Catalyst and related reaction process for producing wax - Patents.com

Abstract

Provided herein is a method for preparing a biowax, comprising: (i) providing a raw material containing one or more fatty acids having 12 to 22 carbon atoms; and (ii)(a) a layered double oxide; (b) a binder; subjecting said feedstock to a ketonization reaction catalyzed by a composite catalyst material comprising: A method is disclosed that includes:

Description

[Technical Field]

[0001] The present invention relates to novel catalysts and related methods for converting carboxylic acids and related biolipids / fatty acids derived from plant or animal oils into waxes (e.g., biowaxes, or non-biowaxes or partially biowaxes when based on fossil-fuel-derived chemical feedstocks). More specifically, in contrast to conventional methods requiring solvents, the method of the present invention involves a solvent-free decarboxylation coupling reaction in which two carboxylic acid molecules react to form a ketone, with carbon dioxide and water as by-products. The present invention also discloses a high-performance catalyst in pellet form containing Mg-Al layered double oxide (LDO) as the active component and a binder (e.g., clay). Furthermore, the catalyst of the present invention has been tested under rigorous conditions in a continuous-flow packed-bed reactor for over 500 hours. [Background technology]

[0002] The listing of previously published documents cited in this specification and the discussion therein need not necessarily be acknowledged as forming part of the state of the art or common general knowledge.

[0003] Paraffin wax plays a vital role in a wide range of applications, including candles, packaging, coatings, cosmetics, emulsions, rubber, phase change materials, and lubricants. This has led to a very high demand for paraffin wax supplies. However, as global oil supplies decline, there is an urgent need to develop alternative pathways that can reduce unsustainable fossil fuel consumption. In this context, the development of biowax and its applications are being widely explored by researchers. The development of sustainable pathways aimed at producing bio-based compounds from renewable feedstocks is of paramount importance as a strategy to compensate for the inevitable depletion of fossil resources in the near future.

[0004] Biowax production begins with bio-based feedstocks derived from biomass or bio-derived lipids. Biomass feedstocks primarily include lignin, starch, lignocellulose, sugars, fats, and oils, which are advantageous for the production of intermediate chemicals such as esters, acids, ketones, and alcohols. Biowax can be produced from a variety of plant oils, including rapeseed oil, soybean oil, sunflower oil, palm oil, coconut oil, waxes, esters, and plant-derived polymeric carbohydrates. For example, palm oil and palm-derived bio-based feedstocks are the primary source of feedstock for biofuels (biodiesel and green diesel) and other biochemicals, particularly in the oleochemical industry based in Southeast Asia. Palm fatty acid distillate (PFAD) is a by-product of palm oil extraction. PFAD accounts for up to 5% of the raw material input and is considered an unwanted processing residue, with palmitic acid accounting for the largest proportion (over 45%).

[0005] The highly paraffinic structure of PFAD makes it suitable for conversion to paraffinic hydrocarbon products. However, due to its high oxygen content, PFAD needs to be modified to become a viable starting material for fuel, lubricant, or other oleochemical synthesis. One catalytic pathway available for the conversion of such oxygenated compounds is via ketonization, which requires the use of heterogeneous catalysts. In ketonization, carboxylic acids are converted via decarboxylative carbon coupling to form a new C-C bond, producing alkanones, carbon dioxide (CO2), and water (HO) (Figure 1). Hydrogen is not required for the ketonization of carboxylic acids. RCOOH + RCOOH → R2CO + CO2+ H2O(1) RCOOH + R'COOH → R2CO + R'2CO + RR'CO + CO2+ H2O(2)

[0006] Existing catalysts and ketonization methods suffer from several drawbacks. i. The focus is on short-chain carboxylic acids. Typically, the raw material is C1-C5 (or C12 less than 100%) and does not focus on long-chain carboxylic acids. ii. It is a method that requires large amounts of solvent, typically requiring dilution of the lipid / biological fatty acid feedstock with solvents such as hexane, dodecane, xylene, etc. iii. The catalysts used are usually monometallic or bimetallic catalysts capable of affording the desired ketone in moderate to low yield. iv. There are no commercially available catalysts that have been demonstrated to be capable of converting long-chain carboxylic acids to long-chain ketones with good conversion, good yield, and good selectivity in a continuous reaction system in the absence of a solvent.

