• 한국응용과학기술학회지
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• 제33권2호
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• pp.401-410
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• 2016

금속 산화물과 혼합한 $Pt-Sn/Al_2O_3$ 촉매의 프로판 탈수소 반응 성능의 향상 가능성에 대해서 연구하였다. 금속 산화물로서 $Cu-Mn/{\gamma}-Al_2O_3$, $Ni-Mn/{\gamma}-Al_2O_3$, $Cu/{\alpha}-Al_2O_3$를 제조하여 $Pt-Sn/Al_2O_3$ 촉매와 혼합하고, 프로판 탈수소 반응 성능을 측정하였다. 이 결과들을 불활성 물질인 glass bead를 혼합한 $Pt-Sn/Al_2O_3$ 촉매를 기준샘플로 삼아 비교하였다. 촉매와 금속산화물을 환원처리하지 않고 반응 실험한 경우, $576.5^{\circ}C$에서 기준샘플의 전환율 8% 대비, $Cu-Mn/{\gamma}-Al_2O_3$를 혼합한 $Pt-Sn/Al_2O_3$ 촉매가 14.9%의 높은 전환율과 96.8%의 선택도를 보였다. 촉매와 금속산화물을 환원 처리하여 반응활성을 측정한 경우, $Cu/{\alpha}-Al_2O_3$과 $Pt-Sn/Al_2O_3$의 혼합촉매가 기준샘플대비 초기에 높은 수율을 보였다. 그러나, 촉매를 환원 처리한 경우 전반적으로 전환율 상승이 크지 않았고, 이것으로 $Cu-Mn/{\gamma}-Al_2O_3$의 격자산소가 탈수소반응의 전환율 증가 영향을 주었음을 알 수 있었다.

• 한국막학회:학술대회논문집
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• 한국막학회 1994년도 추계 총회 및 학술발표회
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• pp.8-11
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• 1994

Disposal of hazardous ions in the aqueous streams is a significant industrial waste problem.. Waste streams from electronics, electroplating, and photographic industries contain metal ions such as copper, nickel, zinc, chromium(IV), cadmium, aluminum, silver, and gold, amongst others in various aqueous solutions such as sulfates, chlorides, fluorocarbons, and cyanides. Typical plating solutions having similar compositions are listed in Table 1. Spent process streams in catalyst manufacturing facilities also contain precious metals such as Ag, Pt, and Pd. Developing an effective recovery process of these metal ions for reuse is important.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 가을 학술발표회 논문집
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• pp.219-222
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• 2001

Membranes which selectively transport specific metals on an industrial scale is much useful in a number of applications, such as aqueous stream purification, catalyst and recycling of the reactants, the applications in metal ion sensing and so forth. Numerous studies have been already made to use liquid, supported liquid and, emulsion liquid membranes (LM) for selective carriers for metal ion transport. (omitted)

• Carbon letters
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• 제3권3호
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• pp.146-151
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• 2002

Activated carbon fibers were prepared from the petroleum isotropic pitch and organometallic compounds. The metalsvwere dispersed uniformly in the ACFs. The specific surface area and pore size distributions of metal containing ACFsvwere measured. The mesopores of ACFs were developed by Co, Ni, and Mn metals addition and the catalytic reactivityvof ACFs'SOx removal was increased by adding Ni and Pd metals. It was found that the mesopores did not work forvthe improvement of catalytic reactivity of ACFs' SOx removal with the blank experiment using the metal removedvACFs.

• 한국수소및신에너지학회논문집
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• 제26권6호
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• pp.507-515
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• 2015

HI decomposition reaction requires a catalyst for the efficient production of hydrogen as a key reaction for hydrogen production in sulfur-iodine thermochemical water-splitting (SI) cycle. As a catalyst used in the reaction, the performance of platinum catalyst is excellent. While, the platinum catalyst is not economical. Therefore, studies of a nickel catalyst that could replace platinum have been carried out. In this study, the characteristics of the catalytic HI decomposition on the amount of loaded nickel (Ni = 0.1, 0.5, 1, 3, 5, 10 wt%) were investigated. As the supported Ni amount increased up to 3 wt%, HI decomposition was found to increase in linear proportion. However, the conversion of $Ni/Al_2O_3$ catalyst loaded above 3 wt% was not linear. It was thought that the different HI decomposition characteristics was caused in the size and metal dispersion of Ni particles of catalyst. The physical property of catalyst before and after HI decomposition reaction was characterized by BET, chemisorption, XRD and SEM analysis.

