USE OF HETEROGENEOUS ACID CATALYSTS BASED ON MIXED METAL SALTS TO PRODUCE BIODIESEL

Abstract

The present invention relates to the production of biodiesel and alkyl esters by the transesterification of triglyceride esters, with alcohols in heterogeneous phase in the presence of heterogeneous catalysts, with yields higher than 80%, at a temperature from 0 to 300° C., residence time from 20 minutes to 20 h, space velocity of 0.1 to 10 h.sup.−1, pressure of 25-100 kg/cm.sup.2 (24.5-98.07 bar), methanol/oil molar ratio of 10 to 40 and catalyst concentration of 0.001 to 20 weight % based on tri-, di- or monoglyceride. The method produces biodiesel and alkyl esters by transesterification of tri-, di- or mono-glycerides, from palm, jatropha, castor, soybean and sunflower oils, wherein the alcohoxyls R.sup.1O, R.sup.2O and R.sup.3O of the glycerides are C.sub.1 to C.sub.24 and a C.sub.1-C.sub.4 alcohol, such as methanol, in an alcohol:oil ratio from 3:1 to 50:1. The transesterification reaction produces biodiesel while avoiding loss of catalyst, contaminating liquid effluents and eliminating undesirable hydrolysis of triglycerides, diglycerides and monoglycerides into free fatty acids and saponification that generate soaps.

Claims

1. A method of producing biodiesel by the transesterification of triglyceride esters with alcohols in the presence of a heterogeneous acid catalyst primarily Lewis acid in nature in heterogeneous phase, in reaction systems, batch or continuous flow, in descending or ascending mode, to obtain yields exceeding 80%, at the following operating conditions: temperature from 150 to 300° C., residence time from 20 minutes to 20 h, space velocity from 0.1 to 10 h.sup.−1, pressure 25-100 kg/cm.sup.2 (24.5-98.07 bar), alcohol/oil molar ratio of 10 to 40 and catalyst concentration of 0.001 to weight % based on tri-, di- or monoglyceride.

2. The method of producing biodiesel according to claim 1, wherein the heterogeneous acid catalysts are composed of mixed metal salts of lithium and aluminum phosphates and sulfates with the following percentages of metals in weight of the catalyst lithium up to 5 weight %, and aluminum up to 15%, in addition to their combinations with metal cations in concentrations of up to 40 weight % of the catalyst, where the metal cations are selected from the group consisting of magnesium, titanium, zinc, zirconium, gallium and silicon, to provide adequate Lewis acidity type; organic or Inorganic porosity promoters in concentrations of from 0.05 to 25 weight % of the wet base catalyst, and binders in concentrations of 1 to 20 weight % of the catalyst, selected from the group consisting of clays, kaolin and metal oxides of the formula M.sub.xO.sub.y, where M=Al, Mg, Sr, Zr or Ti, X=1 or 2 and y=2 or 3, for the formation of particles of shape and size established, such as extrudates, spheres, trilobules and raschig rings.

3. The method of producing biodiesel according to claim 2, wherein the mixed metal salts of the catalyst, in addition to their combinations with metal cations, are selected from the group consisting of: a. Phosphates and sulfates of lithium and aluminum, b. Lithium, aluminum and titanium phosphates and sulfates, and c. Phosphates and sulfates of lithium, aluminum and magnesium.

4. The method of producing biodiesel according to claim 2, wherein the polysaccharide employed in the catalyst as the porosity promoter is amylose-amylopectin (starch).

5. The method of producing biodiesel, according to claim 2, wherein the clays as binders are of the montmorillonite type.

6. The method of producing biodiesel according to claim 2, wherein the catalyst has a surface area of 10 to 180 m.sup.2/g, pore volume from 0.1 to 0.5 cm.sup.3/g, and average pore diameter from 100 to 200 Å.

7. The method of producing biodiesel according to claim 1, wherein the transesterification of triglyceride esters with alcohols in a heterogeneous phase is carried out using vegetable oils selected from the group consisting of palm oil, jatropha, castor, soybean and sunflower, and a C.sub.1-C.sub.4 alcohol in an alcohol:oil ratio of 3:1 to 50:1

8. The method of producing biodiesel according to claim 1, wherein the transesterification of triglyceride esters with alcohols in heterogeneous phase in batch reaction systems is carried out in stirred tank with residence times from 20 minutes to 20 h.

