• 신재생에너지
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• 제5권2호
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• pp.9-14
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• 2009

Automobile Shredder Residue (ASR) is very appropriate in a gasification melting system. Gasification melting system, because of high reaction temperature over than $1,350^{\circ}C$, can reduce harmful materials. To use the gasification processes for hydrogen production, the high concentration of CO in syngas must be converted into hydrogen gas by using water gas shift reaction. In this study, the characteristics of shift reaction of the high temperature catalyst (KATALCO 71-5M) and the low temperature catalyst (KATALCO 83-3X) in the fixed - bed reactor has been determined by using simulation gas which is equal with the syngas composition of gasification melting process. The carbon monoxide composition has been decreased as the WGS reaction temperature has increased. And the occurrence quantity of the hydrogen and the carbon dioxide increased. When using the high temperature catalyst, the carbon monoxide conversion ratio ($1-CO_{out}/CO_{in}$) rose up to 95.8 from 55.6. Compared with average conversion ratio from the identical synthesis gas composition, the low temperature catalyst was better than the high temperature catalyst.

• 대한화학회지
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• 제61권1호
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• pp.7-11
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• 2017

The extended $H{\ddot{u}}ckel$ method is employed to analyze the interaction of carbon monoxide with the TiC(001) surfaces, both perfect and containing carbon vacancies. CO exhibits a similar ${\sigma}$-donation interaction for both $Ti_{25}C_{25}$ and $Ti_{25}C_{23}$ clusters, as deduced from the fact that the populations of the CO $5{\sigma}$ orbital are identical upon adsorption, but it bonds more strongly with the $Ti_{25}C_{23}$ than with the $Ti_{25}C_{25}$ because the metal d electron density in $Ti_{25}C_{23}$ provides ${\pi}$ back-bonding interactions with CO that are absent in $Ti_{25}C_{25}$. This work suggests that a difference in reactivity toward CO of stoichiometric TiC and TiC with carbon defects is connected with the occupancy of $2{\pi}^*$ orbitals that leads to a significant weakening of the C-O bond.

• Bulletin of the Korean Chemical Society
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• 제13권4호
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• pp.354-355
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• 1992

• 한국수소및신에너지학회논문집
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• 제32권4호
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• pp.197-204
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• 2021

Pressure swing adsorption is a purification process which can get pure hydrogen. The purification process is composed of four process: compression, adsorption, desorption and discharge. In this study the adsorption process was simulated by using the Fluent and validated with experimental results. A gas used in experiment is composed of H₂, CO₂, CH₄, and CO. Adsorption process conducted under 313 kelvin and 3 bar and bituminous-coal-based (BPL) activated carbon was used as the adsorbent. Langmuir model was applied to explain the gas adsorption. And diffusion of all the gases was controlled by micro-pore resistances. The result shows that, the most adsorbed gas was carbon dioxide, followed by methane and carbon monoxide. And carbon monoxide took the least amount of time to reach the maximum adsorption amount. The molar fraction of the off-gas became the same as the molar fraction of the gas supplied from the inlet after adsorption reached the equilibrium.

• 청정기술
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• 제28권1호
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• pp.9-17
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• 2022

전기화학적 이산화탄소 환원 기술은 전기에너지를 이용하여 대표적인 온실가스인 이산화탄소를 유용한 기초 화학제품으로 전환시킬 수 있는 유망한 기술 중 하나다. 특히, 다양한 후보 제품 중 일산화탄소는 높은 Faraday 효율과 우수한 경제성을 나타내기 때문에 학계와 산업계의 많은 관심을 받고 있다. 과거 여러 연구진이 본 기술의 온실가스 저감 잠재량을 정량적으로 분석했으나, 분석 과정에서 도입된 과정과 사용된 인벤토리 데이터의 일관성 및 투명성에 문제가 제기된다. 본 연구에서는 전기화학적 이산화탄소 환원을 통한 일산화탄소 생산 공정의 온실가스 저감 잠재량 분석을 위한 전과정평가를 수행했다. 세 종류의 시스템 경계를 정의 후 각각의 지구온난화지수를 화석연료 기반 일산화탄소 생산 공정과 비교했다. 분석 결과, 전기화학적 일산화탄소 생산 기술을 도입하여 온실가스를 저감하기 위해서는 전해조 구동에 필요한 전기에너지의 배출계수가 현재 국내 발전부문의 배출계수보다 충분히 낮아야 한다는 점을 확인했다. 또한, 신뢰성 있는 온실가스 저감 잠재량 분석을 위해서는 기존의 화석연료 기반 일산화탄소 생산 공정의 인벤토리 정보를 투명하게 공개하는 것이 중요함을 밝혔다.

