The method of obtaining of ester by the esterification reaction
(57) Abstract:The invention relates to a process for the preparation of ester, which comprises carrying out the esterification reaction in the presence of a catalyst which is a reaction product of artefiera or condensed orthoevra titanium or zirconium and alcohol containing at least two hydroxyl group of 2-hydroxycarboxylic acids and bases. Ortofon has the formula M(OR)4where M is titanium or zirconium and R is preferably1-6alkyl group. Condensed Ortofon has the formula1O[M(OR1)2O]nR1where R1preferably is C1-6alkyl group, M is titanium or zirconium, and n is preferably less than 20. The method can be direct esterification, transesterification or polyesterification. The technical result - the production of esters without the turbidity of the final product and with the reduced degree of yellowing of esters. 19 C. p. F.-ly, 4 PL. The invention relates to a method of esterification, in particular the method of esterification, which applies the new technoorganic or Circonvallazione catalyst.For sportation as catalysts. During the esterification of these compounds usually turn into polymeric compounds of titanium, which can lead to opaque (whitish) product. The presence of turbidity is a specific lack of polyesters, which have a higher viscosity and/or high melting point, and therefore they are difficult to filter. In addition, it is known that many technoorganic compounds that are effective catalysts in the production of polyesters such as polyethylene terephthalate, give undesirable yellowing of the final polymer.The purpose of this invention is the provision of an improved method of producing esters.In accordance with the invention, a method of obtaining a complex ester comprises carrying out the esterification reaction in the presence of a catalyst comprising the reaction product of artefiera or condensed orthoevra titanium or zirconium, alcohol containing at least two hydroxyl group of 2-hydroxycarboxylic acids and bases.The esterification reaction of the method of the invention can be any reaction, through which the ester. The reaction can be direct these is a, or transesterification (alcoholysis), in which the first alcohol interacts with the first complex ester with formation of ester of the first alcohol and the second alcohol obtained by splitting the first of ester, or interesterification reaction in which two of ester interact with the formation of two other esters by sharing CNS radicals. Direct esterification or transesterification can be used in the production of polymers of ester, and the preferred method of the invention includes a method of polyesterification.When direct esterification can be used many carboxylic acids and anhydrides, which include saturated and unsaturated monocarboxylic acids, such as stearic acid, isostearoyl acid, capric acid, Caproic acid, palmitic acid, oleic acid, palmitoleic acid, triacontanoic acid, benzoic acid, methylbenzoic acid and salicylic acid; dicarboxylic acids, for example phthalic acid, isophthalic acid, terephthalic acid, sabotinova acid, adipic acid, azelaic acid, succinic acid, fumaric acid, maleic acid, naphtaline the new acid, citric acid, timesyou acid, pyromellitic acid and anhydrides of these acids. Alcohols typically used for direct esterification include aliphatic monohydroxy alcohols with straight and branched chain, for example butyl, pentalogy, hexyl, oktilovom and stearyl alcohols, and polyhydric alcohols such as glycerol and pentaerythritol. Especially preferred method of the invention includes the interaction of 2-ethylhexanol with phthalic anhydride with the formation of bis(2-ethylhexylphthalate).Because during the esterification reaction of substituted alcohol by distillation are usually eliminated, esters, used in the reaction alkalize are usually lower homologues, such as methyl, ethyl and propyl esters. In the method of the invention using such esters of the acids suitable for direct esterification. Usually meth(acrylate) esters of alcohols with long chain obtained by the alcoholysis of esters, such as methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate. Typical alcohols used in the reaction of alcoholysis, include butyl, hexyl, n-oktilovom and 2-ethylhexyloxy alcohols and substituted alcohols, for example, dimethylamine usually chosen so to provide a volatile ester, which can be removed by distillation.As mentioned above, polymers of esters can be obtained by methods that include direct esterification or transesterification, and particularly preferred variant of the method of the invention is the reaction of polyesterification in the presence of the previously described catalyst. In the reaction of polyesterification polybasic acid or esters of polybasic acids interact normally with polyhydric alcohols to form polymers of esters. Linear polyesters derived from dibasic acids, for example, from those mentioned above, or esters of dibasic acids and diatomic alcohols. Preferred reaction polyesterification in accordance with the invention include the reaction of interaction of terephthalic acid or dimethyl terephthalate 1,2-ethanediol (ethylene glycol) to produce polyethylene terephthalate or 1,4-butanediol (butyleneglycol) to produce polybutylene terephthalate