9. The method of producing biodiesel according to claim 1, wherein the transesterification of triglyceride esters with alcohols in a heterogeneous phase in continuous flow reaction systems is carried out in a packed reactor flow rate in descending or ascending mode, at a space velocity of 0.1 to 10 h.sup.−1, a pressure of to 100 kg/cm.sup.2, a temperature of 150 to 300° C. and a methanol/oil molar ratio of 10 to 40.

10. The method of producing biodiesel, according to claim 1, wherein the transesterification of triglyceride esters with heterogeneous phase alcohols in continuous, ascending or descending flow is carried out in combination with other catalytic materials of a basic nature selected from the group consisting of magnesium oxides, aluminum oxides and sodium oxides to simultaneously promote the esterification and transesterification reactions.

11. The method of producing biodiesel according to claim 1, wherein the transesterification of triglyceride esters with alcohols in heterogeneous phase in batch reaction systems is performed in stirred tank with residence times of 20 minutes to 20 h.

12. The method of producing biodiesel according to claim 1, wherein the transesterification of triglyceride esters with heterogeneous phase alcohols is carried out in a continuous flow reactor in a descending or ascending manner at a space velocity of 0.1 to 10 h.sup.−1, a pressure of 25 to 100 kg/cm.sup.2, a temperature of 150 to 300° C. and a molar ratio of methanol/Oil from 10 to 40.

13. The method of claim 2, wherein said catalyst includes 0.1 to 3 weight % lithium and 0.3 to 10 weight % aluminum.

14. The method of claim 2, wherein said metal cation is selected from the group consisting of titanium, magnesium and silicon and where said metal cation is present in an amount of 0.2 to 30 weight % based on the weight of the catalyst.

15. The method of claim 2, wherein said porosity promoter is a polysaccharide.

16. The method of claim 2, wherein said binder is a clay in the amount of 3 to 15% weight %.

17. The method of claim 2, wherein the catalyst has a surface area of 30 to 80 m.sup.2/g, a pore volume of 0.1 to 0.3 cm.sup.3/g, and an average pore diameter of 110 to 170 Å.

Description

BRIEF DESCRIPTION OF THE DRAWINGS OF THE INVENTION

[0052] FIG. 1 shows the classification of acid catalysts according to Brönsted acid sites by having interactions of carbonyl oxygen with proton (H.sup.+) sites on the catalyst and those with Lewis acid sites due to interactions of carbonyl oxygen with the cationic sites (M.sup.+).

[0053] FIG. 2 is a flow chart for the preparation of heterogeneous acid catalysts based on mixed metal salts, preferred by the present invention to produce biodlesel, HLPA, HLPAT and HLPAM series, respectively; and also applicable to HLSAT and HLSAM series with any precursor source of S and Ti.

[0054] FIG. 3 is a graph showing the Lewis acidity sites of the heterogeneous acid catalysts based on mixed metal salts, preferred by the present invention to produce biodiesel, HLPA, HLPAT and HLPAM series, determined by Fourier Transform Infrared Spectrometry (FTIR).

[0055] FIG. 4 is a batch reactor scheme for evaluating heterogeneous acid catalysts primarily Lewis in nature to produce biodlesel by transesterification of triglyceride esters with alcohols in a heterogeneous phase.

[0056] FIG. 5 shows a continuous flow reactor scheme for evaluating heterogeneous acid catalysts primarily Lewis in nature to produce biodlesel by transesterification of triglyceride esters with alcohols in a heterogeneous phase.

DETAILED DESCRIPTION OF THE INVENTION

[0057] The present invention relates to the use of heterogeneous acid catalysts primarily Lewis in nature in a method for producing biodiesel by the transesterification of mono-, di- and/or triglyceride esters, preferably by the transesterification of fresh or wasted vegetable oils, or oils and fats of animal origin, with alcohols in heterogeneous phase, in batch or continuous flow systems, in ascending or descending mode, with yields higher than 80%, at the following operating conditions: temperature from 150 to 300° C., residence time from 20 minutes to 20 h, velocity space from 0.1 to 10 h.sup.−1, pressure of 25-100 kg/cm.sup.2 (24.5-98.07 bar), methanol/oil molar ratio of 10 to 40 and catalyst concentration of 0.001 to 20 weight % based on tri-, di- or monoglyceride.

