Immobilization of Acidithiobacillus ferrooxidans on sulfonated microporous poly(styrene–divinylbenzene) copolymer with granulated activated carbon and its use in bio-oxidation of ferrous iron

Abstract

The immobilization efficiencies of Acidithiobacillus ferrooxidans cells on different immobilization matrices were investigated for biooxidation of ferrous iron (Fe2+) to ferric iron (Fe3+). Six different matrices were used such as the polyurethane foam (PUF), granular activated carbon (GAC), raw poly(styrene–divinylbenzene) copolymer (rawSDVB), raw poly(styrene–divinylbenzene) copolymer with granular activated carbon (rawSDVB-GAC), sulfonated poly(styrene–divinylbenzene) copolymer (sulfSDVB) and sulfonated poly(styrene–divinylbenzene) copolymer with granular activated carbon (sulfSDVB-GAC). The sulfSDVB-GAC polymer showed the best performance for Fe2+ biooxidation. It was used at packed-bed bioreactor and the kinetic parameters were obtained. The highest Fe2+ biooxidation rate (R) was found to be 4.02g/Lh at the true dilution rate (Dt) of 2.47 1/h and hydraulic retention time (τ) of 0.4h. The sulfSDVB-GAC polymer was used for the first time as immobilization material for A. ferrooxidans for Fe2+ biooxidation.