Recently, SX - EW process for copper oxide is getting very popular. This process, however, is not applicable for chalcopyrite. Therefore, the development of new hydrometallurgical processes in which chalcopyrite is efficiently refined is essential. In these processes, the Cuprex process and the Intec process are introduced for the chloride solution process, and then, the CESL copper process and the total pressure oxidation process are also introduced for the pressure leaching process in sulfuric acid solution. The cuprex process has the solvent extraction process using Acolga reagents, and the Intec process has the electrowinning process using BrCl^- ₂(Halex). In the CESL process almost all of sulfur is recovered as an elemental sulfur through pressure leaching process. On the other hand, in the total pressure oxidation sulfur is almost completely to be oxidized to sulfate ion. Generally, hydrometallurgical processes have several advantageous points; 1) SOx is not exhausted, 2) capital cost and running cost are cheaper, 3) grade of concentrate and impurities do not affect the operation so much, 4) facilities are more compact, and so on.

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Freezing and thawing action as one of the important external factors of rock slope failures is emphasized in cold regions. Investigations were made on the crack development in saturated welded tuff specimen by freezing and thawing action in this study. The freezing test was conducted in a temperature-controlled chamber in the laboratory where temperature varied from +5 °C to-18 °C. The freezed rock specimens were thawed in distilled water. The test lasted 3.5 hours for each freezeing and thawing cycle including 2 hr for freezing and 1.5 hr for thawing. P-wave velocity and acoustic emission of specimens were measured during freezing. The investigation on change of appearance on outer surface and section of the specimen as well as pore water migration and crack development were done.
The initial cracks in rock specimen by freezing-thawing action started from the weak of surface layer such as pumice, mudstone and the interface of gravel and volcanic glass, then propagated to inside of the specimen. The cause is that the degree of saturation in surface layer is higher than that of inside due to pore water migration during freezing. The patterns of cracks by freezing and thawing is affected by the rock structure and pore water migration.

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Artificial rocks have been often used in aquariums, zoos, botanical gardens and parks etc. However, recently, opportunity to use the artificial rocks on surfaces of various structures is increasing. This probably comes from the reason that using the artificial rocks is effective from a view point of balancing with environment, so demand of them is expected to increase in near future. To meet the demand, it is desired to clarify strength, deformability and thermal properties of artificial rocks. In this study, these properties for two types of artificial rocks at high and low temperatures and effects if thermal hysteresis on them were examined. The results indicated that the artificial rocks are able to be used on the surfaces on structures exposed to temperature change in wide variety of natural environment.

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Kaolinite was treated with urea to form urea - kaolinite complex, then delaminated by grinding using a mechanical mortar. The delaminated products and their deintercalated products were characterized by specific surface area measurement, X - ray diffraction and infrared absorption analysis. The results are summarized below.
The specific surface area of the kaolinite treated with urea remarkably increased by grinding for more than 3 h. The basal spacing of the treated kaolinite increased due to the intercalation of urea into the kaolinite structure, and the decrease in attractive force acting between silicate layers of kaolinite. It caused that kaolinite was easily delaminated by grinding. The basal spacing of urea - kaolinite complex was decreased from 10.8 Å to 8.3 Å by boiling and washing. The 8.3 Å basal spacing is larger than the kaolinite (7.2 Å). This result indicates that a molecule decomposed from urea (NHCO) still remains in the kaolinite structure.

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To produce an artificial aggregate of stable quality, investigations of the expansion / sinter mechanism of coal fly ash are required. The purpose of this study is to clarify the influence of carbonecious substances on pellet expansion by firing, especially related to the atmospheric conditions.
The study revealed two types of expansion. One relates to unburned coal fragments which exist separately from ash particles. In this case, large pores are formed around an oxidization front in the expanded pellet, accompanied by a macroscopic double - core structure in the sintered zone proceeding from outside. The other relates to very small coal fragment trapped in glassy spheres. Because the spheres in the pellet are distributed homogeneously, small pores are also inflated homogeneously with producing CO₂ and CO. These gasses are generated by a reaction of the unburned coal fragments and oxygen in the glassy structure.

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The production of synthesized zeolite from paper sludge ash by alkali hydrothermal reaction was investigated and the physical properties of the products were measured in this study. In the combustion process of paper sludge, usually either calcium carbonate or calcium hydroxide is used as a neutralization agent. After burning, calcium oxide and unreacted calcium carbonate are remained in paper sludge ash. The effect of the calcium oxide and calcium carbonate was studied on the crystallization of zeolite and filtration characteristics of the slurry obtained from the hydrothermal reaction. In order to confirm the possibility to use zeolite as a water purification agent, the adsorption test of ammonium ion in the aqueous solution was carried out.
The zeolite synthesized in this study from paper sludge ash has a sufficient cation exchange capacity, which makes a practical use possible. It was also found that calcium oxide and unreacted calcium carbonate in the ash cause the depression of filtration rate of the slurry and sedimentation rate through the reaction with sodium hydroxide. It was clarified that sodium ion in the synthesized zeolite can exchange with ammonium ion in the aqueous solution.

