carbonate, 0.68 kg of attapulgite (LOI = 20.0%), a needlelike clay mineral composed of magnesium-aluminum silicate having a lateral dimension above 1 micrometer, and 1.25 kg water were added. Subsequently, during mixing, 0.11 kg of a microgranular silica, having a median particle size of 350 micrometer, was added, and finally 32 g of a hydroxymethylpropylcellulose. During mixing, the temperature was increased somewhat to reduce the water content of the mixture to obtain an extrudable mix, as will be evident to a person skilled in the art. Extrusion LOI was 31.8 wt%. The sample was dried at 120°C overnight and thermally treated in air at 850°C for 2 hours (using a temperature ramp rate of 5°C/min).

EXAMPLE 10 Preparation of a catalyst according to the invention using calcium carbonate, silica sources, glucose and additional components

[0039] To 2.1 kg of calcium carbonate, 0.5 kg of attapulgite (LOI = 20.0%), a needle-like clay mineral composed of magnesium-aluminum silicate having a lateral dimension above 1 micrometer, 0.1 kg silicon oil and 0.3 kg glucose was added in a mixer. Also 1.0 kg of water was added to the mixture. During the mixing, the temperature was increased somewhat to reduce the water content of the mixture to obtain an extrudable mix, as will be evident to a person skilled in the art. Extrusion LOI was 38.9 wt%. Subsequently the sample was dried at 120°C overnight and thermally treated in steam at 650°C for 2 hours (using a temperature ramp rate of 5°C/minute).

EXAMPLE 1 1 Preparation of a spray dried catalyst according to the invention, using calcium carbonate and sodium silicate

[0040] A powder catalyst was made according to the following procedure. To a heel of 3.0 kg water, 0.5 kg sodium silicate solution (with a silicon content of 28 wt%, expressed as Si0₂ and a sodium content of 8.5 wt% expressed as Na₂0) was added under vigorous stirring. Due to the risk of gelation of the silicate solution, this step must be performed with care. It is known that silicate solutions are sensitive to gelation and therefore its addition must be done slowly (over a few minutes) while stirring vigorously. This ensures optimal local mixing, and prevents pH-excursions below a pH of about 9. To this mixture 2.8 kg calcium carbonate was added under vigorous stirring with a turbine stirrer, until a mixture was obtained with the appropriate viscosity and flow behavior for spray drying, as will be evident to a person skilled in the art. The mixture had a solid content of 47 wt%. Spray drying temperature was: inlet T = 400°C, outlet T = 140°C, spray-wheel speed was 10,000 rpm, pipeline pressure was about 0.5 bar, and slurry flow speed was 90 liters per hour. The thus obtained catalyst powder was further processed using a wind- sifting device. This instrument separates particles in an airflow on their mass and size, yielding the desired particle size, which can be chosen anywhere between 5 and 181 um. In this case, the finally obtained powder has a median diameter of 65 um. The sample was calcined on a plate in flowing air at 850°C for 2 hours (using a temperature ramp of 10°C/min).

EXAMPLE 12 Preparation of a spray dried catalyst according to the invention, using calcium carbonate and sodium silicate, and a more elaborate washing procedure

[0041] A powder catalyst was made following the description in Example 11 , using a heel of 2.0 kg water, 2.0 kg sodium silicate solution, and 2.8 kg calcium carbonate instead. The resulting slurry had a solid content of 52 wt%. The spray dried powder was further processed using a wind-sifting device to obtain the desired particle size, in this case with a median diameter of 86 um. Subsequent treatment of the catalyst powder was different from Example 11. The powder was mildly calcined in flowing air at 300°C for 2 hours (using a temperature ramp of 5°C/min). Then, a washing procedure was employed to remove excess (non-bound) sodium from the catalyst, using proton-exchanged tap water. The sample thus obtained was dried overnight (125°C) and subsequently calcined at 850°C for 2 hours (using a temperature ramp of 10°C/min).

