Wang Xuxu, Hu Xuebin, Zhao Chun, Sun Zhihua, Zheng Huaili, Li Junfeng, Wang Zhaoyang
State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China and Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China E-mail:
College of Water Conservancy and Architectural Engineering, Shihezi University, Shihezi 832002, China.
Water Sci Technol. 2019 Mar;79(6):1195-1205. doi: 10.2166/wst.2019.117.
In this study, powder activated carbon (PAC) utilized to activate peroxydisulfate (PDS) was investigated for decolorization of Acid Orange 7 (AO7). The results indicated a remarkable synergistic effect in the PAC/PDS system. The effect of PAC, PDS dosages and initial pH on AO7 decolorization were studied and the processes followed first-order kinetics. Response surface method with central composite design (CCD) model was utilized to optimize these three factors and analyze the combined interaction. The optimum condition for the decolorization rate of AO7 was analyzed as the following: PAC (0.19 g/L), PDS (1.64 g/L), and initial pH (4.14). Cl and SO showed a promoting effect on AO7 decolorization while HCO had a slightly inhibiting effect. Quenching experiments confirmed that both sulfate and hydroxyl radicals were the oxidizing species, and the oxidation reaction occurred on the surface of PAC. The results of UV-vis spectrum with 100% decolorization rate and the 50% total organic carbon reduction indicated highly efficient decolorization and mineralization of AO7 in the PAC/PDS system. Finally, the recovery performance of PAC was studied and the result indicated PAC had poor reuse in reactivity.
在本研究中，对用于活化过二硫酸盐（PDS）的粉末活性炭（PAC）进行了酸性橙7（AO7）脱色研究。结果表明，PAC/PDS体系具有显著的协同效应。研究了PAC、PDS投加量和初始pH值对AO7脱色的影响，该过程符合一级动力学。采用中心复合设计（CCD）模型的响应面法对这三个因素进行优化并分析其联合相互作用。AO7脱色率的最佳条件分析如下：PAC（0.19 g/L）、PDS（1.64 g/L）和初始pH值（4.14）。Cl和SO 对AO7脱色有促进作用，而HCO 有轻微抑制作用。猝灭实验证实，硫酸根自由基和羟基自由基均为氧化物种，氧化反应发生在PAC表面。100%脱色率和50%总有机碳减少的紫外可见光谱结果表明，PAC/PDS体系中AO7具有高效脱色和矿化效果。最后，研究了PAC的回收性能，结果表明PAC的反应活性回用性较差。
