METHOD OF PRODUCING N-2-ETHYLHEXYL-N'-PHENYL-N-PHENYLENEDIAMINE AND SEPARATING COMMERCIAL GRADE 2-ETHYLHEXANOIC ACID FROM WASTES FROM PRODUCTION OF N-2-ETHYHEXYL-N'-PHENYL-N-PHENYLENEDIAMINE Russian patent published in 2009 - IPC C07C211/51 C07C211/55 C07C209/16 

FIELD: chemistry.

SUBSTANCE: invention relates to an improved method of producing N-2-ethylhexyl-N'-phenyl n-phenylenediamine, which can be used as an antioxidant for polymers and separation of commercial 2-ethylhexanoic acid from wastes from production of N-2-ethylhexyl-N'-phenyl n-phenylenediamine, which is achieved through alkylation of n-aminodiphenylamine with 2-ethylhexanol at temperature ranging from 170 to 235°C with distillation of azeotropic alcohol with water, returning condensed hot alcohol to the reaction zone, separation of the desired product from the organic layer after aqueous extraction of the reaction mass. The alkylating agent used is an alcohol solution of potassium alcoholate, which is added continuously in uniform portions to molten n-aminodiphenylamine, preheated to temperature ranging from 210 to 230°C. Distillation of azeotropic alcohol with water is done using a fractional column in which temperature is kept between 90 and 110°C; the aqueous layer remaining after separation of the organic layer is treated with hydrochloric, sulphuric or phosphoric acid until pH between 2 and 4, the obtained mixture is divided into layers and 2-ethylhexanoic acid is extracted from the organic layer through vacuum distillation.

EFFECT: cutting on alkylation time, increased amine conversion, reduced specific consumption of alcohol, specific energy consumption, higher quality of desired product and obtaining end product from waste products.

5 cl, 8 ex, 1 tbl