阿维菌素发酵废菌丝体对Cu~(2+)吸附机制的研究

文章对阿维菌素发酵的废菌丝体对Cu2+进行吸附的机制进行了研究。结果表明,吸附过程可分为快速吸附和缓慢吸附至平衡两个阶段,第一阶段为被动吸附,5min接近平衡,第二阶段菌丝单位吸附量增加缓慢,反应时间相对较长。吸附过程能很好的用准二级动力学方程描述,相关系数达0.9998。采用Langmuir方程与Freudlich方程对数据拟合,Langmuir方程比Freudlich方程更好的描述对Cu2+吸附平衡行为,表现为单分子层吸附。在pH5.0下的相关系数为0.9771,得到的最大吸附量可达28.82mg/g。通过对吸附前后的红外光谱研究表明,本吸附质含有羟基(-OH)、氨基(-NH)2、酰胺基(-CONH)2、亚甲基(-CH2-)等基团。羟基、氨基、亚甲基吸收峰发生较大变化,推测其与金属离子发生了反应,酰胺基峰形变化较小,参与反应的基团较少。

Biosorption Mechanism of Copper Ion by Waste Mycelium of Avermectins

Waste mycelium of avermectins was used to remove copper ions from wastewater for the study of biosorption mechanism. Results showed that the process of biosorption can divided into two phases such as rapid sorption phase and relatively slow sorption phase. The first phase as passive sorption can approach sorption equilibrium in 5min. The sorption mass of per-material increased slowly in second phase,and time of action was relatively longer. Biosorption kinetics can be well described by second order equation,with relative coefficient of equation 0.9998. Biosorption of Cu2+ can be better described by Langmuir model than Freundlich model,implying monomolecular adsorption mechanism. The relative coefficient of the equation was 0.9771 in pH 5.0,and maximum biosorption capability was 28.82mg/g. Compared FIR scanning spectra of initial biomass with Cu2+ ion exposed cells,it can be known that the biomass contains hydroxyl group,amide group,acyl group and methylene group. It can be presumed that hydroxyl group,amido group and methylene group mostly act with metal ions,while the acyl group acts little.