Park G, Yu M, Go J, Kim E, Kim H
The University of Seoul, Dept. of Environmental Engineering, 90 Jeonnong-dong, Dongdaemun-gu, Seoul 130-743, South Korea.
Water Sci Technol. 2007;55(5):117-25. doi: 10.2166/wst.2007.170.
Among the chemicals causing taste and odour (T&O) in drinking water, the most commonly identified and problematic ones are geosmin and 2-MIB (2-methylisoborneol). Since the reported odour thresholds of geosmin and 2-MIB are as low as 4 and 8.5 ng/L, respectively, they are not readily removed by conventional water treatment processes. In this study, ozone (O3) and ferrate (Fe(VI)) were applied to oxidise geosmin and 2-MIB. Their performances were compared in terms of removal efficiency of geosmin and 2-MIB. In the case of O3, removal efficiency of geosmin and 2-MIB ozonation at different initial O3 doses, H2O2/O3 ratios and water temperatures were evaluated. The oxidation rates of geosmin and 2-MIB by Fe(VI) were measured within pH 6-8. The effect of H2O2 addition was also evaluated. In summary, O3, especially with H2O2, could almost completely oxidise geosmin and 2-MIB, while Fe(VI) could not oxidise them more than 25% at any pH that was considered in this study. This was attributed to the structure of the organics and high reaction selectivity of Fe(VI). Further study should be conducted to find the reason of inhibition of oxidation by Fe(VI).
在导致饮用水出现味觉和嗅觉问题（T&O）的化学物质中，最常被识别且成问题的是土臭素和2-甲基异莰醇（2-MIB）。由于据报道土臭素和2-甲基异莰醇的气味阈值分别低至4纳克/升和8.5纳克/升，它们不易被传统水处理工艺去除。在本研究中，采用臭氧（O₃）和高铁酸盐（Fe(VI)）来氧化土臭素和2-甲基异莰醇。从土臭素和2-甲基异莰醇的去除效率方面对它们的性能进行了比较。对于臭氧，评估了在不同初始臭氧剂量、过氧化氢/臭氧比例和水温下土臭素和2-甲基异莰醇的臭氧氧化去除效率。测定了在pH值6 - 8范围内高铁酸盐（Fe(VI)）对土臭素和2-甲基异莰醇的氧化速率。还评估了添加过氧化氢的影响。总之，臭氧，尤其是与过氧化氢一起使用时，几乎可以完全氧化土臭素和2-甲基异莰醇，而在本研究考虑的任何pH值下，高铁酸盐（Fe(VI)）对它们的氧化率都不超过25%。这归因于有机物的结构和高铁酸盐（Fe(VI)）的高反应选择性。应进一步开展研究以找出高铁酸盐（Fe(VI)）氧化受抑制的原因。
