Solid Catalyst For Manufacturing Fatty Acid Methyl or Ethyl Ester and Method For Manufacturing Fatty Acid Methyl or Ethyl Ester Using the Same

Abstract

The present invention relates to a method for manufacturing a catalyst for synthesizing a fatty acid methyl or ethyl ester and a method for manufacturing a fatty acid methyl or ethyl ester using the catalyst. It provides a method for manufacturing a solid catalyst by mixing the oxides of manganese as active catalytic material and the soda lime glass as carrier wherein the content of the oxides of manganese is in the range of 0.1 w % to 70 w %, molding the mixture to spherical or cylindrical shape and sintering the molded catalyst. It also provides a method for manufacturing fatty acid methyl or ethyl ester with high purity by reacting fatty acid or a mixture of oil and fatty acid with methanol or ethanol by placing the solid catalyst in the reactor.

Claims

1. A solid catalyst with a non-crystalline porous structure that is adapted for converting a fatty acid to fatty acid methyl or ethyl ester, wherein said solid catalyst is prepared by (i) mixing oxides of manganese as active catalytic material and soda lime glass as carrier that consists of SiO.sub.2 as the main component and a mixture comprising NaO, CaO, Al.sub.2O.sub.3, K.sub.2O, SO.sub.3, MgO, Fe.sub.2O.sub.3, and TiO.sub.2, (ii) molding the mixture, and (iii) sintering the molded mixture to produce said solid catalyst having a non-crystalline porous structure, wherein said solid catalysts comprises: 73-76 wt % of SiO.sub.2, 12-15 wt % of NaO, 8-11 wt % of CaO, 2 wt % or less of Al.sub.2O.sub.3, 1 wt % or less of K.sub.2O, 0.5 wt % or less of SO.sub.3, 0.5 wt % or less of MgO, 1 wt % or less of Fe.sub.2O.sub.3, and 0.5 wt % or less of TiO.sub.2.

2. (canceled)

3. The solid catalyst according to claim 1, wherein said the oxides of manganese comprises MnO, MnO2, Mn2O3, Mn3O4, and a mixture thereof.

4. The solid catalyst according to claim 1, wherein the solid catalyst is in a cylindrical shape, or a spherical shape.

5. The solid catalyst according to claim 1, wherein an active catalytic material comprises 0.1 wt % to 70 wt % of the solid catalyst.

6. The solid catalyst according to claim 1, wherein the solid catalyst is sintered in a porous form.

7. A process for manufacturing a solid catalyst according to claim 1, said process comprising the steps of (A) Mixing an adhesion aid, a lubricating aid and a porosity enhancer to maintain the predetermined shape and enhance porosity when a mixture of active catalytic material and carrier is molded; (B) Forming a cylindrical or circular mold, filling the mixed catalyst powder to produce a catalyst through compression; and (C) Sintering the molded catalyst at a temperature of 550 C. to 950 C. for 10-120 minutes to disperse and stabilize the active catalytic material on the carrier.

8. The process for manufacturing a solid catalyst according to claim 7, wherein the adhesive aid includes organic or inorganic adhesives, the lubricating aid includes edible oils, biodiesel, mineral oils, lubricating oils, a porosity enhancer includes all the inert materials for catalyst doping such as cellulose, plastic powder, clay etc. and the method for producing a solid catalyst by using these additives.

9. A process for manufacturing fatty acid methyl or ethyl ester by simultaneously reacting oil and fatty acid with methanol or ethanol, wherein the equivalent ratio of oil and fatty acid to methanol or ethanol is in the range of 1:1 to 1:10, by placing the solid catalyst according to claim 1 inside the reactor, maintaining the temperature inside the reactor at 170 C. to 250 C. and the pressure at 10 bars to 60 bars.

10. The process for manufacturing fatty acid methyl or ethyl ester according to claim 9, wherein the solid catalyst according to claim 1 is placed in a continuous fixed bed reactor, reactants are injected into bottom of the reactor and reacted while being moved upward.

11. The process for manufacturing fatty acid methyl or ethyl ester according to claim 9, wherein the solid catalyst according to claim 1 is placed in a continuous fixed bed reactor, reactants are injected into top of the reactor and reacted while being moved downward to get high yield even with a small amount of methanol by removing glycerin and water, byproducts, rapidly by separating them immediately after the reaction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The above and other objects, features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing in detail exemplary embodiments thereof with reference to the accompanying drawings, in which:

[0045] FIG. 1 is the schematic diagram of a non-continuous reactor for manufacturing fatty acid methyl or ethyl ester according to the present invention.

[0046] FIG. 2 is the schematic diagram of a continuous fixed bed reactor for manufacturing fatty acid methyl or ethyl ester according to the present invention.

