Cr(Ⅵ)吸附菌的分离及其对Cr(Ⅵ)吸附的研究  

Cr(Ⅵ)Absorption Bacteria:Screening and Cr(Ⅵ)Adsorption

作　　者：张勇 龚小宝[2] 孙飞 

机构地区：[1]中铁建工集团北京安装工程有限公司,江苏苏州215163 [2]华东交通大学土木建筑学院,江苏南昌330013 [3]山东龙信达咨询监理有限公司,山东济南250006

出　　处：《环境科学与技术》2011年第7期105-109,共5页Environmental Science & Technology

摘　　要：从某受铬污染的土壤中分离出一株铬吸附菌,经初步分离鉴定为芽孢杆菌。利用微生物培养基对其进行扩大培养,然后制备生物吸附剂,研究了吸附剂对C(rⅥ)的吸附行为及pH、C(rⅥ)初始浓度、温度和共存离子对吸附的影响。结果表明,吸附剂对C(rⅥ)有较好的吸附效果,最佳吸附条件为pH=9.0,初始浓度为40 mg/L,最佳温度为35℃,共存离子Zn2+降低了C(rⅥ)的吸附量,Cu2+增加了吸附量。用Langmuir、Freundlich及Dubinin-Raduskevich吸附等温模型对吸附过程进行拟合发现:Langmuir模型可以很好地反映芽孢杆菌对C(rⅥ)的吸附特性,在308 K时最大吸附量为126.57 mg/g;通过扫描电镜看出,菌体表面结构由疏松变紧密,较好反映了菌体表面结构的变化。研究表明,芽孢杆菌对C(rⅥ)有很好的吸附效果,为C(rⅥ)的去除提供了新的途径。A chromium absorption strain of bacteria was isolated and screened from Cr-contaminated soil and was identified as Bacillus sp.in a lab-scaled experiment,involving culture of the microbiological media and preparation of the bio-sorbent. Adsorption behavior of the bio-sorbent and the influence of pH,temperature and the co-existed ions and initial C（rⅥ） concentration of the wastewater sample on the adsorption were studied,which resulted in the optimal Cr（Ⅵ）adsorption condition.Adsorption capacity of the bio-sorbent reached 126.57 mg/g at Langmuir,Freundlich and Dubinin-Radushkevick isotherms were applied to fitting adsorption equilibrium data,thus it was found that Langmuir isotherm adsorption model was the best reflecting the adsorption characteristics.SEM used in the study presented the images of the change of the bacteria cells surface before and after the adsorption process.

关 键 词：芽孢杆菌 分离 吸附 Cr(Ⅵ) 

分 类 号：X703[环境科学与工程—环境工程]