Synthesis and characterization of polyaniline/chitin (squid pens) for the removal of chromium (vi) from aqueous solution

Abstract

The rapid growth of the industrial sector has contributed to the increasing amount of heavy metal waste in environmental water bodies. It has become a critical situation in many developing countries. Among the heavy metals, chromium (Cr) (VI) has been studied extensively due to its toxic nature in aqueous solution. Recently, bio-conducting polymers have been reported to be successful in removing heavy metals from aqueous solutions. In this study, chitin was extracted from squid pens and integrated with polyaniline (PANI) via a chemical oxidative method. The integration of chitin with PANI was confirmed by Fourier Transform Infrared (FTIR) spectroscopy, which indicated that the essential peaks of both chitin and PANI were present in the PANI/chitin composites. The removal of Cr (VI) was evaluated by Atomic Absorption Spectroscopy (AAS). Several removal optimizations were made by evaluating the effects of pH, contact time, and mass of adsorbent. The results revealed that PANI/chitin removed the highest percentage of Cr (VI) at pH 3, with 12 minutes of contact time and 20 mg of the adsorbent in a solution with an initial concentration of 10 ppm Cr (VI) at 298.15 K.