Application of magnetic nanocomposite of multi-walled carbon nanotube for removal of Direct Green 26 dye from aqueous solutions: Response surface modeling and kinetic studies

In this study, magnetic nanocomposite of multi-walled carbon nanotube (mMWCNT) was used as adsorbent for removal of Direct Green 26 (DG26) dye. Process optimization was performed using the response surface modeling method based on the Box-Behnkenn experimental design. Adsorbent dosage (1-3 g L-1), pH (2.5-8.5) and contact time (25-45 min) were considered as the experimental variables and dye removal efficiency as the response. Results of the regression analysis showed good fit of the experimental data of dye removal process to a quadratic model with coefficient of multiple determination of 0.9824 and p