Design Expert Application in the Optimization of Cadmium (II) by Chitosan from Produced water

Abstract

Oil and gas industry generates by-products in large quantities and is known as produced water. It contains highly immiscible oil, grease, dissolved hydrocarbons, heavy metals, and other pollutants. Globally, produced water volume has increased and became the largest waste stream and requires remediation. Adsorption provides better removal efficiency for metals removal than any other techniques. The present study aimed to remove Cadmium (II) by using chitosan as an adsorbent.  The response surface methodology (RSM) module in the software“Design-Expert® involving central composite design (CCD) was employed to optimize independent variables to achieve maximum ion removal. The effect of metal ion concentration, adsorbent dosage, contact time, and pH were analyzed empirically and successfully by RSM. Cd (II) in produced water represents a significant environmental and human health risk due to its high toxicity and bioaccumulation potential. Statistically significant quadratic polynomial for Cd (II) was obtained via regression analysis R2 (0.94). The highest removal efficiency, 89.45% was attained under the optimized conditions.