• Journal of the Korean Data and Information Science Society
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• 제27권4호
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• pp.1001-1012
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• 2016

대기오염물질이 인간의 건강에 악영향을 미치는 사실은 잘 알려져 있다. 유엔 환경 계획 (united nations environment program; UNEP) 보고서에 따르면, 미세먼지와 일산화탄소 오염물질로 연간 전 세계에서 430만 명이 목숨을 잃었다. 일산화탄소는 탄소와 산소로 구성된 화합물로 가정에서 생성되는 독성 가스 중 가장 위험한 가스이다. 연구를 위하여 2004년부터 2013년까지 10년간 대구 경북 지역의 대기오염관측소에서 관측된 1시간, 6시간, 12시간, 24시간 평균 일산화탄소 농도 자료를 사용하였다. 일반화 극단치 분포의 모수는 최우추정법과 L-적률추정법을 통해 추정하였고 적합도 검정을 수행하였다. 본 연구의 표본 수가 크지 않으므로 L-적률추정법이 최대우도법에 비해 모수추정에 적합하였다. 또한, 5년, 10년, 20년, 40년 재현수준을 추정하여 대구 경북 지역 일산화탄소 위험지역을 살펴보았다.

• 한국재료학회지
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• 제26권12호
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• pp.741-750
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• 2016

Nanofibers(NFs), because of their high surface area and nanosized grains, have appropriate morphologies for use in chemiresistive-type sensors for gas detection applications. In this study, a highly sensitive and selective CO gas sensing material based on Au-decorated $SnO_2$ NFs was fabricated by electrospinning. $SnO_2$ NFs were synthesized by electrospinning and subsequently decorated with various amounts of Au nanoparticles(NPs) by sputtering; this was followed by thermal annealing. Different characterizations showed the successful formation of Au-decorated $SnO_2$ NFs. Gas sensing tests were performed on the fabricated sensors, which showed bell-shaped sensing behavior with respect to the amount of Au decoration. The best CO sensing performance, with a response of ~20 for 10 ppm CO, was obtained at an optimized amount of Au (2.6 at.%). The interplay between Au and $SnO_2$ in terms of the electronic and chemical sensitization by Au NPs is responsible for the great improvement in the CO sensing capability of pure $SnO_2$ NFs, suggesting that Au-decorated $SnO_2$ NFs can be a promising material for fabricating highly sensitive and selective chemiresistive-type CO gas sensors.

• 한국세라믹학회지
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• 제47권1호
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• pp.92-96
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• 2010

Based on the differential electrode equilibria approach, potentiometric YSZ sensors with semiconducting oxide electrodes for CO detection are developed. To improve the selectivity, sensitivity and response-time of the sensor, our strategy includes (a) selection of an oxide with a semiconducting response to CO, (b) addition of other semiconducting materials, (c) addition of a catalyst (Pd), (d) utilization of combined p- and n-type electrodes in one sensor configuration, and (e) optimization of operating temperatures. Excellent sensing performance is obtained by a novel device structure incorporating $La_2CuO_4$ electrodes on one side and $TiO_2$-based electrodes on opposite substrate faces with Pt contacts. The resulting response produces additive effects for the individual $La_2CuO_4$ and $TiO_2$-based electrodes voltages, thereby realizing an even higher CO sensitivity. The device also is highly selective to CO versus NO with minor sensitivity for NO concentration, compared to a notably large CO sensitivity.

• International Journal of Computer Science & Network Security
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• 제21권11호
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• pp.59-66
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• 2021

Many incidents of Carbon Monoxide (CO) poisoning have occurred because of people being unaware of its presence. There are currently available systems on the market, but they are limited to measuring CO in a certain area and lack vital functions. Additionally, little to no evidence-based information on their quality was available. Thus, a mobile application for detecting CO gas leakage in a vehicle and critical features to assist victims was developed. A usability and functionality test were conducted to determine the product's quality utilizing nine usability and six functionality task scenarios (n=5). Then, a System Usability Scale test was performed to obtain system satisfaction, usability, and learnability (n=50). The usability and functionality test shows that all the tasks given for both tests were 100% successful. The overall score obtained for SUS was 71.4, which indicates good acceptance and usability. Around 20% of respondents claimed that they would need the support of a technical person to be able to use the application and that they needed to learn a lot of things before they could use the application, which indicates the overall high learnability of the application. The result provides empirical evidence that the CO gas leakage detection mobile application is successful and receives good usability, functionality, acceptability, learnability, and satisfaction assessments. DetGas could benefit automobile owners and other stakeholders by mitigating the risk and harm associated with gas leaking that exceeds the safe limit.

• Nuclear Engineering and Technology
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• 제52권12호
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• pp.2836-2846
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• 2020

During severe nuclear power plant (NPP) accidents, a H₂/CO mixture can be generated in the reactor pressure vessel by core degradation and in the containment as well by molten corium-concrete interaction. In spite of its importance, a state-of-the-art methodology predicting H₂/CO combustion risk relies predominantly on empirical correlations. It is therefore necessary to develop a proper methodology for flammability evaluation of H₂/CO mixtures at ex-vessel phases characterized by three factors: CO concentration, high temperature, and diluents. The developed methodology adopted Le Chatelier's law and a calculated non-adiabatic flame temperature model. The methodology allows the consideration of the individual effect of the heat transfer characteristics of hydrogen and carbon monoxide on low flammability limit prediction. The accuracy of the developed model was verified using experimental data relevant to ex-vessel phase conditions. With the developed model, the prediction accuracy was improved substantially such that the maximum relative prediction error was approximately 25% while the existing methodology showed a 76% error. The developed methodology is expected to be applicable for flammability evaluation in chemical as well as NPP industries.