The correlation between Sulfolobus metallicus attachment behaviors and surface speciation of chalcopyrite

摘要

The adsorption characteristics of thermoacidophilic archaea strain Sulfolobus metallicus DSM-6482 to chalcopyrite with different surface structures were comparatively studied in situ. The relationship between the bio-adsorption and the surface morphology and phase composition of chalcopyrite was established based on the fluorescence in situ staining microscopy (FISM), Fourier transform infrared (FT-IR) spectroscopy; sulfur K-edge X-ray absorption near edge structure (XANES) spectroscopy and scanning electron microscopy with energy dispersive spectrometry (SEM/EDS). The FISM results showed that the quantity of cell attachment on mineral surface increased with time, and the formation of biofilms was observed in 6 days. In addition, the EDS showed that adsorption quantities of cells on creviced area were much more than the cells on flat area by comparing the average content of C. As for creviced area, the content of C indicated that deficiency in S or Fe led to lower cell adsorption. For flat areas, the adsorbed carbon contents in the two chemically treated cases were much higher than the control case without treatment. This meant that the chalcopyrite surfaces treated by electrochemical corrosion could favor the bacterial adsorption and the formation of elemental sulfur (S°) detected by XANES analysis seemed to be in favor of the adsorption and growth of S. metallicus. In addition, the content of C had the positive correlation with the content of Fe/(Cu+Fe+S). It could be concluded that not only the surface microstructure but also the chemical speciation defined the cell adsorption behavior.