Chemical and radiation grafted chitosan for the mitigation of arsenic from contaminated water

Abstract

The removal of As (V) from aqueous solution was investigated with the grafted polymeric adsorbent (chitosan-g-HEMA) synthesized by using high energy ⁶⁰Co gamma radiation as well as by conventional chemical method. The swelling behavior of grafted polymer at different pH conditions and their kinetic studies were investigated. Fourier Transform Infrared Spectroscopy (FTIR) was used to characterize the grafted polymer and the morphological structure was analyzed by Scanning Electron Microscope (SEM). As (V) ions uptake capacity of the adsorbent was evaluated in the light of varying pH, contact time, temperature, adsorbent dose, and different arsenate ion concentration. The adsorption data was fitted well in the Langmuir model and various static parameters were calculated. The removal of toxic As (V) ions was carried out by batch method using grafted sorbents synthesized by both gamma radiation and chemical grafting methods and it was observed that the adsorbent synthesized by the use of gamma radiation shows higher adsorption capacity as compared to the chemically grafted polymer.

Graphical Abstract

Keywords:

• Chitosan
• HEMA
• grafting
• adsorption
• arsenic (V)
• irradiation

Acknowledgements

The authors would like to express thanks to Radiation Technology Development Division, BARC, Mumbai, India for providing the facility to synthesize radiation grafted polymers. Authors are also grateful to Sophisticated Analytical Instruments Facility, Cochin, India for FTIR and SEM analysis.