Biosorption of Heavy Metals by Bacteria Isolated from Activated Sludge
- 402 Downloads
Twelve aerobic bacteria from activated sludge were isolated and identified. These included both Gram-positive (e.g., Bacillus) and Gram-negative (e.g., Pseudomonas) bacteria. The biosorption capacity of these strains for three different heavy metals (copper, nickel, and lead) was determined at pH 5.0 and initial metal concentration of 100 mg/L. Among these 12 isolates, Pseudomonas pseudoalcaligenes was selected for further investigation owing to its high metal biosorption capacity. The lead and copper biosorption of this strain followed the Langmuir isotherm model quite well with maximum biosorption capacity (q max) reaching 271.7 mg of Pb2+/g of dry cell and 46.8 mg of Cu2+/g of dry cell at pH 5.0. Study of the effect of pH on lead and copper removal indicated that the metal biosorption increased with increasing pH from 2.0 to 7.0. A mutual inhibitory effect was observed in the lead-copper system because the presence of either ion affected the sorption capacity of the other. Unequal inhibitions were observed in all the nickel binary systems. The increasing order of affinity of the three metals toward P. pseudoalcaligenes was Ni < Cu < Pb. The metal biosorptive potential of these isolates, especially P. pseudoalcaligenes, may have possible applications in the removal and recovery of metals from industrial effluents.
Index EntriesActivated sludge biosorption copper adsorption lead removal bioremediation
Unable to display preview. Download preview PDF.
- 1.Kasan, H. C. and Baecker, A. A. W. (1989), Water Sci. Technol. 21, 297–303.Google Scholar
- 3.Leung, W. C., Wong, M. F., Chua, H., Lo, W., Yu, P. H. F., and Leung, C. K. (2000), Water Sci. Technol. 41(12), 233–240.Google Scholar
- 10.Atkinson, B. W., Bux, F., and Kasan, H. C. (1996), Water Sci. Technol 43(9), 9–15.Google Scholar
- 11.Goddard, P. A. and Bull, A. T. (1989), Appl. Microbiol. Biotechnol 31(3), 308–313.Google Scholar
- 13.Pumpel, T., Pernfuss, B., Pigher, B., Diels, L., and Schinner, F. (1995), J. 2nd. Microbiol. 14(3–4), 213–217.Google Scholar
- 14.Thompson, J. B. and Beveridge, T. J. (1993), in Particulate Matter and Aquatic Contaminants, Rao, S. S., ed., Lewis Publishers, Chelsea, MI, pp. 65–104.Google Scholar
- 16.Norberg, A. B. and Enfors, S. O. (1982), Appl. Environ. Microbiol. 44, 1231–1237.Google Scholar
- 19.Ting, Y. P., Lawson, F., and Prince, I. G., (1990), Aust.J. Biotechnol. 4, 197–200.Google Scholar
- 20.Wong, P. K., Lam K. C., and So, C. M., (1993), Appl. Microbiol Biotechnol. 39, 127–131.Google Scholar