• 대한화학회지
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• 제55권5호
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• pp.830-834
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• 2011

This paper is on the industrial synthesis process of anti-oxidant RD ((2,2,4-trimethyl-1,2-dihydroquinoline polymer $(C_{12}H_{15}N)_n$. n=2-4)).The content of dimer, trimer and tetramer of RD as the inspection targets, using the orthogonal design method - take the ratios of keto-amine, the reaction time, the reaction temperatures and the ratios of catalyst acid-amine as inspect factors - to optimized the reaction condition. The results indicate that the best ratio of keto-amine is 2:1, the time of salification and condensation is 3 hours and 7.5 hours. The range of temperature of salification and condensation is $135^{\circ}C$ and $120-125^{\circ}C$, and that the best ratio of acid-amine is 0.2: 1 (the proportion is the concentration ratio for mole). Under the optimization conditions, the yield of RD was stabilized and content of RD more than 45%.

• 공업화학
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• 제24권4호
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• pp.412-415
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• 2013

상온 이온성액체 중 하나인 1-hexyl-3-methylimidazolium tetrafluoroborate을 이용하여 팔라듐이 담지된 탄소입자를 제조하였다. 제조된 입자는 hexafluoropropylene (HFP) 수소화 반응용 촉매로 사용되었다. 또한 최적의 수소화 반응공정을 개발하기 위하여 다양한 반응조건에서 반응을 수행하였다. 팔라듐의 함량의 경우 3 wt% 이상을 유지하고 이온성액체와 팔라듐전구체의 몰비가 1 : 1로 합성된 촉매가 우수한 수소화 반응성을 보였다. 반응조건의 경우 수소와 HFP의 유량비가 1.25 이상이고 $GHSV_{HFP}$는 50000 mL/g-h 이하일 때 전환율 100%를 달성하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.98.2-98.2
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• 2013

Electrochemical phenomena underpin a broad spectrum of energy, chemical, and information technologies such as resistive memories and secondary batteries. The optimization of functionalities in these devices requires understanding electrochemical mechanisms on the nanoscale. Even though the nanoscale electrochemical phenomena have been studied by electron microscopies, these methods are limited for analyzing dynamic electrochemical behavior and there is still lack of information on the nanoscale electrochemical mechanisms. The alternative way can be an atomic force microscopy (AFM) because AFM allows nanoscale measurements and, furthermore, electrochemical reaction can be controlled by an application of electric field through AFM tip. Here, I will summarize recent studies to probe nanoscale electrochemical reaction in battery applications by AFM. In particular, we have recently developed electromechanical based AFM techniques for exploring reversible and irreversible electrochemical phenomena on the nanoscale. The present work suggests new strategies to explore fundamental electrochemical mechanisms using the AFM approach and eventually will provide a powerful paradigm for probing spatially resolved electrochemical information for energy applications.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2008년도 제39차 학술발표회
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• pp.117-118
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• 2008

The main objectives of this study are develop an Electro-Chemical process for dyeing wastewater treatment. In this work, We are investigated to optimization of electro-chemical process condition such as pH, additives(NaCl), reaction time, current density. As a result, About 89% of color(influent 452.5 ptco. unit) was removed by Electro-Chemical process using type C $SnO_2$ electrode. This results are promising potential for dyeing wastewater treatment.

• 공업화학
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• 제10권2호
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• pp.293-298
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• 1999

