纳米TiO_2薄膜对痕量Cu（Ⅱ）的吸附研究

摘要

TiO2 nano-film with homogeneous surface was prepared on the glass substrate by the sol-gel method.The film was characterized by SEM and XRD.The adsorption of trace Cu（Ⅱ） was carried out taking TiO2 nano-film as an adsorbent.The effects of pH values,adsorption time,initial concentrations of Cu（Ⅱ） and coexistent ions on the adsorption rates were studied systematically.The results showed that the film is composed of anatase TiO2 nanoparticles with the grain diameter about 50 nm.The adsorption isotherm of Cu（Ⅱ） on TiO2 nano-film shows ＂L＂ type,which is explained by the monolayer adsorption.The Cu（Ⅱ） adsorbed on TiO2 nano-film is eluted by 1.0 mol/L nitric acid efficiently.The optimum adsorption conditions are determined.%应用溶胶-凝胶法,以玻璃为基底,制备了表面结构均匀的纳米TiO2薄膜.SEM和XRD分析结果表明,TiO2薄膜由粒径50 nm左右的锐钛矿TiO2颗粒构成.利用纳米TiO2的表面吸附活性,系统研究了纳米TiO2薄膜对于水中痕量Cu（Ⅱ）的吸附活性.探讨了溶液的pH值、吸附时间、Cu（Ⅱ）初始质量浓度对纳米TiO2薄膜吸附率的影响,确定了最佳吸附条件.纳米TiO2薄膜对Cu（Ⅱ）的吸附等温线为＂L＂型,表现出单分子层吸附特征.1.0 mol/L硝酸可将吸附在薄膜表面的Cu（Ⅱ）洗脱.