面包酵母菌在铅铜模拟废水中的吸附动力学

来源期刊：中国有色金属学报2010年第4期

论文作者：代群威 董发勤 M. J. NOONAN 张伟

文章页码：788 - 794

关键词：环境保护；铅；铜；废水；面包酵母菌；生物吸附；动力学

Key words：environmental protection; copper; lead; waste water; Baker’s yeast; biosorption; kinetics

摘    要：探讨模拟重金属Pb²⁺-Cu²⁺混合废水中面包酵母菌的动力学吸附行为和各离子间的点位竞争吸附过程。选择面包酵母菌为吸附剂，分别对不同的Pb²⁺-Cu²⁺废水进行动力学吸附分析和二级动力学模型计算，同时，也进行SEM/EDS分析。结果表明：在最初60 min时，酵母菌对Pb²⁺-Cu²⁺废水中离子已有较好的吸附效果，在整个动力学吸附过程中，酵母菌对废水中离子的吸附关系总是存在q_t(Pb²⁺) ＞q_{t(Pb^{2+ -Cu2+})} ＞q_t(^Cu2+) 。二级动力学方程计算结果显示：在Cu²⁺竞争胁迫环境下，增大Cu²⁺的比例使酵母菌对Pb²⁺的吸附速率更快，也证明Pb²⁺在吸附点位竞争过程中的明显优势，EDS测试结果也证实这点。SEM分析发现：酵母菌吸附Cu²⁺和Pb²⁺后，菌体出现不规则变形并遭受一定的破坏，有内部物质外泄现象。酵母菌对Cu²⁺和Pb²⁺都有一个快速吸附过程，相对而言其对Pb²⁺的吸附更具优势。

Abstract: The kinetics biosorption behavior of Baker’s yeast in the simulation heavy metal waste water of Pb²⁺-Cu²⁺ was investigated. The autoclaved Baker’s yeast was chosen as a biosorbent, and then the kinetics biosorption process and second-kinetics model were analyzed, respectively. The results show that there is very good biosorption effect at first 60 min. At the same initial concentration for heavy metal ions, there are the relations:q_t(Pb²⁺) ＞q_{t(Pb^{2+ -Cu2+})} ＞q_t(^Cu2+) . The second-kinetics biosorption model’s analysis shows that the biosorption speed to Pb²⁺ becomes rapid with the initial concentration of Cu²⁺ increasing, proving that there is obvious advantage to Pb²⁺ in the biosorption sites competition process. And the analysis results of EDS approve it also. The analysis of SEM shows that the Baker’s yeast cells are broken after the biosorption of Pb²⁺ and Cu²⁺ ions. The toxicity of heavy ions to yeast cells makes the cells distort and break. The cytoplasm leaks out from the yeast cells. The biosorption of baker’s yeast to Pb²⁺ and Cu²⁺ is a rapid and preferable process, and there is a more obvious advantage for Baker’s yeast to Pb²⁺ than Cu²⁺.

基金信息：国家自然科学基金资助项目
科技部欧盟国际合作专项资助项目