Catalytic Hydrodechlorination of trichloroethylene by Anion Exchange Resin Supported Palladium Catalysts

Abstract

A new class of supported palladium catalyst with high metal content was developed and used for catalytic hydrodechlorination of trichloroethylene in water. The palladium catalyst was prepared successfully by a simple and straightforward way using two commercial strong base anion (SBA) exchange resins (Amberlite IRA-900 and Amberlite IRA-958) as catalyst carrier. Batch kinetic experiments demonstrated that at an catalyst dose of 1 g/L with palladium content of 17 wt% , the trichloroethylene in the system was degraded within 2 hours at ambient temperature. For the IRA-900 supported Pd catalysts, the apparent kinetic constant (kapp) increased from 0.0400 min-1 to 0.2651 min-1 as Pd loading increased from 13.6 to 39.0 wt%. For the IRA-958 supported Pd, the rate constant increased from 0.0470 min-1 to 0.2344 min-1 as Pd loading increased from 11.0 to 33.0 wt%. At the end of the reaction, the catalysts remain active and can be repeatedly used in multiple cycles of treatment without reactivity loss. IRA-900 supported Pd catalysts offered better catalytic activity with DOM concentration of 3 mg/L and 10 mg/L. This kind of SBA resin supported Pd catalysts may serve as a class of effective catalysts in water treatment.