Synthesis and Characterization of Nanocomposite Ion Exchanger for the Removal of Heavy Metals

Among the conducting polymers, polyaniline (PANI) and polypyrrole (PPy) are the most popular. According to the Web of Science, more than 10,000 papers appeared in the past 30 years on various aspects of chemistry, physics, and engineering of PANI. This is due to the cheapness and easy availability of raw materials, ease of synthesis, good environmental stability, high electrical conductivity and simple doping/dedoping chemistry. The polymer–metalnano composites are promising candidates based on the fact that the small sized particles enhance the properties while the polymer matrix offers flexible functionalities to control host-guest interaction to ensure the growth and distribution of metal nanoparticles. Organic-inorganic hybrid materials prepared by sol-gel approach have attracted a great deal of attention in material science. Organic polymeric part of the composite provides mechanical and chemical stability whereas the inorganic part supports the ion-exchange behavior and thermal stability. Such modified composite materials can be applied as electrochemically switchable ion exchanger [1,2] for water treatment, especially water softening. The synthesis of hybrid ion exchangers with controlled functionality and hydrophobicity could open new avenues for organ metallic chemistry, catalysis, organic host-guest chemistry, analytical chemistry [3-5], hydrometallurgy, antibiotic purification, separation of radioactive isotopes and large scale application in water treatment and pollution control [6,7]. Thus, organic-inorganic hybrid materials are expected to provide many possibilities as new composite materials. Accordingly, the hybrid can be used to modify organic polymer materials or to modify inorganic glassy materials. In addition to these characteristics, the hybrid materials can be considered as new composite materials that exhibit very different properties from their original components, that is, organic polymer and inorganic materials especially in the case of molecular level hybrids. Thus, the synthesis of polymeric/inorganic composites has received a great deal of attention because it provided new materials with special mechanical, chemical, electrochemical, and optical as well as magnetic properties [8-11].A few such excellent ion exchange materials have been developed and are successfully being used in chromatographic techniques [12-14]. An inorganic ion exchanger based on organic polymeric matrix is an interesting material, as it possesses the mechanical stability due to the presence of organic species and the basic characteristics of an inorganic ion exchanger regarding its selectivity for some particular metal ions [15-17]. It was therefore considered to synthesize such hybrid ion exchangers with a good ion exchange capacity, high stability, reproducibility, and selectivity for heavy metal ions, indicating that they are useful in environmental applications. Synthetic ion exchangers based on tetravalent metals have been the objects of considerable study in recent years because of their selectivity and intercalation properties. Zirconium based ion exchangers have received attention because of their excellent ionexchange behavior and some important chemical applications in the field of ion exchange, ion-exchange membrane, and solid state electrochemistry [18]. Goward et al. [19] have reported that polyaniline Zr(IV)tungsten phosphate nano composite ion exchanger was used for the selective separation of La3+ and the literature reveals that several three-component ion exchangers, that is, zirconium (IV)iodooxalate, zirconium(IV)phosphosilicate, zirconium (IV)phosphoborate, and zirconium (IV) tungsten phosphate [20], behavior studied for their synthesis, ion-exchange behavior, and analytical applications. This work deals with the synthesis, characterization, and the study of ion-exchange properties of polyaniline Zr(IV)iodate as a new ion exchanger. Volume 3 Issue 2 2018