Removal of iopromide and degradation characteristics in electron beam irradiation process.
The aim of this study is to evaluate the removal efficiency of iopromide using electron beam (E-beam) irradiation technology, and its degradation characteristics with hydroxyl radical (OH) and hydrated electron (e(aq)(-)). Studies are conducted with different initial concentrations of iopromide in pure water and in the presence of hydrogen peroxide, bicarbonate ion, or sulfite ion. E-beam absorbed dose of 19.6 kGy was required to achieve 90% degradation of 100 μM iopromide and the E-beam/H(2)O(2) system increased the removal efficiency by an amount of OH· generation. In the presence of OH scavengers (10 mM sulfite ion), the required dose for 90% removal of 100 μM iopromide was only 0.9 kGy. This greatly enhanced removal was achieved in the presence of OH· scavengers, which was rather unexpected and unlike the results obtained from most advanced oxidation process (AOP) experiments. The reasons for this enhancement can be explained by a kinetic study using the bimolecular rate constants of each reaction species. To explore the reaction scheme of iopromide with OH· or e(aq)(-) and the percent of mineralization for the two reaction paths, the total organic carbon (TOC), released iodide, and intermediates were analyzed.
Department of Environmental Engineering (YIEST), Yonsei University, Heungup, Wonju, Republic of Korea.
Minhwan
M
Kwon
Yeojoon
Y
Yoon
Eunha
E
Cho
Youmi
Y
Jung
Byung-Cheol
BC
Lee
Ki-Jung
KJ
Paeng
Joon-Wun
JW
Kang
D001639:Bicarbonates / Q000737:chemistry; D003287:Contrast Media / Q000737:chemistry / Q000528:radiation effects*; D004583:Electrons; D006861:Hydrogen Peroxide / Q000737:chemistry; D017665:Hydroxyl Radical / Q000737:chemistry; D007455:Iodine / Q000737:chemistry; D007472:Iohexol / Q000031:analogs & derivatives* / Q000737:chemistry / Q000528:radiation effects; D013447:Sulfites / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000528:radiation effects*; D018508:Water Purification / Q000379:methods*
D001639:Bicarbonates; D003287:Contrast Media; D013447:Sulfites; D014874:Water Pollutants, Chemical; D017665:Hydroxyl Radical; D007472:Iohexol; C038192:iopromide; D007455:Iodine; D006861:Hydrogen Peroxide