沼泽红假单胞菌对Zn^2＋的吸附性能研究

采用沼泽红假单胞菌为生物吸附剂,研究了锌离子初始浓度、pH值、吸附剂用量、菌龄、吸附时间等因素对沼泽红假单胞菌生物吸附模拟废水中锌的影响,探讨了吸附动力学特征。结果表明,沼泽红假单胞菌在Zn2＋初始质量浓度为200 mg/L、吸附剂用量0.5 g/L、菌龄32 h、pH=7、吸附时间80 min的条件下,对Zn2＋的吸附量为88.23 mg/g;其吸附行为可以用Langmuir和Freundlich吸附等温方程描述,但更符合Freundlich吸附等温方程。对Zn2＋的吸附过程符合二级动力学特征。

Study of the adsoprtion properties of zinc ions in the aqueous solutions by rhodopseudomonas palustris

This paper concerned about a renovated method of rhodopseudomonas palustris cells as a biologic adsorbent used in an absorption test of Zn2+ in aqueous solution simulated wastewater.For the research purpose,we have done a series of experiments to determine and define the influencing factors on the biosorption process,such as the initial concentration of Zn2+,pH value,the biomass concentration,the bacteria culturing time and the adsorbing time to Zn2+ along with our definition of their dynamic feature.The results showed that the maximum adsoption capacity for Zn2+ of R.palustris was 88.23 mg/g dry biomass under the following optimal conditions: Zn2+ concentration 200 mg/L,the bacteria cultured 32 h later with the biomass of 0.5 g/L,as well as the pH=7,absorption time 80 mins.Its adsorption behavior could be described by either the Langmuir adsorption isotherm equation or the Freundlich isotherm adsorption equation,the latter equation being the better.In addition,the adsorption of Zn2+ fit a pseudo-second order kinetics equation.