AN INTEGRATED PROCESS FOR THE PRODUCTION OF 2,6-NAPHTHALENE DICARBOXYLIC ACID

摘要

Disclosed is an integrated process for producing 2,6-naphthalene dicarboxyli c acid comprising oxidizing a methylnaphthalene feedstock, hydrodebrominating the crude naphthoic acid product under conditions different from any work known in the art, forming a potassium salt of the acid; disproportionating t he potassium salt to produce 2,6 potassium salts of NDA; selectively precipitating K2NDA; selectively precipitating the monopotassium salt of 2,6 - NDA(KHNDA); disproportionating the KHNDA into 2,6-NDA and K2NDA; further reacting the 2,6-NDA in a pipe reactor; and drying the product 2,6-NDA by conventional means or directly slurrying directly into a PEN process. The process can tolerate impurities in the economical methylnaphthalene feed and the resulting 2,6-NDA is of high quality with <50 ppm potassium.