RECOVERY ORGANIC ACID AS METHOD OF SYNTHETIC PYRETHROID

摘要

This is for recovery of high cost organic acid in production of synthetic pyrethroide of α-cyano ester type. The method comprises: (A) oxidized decomposition NaCN by treating water layer that has NaCN and organic acid with hydrogen peroxide; (B) after acidifing solution, separation and recovery of unreacted organic acid. The oxidized decomposition process is done at pH 10.5-11.0 and 40-60 deg.C. An amount of used hydrogen peroxide is 1.0-2.0 eq. based on 1 eq. of NaCN.