[0058] More specifically, the use of heterogeneous acid catalysts primarily Lewis in nature in a method of producing biodiesel by the preparation of alkyl esters of alkyl by transesterification of tri-, di- or mono-glycerides, such as those derived from oils of vegetable or animal origin, in particular palm, jatropha, castor, soybean and sunflower oils, where the R groups of the alcohoxyls R.sup.1O, R.sup.2O and R.sup.3O of the glycerides are from C.sub.1 to C.sub.24 and a C.sub.1-C.sub.4 alcohol such as methanol, in an alcohol:oil ratio of 3:1 to 50:1.

[0059] In this respect, it is important to note that the transesterification of triglyceride esters with alcohols in a heterogeneous phase is preferably carried out: [0060] In stirred tank with residence times of 20 minutes to 20 h for batch reaction systems, and [0061] in a continuous flow reactor, in ascending or descending mode, at a space velocity of 0.1 to 10 h.sup.−1, pressure of 25 to 100 kg/cm.sup.2, temperature of 150 to 300° C. and a methanol/oil molar ratio from 10 to 40, for continuous flow reaction systems.

[0062] On the other hand, a primary reason to carry out the heterogeneous phase transesterification reaction to produce biodiesel is to avoid contaminating liquid effluents and to avoid undesirable parallel reactions such as the hydrolysis of triglycerides, diglycerides and monoglycerides into free fatty acids, in addition to that in the case of catalysts of a basic nature, the saponification could generate soaps.

[0063] FIG. 2 shows in general a scheme for the preparation of heterogeneous acid catalysts based on mixed metal salts, preferred by the present invention to produce biodiesel, HLPA, HLPAT and HLPAM series, respectively; and additionally, applicable to HLSAT and HLSAM series with any precursor source of S and Ti.

[0064] In this regard, FIG. 3 shows a graph of the Lewis acidity sites of heterogeneous acid catalysts based on mixed metal salts, preferred by the present invention to produce biodiesel, HLPA, HLPAT and HLPAM series, respectively, determined by Fourier Transform Infrared Spectrometry (FTIR).

[0065] Lithium and aluminum phosphates and sulfates have not been considered so far, in addition to their combinations with metallic cations such as magnesium, titanium, zinc, zirconium and gallium, as heterogeneous phase acid catalysts with a primarily Lewis nature in the transesterification reaction of triglyceride esters in heterogeneous phase to produce biodiesel, in both batch reaction systems and in continuous flow reaction systems, In ascending or descending mode, with yields higher than 80%. In one embodiment, the lithium and aluminum phosphates and/or sulfates catalyst further includes a basic catalytic material, such as magnesium oxide, aluminum oxide and sodium oxide to promote the esterification and transesterification reaction.

[0066] The heterogeneous acid catalysts primarily Lewis nature employed by the present invention for producing biodiesel are preferably composed of mixed metal salts, such as lithium and aluminum phosphates and sulfates, with the following percentages of metals by weight of the catalyst: lithium of up to 5 weight % and generally 0 to 5 weight %, preferably 0.1 to 3 weight %, and aluminum up to 15 weight % and generally from 0 to 15 weight %, preferably 0.3 to 10 weight %; in addition to combinations of the lithium and aluminum phosphates and/or sulfates with metal cations in concentrations of 0 to 40 weight % of the catalyst, such as magnesium, titanium, zinc, zirconium, gallium and silicon, preferably titanium, magnesium and silicon, in concentrations of 0.2 to 30 weight %, which provide adequate Lewis acidity; organic or inorganic porosity promoters in concentrations of from 0.05 to 25% by weight of the wet base catalyst, preferably up to 12 weight % and generally from 0 to 12 weight %, such as polysaccharides; and binders in concentrations of 1 to 20 weight % of the catalyst, such as clays, kaolin and metal oxides of the type MxOy, where M=Al, Mg, Sr, Zr or TI, among other metals of groups IA, IIA and IVB, X=1 or 2 and y=2 or 3, preferably clays in concentrations of 3 to 15 weight %, for the formation of particles with geometry and size, such as extrudates, spheres, trilobes and raschig rings, among others; having the following properties: surface area of 10 to 180 m.sup.2/g, preferably 30 to 80 m.sup.2/g, pore volume of 0.1 to 0.5 cm.sup.3/g, preferably 0.1 to 0.3 cm.sup.3/g, and average pore diameter 100 to 200 Å, preferably 110 to 170 Å. The lithium and aluminum phosphate and sulfate catalyst can be prepared by the method disclosed in commonly owned MX/a/2016/004132 and its corresponding US patent application filed concurrently herewith, which is hereby incorporated by reference in its entirety. [0067] The mixed metal salts in addition to their combinations with metallic cations are preferably: [0068] Lithium and aluminum phosphates and sulfates (HLPA and HLSA Series, respectively), [0069] Lithium, aluminum and titanium phosphates and sulfates (HLPAT and HLSAT series respectively), and [0070] Phosphates and sulfates of lithium, aluminum and magnesium (HLPAM and HLSAM Series respectively). [0071] the polysaccharide used as a porosity promoter is preferably amylose-amylopectin (starch). [0072] the clays used as binders are preferably of the montmorillonite type.