or reaction naphthaleneboronic acid with 1,2-ethanediol with getting polyethylenenaphtalene. To obtain polyesters are also suitable other glycols, such is ethyleneterephthalate includes two stages. In the first stage of terephthalic acid or terephthalate interacts with 1,2-ethanediol with the formation of the prepolymer and by-products of water and methanol are removed. In the second stage, the prepolymer is then heated to remove 1,2-ethanediol and form a long chain polymer. The method in accordance with the invention may include one or phase, or both phases.The catalyst used in the method of the invention is the reaction product of artefiera or condensed complex ester of titanium or zirconium, alcohol containing at least two hydroxyl group of 2-hydroxycarboxylic acids and bases. Orthoepy preferably has the formula: M(or SIG)4in which M is titanium or zirconium and R is an alkyl group. More preferably, R contains from 1 to 6 carbon atoms, and, in particular, suitable areavery include tetraisopropoxide, Tetra-n-butoxysilane, Tetra-n-propoxycarbonyl and Tetra-n-butoxysilane.Condensed areavery suitable for the preparation of catalysts suitable in this invention usually get by careful hydrolysis of orthoepical titanium or zirconium, and they are typically of through which M is titanium or zirconium. The value of n is preferably less than 20 and more preferably n is less than 10. R1preferably contains from 1 to 6 carbon atoms and suitable condensed areavery include compounds that are known as polybutylene, polyisopropylene and polybutylene. Alcohol containing at least two hydroxyl groups, preferably is a diatomic alcohol and may be 1,2-diol, for example, 1,2-ethanediol, 1,2-propandiol; 1,3-diol, for example, 1,3-propandiol, or diatomic alcohol containing longer chain, for example, diethylene glycol or polyethylene glycol. Preferred diatomic alcohols are 1,2-ethanediol and diethylene glycol. The catalyst can be obtained from polynuclear alcohol, for example glycerol, trimethylolpropane or pentaerythritol.The catalyst preferably is produced by the interaction of a diatomic alcohol with orthoevra or condensed orthoevra at a ratio of from 2 to 12 moles of a diatomic alcohol to each pray titanium or zirconium. More preferably, the reaction product contains from 4 to 8 moles of a diatomic alcohol per mole of titanium or zirconium.Preferred 2-hydroxycarboxylic acids include lactic kikoti water mixtures. Acid in this form, as well as anhydrous acids are suitable for the preparation of the catalyst used in this invention. The preferred molar ratio of acid to titanium or zirconium in the reaction product is about 1 to 4 moles per mole of titanium or zirconium. More preferably, the catalyst contains from 1.5 to 3.5 moles of a hydroxy acid per mole of titanium or zirconium.To obtain the reaction product, which is used as a catalyst in the method of the invention, used as the basis. Base, typically an inorganic base, and suitable bases include sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium carbonate, magnesium hydroxide and ammonia. The amount of base is usually sufficient for the neutralization of the 2-hydroxycarboxylic acid, but the complete neutralization of the acid is not significant. Therefore, the preferred amount of base to neutralize yielding 2-hydroxy acids, such as lactic acid, is in the range from 0.8 mol to 1.2 mol per mole of 2-hydroxy acid. In the case of citric acid (trehosnovnoy acid) is preferred amount is in the range from 1 to 3 moles of base per mole of 2-oxetane or zirconium, and preferably the amount of base is from 1 to 4 moles per mole of titanium or zirconium.Typically, the catalysts of the invention are neutral. Upon receipt of the catalysts are usually together with the base add water. Foods that contain water, typically have a pH in the range from 6 to 8. The catalyst may be obtained by mixing components (orthoevra or condensed orthoevra, diatomic alcohol, 2-oxy-acids and bases) while removing by-product (for example, isopropyl alcohol, when arteparon is tetraisopropoxide) at any appropriate stage. In one preferred method mix orthoepy or condensed orthoepy and diatomic alcohol and subsequently add 2-hydroxy acid and then base or pre-neutralized solution of 2-hydroxy acid. In an alternative preferred method orthoepy or condensed orthoepy interacts with 2-oxicology and a by-product, which is the alcohol removed. Then, to this reaction product is added a base, then add a diatomic alcohol and get a reaction product, which is the catalyst for the method of the invention. Optionally, an additional by-product, which is the alcohol can then be removed by distillation.R is used when carrying out the esterification reaction.When the direct esterification of the acid or anhydride and an excess of alcohol is usually heated, if necessary, in a solvent in the presence of a catalyst. Water is usually a byproduct of the reaction and it is removed in the form of an azeotrope with a boiling mixture of solvent and/or alcohol. Typically, the mixture of solvent and/or alcohol, which is subjected to condensation, not miscible with water, which therefore is separated before the solvent and/or alcohol are returned to the reaction vessel. When the reaction is completed, excess alcohol and the