酵母菌对不同液相体系中锌离子的吸附行为

Biosoroption behavior of yeast to zinc ions in different liquid systems

主要对面包酵母菌在Zn2+和Zn2+-Pb2+两种离子体系中Zn2+的吸附行为进行了探讨。选择灭活面包酵母菌为吸附剂,对pH、菌体加入量等吸附影响因素进行了探讨并进行了吸附动力学过程和等温吸附效果的研究。结果表明,不同离子体系中相同初始浓度情况下,动力学研究显示实验所用面包酵母菌对溶液中Zn2+而言是一种快速高效的生物吸附剂,且在整个吸附过程中存在:qt(Pb2+)>qt(Zn2+-Pb2+)>qt(Zn2+)。实验条件下,以单离子体系中的Zn2+、Pb2+和双离子体系中的总离子为研究对象时,都能很好符合Langmuir等温吸附模型,计算获得面包酵母菌对不同离子体系的最大吸附量大小顺序为:qmax(Zn2+-Pb2+)>qmax(Zn2+)>qmax(Pb2+);然而通过对动力学吸附过程、实际平衡吸附量qeqex、吸附能力参数KL和EDS测试结果的综合分析,认为面包酵母菌对各体系中离子的吸附能力大小顺序为:Pb2(单+)>(Zn2+-Pb2+)>Zn(2单+)。同时认为Pb2+的存在对面包酵母菌吸附Zn2+的行为过程具有强烈抑制作用。

This paper is mainly to study the biosorption behavior of baker＇s yeast on zinc ion in two kinds of liquid systems of Zn^2＋ and Zn^2＋-Pb^2＋.Autoclaved baker＇s yeast was chosen as biosorbent,and then the effect of pH,biomass dosage,the kinetics process and isotherm effect were studied in different systems.At the same heavy metal ions initial concentration,the kincetics showed that baker＇s yeast is fast and effective biosorbent to Zn^2＋,and there is always the relation： qt（Pb^2＋）〉qt（Zn^2＋-Pb^2＋）〉qt（Zn^2＋）.The isotherm biosorption of baker＇s yeast to Zn^2＋,Pb^2＋ in the single system and the total ions in the double system were all according with Langmuir model,qmax（Zn^2＋-Pb^2＋）〉qmax（Zn^2＋） 〉 qmax（Pb^2＋）.However,the synthesis analysis to kinetics process,equilibrium sorption quantity（qeqex）,sorption capacity parameter（KL） and EDS results showed that the sorption capacity of baker＇s yeast had the relations： Pb2＋（single）〉（Zn^2＋-Pb^2＋）〉 Zn^2＋（single）.The concomitance of Pb^2＋ had obvious restrain effect to the biosorption behavior of baker＇s yeast to Zn^2＋.