[0073] The evaluation of the heterogeneous acid catalysts primarily Lewis acids to produce biodiesel by the transesterification of fresh or wasted vegetable oils or oils and fats of animal origin was carried out in a batch bank reactor with a capacity of 300 ml of the Parr brand, as well as in a packed bed reactor and continuous flow. The experiments allowed to select the operating conditions to evaluate the catalytic materials in development Temperature=200° C., P=40 kg/cm.sup.2, MeOH/Oil mole ratio=18 and residence time of 6-24 h, and for the packed reactor at temperatures of 150-300° C., P=25-100 kg/cm.sup.2, mol ratio MeOH/Oil=10-40 and space velocity from 0.1 to 5 h.sup.−1.

[0074] Similarly, combinations of the acid catalyst with a basic catalyst based on metal oxides were evaluated to carry out the transesterification of the feed, primarily, by reducing its free fatty acid content with the acid catalyst and subsequently with the catalyst alkaline nature, produce biodiesel in batch reaction systems or continuous flow in ascending or descending mode.

EXAMPLES

[0075] Some practical examples of the present invention will now be described, for a better understanding thereof, without limiting its scope.

[0076] The evaluation of heterogeneous acid catalysts primarily Lewis acids to produce biodiesel by transesterification of triglyceride esters with alcohols in a heterogeneous phase was carried out using a refined, bleached and deodorized (RBD) palm oil with the properties presented in Table 1, which was subjected to transesterification in both batch reactor (Examples 1 and 2), and in continuous flow reactor (Examples 3 to 12), with a light or lower alcohol having the properties shown in Table 2; obtaining a transesterified product containing fatty acid methyl esters (FAME).

TABLE-US-00001 TABLE 1 Properties of RBD palm oil, used as a feed in the Examples of the present invention. Properties Units Values Density @ 50° C. 0.888-0.889 Kinematic viscosity @ 40° C. cSt (mm.sup.2/s) 1.9-6.0 Acid number mgKOH/g 0.5-0.8 Iodine Index 46-56 Fatty acid % peso C-12:0 Lauric 0.1-1.0 C-14:0 Myristic 0.9-1.5 C-16:0 Palmitic 41.8-46.8 C-16:1 Pelmitoleic 0.1-0.3 C-18:0 Stearic 4.5-5.1 C-18:1 Oleic 37.3-40.8 C-18:2 Linoleic  9.1-11.0 C-18:3 Linolenic 0.4-0.6 C-20:0 Arachidic 0.2-0.7 Diglyceride % peso 3.0-7.6

TABLE-US-00002 TABLE 2 Properties of methanol used as feed, in the Examples of the present invention. Specification Unit Values Distillation at 780 mmHg ° C. 1.0% max. Includes 64.6 Purity Wt % 99.85-99.99 Color Pt—Co 5 máx. Acidity (acetic acid) Wt % 0.003 máx. Permanganate test Minutes 50 min Acetone Wt % 0.003 máx. Water Wt % 0.10 máx. Non-volatile matter Wt % 0.001 máx. Carbonisable Substances Pt—Co 50 máx. Specific Gravity 20/20° C. — 0.7920-0.7932

Example 1

[0077] Evaluation in Batch Reactor with Refined, Bleached and Deodorized Palm Oil (RBD)

