Adsorptive removal of nickel ions from wastewater by synthesized a novel biocomposite material and process optimization by response surface methodology

In the present study, a fixed-bed column study was performed using a novel biocomposite mate-rial, Amanita vaginata immobilized on Amberlite XAD-4 resin, to find out the adsorption behavior of nickel (Ni2+) ions from industrial wastewater. The influence of some important operating conditions including pH (3–7), biocomposite material amount (150–250 mg (XAD-4:Amanita vaginata, 5:1)) influent flow rate (4–8 mL min–1) besides Ni2+ ions initial concentration (20–40 mg L–1) on the uptake of Ni2+ solution were also optimized using a synthetic water solution. A central composite design combined with response surface methodology was utilized to maximize Ni2+ ions removal using A. vaginata immobilized on Amberlite XAD-4 resin as a biocomposite material in a column biosorption process. A mathematical model was derived from the central composite design approach for predicting responses and analysis of variance. Also, for checking model adequacy a lack of fit test was carried out. It was determined that the checked and proposed quadratic model was derived from the experimental design data. The biocomposite material adsorption capacity was calculated as 6.28 mg g–1. A high coefficient of determination (R2 = 0.9887) was presented by analysis of variance. Results confirmed that the amount of adsorbed Ni2+ amount did not change with the increase of the flow rate ratio and dose when the initial concentration of Ni2+ ions increased. The maximum adsorp-tion capacity of biocomposite material was achieved at 6.9 pH, 150.1 mg of biocomposite material amount, 7.8 mL min–1 of solution flow rate, and 39.7 mg L–1 of Ni2+ ions initial concentration. Finally, the developed method was applied to industrial wastewater to determine Ni2+ ions concentrations.