Adsorption of Heavy Metals from Wastewater by Starch, Cellulose, Chitin, Chitosan and Lignin Biological Macro Molecule: Review Article

Abstract

Contaminant removal from sewage is a serious difficulty on the subject of water contamination. Adsorption is a direct and efficient technique for eliminating contaminants that involves the use of solid materials known as adsorbents. Mineral, organic, or biological adsorbent materials can be utilized. At the industrial scale, activated carbon is the favored traditional material. Activated carbon is widely used to remove contaminants from wastewater streams and to absorb them from groundwater, rivers, lakes, and reservoirs, which are all sources of potable water. However, because of its expensive cost, activated carbon is not widely used. Several ways of utilizing non-conventional adsorbents have been investigated over the last three decades to generate cheaper and more effective adsorbents to remove contaminants at trace levels. This article provides an overview of liquid-solid adsorption techniques for pollution removal that use low-cost polymer adsorbents. The paper discusses the fundamentals of adsorption and provides a classification for adsorbent materials as well as numerous low-cost biological macromolecule adsorbents, includes cellulose, starch, chitin, chitosan, lignin, and their heavy metal removal capability.

Keywords

• Heavy metal ions
• Adsorption
• Biological macromolecule

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