Removal of Selenium (VI) from Simulated Wet Flue Gas Desulfurization Wastewater Using Photocatalytic Reduction

Abstract

The removal of Se(VI) from a simulated wet flue gas desulfurization (FGD) wastewater was attempted by the use of a photocatalytic reduction system. Conventional method of removal, such as adsorption by ion-exchange resins, was not effective for Se(VI) removal from wastewater. The photocatalyst reduction system consisted of TiO₂ and HCOOH as a photocatalyst and an electron hole scavenger, respectively. When the photo-irradiation was performed for a Se(VI) solution under the system, an efficient removal of Se(VI) was achieved, suggesting that the reduction of Se(VI) actually occurs via the photocatalytic system to produce Se(0) precipitate. The photocatalytic reduction system could be applied to Se(VI) removal from the simulated wastewater. However, excess amount of HCOOH was needed to achieve efficient Se(VI) removal from wastewater.