[0047] FIG. 3 is the chemical reaction showing esterification to manufacture fatty acid methyl or ethyl ester according to the present invention.

[0048] FIG. 4 is the chemical reaction showing transesterification to manufacture fatty acid methyl or ethyl ester according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0049] Hereinafter, examples of the present invention will be described in detail.

[0050] In describing the present invention, a detailed description of well-known functions or constructions will be omitted for clarity of the present invention. In addition, even if the kind of the at least one minor amount of the soda lime glass is changed or the content thereof is slightly different, the catalytic action and the physical properties such as the compressive strength of the solid catalyst finally produced are hardly affected. In order to clarify the structure and operation effects of the soda lime glass according to the present invention, the metal oxide components constituting the soda lime glass will not be listed in the examples of the present invention.

[0051] First, a method for manufacturing a ceramic metal catalyst according to the present invention will be described in detail.

Example 1: Preparation of a Solid Catalyst for the Synthesis of Fatty Acid Methyl or Ethyl Ester from Oil Containing Fatty Acid

[0052] Solid catalysts are prepared by varying the ratio of the carrier material, soda lime glass, and manganese dioxide, which is an active catalytic material. As shown in Table 1, the mixing ratio of the carrier material and the active catalytic material was varied, and a small amount of the adhesion aid, the lubricating aid, and the porosity enhancer were uniformly mixed.

[0053] A cylindrical mold having a diameter of 8 mm and a length of 12 mm is filled with a catalyst mixture and molded into a cylindrical shape under pressure. Cylindrical catalysts were sintered at 750 C. for 40 minutes to prepare solid catalysts. The results were as follows.

TABLE-US-00001 TABLE 1 Diameter Exam- Catalyst of the Compressive ple Carrier material catalyst strength 1-1 Soda lime glass 90 g MnO.sub.2 10 g 8 mm 115 kg/cm2 1-2 Soda lime glass 60 g MnO.sub.2 40 g 8 mm 83 kg/cm2 1-3 Soda lime glass 30 g MnO.sub.2 70 g 8 mm 39 kg/cm2

[0054] As shown in Table 1, when the weight ratio of the active catalytic material is increased, the reaction yield shown in Table 4 is high. However, the solid catalyst having 70 wt % of the active material has a remarkably low compressive strength and is expected to be broken. The active catalytic material is thus controlled not to exceed 70 wt % of the solid catalyst.

Example 2: Preparation of a Solid Catalyst for the Synthesis of Fatty Acid Methyl or Ethyl Ester from Oil Containing Fatty Acid

[0055] Solid catalysts were prepared by sintering the molded catalyst composed of 60 wt % of soda lime glass as a carrier material and 40 wt % of manganese dioxide as an active catalytic material at different temperatures. As shown in Table 2, the mixing weight ratio of the carrier material and the active catalytic material was uniformly mixed, and a small amount of the adhesion aid and the lubricating aid, and the porosity enhancer were uniformly mixed.

[0056] A cylindrical mold having a diameter of 8 mm and a length of 12 mm is filled with a catalyst mixture and molded into a cylindrical shape under pressure. The catalysts prepared in cylindrical form were sintered at 550 C.-950 C. for 40 min to prepare solid catalysts. The results were as follows.

TABLE-US-00002 TABLE 2 2-1 Soda lime glass 60 g MnO.sub.2 40 g 8 mm 550 C. 6 kg/cm2 2-2 Soda lime glass 60 g MnO.sub.2 40 g 8 mm 650 C. 63 kg/cm2 2-3 Soda lime glass 60 g MnO.sub.2 40 g 8 mm 750 C. 90 kg/cm2 2-4 Soda lime glass 60 g MnO.sub.2 40 g 8 mm 850 C. 127 kg/cm2 2-5 Soda lime glass 60 g MnO.sub.2 40 g 8 mm 950 C. 162 kg/cm2

[0057] As can be seen from Table 2, when the sintering temperature was 550 C., a catalyst having a very low hardness was obtained and was not suitable for use. From 650 C., solid catalysts with good hardness were obtained. Solid catalysts which can be used sufficiently for the synthesis of fatty acid methyl ester or ethyl ester were obtained.

Example 3: Preparation of a Solid Catalyst for the Synthesis of Fatty Acid Methyl or Ethyl Ester from Oil Containing Fatty Acid

[0058] Solid catalysts were prepared by sintering the molded catalyst composed of 60 wt % of soda lime glass as a carrier material and 40 wt % of manganese dioxide as an active catalyst material at 750 C. for various sintering time. As shown in Table 3, the mixing weight ratio of the carrier material and the active catalytic material was uniformly mixed, and a small amount of the adhesion aid and the lubricating aid, and the porosity enhancer were uniformly mixed.