EXAMPLE 13 Preparation of a spray dried catalyst according to the invention, using calcium carbonate and a colloidal silica dispersion

[0042] To a heel of 5.0 kg water was added 10 kg of a colloidal silica dispersion, with a surface area of 300 m /g. This mixture was stirred with a turbine stirrer to obtain a homogeneous mixture, to which 15 kg calcium carbonate was added under stirring. The precise stirring speed and time may be varied, to ensure optimal mixing of the components. The mixture had a solid content of 58 wt% and was spray dried. Spray drying temperature was: inlet T = 400°C, outlet T = 140°C, spray -wheel speed was 10,000 rpm, pipeline pressure was about 0.5 bar, and slurry flow speed was 90 liters per hour. The spray dried powder was further processed using a wind-sifting device to select the desired particle size, in this case with a median diameter of 69 um. The powder obtained was calcined on a plate in flowing air at 850°C for 2 hours (using a temperature ramp of 10°C/min).

EXAMPLE 14 Preparation of a spray dried catalyst according to the invention, using calcium carbonate, sodium silicate and additional components

[0043] To a heel of 2.5 kg water, 0.6 kg of attapulgite (LOI = 20.0%), a needle-like clay mineral composed of magnesium-aluminum silicate having a lateral dimension above 1 micrometer was added. The mixture was vigorously stirred with a turbine stirrer and left overnight. To this mixture was added 2.8 kg of calcium carbonate, 1.5 kg of sodium silicate solution (with a silica content of 27.9wt% expressed as Si0₂ and a sodium content of 8.5wt% expressed as Na₂0), and more water were added to obtain a slurry with the right viscosity for spray drying, as judged by a person skilled in the art. Due to the risk of gelation of the silicate solution, this step must be performed with care. It is known that silicate solutions are sensitive to gelation and therefore its addition must be done slowly (over a few minutes) while stirring vigorously. This ensures optimal local mixing, and prevents pH-excursions under a pH of about 9. The mixture was spray dried, with inlet T = 400°C and outlet T = 140°C, spray- wheel speed of 10,000 rpm, pipeline pressure of about 0.5 bar, and slurry flow speed of 90 liters per hour. The thus obtained catalyst powder was further processed using a wind-sifting device, to select the desired particle size, in this case with a median value of 94 mm. The powder obtained was calcined on a plate in flowing air at 850°C for 2 hours (using a temperature ramp of 10°C/min).

EXAMPLE 15 Preparation of a spray dried catalyst according to the invention, using calcium carbonate and sodium silicate

[0044] To a heel of 2.4 kg water, 0.5 kg sodium silicate solution (with a silica content expressed as 28wt% Si02 and a sodium content expressed as 8.5wt% Na20) under vigorous stirring. Due to the risk of gelation of the silicate solution, this step must be performed with care. It is known that silicate solutions are sensitive to gelation and therefore its addition must be done slowly (over a few minutes) while stirring vigorously. This ensures optimal local mixing, and prevents pH-excursions below a pH of about 9. To this mixture 2.8 kg calcium carbonate was added under vigorous stirring with a turbine stirrer, until a mixture was obtained with the appropriate viscosity and flow behavior for spray drying, as will be evident to a person skilled in the art. The mixture had a solid content of 51 wt%. Spray drying temperature was: inlet T = 400°C, outlet T = 140°C, spray-wheel speed was chosen to be 16,000 rpm as to tune the desired particle size, pipeline pressure was about 0.5 bar, and slurry flow speed was 90 liters per hour. The thus obtained catalyst powder was further processed using a wind-sifting device, to further select the desired particle size. The sample was calcined on a plate in flowing air at 850°C for 2 hours (using a temperature ramp of 10°C/min).

EXAMPLE 16 Preparation of a spray dried catalyst according to the invention, using calcium carbonate and sodium silicate

[0045] To a heel of 7.3 kg water, 2.8 kg sodium silicate solution (with a silica content expressed as 28wt% Si02 and a sodium content expressed as 8.5wt% Na20) under vigorous stirring. Due to the risk of gelation of the silicate solution, this step must be performed with care. It is known that silicate solutions are sensitive to gelation and therefore its addition must be done slowly (over a few minutes) while stirring vigorously. This ensures optimal local mixing, and prevents pH-excursions below a pH of about 9. To this mixture 7.8 kg calcium carbonate was added under vigorous stirring with a turbine stirrer, until a mixture was obtained with the appropriate viscosity and flow behavior for spray drying, as will be evident to a person skilled in the art. The mixture had a solid content of 49 wt%. Spray drying temperature was: inlet T = 400°C, outlet T = 140°C, spray-wheel speed was chosen to be 16,000 rpm as to tune the desired particle size, pipeline pressure was about 0.5 bar, and slurry flow speed was 90 liters per hour. The thus obtained catalyst powder was further processed using a wind-sifting device, to further select the desired particle size. The sample was calcined on a plate in flowing air at 850°C for 2 hours (using a temperature ramp of 10°C/min).