[0078] These tests were performed in a system as shown in Figure No. 4, where:

[0079] M=methanol,

[0080] O=oil,

[0081] C=catalyst,

[0082] M NR=unreacted methanol,

[0083] P=products,

[0084] BD=biodiesel,

[0085] G=glycerol, and

[0086] O NR=unreacted oil. [0087] 1. Six 5 mL vials, each with 1/6 of the total weight of the catalyst to be evaluated (5% oil base) were prepared as described in Table No. 3, with particle size equivalent to mesh numbers 30 and 40; and six 50 mL wide mouth flasks, each with 1/6 of the total diluent (SIC) weight and 30-40 mesh particle size. The weight of the empty basket of the catalyst and of the empty vessel of the Parr reactor were recorded. [0088] 2. The contents of a 5 mL glass vial were mixed with the catalyst contained in one of the 50 mL wide-mouth flask containing the diluent (SiC), this was repeated for the remaining 5 vials and 5 flask, and each flask was mixed to obtain an homogeneous solid mixture. [0089] 3. Each section of the catalyst basket was charged with 2 of the flask of the diluent and catalyst mixture, taking care of the preservation of the catalyst-diluent mixture. The weight of the basket loaded with the catalyst and diluent mixture was recorded. [0090] 4. The catalyst basket was introduced into the reactor. The oil and methanol feeds were weighed, then poured into the Parr reactor vessel. The reactor was immediately sealed and fed with N.sub.2 to an initial pressure of 7 kg/cm.sup.2; upon reaching this pressure the N.sub.2 feed was suspended. The cooling water pass valve was opened 1/8 turn. [0091] 5. The Parr reactor software was programmed to take the heating to 200° C. and the reactor controller was set at a stirring speed of about 750 rpm. The heating level II (high power) was maintained until reaching 100° C. and then switched to the heating level I (low power). The heating log was updated every 5 min. According to the heating of 100 to 200° C. continuously, the cooling water pressure of the stirrer was monitored to maintain constant flow and prevent the temperature from falling due to a high water flow or the agitator section being heated due to a decrease in water flow. [0092] 6. The start of the reaction was considered when the reactor reached 200° C. and 40 kg/cm.sup.2 and recording of the pressure, temperature, stirring rate and heating percentage was performed every 15 min for 6 hours. [0093] 7. After 6 h of reaction at 200° C. and 40 kg/cm.sup.2, heating was stopped in the reactor controller and the gradual cooling of the reactor was started until the initial temperature and a pressure of 7 kg/cm.sup.2 were reached. [0094] 8. The reactor was opened and the obtained oily product was deposited in a 253-mL pre-tared wide-mouth clear Flask. The weight of the flask was recorded with the oily product. The weight of the reactor containing the basket was recorded with the wet catalyst. The reactor was closed with the wet basket and N.sub.2 was fed to a pressure of 7 kg/cm.sup.2, the reactor was left standing for the next experiment. [0095] 9. The oily product was centrifuged using an IEC CU-5000 centrifuge at 1,500 rpm for 10 min, according to the procedure established for the transesterification products. The obtained phases were separated in the centrifugation and the weight and volume of these were registered to realize the mass balance. The phase separation was performed with Pasteur pipettes, initiating the pipetting of the sample from the lower phase. In addition, the color and appearance of the phases were recorded and a sample of the phase was taken. [0096] 10. The biodiesel phase was then subjected to simple distillation to remove excess methanol, starting at 65° C. and ending at 100-120° C. A biodlesel sample was taken for analysis by gas chromatography and mass spectrometry (GC-MS) and to analyze the composition of FAME and total content of these. [0097] 11. At the end of the experiment, the diluent and catalyst were discharged from the basket. In a Soxhlet kit with chloroform at 50° C. and constant atmospheric pressure, the catalyst and the diluent were cleaned. After cleaning the catalyst and the diluent were deposited in a 120 mL amber flask with wide mouth and thread.

[0098] The catalysts prepared and evaluated in the batch reactor showed FAME yield values determined by Nuclear Magnetic Resonance (NMR) from 82 to 90.7 weight %.

