Reduction of Methylene Blue by Ascorbic Acid: Kinetic and Thermodynamic Aspects

This article reports the reduction of methylene blue (MB) by ascorbic acid (H2As) in basic aqueous and micellar solutions. Ascorbate ion (As2-) is found to be an effective reducing agent for the decolorization of methylene blue under ambient condition. Effects of salting-in and salting-out agents have been investigated for real-time application in the reduction process. The salting-in agent urea has been found to uniquely enhance the rate of the reduction of MB by As2- in the presence of micelles. Detailed kinetic and thermodynamic aspects have been considered to realize the interaction between methylene blue and ascorbate ion. Kinetic studies revealed that the reaction follows pseudo first order reaction kinetics.