METHOD OF PRODUCING N-2-ETHYLHEXYL-N'-PHENYL-p-PHENYLENEDIAMINE Russian patent published in 2012 - IPC C07C211/51 C07C211/55 C07C209/16 

FIELD: chemistry.

SUBSTANCE: invention relates to an improved method of producing N-2-ethylhexyl-N'-phenyl-p-phenylenediamine by reacting p-aminodiphenylamine with 2-ethylhexanol in the presence of potassium hydroxide, at temperature 170-235°C with simultaneous distillation of the alcohol azeotrope with water through a heated refluxer and returning the condensed hot alcohol into the reaction zone, separating the end product from the organic layer after aqueous extraction. The mixture of 2-ethylhexanol and potassium hydroxide is preheated to 90-140°C fed into the reaction mass in two steps, at the first step at temperature of the p-aminodiphenylamine not lower than 100°C, 50-90 wt % of the calculated amount of the mixture of 2-ethylhexanol and potassium hydroxide is fed, and the remaining amount is continuously fed until temperature of the reaction mass reaches 200-235°C.

EFFECT: method cuts the duration of the alkylation step and increases efficiency of the equipment.

1 tbl, 9 ex