[0007] Therefore, there is a need for a pelletized catalyst formulation that can overcome the above-mentioned drawbacks. Summary of the Invention [Means for solving the problem]

[0008] Aspects and embodiments of the present invention are described with reference to the following numbered sections. 1. A method for preparing a wax, comprising: (i) providing a raw material containing one or more fatty acids having 2 to 22 carbon atoms; and (ii)(a) a layered double oxide; (b) a binder; subjecting said feedstock to a ketonization reaction catalyzed by a composite catalyst material comprising: A method comprising: 2. The method according to item 1, wherein step (ii) is carried out in the absence of a solvent. 3. The one or more fatty acids are selected from monocarboxylic acids and dicarboxylic acids; The monocarboxylic acid may have 12 to 22 carbon atoms, The dicarboxylic acid may have 2 to 11 carbon atoms. Item 1 or 2. The method according to item 1 or 2. 4. The method according to Item 3, wherein when the one or more fatty acids are monocarboxylic acids only, the wax has one or more components having 23 to 43 carbon atoms, the wax may be a biowax, and the biowax may have one or more components having 23 to 43 carbon atoms. 5. The binder is a clay, which may be a montmorillonite clay, which may be montmorillonite K30, and / or the layered double oxide is in the form of a plurality of particles uniformly dispersed throughout the composite catalyst material; 5. The method of any one of the preceding clauses. 6. The method of any one of the preceding clauses, wherein the composite catalyst material is in the form of pellets. 7. The layered double oxide is formed from a combination of a divalent metal cation, a trivalent metal cation, and an oxygen atom, the divalent metal cation is selected from one or more of the group consisting of magnesium, copper, zinc, nickel, and manganese; the trivalent metal cation is selected from one or more of the group consisting of aluminum, iron, and chromium; The layered double oxide may be a magnesium-aluminum layered double oxide. 5. The method of any one of the preceding clauses. 8. The composite catalyst material is (a) 30 to 50 wt. % of the layered double oxide; (b) 50 to 70 wt.% of the binder; Item 10. The method of any one of the preceding items, comprising: 9. step (ii) is carried out in the absence of a solvent, and / or the binder is a clay, for example, a montmorillonite clay; 5. The method of any one of the preceding clauses. 10. The method of any one of the preceding paragraphs, wherein step (ii) is carried out at a temperature of 350 to 450°C, such as a temperature of 380 to 420°C, for example at a temperature of about 400°C. 11. The method of any one of the preceding paragraphs, wherein step (ii) is carried out at a liquid hourly space velocity (LHSV) of 0.8 to 1.2. 12. The method of any one of the preceding clauses, wherein the feedstock is one or more of a fossil fuel-derived feedstock and a biologically-derived feedstock, and may include a vegetable fatty acid distillate (VFAD) (e.g., palm fatty acid distillate (PFAD)). 13.(a) Layered double oxides and (b) a binder; A composite catalyst material comprising: 14. The composite catalyst material according to item 13, wherein the binder is clay, which may be montmorillonite clay or montmorillonite K30. 15. The composite catalyst material according to item 13 or 14, wherein the layered double oxide is in the form of a plurality of particles uniformly dispersed throughout the composite catalyst material. 16. The composite catalyst material according to any one of items 13 to 15, wherein the layered double oxide is a magnesium-aluminum layered double oxide. 17.(a) 30-50 wt.% of said composite material; (b) 50 to 70 wt.% of the binder; Item 17. The composite catalyst material according to any one of items 13 to 16, comprising: 18. The composite catalyst material according to any one of items 13 to 17, which is in the form of pellets. 19. A method for forming a composite catalyst material according to any one of items 13 to 18, comprising: (a) providing a mixture comprising a layered double oxide, a binder, a plasticizer, a lubricant, and a deflocculating agent; (b) calcining the mixture for a certain period of time to obtain the composite catalyst material. Including, a method. 20. The method according to item 19, wherein the plasticizer is a material containing polar and / or non-polar functional groups, and may be water. 21. The method of claim 19 or 20, wherein the lubricant is a diol. 22. The method according to any one of items 19 to 21, wherein the peptizer is an acid, which may be an inorganic acid. [Brief explanation of the drawings]

