利用蒸汽加压混凝土废料去除废水中的Cd(Ⅱ)

Removal of Cd(Ⅱ) from Wastewater by Autoclaved Aerated Concrete Waste

文中以蒸汽加压混凝土(AAC)废料研磨加工的粉末作为吸附剂,研究AAC废料对含Cd^(2+)废水的去除效果及其机理.通过X射线荧光光谱(XRF),扫描电子显微镜(SEM),X-射线衍射分析(XRD)手段表征AAC的结构与物理性质,并研究该材料在不同反应条件下对低质量浓度(3 mg/L)Cd^(2+)的吸附性能.结果表明:当AAC投加质量浓度为10 g/L时,吸附90 min后Cd^(2+)的去除率可达到97%;吸附反应符合Langmuir方程和拟二级动力学方程,且在吸附过程中同时存在物理吸附和化学吸附机理.此外,AAC对工业污水中Cu^(2+)、Pb^(2+)和Zn^(2+)等其它重金属离子表现出广泛的去除效果.建筑行业AAC废料可有效去除水溶液中的有毒重金属离子.因此,AAC是一种低成本、具有应用前景的净水剂.

The removal efficiency and mechanism of Cd2＋in wastewater were studied by using the powder of autoclaved aerated concrete（ AAC） waste. The structure and physical properties of AAC were characterized by XRF,SEM,XRD and its adsorption properties for removal of 3 mg/L Cd2＋under different conditions were investigated.The results showed that the removal rate of AAC for Cd2＋has attained 97% after 90 min when the initial dosage of AAC was 10 g/L. The adsorption process fitted to Langmuir model and pseudo-second-order kinetic model. Physical adsorption and chemisorption were both observed during the process. Besides,AAC possesses comprehensive removal effect for other heavy metal ions including Cu2＋,Pb2＋and Zn2＋in industrial wastewater. AAC of the construction industry can effectively remove the toxic heavy metal ions in the aqueous solution and is a low cost and promising water purifying agent.