Fixed-bed adsorption of Pb() and Cu() from multi-metal aqueous systems onto cellulose--hydroxyapatite granules: optimization using response surface methodology

• Published in: RSC advances Vol. 13; no. 45; pp. 31935 - 31947
• Main Authors: Marrane, Salah Eddine, Dânoun, Karim, Essamlali, Youness, Aboulhrouz, Soumia, Sair, Said, Amadine, Othmane, Jioui, Ilham, Rhihil, Abdallah, Zahouily, Mohamed
• Format: Journal Article
• Published: 01.11.2023
• DOI: 10.1039/d3ra04974d

We prepared cellulose microfibrils- g -hydroxyapatite (CMFs- g -HAP N (8%)) in a granular form. We evaluated the ability of these granules to eliminate Pb( ii ) and Cu( ii ) ions from aqueous solution in dynamic mode using a fixed-bed adsorption column. Several operating parameters (inlet ion concentration, feed flow rate, bed height) were optimized using response surface methodology (RSM) based on a Doehlert design. Based on ANOVA and regression analyses, adsorption was found to follow the quadratic polynomial model with p < 0.005, R 2 = 0.976, and R 2 = 0.990, respectively, for Pb( ii ) and Cu( ii ) ions. Moreover, three kinetic models (Adams-Bohart, Thomas, Yoon-Nelson) were applied to fit our experimental data. The Thomas model and Yoon-Nelson model represented appropriately the whole breakthrough curves. The Adams-Bohart model was suitable only for fitting the initial part of the same curves. Our adsorbent exhibited high selectivity towards Pb( ii ) over Cu( ii ) ions in the binary metal system, with a maximum predicted adsorption capacity of 59.59 ± 3.37 and 35.66 ± 1.34 mg g −1 , respectively. Under optimal conditions, multi-cycle sorption-desorption experiments indicated that the prepared adsorbent could be regenerated and reused up to four successive cycles. The prepared CMFs- g -HAP N was an efficient and effective reusable adsorbent for removal of heavy metals from aqueous systems, and could be a suitable candidate for wastewater treatment on a large scale. Prepared CMFs- g -HAP N was an efficient and effective reusable adsorbent for removal of heavy metals from aqueous systems, and could be a suitable candidate for wastewater treatment on a large scale.