• 한국수소및신에너지학회논문집
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• 제17권3호
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• pp.248-254
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• 2006

The promotion effects of noble metals upon the activity and reducibility in steam methane reforming over $Ni/MgAl_2O_4$ catalysts were investigated. While $Ni/MgAl_2O_4$ catalysts require the pre-reduction by $H_2$, the noble metal-added catalysts show high catalytic activities without pre-treatment. According to $CH_4$-TPR, the addition of noble metal makes the $Ni/MgAl_2O_4$ catalyst easily reducible. The reduction degree of NiO in the noble metal-added catalysts after using at $650^{\circ}C$ without pre-reduction was $15{\sim}20%$, and was lower than that in the $H_2$-reduced $Ni/MgAl_2O_4$ catalyst(reduction degree=27%). The enhancement of the catalytic activity over noble metal-added catalysts results from easier reducibility by addition of noble metal and the synergy effect between noble metal and Ni.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.217-217
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• 2011

Recently, demand for thermally stable metal nanoparticles suitable for chemical reactions at high temperatures has increased to the point to require a solution to nanoparticle coalescence. Thermal stability of metal nanoparticles can be achieved by adopting core-shell models and encapsulating supported metal nanoparticles with mesoporous oxides [1,2]. However, to understand the role of metal-support interactions on catalytic activity and for surface analysis of complex structures, we developed a novel catalyst design by coating an ultra-thin layer of titania on Pt supported silica ($SiO_2/Pt@TiO_2$). This structure provides higher metal dispersion (~52% Pt/silica), high thermal stability (~600$^{\circ}C$) and maximization of the interaction between Pt and titania. The high thermal stability of $SiO_2/Pt@TiO_2$ enabled the investigation of CO oxidation studies at high temperatures, including ignition behavior, which is otherwise not possible on bare Pt nanoparticles due to sintering [3]. It was found that this hybrid catalyst exhibited a lower activation energy for CO oxidation because of the metal-support interaction. The concept of an ultra-thin active metal oxide coating on supported nanoparticles opens-up new avenues for synthesis of various hybrid nanocatalysts with combinations of different metals and oxides to investigate important model reactions at high-temperatures and in industrial reactions.

• 한국재료학회지
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• 제32권2호
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• pp.98-106
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• 2022

Metal-organic frameworks (MOFs) are widely used in various fields because they make it easy to control porous structures according to combinations of metal ions and organic linkers. In addition, ZIF (zeolitic imidazolate framework), a type of MOF, is made up of transition metal ions such as Co²⁺ or Zn²⁺ and linkers such as imidazole or imidazole derivatives. ZIF-67, composed of Co²⁺ and 2-methyl imidazole, exhibits both chemical stability and catalytic activity. Recently, due to increasing need for energy technology and carbon-neutral policies, catalysis applications have attracted tremendous research attention. Moreover, demand is increasing for material development in the electrocatalytic water splitting and metal-air battery fields; there is also a need for bifunctional catalysts capable of both oxidation/reduction reactions. This review summarizes recent progress of bifunctional catalysts for electrocatalytic water splitting and metal-air batteries using ZIF-67. In particular, the field is classified into areas of thermal decomposition, introduction of heterogeneous elements, and complex formation with carbon-based materials or polyacrylonitrile. This review also focuses on synthetic methods and performance evaluation.

• 한국수소및신에너지학회논문집
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• 제34권6호
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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.

• 대한방사성의약품학회지
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• 제3권2호
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• pp.116-121
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• 2017

To overcome the low reactivity and solubility of alkali metal fluorides (MFs), various types of phase transfer catalysts (PTCs) have been developed over the last decades. However, since the fluoride activated by such PTC sometimes has a strong basicity, it may cause various side reactions such as elimination reaction or hydroxylation reaction in the nucleophilic fluorination reaction. Also, they may cause separation problems in the compound purification process. In recent advanced study, various PTCs have been developed to solve these problem of conventional catalyst. In this review, we would like to introduce three kinds of novel multifunctional organic catalysts such as bis-tert-alcohol-functionalized crown-6-calix[4]arene (BACCA), easy separable pyrene-tagged ionic liquid (PIL) by reduced graphene oxide (rGO), and tri-tert-butanolamine organic catalyst.