METHOD OF RECIRCULATION OF CATALYST IN PROCESSES OF DIRECT OXIDATION OF CYCLOHEXANE TO ADIPIC ACID Russian patent published in 2000 - IPC

FIELD: chemical industry. SUBSTANCE: described is method of recirculation of cobalt-containing catalyst in processes of direct oxidation of cyclohexane to adipic acid with oxygen-containing gas. Reaction mixture resulting from previous oxidation of cyclohexane to adipic acid at least part of which includes intermediate products is treated to remove highly volatile compounds after possible crystallization and separation of at least part of adipic acid contained therein, the resulting residue is treated for extraction of at least part of glutaric and succinic acid formed in the course of oxidation reaction, and residue containing greatest part of cobalt catalyst is used for oxidation to adipic acid at new stage. EFFECT: recirculation of cobalt catalyst when it loses activity insignificantly or completely. 23 cl, 8 ex, 5 tbl