Study on adsorptive removal of carmoisine azo dye from aqueous solution using the modification of activated carbon from rubber fruit shells and its magnetic composite

A Carmoisine azo dye was removed through the modification of activated carbon from rubber fruit shells (AC-RFs) and its magnetic composite (MC). While adsorbents were synthesised using the co-precipitation method, the surface characteristics of activated carbon obtained from rubber fruit shells (AC-RFs) and magnetic composites (MC) were characterised using XRD, FTIR, XPS, TGA-DTA, DLS, VSM, UV-Visible, Raman spectra, HR-TEM, AFM, FE-SEM & EDAX, and SEM methods. In batch experimental mode, the ideal conditions for carmoisine azo dye uptake were a contact time of 180 min. temperature of 25°C, and pH 3 for the adsorbents AC-RFs and MC, respectively. The effect of surfactants, metals, and salt content on biosorption capacity was also examined. Kinetic studies showed that the pseudo-second-order kinetic model well followed the experimental data. Langmuir isotherm and Temkin isotherm showed well fit for AC-RFs/MC adsorbent, with the maximum adsorption capacity for AC-RFs/MC adsorbents being 2732.11 mg/g at 25°C. After 180 min. of dye agitation, a removal rate of close to 99.9% was examined. The findings showed that 30 mg of adsorbent, with 180 min. and a pH range of 2–4 was the optimum condition for maximum dye removal efficiency onto AC-RFs/MC. A thermodynamic study on carmoisine azo dye showed endothermic and consistent biosorption onto AC-RFs and MC. The study examined the effect of bed height and concentration under a constant flow rate. Kinetic models BDST (bed depth service time) and Thomas were utilised using column experimental data. This research indicates that magnetic biocomposites synthesised from activated carbon from rubber fruit shell biomass exhibit significant adsorbent properties for the removal of carmoisine azo dye from aqueous solutions.