solvent, if used, is evaporated. In contrast to the methods of esterification of the preceding field is usually not necessary to remove the catalyst from the reaction mixture. A typical reaction of the direct esterification is to obtain bis(2-ethylhexyl)phthalate, which is obtained by mixing phthalic anhydride and 2-ethylhexanol. Initial reaction, which is formed of monoether, is fast, and the subsequent conversion of monoether in fluids is carried out by heating in a flask with reflux condenser at a temperature of 180-200oIn the presence of a catalyst until then, until all the water is removed. Then remove the excess alcohol.In R) is often removed by distillation in the form of an azeotrope with complex ether. Is usually necessary steam fractionation of the mixture obtained in the United States, to ensure effective separation of the second alcohol without significant loss of ester obtained first or alcohol. The conditions under which conduct the reaction of alcoholysis, depend mainly on the components of the reaction and, as a rule, the components are heated to the boiling point of the mixture used.The preferred method of the invention is to obtain polyethylene terephthalate. Typical periodic obtaining of polyethylene terephthalate is carried out by loading into the reactor terephthalic acid and ethylene glycol, optionally together with a catalyst and heating the contents to 260-270oWith under a pressure of about 0.3 MPa. When at a temperature of about 230oWith acid will dissolve and the water is removed, the reaction begins. The product is transferred to the second autoclave and, if necessary, add the catalyst. To remove a by-product of ethylene glycol reactor is heated up to 290-300oWith under a vacuum of 100 PA. Molten obtained ester is unloaded from the reactor, cooled and crushed.The amount of catalyst used in the method of the invention, usually depends on the content of the action direct esterification or interesterification is from 30 to 1000 parts per million (ppm) relative to the weight of ester obtained. The amount of catalyst is preferably from 30 to 450 parts per million relative to the weight obtained of ester and more preferably from 50 to 450 parts per million relative to the weight of ester obtained. In the reactions of polyesterification used a number usually expressed in a percentage weight of the obtained polyester and it usually takes from 5 to 500 ppm in terms of Ti or Zr relative to the derived complex ester. Preferably the amount is from 5 to 100 ppm in terms of Ti or Zr.The method of this invention compared with methods that use known catalysts, provides an efficient and economical production of esters and polyesters without the turbidity of the final product and with the reduced degree of turbidity polyesters.The invention will be illustrated using the following examples.Obtaining catalysts.Example 1.In a 1 l flask equipped with stirrer, condenser and thermometer to stir isopropoxide titanium (284,8 g, 1.00 mol) of the dropping funnel were added ethylene glycol (217,85 g, 3,51 mol). The rate of addition was regulated so clicks esale within 15 minutes and the reaction flask to ensure a transparent pale yellow liquid (the content of Ti is 6.54% by weight) was added aqueous 85% by weight. % solution of ammonium lactate (251,98 g, 2.00 mmole).Example 2.Following the procedure of example 1, to isopropoxide titanium (284,8 g, 1.0 mol) was added ethylene glycol (496,37 g to 8.0 moles) to the reaction mixture was added aqueous 60 wt. % solution of sodium lactate (374,48 g, 2,0 mol), at the same time would yield a pale yellow liquid (Ti content of 4.13% by weight).Example 3.In a 1 l conical flask equipped with condenser and magnetic stirrer, to isopropoxide titanium (142,50 g, and 0.50 moles) of a dropping funnel was slowly added ethylene glycol (248,25 g to 4.0 mol). When the addition was completed, the contents of the flask before the addition of the dropping funnel water 60 wt. % solution of ammonium lactate (213,03 g, 1.0 mol) was subjected to stirring, the result was very clear pale yellow product (the content of Ti 3,91% by weight).Example 4.Following the procedure of example 3, to 135,95 g (0,3 mol) of n-propoxide zirconium (72,3 wt. % n-propanol) was added diethylene glycol (127,58 g of 1.20 mol). To this mixed product was added aqueous 60 wt. % solution of ammonium lactate (112,04 g to 0.60 moles), resulted in a pale yellow product (the content of Zr 7,28% by weight).Example 5.In a 1 l flask equipped with a mixer, to economy the solution from the dropping funnel was slowly added isopropoxide titanium (71,0 g, of 0.25 mol) the Mixture was heated in a flask under reflux for 1 h to obtain a turbid solution, which under vacuum drove a mixture of isopropanol and water. The product is cooled to a temperature below 70oWith and to the mixed solution using a dropping funnel was slowly added 32 wt. % aqueous NaOH solution (94,86 g, from 0.76 mol). The obtained product was filtered, then mixed with ethylene glycol (125,54 g, 2,0 mol) and heated under vacuum to remove isopropanol and water, got a slightly cloudy pale yellow product (the Ti content of 3.85% by weight).The sensitivity of the product of example 5 to interact with coloring substances was determined by mixing the catalyst with a dilute solution of diethyldithiocarbamate in toluene (0.04 g/ml). The color of the resulting solution was determined on a spectrophotometer LICO 200 11 mm cylindrical cuvette and compared with the solution containing tetraisopropoxide [Ti(OiWG)4] . The results are shown in table. 1 (see the end of the description).Etherification
