METHOD OF PREPARING ESTERS OF TEREPHTHALIC ACID

The present invention relates to the field of preparing esters of terephthalic acid, used as plasticizers for the manufacture of plasticizers for polyvinyl chloride plastic materials. The invention discloses a method according to which the step of esterification of the acid with an alcohol comprises the use of two catalysts of different nature, in particular a metal-containing catalyst and an acidcatalyst, which are added sequentially. The technical result of the present invention is to increase conversion of terephthalic acid up to 100% and to reduce the amount of by-products formed during the production of a dicarboxylic acid ester. The obtained ester is characterized by a low acid number and a low value of color. 本发明涉及制备对苯二甲酸的酯的领域，所述对苯二甲酸的酯用作用于制造聚氯乙烯塑料材料用增塑剂的增塑剂。本发明公开了这样的方法：根据所述方法，酸与醇的酯化步骤包括使用两种不同性质的催化剂，特别是顺序添加的含金属催化剂和酸催化剂。本发明的技术结果是将对苯二甲酸的转化率提高至100％，并且减少在二羧酸酯的生产期间形成的副产物的量。所获得的酯的特征在于低酸值和低色度值。