Adsorption of NMST from acetic acid on coconut activated carbon: Kinetics, isotherms and thermodynamics

Exploration has been made into 2-nitro-4-methylsulfonyltoluene (NMST) adsorption on coconut activated carbon from acetic acid. The results demonstrate that the adsorption of NMST on activated carbon augments with its concentration in acetic acid. NMST adsorption on activated carbon is also improved with temperature. Though NMST adsorption on per gram of carbon will decrease with carbon dosage, more NMST will be adsorbed. The kinetic study depicts that NMST adsorption on activated carbon is in good agreement with the pseudo-second-order kinetic equation. Both of the Langmuir and Freundlich equilibrium isotherm models are well fit for the experimental results, with R2 = 0.9994 and 0.9979, respectively. The adsorption thermodynamic parameters (ΔH, ΔG, ΔS) calculated with Van't Hoff equations indicate that NMST adsorption on carbon is spontaneous and endothermic.