Fluoran계 감열색소의 중간체인 2-Methyl-4-methoxydiphenylamine(MMDPA)을 합성하는 촉매반응의 반응기구를 규명하고 반응조건을 최적화하였다. 반응물질로서는 2-methyl-4-methoxyaniline(MMA), 3-methyl-4-nitroanisole(MNA), 그리고 cyclohexanone의 혼합물을 사용하였으며, 5 wt % Pd/C를 촉매로 사용하였다. 반응실험은 reflux condenser가 부착된 개방형 slurry reactor에서 진행시켰으며, 생성물은 GC/MS와 NMR에 의해서 분석하였다. 반응조건을 최적화 시킨 결과 xylene용매 속에서 0.01 gmoles MMA 투입기준으로 MMA : MNA : cyclohexanone = 1 : 2 : 150의 반응물조성, $160^{\circ}C$의 반응온도, 0.5 g 촉매량 조건에서 8~10시간 경과 후 90 mole %의 MMDPA수율을 얻을 수 있었다. MMA와 cyclohexanone간의 축합반응에 의해 생성된 중간생성물의 탈수소화 반응단계가 총괄반응을 율속함을 알 수 있었다. MNA를 MMA와 함께 반응물에 투입함으로써 hydrogen transfer반응에 의하여 총괄반응속도와 MMDPA수율이 증대되었다. 반응물에 과량으로 투입된 cyclohexanone은 MMA와의 축합반응을 촉진시키는 역할을 하였다.

• Advances in Energy Research
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• 제1권2호
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• pp.147-163
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• 2013

The world faces several issues of energy crisis and environmental deterioration due to over-dependence on single source of which is fossil fuel. Though, fuel is needed as ingredients for industrial development and growth of any country, however the fossil fuel which is a major source of energy for this purpose has always been terrifying thus the need for alternative and renewable energy sources. The search for alternative energy sources resulted into the acceptance of a biofuel as a reliable alternative energy source. This work presents the study of optimization of process of transesterification of vegetable oil to biodiesel using NaOH as catalyst. A $2^4$ factorial design method was employed to investigate the influence of ratio of oil to methanol, temperature, NaOH concentration, and transesterification time on the yield of biodiesel from vegetable oil. Low and high levels of the key factors considered were 4:1 and 6:1 mole ratio, 30 and $60^{\circ}C$ temperatures, 0.5 and 1.0 wt% catalyst concentration, and 30 and 60 min reaction time. Results obtained revealed that oil to methanol molar ratio of 6:1, tranesetrification temperature of $60^{\circ}C$, catalyst concentration of 1.0wt % and reaction time of 30 min are the best operating conditions for the optimum yield of biofuel from vegetable oil, with optimum yield of 95.8%. Results obtained on the characterizzation of the produced biodiesel indicate that the specific gravity, cloud point, flash point, sulphur content, viscosity, diesel index, centane number, acid value, free glycerine, total glycerine and total recovery are 0.8899, 4, 13, 0.0087%, 4.83, 25, 54.6. 0.228mgKOH/g, 0.018, 0.23% and 96% respectively. Results also indicate that the qualities of the biodiesel tested for are in conformity with the set standard. A model equation was developed based on the results obtained using a statistical tool. Analysis of variance (ANOVA) of data shows that mole ratio of ground nut oil to methanol and transesterification time have the most pronounced effect on the biodiesel yield with contributions of 55.06% and 9.22% respectively. It can be inferred from the results various conducted that vegetable oil locally produced from groundnut oil can be utilized as a feedstock for biodiesel production.

• 공업화학
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• 제34권2호
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• pp.137-143
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• 2023

본 연구에서는 알팔파로부터 추출한 천연계면활성제를 사용하여 중심합성설계모델(CCD-RSM)을 이용한 O/W 유화제조 공정의 최적화를 수행하였다. 그 결과 95% 신뢰구간에서 최적화 결과의 통계학적 합리성을 확인하였다. CCD-RSM을 통하여 독립변수인 알팔파 추출물:Sugar ester S-370의 혼합비율(P), 계면활성제의 첨가량(W) 및 유화속도(R)가 반응치인 유화안정도지수(ESI), 평균입자크기(MDS) 및 점도(V)에 끼치는 영향을 조사하여 O/W 유화제조공정의 최적조건을 산출하였다. 유화안정도지수, 평균입자크기 및 점도에 관한 회귀방정식으로부터 다중반응을 수행하여 3가지 반응치를 동시에 만족하는 최적 유화조건으로 알팔파 추출물:Sugar ester S-370의 혼합비율은 49.5 wt%, 계면활성제의 첨가량 9.1 wt%, 유화속도 6559.5 rpm으로 나타났으며 산출된 반응치의 응답값은 ESI는 89.9%, MDS는 1058.4 nm, V는 1522.5 cP로 산출되었다. 이를 실험으로 확인한 결과 ESI는 88.7%, MDS는 1026.4 nm, V는 1486.5 cP이었으며 평균 오차율은 2.3 (± 0.4)%이었다. 따라서 CCD-RSM을 실제 유화 제조에 적용하여 만족스러운 O/W 유화제조 공정조건을 얻을 수 있었다.

