| Taste and odor (T&O) problem is a key problem of drinking water treatment allover the world. Eutrophication of reservoir water and lake water has made the T&O problem more serious. At the same time, traditional drinking water treatment is not efficient for solving T&O problem. Though many strategies of drinking water treatment have been carried out to solve T&O problem, there are still many blemishes for application in water treatment, such as weak removal efficiency, residual oxidant, and higher cost. So exploring new advanced drinking water treatment for resolving T&O problem is very important.Due to problems emerged in resolving water taste and odor problems by ozonation, invesgitation ofγ-Al2O3 catalyzed ozonation for 2-methylisoborneol, (MIB) removal was carried out. Then, takenγ-AlOOH,γ-Al2O3, andα-Al2O3 as catalysts, the rule of aluminum oxides catalyzed ozone decomposition was investigated. By choosing MIB and 2,4,6-Trichloroaminsole (TCA) as the target compounds, the mechanism of aluminum oxide catalyzed ozonation was discussed. Finally, using natural bauxite as raw material, the catalyst which was efficient to remove both MIB and TCA was prepared through a simple heat treatment.Removal efficiency and mechanism of MIB by ozonation was investigated. Disadvantageous of ozonation MIB was investigated widely. Both ozone molecule and hydroxyl radicals were account for MIB degradation. By GC-MS analysis, it was speculated that d-camphor was a main product of ozonation MIB. A speculated degredation pathway was presumed. On the basis of efficiency and mechanism investigation, there were some problems in ozonation process for MIB degradation.The efficiency and the mechanism of catalyzed ozonation MIB in present ofγ-Al2O3 were carried out. The efficiency of removal MIB was enhanced remarkably byγ-Al2O3. According to inhibiting experiment and ESP analysis, it was specluted that hydroxyl radicals was the acitivity species. Yield of hydroxyl radicals was much higher than that of ozonation alone. Effect of solution pH and anions confirmed surface hydroxyl groups was the activity site for catalyzed ozonation withinγ-Al2O3. To discussing the mechanism of catalyzed ozonation within aluminum oxides, experiments of aluminum oxides (γ-AlOOH,γ-Al2O3,α-Al2O3) catalyzed ozone decomposition were carried out. Aluminum oxides could enhance ozone decomposition. Based on inhibit of hydroxyl radicals experiments and yield of hydroxyl radical, aluminum oxide could enhance ozone decomposition to form hydroxyl radicals. According to effect of solution pH and anion adsorption on catalyzed ozonation, it was confirmed that surface hydroxyl groups was the active site. Br?nsted acidity of aluminum oxide was relationship with catalyzed ozone decomposion.Role of aluminum oxide catalyzed ozonation for MIB and TCA was investigated. Effects of crystal and surface property of aluminum oxide on catalyzed ozonation MIB and TCA were discussed. Efficiency of three aluminum oxides catalyzed ozonation was different. On the basis of quantitative analysis oxidant contribution in catalyzed ozonation, formation of hydroxyl radicals was account for highest catalytic activity ofγ-Al2O3 in oxidation MIB, ozone molecule oxidation was account for lowest catalytic activity ofγ-AlOOH. In the processes of catalyzed ozonation TCA, oxidation of hydroxyl radicals was account for TCA degradation. According to effect of solution pH on catalyzed ozonation, it was confirmed that surface hydroxyl groups was the catalytic active site. Adsorption actions of T&O compounds on aluminum oxides were investigated. It was concluded that MIB was adsorbed on aluminum oxides by surface hydroxyl radical, and TCA was adsorbed on aluminum oxides by physical adsorption. Surface hydroxyl groups was not only the activity site for adsorption of MIB onγ-AlOOH, but also the catatic acitivity site for degradation MIB by catalyzed ozonation process in present of aluminum oxides. Adsorption actions of MIB onγ-AlOOH inhibited the catalytic activity in catalyzed ozonation process.Simple thermal treatment for origin bauxite, made origin materal possessed surface properties of bothγ-AlOOH andγ-Al2O3. Bauxite450 exhibited remarkable catalytic activity in degradation MIB and TCA. By inhibiting experiments of hydroxyl radicals and Rct quantitative determination, Bauxite450 catalytzed ozone decomposition and enhanced field of hydroxyl radicals.
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