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Double refractory gold ores (DRGOs), in which few percentages of carbonaceous matter are present and gold grains are encapsulated in sulfides, have been abandoned to develop due to economic loss caused by adsorption of Au(CN)2− on carbonaceous matter after cyanidation in spite of the relatively higher Au contents than in usual gold ores. To avoid using extremely toxic reagent like cyanide, alternative ligand was examined to extract Au and the affinity between Au complex and carbonaceous matter was concerned in the present work. Two double refractory gold ores with different graphitic degrees were selected to pretreat for sulfide and carbonaceous matter decomposition, and then thiourea and cyanide extraction were performed to compare the leaching characteristics. Bio-oxidation with iron-oxidizing bacteria and chemical oxidation with FeCl3 were used as pretreatment for sulfide degradation, followed by carbonaceous degradation with laccase. For DRGO with a high graphiticity carbonaceous matter and complete removal of sulfides by pretreatment, the extraction rate was over 80% for both cyanidation and thiourea leaching. Meanwhile, for a lower graphiticity carbonaceous matter-bearing gold ores, cyanidation showed a decrease in gold extraction rate due to preg-robbing of Au(CN)2− complexes, however, thiourea extraction showed the stable extraction. Thiourea leaching was suitable and superior in gold extraction from low graphitc degree carbonaceous matter-bearing gold ores after sulfide decomposition.

Removal of borate in mine drainages by co-precipitation with hydroxyapatite (HAp) was developed from a laboratory scale to a pilot scale. Weakly acidic initial pH facilitated to enhance dissolution of Ca(OH)2 and decrease the dissolved carbonate concentration, leading to efficient immobilization of borate and arsenate. The NH4H2PO4 lowered best the equilibrium B concentration among different phosphate sources, avoiding the lattice strain of HAp. The added molar ratio of P/Ca significantly influenced the decreasing behavior of the B concentration, showing the optimal value of 0.3. In case of P/Ca larger than 0.30, the excess concentration of PO43- was probably adsorbed on Ca(OH)2 particles to prevent the dissolution, resulting in inhibiting the formation of HAp. In case of P/Ca smaller than 0.30, the production of HAp was limited, leading to less immobilized borate. All the optimized conditions as above were applied to the pilot scale with a 250 L reactor, where borate concentration was effectively reduced in also both batch and continuous tests.

An Advanced Graduate Program in Global Strategy for Green Asia (GA) is a component project of the "Program for Leading Graduate Schools" which is supported by the Japan Society for the Promotion of Science (JSPS) and started in 2013. The concept of a “Green Asia” is a bold ideal. Some of the most challenging global environmental conditions now exist in Asia. Many developing countries face the difficult task of raising millions of citizens from poverty. Consequently, environmental concerns are often overlooked. The key to this complex issue is scientific innovation and a transfer of knowledge from technologically advanced to less advanced nations. This educational program aims to cultivate leaders in science and technology who are able to contribute to the realization of an Asia where ecology and economic growth can coexist. Only 20 exceptional students including 10 Japanese and 10 international are allowed to enroll in the GA program each year. This elite group are taught in a bespoke educational environment, also benefitting from the vast collective resources and shared facilities of KU. The students are offered a financial support in order attract the premium candidates and to maximize the available study time by avoiding the need for part time jobs. The students of the Green Asia Education Program follow a stage gate system. This system comprises of six stages, Research Laboratory Rotation, Practice School, Coursework, International Seminar, Internship and the Green Asia Seminar. All activities described above are carried out in English in order to educate international and multicultural sense. Through these program, the students acquire five abilities, which are research, global perspective, leadership, practice and system landscape. In addition, applied skills such as expansion, analysis and upstream thinking skill are also trained by various activities, especially, practice school and international internship. As first batch students had finished this program in March 2017, we introduce the GA program and how the program is managed and carried out in order to make this program better.

Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident produced much amount of radioactively contaminated water at the Great East Japan Earthquake. 137Cs and 90Sr have been focused to remove from the contaminated water using zeolite types of adsorbents. Other radionuclides have been treated and removed separately by Advanced Liquid Processing System (ALPS), where resin is used to immobilize anions. However, these kinds of spent-adsorbents are not suitable for long-terms burying because of its instability, and the representative anionic radionuclides (129I, 36Cl, 99mTc and 79Se) have quite long half-life (105-107 years). Montmorillonite (Mt) is an useful adsorbent because of its high chemical stability and large cationic exchange capacity. In the present work, surfactant modified Mt (OMt) has been developed using hexadecylpyridium chloride for adsorption of ClO4-, which is a surrogate of 99mTcO4-. For stabilization of spent-OMt, cement solidification was examined with varying the ratio of spent-OMt content. To evaluate its chemical and physical stability, soaking and compressive strength tests were conducted. As a result, it was revealed by FTIR and 29Si-NMR that with increase in OMt contents, the linkage of calcium silicate hydrate was more developed.

Recycling high-purity rare earths from the waste in fluorescent lamps will assist in preserving rare earth resources. However, the present recovery from the waste in fluorescent lamps is very low at around 30%, and most waste fluorescent lamps are reclaimed. In this study we attempted to reduce one cause of difficulty in recycling lamps, namely the identification of rare earths in plastic-covered lamps, which is conventionally executed by human operators. Using the Acoustic Emission (AE) signal of the collision sound between lamps and an AE sensor head, we first carried out waveform analysis, and frequency analysis using the discrete Fourier transform. We extracted six feature values for each analysis and differentiated the plastic-covered lamps using thresholds. The least error rates were 4.85% and 6.67% for the waveform and frequency analyses, respectively. Second, we applied discriminant analysis on the six feature values from each analysis, resulting in error rates of 3.03% and 5.45%, respectively. Third, we extracted six feature values from the time-frequency analysis using the discrete Wavelet transform and Fractal dimensioning, and applied discriminant analysis on the six feature values, resulting in an error rate of 4.24%. Finally, we examined all the results from the three analyses to find the best combination of feature values, applied discriminant analysis to 12 feature values from the time analysis and time-frequency analysis, and succeeded in reducing the error rate to 0%.