Studies on potential applications of biomass for the separation of heavy metals from water and wastewater

Abstract

Heavy metal pollution has become a more serious environmental problem in the last several decades as a result of its toxicity and insusceptibility to the environment. This paper attempts to present a brief summary of the role of biomass in heavy metal removal from aqueous solutions. Undoubtedly, the biosorption process is a potential technique for heavy metal decontamination. The current spectrum of effective adsorbents includes agricultural waste material, various algae, bacteria, fungi and other biomass. This paper also discusses the equilibria and kinetic aspects of biosorption. It was apparent from a literature survey that the Langmuir and Freundlich isotherms are by far the most widely used models for the biosorption equilibria representation, while pseudo-first and second order kinetic models have gained popularity among kinetic studies for their simplicity. Additional features on biosorption experiments utilizing a fixed bed column are also highlighted, as they offer useful information for biosorption process design. © 2008 Elsevier B.V. All rights reserved.