Raw mineral bauxites with and without thermal treatment were used as catalysts in a catalyzed ozonation process for the degradation of a typical taste and odour compound 2-Methylisoborneol (MIB). Compared with the sole ozonation or catalyst adsorption, raw mineral bauxite without further thermal treatment did not exhibit remarkable catalytic activity. But all bauxite catalysts with further thermal treatment exhibited some catalytic activity. Changing of the crystalline form during the thermal treatment played an important role in enhanced ozonation efficiency.Bauxite calcined at 4508C (Bauxite450), which is composed of g-Al 2 O 3 , exhibited the most remarkable catalytic activity among all the bauxite catalysts with thermal treatment. Catalyzed ozonation with Bauxite450 could remove MIB effectively and reduce MIB concentration to below its taste and odour threshold concentration. The catalyzed ozonation of MIB followed an indirect oxidation mechanism by hydroxyl radical ( z OH). This result was confirmed by tert-butyl alcohol inhibiting the catalytic activity and R ct value between the sole ozonation and catalyzed ozonation.As a natural mineral catalyst, bauxite with thermal treatment has supplied an economical and feasible choice for the catalyzed ozonation of MIB in drinking water.

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Utilization of textile-related wastes is investigated for the growth of substance-circulating society and the establishment of recycling technology is important. In this work, it was studied that the activated carbons were prepared from polyester sliver and that those were utilized as an adsorbent for environmental purification. The activated carbons prepared from polyester sliver, whose properties and adsorption performances were equal or superior to ordinary activated carbons on the market, were obtained by the control of activation conditions. Activated carbon with more than 1500 m 2 /g of specific surface area was obtained in the case of steam activation. However the specific surface area of the activated carbons by CO2-activation was smaller than those by steam activation. It was possible that the pore size of the activated carbons by CO2-activation was larger relatively from results of porosities analyzed. Adsorption isotherms of 4-nonylphenol 4NP in water, which was recognized as one of endocrine-disrupting chemicals, were measured by using the activated carbons prepared from polyester sliver. It was found out that the activated carbons were available effectively for adsorptive removal of 4NP in environmental water and that adsorption performance for 4NP could be improved by controlling the conditions for preparation of the activated carbon.