[0009] [Figure 1] Shows homoketonization and transketonization reactions. [Figure 2] (a) Possible reactions and reaction pathways, and (b) the morphology and characteristics of Mg-Al-derived layered double oxides (LDOs) observed by field emission scanning electron microscopy (FE-SEM). [Figure 3] The morphology of Mg-Al derived layered double oxide (LDO)-clay composite catalyst pellets observed with a field emission scanning electron microscope (FE-SEM) and energy dispersive X-ray analysis (EDX) are shown. [Figure 4] The adsorption and desorption isotherms of N2 are shown. [Figure 5] The CO2 profile obtained by temperature programmed desorption (TPD) is shown. [Figure 6] NH3 profile by temperature programmed desorption (TPD) is shown. [Figure 7] 1 shows the configuration of a continuous flow packed bed reactor. [Figure 8] 1 shows the catalytic performance of Mg-Al derived LDO-clay composite catalysts over a period of more than 500 hours. DETAILED DESCRIPTION OF THE INVENTION

[0010] It has surprisingly been found that the use of a composite catalyst material in a method for forming a wax may solve all or some of the above problems. Thus, in a first aspect of the present invention there is provided a method for preparing a wax comprising the steps of: (i) providing a raw material containing one or more fatty acids having 2 to 22 carbon atoms; and (ii)(a) a layered double oxide; (b) a binder; subjecting said feedstock to a ketonization reaction catalyzed by a composite catalyst material comprising: The present invention provides a method comprising:

[0011] In the embodiments described herein, the term "comprising" may be interpreted to require the features described herein, but not to limit the presence of other features. Alternatively, the term "comprising" may relate to a situation in which only the components / features described herein are present (e.g., the term "comprising" may be replaced with the terms "consisting of" or "essentially consisting of"). It is expressly intended that both such broad and narrow interpretations are applicable to all aspects and embodiments of the present invention. In other words, the term "comprising" and its equivalents may be replaced with the terms "consisting of" or "substantially consisting of," and vice versa.

[0012] As used herein, the term "substantially consisting of" and synonyms thereof may be interpreted to mean a material that may contain trace amounts of impurities. For example, the purity of this material may be 90% or more, such as greater than 95%, such as greater than 97%, such as greater than 99%, such as greater than 99.9%, such as greater than 99.99%, such as greater than 99.999%, or such as 100% purity.

[0013] Any suitable layered double oxide may be used in the present invention. The layered double oxide may be formed by combining a suitable combination of divalent and trivalent metal cations with oxygen atoms. Suitable divalent metal cations include, but are not limited to, magnesium, copper, zinc, nickel, manganese, and combinations of these divalent metal cations. Suitable trivalent metal cations include, but are not limited to, aluminum, iron, chromium, and combinations of these trivalent metal cations. In an embodiment that may be mentioned herein, the layered double oxide may be a magnesium-aluminum layered double oxide.

[0014] Any suitable binder may be used herein as long as it can withstand calcination and the reaction temperatures to which the composite catalyst material is exposed in the method of the present invention. For example, the binder may be any type of clay. In certain embodiments that may be mentioned herein, the binder may be montmorillonite clay. Examples of montmorillonite clays that may be mentioned herein include, but are not limited to, montmorillonite K30.

[0015] The layered double oxide contained in the composite catalyst material of the present invention may be in any suitable form, for example, the layered double oxide may be in the form of a plurality of particles (e.g., nanoparticles) which may be uniformly dispersed throughout the composite catalyst material.

[0016] The composite catalyst material of the present invention may be used in any suitable form depending on the reactor vessel into which the composite catalyst material is introduced. For example, the composite catalyst material may be applied as a coating on the wall of a continuous flow reactor or may be provided in the form of pellets. In certain embodiments that may be mentioned herein, the composite catalyst material may be in the form of pellets.

[0017] The composite catalyst material of the present invention may contain an appropriate amount of layered double oxide and a binder. For example, the composite catalyst material of the present invention may contain: (a) 30 to 50 wt.% of a layered double oxide; (b) 50-70 wt.% binder; may also include:

[0018] Although a solvent may be used in the methods disclosed herein, it is preferred not to use a solvent, and therefore in embodiments that may be disclosed in the present invention, step (ii) may be carried out in the absence of a solvent.

[0019] Any suitable raw material may be used herein. For example, the raw material may be derived from fossil fuels and / or may be biologically derived (e.g., vegetable oil (e.g., palm oil) or animal oil or related biological lipids / fatty acids derived from other biological sources). In certain embodiments that may be mentioned herein, the raw material may include vegetable fatty acid distillate (VFAD) (e.g., palm fatty acid distillate (PFAD)). In certain embodiments, the raw material may be PFAD.

