Photochlorination of bisphenol A by UV-Vis light irradiation in saline solution: effects of iron, nitrate and citric acid

Environmental context Chlorinated organic compounds are ubiquitous in the environment, and cause concern owing to their persistence and toxicity to organisms. In addition to anthropogenic sources, photochemical processes in saline waters could also yield chlorinated organic compounds. The present paper investigates the effects of iron, pH, nitrate and dissolved organic matter on the photochlorination of bisphenol A, a widely distributed endocrine disrupting chemical. Abstract Effects of several key influencing factors of environmental photochemistry, including iron, nitrate and dissolved organic matter (DOM), on the photochlorination of bisphenol A (BPA) were investigated. Iron promoted the formation of chlorinated BPA, but the rate decreased with increasing pH. This result was consistent with the results of laser flash photolysis, which showed that high pH decreased the formation of reactive chlorine species (chlorine radical, Cl•/Cl2•–). Nitrate ion and citric acid, which was selected as an analogue of DOM, inhibited the chlorination of BPA separately. The results presented in this paper are helpful to get some idea of the degree of photochemical chlorination in aqueous environment.