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Silver activity in the immiscible region between the molten copper and Cu - Fe matte of the Cu - Fe - S system was measured by applying a double Knudsen cell - mass spectrometric method at 1,473 K for analyzing the behavior of minor elements in a copper smelting process. The silver distribution between the two phases in the miscibility gap was also determined to find the relationship of the silver activity and composition in both the matte and copper phases with a quenching technique at the same experimental temperature. The following results have been obtained in the present study.
The distribution coefficient of silver between the matte and copper phases, which is defined by {% Ag in matte} / [%Ag in metal] decreases from 0.4 at the iron free Cu - Cu₂S immiscible region to 0.29 at the composition of iron saturation with increasing iron content.
The activity coefficient of silver at infinite dilution in the matte, γ^o_Ag' changes from 9.9 in the Cu₂S phase to 16 at γ - iron saturation in the Cu - Fe matte by addition of iron while the value of 3.3 for γ^o_Ag in the metal phase equilibrated with the matte phase is kept at almost constant. The value of 0.22 is obtained for ε^Fe_Ag in molten copper by using the activity values in the copper phase combined with the reported values of ε^S_Ag in molten copper and γ^o_Ag in the Cu - Ag binary system. It is understood by the value of ε^Fe_Ag obtained in the present study that the quite small change of γ^o_Ag is observed with increasing iron content in the copper phase of the Cu - Fe - S system.
γ^o_AgS0.5 in the matte phase is estimated from the distribution ratio of silver between the two phases combined with γ^o_Ag in the metal phase and ρ_S2 over the two phase region by assuming the formation of AgS_0.5 in the matte phase. The obtained value for γ^o_AgS0.5 changes from 0.81 in the iron free matte into 0.96 in the iron saturated matte, which exhibits nearly ideal behavior.

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The extraction of divalent zinc and cadmium from aqueous solutions containing hydrochloric acid and / or lithium chloride has been carried out by using dihexyl sulphoxide (DHSO, R₂SO) in benzene. The organic extracts were examined by Raman and nuclear magnetic resonance spectroscopies. As the results, it was found that the distribution coefficients rise with increasing the chloride ion concentration of aqueous solutions; the extraction efficiency of DHSO for zinc (II) is higher than that for cadmium(II) at [HCl] _{init aq} ≤ 4mol dm^-3, while its order becomes contrary above that acidity. The extraction of zinc(II) and cadmium (II) from hydrochloric acid solutions by DHSO is expressed by the following equilibrium equations: MCl₂ (aq) + 2R₂SO (org) ⇔ MCl₂·2R₂SO (org), MCl^-₃(aq) + H⁺ (aq) + 3R₂SO (org)⇔HMCl₃·3R₂SO (org) and MCl^2-₄(aq) + 2H⁺ (aq) + 2R₂SO (org)⇔H₂MCl₄·2R ₂SO (org), where M = Zn or Cd.

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Environmental problems have recently attracted attention in the world, and there has been an increased demand for the recycling of used materials and products. The dry battery is mainly composed of zinc and manganese, and as Japan is completely without self - sufficiency in manganese, it is desirable that the manganese in used dry batteries can be reused.
Manganese in the used dry battery mainly exists as manganese dioxide, which is insoluble. It is known that manganese ore can be leached in sulfuric acid solution with sucrose. Therefore, in this work, as a basis for developing a method of recycling used dry batteries, the process of leaching it in sulfuric acid solution with sucrose was investigated.
Zinc in used dry batteries was able to be completely leached, while about thirty percent of manganese was able to be leached in the absence of sucrose. However, with the addition of sucrose the rate of leaching of manganese more than twice. This was the reason why manganese dioxide which was insoluble was reduced by sucrose and leached. To change a pulp density from 30 to 150 g / l, a decrease in leaching percentage of manganese was under ten percent. Used dry batteries were easily leached in the sulfuric acid solution with sucrose, so it was possible to apply this leaching process to recycling of dry batteties.
Glucose and fructose, which were formed by the hydrolysis of sucrose, were reactants in the case of leaching manganese dioxide in sulfuric acid solution with sucrose. Each of them was able to leach manganese dioxide. Temperature dependency of the leaching of manganese dioxide in the presence of sucrose, glucose or fructose was studied and as each activation energies of these reactions were found to be, 87.9, 76.6 and 74.9 kJ / mol, respectively.

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The study on synthesis process and structure of silica-gel particles modified Al / Mg has been achieved. The modified silica gel has been expected for functional materials and catalysts. An atomizer is used for particle production of silica gel. But, many hollow particles which were easily destroyed by handling were produced in the atomizer process. The number of those weak particles decreased with increasing the viscosity of silica - sol which could be controlled by treated in relatively unstable state such as pH = 2 and 40°C , 50h. Small silica particles in silica sol was thought to bind each other during the treatment and form apparently larger molecular weight silica - sol chain. In subsequently drying process, Al and Mg nitrates which had been mixed with silica sol changed partly to the oxides such as MgAl₂O ₄ and MgO and partly to the elements which constructed the modified silica - gel. The chemical and physical structure of the calcinated modified silica gel were stable in the region from 450 °C to 700 °C. Half of Al and quarter of Mg were in modified silica gel structure, where (Si -O)_n ^- Al·Mg²⁺, MgAl₂O ₄, and MgO were observed by thermal analyses (TG, DTA) and NMR. The chemical structure as well as physical structure was unstable at more than 700 °C. Pore volume rapidly decreased and the coordination number of Al fluctuated between four to six from 700 °C to 1,000 °C. The synthesis process and the structure of Al / Mg modified silica gel were partly clarified.

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