Solidification Ability of Sr2+ by Montmorillonite-Thiobacillus Denitrificans System

Abstract

The pollution of radionuclides is extremely harmful to the human environment, and it is of great significance to study its feasible treatment methods. There are few studies on the removal of Sr2+ by the combination of microorganisms and minerals. This experiment constructed the bacteria-mineral system with the previously screened thiobacillus denitrificans and montmorillonite, and liquid ion chromatography, multifunctional X-ray diffractometer(XRD), scanning electron microscopy(SEM) and other methods were used to characterize pH and SO42- changes in the system and the removal ability and curing ability of the montmorillonite-thiobacillus denitrificans system(Mont-TD) on Sr2+ in solution. The results show that the Mont-TD system has a high removal effect on Sr2+. Adding 6 g montmorillonite and 1∶100 bacterial solution to the medium with Sr2+ concentration of 1 000 mg/L and 150 mL, after 30 d, the removal rate of Sr2+ reaches 93.2%, the solidification rate reaches 71.1%, and SrSO4 crystals are produced in the product. By constructing the Mont-TD system, the effective removal of Sr2+ in the solution is achieved, and part of it is stably solidified. Montmorillonite-thiobacillus denitrificans system can provide an idea for the treatment of strontium ion pollution in the environment.

Keywords

• montmorillonite
• thiobacillus denitrificans
• sr2+
• curing rate