纳米γ-Al_2O_3对Ag(Ⅰ)及其配合物的吸附性能表征

Adsorption Behaviors and Characterization of Nanometer γ-Al_2O_3 Powders to Ag(Ⅰ) and its Complex

溶胶-凝胶法合成纳米γ-Al2O3，以透射电镜（TEM）、X射线衍射（XRD）、比表面积测定（BET）等手段对所得的纳米γ-Al2O3进行了表征，表明纳米粒子的直径在10～50nm．并利用Zetaplus电位仪测定了其等电点为7．65．考察了纳米γ-Al2O3。在静态吸附条件下对Ag（Ⅰ）及其配合物的吸附性能．结果表明，在pH值分别为5～6．5，8～9，2．5～9时，对Ag^＋，Ag（NH3）2^＋，Ag（S2O3）2^3-的吸附能力最强，且符合Freundlich吸附方程．吸附于纳米γ-Al2O3上的Ag（Ⅰ）及其配合物离子，可用0．1mol·L^-1HNO3溶液进行解脱，再生后的纳米γ-Al2O3吸附能力基本不变．

The nanometer γ-Al2O3 powders are synthesized by Sol-Gel method, and characterized by TEM, XRD, BET and Zeta potential measurement. It is found that their diameters are between 10 nm to 50 nm. The adsorption characterization of Ag（ Ⅰ ） and its complex on the powders in static condition is explored. It showed that the powders have strong adsorption capacity for Ag^＋ ,Ag（NH3）2^＋ , Ag（S2O3）2^3- at a given pH value at 5-6.5, 8-9, 2.5-9 and the adsorption process o[ Ag^＋ ,Ag （NH3）2^＋ , Ag（S2O3）2^3- on powders comply with Freundlieh adsorption model. The adsorbed metallic ions on the powders can be desorbed in 0.1 mol.L^-1 HNO3 solution, and the regenerated powders have the same adsorption capacity.