Adsorptive Removal of Metanil Yellow from Aqueous Solution using SnO2 Nanoparticle: Thermodynamics, Desorption and Reusability Studies

Abstract

Adsorption studies was conducted to investigate the removal of Metanil yellow (MY) by using SnO₂ nanoparticle prepared via co-precipitation method. The adsorbent properties were analysed using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Brunauer-Emmett-Teller (BET) Analysis. Experimental factors including pH (2 – 12), time (2 – 60 minutes), adsorbent dosage (0.2 – 1.0 g), initial dye concentration (10 – 250 mg/L) and temperature (303 – 333 K), were examined for their influence
on the adsorption process. The experimental findings showed the optimal dye adsorption occurred at pH 2, 0.6 g dosage, 303 K temperature, 250 mg/L concentration and an equilibrium time of 10 minutes. The thermodynamic analysis indicated that the adsorption is feasible and spontaneous, an exothermic process with decrease in randomness. Lower values ΔG and ΔH indicated a physical adsorption process. Desorption studies shows that NaOH offered better desorption efficiency for the Dye, while reusability studies showed a good adsorbent performance even after five successive cycles. Considering the above findings, SnO₂ nanoparticle was found to
be a good adsorbent for removing dye pollutant.