戊二醛交联酵母菌对Zn2+，Cd2+和Hg2+的吸附行为

用戊二醛作为交联剂,采用简单的方法制备机械强度高的交联酵母菌.考察菌体吸附Cd2 的影响因素,包括交联剂的用量,pH,金属离子初始质量浓度,吸附时间等,研究菌体对不同质量浓度的Zn2 ,Cd2 和Hg2 的吸附率.结果表明,戊二醛的最佳用量(体积分数)为1.0%,菌体对金属离子的吸附平衡时间为30 min,吸附过程符合准二级动力学方程.吸附为Langmuir单分子层吸附,相对于未交联菌,交联酵母菌对Cd2 的吸附容量提高2倍;pH实验表明,交联酵母菌对金属离子的吸附受酸度影响小.用于冶金厂废水的处理结果显示,0.050 0 g的交联酵母菌,对5.3 mg/L的Cd2 污水的去除率为80.6%,用0.1 mol/L的EDTA再生该吸附剂,Cd2 的解析率达92.1%.

Adsorption Behaviour of Baker's Yeast Cross-linking with Glutaraldehyde for Zn2+,Cd2+ and Hg2+

Cross-linked yeast with higher mechanical strength was prepared using glutaraldehyde, and factors impacting adsorption of cross-linked yeast on Cd²⁺ were investigated, including glutaraldehyde dosage, pH, initial concentration of metal and adsorption time.Additionally, removal rates of different concentrations of Zn²⁺, Cd²⁺ and Hg²⁺ by cross-linked yeast were studied.Theresults showed that the adsorption process of cross-linked yeast for metals reached equilibrium at 30 min when the glutaraldehyde dosage was 1.0 %, and the adsorption process fitted the pseudo second-order kinetics.The adsorption for Cd²⁺ fitted the Langmuir monolayer model.Compared with the non-cross-linked yeast, the adsorption capacity of the cross-linked yeast increased twofold.The adsorption was slightly affected by pH.Cross-linked yeast was used to treat metallurgical wastewater, and the results showed that the removal rate for Cd2+ from 5.3 mg/L wastewater was 80.6% when 0.050 0 g cross-linked yeast was used; when the cross-linked yeast was regenerated by 0.1 mol/L EDTA, desorption rate of Cd²⁺ reached 92.1%.