[0059] A cylindrical mold having a diameter of 8 mm and a length of 12 mm is filled with a catalyst mixture and molded into a cylindrical shape under pressure. Cylindrical catalysts were sintered at 750 C. for 10120 minutes to produce solid catalysts.

TABLE-US-00003 TABLE 3 3-1 Soda lime glass 60 g MnO.sub.2 40 g 8 mm 10 min 23 kg/cm2 3-2 Soda lime glass 60 g MnO.sub.2 40 g 8 mm 20 min 63 kg/cm2 3-3 Soda lime glass 60 g MnO.sub.2 40 g 8 mm 30 min 84 kg/cm2 3-4 Soda lime glass 60 g MnO.sub.2 40 g 8 mm 40 min 92 kg/cm2 3-5 Soda lime glass 60 g MnO.sub.2 40 g 8 mm 60 min 102 kg/cm2 3-6 Soda lime glass 60 g MnO.sub.2 40 g 8 mm 120 min 107 kg/cm2

[0060] As can be seen from Table 3, it was confirmed that the sintering time of 10 minutes was somewhat insufficient at 750 C. After a sintering time of 20 minutes, Solid catalysts with good strength were obtained. They can be used sufficiently for the synthesis of fatty acid methyl or ethyl ester.

Example 4: Synthesis of a Fatty Acid Methyl Ester from Oil Containing Fatty Acid

[0061] A fatty acid methyl ester was synthesized by adding oil containing fatty acid and methanol using the capped reactor (1) having a capacity of 250 ml shown in FIG. 1. A porous box (2) which can be filled with catalyst is installed on the shaft of the stirrer provided at the center of the reactor, and the solid catalyst (3) is filled therein, and then rotated by the motor (4). At the start of the reaction, the cab of the reactor was opened first, and 20 g of the solid catalyst prepared in Example 1, Example 2 and Example 3 was exchanged and installed in the porous box (2) each time the reaction was carried out. 100 g of the waste cooking oil containing 30% of fatty acid and 30 g of methanol are filled, the lid is closed, and the motor (4) is rotated to mix the reactants. The temperature inside the reactor is heated to 200 C. by a temperature controller (5) to control the temperature inside. When the internal temperature reached 200 C., the reaction was continued at the same temperature for 2 hours. It was confirmed that the reaction pressure was 24-32 bars by the pressure gauge (6). After the completion of the reaction, the reactor is cooled by passing the cooling water through the temperature controller and the cap is opened to take the sample from hydrophobic phase and the methanol component was removed from the sample. The concentration of the fatty acid methyl ester in the reaction product is analyzed by gas chromatography to calculate the product purity and the acid value was measured by acid-base titration. The results are as follows.

TABLE-US-00004 TABLE 4 Content of fatty Exam- acid methyl ester Acid ple Catalyst used (wt %) value 4-1 Example 1, 1-1 catalyst 83.5 9.6 4-2 Example 1, 1-2 catalyst 91.9 7.2 4-3 Example 1, 1-3 catalyst 93.3 6.5 4-4 Example 2, 2-2 catalyst 92.8 5.8 4-5 Example 2, 2-3 catalyst 93.1 6.1 4-6 Example 2, 2-4 catalyst 82.6 7.4 4-7 Example 2, 2-5 catalyst 65.9 9.9 4-8 Example 3, 3-1 catalyst 92.2 5.3 4-9 Example 3, 3-2 catalyst 93.4 5.1 4-10 Example 3, 3-3 catalyst 91.8 6.7 4-11 Example 3, 3-4 catalyst 93.5 6.3 4-12 Example 3, 3-5 catalyst 90.4 6.4 4-13 Example 3, 3-6 catalyst 90.1 7.1

[0062] Table 4 shows the results of carrying out the reaction using the solid catalysts prepared in Examples 1 to 3. Fatty acid methyl esters with high purity of 90% or more were able to be produced even when the methanol content was 30% of oil. However, it was confirmed that when the active catalytic material is used in a small amount of 10% and when the sintering temperature of the solid catalyst is more than 850 C., the yield is drastically reduced.

[0063] On the other hand, an advantage that the process is simplified can be obtained since the used solid catalyst is fixed in the solid state without breakage in the reactor, the catalyst is not contained in the fatty acid methyl ester after the reaction and thus the step of separating the catalyst from the reaction product is not necessary.