[0020] As used herein, the term "fatty acid" may refer to any fatty acid material. For example, each fatty acid referred to herein may be a monocarboxylic acid having 12 to 22 carbon atoms or a dicarboxylic acid having 2 to 11 carbon atoms. The fatty acid may be a saturated fatty acid or an unsaturated fatty acid. Additionally or alternatively, the fatty acid may be a branched-chain fatty acid or a straight-chain fatty acid. The wax obtained by the method of the present invention may be any suitable wax. For example, the wax may be a biowax, a non-biowax, or a partially biowax, depending on the raw material used. The wax may also be a wax having one or more components having 23 to 43 carbon atoms. For example, the wax may be a biowax. In certain embodiments that may be mentioned herein, the wax obtained by the method of the present invention may be a biowax having one or more components having 23 to 43 carbon atoms.

[0021] In certain embodiments that may be mentioned herein, when the wax is formed from raw materials containing only monocarboxylic acids, the wax may have one or more components having 23 to 43 carbon atoms.

[0022] In certain embodiments that may be mentioned herein, step (ii) of the process of the present invention may be carried out in the absence of a solvent, and / or the binder may be any type of clay, for example, montmorillonite clay, and / or the layered double oxide may be dispersed throughout the composite catalyst material.

[0023] The methods disclosed herein may be carried out at any suitable temperature, for example, step (ii) of the methods of the present invention may be carried out at a temperature of 350-450°C, such as 380-420°C, for example, at about 400°C.

[0024] The methods disclosed herein may be carried out at any suitable liquid hourly space velocity (LHSV). For example, step (ii) of the methods of the present invention may be carried out at an LHSV of 0.8 to 1.2.

[0025] As will be appreciated, the method disclosed herein is carried out by using a composite catalyst material. Accordingly, in a second aspect of the present invention, (a) a layered double oxide; (b) a binder; A composite catalyst material is provided, comprising:

[0026] As will be appreciated, embodiments of the composite catalyst material have been described above and will not be discussed here for the sake of brevity.

[0027] In a third aspect of the present invention, there is provided a method of forming a composite catalyst material as described herein, comprising the steps of: (a) providing a mixture comprising a layered double oxide, a binder, a plasticizer, a lubricant, and a deflocculating agent; (b) calcining the mixture for a certain period of time to obtain the composite catalyst material. A method is provided that includes:

[0028] The layered double hydroxide (LDH) may be any suitable LDH capable of forming the layered double oxide described above.

[0029] The plasticizer may be any suitable plasticizer material. For example, the plasticizer may be a material that contains polar and / or non-polar functional groups and can be used as a plasticizer. Examples of suitable materials include, but are not limited to, water, polyethylene glycol, and hydroxyethyl cellulose.

[0030] The lubricant may be any suitable lubricant material. For example, the lubricant may be a diol that can be used as a lubricant. Examples of suitable lubricants include, but are not limited to, triethylene glycol, ethylene glycol, glycerin, graphite, mineral oil, propylene glycol, and aluminum stearate.

[0031] The peptizing agent may be any suitable peptizing agent material. For example, the peptizing agent may be an acid that can be used as a peptizing agent. Examples of suitable acids may be inorganic or organic acids, such as inorganic acids. Inorganic acids that may be disclosed herein include, but are not limited to, nitric acid, hydrochloric acid, sulfuric acid, boric acid, and phosphoric acid. Organic acids that may be disclosed herein include, but are not limited to, acetic acid, citric acid, and formic acid.

[0032] The mixture comprises: (a) 30 to 50 wt.% of a layered double oxide; (b) 50-70 wt.% binder; may also include:

[0033] Further, the mixture (c) 5 to 50 wt.% of a plasticizer; (d) 5 to 20 wt.% of a lubricant; (e) 5 to 20 wt.% deflocculant; may also include:

[0034] The amounts of the above materials (c), (d) and (e) are relative amounts with respect to the total amount of the layered double oxide and binder being 100 wt.%.

[0035] Further aspects and embodiments will be described with reference to the following embodiments, but the invention is not limited to these embodiments. [Example]

[0036] material Magnesium nitrate hexahydrate and aluminum nitrate nonahydrate were purchased from Systerm. Synthetic grade urea and Montmorillonite K30 were purchased from Sigma-Aldrich. 65% nitric acid was purchased from EMSURE-Merck. 99% triethylene glycol was purchased from ACRO Organics. Palmitic acid was purchased from R&M.

[0037] Example 1. Synthesis of Mg-Al derived layered double oxide (LDO) LDO is a typical host material for the synthesis of inorganic nanosheets and is generally obtained from the brucite structure (Figure 2). The novelty of LDO lies in its two-dimensional sheet-like compound structure, which has the following characteristics: The increased surface area results in more exposed active sites. Improved dispersion / distribution of catalytic active sites within the LDO.

[0038] The Mg—Al-derived LDO powder can be prepared by any of the following procedures: It will be appreciated that, where necessary, specific amounts may be referenced from the following academic papers (particularly those relating to the preparation of LDO), which are incorporated herein by reference:

[0039] Basic procedure for the synthesis of Mg-Al-derived LDO A certain amount of magnesium nitrate hexahydrate was dissolved in distilled water. Next, a certain amount of aluminum nitrate nonahydrate was added to this solution while vigorously stirring. While vigorously stirring this mixture, urea dissolved in distilled water was added dropwise. The resulting mixture was transferred to an autoclave reactor and heated with stirring at 60°C to 150°C for 1 to 6 hours. The resulting Mg-Al-derived LDH was washed several times with distilled water and ethanol and dried overnight at 100°C. The resulting material was calcined in air to form an Mg-Al-derived layered double oxide.

[0040] Zhu, B. et al., Water Sci. Technol. 2018, 78, 1179-1188 Magnesium nitrate hexahydrate (10.256 g, 40 mmol) was dissolved in distilled water (60 mL). To this solution, aluminum nitrate nonahydrate (3.752 g, 10 mmol) was added while vigorously stirring. To this mixture, urea (6.72 g, 112 mmol) dissolved in distilled water (60 mL) was added dropwise while vigorously stirring. The resulting mixture was transferred to an autoclave reactor and heated at 150 °C with stirring for 6 hours. The resulting Mg-Al-derived LDH was washed several times with ethanol and dried at 100 °C overnight. The resulting catalyst was then calcined in air at 500 °C for 5 hours to form the Mg-Al-derived layered double oxide.

[0041] Jiang, B. et al., Catal. Sci. Technol. 2019, 9, 6335-6344 Appropriate amounts of magnesium nitrate hexahydrate and aluminum nitrate nonahydrate were dissolved in distilled water. An alkaline solution consisting of sodium hydroxide and sodium carbonate was prepared. Both solutions were simultaneously added to a vessel containing 200 mL of water at 25°C and vigorously stirred. After precipitation, the suspension was kept at room temperature for 15 hours and then vigorously stirred at 80°C. The precipitate was then repeatedly washed with deionized water and dried overnight at 100°C. The resulting catalyst was then calcined in air to form a Mg-Al layered double oxide.

[0042] Kocik, J. et al., Mol. Catal. 2021, 516, 111946-111956 A catalyst precursor consisting of a metal nitrate solution (Mg / Al) with a constant Mg:Al molar ratio (e.g., 1:1, 2:1, 3:1, or 4:1) was continuously added to the reactor along with a basic solution (K2CO3 / KOH). The reaction mixture was maintained at 60 °C, pH 9.5, and 250 rpm for 1 hour. The resulting product was then filtered by pressure filtration using a filter press equipped with S15N filter plates. The paste-like product was then washed with deionized water and dried at 65 °C for 12 hours. The resulting catalyst was then calcined in air to form the Mg-Al-derived layered double oxide.

[0043] Example 2. Synthesis of composite catalyst containing Mg-Al-derived LDO and clay Mg-Al LDO powder (prepared in Example 1) and clay powder (binder) were thoroughly mixed in the desired ratio (e.g., 3:7 or 5:5) until homogeneous. An aqueous HNO solution was prepared by mixing the optimal amount of distilled water (plasticizer) and 65% nitric acid (deflocculant, inorganic acid) in a graduated cylinder. Next, triethylene glycol (lubricant, diol) was added and thoroughly mixed. The resulting liquid mixture was added to the above powder mixture and thoroughly mixed until a paste was formed. The paste was loaded into an extruder and extruded at a speed of 50 rpm using a 1 mm diameter die. The extrudates were dried overnight at a temperature above 100°C (e.g., 106°C) and then calcined in air at 500°C for 4 hours.

