Regeneration of Adsorbents Using Heterogeneous Photocatalytic Oxidation

Abstract

The overall objective of this study is to investigate the technical feasibility of removal and destruction of organic contaminants in water using adsorption and photocatalytic oxidation. The process consists of two consecutive operational steps: (1) removal of organic contaminants using fixed-bed adsorption; and (2) regeneration of the spent adsorbent using photocatalytic regeneration. To facilitate the regeneration, some of the adsorbents were impregnated with photocatalysts, which would allow them to act as both an adsorbent for capturing the organics and a photocatalyst for destroying the organics during regeneration. Laboratory-scale adsorption processes were conducted using rapid small-scale column tests (RSSCTs) for the loading of F-400 GAC (60X80) and Ambersorb 563 (60X80) with trichloroethene (TCE) and para-dichlorobenzene (p-DCB), respectively. The spent adsorbents were regenerated in a plate photoreactor and the organic-free water was used. For the impregnated F-400 carbon, catalyst loading was observed to have little impact on the adsorption capacity for TCE. The Pt-TiO