Activated sludge as biosorbent of heavy metals

摘要

Attempts were made to recover cadmium, copper, nickel, lead and zinc in aqueous solution by three different types of biomasses: Activated sludge (A.S.), brewer's yeast and barley's root. The former one was the most effective to uptake metal ions. pH solution was found to be critical to metal ions uptake, the optimum pH range was 4-5. Effect of biomass loading was also investigated, the optimum biomass concentration was 1 g L~(-1). Temperature (20-60 deg C) had no effect on the level of accumulation of all metal ions tested. Adsorption behaviour of the five metals fitted Langmuir isotherm more than Freundlich model.