BG65602B1 - Method for the production of alcohol esters of fatty acids and their application - Google Patents

Abstract

The invention relates to a method for the production of alcohol esters of fatty acids as biological fuel, which shall find application in all diesel engines. A complex of effective technological processes, which diminish its energy consumption, realizes the method. The part of jet reactors facilitates the occurring in them of re-esterification to 95% degree, and the use of purging column brings about complete separation of the glycerols, soaps and all mineral and organic impurities, and considerable amount of process water is economized. In the method, the degree of re-esterification reaches 99.9%, working at low temperatures and atmospheric pressure.

Description

The invention relates to a method for the production of alcoholic fatty acid esters and their use as biofuel. In particular, the invention also relates to the preparation of by-products such as glycerol for the pharmaceutical industry and potassium phosphate.

Biofuel is suitable for replacing diesel in diesel engines.

Interest in biofuels has intensified in recent years due to the drastic reduction of non-renewable sources of petroleum fuels and the deterioration of the greenhouse effect and acid rain.

BACKGROUND OF THE INVENTION

Catalytic alcohol is the basis of all processes for the production of low molecular weight esters from the triglycerides of natural oils and fats. This is the case whether seed transesterification (WO1997 / 038069) or oil transesterification (WO 1999/026913) is used. Alcoholysis takes place in the presence of a catalyst, otherwise this process is very slow and requires very high temperatures. Preferred catalysts are alkaline bases or alcoholic solutions of alkaline alcoholates and mineral acids. As the molecular weight of the alcohol used increases, the degree of alcoholism decreases - this is one of the reasons for the preference for low molecular weight alcohols - methanol, ethanol, propinol, butanol. Suitable raw materials for fatty acid esters are oilseeds and vegetable and animal fats and pure fatty acids.

The main disadvantage of the present methods is that they are economically inefficient as they require the use of expensive and complex equipment, high temperature of technological processes, large amount of process water, non-utilization of residual catalyst.

Explanation of the flow chart

A - common cooler to a common condensing system --- - a - jet reactor b - jet reactor

I - reactor

II - reactor

- alcohol and catalyst mixing tank

- glycerin water collection vessel

- power vessel

- Purification column

- dryer

- cooler

- filter

- distillation column

- residual catalyst separation reactor

- H ₃ PO ₄ storage vessel

- K ₃ PO ₄ separation filter

- separation court

- filter battery

- concentrator

SUMMARY OF THE INVENTION

The process is described in close connection with the attached scheme.

In tank "1" a mixture of preferred alcohol and catalyst is prepared, the catalyst varying from 0.5 to 50% of alcohol. It is possible to use primary and secondary monovalent alcohols with 1 to 8 carbon atoms - methyl, ethyl, propyl, butyl, hexyl, heptyl, octyl. Methyl alcohol is preferred. The catalysts that can be used are potassium and sodium bases, their alcoholates with various alcohols, mixtures of alcoholate and bases, sodium and potassium carbonate. Acids, such as sulfuric acid, can also be used as catalysts. It is preferable to use a potassium base as a catalyst at a temperature of from 15 to 65 ° C.

In reactor I, 2/3 of the required amount of mixture of alcohol and catalyst (which is 1-6 times the stoichiometrically calculated amount) is fed through jet reactor "a" simultaneously with the fats having a temperature of -15 to 100 °. S. Different vegetable oils, animal fats may be used2

65602 Bl and their mixtures or separate fatty acids and mixtures thereof. Vegetable oils that can be used are;

sunflower, rapeseed, mustard, cotton, coconut, palm, palm, corn, soy, peanut and more. Animal fats are different types of tallow - sheep, beef, duck, goose, etc., lard, various fatty acids and waste oils. As it enters reactor I, the mixture is stirred at speeds of 10 to 200 rpm.

After completion of the reaction in Reactor I, the glycerol obtained during this first stage of alcoholysis (90-95% transesterification rate) is taken to collecting vessel 2. The remaining reaction mixture at a temperature of 15 to 100 ° C is discharged through a jet reactor. " b ', together with the alcohol and catalyst mixture, is heated to not more than 65 ° C in reactor II and is left to rest until the process is completed. The degree of transesterification achieved is 99.9%. The glycerol layer was taken to a collection vessel 2.

The extracted esters are taken to a feed vessel 3, from which they pass through a purification column 4, which uses flushing water at a temperature of 5 to 100 ° C to remove impurities. Water can be acidified with 0.001% - 0.1% acetic or tannic acid. The washing water consumption in this type of column is very low from 0.5 to 5% of the esters passed.

