Studies on mechanisms of silver biosorption by Aeromonas SH10
气单胞菌SH10吸附银离子机制的研究

The study on mechanisms of metal biosorption is helpful to improve the biosorption ability of organism. Mechanisms of silver biosorption by Aeromonas SH10 were discussed from several aspects such as electrostatic adsorption, ion exchange, complexation and deposition. Results showed that silver biosorption by SH10 didn't mainly depend on ion exchange duo to only slight increase of the contents of Na~ , K~ , Mg~ 2 in solution after biosorption, while electrostatic adsorption was found to be responsible for biosorption. Adsorptive capacity of silver ion decreased distinctly after functional groups such as carboxyl, amino and lipid groups on SH10 cell wall were chemically modified, respectively. Combined with FTIR spectra, amino groups were confirmed to be the main active groups that could combine with silver ion. SEM illustrated precipitation could take place on the cell wall of SH10.