A SURVEY OF MODIFIED AGRICULTURAL WASTES FOR HEAVY METAL REMOVAL FROM WASTEWATER

Heavy metal removal from wastewater is of special concern due to presence of heavy metals in environment. The discharge of various industries contains heavy metals and they affect soil fertility, water resources, aquatic organisms and ecosystem integrity. The heavy metals which mainly discharge from industries are cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), selenium (Se), vanadium (V), cobalt (Co), mercury (Hg), lead (Pb), zinc (Zn) and arsenic (As). Among various processes, adsorption process is relatively new process for removal of heavy metals from wastewater. Adsorption has certain advantages over conventional methods such as they minimize chemical and biological sludge, possess low cost, high efficiency, possibility of metal recovery and adsorbent regeneration. Thus, this review article aims to compile scattered available information on modified agricultural adsorbent for heavy metal removal.