• 청정기술
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• 제23권1호
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• pp.104-112
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• 2017

해조류로부터 수열 액화 반응을 통해 생성된 원료를 이용하여 수소가스를 생산하기 위해 개질 반응용 상용화 촉매와 $K_2Ti_xO_y$가 첨가된 니켈(Ni) 제조 촉매를 사용하여 반응온도에 따른 수증기 개질 반응을 수행하였다. 반응원료는 해조류 바이오매스를 503 K의 반응온도에서 2시간 동안 수열 액화를 통해 생성된 액화 원료를 사용하였으며, 상용화 촉매(FCR-4-02)와 제조 촉매($Ni/K_2Ti_xO_y-Al_2O_3$, $Ni/K_2Ti_xO_y-SiO_2$, $Ni/K_2Ti_xO_y-ZrO_2/CeO_2$, Ni/$K_2Ti_xO_y$-MgO) 및 반응온도에 따른 수증기 개질 반응의 활성을 비교 연구하였다. 실험결과 제조 촉매 4종 모두 상용화 촉매와 비교하여 반응활성이 높게 나타나는 것이 확인되었으며, 제조 촉매의 지지체에 따라 생성되는 가스의 조성이 달라지는 것이 확인되었다. 특히, 산성이나 염기성을 띄는 $Al_2O_3$와 MgO의 지지체와 중성을 띄는 $SiO_2$의 지지체에서는 CO가 선택적으로 높게 생성이 되었으며 환원성을 띄는 $CeO_2$를 포함하는 지지체에서는 수성가스 전환 반응이 일어나 $CO_2$가 높게 생성됨을 보였다.

• Bulletin of the Korean Chemical Society
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• 제32권9호
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• pp.3281-3289
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• 2011

The materials composed of the 3d series transition metals are introduced into the hydrocarbon steam-reforming reaction in order to enhance the $H_2$ production and abruptly depress the catalytic deactivation resulting from the strong sintering between the Ni component and the ${\gamma}-Al_2O_3$ support. The conventional impregnation method is used to synthesize the Ni/3d series metal/${\gamma}-Al_2O_3$ materials through the sequentially loading Ni source and the 3d series metal (Ti, V, Cr, Mn, Fe, Co, Cu, and Zn) sources onto the ${\gamma}-Al_2O_3$ support. The Mnloaded material exhibits a significantly higher reforming reactivity than the conventional Ni/${\gamma}-Al_2O_3$ and the other Ni/3d series metal/${\gamma}-Al_2O_3$ materials. Particularly the addition of Mn selectively improves the $H_2$ product selectivity by eliminating the formation of $CH_4$ and CO. The $H_2$ production is maximized at a value of 95% over Ni(0.3)/Mn(0.3)/${\gamma}-Al_2O_4$(1.0) with a butane conversion of 100% above $750^{\circ}C$ for up to 55 h.

• 한국수소및신에너지학회논문집
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• 제19권6호
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• pp.514-519
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• 2008

In the present study, biomass pyrolysis was done using five different kinds of catalysts with change in the support species and their compositions. Ni was loaded on alumina, ceria and alumina-ceria supports using co-precipitation method. In all the catalysts, 30wt% of nickel was loaded on the support materials. The paper used in daily writing purposes was taken into account as biomass sample. In the experiment, 19 of biomass was mixed with o.1g of each catalyst separately. Thermogravimetric analysis (TGA) was performed with all the catalysts diminished the initial degradation temperature of paper biomass sample considerably. During the pyrolysis process, the temperature was raised from room temperature to $800^{\circ}C$ with the heating rate of $10^{\circ}C$/min in the furnace. The cumulative $H_2$ volume had reached the best value of l4.02ml with the Ni/$Al_2O_3-CeO_2$ 30wt%/(50wt%-50wt%) catalysts. In presence of all the catalysts, the highest amount of $H_2$ was produced at $800^{\circ}C$, 10min. of residence time.

• 한국수소및신에너지학회논문집
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• 제14권1호
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• pp.69-80
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• 2003

Nickel catalyst has been used for natural gas reforming with carbon dioxide, In this study, catalyst support used was HY zeolite. The optimum loading of Ni in the catalysts was 13 wt%. The effect of promoters, such as Mg, Mn, and K, was also studied. The addition of promoters to Ni catalyst improved the stability of catalysts and carbon deposition on Ni catalyst was suppressed. The reforming reactivity of promoter-added Ni catalyst was higher than that of Ni catalyst without any promoters. SEM, XRD, BET, TGA and FTIR tests were tried to characterize the catalyst structure before and after reaction.

• Toxicological Research
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• 제17권4호
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• pp.255-265
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• 2001

Epidemiologic studies have demonstrated an association between short-term exposure to particulate air pollutants and increased mortality. However the biological mechanism underlying these associations have not been fully established and also the chemical and physical characteristics of the pollutant particles are not well understood. The metal constituents of air pollutant particles and their bioavailability are considered to Play an important role as possible mediators of Particle-induced airway injury and inflammation. Sprague-Dawley rat alveolar macrophage cells (NR8383) were exposed to airborne and acid-leached particulate matter (PM). Titanium oxide and nickel subsulfide were used as negative and positive controls. Particle-induced reactive oxygen species formation in cells was detected using the fluorescent probe 2',7'-dichlorofluorescin diacetate. Expression of TNF-$\alpha$ and IL-6 were measured by enzyme-linked immunosorbent assay, and PM-induced DNA double-strand breaks were determined with $\lambda$DNA/Hind III marker. Metals associated with air pollutant particles mediated intracellular oxidant production in alveolar macrophages, and the cytotoxicity and proinflammatory cytokine production induced by PM were associated with oxidative stress. The oxidants produced by air pollutant particles also are likely to induce DNA double-strand breaks. Our findings in alveolar macrophage cells exposed to PM and acid-leached PM support the hypothesis that metal components in urban air pollutants and their bioavailabilities might play an Important role in the induction of the adverse health effects.

