固定化啤酒废酵母对Pb^(2+)的吸附

Biosorption of Pb^(2+) by Immobilized Discarded Brewers Yeast

用2%海藻酸钠与1%明胶混合为包埋剂固定啤酒酵母废菌体,研究固定化啤酒废酵母对Pb2+的吸附行为。利用原子吸收光谱法测定Pb2+含量。结果表明,固定化啤酒废酵母吸附Pb2+受吸附时间、吸附温度、溶液pH值、酵母添加量和Pb2+起始浓度等因素影响。实验确定了固定化啤酒废酵母对Pb2+的最佳吸附条件。即:pH为3.0～5.0,Pb2+浓度为100mg.L-1,酵母添加量1.2g.L-1,吸附温度25℃,吸附时间120min。在一定的浓度范围内啤酒废酵母对Pb2+的吸附符合Langmuir吸附模型和Freundlich吸附模型,但符合Freundlich吸附模型的程度更优。

Discarded brewers yeast was entrapped in a mixture of 2% alginate sodium and 1% gelatin.The biosorption of lead ion by immobilized yeast was studied.The content of Pb2+ was determined by atomic absorption spectrometry(AAS)analysis.It is shown that sorption time,temperature,pH,yeast recruitment,and Pb2+ initial concentration influence the biosorption of Pb2+.The optimal sorption conditions for immobilized yeast are that pH is 3.0~5.0,Pb2+ concentration is 100 mg/L,yeast recruitment is 1.2 g/L,sorption temperature is 25 ℃,and sorption time is 120 min.The sorption process of lead in determinated concentration is in accordance with both Langmuir and Freundlich isotherm,but better complys with Freundlich model.