Reaction of methylene blue with OH radicals in the aqueous environment: mechanism, kinetics, products and risk assessment.

ABSTRACT: Methylene Blue (MB) is an industrial chemical used in a broad range of applications, and hence its discharge is a concern. Yet, the environmental effects of its degradation by HO˙ radicals have not been fully studied yet. This study employs quantum chemical calculations to investigate the two-step degradation of MB by HO˙ radicals in aqueous environments. It was found that MB undergoes a rapid reaction with the HO˙ radical, with an overall rate constant of 5.51 × 10⁹ to 2.38 × 10¹⁰ M^-1 s^-1 and has a rather broad lifetime range of 11.66 hours to 5.76 years in water at 273-383 K. The calculated rate constants are in good agreement with the experimental values (k _calculation/k _experimental = 2.62, pH > 2, 298 K) a

SUBMITTER: Vo QV 

PROVIDER: S-EPMC11348493 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature