An Overview of Removal of Heavy Metal Ions From Toxic Aqueous Solution Using Pani-Based Adsorbents

In the present time, water pollution has become a quibbling issue in the current environmental engineering and protection senario. The most important aspect of nanocomposite is to develop economic and bio-friendly route for the synthesis of nanosamples. Various methods such as ion exchange, reverse osmosis, filtration, adsorption, etc. for removing the metal ions from toxic water were studied. Among these methods, adsorption technique is widely used due to low cost. Basically, over the last years, conducting polymer based nanocomposites showed their application in different heavy metal ions especially Hg (II), Cd(II), Cr(VI), Pb(II), As(V), etc. Among the various conducting polymers, PANI plays the most important role in extracting the necessary heavy metal ions. The current review mainly focuses on the synthesis, adsorption and mechanism of different PANI-based adsorbents like PANI/iron oxide, PANI/ZNO, PANI/GO, and PANI/CHITOSAN, etc., which extract the heavy metal ions.