(1. 昆明理工大学 环境科学与工程学院,昆明 650500;
2. 天津市水利科学研究院 水环境研究所,天津 300061)
摘 要: 采用脉冲电催化内电解流化床技术同时去除浮选废水中的Pb2+和苯胺黑药,运用序批试验和SEM、XPS等分析研究影响污染物去除的工艺条件、脉冲电催化效应、Pb2+和苯胺黑药的去除或降解机制。结果表明:当pH为4、电流密度为20 mA/cm2、脉冲周期为2 s、停留时间为90 min时,Pb2+和苯胺黑药的去除率分别为99.80%和78.83%,BOD5/CODCr值由0.15上升至0.41。该技术能较好地同时去除浮选废水中的Pb2+和苯胺黑药,显著提高废水的可生化性。Pb2+和苯胺黑药的去除得益于脉冲电催化内电解体系下的氧化还原反应、电沉积和高聚合度铁氢氧化物的絮凝沉淀作用等;苯胺黑药在新生态Fe2+、[H]、H2O2、?OH等活性物质的作用下先后脱除二硫代磷酸基、脱氨基、苯环开环断裂而被降解为有机小分子和无机物。
关键字: 浮选废水;铅;苯胺黑药;脉冲电催化;内电解;流化床
(1. Faculty of Environmental Science and Technology, Kunming University of Science and Technology,
Kunming 650500, China;
2. Institute of Environment and Water Research, Tianjin Hydraulic Science Research Institute, Tianjin 300061, China)
Abstract:Pulsed electro-catalytic internal micro-electrolysis fluidized bed (PEIMEF) was used for simultaneous removal of Pb2+ and dianilino dithiophosphoric acid (DDA) from flotation wastewater. Sequencing batch tests and SEM, XPS were conducted to investigate the process conditions, the effect of pulsed electro-catalytic and removal mechanism. The results show that the removal efficiency of Pb2+ and DDA are 99.80% and 78.83%, respectively, and BOD5/CODCr increases to 0.41 from 0.15 at pH of 4, current density of 20 mA/cm2, pulse time of 2 s and hydraulic retention time of 90 min. PEIMEF can removes Pb2+ and DDA well, and improve the biodegradability significantly. The removal of Pb2+ and DDA is due to the redox reaction, electro-deposition and flocculation precipitation of iron hydroxide of high degree of polymerization under the function of PEIMEF. The degradation of DDA to small organic molecule and inorganic substance may be attributed to the repture of dithiophosphate groups, deamination and ring opening of benzene ring successively by the catalytic redox of the generated active substances of Fe2+, [H], H2O2, ?OH.
Key words: flotation wastewater; lead; dianilino dithiophosphoric acid; pulsed electro-catalysis; internal micro- electrolysis; fluidized bed