EXAMPLE 17 Analysis of catalysts with XPS

[0046] X-ray Photoelectron Spectroscopy ("XPS") analyses were performed to measure the calcium carbonate content of the various catalyst samples. After the first thermal treatment step in the preparation of the catalysts of Example 1 and 2, XPS analysis was performed immediately. After 12 hours of reaction with air at 120°C again XPS analysis was performed. As can be seen from the results in Table 2, the amount of CaC0₃ in the catalyst samples increases when the catalyst is kept in air. Furthermore, the catalysts of Example 4 and 6, specifically prepared with CaC0₃, show a calcium carbonate content that is comparable to Examples 1 and 2 after air exposure.

EXAMPLE 18 Evaluation of catalysts with X-Ray Diffraction

[0047] In order to evaluate the stability of the catalysts of the present invention, catalyst samples were prepared according to Example 1 , 2 and 4. After the thermal treatment step of these preparation procedures, the samples were bottled and kept under inert atmosphere. Subsequently, for each of these samples, x-ray diffraction ("XRD") measurements were performed to follow the stability of the catalyst samples during air exposure at ambient humidity and room temperature, via the samples' XRD spectrum. The XRD scans were recorded using a standard powder diffractometer with Ni-KJ5 filter and Cu-Κα radiation.

[0048] Catalyst stability is defined as the amount of CaO phase in the catalyst as found from the XRD spectra, and the decrease of this amount in time is characterized by its half-life. Obviously, a longer half-life means that a catalyst remains stable for a longer time. Table 3 shows the results and demonstrates the superior stability of the catalyst of the present invention. Table 3

Example Half-life (h)

Example 1, before thermal treatment at 120°C 3

Example 1 , after thermal treatment at 120°C 20

Example 2, before thermal treatment at 120°C 3

Example 2, after thermal treatment at 120°C 25

Example 4 77

EXAMPLE 19 Evaluation of catalysts using the AAT

[0049] In order to assess the stability of the catalysts in a fast way, the present materials were tested according to the Accelerated Aging Test (AAT), as described in detail above. Results of the test are shown in Table 4.

[0050] The catalysts of Example 1 and 2 before air exposure have a low amount of calcium carbonate and show a low stability. The catalysts of the present invention, prepared as described in Examples 1 and 2 (after air exposure) and 3 to 16, that have a higher calcium carbonate content, show much higher AAT index, and hence a higher stability. Superior stability is observed for the catalysts of the present invention, Examples 3-16. It can be concluded that the presence of CaC0₃ in the catalysts significantly enhances their stability.

Table 4

Example AAT Index

Example 1 , before thermal treatment at 120°C 2.0

Example 1, after thermal treatment at 120°C 4.8

Example 2, before thermal treatment at 120°C 2.6

Example 2, after thermal treatment at 120°C 5.2

Example 3 9.3

Example 4 8.9

Example 5 8.7

Example 6 8.8

Example 7 8.0 Example 8 7.9

Example 9 8.4

Example 10 9.4

Example 1 1 8.2

Example 12 9.6

Example 13 8.0

Example 14 8.4

Example 15 8.1

Example 16 8.0

Example B 9.5

Example C 4.1

Example D 1.9

Example E 3.6

Example F 7.0

Example G 8.1

EXAMPLE 20 COMPARA TIVE EXAMPLES A - G

[0051] Comparative Example A is blank, no catalyst. Comparative Example B is 100% calcium carbonate. Comparative Example C is 100% calcium hydroxide. Comparative Example D is 100% Portland cement. Comparative Example E is 100% calcium oxide. Comparative Example F is wollastonite (CaSi0₃). Comparative Example G is xonotlite

EXAMPLE 21 Evaluation of the catalysts using XRF

[0052] X-ray fluorescence spectroscopy (XRF) is used to determine the chemical composition of the catalysts of this invention, right after preparation. The results are shown in Table 5. Table 5

