Recent advances in polyaniline-based nanocomposites as potential adsorbents for trace metal ions

Abstract Nowadays, with a rapid extension of urbanizations and industrializations, a huge amount of metal discharge directly entered into the water bodies and contaminated the aquatic environment that has become a serious worldwide environmental problem. Considerable efforts are already in motion to address this issue in terms of developing more efficient and high-quality techniques to remove these toxic metal ions from water bodies to save the human beings from its adverse effects on their health. Among all the reported methods available, there have been growing interests in the adsorption and ion exchange that are capable of removing of toxic metal ions even in low concentration from the contaminated water. Various materials have been reported for the removal of metal ions from wastewaters such as biomasses, fly ash, silica gel and alumina, resins, rice husk ash, and activated carbon, but polyaniline nanocomposites have emerged as one of the most attractive conducting polymers due to high stability, easy methods of synthesis, feasibility of electric conductivity, and finally the low cost of the aniline monomer. The present chapter deals with the recent advances in the synthesis and characterization of polyaniline-based nanocomposites used as adsorbents and ion-exchange materials. In spite the removal and recovery of heavy metal ions from wastewaters, these nanocomposite ion-exchange materials can also be effectively utilized in other fields (e.g., photochemical degradation of organic pollutants, antimicrobial agents, and nanoconducting material). In the future, polyaniline-based nanocomposites are expected to open new approaches for demonstrating their outstanding applications in diverse fields.