(1. 西南科技大学 固体废物处理与资源化教育部重点实验室，绵阳 621010；
2. 西南科技大学 环境与资源学院，绵阳 621010；
3. 林肯大学 农业与生命科学系，新西兰 基督城8006)
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 ＞ ＞ 。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。
关键字: 环境保护；铅；铜；废水；面包酵母菌；生物吸附；动力学
（1. Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education,
Southwest University of Science and Technology, Mianyang 621010, China;
2. School of Environment and Resource, Southwest University of Science and Technology, Mianyang 621010, China;
3. Agriculture and Life Science Division, Lincoln University, Christchurch 8006, New Zealand）
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: ＞ ＞ . 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+.
Key words: environmental protection; copper; lead; waste water; Baker’s yeast; biosorption; kinetics
