The catalytic reduction-oxidation collaborative processes for enhanced elimination of TBBPA over Pd/CeO2-R catalyst

Abstract

The degradation of tetrabromobisphenol A (TBBPA) was inhibited due to the existence of strong electron attraction Br. The reduction of TBBPA usually generated bisphenol A (BPA), which still do harm to the environment. Herein, we prepared Pd/CeO2 catalysts for the valid elimination of TBBPA with clean products via the catalytic hydrodebromination-oxidation (R-O) synergy processes. TBBPA suffered debromination and BPA and Br- were the products after reaction for 60min during the catalytic hydrodebromination (HDBr) processes, BPA could be degraded smoothly in the following oxidation step involved PMS activation, reflecting an excellent ability of the Pd based catalyst for the activation of H2, C-Br bond and PMS. Both Pd0 and Pdn+ played key roles for the HDBr of TBBPA, while Pd0 was the main active sites for the oxidation of BPA. HOBr generated from Br- oxidation favored the removal of BPA while the reactive species such as 1O2 generated from PMS activation further accelerated the TOC removal. The TOC removal rate was 5.2% for the direct degradation of TBBPA in the PMS/DP-Pd/CeO2-R system, while this value increased to 57.5% in the R-O synergy system. In addition, after reaction for 120min to eliminate TBBPA, the products were friendly to the aquatic organisms in the R-O synergy system, while the products remain exhibited strong toxicity in the single oxidation system, highlighting the advantages of the Pd/CeO2 catalyst triggered reduction/oxidation cooperation processes.