Effective synthesis and application of artichoke and orange peels-based bio-sorbents for Ketoprofen removal from wastewater: Process optimization using Factorial methodology

Abstract

Two new bio-adsorbents were successfully synthesized by doping method with zinc chloride salt (ZnCl2) of raw artichoke leaves (RAL) and raw orange peels waste (ROP). Different analysis techniques (i.e. BET, SEM, XRD, FTIR) were used for characterizing the synthesized materials. Ketoprofen (KTF) nonsteroidal anti-inflammatory drug was effectively removed from water using the synthesized bio-adsorbents, under different operating conditions. The specific surface areas increased from 1009.960 and 997.816 m2/g for ROP and RAL natural materials, respectively, to 1511.278 and 3415.951 m2/g for ROP- and RAL-doped materials. More interestingly, maximum Ketoprofen removals of 90% and 96% were obtained using ROP- and RAL-doped bio-adsorbents, against null removal for natural ROP and RAL materials. The kinetic study shows that the pseudo-second order model simulated adequately the obtained Ketoprofen removal data with R2 superior to 99%. A DOE based on (23) full factorial design was used to evaluate the effect of pH, bio-adsorbent dosage and initial KTF concentration on Ketoprofen removal efficiency. The optimum conditions for KTF removal with both the activated wastes were pH= 2, bio-adsorbent dose of 0.1 g/L and C0,KTF= 5 mg/L with removal efficiency of 98.14% for ROP-ZnCl2, and pH= 2, bio-adsorbent dose of 0.3 g/L and C0,KTF = 20 mg/L with a removal efficiency of 99.84% for RAL-ZnCl2 bio-sorbent.