纤维微菌C6对水中Cr(Ⅵ)去除条件优化及机理研究

The conditions optimization for removing Cr (Ⅵ) from water by Cellulosimicrobium sp. strain C6 and study on its removal mechanism

摘要:

为解决水体中重金属Cr(Ⅵ)污染问题，从成都市某皮革厂附近受重金属污染的土壤中筛选得到一株对Cr(Ⅵ)有较高抗性和去除率的菌株，鉴定后将其命名为纤维微菌C6(Cellulosimicrobium sp.).利用单因素实验对影响纤维微菌C6去除Cr(Ⅵ)的四个因素：pH，温度，接触时间，初始Cr(Ⅵ)浓度进行了探究.在单因素实验的基础上，通过四因素三水平BoxBehnken响应面法优化纤维微菌C6对Cr(Ⅵ)的去除条件，结果显示，当pH为7.85，温度为34.07 ℃，接触时间为2.88 d，初始Cr(Ⅵ)浓度为40.08 mg/L时，纤维微菌C6对Cr(Ⅵ)的最大去除效率可以达到95.75%，扫描电镜显示，未处理的纤维微菌C6菌体表面清晰光滑且分散，Cr(Ⅵ)处理过的菌体表面不规则，有颗粒状沉淀.红外光谱分析证明了菌体表面的官能团可能与吸附Cr(Ⅵ)有关.研究表明，纤维微菌C6菌体对Cr(Ⅵ)具有良好的去除效果，可用于处理含Cr(Ⅵ)废水.

Abstract:

In order to solve the problem of heavy metal Cr (Ⅵ) pollution in water, a strain with high resistance and removal rate to Cr (Ⅵ) was screened from the soil contaminated by heavy metals near a leather factory in Chengdu. After identification, it was named Cellulosimicrobium sp. strain C6 (Cellulosimicrobium sp). Based on singlefactor experiments, four factors (pH, temperature, contact time and initial Cr (Ⅵ ) concentration) affecting the removal of Cr (Ⅵ) were optimized by BoxBehnken response surface method. The results showed that when the pH was 7.85, the temperature was 34.07 ℃, the contact time was 2.88 days, and the initial Cr (Ⅵ) concentration was 40.08 mg/L, the maximum removal efficiency of Cellulosimicrobium sp. strain C6 on Cr (Ⅵ) can reach 95.75%. Scanning electron microscope results showed that the surface of the untreated Cellulosimicrobium sp. strain C6 was clear, smooth and dispersed. The surface of Cr (Ⅵ) treated strain was irregular with granular precipitation. Fourier transform infrared spectroscopy analysis showed that the functional groups on the surface of Cellulosimicrobium sp. strain C6 might be related to the adsorption of Cr (Ⅵ). Cellulosimicrobium sp. strain C6 can be used to treat Cr (Ⅵ)containing wastewater .