Pan Huimei, Li Boqiang, Yang Jie, Liu Wenzhe, Luo Wang, Chen Baiyang
State Key Laboratory of Urban Water Resource and Environment, Shenzhen Key Laboratory of Organic Pollution Prevention and Control, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China.
State Key Laboratory of Urban Water Resource and Environment, Shenzhen Key Laboratory of Organic Pollution Prevention and Control, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China.
J Hazard Mater. 2023 Oct 15;460:132423. doi: 10.1016/j.jhazmat.2023.132423. Epub 2023 Aug 28.
This study revisited a list of inorganic iodine species on their detections and conversions under different water conditions. Several surprising results were found, e.g., UV-vis spectrophotometry is the only reliable method for I and I determinations with coexisting I/IO/IO, while alkaline eluent of IC and LC columns can convert them into I completely; IO can be converted into IO completely in IC columns and partly in LC columns; a small portion of IO was reduced to I in LC columns. To avoid errors, a method for detecting multiple coexisting iodine species is suggested as follows: firstly, detecting I and I via UV-vis spectrophotometry; then, analyzing IO (> 0.2 mg/L) through LC; and lastly, obtaining I and IO concentrations by deducting I and IO measured by IC from the signals derived from I/I/IO. As for stability, I or IO alone is stable, but mixing them up generates I or HOI under acidic conditions. Although IO is stable within pH 4.0-8.0, it becomes HIO/HIO in strongly acidic/alkaline solutions. Increasing pH accelerates the conversions of I and I into I under basic conditions, whereas dissolved oxygen and dosage exert little effect. Additionally, spiking ICl into water produces I and IO rather than HIO.