• 에너지공학
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• 제29권1호
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• pp.58-62
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• 2020

연소 배기가스 중 온실가스의 원인이 되는 이산화탄소를 회수하여 활용하며 상업적으로도 가치가 큰 프로필렌카보네이트(Propylene Carbonate)를 합성하는 연구를 수행하였다. 상업적으로 프로필렌카보네이트 생산 적용이 가능한 균일계 유기 촉매와 반응 조건을 이용하여 pilot scale로 실험을 진행하였으며, 상업적으로 적용 가능한 최적의 촉매 및 농도, 반응 온도 및 압력등의 공정조건을 확립 할 수 있었다. 환경 친화적인 공법이며, 촉매 제조에 가격 경쟁력이 있고, 촉매는 재사용이 가능하며, 기존 대비 낮은 온도 및 압력의 반응 조건으로 95% 이상의 높은 전환율과 99%이상의 순도로 제조 가능하기에 상업적으로 충분히 적용 가능한 공정임을 확인 할 수 있었다.

• Korean Chemical Engineering Research
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• 제58권2호
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• pp.293-300
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• 2020

홍조류인 Eucheuma spinosum은 카라기난을 주된 다당으로 함유하고 있으며 Indonesia, Malaysia, Philippines, China, Tanzania 등지에서 상업적으로 생산되고 있다. 본 연구에서는 E. spinosum을 대상으로 FeCl₃-촉매 수열반응을 통하여 당과화학중간체(5-HMF, levulinic acid, formic acid)로전환하고자하였다. 통계적실험법(3-수준-3-인자의 Box-Behnken design)을 적용하여 반응인자(반응온도, 촉매농도, 반응시간)의 최적화와 영향을 평가하였다. 최적화 결과, 5-HMF의 농도는 160 ℃, 0.4 M FeCl₃, 10 min에서 2.96 g/L가 생성되었다. Levulinic acid와 formic acid의 최적 조건은 200 ℃, 0.6 M FeCl₃, 30 min으로 결정되었고, 농도는 각각 4.26 g/L와 3.77 g/L이었다.

• 한국환경과학회지
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• 제6권4호
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• pp.399-407
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• 1997

The pyrolysis reactions of atomic hydrogen with chloroform were studied In a 4 cm 1.6. tubular flow reactor with low flow velocity 1518 cm/sec and a 2.6 cm 1.4. tubular flow reactor with high flow velocity (1227 cm/sec). The hydrogen atom concentration was measured by chemiluminescence titration with nitrogen dioxide, and the chloroform concentrations were determined using a gas chromatography. The chloroform conversion efficiency depended on both the chloroform flow rate and linear flow velocity, but 416 not depend on the flow rate of hydrogen atom. A computer model was employed to estimate a rate constant for the initial reaction of atomic hydrogen with chloroform. The model consisted of a scheme for chloroform-hydrogen atom reaction, Runge-Kutta 4th-order method for Integration of first-order differential equations describing the time dependence of the concentrations of various chemical species, and Rosenbrock method for optimization to match model and experimental results. The scheme for chloroform-hydrogen atom reaction Included 22 elementary reactions. The rate constant estimated using the data obtained from the 2.6 cm 1.4. reactor was to be 8.1 $\times$ $10^{-14}$ $cm^3$/molecule-sec and 3.8 $\times$ $10^{-15}$ cms/molecule-sec, and the deviations of computer model from experimental results were 9% and 12% , for the each reaction time of 0.028 sec and 0.072 sec, respectively.