浮游球衣菌对Pb2+、Cu2+、Zn2+、Cd2+的吸附性能研究

研究了浮游球衣菌（Sphaerotilus natans）在不同吸附条件下对溶液中Pb^2＋、Cu^2＋、Zn^2＋、Cd^2＋的吸附规律。结果表明，Sphaerotilus natans对这4种重金属离子均有一定的吸附作用，并在20min内达到吸附平衡，pH对吸附过程影响较大，pH为5.5时Sphaerotilus natans对这4种金属离子的吸附效果最好，Sphaerotilus natans对它们的吸附选择性为Pb^2＋〉Cu^2＋〉Zn^2＋〉Cd^2＋，Pb^2＋、Cu^2＋能部分置换出已被菌体吸附的Zn^2＋、Cd^2＋。HCI和EDTA溶液可有效地将金属离子从菌体上解吸下来，解吸后的菌体可重复使用。

Biosorption of sphaerotilus natan to the heavy metal ions Pb2+ ,Cu2+ ,Zn2+ and Cd2+

The biosorption of Sphaerotilus natan to the heavy metal ions such as Pb 2+ ,Cu 2+ ,Zn 2+ and Cd 2+ was studied. The results showed that Sphaerotilus natans had a certain adsorbing effect on the heavy metal ions of copper, lead, zinc and cadmium. The process of adsorption reaches equilibrium in 20 minutes. The pH value of the solution has a great effect on the adsorption. Sphaerotilus natans showed the best adsorbing effect to the above four kinds of heavy metals ions at pH 5.5. The sequence of the adsorption selectivity of Sphaerotilus natans to the heavy metal ions was Pb 2+ >Cu 2+ > Zn 2+ >Cd 2+ . Pb 2+ and Cu 2+ can partially replace Zn 2+ and Cd 2+ adsorbed by Sphaerotilus natans. HCl and EDTA can desorb the heavy metal ions from the bacteria effectively and the bacteria can be reused.