The purified biofuel is taken to a drying apparatus 5 where it is dried at 80-100 ° C and a vacuum of 760 mHg to 0.5 mm Hg.

The dried biofuel goes to cooler 6, where it is cooled to 25 ° C in order to increase its low-temperature filtration and then filtered at a temperature of 5 to 25 ° C.

The filtered biofuel is taken for storage.

The biofuel thus obtained includes:

oleic methylate

- linoleic methylate

- palmitic methylate

- stearic methylate and optionally

- linolenic methylate

- eicosan methylate from 5 to 82% from 1.2 to 64% from 0.3 to 48.5% from 0.7 to 28.9% from 0.2 to 9% from 0.8 to 10% from 0, 3 to 1% from 32.2 to 63% from 1.3 to 16.4% from 0 to 3% from 0 to 4.2% from 0 to 4.3%

- erucic methylate

- lauric methylate

- myristic methylate

- Capron methylate

- Capricious methylate

- caprylic methylate

Glycerin water from collecting vessel 2 is discharged into distillation column 8 to remove residual alcohol at a temperature of 60 to 100 ° C, which is related to the general condensation system A, which reduces alcohol losses and to which reactors I and II are included , the feed vessel 3, the purification column 4 and the collecting vessel 2. The glycerol 15 water containing no residual alcohol is discharged into the reactor 9. From the feed vessel 10 to the glycerol water, mineral acid H ₃ PO ₄ is added to the reactor with a concentration of 1 to 100%. . The amount used is 0.01-5%, preferably 20%. After completion of the reaction / up to a maximum of 12 hours / the reaction mixture was passed through a filter 11 for complete separation of potassium phosphate and taken to a separation vessel 12.

The glycerol waters of the separation vessel 12 pass through a battery of filters 13 using ion exchange resins: to whiten a highly basic macroporous type ion-exchange resin based on polystyrene and to purify 30 in a row of acidic gel-like cationite, weakly basic anionic maceritone styrene and divinylbenzene, a mixture of highly basic macroporous anionite type I based on the copolymerization of styrene and divinyl3 5 benzene and a strong acid gel cation exchange resin 1: 1, this method replacing the process distillation of glycerin, reducing its cost. The glycerol waters were concentrated to the desired percentage in concentrator 14.

The finished glycerin is taken away for storage.

The separated fatty acids from the separating vessel 12 are taken for storage.

All vessels in the process line are connected in a common condensation system to condense alcohol vapors, eliminating alcohol losses.

Its advantage is that it is environmentally friendly - it also has low emissions, lacks sulfur and is degradable.

The advantage of the present invention

65602 Bl is that a method has been devised, however, which is continuous and economical and achieves a 99.9% re-esterification rate. The use of a purification column operating on the principle of the interaction of two liquids, one of which is in a compact state and the other in a droplet state leads to the complete separation of residual alcohol, glycerin and soaps and mineral and organic impurities, thereby the process is very efficient. With the appropriate catalyst selected, it is possible to process crude vegetable and animal fats, waste oils and fatty acids and mixtures thereof, in which very small amounts of soap are formed, which are subsequently easily cleaned, thereby the process takes place at atmospheric pressure and at low temperatures.

Examples of use of the invention

Example 1. 20

Crude sunflower oil (without undergoing any treatment) was used for this experiment, with the following parameters: acidity 1.5%; moisture 0.3%.

Pre-mix CH ₃ OH and KOH 25 in a molar alcohol-base ratio of 6: 0.15.

Two thirds of this mixture (alcohol and base) and all the oil at a temperature of about 60 ° C are mixed through a jet reactor "a", adjusted so that the two streams entering it at the same time end 30.

Entering reactor I, the reaction mixture was stirred at 120 rpm. Immediately after transferring the entire amount of the reaction mixture, the stirrer stops and begins the drainage of the regulated glycerol phase, 35 to be completed with the separation of the two phases.

The reaction mixture (ester phase) and the remaining one-third of the alcohol and base mixture were passed through a second jet reactor "b", re-equilibrated so that the mixtures flow simultaneously at a temperature of about 65 ° C and the resulting mixture enters reactor II , where glycerol phase separation begins immediately and ends after complete separation of the two phases. The degree of esterification achieved after this second step is 99.9%.

The ester phase passes through a purification column "4", operating on the principle of the interaction of two liquids, one of which is in a compact state and the other in a droplet. The stationary phase is initially water, acidified with 0.01% acetic acid.

