• 공업화학
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• 제5권3호
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• pp.509-516
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• 1994

에탄올의 제조시 불순물로서 미량 생성되는 크로톤 알데히드를 수소와 반응시켜 n-부틸알콜로 전환하여 불포화 탄화수소를 제거하는 공정에 액상수소 첨가반응을 이용하고자 하며, 기존의 기상 수소첨가반응보다 월등한 에너지 절약 효과가 있다. 반응촉매는 내구성 및 가격 등 경제적인 측면을 고려하여 니켈촉매를 선택하였으며, 반응전화율의 측정은 PMT(permanganate time) test 방법을 적용하였다. PMT는 에탄올에 미량으로 함유되어 있는 크로톤알데히드의 초기농도 증가에 따라 급격히 감소하였으며, 크로톤 알데히드로부터 n-부틸알콜로의 수첨반응은 탄소-탄소 이중결합의 환원 후, 알데히드의 환원 과정이 연속적으로 일어나고, 각 반응단계는 0차 반응속도 상수를 가진다. 실험조건 범위 내에서는 반응 온도가 높을수록, LHSV가 느릴수록 PMT는 길어지고, 반응압력은 PMT와 거의 무관함을 보였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.89-92
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• 2007

Partail oxidation(POX) of n-butane was investigated in this research by employing ceria-promoted Ni/calcium hydroxyapatite catalysts ($Ce_xNi_{2.5}Ca_{10}(OH)_2(PO_4)_6$ ; x = $0.1{\sim}0.3$) which had recently been reported to exhibit good catalytic performance in POX of methane and propane. The experiments were carried out with changing ceria content, $O_2/n-C_4H_{10}$ ratio and temperature. As the $O_2/n-C_4H_{10}$ feed ratio increased up to 2.75, n-$C_4H_{10}$ conversion and $H_2$ yield increased and the selectivity of methane and other hydrocarbons decreased. But with $O_2/n-C_4H_{10}$ = 3.0, $n-C_4H_{10}$ conversion and $H_2$ yield decreased. This is considered due to that too much oxygen may inhibit the reduction of Ni or induce the oxidation of Ni, which results in poor catalytic activity. The optimum $O_2/n-C_4H_{10}$ ratio lay between 2.50 and 2.75. $Ce_{0.1}Ni_{2.5}Ca_{10}(OH)_2(PO_4)_6$ showed the highest $n-C_4H_{10}$ conversion and $H-2$ yield on the whole. In durability tests, higher hydrogen yield and better catalyst stability were obtained with the $O_2/n-C_4H_{10}$ ratio of 2.75 than with the ratio of 2.5.

• 폴리머
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• 제29권4호
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• pp.338-343
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• 2005

Chloride계 전이금속 촉매의 존재 하에서 ABS/PC/triphenyl phosphate 컴파운드의 열분해 거동을 TGA(thermogravimetric analysis)를 통해서 조사하였다. Chloiide계 전이금속 촉매(cobalt chloiide, ferric chloride, nickel chloride 및 zinc chloride)는 ABS/PC/triphenyl phosphate 컴파운드의 열분해 과정에서 화학반응을 야기하여, 질소분위기에서 숯(char) 형성이 관찰되었으며, $600^{circ}C$에서 $3\~l3\%$의 비휘발성 눈을 형성하였다. 이와 같은 질소분위기에서의 ABS/PC/triphenyl phosphate 컴파운드의 숯 생성은 chloride계 전이금속 촉매의 가교효과(crosslinking effect)로 추정된다. 한편, 공기분위기에서는 생성된 숯은 고온 산화반응에 의해서 역분해되었다.

• 공업화학
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• 제3권2호
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• pp.230-239
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• 1992

알칼리형 연료전지의 수소극을 제작하기 위해 니켈을 사용하였다. 분극곡선을 측정한 결과 최적의 전해질 농도와 운전온도 조건은 6N KOH와 $80^{\circ}C$였다. 다양한 양의 PTFE 현탁액을 첨가하며 제조한 수소극에서의 전도도와 겉보기기공도 및 전류밀도를 비교한 결과 10wt%의 PTFE를 첨가하는 경우가 가장 적당함을 알았다. CO 화학흡착량으로부터 표면적을 구했으며 10wt%의 PTFE를 침적시키고 $340^{\circ}C$에서 소결시켜 제조한 수소극의 경우 $200mA/cm^2$ 이상의 전류밀도를 나타내었다. 전극의 표면구조를 SEM으로 관찰하였고 cold pressing, hot pressing, rolling 및 calendering 방법 등의 전극제작방법에 따른 전기화학적 특성을 고찰하였다.

