Role of Adsorbents in Treatment of Pollutants from Aqueous Medium

This paper will provide an outline of the dissolved pollutants and their removal techniques from water and wastewater. Dissolved impurities are omnipresent in all kinds of water like ground water, surface water and other industrial sewage. Many methods are available for the treatment of dissolved pollutants. Rather than the conventional methods such as membrane technology, coagulation- flocculation method, electro dialysis, and ion exchange method for removing dissolved impurities from a different kind of water, the applicability of the adsorption technique is a simple, economical and the most potential one. Adsorbents may be conventional and non-conventional. Activated carbon and silica gel are included in conventional materials. Activated carbon is preferred material for removing pharmaceutical waste, heavy metals, and dyes from an aqueous medium. They can remove larger and smaller particles from water and wastewater due to their porosity. Among non-conventional methods, clay minerals and zeolites are used in both natural and modified forms as potential adsorbents. Bio-sorbents like industrial waste, agro waste, and chitosan have unique properties to be used as adsorbents to remove dissolved impurities from an aqueous medium. It also outlines mechanism of adsorption and complex relation between adsorbents and adsorbates. Considering the applicability of different adsorbents discussed here for the removal of heavy metals, pharmaceutical waste, dyes, and organic waste, it is expected that this technique can be helpful in further treatment in variety of water and wastewater.