[0099] Table 3 shows the evaluated catalysts and their behavior in terms of biodiesel yield and FAME content, emphasizing the effect of the Metal/P (M/P) ratio for mixed metal salts and their combinations with Metal cations prepared with lithium, aluminum, titanium and magnesium according to the used series, and starch added as a porosity promoter. Likewise, the surface area determined by the BET method is shown

TABLE-US-00003 TABLE 3 Behavior of heterogeneous acid catalysts in a batch reactor with RBD palm oil based on their Metal/P ratio.sup.(1), starch content and surface area. Surface % Starch area Yield.sup.(2) % Content Catalyst Li/P Al/P M/P (g) (m.sup.2/g) (RMN) of FAME HLPA-6 1.17 4.57 10.9 170.40 88.67 89.7 HLPA-16 1.20 4.65 3.7 137.05 89.67 91.3 HLPA-20 0.08 0.32 4.7 20.87 82.00 89.3 HLPAT-1 0.02 0.06 Ti/P 0.0 94.77 85.33 91.8 0.05 HLPAM-3 1.19 4.63 Mg/P 4.7 52.08 90.70 93.4 2.08 .sup.(1)Wet base; .sup.(2)Yield

Example 2

[0100] The palm oil RBD, having the properties presented in Table 1, was subjected to the step of transesterification with methanol, with the properties shown in Table 2, using the heterogeneous catalyst HLSA-4 whose composition is Al—Li—S at concentrations of 1 wt % Li, 3.9 wt % Al and 10.8 wt % S on a dry basis. The transesterification reaction was carried out in a batch reactor with 5% base catalyst to the oil, under the operating conditions shown in Table 4.

TABLE-US-00004 TABLE 4 Operating conditions of the catalytic transesterification step of the RBD palm oil of Example 2. Variable Condition Pressure, kg/cm.sup.2 40 Temperature, ° C. 200 Reaction time, h 6 Mole ratio MeOH/Oil 18

[0101] The transesterified product was obtained with a biodiesel yield of 71.7 wt % with a FAME content of 65.1 wt %

Example 3

[0102] An evaluation with a heterogeneous acid catalyst of primarily Lewis nature, in composition Al—P—Zr, with concentrations of 20 weight % of P.sub.2O.sub.5, 24 weight % of ZrO.sub.2, and 56 weight % of Al.sub.2O.sub.3, was carried out in equal parts, with a catalyst having an alkaline nature, containing Mg:Al in a weight ratio of 1.1:1, to produce biodiesel by transesterification of triglyceride esters with alcohols in a heterogeneous phase, using as feed an animal fat with basic density properties of 0.9160 g/mL measured at 20° C., kinematic viscosity at 37.8° C. of 42.3 cSt (mm.sup.2/s), acid value of 5.04 mg KOH/g, moisture of 0.5 weight % and Impurities content of 0.5 weight %.

[0103] The animal fat was subjected to the step of transesterification with methanol, with the properties shown in Table 2, using the heterogeneous acid catalyst in combination with the alkaline catalyst. The transesterification reaction was carried out in a batch reactor at the operating conditions shown in Table 5 to give a transesterified product containing methyl esters of fatty acids (FAME).

TABLE-US-00005 TABLE 5 Operating conditions of the catalytic transesterification step of animal fat, from Example 3. Variable Condition Pressure, kg/cm.sup.2 40 Temperature, ° C. 200 Reaction time, h 3 Mole ratio MeOH/Oil 18

[0104] The transesterified product was obtained with a biodiesel yield of 85.7 wt % with a FAME content of 73.6 wt %

[0105] Evaluation in Continuous Flow Reactor

[0106] The evaluation of heterogeneous acidic catalysts primarily Lewis to produce biodiesel by transesterification of triglyceride esters with alcohols in a heterogeneous phase in an upstream or downstream continuous flow reactor was carried out under the following conditions: LHSV=0.5 h.sup.−1, mole ratio methanol/oil (RM)=18, in an upflow microreaction plant, according to FIG. 5 where:

[0107] O=oil,

[0108] M=methanol,

[0109] C=catalyst,

[0110] R=tubular reactor,

[0111] S=separator,

[0112] M NR=unreacted methanol,

[0113] G=glycerol,

[0114] BD=biodiesel, and

[0115] O NR=unreacted oil

[0116] Tables 6 and 7 describe the properties of the catalysts evaluated in the continuous flow reactor, which were HLPA-16, whose composition is Al—Li—P, and HLPAM-3, whose composition is Al—Li—P—Mg, respectively.

