黑曲霉（Aspergillus niger）对Pb2+的吸附特性研究

以黑曲霉菌丝体作为吸附剂,通过静态吸附实验研究了各种因素对其吸附去除废水中Pb2+的影响。结果表明：当Pb2+初始浓度为50 mg/L,吸附剂用量为1．0 g/L,吸附时间为45 min,pH为5．0时,吸附效果最佳。此时吸附量为44．1 mg/g,去除率为90．86%。使用准二阶动力学方程可较好的拟合黑曲霉对Pb2+的吸附,表明该吸附过程以化学吸附为主。等温吸附过程可用Freundlich方程描述,说明该吸附为多分子层吸附。傅立叶红外光谱分析表明,黑曲霉吸附剂表面的酯羰基(-COO-)、羧基(-COOH )和羟基(-OH )在吸附Pb2+的过程中发挥主要作用。

Study on Sorption of Pb2+by Aspergillus niger

Using Aspergillus niger as a biosorbent, static adsorption experiments were conducted to study the characteristics of the biosorbent to adsorb Pb2+ from aqueous solutions. Results showed that the optimal initial concentration of Pb2+, biomass dosage, sorption time and pH value were found to be 50 mg/L, 1. 0g/L, 120 min, 5. 0, respectively. Under these optimal condi-tions, the sorption amounts and removal efficiency of Pb2+ could reach 44. 1mg/g and 90. 86%, respectively. The biosorption of Pb2+ by Aspergillus niger fit well with pseudo-second-order Lagergren model, indicating that the adsorption process is domina-ted by chemical. and Freundlich isotherm model can well describe this process . FTIR data indicated that the functional group of-NH2 , -COOH and -OH played a principal role in the sorption.