典型卤代苯酚在 Na₂SO₃/UV 体系中的还原降解与脱卤

Halogenated organic compounds threaten ecological environment and public health due to their high toxicity and stability. The current technology such as oxidation processes is still challenged by the low efficiency in dehalogenation and the resulting risks of highly toxic intermediates. Through selecting eleven halophenols as target compounds，this study investigated the reductive degradation kinetics and dehalogenation efficiency in the sulfite/UV process，and revealed the dependence on molecular structure，including halogen type，substitution position，and halogenation degree. The results indicated that halophenols underwent fast direct photolysis under UV irradiation，and the removal kinetics and dehalogenation efficiency could be significantly enhanced by the powerfully reducing species in the sulfite/UV process，depending on the structure of halophenols. Bromophenols and iodophenol showed higher reduction efficiency than chlorophenols. The halogen substitution positions influenced the removal kinetics and dehalogenation efficiency following the descending order of para- > ortho- > meta-，and higher halogenation degree also favored the removal kinetics and dehalogenation in the process. This study gives insight into the reductive degradation of halogenated organics，and thus provides a novel technique for safe removal of refractory and toxic pollutants.