Biosorption: An Eco–Friendly Technique for the  Removal of Heavy Metals

Sasmita Sabat; Kavitha; Shantha; Gopika Nair; Megha G; Niranjana C; V. Krishna

Volume : II, Issue : III, December - 2012

Biosorption: An Eco–Friendly Technique for the Removal of Heavy Metals

Sasmita Sabat, Kavitha, Shantha, Gopika Nair, Megha G, Niranjana C, V. Krishna

Abstract :

The biosorption technique can be used for the removal of pollutants from waters, those are considered as non–biodegradable. One of the most serious threats today is the heavy metal pollution that occurs in the aquatic systems. Most of the pollutants present in the waste water possess a significant threat to both environment and public health as they contain xenobiotics and heavy metals which are non–biodegradable and persistent. They possess a health hazard due to the principle of biomagnification as they seem to further accumulate in food chains. A plethora of sustainable biological materials that comprises of algae, bacteria, yeast and fungi have received enormous attention for removal of heavy metal and its recovery. Biosorption technology has advantages that are effective to treat dilute solutions of waste water harbouring heavy metals, has a low operating cost and generates minimum effluent. The dead or the living biomass may sequester the metals by the process of biosorption from water samples. The technology of biosorption employs various kinds of biomass which helps to trap heavy metals in contaminated waters. Intensive work on microbial biomass has emerged as an alternative for developing economic and ecofriendly treatment processes for waste water. The chemical processes that exist today are not economical for the treatment of large volumes of water bodies. Hence biological materials are used by virtue of their good performance, low cost and large available qualities. Here the microbial biomass used acts as an ion exchanger because of the presence of various reactive groups present on the cell surface such as carboxyl, sulphate, phosphate, sulfhydryl, and imidazole. The biosorbents is prepared by modifying the biomass with the help of various processes like granulation, pretreatment and immobilization, which results in the entrapment of heavy metals in bead like structures and by the process of desorption the beads are used to release the metal ions which can be recycled and reused for subsequent procedures. This paper summarises the great challenge for the development of the biosorption process for the metal removal by two trends using hyid technology and immobilization technology. The present review focuses on the examination of biosorbents within real and current research on biosorption and its potential application.