Degradation of methyl orange catalysed by Pt/Al₂O₃ in aqueous medium

Azo dyes are rebellious and mulish pollutants which contribute a momentous anxiety on the environment. This report is focused on of Pt/Al₂O₃ catalysed the degradation treatment of methyl orange which is a water soluble azo dye. Experimental variables like temperature, speed of agitation, catalyst dosage, initial concentration of dye and reusability of catalyst were investigated systematically. It was noted that rise in temperature enhances the degradation efficiency and increase in initial concentration decreases the degradation. Batch experimental data at various temperatures were subjected to kinetic analyses. Curve Expert software was used for kinetics analyses. The kinetics analyses indicated that degradation reaction follow Langmuir-Hinshelwood mechanism. Activation energy, entropy, enthalpy of adsorption and Gibbs free energy were calculated as 29 kJ mol^-1, 94.9 J K^-1 mol^-1,-18.2 kJ mol^-1, and-10.6 kJ mol^-1, respectively.