Example CaO wt% Si0₂ wt%

1 68.6 <0.1

2 54.4 14.7

3 68.4 21.6

4 71.6 19.5

5 68.1 0.2

6 69.1 21.8

7 71.6 19.5

8 60.9 27.8

9 68.7 22.8

10 75.5 15.9

11 85.6 10.1

12 69.6 23.9

13 67.8 31.3

14 60.0 29.7

15 85.8 10.6

16 78.1 15.9

B 99.9 <0.1

C 99.8 <0.1

D 63.5 20.1

E 99.9 <0.1

F 48.2 50.9

G 49.5 49.1 EXAMPLE 22 Evaluation of catalysts in a Fixed-Bed reactor

[0053] The activity and stability of the catalysts of the examples were tested in a fixed- bed reactor, at different LHSV- values, as follows. A stainless steel tubular reactor, internal diameter 12 mm, was mounted vertically and equipped with a heating mantle to keep the reactor at the desired operating temperature of about 60°C. The reactor was filled with a layer of glass wool and then a layer of carborundum beads at the bottom (to keep the catalyst particles in place), after which 13.5 g of catalyst extrudates were added. Tested catalysts were Examples 1 to 6 and 8 to 10 as described above.

[0054] The reaction mixture that was fed to the reactor was a methanol-rapeseed oil mixture with a molar ratio of 6: 1. The feed was preheated at 60°C in a stirred tank and pumped over the catalyst bed with a flow of 0.12 ml/min, which corresponds to a LHSV (Liquid Hourly Space Velocity/Volume) of 0.25 h ¹. At regular intervals, typically a few times per day, samples were taken from the reactant to measure the amount of Fatty Acid Methyl Esters. The FAME content was determined with gas-chromotography, using a 100%-method. After the required equilibration period the catalyst reached stable conversion levels, with final levels expressed as a percentage of the initial conversion that are presented in Table 6. Catalyst conversion can be tuned as desired by changing the flow speeds and hence the space velocity, see "Chemical Reactor Design and Operation", Westerterp, Van Swaaij, and Beenackers, 2nd Edition, Wiley, New York, 1988, which is incorporated herein in its entirety, for a discussion of performing this task.

[0055] Furthermore, the catalyst described in Example 4 was tested according to the procedure described above. This catalyst showed constant and sustained conversion for more than 40 days, and stayed physically intact. Thus, the presence of CaC0₃ in the catalyst compositions provides for increased catalyst life.

Table 6

Example conversion to FAME

1 93%

2 97%

3 95%

4 100%

5 92%

6 97%

7 100%

8 92%

9 93%

10 100%

1 1 100%

12 100%

13 100%

14 100%

15 100%

A 0%

B 0%

C 0%

D 5%

E 76%

F 0%

G 2%

EXAMPLE 23 Evaluation of catalysts in a slurry tank reactor

[0056] The catalyst prepared as described in Example 7 has been tested in a slurry tank reactor as follows. A round-bottom glass flask, volume 1 liter, was filled with 600 mL rapeseed oil. The oil was heated to 60°C and vigorously stirred with a turbine stirrer. 30 g of catalyst powder and 180 mL of methanol were simultaneously added to the oil. The oil-to-methanol molar ratio was 1 :6. Each 15 min, small samples (<1 mL) were taken to determine the amount of FAME, and hence the progress of the conversion. In one hour, the reaction had reached full conversion of rapeseed oil to FAME as determined by GC analysis (see Table 6) and the reaction was stopped. At the bottom, a clear layer of glycerin was visible.

[0057] The catalysts of Examples 11 to 15 were tested as follows. A small glass flask was filled with 10 ml rapeseed oil and 2.5 ml methanol, to obtain a molar ratio of 1 :6. The mixture was heated and kept at 60°C under vigorous stirring. To the mixture, 0.15 g of the catalyst was added. Small samples (< 500 μΐ) of the mixture were taken to monitor the FAME-conversion. For each catalyst, the reaction also proceeded to full FAME conversion, see Table 6.

EXAMPLE 24 Evaluation of catalysts in a slurry tank reactor, using crude palm oil

[0058] In order to test the catalyst of Example 16 to a crude palm oil feedstream with free fatty acids, a test was performed in a slurry tank reactor as follows. A round-bottom glass flask, volume 500 mL, was filled with 45 mL methanol and 15 g glycerin. The liquid mixture was heated to about 60°C and 7.5 g of the catalyst, prepared as described in Example 16, was added. 150 g of crude palm oil (with a total acid number or TAN, defined as the weight percentage of free fatty acids, of 5.3%), preheated at 60°C, was added and the mixture was vigorously stirred with a turbine stirrer. The oil-to-methanol molar ratio was 1 :6. Each 20 min, small samples (about 1 mL) were taken to determine the amount of FAME and glycerides, and hence to monitor the progress of the conversion. Glyceride conversion was 99.5% in 65 min.

EXAMPLE 25 Evaluation of catalysts in a slurry tank reactor, using a FF A- containing feedstream

[0059] In order to test the resistance of the catalyst of Example 16 of the present invention to a feedstream containing free fatty acids (FFA), a test was performed in a slurry tank reactor. A round-bottom glass flask, volume 500 mL, was filled with 45 mL methanol and 15 g glycerin. The liquid mixture was heated to about 60°C and 7.5 g of the catalyst, prepared as described in Example 16, was added. A mixture of 150 g rapeseed oil and 7.5 g oleic acid was added to the reactor, and the mixture was vigorously stirred with a turbine stirrer. The oil-to-methanol molar ratio was 1 :6. Each 20 min, small samples (about 1 mL) were taken to determine the amount of FAME and glycerides, and hence to monitor the progress of the conversion. In 51 min, 97.4% of the glycerides had been converted.

EXAMPLE 26 Evaluation of catalysts in a slurry tank reactor, using a FFA and water- containing feedstream

[0060] In order to test the catalyst of Example 16 to a feedstream in which water and FFA are present, a test was performed in a slurry tank reactor as follows. A round-bottom glass flask, volume 500 mL, was filled with 45 mL methanol and 15 g glycerin. The liquid mixture was heated to about 60°C and 7.5 g of the catalyst, prepared as described in Example 16, was added. 150 g of crude palm oil (with a TAN of 5.3%) to which 5wt%, of water was added and preheated at 60°C, was added to the reactor and vigorously stirred with a turbine stirrer. The oil-to-methanol molar ratio was 1 :6. Each 20 min, small samples (about 1 mL) were taken to determine the amount of FAME and glycerides, and hence to monitor the progress of the conversion. Glyceride conversion was 96% in 55 min.

EXAMPLE 27 COMPARA TIVE EXAMPLES A - G - Evaluation for trans esterification in a slurry tank reactor

[0061] Firstly, a blank test was performed, this is Example A. In a small glass flask, a mixture of 10 ml rapeseed oil and 2.5 ml methanol (molar ratio 1 :6) was heated to 60°C while vigorously stirring. At regular intervals, samples were taken to determine the FAME content of the mixture by GC analysis. Even after three days, no conversion was observed, see Table 6. In a further test, a small glass flask was filled with 10 ml rapeseed oil and 2.5 ml methanol, to obtain a molar ratio of 1 :6. The mixture was heated and kept at 60°C under vigorous stirring. To the mixture, 0.15 g of catalytic material was added, being (Example B) calcium carbonate, (Example C) calcium hydroxide, (Example D) Portland cement, (Example E) calcium oxide, (Example F) wollastonite, (Example G) xonotlite. Small samples (< 500 μΐ) of the mixture were taken to monitor the FAME- conversion. Table 6 presents the results as found for each of these materials.

[0062] As can be concluded (also from the AAT-index in Table 4), these materials are either (relatively) stable but not active (calcium carbonate, calcium hydroxide, wollastonite, xonotlite), or to some extent active but not stable (Portland cement, calcium oxide), so they all clearly lack the benefits of the catalysts of the present invention, i.e. a combination of high stability and activity, which limits their usefulness as a transesterification catalyst.

EXAMPLES OF HOMOGENOUS ACIDIC CONTACTING OF FUEL PRODUCT STREAMS

[0063] The amounts of methanol and sulfuric acid used are calculated via formula:

(MeOH and FFA ratio 1 : 1 w/w, sulfuric acid is 1 wt% on FFA content).