[0044] The pelletized composite catalyst contained Mg-Al derived LDO as the active component and clay as a binder, mixed with lubricant, plasticizer and deflocculant (Table 1). [Table 1]

[0045] The resulting high performance catalyst in the form of pellets contains Mg-Al LDO as the active component and a clay-based binder.

[0046] Alternatively, LDH may be used in place of LDO in the above preparation, and after calcination, LDO is formed from the LDH.

[0047] Example 3. Catalyst analysis and characterization The Mg-Al LDO powder (prepared in Example 1) and the Mg-Al LDO-clay composite catalyst pellets (prepared in Example 2) were characterized.

[0048] FESEM-EDX The morphological composition of each catalyst was obtained by field emission scanning electron microscopy-energy dispersive X-ray analysis (FESEM-EDX). FESEM images were taken using a LEO 1455 VP electron microscope. The sample catalyst was dispersed on tape attached to an aluminum sample holder. The dispersed sample was then coated with a thin layer of platinum to allow for sample imaging without distortion due to charging effects. The elemental composition of the synthesized catalysts was determined by energy dispersive X-ray analysis (EDX) using a Rayny EDX-720 spectrometer.

[0049] Brunauer-Emmett-Teller (BET) method The surface area and pore characteristics were calculated by the BET method using the Micromeritics ASAP 2020 model. Each catalyst was degassed at 150°C for 8 hours (overnight) to remove moisture and foreign gases adsorbed on the surface of each catalyst. The adsorption and desorption process of N2 on the catalyst surface was analyzed in a vacuum chamber at temperatures ranging from 50°C to 900°C. The pore size distribution of the catalyst was calculated using the Barrett-Joyner-Halenda (BJH) method.

[0050] Gas chromatography-flame ionization detection (GC-FID) A aliquot of sample was added to a 10 mL volumetric flask. 100 μL of internal standard (which could be heptane) was added to the volumetric flask, followed by addition of chloroform to the 10 mL mark. The solution was then filtered and transferred to a small GC vial for analysis.

[0051] TPD The acidity and basicity of each synthesized catalyst were analyzed using temperature-programmed desorption (TPD). A Thermo Finnigan TPD / R / O 1100 (fully equipped with a TCD detector) was used to characterize the basic sites of the catalyst by temperature-programmed desorption with carbon dioxide (TPD-CO2). The catalyst (approximately 0.05 g) was pretreated at 250 °C for 30 min under N2 gas flow. The catalyst was then exposed to CO2 gas at ambient temperature for 1 h to allow CO2 molecules to adsorb onto the catalyst surface. Excess CO2 was then flushed with N2 gas flow at 20 mL / min for 30 min. The TCD detector was used to detect CO2 desorption from the basic sites of the catalyst under helium gas flow (30 mL / min) over a temperature range from 50 °C to 900 °C, with a 30-min hold time. Similarly, to perform temperature-programmed desorption with ammonia (TPD-NH3), ammonia was used as the probe gas, and the adsorption-desorption method was performed in the same manner as the TPD-CO2 step. The desorption peaks obtained from these analyses were used to determine the acidity and basicity of the catalyst.

[0052] Results and Discussion Figure 3 shows the morphology observation and EDX mapping of the Mg-Al-derived LDO-clay composite catalyst pellets by FE-SEM. Figure 4 and Table 2 show the surface area of ​​each catalyst analyzed by the BET method. [Table 2]

[0053] The pelletized catalyst exhibits a higher surface area than the powder form. Calcination increased the surface area and pore volume of the catalyst.

[0054] Figures 5 and 6 show the acidity and basicity of the Mg-Al-derived LDO-clay composite catalyst analyzed by TPD. Figures 5 and 6 indicate that this composite catalyst exhibits moderate acidity / basicity (300–500 °C). Without wishing to be bound by theory, this moderate acidity / basicity is thought to be important for the adsorption and desorption of raw materials to the active sites. The Mg-Al-derived LDO-clay composite catalyst exhibits a characteristic acidic peak (moderately strong acid sites) between 300 and 500 °C and a characteristic basic peak (moderately strong basic sites) between 300 and 500 °C. Therefore, the Mg-Al-derived LDO-clay composite catalyst exhibits a good balance of acidity and basicity, resulting in high selectivity for ketone production (see Example 4).

