盐亭膨润土的物化性能及对Pb^(2+)、Cd^(2+)的吸附研究

THE PHYSICOCHEMICAL PROPERTIES AND THE ADSORPTION OF BENTONITE IN YANTING TO Pb^(2+) AND Cd^(2+)

研究了四川盐亭膨润土的化学成分、阳离子交换容量、吸蓝量、比表面积、孔径等基本物化性能,以及时间、pH值、吸附剂用量、溶液浓度等因素对Pb2+、Cd2+吸附作用的影响。结果表明,矿石中蒙脱石含量为84%-93%,层间可交换阳离子主要为Ca2+,为钙基膨润土。该膨润土具有较好的阳离子交换性能,∑E为77.8~79.2mmol/100g,对溶液中的Pb2+、Cd2+有较好的吸附作用,且吸附速度快,在30min即可达到吸附平衡。吸附作用受溶液pH值影响明显。增加膨润土吸附剂添加量或加大溶液中金属离子浓度,均有利于提高膨润土对Pb2+、Cd2+的吸附总量。膨润土对Pb2+、Cd2+的吸附模式符合Frendlish方程。

The physicochemical properties of Ca-bentonite in Yanting, including chemical composition, the cationic exchange capacity, specific surface area, pore diameter and so on, and adsorption to Pb^2＋ and Cd^2＋ in solution. Have been studied in this paper. The study shows that ore have a continent of 90-95% bentonite. The exchangeable cationic between layer is main Cd^2＋ , and it is Ca-bentonite. The bentonite has a high cationic exchange capacity, ∑E 77.8-79.2meq/100g, and good adsorption to Pb^2＋ and Cd^2＋. Adsorption arrive equilibrium in 30min. and adsorption is affected by pH of solution. It is advantageous to adsorption of Pb^2＋ and Cd^2＋ when adsorbent or consistency of solution is increased. Adsorb model of bentonite to Pb^2＋ and Cd^2＋ is belong to Frendlish adsorption equation.