FIELD: chemistry.
SUBSTANCE: invention relates to the method for producing carboxylic acid esters, in which in the reaction system consisting of one or more reactors, the reaction mixture is subjected to the interaction, which contains, at least, one carboxylic acid and/or, at least, one anhydride of carboxylic acid and, at least, one alcohol R1-OH and/or, at least, one alcohol R2-[O-X]n-OH, where R1 is selected from among the unbranched and branched alkyl residues with 5 to 13 carbon atoms and the cycloalkyl residues with 5-6 carbon atoms, wherein the cycloalkyl residues are unsubstituted or may be substituted by, at least, one alkyl residue with 1-10 carbon atoms, R2 is selected from among the unbranched alkyl residues with 1-13 carbon atoms and the branched alkyl residues with 3-13 carbon atoms, X represents an unbranched alkylene group with 2-5 carbon atoms or a branched alkylene group with 3-5 carbon atoms, and n has a value of 1, 2 or 3, provided that the interaction is carried out in the presence of, at least, one catalyst selected among methansulfonate acid and toluene sulphonic acid, wherein methansulfonate acid has a sulfate content not exceeding 50 ppm, and wherein toluene sulphonic acid has a sulfate content less than 0.3%, when feeding gas being inert under the reaction conditions to the reaction system, at the temperature of the reaction mixture of 125 to 240°C, and when separating by distillation of, at least, a part of water produced during the reaction in the form of an azeotropic mixture with the used alcohol R1-OH and/or R2-[O-X]n, wherein distilled alcohol R1-OH and/or R2-[O-X]n-OH is, at least, partially recycled to the reaction system.
EFFECT: improved method for producing carboxylic acid esters, allowing a more complete conversion after a short reaction time, and therefore a high yield of time unit per volume unit, the method is technically simple, carried out by using an inexpensive catalyst and avoiding costly processing steps.
17 cl, 1 dwg, 19 ex
