Evaluation of Granular Surfactant-Modified/Zeolite Zero Valent Iron Pellets As a Reactive Material for Perchloroethylene Reduction

Abstract

The use of permeable reactive barriers (PRBs) for groundwater remediation is based on two distinct mechanisms: sorption and transformation. With sorption as the main mechanism, contaminants sorb on the PRB materials and are retarded. With transformation as the main mechanism, the contaminants react with the PRB materials and then converted to less toxic or innocuous substances. In this study, we tested surfactant-modified zeolite/zero valent iron (SMZ/ZVI) pellets as a PRB material to retard and degrade perchloroethylene (PCE), utilizing both sorption and transformation processes. Batch PCE kinetic studies showed instantaneous PCE removal from the aqueous phase due to sorption and subsequent removal with time due to reduction. The separation of sorption from reduction can be used to obtain both the PCE distribution coefficient ( Kd ) and the pseudofirst-order reduction rate constant ( μobs ) from a single batch experiment. The calculated Kd and μobs values are 3.0 and 0.5 L∕kg and 0.14 and 0.05 h−1 for SM...