[0055] Example 4. Catalytic decarboxylation of biologically derived fatty acids The LDO catalyst has high ketonization performance. 12 ~C 22 The robustness of the catalyst in producing the desired biowax in the presence of the feedstock was tested. As will be appreciated, any suitable fatty acid feedstock (derived from a suitable source) may be used to produce the wax according to the methods disclosed herein, and the wax produced is not necessarily limited to biowax. Furthermore, dicarboxylic acids having 2 to 11 carbon atoms may also be reacted. Additionally or alternatively, the fatty acid may be saturated or unsaturated. Additionally or alternatively, the fatty acid may be branched or straight-chain.

[0056] Catalytic decarboxylation of bio-derived fatty acids in a continuous flow packed bed reactor The catalyst performance was evaluated by investigating the ketonization of carboxylic acids and related biolipids / fatty acids derived from plant or animal oils as the main reaction. The reaction was carried out in a packed-bed continuous-flow reactor (Figure 7). Reactor 700 contains quartz wool 701, support balls 702, catalyst, and support 703. The reactor is designed to operate at up to 550°C and 100 bar, using an electric furnace as heating means. The reactor is equipped with pumps for the feed system and a liquid-gas separator for the product compartment.

[0057] A certain amount (e.g., 3 g) of the Mg-Al-derived LDO-clay composite catalyst (prepared in Example 2) was packed into a reactor tube (inner diameter 10 mm) along with inert support balls or quartz beads to support the catalyst. Carboxylic acids and related biolipids, fatty acids derived from vegetable oils or animal oils (e.g., palmitic acid), were melted and added to the heated feed pump reservoir. The electric furnace was gradually heated to a constant reaction temperature (400 °C), and the nitrogen carrier gas was controlled at an optimal flow rate (e.g., 20 mL / h). The gas outlet valve was opened to release the gas. After the desired conditions were reached and stabilized, the feed pump was turned on at an optimal liquid hourly space velocity (LHSV) (e.g., 3 mL / h flow rate (LHSV = 1 h)). -1 The reactor was operated at 100°C for 1 hour. The liquid product was collected periodically, for example, every hour.

[0058] In one form of the above method, palmitic acid was used as the fatty acid to obtain palmitone as the product.

[0059] Conversion of free fatty acids (FFA) by titration method A portion of the liquid product recovered from the above reaction was dissolved in ethanol. Two drops of phenolphthalein were added to the resulting solution. The solution was then titrated with 0.01 M potassium hydroxide until the color of the solution turned light pink. The conversion rate of the remaining free fatty acids (FFA) was calculated based on the amount of potassium hydroxide required to turn the solution light pink.

[0060] The reaction was stopped when it was complete.

[0061] Results and Discussion In contrast to conventional processes that require a solvent, the process of the present invention involves a solvent-free decarboxylative coupling reaction in which two (or more) molecules of a carboxylic acid react to form a ketone, with carbon dioxide and water as by-products. No dilution of the feedstock is performed before entering the reactor.

[0062] As mentioned above, an example of the method of the present invention was carried out using palmitic acid to produce palmitone. Table 3 shows the yield of palmitone from this decarboxylative coupling reaction. [Table 3]

[0063] Furthermore, the Mg-Al-derived LDO-clay composite catalyst pellets were used to synthesize various types of other fatty acid feedstocks (C 12 ~C 22 ; which may be of biological origin) and have a carbon atom chain length of C 23 ~C 43 A wax (e.g., biowax) of this type is obtained. Furthermore, a dicarboxylic acid having 2 to 11 carbon atoms can also be reacted. In addition to this, or in another embodiment, the fatty acid may be a saturated fatty acid or an unsaturated fatty acid. In addition to this, or in another embodiment, the fatty acid may be a branched-chain fatty acid or a straight-chain fatty acid.

[0064] The composites formed from LDO and clay exhibit unique physicochemical properties that are believed to provide high conversion rates and product selectivities (see Figure 8 and Table 4). [Table 4]

[0065] Furthermore, the catalytic performance of the Mg—Al-derived LDO-clay composite catalyst was tested under harsh conditions for over 500 hours in a continuous-flow packed-bed reactor as described in Example 4 (see FIG. 8).

