• Journal of the Korean Wood Science and Technology
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• 제14권3호
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• pp.43-46
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• 1986

A stainless steel autoclave reactor, which is the property of Pacific Northwest Laboratories(PNL) and located in PNL, was acted for pyrolysis and gasification of sawdust, ricestraw, and ricehusk. The initial reaction temperature of this reactor was 300$^{\circ}C$, and up to 500$^{\circ}C$ to complete pyrolysis and gasification reaction. The maximum exerted pressure on this reactor was 800 psig. In order to examine the effect of catalyst on reaction temperature, $K_2CO_3$, and nickel/alkali carbonate catalyst mixture were also used. The experimental results obtained with this reactor indicated that good yields of methane-rich gas(exceeding 40% methane) can be produced. The product gas mixtures were also identified to be CO. $CO_2$, $C_2H_4$, and $CH_3CHO$ etc. by Gas Chromatography and Mass Spectrometer.

• 대한안전경영과학회지
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• 제21권1호
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• pp.17-23
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• 2019

The diesel engine generate many pollutants such as PM(Particulate matter) and NOx(Nitrogen oxide). So the SCR(Selective catalytic reduction) must be required to meet the emission standard. The SCR catalyst market is growing rapidly, and the automobile markets using alternative energy sources are growing rapidly. This study deals with optimization of the calcination process the manufacturing process of SCR catalyst to be competitive. The calcination process is a bottleneck and it is required to optimize productivity and accept to be safety, But we cannot trade off anything in terms of safety. We applied DOE(Design of experiments) among many research methods performed in various fields. In order to achieve quality and productivity optimization. The dependent variables in the DOE were selected as NO Conversion(%). The independent variables were selected as the calcination temperature, soaking time and fan speed RPM. the CCD(Central composite designs) constructs response surface using the data onto experience and finds optimum levels within the fitted response surfaces. Our tests are our stability guarantee and efficient together with operation.

• Membrane and Water Treatment
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• 제7권2호
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• pp.143-154
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• 2016

Acetic acid can be removed from wastewater by esterification in a membrane reactor. Pervaporation membrane reactor (PVMR) is an alternative process to conventional separation processes. It is an environmentally friendly process. The main advantages of the PVMR are simultaneous water removal and production of an ester economically. In this study, the synthetic wastewater has been used. Esterification reaction of acetic acid with isopropanol has been studied in the presence of tungstosilicic acid hydrate as a catalyst in a batch reactor and in a PVMR. The effects of important operating parameters such as reaction temperature, initial molar ratio of isopropanol to acetic acid and catalyst concentration has been examined. Removal of acetic acid (conversion of acetic acid) was obtained as 85% using a PVMR by removal of water from the reaction mixture.

• Bulletin of the Korean Chemical Society
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• 제26권9호
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• pp.1410-1414
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• 2005

Neopentyl arenesulfonates reacted with primary alkylmagnesium halides in the presence of $(PPh_3)_2NiCl_2$ to produce the corresponding alkylarenes. The efficiency of this coupling reaction considerably depends on the nature of catalyst and solvent. Highest yield was obtained by using three equivalents of Grignard reagent to a mixture of $(PPh_3)_2NiCl_2$ and arenesulfonate in refluxing $Et_2O$. This reaction represents a novel method allowing the efficient and creative substitution of sulfur-containing groups in aromatic compounds. It also shows that the alkyloxysulfonyl group might be a suitable alternative to halides and triflate in some circumstances.

• 대한화학회지
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• 제53권5호
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• pp.536-541
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• 2009

무용제하에서 $\alpha$-히드록시 인산염을 합성하기 위해 술팜산은 비용효율이 높고 일반적인 산들의 친환경적인 대안으로 활용되었다. 초음파 조사를 이용하여 더 나은 수율을 얻었고 반응시간이 짧았다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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• pp.61-63
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• 2015

In the low pressure selective catalytic reduction (LP SCR) system, the uniformity of both ammonia concentration and exhaust gas flow at the SCR catalyst layer are important design factor for the efficient SCR-deNOx performance. According to the shape of the guide vane and static mixer, numerical simulations were conducted to analyze flow patterns and finally to find out the appropriate alternative for uniform flow at the front of catalyst in the real scale LP SCR reactor. The variations of gas velocity and ammonia concentration were quantitatively evaluated. Based on the present results, the shape was devised to satisfy the design criteria.

• 전기화학회지
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• 제10권4호
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• pp.295-300
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• 2007

A new characterization method using a porous plug model was proposed to determine the degree of sulfonation (DS) of ionomer binder with respect to the membrane used in membrane-electrode assemblies (MEAs) and to analyze the fraction of proton pathways through ionomer-catalyst combined electrodes in MEAs for polymer electrolyte fuel cells (PEFCs). Sulfonated poly(ether ether ketone) was prepared to use a polymeric electrolyte and laboratory-made SPEEK solution (5wt.%, DMAc based) was added to catalyst slurry to form catalyst layers. In case of the SPEEK-based MEAs in this study, DS of ionomer binder for catalyst layers should be the same or higher than that of the SPEEK membrane used in the MEAs. The porous plug model suggested that most of protons were via the ionomer binder (${\sim}92.5%$) bridging the catalyst surface to the polymeric electrolyte, compared with the pathways through the alternative between the interstitial water on the surface of ionomer binder or catalyst and the ionomer binder (${\sim}7.3%$) and through only the interstitial water on the surface of ionomer or catalyst (${\sim}0.2%$) in the electrode of the MEA comprising of the sulfonated poly(ether ether ketone) membrane and the 5wt.% SPEEK ionomer binder. As a result, it was believed that the majority of proton at both electrodeds moves through ionomer binder until reaching to electrolyte membrane. The porous plug model of the electrodes of MEAs reemphasized the importance of well-optimized structure of ionomer binder and catalyst for fuel cells.

