Removal of malachite green, a cationic textile dye using Amberlite polymeric resins

ABSTRACT

Malachite green dye was removed using three different polymeric resins (Amberlite XAD7, Amberlite 120H and Amberlite IRA67). Equilibrium and kinetic experiments were carried out to determine the effect of contact time (0–120 min), resin dose (0.05–0.4 g), initial dye concentration (10–50 mg/L), temperature (303–323 K), pH (2–12) and NaCl concentration (0.5–50 g/L) on the adsorption capacity of all the resins. With an increase in the resin amount, a sharp decrease in the adsorption capacity was observed. The removal efficiency of dye was found to be 98.29% with IRA67, 99.27% with XAD7, and 98.66% with IR120H after 120 min. Temkin isotherm matched equilibrium data for XAD7 and IR120H, whereas Freundlich isotherm model best described the results for IRA67, pH, temperature and NaCl did not affect the removal efficiency significantly. Kinetic data were well fitted with pseudo-second order rate kinetics. All the three resins were regenerated using 1 M NaOH solution showing good reusability.

KEYWORDS:

• Malachite green
• Amberlite resin
• adsorption
• kinetic
• equilibrium

Disclosure statement

No potential conflict of interest was reported by the author(s).