The high degree of purification of methyl esters is ensured by adjusting the following indicators:

- total glycerol content

- catalyst and methanol content.

When their content exceeds 0.001% in esters, part of the glycerol-saturated aqueous phase is automatically drained from the column and supplemented with acidification water from 0.5 to 5%.

The methyl esters, purified from residual alcohol, glycerol, soaps and all mineral and organic impurities are dried in vacuo at about 100 ° C, then cooled to 20 ° C and filtered.

The resulting mixture, which is used as a fuel, contains the following methyl esters:

oleic methylate 30% - linoleic methylate 63% - palmitic methylate 3% - stearic methylate 4% And the indicators that her define as bi- fuel in the analysis, - viscosity at 40 ° C 4 cc - flash point 148 ° C is a cetane number 62

The glycerol phase is treated as follows.

The effluent drained from the purification column is added to the glycerol phase and the remaining alcohol is distilled off from these glycerol waters. To the non-alcoholic glycerol water, 1% phosphoric acid was added with constant stirring. After the separation of the fatty acids, the treated glycerol waters pass through a battery of filters using ion-exchange resins: to whiten a highly basic macroporous type ion-exchange resin based on polystyrene and to desalinate a series of highly acidic gel-like cationitron copolymeritolitomers styrene and divinylbenzene, a mixture of highly basic macroporous anionite type I based on the copolymerization of styrene and divinylbenzene and a strong acid gel cation exchange resin in a ratio of 1: 1, which allowed post-concentration to obtain glycerol, response4

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in addition to that of distilled glycerin. - viscosity at 40 ° C 3.8 ssgp Example 2. - flash point 129 ° C Rapeseed oil was used for this experiment cetane number 59 indicators: acidity 4%; moisture 0.5%. Example 5. The oil was processed according to technological 5 Coconut oil with acid- of the Scheme of Example 1 to give a mixture which 3%; moisture 0,2%. is used as biofuel containing the following Oil treatment is more scheme of the following methyl esters: measure 1, as before the jet reactor oil oleic methylate 55% must be liquefied. - linoleic methylate 20% 10 A mixture is obtained which is used as - linolenic methylate 9% biofuel containing the following methyl - palmitic methylate 5% esters: - stearic methylate 1% oleic methylate 5% - eicosan methylate 9% - linoleic methylate 2% - erucic methylate 1% 15 - palmitic methylate 15% And the indicators that determine i like bio- - stearic methylate 8.5% in the analyzes performed are: - lauric methylate 58% - viscosity at 40 ° C 4.5 pc - myristic methylate 11,5% - flash point 130 ° C And the indicators that determine i like bio- is a cetane number 54 20 in the analyzes performed are: Example 3. - viscosity at 40 ° C 4.8 pp Raw maize was used in the experiment - flash point 140 ° C oil with indicators: acidity 8%; moisture of 1%. is a cetane number 50 The oil is treated according to the scheme of Example 6 measure 1 and the resulting mixture to be used as 25 The processed oil is palm (from pal- biofuel containing the following methyl nuts) with an acidity of 5%; moisture 0.5%. esters: The oil is treated by the example scheme - linoleic methylate 58% 1, as required before the jet reactor oleic methylate 24,2% be liquefied. - stearic methylate 1.8% 30 The resulting mixture to be used as bi- - palmitic methylate 10.9% a fuel contains the following methyl esters: - linolenic methylate 0.7% oleic methylate 11,4% Defendants defining like biogori- - linoleic methylate 1.6% in the analyzes performed are: - palmitic methylate 8.1% - viscosity at 40 ° C 4.2 US 35 - stearic methylate 2.8% - flash point 148 ° C - myristic methylate 16.4% is a cetane number 53 - lauric methylate 48,2% Example 4. - Capron methylate 3% Crude soybean oil with - Capricious methylate 4.2% indicators: acidity 10%; moisture of 1%. 40 - caprylic methylate 4.3%. Mixture of methyl esters obtained after And the indicators that define it as bi- oil treatment according to the scheme of Example 1, the fuel in the analyzes made are: which is used as biofuel is the following: - viscosity at 40 ° C 5th c oleic methylate 30% - flash point 128 ° C - linoleic methylate 49% 45 is a cetane number 50 - linolenic methylate 8% Example 7. - palmitic methylate 10% Palm oil with acidity was used

- stearic methylate 3%

And the indicators that define it as biofuel in the analyzes are:

7%; moisture 0.5%.