[0064] While not wishing to be bound by theory, the inventors hereof believe that the Ca ions present in fuel product streams is converted to calciumsulphates that are insoluble in the fuel product stream. These insoluble calciumsulphates can then be effectively removed by, for example, filtration methods. Reaction takes place at 60-85°C

EXAMPLE 28 Contactins a Ca and 10% FFA spiked fuel product stream with sulfuric acid

[0065] In order to test the effect of a homogenous acidic post-treatment step on conversion and purification, a test was performed in a slurry tank reactor. A model feed was prepared as follows: To 107.78 grams of a fuel product stream was added 12.08 grams oleic acid. The fuel product stream used herein was a fatty acid methyl ester ("FAME") originating from a rapeseed stream, and the fuel product stream had a Ca level of 98 wppm. lOOg of the so-prepared model feed was placed in a round bottom flask connected to a water cooled-reflux condenser.

[0066] The contents of the flask were heated to a set temperature of 80°C under agitation at 500rpm. The materials in the flask were continuously and vigorously stirred at 500 RPM while 20 ml of a 1 wt% sulfuric acid (98 wt%) in methanol solution was added. After this addition, the temperature of the mixture decreased to around 70°C. The sample was heated during a period of 2 hrs with agitation continuing.

[0067] After 2 hours, the contents of the flask were allowed to cool to room temperature, and the contents of the flask appeared hazy. The contents of the flask were centrifuged for 20 minutes at 4800 RPM, and after this centrifuging, the contents of the flask looked clear. It is believed that the haziness was caused by precipitated CaS0₄. Spiked FAME FAME product after delta

(with FFA and Ca) sulfuric acid

treatment

C16 + C18 FAMEs 85% 96.3% + 11.3

CI 8 FFA (oleic acid) 12.1% 1% -11.1

Mono, di and tri 2.7% 2.5% -0.2 glycerides

Acid value (mg 15.2 1.2 -92% KOH/g)

Ca level (ppm wt 98 <5* >-97% (mg/kg))

* <5 ppm = below detection limit

EXAMPLE 29 Contacting a crude palm oil FAME product stream with acid

[0068] In order to test the effect of a homogenous acidic post-treatment step on conversion and purification, a test was performed in a slurry tank reactor. A model feed was prepared as follows: 110 microliter of a 18.4 wt% H₂SO₄ in methanol solution was added to 10 ml of a crude palm oil fuel product stream. The fuel product stream used herein was a fatty acid methyl ester ("FAME") originating from crude palm oil, and the fuel product stream had a Ca level of 20 wppm. The so-prepared model feed was placed in a round bottom flask connected to a water cooled-reflux condenser.

[0069] The contents of the flask were heated to a set temperature of 65°C under agitation at 500rpm. The materials in the flask were continuously and vigorously stirred at 500 RPM while 20 ml of a 1 wt% sulfuric acid (98 wt%) in methanol solution was added. After this addition, the temperature of the mixture decreased to around 70°C. The sample was heated during a period of 2 hrs with agitation continuing.

[0070] After 2 hours, the contents of the flask were allowed to cool to room temperature, and the contents of the flask appeared hazy. The contents of the flask were centrifuged for 20 minutes at 4800 RPM, and after this centrifuging, the contents of the flask looked clear. It is believed that the haziness was caused by precipitated CaS0₄. The calcium level was decreased to below detection limit of 5 ppm. Crude palm oil FAME Crude palm oil delta

FAME product after

acidic treatment

C16 + C18 FAMEs 93.6% 98.1% + 4.5

C16 18 FFA 4.7% 1.1% -3.6

Mono, di and tri 1.7% 0.8% -0.9 glycerides

Acid value (mg 12.2 mg KOH/g <1 mg KOH/g >-92% KOH/g)

Claims

WHAT IS CLAIMED

1) A catalyst comprising a metal component containing at least one metal component selected from Group IA metals of the Periodic Table, Group IIA metals of the Periodic Table, and mixtures thereof, and at least one additional component, wherein said metal component comprises at least one oxide and at least one carbonate of the at least one metal.

2) The catalyst according to claim 1 wherein said at least one metal component is at least one Group IIA metal.

3) The catalyst composition according to claim 1 wherein said at least one metal component is Ca.

4) The catalyst composition according to any of the preceding claims wherein said catalyst composition comprises in the range of from about 10wt.% to about 95wt.% of said at least one metal component, calculated on a dry basis as the metal oxide based on the total weight of the catalyst, and wherein said catalyst comprises in the range of from about 25wt.% to about 50wt.% of said at least one carbonate, calculated on a dry basis as the metal carbonate based on the total weight of the catalyst.

