An increase in industrial, agricultural practices and several anthropogenic activities adds a significant amount of heavy metals in soil and water. Presence of these metals beyond the threshold limit is toxic for the flora and fauna of the surroundings. So, there is a need for removing the harmful heavy metals from the environment. Conventional methods such as precipitation, evaporation, electroplating, ion exchange, membrane processes, etc. have been ineffective because of technical and economic issues. Biosorption is a potential bioremediation technique that can be used for the removal of pollutants from aqueous medium and soil by the help of biosorbents (algae, fungi, bacteria, plants etc.). For increasing the biosorption capacity of biosorbents, they can be modified physically, chemically and genetically. Various factors affect the biosorption activity such as initial pH, temperature, bacterial activities and kinetics. This study describes the bacterial adsorbents, their modification and mechanism for removal of copper. A brief description of Langmuir and Freundlich isotherm modelling is provided in this paper.
Keywords: Bioremediation, biosorption, biosorbent, bacteria, heavy metals, copper.
The intensive development of industry, agricultural practices and modern technologies are leading to the release of significant amount of contaminants to the environment (Ayres, 1992). Metals are inorganic form of contaminants whose extensive use has caused significant environmental pollution that mainly affects soil, watercourses, atmosphere and living systems (Kasassi et al., 2008). Mercury, lead, cadmium and chromium (VI) are considered as toxic metals; whereas, copper, nickel, cobalt and zinc are not as toxic, but their e...
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