联合改性污泥吸附剂去除废水中铬(Ⅵ)  

Removal of Cr(Ⅵ) from wastewater by sludge-based adsorbents with combined modification

作　　者：刘蕾 付临汝 杜馨 张立国[2] 吴宏海[2] 肖羽堂[2] LIU Lei;FU Linru;DU Xin;ZHANG Liguo;WU Honghai;XIAO Yutang(School of Environment and Civil Engineering,Dongguan University of Technology,Dongguan,523808,China;School of Chemistry and Environment.South China Normal University,Guangzhou,510006,China;Guanzhou Municipal Vocational College,Guangzhou,510500,China)

机构地区：[1]东莞理工学院,生态环境与建筑工程学院,东莞523808 [2]华南师范大学,化学与环境学院,广州510006 [3]广州市市政职业学校,广州510500

出　　处：《环境化学》2018年第12期2596-2602,共7页Environmental Chemistry

基　　金：国家自然科学基金(41372050);广东省自然科学基金(2016A030313432);广东省高校优秀青年创新人才培养计划资助项目(2012LYM_0050);广东高校化工清洁生产与绿色化学品工程技术开发中心项目(201405)资助.

摘　　要：以城市污水厂脱水污泥为原料,分别经物理活化、物理与化学活化相结合的方法制备污泥基吸附剂样品,通过BET表面积分析、扫描电镜(SEM)、傅里叶红外光谱分析等对污泥吸附剂性质进行了表征,对比研究了不同改性方法制备的污泥基吸附剂对Cr(Ⅵ)的去除性能.结果表明,经过NaOH联合改性的污泥吸附剂W6对Cr(Ⅵ)吸附性能最好,其次为HNO_3联合改性的污泥吸附剂样品W4,污泥吸附剂去除Cr(Ⅵ)的最佳pH值为2.5.对于样品W4、W6来说,室温下(25℃)其吸附行为更符合Langmuir等温吸附模型,说明这两种吸附剂对Cr(Ⅵ)吸附都主要以单分子层形式吸附为主.改性污泥吸附剂样品均较适合准二级动力学模型,其相关系数均达到了0.99以上.因此,物理与化学联合改性方法可以显著改善污泥吸附剂对Cr(Ⅵ)的吸附性能.Dewatered sludge from a municipal wastewater treatment plant (WWTP)was used to prepare sludge-based adsorbents (SBAs)by means of physical activation,and the combination of physical and chemical activation with the addition of foaming agent.The SBA samples were characterized using BET surface area analysis,scanning electron microscopy (SEM),FT-IR,and the effects of different modification methods on Cr (Ⅵ)removal efficiency were investigated comparatively.The results showed that the SBA sample (W6)by the combined modification with NaOH achieved the highest Cr(Ⅵ)removal rate,follewed by is the SBA sample (W4)by combined modification with HNO3.The optimum pH for Cr (Ⅵ )removal was 2.5.At 25℃,the Cr (Ⅵ )removal for SBA samples of W6 and W4 were well fitted with the Langmuir isotherm model,which indicated that monolayer adsorption was the main adsorption process.The adsorption kinetic data were well fitted with the pseudo second-order model for all SBA samples,and the correlation coefficients were all over 0.99.Therefore,the combination of physical activation and chemical activation for preparing SBAs can improve the adsorption properties for Cr(Ⅵ ).

关 键 词：污泥吸附剂 改性 吸附 Cr(Ⅵ) 

分 类 号：X703[环境科学与工程—环境工程]