Economical Adsorbent Developed from Sugarcane Bagasse for Zinc (II) Removal from Wastewater

• Published in: Water, air, and soil pollution Vol. 233; no. 8
• Main Authors: Genet, Melkamu Birlie, Jembere, Addis Lemessa, Tafete, Gedefaw Asmare
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.08.2022; Springer Nature B.V
• Subjects: Activated carbon; Adsorbents; Adsorption; Aqueous solutions; Atmospheric Protection/Air Quality Control/Air Pollution; Bagasse; Climate Change/Climate Change Impacts; Design of experiments; Differential thermal analysis; Earth and Environmental Science; Efficiency; Enthalpy; Entropy; Environment; Environmental monitoring; Experimental data; Experimental design; Free energy; Functional groups; Gibbs free energy; Heavy metals; Hydrogeology; Isotherms; Kinetics; Mathematical models; Metal concentrations; Parameters; Process parameters; Removal; Soil Science & Conservation; Sugarcane; Thermodynamic properties; Wastewater; Wastewater treatment; Water Quality/Water Pollution; Zinc; Zinc (II); Adsorption; Activated carbon; Heavy metal; Sugarcane bagasse
• ISSN: 0049-6979; 1573-2932
• DOI: 10.1007/s11270-022-05770-y

Sugarcane bagasse activated carbon (SBAC) was used as an environmentally friendly adsorbent for the removal of zinc (II) heavy metal from aqueous solutions at neutral pH. Zinc (II) adsorption efficiency was evaluated at different process parameters including adsorbent dosage, contact time, and temperature using general factorial as an experimental design to evaluate the maximum adsorption efficiency. The synthesized SBAC was subjected to advanced characterization techniques that include FTIR, XRD, and TGA/DTA to study the functional groups, crystallinity, and thermal property, respectively. Chemically modified SBAC was able to reduce initial metal concentrations by 82.4%. The optimized process parameters that give maximum removal efficiency were obtained at 40 min, 6 gm, and 60 °C. The experimental data were fitted to Langmuir, Freundlich, and Temkin models. Pseudo-first-order, pseudo-second-order, and intraparticle diffusion models were used to model adsorption kinetics. The experimental data were best fitted to the pseudo-second-order kinetic model with Langmuir isotherm. An important parameter from the isotherm which indicates adsorption capacity was 426.64 mg/g. The thermodynamic parameters for entropy, ΔS, enthalpy, ΔH, and the Gibbs free energy, ΔG, reveal that the adsorption of zinc (II) by the SBAC is endothermic, thermodynamically feasible, and a spontaneous process. Graphical abstract