• Proceedings of the Membrane Society of Korea Conference
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• 2005.11a
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• pp.196-199
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• 2005

원자력 고온가스의 열물 이용하여 수소를 생산을 하는 IS(Iodine-Sulfur)공정 중 HI분해-분리반응은 높은 열적-화학적 안정성이 요구되는 공정이다. 이러한 공정분위기에서 사용 될 분리막반응기의 촉매를 선정하고자 다양한 담체내에 백금(Platinum)의 함유량이 각각 다른 촉매를 사용하였다. HI 분해실험온도는 $300-500^{\circ}C$ 의 범위이며 일정량의 HI 용액을 기화시켜 촉매반응기에 정량적으로 공급하여, 가스크로마토그래피를 이용하여 분석하였다. 분해온도 변화와 다양한 담체내백금의 함유량 변화에 따른 HI전환율 확인하였으며, 반응 후 촉매에 대한 SEM과 XRD분석의 수행으로 촉매의 내구성과 변화를 확인하였다.

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.6
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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.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05b
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• pp.106-109
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• 2004

원자력의 고온가스로(HTGR)의 열원에서 약 1,00$0^{\circ}C$의 열을 이용하여 물을 분해하는 열화학적 수소제조 IS 프로세스는 다음과 같은 3단계 화학반응식에 의해 수소를 제조한다. 이들 화학반응의 수행과정을 반응온도와 공정에 따라 도식화하면 Fig. 1과 같은 3가지 공정으로 구성된다.(중략)

• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.633-638
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• 2008

The bunsen reaction, part of IS(Iodine-sulfur) cycle that one of the hydrogen production by the thermochemical water splitting, was investigated. It was observed that $H_2SO_4$ was uniformly generated and generation of $H_2SO_4$ was independent of iodine input. However, generation of HI was decreased with increasing iodine input. It was thought that HI and unreacted iodine were formed complex compound such as $HI_3$ $HI_5$ or $HI_7$. The complex compound accelerated liquid-liquid separation properties in the product. It was also revealed that reaction kinetics was increased with increasing iodine input. Liquid-liquid separation properties were improved with increasing iodine input and reaction temperature. Moreover, no side reaction was occurred at all reaction conditions.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.4
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• pp.415-423
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• 2011

HI decomposition step certainly demand catalytic reaction for efficient production of hydrogen in SI process. Platinum catalyst can apply to HI decomposition reaction as well as hydrogenation or dehydrogenation. Generally, noble metal is used as catalyst which is loaded form for getting high dispersion and wide active area. In this study, Pt was loaded onto zirconia, ceria, alumina, and silica by impregnation method. HI decomposition reaction was carried out under the condition of $450^{\circ}C$, 1atm, and $167.76h^{-1}$ (WHSV) in a fixed bed reactor for measuring catalytic activity. And property of a catalyst was observed by BET, TEM, XRD and chemisoption analysis. On the basis of experimental results, we discussed about conversion of HI according to physical properties of the loaded Pt catalyst onto each support.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.3
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• pp.219-226
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• 2014

In HI decomposition, $Pt/Al_2O_3$ has been studied by several researchers. However, after HI decomposition, it could be seen that metal dispersion of $Pt/Al_2O_3$ was greatly decreased. This reason was expected of platinum loss and sintering, which platinum was aggregated. Also, this decrease of metal dispersion caused catalytic deactivation. This study was conducted to find the condition to minimize platinum sintering and loss. In particular, heat treatment atmosphere and temperature were examined to improve the activity of HI decomposition reaction. First of all, although $Pt/Al_2O_3$ treated in hydrogen atmosphere had low platinum dispersion between 13 and 18%, it was shown to suitable platinum form that played an important role in improving HI decomposition reaction. Oxygen in the air atmosphere made $Pt/Al_2O_3$ have high platinum dispersion even 61.52% at $500^{\circ}C$. Therefore, in order to get high platinum dispersion and suitable platinum form in HI decomposition reaction, air heat treatment at $500^{\circ}C$ was needed to add before hydrogen heat treatment. In case of 5A3H, it had 51.13% platinum dispersion and improved HI decomposition reaction activity. Also, after HI decomposition reaction it had considerable platinum dispersion of 23.89%.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.637-641
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• 2007