TABLE-US-00006 TABLE 6 Catalyst Properties HLPA-16, used in the Examples of the present invention. Properties Composition.sup.1, weight % Value Lithium 1.95 Aluminum 7.59 Phosphorus 1.63 Particle size, mm 0.42-0.59 .sup.1dry basis

TABLE-US-00007 TABLE 7 Catalyst Properties HLPAM-3, used in the Examples of the present invention. Properties Composition.sup.1, weight % Valor Lithium 0.90 Aluminum 3.5 Phosphorus 0.43 Magnesium 1.6 Particle size, mm 0.42-0.59 .sup.1dry basis

Example 4

[0117] The evaluation of the HLPA-16 catalyst, the properties of which were described in Table 6, was carried out in the transesterification reaction of the RBD palm oil, with the properties presented in Table 1, and methanol, with the properties shown in Table 2. The test consisted of reaching the initial reaction conditions at LHSV=0.5 h.sup.−1, RM=18, 40 kg/cm.sup.2 pressure and 200° C. temperature and maintaining these conditions in ascending flow for a 24 hours term to attain the stability of the catalyst and the operation. Subsequently, 5 material balances of 12 hours each were made under these conditions, sampling the reactor products. The evaluation of this catalyst was continued with the temperature rise from 200 to 215° C. and the pressure was increased from 40 to 50 kg/cm.sup.2 to ensure that the reaction was carried out in liquid phase, keeping the other conditions constant, once reached the temperature, it was maintained at that point for 12 hours and 3 balances of 12 hours each were made. A transesterification product containing fatty acid methyl esters (FAME) was obtained in excess of 90%.

Example 5

[0118] The RBD palm oil, having the properties presented in Table 1, was subjected to the step of transesterification with methanol, with the properties shown in Table 2, using the heterogeneous catalyst HLPAM-3 whose composition is Al—Li—P—Mg with the properties described in Table 7. The transesterification reaction was carried out in a fixed-bed reactor with flow upstream to the operating conditions shown in Table. 8.

TABLE-US-00008 TABLE 8 Operating conditions of the catalytic transesterification step of the RBD palm oil of Example 5. Variable Condition Pressure, kg/cm.sup.2 40 Temperature, ° C. 200 Liquid hourly space velocity (LHSV), h.sup.−1 0.5 Mole ratio MeOH/Oil 18

[0119] The transesterified product was obtained with a biodlesel yield of 89.3 wt % with a FAME content of 89.6 wt %.

Example 6

[0120] According to Example 5, the catalytic transesterification step of the RBD palm oil using the heterogeneous catalyst HLPAM-3 of Table 7 was carried out under the operating conditions shown in Table 9.

TABLE-US-00009 TABLE 9 Operating conditions of the catalytic transesterification step of RBD palm oil of Example 6. Variable Condition Pressure, kg/cm.sup.2 40 Temperature, ° C. 215 Liquid hourly space velocity (LHSV), h.sup.−1 0.5 Mole ratio MeOH/Oil 18

[0121] The transesterified product was obtained with a biodiesel yield of 91.3 wt % with a FAME content of 91.4 wt %.

Example 7

[0122] According to Example 5, the catalytic transesterification step of the RBD palm oil using the prototype heterogeneous catalyst HLPAM-3 of Table 7 was carried out under the operating conditions shown in Table 10.

TABLE-US-00010 TABLE 10 Operating conditions of the catalytic transesterification step of the RBD palm oil of Example 7. Variable Condition Pressure, kg/cm.sup.2 55 Temperature, ° C. 220 Liquid hourly space velocity (LHSV), h.sup.−1 0.3 Mole ratio MeOH/Oil 18

[0123] The transesterified product was obtained with a biodiesel yield of 82.9 wt % with a FAME content of 93.7 wt %.

Example 8

[0124] According to Example 5, the catalytic transesterification step of the RBD palm oil using the prototype heterogeneous catalyst HLPAM-3 of Table 7 was carried out under the operating conditions shown in Table 11.