The processing is according to the scheme of Example 1.

The resulting mixture to be used as bi50

65602 Bl fuel contains the following methyl esters:

- stearic methylate 4,3%

- oleic methylate 36,6%

-Linol Methylate 9.1%

- linolenic methylate 0,2%

- palmitic methylate 48,5%

-myristine methylate 1,3%

And the indicators that define it as biofuel in the analyzes are:

- viscosity at 40 ° C 5 cc

- flash point 125 ° C

is a cetane number 56

Example 8.

The oil used is olive with an acidity of 0.5%; moisture of 0.1%.

A mixture was obtained which was used as biofuel after processing according to the scheme of Example 1 and contained the following methyl esters:

- oleic methylate 82%

- linoleic methylate 1.5%

- myristic methylate 1,3%

- palmitic methylate 14%

- stearic methylate 1,8%

And the indicators that define it as biofuel in the analyzes are:

- viscosity at 40 ° C 4 cm

- flash point 142 ° C

is a cetane number 59

Example 9.

Cottonseed oil with an acidity of 2.8% was used in this experiment; moisture 0,2%.

The treatment of the oil is according to the scheme of Example 1. A mixture is obtained which is used as a biofuel and contains the following methyl esters:

- palmitic methylate 22,7% - stearic methylate 2.3% ooleic methylate 17% - linoleic methylate 51.5% - linolenic methylate 0.2% And the indicators that determine i like bio- in the analyzes performed are: - viscosity at 40 ° C 5th c - flash point 153 ° C is a cetane number 60

Example 10.

Fatty acids were used in this experiment.

The treatment of fatty acids is also in the flowchart of Example 1, in which case it is not the glycerin phase which is separated but the reaction waters that are not treated.

Depending on what oil was obtained, the fatty acids obtained during the tests were blends that were used as biofuels having the following methyl ester composition and performance:

1. Raw material: Sunflower oil fatty acids

Composition:

oleic methylate 28% - linoleic methylate 64% - palmitic methylate 4% - stearic methylate 4% Indicators: - viscosity at 40 ° C 4.1 pp - flash point 150 ° C is a cetane number 59 2. Raw material: rapeseed fatty acids butter Composition: oleic methylate 58% - linoleic methylate 18.3% - linolenic methylate 8.2% - palmitic methylate 4,5% - eicosan methylate 10% - stearic methylate 0.7% - erucic methylate 0.3% Indicators: - viscosity at 40 ° C 4 cc - flash point 130 ° C is a cetane number 56 3. Raw material: soy fatty acids lo Composition: oleic methylate 28% - linoleic methylate 51% - linolenic methylate 6.2% - palmitic methylate 11% - stearic methylate 3,8% Indicators: - viscosity at 40 ° C 3.6 pcs - flash point 130 ° C is a cetane number 58 4. Raw material: a mixture of fatty acids, extracted from coconut and palm oil Composition: oleic methylate 8% - linoleic methylate 1.2% - palmitic methylate 13% - stearic methylate 8% - lauric methylate 63%

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- myristic methylate 6,8%

Indicators:

- viscosity at 40 ° C 5 cc

- flash point 125 ° C

is a cetane number 50

Example 11.

In this experience, used oil collected from various food establishments and restaurants was used.

The oil is treated in the same way, first filtered if necessary to retain solids (food residues).

The resulting mixture, which is used as biofuel, contains the following methyl esters:

oleic methylate 15.6%

- linoleic methylate 38,1%

- palmitic methylate 0,6%

- stearic methylate 1%

- myristic methylate 5,2%

- lauric methylate 39.5%

And the indicators that define it as biofuel in the analyzes are:

- viscosity at 40 ° C, 4.1 cc

- flash point 140 ° C

is a cetane number 58

Example 12.

Duck fat with an acidity of 28% was used for this experiment; moisture 3%.

The treatment of lute is according to the flowchart of Example 1, with the liquid being liquefied before the jet reactor. The Vulkanox-BHT additive was added to the reaction mixture in an amount of 0.001%.

A mixture is obtained which is used as biofuel and contains the following methyl esters:

oleic methylate 37% - linoleic methylate 2.2% - myristic methylate 3.3% - palmitic methylate 30% - stearic methylate 18.8% And the indicators that characterize it as biofuels are: - viscosity at 40 ° C 4.5 pc - flash point 153 ° C is a cetane number 52

Example 13.

Pig fat was used for this experiment.