화석연료의 고갈이 가시화됨에 따라 이를 해결하기 위한 대체에너지원의 확보를 위해 다양한 연구가 수행되어 왔다. 본 연구에서는 폐기물 특히 플라스틱 폐기물의 안정적인 처리 및 청정가스의 생산방법을 연구하기 위해서 선행적으로 플라스틱 폐기물의 열분해 특성을 조사하였으며, 그 반응모델을 제시하여 열분해로의 설계인자의 도출하고자 하였다. 대상 폐 플라스틱류로서 PE, PP, PVC, RPF 등을 이용하였고, 열중량분석기와 tube furnace를 통해서 온도에 따른 분해반응 특성을 확인하였다. 열분해 특성조사를 한 결과 PE, PP 등은 잔류 char가 없이 $400^{\circ}C$ 전후에서 완전 분해하였으며, PVC의 경우 $400^{\circ}C$ 이후에도 약 20% 이상의 char가 잔류함을 확인하였고, RPF의 경우에도 약 10%의 char이 잔류함을 확인하였다. 또한 각각의 열분해 특성을 DTG/TGA분석을 통해서 적정체류시간을 구할 수 있었고, 다단열분해 가스화기를 이용하여 합성가스를 제조한 결과 2500 kcal / $Nm^3$의 높은 발열량을 가진 합성가스를 제조할 수 있었다.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.3
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• pp.199-208
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• 2008

HI decomposition was conducted using Pt/C-based catalysts with a fixed-bed reactor in the range of 573 K to 773 K. To examine the change of the characteristic properties of the catalysts, $N_2$ adsorption analyser, a X-ray diffractometer(XRD), and a scanning electron microscopy(SEM) were used before and after the HI decomposition reaction. the effect of Pt loading on HI decomposition was investigated by $CO_2$-TPD. HI conversion of all catalysts increased as decomposition temperature increased. The XRD analysis showed that the sizes of platinum particle became larger and agglomerated into a lump during the reaction. From $CO_2$-TPD, it can be concluded that the cause for the increase in catalytic activity may be attributed to the basic sites of catalyst surface. The results of both b desorption and gasification reaction showed the restriction on the use of Pt/C-based catalyst.

• KSBB Journal
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• v.15 no.3
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• pp.238-242
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• 2000

A fusion protein of human interleukin-2(hiL-2) and glucagon which was expressed in Escherichia coli. was digested with enterokinase for recovery of hIL-2 from the fused protein. To obtain hIL-2 of optimum recovery hydrolysis reaction were performed under various conditions of urea additives and reaction time. hIL-2 was finally purified by RP-HPLC(reversed phase-HPLC) to remove cleaved G3 fusion partner and residual uncleaved G3-IL-2 HIL-2 was eluted in a single peak at 100% acetonitrile at 28 min. Optimum urea concentration was found to be 0.5 M and 24 h reaction time was sufficient without any additive such as CaCl2 and Tween-20.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.32 no.4 s.59
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• pp.241-247
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• 2006

This work was carried out to investigate the anti-inflammatory effects of Paulownia coreana Uyeki on abirritant, atopy and acne skin. Paulownia coreana Uyeki has been used as a traditional medicine having anti-febrile, anti-inflammation effect in Korea, Paulownia coreana Uyeki loaves were extracted with 70% EtOH. Its superoxide anion radical scavenging activity and inhibitory effect on LPS-induced NO production were examined. The extract inhibitied the generation of NO and $PGE_2$ induced by LPS in the macrophage cell line (Raw 264.7). Consistent with the inhibitory effects on No and $PGE_2$ generation, the extract inhibited expression of iNOS and COX-2. In further study, it was found that the extract prevented $IkB-{\alpha}$ degradation, as demonstrated by western blot analysis of $IkB-{\alpha}$ protein level. However, the extract treatment did not affect cell viability at $100{\mu}g/mL$ concentration in both human skin fibroblast and Raw 264.7 cells in vitro. Thus, the present study suggests that Paulownia coreana Uyeki leaves extract have significant anti-inflammatory activity and potential as an anti-irritation material.