微量铜离子联合碳酸氢盐类芬顿体系降解水中双酚A

Degradation of bisphenol A by Fenton-like system using trace copper ions combined with bicarbonate in water

基于铜离子(Cu^(2+))的类芬顿体系通常需要较高的Cu^(2+)剂量,可能导致二次污染,为解决这一问题,构建了微量Cu^(2+)(2.5μmol/L)联合碳酸氢盐活化过氧化氢(Cu^(2+)/H_(2)O_(2)/HCO_(3)^(-))体系用于水中双酚A(BPA)的高效降解.结果表明:在一定范围内,Cu^(2+)/H_(2)O_(2)/HCO_(3)^(-)体系对BPA的降解效果随Cu^(2+)投加量的升高而上升,随H_(2)O_(2)和HCO_(3)^(-)投加量的升高呈先上升再降低的趋势.在溶液初始pH值5.06~11.02范围内,BPA均可得到有效去除,且升高反应温度可促进BPA的降解.Cl-、HPO_(4)^(2-)、腐殖酸会抑制BPA降解,而NO_(3)^(-)、SO_(4)^(2-)的影响则可以忽略不计.活性物种猝灭和捕获实验表明,单线态氧和Cu^(3+)是BPA降解过程的主要活性物种.CuCO_(3)(aq)可能是H_(2)O_(2)活化生成的活性氧化物种与Cu^(3+)的主要络合物.同时,Cu^(2+)/H_(2)O_(2)/HCO_(3)^(-)对天然水体基质中的BPA也有较好的去除效果.另外根据5种鉴定的中间体,提出了Cu^(2+)/H_(2)O_(2)/HCO_(3)^(-)体系中BPA的可能降解途径.

Higher Cu^(2+)dosage is typically needed for Fenton-like systems based on copper ions(Cu^(2+)), which could result in secondary pollution.In the current study, an effective system for degrading bisphenol A(BPA) was built using bicarbonate-activated hydrogen peroxide and trace copper ions(Cu^(2+)/H_(2)O_(2)/HCO_(3)^(-)).According to the findings, increasing the Cu^(2+)dosage boosted the removal efficiency of BPA, while increasing the H_(2)O_(2)or HCO_(3)^(-)dosage caused the trend to grow initially before declining.BPA can be effectively removed within the range of the initial pH value of solution 5.06~11.02, and the degradation efficiency was improved with increased temperature.The presence of Cl-、HPO_(4)^(2-)and humic acid(HA) were found to delayed the elimination of BPA, while other anions like NO_(3)^(-)and SO_(4)^(2-)had no obvious effects.Quenching and trapping experiments showed that the identified single oxygen and Cu^(3+)were the predominant reactive species responsible for BPA degradation.CuCO_(3)(aq) was the major complex with a high reactivity for H_(2)O_(2)activation to form reactive oxygen species(ROS) and Cu^(3+).At the same time, there is a good removal effect of BPA in the natural water matrix of the Cu^(2+)/H_(2)O_(2)/HCO_(3)^(-)system.In addition, the mechanism of possible degradation of BPA in Cu^(2+)/H_(2)O_(2)/HCO_(3)^(-)has been proposed from the five identified intermediates.