REMOVAL OF SALICYLIC ACID BY CATALYTIC WET OXIDATION PROCESS USING PEROVSKITE TYPE OXIDE CATALYSTS

Abstract

The removal of salicylic acid from waste water by catalytic wet air oxidation (CWAO) process using perovskite type oxide LaFeO3 catalyst gives efficient results at the lower temperatures of 140C. The conversion of salicylic acid was also done by the CWAO on La 203 and Fe203 catalysts, and the results compared with the activities on all the three catalysts. The conversion percentage on LaFe03 is very high as compared to the La203 and Fe203 because of its intramolecular H-bonding structure. Due to the presence of high acidity of intramolecular Hbonding the basic center of LaFe03 catalysts adsorbed salicylic acid effectively and the total oxidation reactions took place. As temperature was raised above 140C, the intramolecular Hbonding of salicylic acid destroyed, which indicate the key role of intramolecular H-bonding in catalytic wet air oxidation process. Moreover, the perovskite type oxide LaFe03 catalyst also indicated the greater stability in the catalytic wet air oxidation (CWAO) process of salicylic acid