Ahmad Ashfaq
Abstract
Heavy metal containing wastewaters cause detrimental effects on all forms of life upon direct discharge to the environment. There has been steady progress in studying the biosorption of heavy metals, resulting in the identification of various types of sludges that show very promising uptake of metallic ions. The equilibrium uptake of various metal ions with industrial sludge under different conditions such as solution pH, contact time, biosorbent loading and temperature are considered by several researchers. Distinctive sorption equilibria and kinetic models are of extensive use in explaining the biosorption of heavy metals, denoting the need to highlight and summarize their essential issues. This paper reviewes the studies in the field of biosorption using sludge as an effective biosorbent.