• 공업화학
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• 제8권3호
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• pp.543-549
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• 1997

니켈(Ni)이 담지된 촉매상에서 이산화탄소와 부탄의 직접반응에 의한 합성가스와 탄화수소화합물의 생성을 검토하였다. $CO_2$와 $C_4H_{10}$의 반응에서 니켈 담지촉매는 백금 담지촉매와 유사한 활성을 나타내었으며, 부탄의 탈수소에 따큰 코크의 누적이 현저하게 나타났다. 담체로 알루미나나 Y형 제올라이트를 사용하면 일산화탄소와 수소가 주생성물이었다. 반면에 니켈을 ZSM-5형 제올라이트에 담지한 경우에는 생성물 중에 다량의 방향족화합물이 얻어졌다. Ni/ZSM-5, Ni/NaY 및 Ni/알루미나 촉매상에서 반응물 중의 이산화탄소/부탄 몰비의 증가와 함께이산화탄소의 전환율도 증가하다가 2이상에서 다시 감소하였다. 담체로 ZSM-5를 사용하고 이에 담지되는 니켈의 양을 다르게 하였을 때, 반응물의 전환율은 니켈금속의 담지량이 5wt% 부근에서 가장 높았다. 코크가 누적된 촉매상에 $CO_2$ 가스나 수증기를 흘리면 코크의 양은 감소하였다. 촉매상에 누적된 코크는 활성이 높은 상태로 결합되어 있으며, 표면의 활성탄소는 반응의 중요한 중간체로 작용하는 것으로 해석된다.

• 한국수소및신에너지학회논문집
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• 제24권3호
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• pp.237-241
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• 2013

The correlation between NiO-YSZ microstructure and its electrical property used for SOFC anode was critically evaluated with image processing and direct measurement techniques. These innovative processing techniques were employed to quantify the contiguity of the anode constituent phase. The calculated contiguities were then correlated with electrical conductivity attained from 4-probe DC method. This investigation described that contiguity of nickel oxide phases of an anode has a linear relationship with its electrical conductivity. We observed that the contiguity of NiO increased from 0.18 to 0.50 then electrical conductivity attained was significantly increased from 520 S/cm to 1468 S/cm at $900^{\circ}C$.

• 공업화학
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• 제2권1호
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• pp.47-55
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• 1991

탄소침적된 수소첨가반응용 Ni 촉매의 활성재생에 관하여 연구하였다. 침적된 탄소는 여러 가지 농도의 산소로 산화시켜 제거하였으며, 촉매의 활성은 아닐린 수소첨가반응을 model 반응으로 하여 측정하였다. 탄소침적된 촉매를 산화처리할 경우 처리온도가 증가함에 따라 표면적이 증가하다가 감소하는 현상을 보였으며, 최대 표면적을 나타내는 처리온도는 처리 산소농도가 감소함에 따라 증가하였다. 처리 산소농도가 높을수록 침적탄소의 산화에 의한 반응열로 인하여 Ni 입자의 소결현상 및 담체의 기공감소가 심하게 나타났다. 5 % 산소로 처리한 촉매의 경우, 촉매의 활성이 약 90% 까지 회복되었으나 20% 산소로 처리한 촉매의 경우, 활성의 회복을 기대할 수 없었다. 5 % 산소로 재생처리할 경우, 촉매의 활성은 산화처리 시간이 증가할수록 증가하였으나, 1 시간 이후에는 거의 일정하였다.

• 자원환경지질
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• 제51권3호
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• pp.291-307
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• 2018

호주는 금, 니켈, 철광석, 연, 아연 및 우라늄 매장량이 세계 1위를 차지하고 있으며, 다른 많은 주요광물 매장량에서도 세계 5위권이다. 호주의 현재 개발 중인 대부분의 광상은 수십년전에 발견이 용이했던 지표 천부에 배태된 광상이다. 최근 호주는 광물자원탐사에 대한 투자의 국제경쟁이 치열해지고 있으며, 많은 지역에서 그간 운영되었던 광산의 채산성이 악화되어, 지역경제를 견인할 주체를 상실하는 어려움에 직면하고 있다. 그러나 4차산업혁명에 따른 광물수요증가 추세를 감안할 때, 우리나라도 자원부국에서 스마트/디지털 광산개발 및 ICT 융합에 의한 탐사기술개발 확보로 자원기술 경쟁력을 갖출 기회라고 여겨진다.

• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1265-1272
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• 2007

A solid acid catalyst, NiSO4/CeO2-ZrO2 was prepared simply by promoting ZrO2 with CeO2 and supporting nickel sulfate on CeO2-ZrO2. The support of NiSO4 on ZrO2 shifted the phase transition of ZrO2 from amorphous to tetragonal to higher temperatures because of the interaction between NiSO4 and ZrO2. The surface area of 10-NiSO4/1-CeO2-ZrO2 promoted with CeO2 and calcined at 600 oC was very high (83 m2/g) compared to that of unpromoted 10-NiSO4/ZrO2 (45 m2/g). This high surface area of 10-NiSO4/1-CeO2-ZrO2 was due to the promoting effect of CeO2 which makes zirconia a stable tetragonal phase as confirmed by XRD. The role of CeO2 was to form a thermally stable solid solution with zirconia and consequently to give high surface area and acidity of the sample, and high thermal stability of the surface sulfate species. 10-NiSO4/1- CeO2-ZrO2 containing 1 mol% CeO2 and 10 wt% NiSO4, and calcined at 600 oC exhibited maximum catalytic activities for both reactions, 2-propanol dehydration and cumene dealkylation.