화학공학소재연구정보센터
Chemical Engineering Journal, Vol.294, 273-280, 2016
Comparing the efficacy of VUV and UVC/S2O82- advanced oxidation processes for degradation and mineralization of cyanide in wastewater
The present study was designed to evaluate cyanide degradation and mineralization in an industrial wastewater by vacuum ultraviolet (VUV) and ultraviolet/persulfate (UVC/S2O82-) advanced processes. The effect of operational conditions such as cyanide concentration, air/O-2 blowing, reaction time, S2O82- concentration, and presence of Cr(VI) were studied. The possible intermediates of the reaction were also tracked. It was observed that under optimal condition, complete destruction of 50 mg/L cyanide was reached in 15 min and 50 min for VUV-air and UVC/S2O82- processes, respectively. Tracking of the generated by-products revealed that VUV and UVC/S2O82- processes completely oxidized and mineralized cyanide to much less noxious compounds, mainly ammonia and carbonate. Application of VUV process for chromium electroplating wastewater (68 mg/L cyanide and 24 mg/L Cr(VI)) showed that complete oxidation of cyanide along with 72% reduction of Cr(VI) to Cr(III) was reached in a short reaction time of 18 min. Accordingly, the homogenous VUV advanced process was found to be an efficient chemical less method appropriate for simultaneous oxidation of cyanide and reduction of Cr(VI) in industrial wastewater. (C) 2016 Elsevier B.V. All rights reserved.