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This study approach is to establish the healthy water environment and inhibiting the water disease. Recently, various type of pathogenic microorganisms has been reported in worldwide. In the future, to prevent the water disease from pathogenic microorganisms and to treat properly them has been required. The disinfection is important as in order to prevent the water diseases. This study aim is to evaluate the inactivation of pathogenic microorganism with combined chlorination and UV disinfection techniques. In the combined method, chlorination was performed after irradiated UV and the indicator of pathogenic microorganism was used coliphage MS2. Phosphate buffer solution was as the sample and the combined chlorine which was generated by reacted to ammonium chloride and Sodium hypochlorite to the sample. As the experimental results, the Synergistic effect was confirmed to perform by combined chlorination and UV disinfection. The inactivation effect was promoted by conducting combined to UV compared with chlorination alone. By performing the chlorination after irradiation UV as 60 mJ/cm2, the inactivation rate was increased about 1.5 times.

The appearance and spreading of the drug-resistance microorganisms are considered problematic in worldwide. The drug-resistance microorganisms are existed not only in medical institution but also in sewage and in environmental water. Measures against them are urgently required. This study was focused on chlorination and UV irradiation as disinfection technology for the drug-resistance E.coli which might be detected in the sewage and to evaluate the inactivation performance. In chlorination treatment, when the 6 drugs-resistance E.coli and non-resistance E.coli were compared, non-resistance E.coli could be expected to be inactivating more than 5 Log at 0.1mg/min・L with CT value. Meanwhile, the 6 drugs-resistance E.coli had the chlorine resistance higher than non-resistance E.coli and could be inactivating 4 Loa at 0.4mg/min・L with CT value. In UV irradiation treatment, the inactivation rate was proportional to UV dose and was same respectively. However, at the initial stage of UV irradiation, about 0 to 2 mJ/cm2, the 6-drugs resistance E.coli had UV resistance and UV dose required for 90% inactivation was about 13.4 mJ/cm2. Meanwhile, UV dose required for 90% inactivation of the non-resistance E.coli was about 6.6mJ/cm2.

Niobium penta-butoxide (Nb(OBu^n)_5) was synthesized from NbCl_5 in a plant scaleoperation. The content of Ta (OBu^n)_5 in Nb (OBu^n)_5 was decreased by the distillation of Nb (OBu^n)_5 using thin film down flow type molecular distillator. But the distillation method was not effective for obtaining the 4N purity Nb (OBu^n)_5 because the Nb (OBu^n)_5 was thermally unstable. Ultra fine Nb_2O_5 powder was produced by the hydrolysis of Nb (OBu^n)_5. Some physical properties of the Nb_2O_5 fine particle, such as specific surface area, mean particle size, apparant density condensation, were measured. The purity of the obtained Nb (OBu^n)_5 and the yield of niobium in the plant operation were 99.996% and 82.3%, respectively.

An industrial plant for the recycling of the Ni-Ti alloy scrap was proposed and constructed. The proposed plant which produces high purity UFP (Nb)_2O_5 consists of chlorination, distillation, hydrogen reduction, alkoxidation and hydrolysis processes. A Nb(Cl)_5-Ti(Cl)_4 mixture was obtained by the operation of chlorination plant of Nb-Ti alloy at 300℃. The content of Ti(Cl)_4 in the Nb(Cl)_5 was decreased less than 15ppm by the distillations of Nb(Cl)_5-Ti(Cl)_4 at 136 and 204℃. The hydrogen reduction process in which (Nb)_3(Cl)_8 was formed from Nb(Cl)_5 was effective for the production of 4N grade Nb(Cl)_5 containing trace amount of tantalum.

Zircomum is one of the important rare metals for advanced technology. The caldasite, a mixture of zircon and baddeleyite, from Brazil, can be an additional source of zirconium if it is suitably processed. High temperature chlorination of such an ore has many advamages in process development. In this paper, studies have been made to extract zirconium from caldasite through a chloride process. This process consists of chlormation of the ore and the selective condensation of volatile chlorides containing zirconium. The salient features of the chlormation studies are given below. 1) Caldasite ore reacts with Cl_2 gas at about 1000K producing metal chlorides enriched ZrCl_4. 2) 96% of the ore can be chlorinated with a recovery of 95% of zirconium. 3) By selective condensation of the mixture of volatile chlorides consisting of ZrCl_4-FeCl_3-AlCl_3,it has been possible to obtain ZrCl_4 of 97 mole% purity. 4) The same principle has been applied to the chlorinated products of caldasite to obatain zirconium chloride. 5) A process flowsheet for chlorination of caldasite to extract zirconium has been proposed.

Since rare metals have many advantages in high advanced technology fields, a stable supply of these metals is very important in a highly industrialized country like Japan. Developing an urban mine in which these metals are condensed is a possible solution to this problem. In this report, we discuss the recycling of tantalum from capacitor scrap via a chloride process. The results are as follows : 1) Capacitor scraps reacted with Cl_2 gas at about 623K producing TaCl_5,while Ta_2O_5 and MnO_2 did not react with Cl_2 and remained as residues. 2) Mn content in recovered TaCl_5 was decreased to 0.007%, but that in the residue was enriched to 13.2%. 3) In the case of capacitor chlorination, a low reaction rate of 55% was obtained. Some pretreatment like crushing must be considered. 4) Chlorination of ground capacitor scrap powder after reductive leaching gave a high reaction rate of 95% and a low Mn content in TaCl_5 of less than 1ppm. 5) The probable process for recycling of Ta capacitor scrap corresponding to advanced material production was proposed based on the above results.

The zirconium deposit of the Pocos de Caldas Plateau is north of São Paulo, Brasil, on the boundary between the States of Minas Gerais and São Paulo. The zirconium ore was formed as a mixture of baddeleyite (ZrO_2) and zircon (ZrSiO_4) which was identified as caldasite from the microscopic, X-ray and electron microprobe studies. This ore also contained a high content of uranium and thorium oxides, enough for nuclear fuel resources from the γ-ray spectrometry. The ore shows stable behavior in the TG-DTA studies but the metamictization by the α radiation damage from uranium and thorium seems to have occurred. The possible production process of zirconium from the caldasite was discussed mainly in the distillation process. Finally the evaluation of the caldasite as a zirconium resource was conducted from the metallurgical point of view.