| This paper mainly studies oxidation characteristics by hydroxyl peroxide with Mn2+ Cu2+ Fe2+ #O3 as catalyst on aquatic natural organic matters(NOM)- humic acid(HA), and oxidation by ozone oxidation by hydroxyl peroxide and so the effects of pre-oxidation for direct organic removal and on the treatability of organic matters by subsequent coagulation and granular activated carbon adsorption were also studied, also analyze on macromolecules and the structure of natural humic acids using HPLC and pyrolysisGC-MS techniques.The result show that, oxidation by hydroxyl peroxide with Mn2+ Cu2+ Fe2+and O3 as catalyst on aquatic natural organic matters(NOM) humic acid(HA) can more result in direct removal of color and UV254 Among these catalyst, Fe2+ and O3 seems to be the most effective to remove UV254, The result implies that organic molecules with unsaturated structure are often more UV-sensitive than those with saturated structure and alter the structure of the organic molecules. The HPLC and pyrolysis GC-MS analysis was applied to identify the main functional groups of the HA before and after pre-oxidation by hydroxyl peroxide with Mn2+ Cu2+ Fe2+ and O3 as catalyst. The result show that, the dominant functional groups detected from the raw water (HA solution) are cyclic hydrocarbons and aromatics,such as benzoaldehyde, cyclohexanone,benzene tricarboxylic acid, benzophenone etc, while after oxidation by ozone or H2O2 with ozone, many of these cyclic hydrocarbons are no longer in existence and many chain hydrocarbons and aliphatic acids with oxygenated groups such as carboxyl,hydroxyl,ketone,ether,ester etc are newly formed. Apparently the organic functional groups undergo a significant change in their structure, mostly from cyclic to chain hydrocarbons and/or from aromatics to aliphatics. This process is also accompanied by a decrease in the molecular weight of the HA as is demonstrated by the HPLC analysis results which show a disappearance or decrease of the peaks in the range of MW larger than 500 Dalton and an increase of the peaks in the smaller MW range in the liquid chromatogram. the effect of pre-oxidation on the overall removal of CODMn and TOC can be much improved than oxidation by ozone.The effect of pre-oxidation on the overall removal of CODMnand TOC as coagulation (aluminum sulfate as coagulant and at pH 5.0) or GAC adsorption is subsequently applied. Pre-oxidation can apparently improve the CODMn and TOC removal,especially under the condition of pre-oxidation by ozone or H2O2 with ozone. Aliphatic groups such as carboxyl and hydroxyl groups are believed to be more readily to react with alum to form Al-humic complexes which result in better coagulation.Because pre-oxidation brings about an increase in the portion of aliphatic groups, the HA molecules in the solution become more coagulable with aluminum coagulant. For GAC adsorption, the molecular weight of the organic matters is an important factor. As discussed above, larger organic matters can be broken into smaller ones by pre-oxidation. This makes the organic matters more favorable to be adsorbed by GAC.The result of this study also indicates that H2O2 only is not very effective for pre-oxidation but its function can be much improved with certain chemicals as catalysts.ozone and its function is mainly to alter the structure of organic matters so that their removal can be much improved for the subsequent treatment. In this case, ozone is found to be the best catalyst. A small dose of ozone can assist H2O2 to attain a TOC removal of 50% and UV254 removal of 70% directly, and the treatability of organics by subsequent treatment can be further improved by analyzing with color, UV254 TOC, CODMn , HPLC GC-MS et al.lt show that oxidation characteristics and mechanism by hydroxyl peroxide with Mn2+, Cu2+ Fe2+ and O3 as catalyst on aquatic natural organic matters(NOM)- humic acid(HA), and oxidation by ozone, oxidation by hydroxyl peroxide and so the effects of pre-oxidation for direct organic removal and on the treatability of organic m...
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