%0 Journal Article
%T Fast Degradation of Monochloroacetic Acid by BiOI-Enhanced UV/S(IV) Process: Efficiency and Mechanism
%J Catalysts | An Open Access Journal from MDPI
%D 2019
%R https://doi.org/10.3390/catal9050460
%X Iodide ( I £¿ ) could promote ultraviolet-activated S(IV) processes (UV/S(IV)) and degrade aqueous halogenated organic compounds and hazardous oxoanions. With the interest of promoting use of this technology, this study investigated the feasibility of using bismuth oxyiodide (BiOI) as an I £¿ source to enhance UV/S(IV) where monochloroacetic acid (MCAA) was selected as a testing model compound. Degradation of MCAA by UV/S(IV) increased by 50% in presence of BiOI. Results of competitive kinetics indicated that the promotion effect brought by BiOI mainly originated from its sustainable release of I £¿ , and subsequent enhanced generation of hydrated electrons. Electron spin resonance detection and fluorescence characterization proved increased formation of sulfite radical, resulting from sulfite oxidation by UV-excited BiOI. However, the sulfite radical only made a small contribution (9%) to MCAA degradation due to its moderate reactivity toward MCAA (4.2 ¡Á 10 5 M £¿1¡¤s £¿1). UV/S(IV) combined with BiOI significantly decreasing the biotoxicity of MCAA solution. BiOI can be regenerated using I £¿ -containing solution. Our findings provide evidence that BiOI is a promising I £¿ source and photocatalyst, which progresses the I £¿ -assisted UV/S(IV) process towards practical application. View Full-Tex
%U https://www.mdpi.com/2073-4344/9/5/460