Example 6.The products of examples 3, 4 and 5 were tested as catalysts for the equivalent level of metal (Ti or Zr), necessary to obtain bis(2-ethylhexylphthalate). As relatively the value of the test was one litre chetyrehkolka round-bottom flask, equipped with a thermometer, a rubber sealing material, the tube is submerged beneath the surface of the reagents and apparatus Dean and stark. The equipment was operated under reduced pressure, with used oil vacuum pump connected to two water condensers above equipment Dean and stark. Immersed tube connected with a supply of nitrogen, which does not contain oxygen. The venting tube for nitrogen facilitated the removal of water formed during the reaction.To 2,42 the moles (315 g), 2-etilenglikola added 1.0 mol (148 g) and phthalic anhydride. To dissolve the phthalic anhydride, the mixture was heated and filed a stream of nitrogen.When the temperature reached 180oWith, through the rubber sealing material with a syringe under the surface of the reagents added to the weighed amount of the catalyst. By proper regulation of the speed of heating and vacuum, the reaction mixture is maintained under conditions of rapid heating under reflux. The obtained water was removed essentially as soon as it was formed and collected in the apparatus of Dean and stark. As the reaction after a certain period of time by means of a syringe fitted with a 30-Sant the promotional mix to each sample is added to a known quantity (approximately 100 g) chilled alcohol, weighed and titrated with standard potassium hydroxide solution in ethanol using as indicator Bromphenol blue. The results were used to calculate the number present unreacted Palmyra. The reaction continued for 160 minutes the Results are presented in table. 2 (see the end of the description).1. The amount of Zr or Ti in parts per million relative to the weight of ester.2. The units of turbidity. Color of the final reaction mixture.3. The catalyst Ti(OiPr)4added in a 10 ml solution in 2-ethylhexanol.4. After a reaction time of at least 160 minutesExample 7.To obtain polyethylenterephthalat (PET) used the products of examples 3, 4 and 5. In jacketed reactors loaded glycol (26 l) and terephthalic acid (60,5 kg). Added catalyst and other additives, and to initiate the first stage of the process of direct esterification (DE) the reactor was heated to the temperature 226-252oC. After completion of the reaction DE (direct esterification) the contents of the reactor were transferred to the autoclave with stirrer. Added stabilizers and catalysator (Sb2O3) and the mixture to remove ethylene glycol and gaining the nl. 3 (see the end of the description).1. The amount of Zr or Ti in parts per million relative to the final weight of PET (polyethylene terephthalate).2. The value of b (yellowing) on the color scale CIE Lh, ahand bh.Example 8.For carrying out reactions polyesterification usually add phosphate stabilizers, but it is known that they at least partially inactivate titanium catalysts. The following example illustrates that the catalyst used in this invention are more resistant to deactivation than the conventional catalyst, such as tetraisopropoxide.Repeating example 6, except that before adding the catalyst to the reaction mixture was added phosphoric acid.The results are presented in table. 4 (see the end of the description).Example 9.For the production of polyethylene terephthalate used the product of example 5, with terephthalic acid were downloaded periodically. The capacity for the reaction downloaded 2250 kg of terephthalic acid and 1050 l of ethylene glycol, 50 frequent. a million NaOH and 1920 frequent. per million solution of catalyst 5(80 frequent. per million atoms of Ti relative to potentially vozmojnos is 55 ppm of the stabilizer, which was phosphoric acid, and the reaction mixture was transferred to the autoclave.Added 300 frequent. a million acetate tetrahydrate cobalt, the reaction mixture is heated to a temperature of 295oC and carried out the polymerization under vacuum. The final complex polyester had a characteristic viscosity 0,685 (viscosity solution of about 8% solution of a complex of the polyester in o-chlorophenol at 25oC) was transparent as glass, and had no signs of turbidity of the catalyst. Extrudable sheet obtained above complex of the polyester was extrudible in the usual way from the head of the extruder on the polished surface of a cooled rotating drum on which sheet is sharply cooled to a temperature below the glass transition temperature of the complex of the polyester, thus amorphous film. The hardened film is then re-heated, stretched in the direction of the extruder 3.2 times relative to its original length, pass through the furnace of Stenter and the sheet was stretched in the transverse direction approximately 3.8 times compared to its first size, and then realized the heat setting. The final thickness was 125 micrometers. Large angle opacity