Example 5: Synthesis of a Fatty Acid Ethyl Ester from Oil Containing Fatty Acid

[0064] A fatty acid ethyl ester was synthesized by adding oil containing fatty acid and ethanol using the capped reactor (1) having a capacity of 250 ml shown in FIG. 1. A porous box (2) which can be filled with catalyst is installed on the shaft of the stirrer provided at the center of the reactor, and the solid catalyst (3) is filled therein, and then rotated by the motor (4). At the start of the reaction, the cap of the reactor was opened first, and 20 g of the solid catalyst prepared in Example 1 was installed in the porous box (2) to carry out the reaction. 100 g of the waste cooking oil containing 30% of fatty acid and 40 g of anhydrous ethanol are filled, the lid is closed, and the motor (4) is rotated to mix the reactants. The temperature inside the reactor is heated to 200 C. by a temperature controller (5) to control the temperature inside. When the internal temperature reached 200 C., the reaction was continued at the same temperature for 2 hours. It was confirmed that the reaction pressure was 25 bars by the pressure gauge (6). After the completion of the reaction, the reactor is cooled by passing the cooling water through the temperature controller and the cap is opened to take the sample from hydrophobic phase and the ethanol component was removed from the sample. The concentration of the fatty acid ethyl ester in the reaction product is analyzed by gas chromatography to calculate the product purity and the acid value was measured by acid-base titration. The results are as follows.

TABLE-US-00005 TABLE 5 Content of fatty Exam- acid methyl ester Acid ple Catalyst used (wt %) value 5-1 Example 1, 1-2 catalyst 92.3 6.8

[0065] Table 5 shows that when the reaction was carried out using the 1-2 solid catalyst prepared in Example 1, fatty acid ethyl ester with high purity of 92.3% was able to be produced when the ethanol content was 40% of oil.

Example 5: Synthesis of a Fatty Acid Methyl Ester from Oil Containing Fatty Acid

[0066] Fatty acid methyl ester was synthesized by adding oil containing fatty acid and methanol using the continuous fixed bed reactor shown in FIG. 2.

[0067] 350 kg of the 1-2 catalyst (7) of Example 1 is filled in the continuous fixed-bed reactor having an inner capacity of 300 liters (8) and the lid is closed. Palm oil containing 30% of fatty acid is prepared in the raw material oil container (9) having a capacity of 2,000 liters equipped with a stirrer, and methanol is prepared in the methanol container having a capacity of 500 liters (10). Palm oil containing fatty acid and methanol are supplied at the speed of 100 kg per hour by the metering pump (11) and 15-30 kg per hour by the metering pump (12), respectively. The temperature of the reaction mixture is controlled to 200 C. by a heat exchanger (13). Internal temperature of the reactor is maintained by the hot oil boiler system (14). The residence time of the reactants is 1 hour, and the reactants discharged continuously from the reactor are collected in the vessel (16) collecting the reaction products after passing through the pressure regulating valve (15). The evaporated methanol is sent to the methanol refining process. The direction to inject the reactant into the reactor can be both top and bottom, and when it is injected from the top, the glycerin produced as a byproduct in the reaction is easily discharged. An example of this was proceeded. Particularly, when glycerin and water whose specific gravity are higher than that of fatty acid methyl ester are separated from the hydrophobic component, they are rapidly transported to the lower part of the reactor. Since water and glycerin are removed from the solid catalyst in contact with the lipophilic group because the oil is rapidly transported to the lower part of the reactor, advantage of promoting the forward reaction shown in Reaction 1 and 2 of FIGS. 3 and 4 arises. Therefore, the present invention can increase the fatty acid methyl ester content by lowering methanol content in the reactants.

[0068] Methanol was removed from the reaction product, the concentration of the fatty acid methyl ester in the reaction product is analyzed by gas chromatography to calculate the product purity and the acid value was measured by acid-base titration. The results are as follows.

TABLE-US-00006 TABLE 6 Methanol Content of content to fatty acid Exam- Catalyst the oil methyl ester Acid ple used (wt %) (wt %) value 6-1 Example 1, 1-2 catalyst 15 92.5 6.8 6-2 Example 1, 1-2 catalyst 20 93.1 7.1 6-3 Example 1, 1-2 catalyst 25 92.8 6.4 6-4 Example 1, 1-2 catalyst 30 92.9 6.3

[0069] The solid catalyst of the present invention is very effective for a continuous fixed-bed reactor and shows a very high yield of 90% or more even though the content of methanol is low. Furthermore, even if a low cost raw material containing a large amount of fatty acid is used, no soap or a catalyst component does not contaminate the reaction product, and it is possible to simultaneously secure high value addition of waste, prevention of environmental pollution and high economic efficiency.

[0070] According to the above-described present invention, the following effects can be expected.

[0071] As described above, the present invention provides the advanced concept solid catalyst which is the soda lime glass on which the oxide of manganese doped. The carrier was mixed with 0.1-70 w % of active catalytic materials composed of at least one oxide of manganese and then sintered together to have very high hardness.

[0072] The present invention also provides method of manufacturing high purity fatty acid methyl or ethyl ester with the maximum yield by fixing the solid catalyst inside of the reactor to react oil and fatty acid with methanol or ethanol simultaneously. It does not need the process to remove and refine catalysts.