5) The catalyst composition according to claim 1 wherein said at least one additional component is selected from silica, silica-alumina, alumina, cationic clays or anionic clays, aluminum stearate, surfactants, graphite, graphene, organic compounds, (poly)silicic acid, sodium silicate, silicon containing components, organic silicon sources, or mixtures thereof.

6) The catalyst composition according to claim 4 wherein said catalyst is further characterized by an AAT value in the range of from about 5 to about 10.

7) The catalyst composition according to claim 1 wherein said at least one additional component is selected from alumina, silica, silica-alumina, attapulgite, sodium silicate, fly ash, ground glass, colloidal silica, microgranular silica and mixtures thereof.

8) The catalyst composition according to claim 7 wherein said catalyst composition comprises at least one metal silicate. 9) The catalyst composition according to claim 1 wherein said catalyst is further characterized by: an AAT value in the range of from about 5 to about 10.

10) The catalyst composition according to claim 1 wherein said at least one additional component is derived or derivable from silica, silica-alumina, alumina, cationic clays or anionic clays, aluminum stearate, silicon oil, graphite, graphene, organic compounds, (poly)silicic acid, sodium silicate, silicon containing components, organic silicon sources, zeolites, or mixtures thereof.

11) A process for preparing a catalyst comprising:

a) combining i) at least one metal carbonate selected from carbonates of Group IA, Group IIA, and mixtures thereof and/or at least one metal hydroxide selected from hydroxides of Group IA, Group IIA, and mixtures thereof; and ii) at least one additional component thereby forming a catalyst precursor;

b) shaping said catalyst precursor to form a shaped catalyst precursor;

c) optionally drying said shaped catalyst precursor;

d) subjecting said shaped catalyst precursor to at least one first thermal treatment thereby forming a catalyst composition comprising a metal component containing at least one metal selected from Group IA metals of the Periodic Table, Group IIA metals of the Periodic Table, and at least one additional component, wherein said metal component comprises at least one oxide and at least one carbonate of the at least one metal; and,

e) optionally subjecting said catalyst composition to at least one second thermal treatment.

12) The process according to claim 1 1 wherein said at least one metal carbonate and/or said at least one metal hydroxide and said at least one additional component are combined by milling, kneading, slurry-mixing, dry or wet mixing, or combinations thereof.

13) The process according to claim 12 wherein said catalyst precursor is kneaded prior to said at least one first thermal treatment.

14) The process according to claim 13 wherein said at least one metal carbonate and/or said at least one metal hydroxide and said at least one additional component are combined by slurry mixing. 15) The process according to any of claims 1 1, 12, or 13 wherein said shaping is selected from extruding, pelletizing, beading, spray-drying, or any combination thereof.

16) The process according to claim 1 1 wherein said optional drying is included in said process, and said optional drying step is conducted at temperatures i) greater than about 100°C; ii) from about 100°C to about 200°C, or iii) in the range of from about 100°C to about 150°C; for a period of time up to about 24 hours.

17) The process according to claim 15 wherein said optional drying is included in said process, and said optional drying step is conducted at temperatures i) greater than about 100°C; ii) from about 100°C to about 200°C, or iii) in the range of from about 100°C to about 150°C; for a period of time up to about 24 hours.

18) The process according to claim 15 wherein said at least one first thermal treatment includes temperatures of i) greater than about 500°C; ii) in the range of from about 500°C to about 1000°C, iii) in the range of from about 550°C to about 900°C; iv) in the range of from about 600°C to about 900°C, or v) in the range of from about 700°C to about 900°C, optionally in the presence of steam, for a period of time in the range of from about 0.1 to about 48 hours.

19) The process according to any of claims 1 1, 12, 13, or 17 wherein said process includes said at least one second thermal treatment and said at least one second thermal treatment is conducted at temperatures in the range of i) from about 100°C to about 200°C, or ii) in the range of from about 100°C to about 150°C; optionally in the presence of steam, for a period of time up to about 24 hours.

20) The process according to any of claims 1 1 or 12, wherein said catalyst composition is subjected to at least one further processing selected from grinding, milling, sieving, or other particle size reduction methods.

21) The process according to claim 19, wherein said catalyst composition is subjected to at least one further processing selected from grinding, milling, sieving, or other particle size reduction methods.

22) The process according to claim 19 where a) is at least one metal hydroxide, and said process includes said optional drying step.