of the film amounted to 0.51 percent.When vicepresidential (40 ppm of Ti atoms) in an amount of 250 parts per million, large angle of turbidity obtained film was 1.35 per cent.Example 10.For the production of polyethylene terephthalate used the product of example 5, it was used the method of polymerization in the melt as described in example 9. The obtained polymer had a characteristic viscosity 0,685 (viscosity solution of about 8% solution of a complex of the polyester in o-chlorophenol at 25oC) was transparent and had no signs of turbidity of the catalyst.750 g of the polymer obtained above was then polymerizable in a solid state at 213oC under a stream of nitrogen, but received a polymer of polyethylene terephthalate having a characteristic viscosity of 0.82, measured with viscosity of the melt. The rate of polymerization in the solid state with the use of the catalyst of example 5 was significantly higher than the rate achieved using the standard catalyst of antimony trioxide. The value of the characteristic viscosity, a measure of the rate of polymerization) increased 0,027 units/hour, while when using antimony trioxide is the characteristic viscosity was of 0.015 units/ hour.The final polymer using blow molding under pressure is conducting the esterification reaction in the presence of a catalyst, characterized in that the use of a catalyst which is a reaction product of artefiera or condensed orthoevra titanium or zirconium and alcohol containing at least two hydroxyl group of 2-hydroxycarboxylic acids and bases.2. The method according to p. 1, characterized in that Ortofon has the formula
where M is titanium or zirconium;
R is an alkyl group containing from 1 to 6 carbon atoms.3. The method according to p. 1, characterized in that the condensed Ortofon has the formula
where R1is an alkyl group containing from 1 to 6 carbon atoms;
M is titanium or zirconium;
n is preferably less than 20.4. The method according to p. 3, characterized in that n is less than 10.5. The method according to any of paragraphs. 1-4, characterized in that the alcohol containing at least two hydroxyl groups, is a diatomic alcohol.6. The method according to p. 5, characterized in that use is from 2 to 12 moles of a diatomic alcohol per 1 mole of titanium or zirconium.7. The method according to any of paragraphs. 1-6, characterized in that 2-oxicology is m-7, characterized in that use is from 1 to 4 moles of 2-hydroxy acid to 1 mol of titanium or zirconium.9. The method according to any of paragraphs. 1-8, characterized in that the base is sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium carbonate, magnesium hydroxide or ammonia.10. The method according to any of paragraphs. 1-9, characterized in that the catalyst is obtained from monobasic 2-hydroxycarboxylic acid and base are used in amounts comprising from 0.8 to 1.2 mole of base per 1 mole of the 2-hydroxycarboxylic acid.11. The method according to any of paragraphs. 1-9, characterized in that the catalyst is obtained from trehosnovnoy 2-hydroxycarboxylic acid and base are used in amounts of 1 to 3 moles of base per 1 mole of the 2-hydroxycarboxylic acid.12. The method according to any of the preceding paragraphs, characterized in that the use of 1 to 12 moles of base per 1 mole of titanium or zirconium.13. The method according to any of paragraphs. 1-12, characterized in that the catalyst contains water and has a pH in the range from 6 to 8.14. The method according to any of paragraphs. 1-13, characterized in that the esterification reaction involves the interaction of alcohol with stearic acid, ezoterikovou acid, capric acid, KAPRO is the benzoic acid, methylbenzoic acid, salicylic acid, phthalic acid, isophthalic acid, terephthalic acid, sabatinovka acid, adipic acid, azelaic acid, succinic acid, fumaric acid, maleic acid, naphthaleneboronic acid, pambou acid, trimellitic acid, citric acid, criminology acid or pyromellitic acid.15. The method according to any of paragraphs. 1-13, characterized in that the esterification reaction involves the interaction of alcohol with the anhydride of dicarboxylic acid or tricarboxylic acid.16. The method according to any of paragraphs. 1-13, characterized in that the reaction of esterification involves the complex interaction of the methyl ester, complex ethyl ester or complex propyl ester of acrylic acid or methacrylic acid with alcohol.17. The method according to any of paragraphs. 1-9, characterized in that the esterification reaction involves the interaction of two esters with getting the other two esters by sharing CNS groups.18. The method according to any of paragraphs. 1-9, characterized in that the esterification reaction involves reacting terephthalic acid or dimethyl terephthalate with 1,2-elandspoort according to any one of paragraphs. 1-17, characterized in that the catalyst is present in an amount of from 30 to 1000 ppm in terms of parts by weight of titanium or zirconium relative to the weight of ester obtained.20. The method according to any of paragraphs. 1-9, characterized in that the esterification is polyesterification and the catalyst is present in an amount of from 5 to 500 ppm in terms of parts by weight of titanium or zirconium relative to the weight of the obtained complex of the polyester.
CH2=CHC(CH3)2CH2CO2R (1), where R is alkyl WITH1-C2
FIELD: organic chemistry, chemical technology.
SUBSTANCE: invention relates to a method for preparing β-(4-hydroxy-3,5-di-tert.-butylphenyl)-propionic acid esters that are used in industry of polymers as stabilizing agents. Method involves carrying out the process of the ester interchange reaction of β-(4-hydroxy-3,5-di-tert.-butylphenyl)-propionic acid methyl ester with polyhydric alcohols in inert gas flow at enhanced temperatures (130-190°C in the presence of the following components, wt.-%: 2,6-di-tert.-butylphenolate sodium, 1.5-3.6; 4-(β-methylcaboxyethyl)-2,6-di-tert.-butylphenolate sodium, 4.0-8.6; sodium acrylate, 2.1-6.4; 2,6-di-tert.-butylphenol, the balance. Indicated compounds of alkaline metal are used in the amount 0.4-5.1 wt.-% of the amount of β-(4-hydroxy-3,5-di-tert.-butylphenyl)-propionic acid methyl ester as measure for the sum of 4-(β-methylcarboxyethyl)-2,6-di-tert.-butylphenolate sodium, alkaline metal 2,6-di-tert.-butylphenolate and sodium acrylate. Invention provides increasing yield of the end product and its enhanced quality.
EFFECT: improved preparing method.
2 cl, 1 tbl, 10 ex
FIELD: organic chemistry, chemical technology.
SUBSTANCE: invention relates to a method for preparing β-(4-hydroxy-3,5-di-tert.-butylphenyl)propionic acid esters that are used in polymeric industry as stabilizing agents. Method is carried out by the re-esterification reaction of β-(4-hydroxy-3,5-di-tert.-butylphenyl)propionic acid methyl ester with polyhydric alcohols at enhanced temperatures (130-190°C) in the inert gas flow in the presence of catalyst comprising the following components, wt.-%: sodium 4-(β-methylcarboxyethyl)-2,6-di-tert.-butylphenolate, 30.0-45.5, and sodium aluminate, 54.5-70.0. Indicated compounds of alkaline metal are used in the amount 0.7-6.0 mole% of the amount of β-hydroxy-3,5-di-tert.-butylphenol)propionic acid methyl ester. Invention provides enhancing yield and improving color index, reducing cost of the process and reducing amount of by-side products formed.
EFFECT: improved preparing method.
2 cl, 1 tbl, 10 ex
FIELD: chemical technology.
SUBSTANCE: invention relates to the improved method for re-esterification of fat and/or oil of biological origin by alcoholysis. Method involves preparing fat and/or oil of biological origin for re-esterification process in suitable capacity followed by alcoholysis by addition of monoatomic alcanol and catalyst to the prepared fat and/or oil. Amino acid or derivative of amino acid metallic salt insoluble in monoatomic alcanols is used as a catalyst. Also, invention relates to fatty acid monoesters preparing by indicated method that are used as diesel fuel. This simple method provides preparing the end product with high yield that is not contaminated with catalytic material impurities.
EFFECT: improved method for re-esterification.
19 cl, 28 ex