Various zeolites were synthesized though hydrothermal treatment of perlite with alkaline solutions in order to facilitate effective use of the discarded perlite. Perlite is volcanic glass mainly composed of amorphous aluminum silicate and its composition is a main component SiO2 and Al2O3 with less impurities such as heavy metals. Therefore, zeolite synthesis from perlite is more convenient compared to from other waste materials (slag, ash, etc.). The obtained zeolites were analyzed by X-ray diffraction and SEM. As the result, FAU, PHI, SOD and CAN zeolites were able to be generated from perlite by changing the hydrothermal treatment condition.
Extraction behavior of cobalt from sulfate media containing excess manganese by mixtures LIX63 and several amines was investigated. The addition of amines shifted cobalt extraction isotherm to higher pH region in all case. The degree of the pH isotherm shifts depended on the basicity of each amine in the case of manganese however did not depend on it in the case of cobalt. The separation ability of cobalt from manganese was highest in case of LIX63 and primary amine system.
Recently the treatment of mine drainage, especially acid mine drainage (AMD) is attracting a lot of attention, including the passive treatment that is a cost-effective and energy efficient process. In such a process, the natural geochemical reaction, gravitational flow, bacteria metabolism, etc, are utilized for the active treatment, enabling continuous addition of chemical reagents and maintenance of mechanical facilities, and so on. For a long time, the development of the passive treatment was mainly carried out in North America and Europa, thus, much useful knowledge is cultivated and many experimental and actual sites are operated in these area. In this paper, the useful knowledge, information and instances related to the passive treatment are reviewed. The performance of sulfate reducing bacteria (SRB) is very important for the treatment of the mine drainage from non-ferrous mine sites. Thus, the matters related with SRB, that is, the reaction, the reactor and the operation are also described in detail.
Mineral prices hit their ceilings and started fluctuating. It forced resource-related companies to reassess their assets. In order to secure the stable supply of resources, it is important for Japan, which is a resource-importing country, to keep an eye on the changes in strategies of resource-related companies, especially mining giants that dominate the global production of various minerals. There are some studies focusing only on risk management at an individual mine level and fluctuation in mineral prices, but few studies focus on asset management of the mining giants as an entity. The purpose of this paper is to analyze and understand the asset management strategies of the mining giants. All assets of the giants, such as mines, smelters and refineries are considered as risky assets, calculating the optimal portfolio under the “Modern Portfolio Theory”. By comparing the derived optimal portfolio with the actual one, we conclude that the mining giants' asset management strategies are almost optimal. We also found out which asset will be on sale from each company, which can be useful for Japanese companies increasing the share in overseas mines.