Microbial biomass represents a potentially cost-effective sorbent for water treatment applications. High sorption capacities for both cations and anions are demonstrated here for viable and autoclaved cell suspensions of the Gram-negative bacterium Shewanella putrefaciens. FTIR absorption spectra and pHdependent zeta-potentials are similar for the viable and killed bacterial cells. Potentiometric titrations, however, reveal a two to three times higher OH- buffering capacity for the living cells. The Cu2+ sorption capacity of the viable cells is also about twice that of the autoclaved cells. Sorption of fluoride and phosphate is not pH-dependent, although an initial addition of acid or base was needed to activate the anion binding sites. Uptake of fluoride is comparable for viable and killed cells.
- Shewanella putrefciens