固定化啤酒酵母对锶离子的吸附

Biosorption of Sr^(2+) by immobilized Saccharomyces cerevisiae

用2%海藻酸钠(SA),4%氯化钙(CaCl2)包埋法制备了固定啤酒废酵母。考察了菌体含量对固定化菌体强度的影响,研究了pH值、温度、Sr2+初始浓度、吸附时间等外界因素对固定化啤酒酵母吸附溶液中Sr2+的影响。结果表明:菌体含量为10%时,制备的固定化菌体具有较好的机械强度。固定化啤酒废酵母对Sr2+最佳吸附条件为:pH=4.5,温度30℃,Sr2+起始浓度50 mg/L,吸附时间4 h。Sr2+浓度在10～150 mg/L范围内,固定化啤酒废酵母对Sr2+的吸附符合Langmuir模型和Freundlich模型,但符合Freundlich模型的程度更优。

Saccharomyces cerevisiae was entrapped in a mixture of 2% SA,and 4% CaCl2.The mechanical strength of SA-CaCl2 immobilized beads,and the effects of adsorption treatment conditions,such as pH,temperature,Sr2＋ initial concentration and reaction time,on the adsorptive capacity were investigated.The results show that the mechanical strength of immobilized Saccharomyces cerevisiae is higher at 10% Saccharomyces cerevisiae,the optimal adsorption condition for immobilized Saccharomyces cerevisiae is as follows：pH 4.5,temperature 30 ℃,Sr2＋ initial concentration 50 mg/L,adsorption time 4 h.The sorption process of Sr2＋ is in accordance with both Langmuir and Freundlich isotherm when the concentration of Sr2＋ is 10-150 mg/L,but complies with Freundlich model better.