Aniline chlorination by in situ formed Ag–Cl complexes under simulated solar light irradiation

Ag speciation in a chloride medium was dependent upon the Cl/Ag ratio after releasing into surface water. In this study, the photoreaction of in situ formed Ag–Cl species and their effects on aniline photochlorination were systematically investigated. Our results suggested that formation of chloroaniline was strongly relevant to the Cl/Ag ratio and could be interpreted using the thermodynamically expected speciation of Ag in the presence of Cl⁻. AgCl was the main species responsible for the photochlorination of aniline. Both photoinduced hole and •OH drove the oxidation of Cl⁻ to radical •Cl, which promoted the chlorination of aniline. Ag⁰ formation was observed from the surface plasmon resonance absorption during AgCl photoreaction. This study revealed that Ag⁺ released into Cl⁻-containing water may result in the formation of chlorinated intermediates of organic compounds under solar light irradiation.