TABLE-US-00011 TABLE 11 Operating conditions of the catalytic transesterification step of the RBD palm oil of Example 8. Variable Condition Pressure, kg/cm.sup.2 55 Temperature, ° C. 220 Liquid hourly space velocity (LHSV), h.sup.−1 0.3 Mole ratio MeOH/Oil 36

[0125] The transesterified product was obtained with a biodlesel yield of 86.7 wt % with a FAME content of 96.0 wt %.

Example 9

[0126] According to Example 5, the catalytic transesterification step of the RBD palm oil using the prototype heterogeneous catalyst HLPAM-3 of Table 7 was carried out under the operating conditions shown in Table 12.

TABLE-US-00012 TABLE 12 Operating conditions of the catalytic transesterification step of the RBD palm oil of Example 9. Variable Condition Pressure, kg/cm.sup.2 70 Temperature, ° C. 230 Liquid hourly space velocity (LHSV), h.sup.−1 0.3 Mole ratio MeOH/Oil 18

[0127] The transesterified product was obtained with a biodiesel yield of 88.3 wt % with a FAME content of 91.9 wt %.

Example 10

[0128] According to Example 3, the step of catalytic transesterification of animal fat was carried out using a heterogeneous acidic catalyst with primarily Lewis nature in combination with a catalyst having an alkaline nature to produce biodlesel. The transesterification reaction was carried out in an upflow fixed bed reactor under the operating conditions shown in Table 13 to yield a transesterified product containing methyl esters of fatty acids (FAME).

TABLE-US-00013 TABLE 13 Operating conditions of the catalytic transesterification step of the RBD palm oil of Example 10. Variable Condition Pressure, kg/cm.sup.2 40 Temperature, ° C. 200 Liquid hourly space velocity (LHSV), h.sup.−1 0.5 Mole ratio MeOH/Oil 18

[0129] The transesterified product was obtained with a biodlesel yield of 87.9 wt % with a FAME content of 75.5 wt %.

Example 11

[0130] According to Example 3, the step of catalytic transesterification of animal fat was carried out using a heterogeneous acidic catalyst with primarily Lewis nature in combination with a catalyst having an alkaline nature to produce biodiesel. The transesterification reaction was carried out in an upflow fixed bed reactor under the operating conditions shown in Table 14 to give a transesterified product containing fatty acid methyl esters (FAME).

TABLE-US-00014 TABLE 14 Operating conditions of the catalytic transesterification step of palm oil RBD of Example 11. Variable Condition Pressure, kg/cm.sup.2 50 Temperature, ° C. 215 Liquid hourly space velocity (LHSV), h.sup.−1 0.5 Mole ratio MeOH/Oil 18

[0131] The transesterified product was obtained with a biodiesel yield of 87.6 wt % with a FAME content of 78.1 wt %.

Example 12

[0132] According to Example 3, the step of catalytic transesterification of animal fat was carried out using a heterogeneous acidic catalyst with primarily Lewis nature in combination with a catalyst having an alkaline nature to produce biodiesel. The transesterification reaction was carried out in an upflow fixed bed reactor under the operating conditions shown in Table 15 to give a transesterified product containing methyl esters of fatty acids (FAME).

TABLE-US-00015 TABLE 15 Operating conditions of the catalytic wtransesterification step of RBD palm oil of Example 12. Variable Condition Pressure, kg/cm.sup.2 40 Temperature, ° C. 200 Liquid hourly space velocity (LHSV), h.sup.−1 1.0 Mole ratio MeOH/Oil 18

[0133] The transesterified product was obtained with a biodiesel yield of 77.1 wt % with a FAME content of 67.2 wt %.

Example 13

[0134] According to Example 3, the step of catalytic transesterification of animal fat was carried out using a heterogeneous acidic catalyst with primarily Lewis nature in combination with a catalyst having an alkaline nature to produce biodiesel. The transesterification reaction was carried out in a fixed bed reactor upflow under the operating conditions shown in Table 16 to give a transesterified product containing fatty acid methyl esters (FAME).

TABLE-US-00016 TABLE 16 Operating conditions of the catalytic transesterification step of the RBD palm oil of Example 13. Variable Condition Pressure, kg/cm.sup.2 50 Temperature, ° C. 215 Liquid hourly space velocity (LHSV), h.sup.−1 1.0 Mole ratio MeOH/Oil 18

[0135] The transesterified product was obtained with a biodlesel yield of 87.1 wt % with a FAME content of 76.4 wt %.