A Study on Sustainable Adsorbents for Heavy Metals Removal

. Adsorption techniques are widely used in the treatment of wastewater for the removal of heavy metals. These days the extensively used adsorbent is activated carbon, which can be extracted from various agricultural by-products such as walnut shells, groundnut shells, coconut shells, which gives best results in treating heavy metals. But the process of obtaining activated carbon into its finite form and regeneration requires high cost. In the era of advanced development, the world at present faces the scarcity of freshwater resources; it is essential to examine other possibilities that decrease the burden on existing resources. Furthermore, because heavy metals are hazardous even at trace levels, an environmentally safe removal technique required the use of inexpensive adsorbents. Adsorption has acquired popularity as a low-cost waste disposal method. The adsorption process and the many adsorbent kinds that are now on the market are the main topics of this chapter. It also includes low-cost adsorbents that explain the adsorption reaction situation, such as industrial and agricultural waste. When choosing adsorbents, the following factors are important: cost-effectiveness, technological application, and ease of access to raw materials with minimal adverse effects on the system. The chapter is interested in that it discusses a variety of adsorbents and how well they remove heavy metals from wastewater.