黄铜矿活化过硫酸盐处理丁基黄药废水的研究

Treatment of Butyl Xanthate Wastewater with Chalcopyrite Activated Persulfate

以天然黄铜矿(CuFeS_(2))作为催化剂活化过硫酸盐(PS)处理丁基黄药废水,考察了CuFeS_(2)用量、PS用量和溶液初始pH值对CuFeS_(2)/PS体系中丁基黄药去除率的影响,并对CuFeS_(2)可重复利用性进行了评价。结果表明,CuFeS_(2)对PS有显著的活化作用,在CuFeS_(2)用量4 g/L、PS用量5 mmol/L、溶液初始pH=3条件下反应10 min,丁基黄药去除率达99.23%,TOC去除率仅31.29%;继续增加反应时间至60 min, TOC去除率达到68.31%,且CuFeS_(2)重复利用5次后仍有较好的催化活性。丁基黄药废水降解过程的紫外-可见吸收光谱研究结果表明,丁基黄药首先被氧化为醇类有机物,后被分解矿化为二氧化碳和水。XRD和FTIR分析结果表明,CuFeS_(2)与PS反应后表面没有发生钝化,可重复利用。自由基猝灭试验和电子自旋共振分析(ESR)结果表明,黄药的去除机理包括自由基的化学降解作用和CuFeS_(2)的物理吸附作用,其中,硫酸根自由基(SO_(4)^(-)·)和羟基自由基(HO·)是促使黄药降解的主要活性物质,且SO_(4)^(-)·起主导作用。

Natural chalcopyrite(CuFeS_(2))was used as a catalyst to activate persulfate(PS)for butyl xanthate wastewater treatment.The influences of CuFeS_(2) dosage,PS dosage and initial pH of solution on the removal rate of butyl xanthate in CuFeS_(2)/PS system were investigated,and the recyclability of CuFeS_(2) was also evaluated.The results show that CuFeS_(2) can significantly activate PS.After 10 min reaction with initial pH of 3,CuFeS_(2) dosage of 4 g/L and PS dosage of 5 mmol/L,the removal rate of butyl xanthate reached 99.23%,while the removal rate of total organic carbon(TOC)was only 31.29%.After the reaction time was extended to 60 min,the TOC removal rate reached 68.31%,and CuFeS_(2) still sustained good catalytic activity after being recycled for five times.The UV⁃Visible absorption spectra of butyl xanthate wastewater degradation showed that butyl xanthate was initially oxidized to alcohols,then decomposed and mineralized to carbon dioxide and water.X⁃ray diffraction and fourier transform infra⁃red spectroscopy analysis showed that CuFeS_(2) reacted with PS without surface passivation,thus could be reused.A free radical quenching test and an electron spin resonance analysis showed that the removal mechanism of xanthate included free radical degradation and CuFeS_(2) physisorption,in which sulfate radical(SO_(4)^(-)·)and hydroxyl radical(HO·)were the main active substances to promote xanthate degradation,and the SO_(4)^(-)·played a dominant role.