Magnetic chitosan nanocomposite: Fabrication, properties, and optimization for adsorptive removal of crystal violet...

Recovery of crystal violet (CV) dye was investigated using magnetic chitosan nano-composites (MCNCs) and the effects of process variables (contact time, initial CV concentration, adsorbent dose, and pH) were optimized through response surface methodology. The reliability of the RSM models (first-order model, first model with interaction, the second-order model, and reduced model) was tested by fitting the data. A comparative analysis of the results derived from the models demonstrated that the reduced model was the best. According to modelling results, MCNCs dosage and contact time were found to be the most effective variables on the adsorption efficiency procedure, respectively. Also, pH had no significant effect on the adsorption uptake statistically. MCNC has the maximum adsorption efficiency (72%) when the contact time, adsorbent dosage, and initial concentration of CV were optimally set as 140 min, 1 g, and 77 mg/L, respectively. Quantity uptake of CV was evaluated using the Langmuir, Freundlich, and Temkin models. Based on findings, Freundlich isotherm fitted well with the experimental results. Kinetic studies showed that the pseudo-first-order model fitted the best the experimental data, which indicated that the adsorption rate of CV molecules onto MCNC was time-dependent. The studies on the well regenerability of MCNC in addition to its high potentiality of cationic dyes removal make it an attractive adsorbent in terms of dye-containing wastewaters treatment.