An Investigation on Performance of Chitosan/Carbon Nanotube Composite for Adsorption of Diazinon from Agricultural Wastewater

In recent years, water pollution and pesticide residues in food chain have become a serious environmental problem. Therefore, it is essential to remove pesticides in water treatment. In this study, adsorption of diazinon by chitosan/carbon nanotube (CHN-CNT) adsorbent was investigated.
A protected crosslinking method was used to synthesize CHN-CNT with various ratios of carbon nanotube to chitosan. Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) were used to investigate morphological changes and chemical structure of the prepared adsorbent. Tests were done to evaluate the effects of adsorbent concentration, diazinon concentration, and contact time on adsorption of diazinon by CHN-CNT.
Findings: CHN-CNT removed diazinon from aqueous solution to a great extent. By an initial diazinon concentration of 50 mg/l, CHN-CNT concentration of 0.5 g/l, and contact time of 65 minutes, the adsorption capacity (qe) reached to 59 mg/g adsorbent. Regeneration process of the adsorbent was performed with four cycles. The efficiency recovery was obtained as 94.9% in fourth cycle.
CHN-CNT, due to being easier to prepare, high performance in adsorption, and simple and effective regeneration capacity, could be an appropriate adsorbent to eliminate the pesticide from contaminated water source.