• Resources Recycling
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• v.23 no.1
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• pp.3-16
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• 2014

Recycling of spent autocatalyst that includes the platinum group metals (PGMs), namely palladium, platinum and rhodium, is a very profitable endeavor. In order to ensure an efficient promotion of an appropriate policy-making and the technical development of the recycling process of spent autocatalyst in Korea, the generated amount, trading conditions, and recycling technology for spent autocatalyst were surveyed. The generated amount of spent autocatalyst was estimated by analyzing the domestic statistical data of registration & disuse of automobiles and the records of autocatalyst installation to new cars. The review of the recycling technology was carried out by surveying the recycling processes of 'Heesung PMTech Ltd.', which is the largest company in the recycling industry for spent autocatalyst in Korea. In addition to the above, some policy suggestions for the improvement of recycling industries for spent autocatalyst were offered.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.9
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• pp.1347-1353
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• 2006

Effects of microencapsulated chitooligosaccharide addition in milk were evaluated by determination of the efficiency of microencapsulation, cholesterol removal, color, viscosity and sensory properties. Coating material was polyglycerol monostearate (PGMS) and the efficiency of microencapsulation was 88.08% at a 10:1 ratio of coating to core materials (w/w). When 0.5% of microencapsulated chitooligosaccharide was added into milk, the color values (L, a, and b) and viscosity were significantly different from those of noncapsulated chitooligosaccharide-added groups (p<0.05). The release of chitooligosaccharide from microcapsules was 7.6% in milk at $4^{\circ}C$ for 15-day storage. In both 0.5 and 1.5% microencapsulation addition, the scores of all sensory characteristics except for off-flavor were significantly different between encapsulated chitooligosaccharide and noncapsulated chitooligosaccharide-added groups during all periods of storage. The present study indicated that chitooligosaccharide microcapsules could be applicable into commercial milk with little adverse effects on physical and sensory properties.

• Resources Recycling
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• v.20 no.4
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• pp.36-45
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• 2011

The recovery of platinum group metals (PGMs) from the leach solution of spent auto-catalyst and the wash solution of the leach residue was investigated in the laboratory scale experiments by the cementation process using metal powders as the reductant. In this study, the effect of Al, Mg and Zn powders on the cementation process was particularly examined. Aluminum powder was selected as the most suitable reductant for the cementation of PGMs. At the cementation time of 10 minute under the aluminium stoichimetric amount of 19.3 and the reaction temperature of $50{\sim}60^{\circ}C$, the recovery of platinum group metals from the leach solution of the spent auto-catalyst was found to be 99.3%, 99.4%, 90.2% for Pt, Pd and Rh, respectively. Under the same conditions with the aluminium stoichimetric amount of 45, the recovery of platinum group metals from the wash solution of the leach residue of spent catalyst was observed to be 97%, 97% and 90% for Pt, Pd and Rh, respectively. In addition, it was possible to upgrade the platinum group metals in the precipitates obtained from the cementation process by about 10% through the removal of metal impurities by the nitric acid leaching at ambient temperature.

• Resources Recycling
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• v.20 no.2
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• pp.74-81
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• 2011

The dry method and wet method are currently used for the recovery of platinum group metals (Pt, Rh, Pd) contained in spent automobile catalysts. The study herein aims to identify the melting condition and optimum collector metal in accordance with a comparison of each concentration change in melting waste catalysts, using Fe and Cu in a basic experiment to recover waste catalysts through application of the dry melting method. As a summarized result of the experiment herein, it was determined to be more advantageous to use Fe as a parent material rather than Cu from the aspect of recollection rate, and the concentration change rate of platinum group metals within slag was greatly enhanced at $1,600^{\circ}C$ melting condition rather than at $1,500^{\circ}C$ in terms of melting processing temperature. The mean concentration of platinum group metals - Rh, Pd and Pt - within slag after a melting process at $1,600^{\circ}C$ were 6.21 ppm, 5.98 ppm and 6.97 ppm. The Rh and Pd were 50.58% and 55.31% respectively greater than the concentration change rate of platinum group metals in slag at a melting temperature of $1,500^{\circ}C$. However, since the initial concentration of Pt within the waste catalysts was 12.9 ppm, is relatively low, it was difficult to compare concentration change rates after the melting process.

• Resources Recycling
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• v.21 no.6
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• pp.3-11
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• 2012

Some methods used for the recovery of osmium and ruthenium from primary/secondary sources are reviewed. Both Ru and Os could form volatile oxides which enable their separation from the other PGMs by distillation as a traditional method. In hydrochloric acid solution, they also form chloro-complexes with different valence states. Amines or amine based mixture have been used to extract Ru. Solvating extractants are employed to separate Ru and Os. The detailed extraction and stripping conditions of several solvent extraction processes have been reviewed. As an alternative to solvent extraction, solid-liquid method can be applied to recover trace amount of these metals.

• Journal of National Security and Military Science
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• s.7
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• pp.55-89
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• 2009

This article aims to critically review recent U. S. RMA-centered theories of warfare having prevailed after the 1991-92 Gulf War upon which the current ROKA military transformation project, the Vision 2020, largely based. In order to evaluate validity as a universal warfighing theory of NCW (Network Centric Warfare) and EBO (Effects-Based Operations), this article reviews the intrinsic strength and weakness of the theories as well as results of several recent wars that the U. S. Army conducted based on doctrines derived form such theories, In addition, this article examines the impact of certain military technology or weapon system in some well-known historical wars to draw lessons regarding the relationship between technology(weapon system) and military victory. Historical examples has shown that victories in war were not achieved by new technologies alone in most cases. Rather military victories tended to owe to combination of new technology, original doctrine and well conceived organization. Although the U. S. Armed Forces showed brilliant records of operational successes anchored on the system of PGMs and NCW concepts in Iraq (1991-92; 2003) and Afghanistan (2001-02), it must be pointed out that the operational successes did not bring about political ones in cases of Iraq and Afghanistan. It reminds us of perils of too technologically tilted approach to the conduct of war. In sum, one ought to recognize that superior technology nowadays became a necessary condition of success but is not yet a sufficient condition, the ROKA needs to be abreast with development trends of military technologies and related theoretical concepts, it need not too be in a hurry in adopting cutting edged war-making technologies at the expense of large amount of budget. The essay recommends for the ROKA several basic requirements for coping with conduct of future wars as well as establishing a 'Korean style military thought'; (1) Recognition of importance of technology in conduct of war; (2) Imposition of officer self-study hours in working days; (3) Establishing a lifestyle of military professionalism in the Korean officer corps; (4) Setting up small or large groups of think-tanks that are specialized in army doctrinal formulation.