The processing of bridges into methyl esters is carried out according to the technological scheme after liquefaction and before the jet reactor.

A mixture is obtained which is used as biofuel and contains the following methyl esters:

oleic methylate 53% - palmitic methylate 21.5% - stearic methylate 16.2% - other methyl esters 9.3% And the indicators that characterize it as

biofuels are:

- viscosity at 40 ° C 5 cc

- flash point 150 ° C

is a cetane number 59

Example 14.

Beef tallow was used for this experiment.

Pre-liquefied tallow is treated according to the flow chart of Example 1.

A mixture is obtained which is used as biofuel and contains the following methyl esters:

- myristic methylate 3.7% - palmitic methylate 27.9% - stearic methylate 28.9% oleic methylate 36% - linoleic methylate 3.1% - linolenic methylate 0.6% - eicosan methylate 0,8% And the indicators that characterize it as biofuels are: - viscosity at 40 ° C 4.8 pp - flash point 149 ° C is a cetane number 58 Example 15. Mixtures of different oils and the fats treated according to the one given in Example 1 scheme. 1. A mixture of 90% crude sunflower oil- loo and 10% duck fat. The resulting mixture which used as a bi- a fuel contains the following methyl esters: oleic methylate 29.2% - linoleic methylate 58,3% - palmitic methylate 3.5% - stearic methylate 6% - myristic methylate 3% And the indicators that characterize it as biofuels are: - viscosity at 40 ° C 4 cc - flash point 139 ° C is a cetane number 55

2. Raw material: a mixture of 90% crude rapeseed oil and 10% lard.

The resulting mixture to be used as bi7

65602 Bl

a fuel contains the following methyl esters: oleic methylate 54.8% - linoleic methylate 18.2% - linolenic methylate 8.9% - palmitic methylate 6.3% 5 - stearic methylate 2.8% - eicosan methylate 8,3% - erucic methylate 0.7% And the indicators that characterize it as biofuels are: 10 - viscosity at 40 ° C 3.8 ss - flash point 149 ° C is a cetane number 60 3. Raw material: a mixture of 70% raw sun- ice oil and 30% palm oil 15

The resulting mixture to be used as bi-

a fuel contains the following methyl esters: oleic methylate 17% - linoleic methylate 38.5% - palmitic methylate 0.3% 20 - stearic methylate 0.7% - myristic methylate 4.2% - lauric methylate 38.9% - others 0.4%. And the indicators that characterize it as 25 biofuels are: - viscosity at 40 ° C 3.6 ss - flash point 150 ° C is a cetane number 59

4. Raw material: a mixture of 50% crude sunflower oil and 50% waste oil

The resulting mixture to be used as bi-

a fuel contains the following methyl esters: oleic methylate 22% - linoleic methylate 30,8% - palmitic methylate 2.7% - stearic methylate 3.1% - myristic methylate 8.9% - lauric methylate 32,2% - others 0.3% And the indicators that characterize it as biofuels are: - viscosity at 40 ° C 4.1 US - flash point 142 ° C

is a cetane number 58

Example 16.

Different alcohols and catalysts were used in this experiment. The molar ratios and treatment are according to the flow chart of Example 1. All the experiments with different oils and fats from Example 1 to Example 15 were repeated.

The percentage composition of the esters obtained is the same as in the relevant examples, and the performance indicators are given in the following table.

16.1. Ethyl alcohol and sodium hydroxide catalyst used.

Used oil Viscosity at 40 ° C Flash point Cetane number Crude sunflower oil 3.8 145 58 Crude rapeseed oil 4.2 128 52 Crude corn oil 4 147 51 Crude soybean oil 3.9 128 56 Crude coconut oil 4.5 139 49 Crude palm oil 4,8 129 53 Crude palm oil 4,8 123 54 Crude olive oil 4.2 140 56 Crude cottonseed oil 4,8 150 55 Fatty acids (mixture) 4 150 54 Used oil 4 140 52 Duck fat 4.5 152 50 Lard 4,8 148 55 Beef tallow 4.9 147 53 A mixture of 90% pane and 10% wt 4,8 140 53

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16.2. Isopropyl alcohol and sodium catalyst were used. The molar ratios are the same as in Example 1. The test was made with all the oils and fats used from Example 1 to Example 15. The percentage composition of the isopropyl esters obtained corresponds to the percentage composition of the methyl esters obtained in the corresponding examples, and the indicators to which the esters obtained correspond and characterize them as biofuels 5 are presented in the following table.