• Korean Chemical Engineering Research
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• 제46권5호
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• pp.868-874
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• 2008

실리카, 알루미늄 실리케이트, 감마 알루미나 담체에 $Ni(NO_3)_2{\cdot}6H_2O$와 $Ni(CH_3COO)_2{\cdot}4H_2O$를 원료로 침전제인 요소와 시트르산을 사용하여 $90^{\circ}C$에서 공침법을 사용하여 흡착제를 제조하였으며 이를 환원시켜 일산화탄소 제거 실험을 수행하였다. 흡착제는 EDS, TPR, XRD 분석을 실시하여 이를 근거로 흡착제의 성능을 해석하였다. 침전제의 종류, 니켈 금속의 담지량, 담체, 니켈 금속의 염, 수소 환원 조건을 변화시켜 최적의 흡착 성능을 보이는 흡착제를 사용하여 실험을 수행하였다. 침전제인 요소에 $Ni(NO_3)_2{\cdot}6H_2O$를 사용하여 실리카 담체에 니켈 54.8 wt%를 담지하여 제조한 흡착제를 $500^{\circ}C$에서 3시간 수소 환원 전처리 후 흡착 실험을 하였을 때 가장 효과적으로 일산화탄소를 제거함을 확인하였다.

• 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.

• 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.

• 한국응용과학기술학회지
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• 제33권1호
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• pp.195-203
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• 2016

Heavy metals have been analyzed on the non-woven from the 24 kinds of wet wipes and 8 kinds of mask packs. The following materials used in the non-woven according to each product are: rayon+polyester for the 12 wet wipe products, rayon+PET for the 5 wet wipe products, and rayon, cotton, rayon+polyester+cotton, pulp+polypropylene for the rest of the wet wipe products. No further information on the materials was found on the 3 wet wipes and 8 mask packs. However, polyester may be applied for the non-woven in wet wipes, because PET is part of the polyester group. The heavy metals analysis in the 24 kinds of wet wipes and 8 kinds of mask packs revealed the following: arsenic was found from $47.14{\pm}1.13$ to $71.75{\pm}1.64{\mu}g/L$ on the 3 products, the amount of nickel in the 2 products were $261.26{\pm}5.14$ and $1,242.63{\pm}43.71{\mu}g/L$, $53.69{\pm}1.45$ and $103.52{\pm}2.02mg/L$ on the 2 mask packs. It was also revealed that lead was detected from $7.23{\pm}0.32$ to $55.67{\pm}1.46{\mu}g/L$ on the 6 wet wipes, antimony was ranged from $187.86{\pm}5.24$ to $19,558.35{\pm}3,537.30{\mu}g/L$ on the 12 wet wipes, and $5.25{\pm}0.25$ and $8,936{\pm}55.22{\mu}g/L$ on the 2 mask packs. No cadmium, mercury, or thallium were detected from all the products. A high concentration of antimony might come from antimony trioxide, which was used as a catalyst when manufacturing the polyester. Therefore, it is strongly recommended that a non-woven used for cosmetic purposes should not use heavy metals as a catalyst when manufacturing, and it's important to clarify which materials are used in non-woven.

• 한국결정성장학회지
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• 제16권6호
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• pp.256-259
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• 2006

Vapor phase epitaxy(VPE)법을 사용하여 amorphous $SiO_x$. nanowires를 성장시켰다. Ni thin film을 촉매로 사용하여 Si 기판위에 $800{\sim}1100^{\circ}C$ 범위의 온도에서 성장시켰으며, $SiO_x$ nanowires의 성장 메커니즘은 Vapor-liquid-solid(VLS)으로 확인되었다. $SiO_x$ nanowires의 shape와 morphology는 scanning electron microscope(SEM)으로 분석하였으며, cotton-like형태이고 길이는 $10{\mu}m$정도였다. 그리고 구조적 특징은 transmission electron microscope(TEM)으로 관찰하였고, $SiO_x$ nanowires의 성분 분석은 energy dispersed X-ray spectroscopy(EDS)로 하였다. EDX spectrum으로 nanowires가 Si와 O로 구성되어졌음을 확인하였다.

• 한국수소및신에너지학회논문집
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• 제34권5호
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• pp.421-430
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• 2023

Fe-Ni-Pt nanocatalysts were loaded on carbon black powders which were synthesized by a spontaneous reduction reaction of iron (II) acetylacetonate, nickel (II) acetylacetonate and platinum (II) acetylacetonate. The morphology and the loading weight of Fe-Ni-Pt nanoparticles were characterized by transmission electron microscopy and thermogravimetric analyzer. The amount of Fe-Ni-Pt catalyst supported on the carbon black surface was about 6.42-9.28 wt%, and the higher the Fe content and the lower the Pt content, the higher the total amount of the metal catalyst supported. The Brunauer-Emmett-Teller Analysis (BET) specific surface area of carbon black itself without metal nanoparticles supported was 233.9 m²/g, and when metal nanoparticles were introduced, the specific surface area value was greatly reduced. This is because the metal nanocatalyst particles block the pore entrance of the carbon black, and thereby the catalytic activity of the metal catalysts generated inside the pores is reduced. From the I-V curves, as the content of the Pt nanocatalyst increased, the electrolytic properties of water increased, and the activity of the metal nanocatalyst was in the order of Pt > Ni > Fe.