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

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 .