23) A process comprising contacting a bio-feedstream with a catalyst comprising a metal component containing at least one metal selected metal from Group IA metals of the Periodic Table, Group IIA metals of the Periodic Table, and mixtures thereof, and at least one additional component, wherein said metal component comprises at least one oxide and at least one carbonate of the at least one metal thereby producing a fuel product stream, and optionally contacting said fuel product stream with a homogenous acidic material.

24) The process according to claim 23 wherein said bio-feedstream comprises fatty acids and/or mon-, di, and/or triglycerides.

25) The process according to claim 23 wherein said at least one metal component is a Group IIA metal and said catalyst composition comprises in the range of from about 10wt.% to about 95wt.% of said at least one metal component, calculated on a dry basis as the metal oxide based on the total weight of the catalyst, wherein said catalyst composition comprises in the range of from about 25wt.% to about 50wt.% of said at least one carbonate calculated, on a dry basis as the metal carbonate based on the total weight of the catalyst.

26) The process according to claim 23 wherein said metal component is Ca.

27) The process according to any of claims 23, 24, or 25 wherein said bio-feedstream is selected from those originating from biomass, plants, algae, other natural products; vegetable oils including waste and fresh cooking oils; animal fats; tall oil; fatty acid distillates; the like; and mixtures thereof.

28) The process according to claims 23 wherein the contacting of said bio-feedstream and said catalyst composition occurs in the presence of at least one organic compound that contains one or more hydroxyl groups per molecule.

29) The process according to claim 23 wherein the contacting of said bio-feedstream and said catalyst composition occurs in the presence of at least one alcohol containing in the range of from about 1 to about 10 carbon atoms.

30) The catalyst composition according to claims 29 wherein said alcohol is ethanol, methanol, or mixtures thereof.

31) The process according to any of claims 23, 24, or 25 wherein the bio-feedstream and catalyst composition are contacted under conditions including temperatures i) in the range of from about 25° to about 300°C; ii) in the range of from about 25 to about 120°C; iii) in the range of from about 50 to about 70°C; iv) in the range of about 55°C to 65°C; or v) in exemplary embodiments in the range of about 58°C to 62°C.

32) The process according to any of claims 23, 25, 28, 29, or 30 wherein the bio- feedstream is selected from:

a) those containing mono-di and tri-esters of carboxylic acids with chain lengths varying from C₃ to C₃o, branched or unbranched, possibly containing one or more carbon-carbon double/ unstaturated bonds and/or functional groups like hydroxyl, aldehyde, ketone and amine groups at a terminal or internal position;

b) those comprising components derived from biological or agricultural sources, those originating from biomass, the like, and mixtures thereof; or

c) those containing up to about 10wt.% free fatty acids ("FFA") or up to about 10wt.% water, or combinations thereof, based on the total weight of the bio- feedstream.

33) The process according to any of claims 23-26 or 28-30 wherein said process comprises contacting said fuel product with said homogenous acidic material.

34) The process according to claim 33 wherein said contacting converts at least a portion of any calcium ions contained in the fuel products.

35) The process according to claim 33 wherein said homogenous acidic material is sulfuric acid.

36) The process according to claim 33 wherein said contacting with said homogenous acidic material produces at least calcium sulfates and said process further comprises one or more filtering stages or steps to remove at least a portion of said calcium sulfates.

37) The process according to claim 33 wherein said contacting with said homogenous acidic material converts at least a portion of any remaining free fatty acids, monoglycerides, and/or diglycerides, to fuel products or biofuel.

38) The process according to claim 32 wherein said process comprises contacting said fuel product with said homogenous acidic material, said contacting converts at least a portion of any calcium ions contained in the fuel products, said contacting with said homogenous acidic material converts at least a portion of any remaining free fatty acids, monoglycerides, and/or diglycerides, to fuel products or biofuel, and said process optionally comprises one or more filtering stages or steps to remove at least a portion of said calcium sulfates.

39) The process according to claim 31 wherein said process comprises contacting said fuel product with said homogenous acidic material, said contacting converts at least a portion of any calcium ions contained in the fuel products, said contacting with said homogenous acidic material converts at least a portion of any remaining free fatty acids, monoglycerides, and/or diglycerides, to fuel products or biofuel, and said process optionally comprises one or more filtering stages or steps to remove at least a portion of said calcium sulfates.