• Clean Technology
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• v.17 no.3
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• pp.225-230
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• 2011

Characteristics of hydrocarbon selective catalytic reduction of NOx using various noble metal catalysts were investigated. The best active metal is Pt, supports are $CeO_2$ and $TiO_2$ by strong interactions between active metals, and 55% of conversion rate of NOx is shown. Pd, Rh and Ag catalysts presented a conversion of less than 20% as active metals, and supports also showed the poor activity compared to $SiO_2$ and $ZrO_2$. Experiments were performed with different types of reducing agents, amount, concentration of oxygen and space velocity in order to investigate the performance of catalysts according to operating conditions. The results confirm that the methane is better than propane as a reducing agent, and as the ratio of methane/nitrogen oxide increases, the catalytic activity increased, as the concentration of oxygen increases and space velocity decreases, the performance of catalysts increased.

• Analytical Science and Technology
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• v.13 no.3
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• pp.309-314
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• 2000

The quantitative analysis of various trace metals including fission products in lithium molten salts has been performed using a inductively coupled plasma atomic emission spectrometer (ICP-AES). The spectral interferences of lithium content, 500, 1,000 and 2,000 mg/L, in the sample solution were investigated using an optimum wavelength for the respective metal species. As a result, the line intensities for Y, Nd, Sr, and La had no influences from the lithium content up to 2,000 mg/L, while Mo, Ba, Ru, Pd, Rh, Zr and Ce showed spectral interferences of 10% to 50%. The group separation of metals from lithium in the molten salts solution was carried out by adding ammonia water into the solution. The recovery of Ru, Y, Rh, Zr, Nd, Ce, La and Eu was found to be over 90%, while Mo, Ba, Pd, and Sr provided low recovery percentages.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.6
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• pp.587-593
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• 2023

This research project focused on the production of hydrogen through ammonia decomposition reactions while investigating how the reactivity of this process varies when employing different catalysts. Several metal oxide supports (Al₂O₃, La₂O₃, CeO₂) were utilized as catalysts, with active metals from both the transition metal group (Co, Ni, Fe, Cr, Cu) and the noble metal group (Ru, Rh, Pd, Pt) impregnated onto these supports. Furthermore, the study examined how the reactivity evolves with changes in reaction temperature when employing the prepared catalysts. Additionally, the research delved into the distinctive activation energies associated with each of the catalysts. In this research, In the noble metal catalyst system, the order of high activity for ammonia decomposition reaction to produce hydrogen is Ru > Rh > Pt ≈ Pd. In the transition metal catalyst system, the order of high activity is Co > Ni > Fe > Cr > Cu.