• 청정기술
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• 제27권4호
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• pp.332-340
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• 2021

최근 사업장 질소산화물(NOx) 배출허용기준 강화(2019년 1월 적용)에 따라 다량 배출사업장에서 배출되는 질소산화물을 배출허용기준 이하로 만족하기 위한 노력이 필요하다. 대표적인 질소산화물 저감 방법으로 선택적 촉매 환원법(selective catalytic reduction, SCR)을 주로 사용하고 있으며, 일반적으로 세라믹 허니컴(ceramic honeycomb) 촉매를 사용하고 있다. 본 연구에서는 높은 열적 안정성과 기계적 강도를 가지는 금속지지체 탈질 코팅촉매를 적용하여 제철소에서 배출되는 질소산화물를 저감하기 위한 연구를 수행하였다. 금속지지체 코팅촉매는 최적화된 촉매슬러리(catalyst slurry) 코팅방법을 통해 제조하였고, 내마모 시험과 굽힙 시험을 통해 코팅된 촉매가 균일하고 강건하게 부착되어 있음을 확인하였다. 금속지지체가 가지는 우수한 열전도 특성으로 인해 저온영역(200 ~ 250 ℃)에서 세라믹 허니컴 촉매보다도 우수한 탈질효율을 보였다. 또한 경제적인 촉매 설계를 위해 금속지지체 표면 상에 코팅되는 촉매의 최적 코팅량을 확인하였다. 이러한 연구결과를 바탕으로 제철소 배기가스 모사환경에서 상용급 금속지지체 코팅촉매에 대한 준파일럿 탈질 성능평가를 수행하였고, 저온영역(220 ℃)에서도 배출허용기준치(60 ppm 이하)을 만족하는 우수한 성능을 나타내었다. 따라서 물리화학적 특성이 우수한 금속지지체 코팅촉매가 최소량의 촉매 사용으로도 우수한 탈질 성능을 나타내었으며, 넓은 비표면적을 가지는 고밀도 금속지지체 적용을 통해 배연 탈질 촉매 반응기의 콤팩트화 및 소형화가 가능하였다. 이러한 결과를 바탕으로, 본 연구에서 사용된 금속지지체 코팅촉매는 제철소뿐만 아니라 화력발전, 소각장, 선박, 건설기계 등 다양한 산업 분야에 적용할 수 있는 새로운 형태의 촉매가 될 것이다.

• Journal of the Korean Wood Science and Technology
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• 제14권2호
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• pp.21-28
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• 1986

목질물질(木質物質)인 톱밥, 볏짚 그리고 왕겨를 열분해(熱分解)하여 기상물질(氣相物質)을 합성(合成)하기 위해, 석영으로 설계 제작된 반응탑(反應塔)을 사용하였다. 최초의 반응온도 350$^{\circ}C$로부터 열분해(熱分解)와 gasification 반응(反應)이 완결된다고 예상되는 550$^{\circ}C$까지 가열하였다. 촉매가 반응온도에 어떤 영향을 미치는지 조사하기 위해 $K_2CO_3$와 $Na_2CO_3$를 촉매로 사용하였다. 합성(合成) gas chromatograph와 mass spectrometer에 의해 CO, $CO_2$, $CH_4$ 그리고 $CH_3CHO$등인 것으로 판명되었다. 합성(合成) gas의 수율(收率)과 조성(組成)은 반응온도(反應溫度)와 이 반응에 사용되는 촉매에 달려있지만, 톱밥을 시료(試料)로 반응온도 550$^{\circ}C$, $K_2CO_3$를 촉매로 사용한 반응(反應)에서 생성되는 gas 체적(體積)은 1,800$m{\ell}$/g 톱밥에 달한다.

• 융복합기술연구소 논문집
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• 제3권1호
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• pp.9-14
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• 2013

Recently, the development of renewable energy sources in Mongolia has been needed due to climate change and air pollution in Ulaanbaatar as rapid economic growth. Biodiesel can be considered as an alternative fuel for petroleum based diesel in order to decrease air pollution in Ulaanbaatar because of its no emission of particle materials from internal combustion engine in automobile. Rapeseed oil having low cloud point and pour point was suggested as a promising raw material for biodiesel production in Mongolia. Considering high population density and severe air pollution by particle materials and SOx in Ulaanbaatar, prior supplying site of biodiesel in Mongolia was the capital region including Ulaanbaatar. In the production of biodiesel in Mongolia, adsorption process was a effective alternative to washing process for the removal of residual alkali catalyst and reactants due to long winter time in Mongolia. For the stable supply of biodiesel, subsidy and no tax policy is needed in the early stage of biodiesel supply in Mongolia.