[0066] The composite catalyst of the present invention, composed of LDO and clay, provides a material with desirable physicochemical properties, robustness, high catalytic activity, and stability. The catalyst exhibits moderate acidity / basicity (at an operating temperature range of 300–500°C), allowing for the adsorption and desorption of feedstocks onto and from active sites. In the presence of CO2, CO2 can bind to strong basic sites and deactivate the catalyst, while weak basic sites can prevent feedstock adsorption. However, a composite catalyst that can avoid these strong or weak basic sites can easily provide the desired catalytic activity without deactivation or reduced reactivity. Furthermore, the composite catalyst disclosed herein exhibits high catalytic activity, demonstrating approximately 99% conversion and over 90% biowax selectivity at a reaction temperature of 400°C and an LHSV of 0.8–1.2. Furthermore, catalytic performance was maintained for over 500 hours without deactivation.

Claims

1. 1. A method for preparing a wax, comprising: (i) providing a feedstock comprising one or more fatty acids having 12 to 22 carbon atoms; and (ii) (a) a layered double oxide; (b) a binder; subjecting said feedstock to a ketonization reaction catalyzed by a composite catalyst material comprising: A method comprising:

2. 10. The process of claim 1, wherein step (ii) is carried out in the absence of a solvent.

3. the one or more fatty acids are selected from monocarboxylic and dicarboxylic acids; The monocarboxylic acid may have 12 to 22 carbon atoms, The dicarboxylic acid may have 2 to 11 carbon atoms.

3. The method according to claim 1 or 2.

4. 4. The method of claim 3, wherein when the one or more fatty acids are monocarboxylic acids only, the wax has one or more components having 23 to 43 carbon atoms, and the wax may be a biowax, and the biowax may have one or more components having 23 to 43 carbon atoms.

5. the layered double oxide is in the form of a plurality of particles uniformly dispersed throughout the composite catalyst material; and / or the layered double oxide is in the form of a plurality of particles uniformly dispersed throughout the composite catalyst material; The method of claim 1.

6. The method of claim 1 , wherein the composite catalyst material is in the form of pellets.

7. the layered double oxide is formed from a combination of a divalent metal cation, a trivalent metal cation, and an oxygen atom; the divalent metal cation is selected from one or more of the group consisting of magnesium, copper, zinc, nickel, and manganese; the trivalent metal cation is selected from one or more of the group consisting of aluminum, iron, and chromium; The layered double oxide may be a magnesium-aluminum layered double oxide. The method of claim 1.

8. The composite catalyst material is (a) 30 to 50 wt. % of the layered double oxide; (b) 50 to 70 wt. % of said binder; The method of claim 1 , comprising:

9. step (ii) is carried out in the absence of a solvent; and / or the binder is a clay, for example, a montmorillonite clay; The method of claim 1.

10. 2. The method of claim 1, wherein step (ii) is carried out at a temperature of from 350 to 450°C, such as from 380 to 420°C, for example at a temperature of about 400°C.

11. 2. The process of claim 1, wherein step (ii) is carried out at a liquid hourly space velocity (LHSV) of 0.8 to 1.

2.

12. 2. The method of claim 1, wherein the feedstock is one or more of a fossil fuel-derived feedstock and a biologically-derived feedstock, and may include a vegetable fatty acid distillate (VFAD) (e.g., palm fatty acid distillate (PFAD)).

13. (a) a layered double oxide; (b) a binder; A composite catalyst material comprising:

14. 14. The composite catalyst material of claim 13, wherein the binder is clay, which may be montmorillonite clay, which may be montmorillonite K30.

15. 15. The composite catalyst material according to claim 13 or 14, wherein the layered double oxide is in the form of a plurality of particles uniformly dispersed throughout the composite catalyst material.

16. 14. The composite catalyst material according to claim 13, wherein said layered double oxide is a magnesium-aluminum layered double oxide.

17. (a) 30-50 wt. % of said composite material; (b) 50 to 70 wt. % of said binder; 14. The composite catalytic material of claim 13, comprising:

18. 14. The composite catalytic material of claim 13 in the form of pellets.

19. 14. A method of forming the composite catalyst material of claim 13, comprising: (a) providing a mixture comprising a layered double oxide, a binder, a plasticizer, a lubricant, and a deflocculating agent; (b) calcining the mixture for a certain period of time to obtain the composite catalyst material. Including, a method.

20. 20. The method of claim 19, wherein the plasticizer is a material containing polar and / or non-polar functional groups, and may be water.

21. 21. The method of claim 19 or 20, wherein the lubricant is a diol.

22. 20. The method of claim 19, wherein the peptizing agent is an acid, which may be an inorganic acid.

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