Treatment of malachite green dye containing solution using bio-degradable Sodium alginate/NaOH treated activated sugarcane baggsse charcoal beads: Batch, optimization using response surface methodology and continuous fixed bed column study

Abstract

In this study, carbonized material was produced using sodium hydroxide treated Sugar cane bagasse (SB), and synthesized materials ware used to prepare Sodium Alginate/SBAC composite beads which were further used as an adsorbent to remove malachite green dye (MG) present in water. Physiochemical characteristics of composite beads were analyzed using FTIR, SEM, TGA, and BET. Adsorption equilibrium data showed excellent fit to the Freundlich model (R2 = 0.994) than to the Langmuir model (R2 = 0.925). Adsorption kinetics study indicated that the MG removal process would be better described by the pseudo-second-order kinetic model. The thermodynamic study suggested the spontaneous and endothermic nature of MG adsorption. By using response surface methodology, the optimum conditions for MG adsorption on composite beads were found to be 115.43 min, 0.3 g/L and pH 8 for contact time, adsorbent mass, and pH respectively and MG adsorption efficiency was 97.88%. The fixed-bed column data were evaluated using several kinetic models and among them, Thomas model showed the best agreement with investigation results. These results revealed that synthesized composite beads have a high affinity toward MG and it could be reasonable, eco-friendly adsorbent for dye removal from wastewater.