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 TiO 2 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.

Effect of Elevated Temperature on Ceramic Ultrafiltration of Colloidal Suspensions

“…A synthetic flue gas desulfurization (FGD) wastewater was developed and used in fouling experiments based off of the wastewater created in the studies by Nakajima et al [26]. Fouling experiments using this wastewater were to be used as a determinant of the applicability of ceramic membrane treatment at elevated temperatures for FGD wastewater in coal-fired power plants.…”

Photocatalytic removal of selenite and selenate species: effect of EDTA and other process variables

“…In this regard, an earlier work on TiO 2 photocatalytic reduction of selenium oxyanions was carried out by Kikuchi et al [23] Since then, these systems have been examined by several other groups. [24][25][26][27][28][29][30][31][32][33][34][35][36] Many of these studies have also investigated the role of hole (h + ) scavengers such as formic acid during TiO 2 -assisted photocatalytic reduction of selenite and selenate and report significant removal of selenium contamination from the aqueous phase. [24][25][26][27][28] Recently, Aman et al [36] also reported using a modified Ti-Zrbased photocatalyst and EDTA (as a hole scavenger) for selenite/selenate removal from the aqueous phase.…”

Flue Gas Desulfurization Wastewater Composition and Implications for Regulatory and Treatment Train Design

“…Existing work that tests emerging technologies for FGD wastewater treatment does not explicitly take into account intra- and interplant variability. Instead, much of the published literature that evaluates the efficacy of FGD wastewater treatment technologies tested process performance using grab samples collected from CFPPs , or synthetic wastewaters based on average concentrations reported in the literature. , Both approaches ignore the intra- and interplant variability found in sampling campaigns and our results. Instead, BAT performance should be demonstrated on the full range of characteristic feedwater concentrations.…”