Bacteria-based bioremediation of uranium mining waste waters by using sol-gel ceramics

Abstract. Cells, spores and the surface layer protein (S-layer) of the Bacillus sphaericus strain JG-A12, recovered from a uranium mining waste pile, were embedded in SiO2 matrices by using sol-gel techniques. Sorption and desorption of uranium and copper by the free biocomponents and the obtained biological ceramics (biocers) were investigated. The biocer with cells possesses the highest binding capacity, followed by the S-layer biocer and the spore biocer. For renewed use of the biocers, the bound uranium and copper can be completely removed by washing with aqueous citric acid.