Kinetics and mechanism of As2S2 oxidation

Abstract

The kinetics of realgar (As2S2) oxidation was studied under isothermal and non-isothermal conditions. The obtained values of the activation energy indicate that the process occurs in the kinetic domainwith the realgar particles being converted to As2O3 and As4O6 (g). The very fast reaction rates were limited by the chemical reaction. The kinetic equation was found to be: –ln (1–α) = 4.56 x 103 x e(–8780/T) x t. The proposed reaction mechanism and chemical transformation investigated by ICP–AES, EDXRF and thermal analysis are discussed.

Keywords

• thermal analysis
• activation energy
• as2s2
• edxrf
• icp–aes.