黑根霉菌自由细胞和固定化细胞对重金属铅的生物吸附

Study on Biosorption of Lead on Rhizopus Stolonifer Free Cells and Immobilized Cells

通过分组实验,分别研究了黑根霉菌自由细胞和固定到聚氨酯泡沫立方体上的细胞对pb^(2+)的生物吸附,以确定固定化对pb^(2+)吸附的影响。自由细胞需要30min达到吸附平衡,而固定化细胞因为聚氨酯泡沫的作用需要120min。pH值对Pb^(2+)的吸附效果具有很大的影响,吸附的最佳pH值为5.0。同时把在不同pb^(2+)浓度下的吸附平衡数据用Langmuir吸附模式线性拟合,得出自由细胞和固定化细胞的最大吸附量分别为166.7mg/g和400mg/g。最后通过对五种化学药剂解吸效果的研究,得出0.1mol/L的HNO_3对吸附到固定化黑根霉菌上的pb^(2+)解吸效果不错,解吸率达到99.2%。

The biosorption of Pb^(2+) on Rhizopus stolonifer free cells and cells immobilized in 15 millimeter cubic polyurethane foam in batch experiments have been studied respectively in this paper to determine the effect of immobilization on Pb_(2+)accumulation. When free cells were used, the sorption equilibrium was reached in 30 minutes, but with immobilized cells it took 120 minutes as a consequence of the effect of polyurethane foams, pH value was found critical for Pb^(2+) accumulation, the optimum being 5.0. At the same time adsorption equilibrium data in different Pb^(2+) concentrations have been linerized by Langmuir adsorption model, the maximum uptake capacities for free cells and immobilized cells being 166.7 mg/g and 400 mg/g respectively. In the end desorption of Pb_(2+) adsorbed by Rhizopus stolonife immobilized cells by 0.1 mol/L HNO_3 was efficient by studying the desorption effects of five chemical substances, desorpton rate being 99.2 percent.