Used oil Viscosity at 40 ° C Flash point Cetane number Crude sunflower oil 3.9 150 53 Crude rapeseed oil 4 149 50 Crude corn oil 4,1 138 49 Crude soybean oil 3.5 125 54 Crude coconut oil 4.2 140 49 Crude palm oil 4.5 135 50 Crude palm oil 4,8 128 50 Crude olive oil 4.9 139 51 Crude cottonseed oil 4 155 51 Fatty acids (mixture) 4.3 153 52 Used oil 4,1 149 50 Duck fat 4.5 150 49 Lard 4.6 145 49 Beef tallow 4.3 144 52 A mixture of 90% rapeseed and 10% pork 3.8 148 50

Claims

Claims (9)

1. A method for the production of a mixture of alcoholic fatty acid esters, characterized in that it consists of: - preparing a mixture of alcohol and catalyst, wherein the catalyst ranges from 0.5 to 50% and has a temperature of 15 to 65 ° C; - feeding two-thirds of the resulting mixture, together with the fats having a temperature of -15 to 100 ° C, through a jet reactor (a) into a stirring reactor (I), where the mixture of reagents is stirred at 10 rpm up to 20 rpm; - removing the glycerin obtained from the previous step into the collecting vessel (2), and the remaining reaction mixture together with the remaining one-third alcohol / catalyst mixture through a jet reactor (b), where the product temperature is between 15 and 100 ° C, into a reactor (N), where the process is at rest and the glycerin layer formed here is taken to a collecting vessel (2); - removing the resulting ester mixture into a supply vessel (3); - passing the resulting ester mixture through a purification column (4) into which the impurities are separated by washing water; draining the purified mixture into a drying apparatus (5) wherein the drying temperature is from 80 to 100 ° C; - passing the mixture to a cooler (6) where cooling to 25 ° C is carried out; - filtration of the cooled mixture at a temperature of from 5 to 25 ° C and removal for storage; - subjecting the glycerol water from the collection vessel (2) to distillation in a distillation column (8) to remove the remaining alcohol at a temperature of 60 to 100 ° C, with the column (8) connected to the common condensation system (A); - withdrawing the glycerol water into a reactor (9), where phosphoric acid in an amount of 0.01 to 5% is added from the vessel (10); - passing the mixture from the previous step through a filter (11) to remove potassium phosphate50 65602 B1 velvet and removal to a separation vessel (12); - removing the fatty acids for storage, and passing the glycerin water through the batteries of the filters (13), into the concentrator for concentration, and removing the glycerin for storage. A method according to claim 1, characterized in that the fat is vegetable: sunflower, rapeseed, mustard, cotton, coconut, palm, palmitic, corn, soybean, peanut; animal - pig, sheep, beef, duck, goose; used fat and fatty acids. 3. The method of claim 1, wherein the alcohol is methyl, ethyl, propyl, butyl, hexyl, heptyl, oxyl. 4. The method of claim 1, wherein the catalyst is potassium base or sulfuric acid. 5. A method according to claim 1, characterized in that the purification column (4) operates in a mode of interaction of the two liquids, the water being compact and the mixture dripping. Method according to claim 1, characterized in that the reactors (I, II), the supply vessel (3), the purification column (4) and the collecting vessel (2) are all connected in a single condensation system (A). Method according to claim 1, characterized in that the phosphoric acid is added in an amount of 1%. A method according to claim 1, characterized in that the filter batteries (13) are ion exchange resins: in the order of a highly basic macroporous type ion exchange resin based on polystyrene; strong acid gel cation exchanger; weakly basic macroporous anionite based on the copolymerization of styrene and divinylbenzene; a mixture of highly basic macroporous anionite type I based on the copolymerization of styrene and divinylbenzene and strong acid cationite in a ratio of 1: 1. A mixture of esters obtained according to the method of claims 1 to 8, characterized in that it comprises: oleic methylate from 5 to 82% - linoleic methylate from 1.2 to 64% - palmitic methylate from 0.3 to 48.5% - stearic methylate from 0.7 to 28.9%, and in one case, - linolenic methylate 0.2 to 9% - eicosan methylate 0.8 to 10% - erugov methylate from 0.3 to 1% - lauric methylate from 32.2 to 63% - meristin methylate from 1.3 to 16.4% - Capron methylate from 0.01 to 3% - Capricious methylate from 0.01 to 4.2% - caprylic methylate from 0.01 to 4.3%. 10. Use of a mixture of esters according to but claim 9 as biofuel. Attachment: 1 figure