title: Removal of isopropyl alcohol and methanol in ultrapure water production system using a 185 nm ultraviolet and ion exchange system.
abstract: The oxidation of low-molecular-weight (LMW) compounds, including isopropyl alcohol (IPA) and methanol in ultrapure water (UPW) production system was evaluated using the continuously operating 185 nm total organic carbon (TOC) reduction UV and ion exchange system. The initial concentration of compounds was in the range of tens of ppb which was the general feed condition of UV system located after 2 pass reverse osmosis (RO) in the UPW production system. UV irradiation transformed the compounds to less oxidative products that were ultimately converted to CO2. The ion exchange system then removed carboxyl-containing organic acids generated by UV oxidation. It means that the oxidation efficiency of organic compounds by UV irradiation can be accurately measured by the summation of the final product (CO2) and the by-product containing carboxyl functional group. The removal efficiency of LMW compounds decreased when either the initial TOC concentration increased or the UV intensity was reduced. Finally, the insertion of a baffle into the UV oxidation system was found to enhance solution turbulence and improve the oxidation efficiency.
authors.affiliation: R&D Center, Samsung Engineering Co. Ltd, 415-10 Woncheon-Dong, Youngtong-Gu, Suwon, Gyeonggi-Do, 443-823, South Korea.
authors.forename: Jeongyun
authors.initials: J
authors.lastname: Choi
authors.affiliation: Department of Civil and Environmental Engineering, Hanyang University, 222 Wangsimni-Ro, Seongdong-Gu, Seoul, 133-791, South Korea.
authors.forename: Jong-Oh
authors.initials: JO
authors.lastname: Kim
authors.affiliation: R&D Center, Samsung Engineering Co. Ltd, 415-10 Woncheon-Dong, Youngtong-Gu, Suwon, Gyeonggi-Do, 443-823, South Korea. Electronic address: chung.j@samsung.com.
authors.forename: Jinwook
authors.initials: J
authors.lastname: Chung
mesh_terms: D019840:2-Propanol / Q000737:chemistry* / Q000528:radiation effects; D005374:Filtration; D007474:Ion Exchange; D000432:Methanol / Q000737:chemistry* / Q000528:radiation effects; D010084:Oxidation-Reduction; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000528:radiation effects; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
chemical_list: D014874:Water Pollutants, Chemical; D019840:2-Propanol; D000432:Methanol
keywords: Isopropyl alcohol (IPA); Low-molecular-weight compounds; Methanol; TOC-UV; Ultrapure water (UPW)