• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.347-347
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• 2010

We designed a new experimental set-up for measuring activity of heterogeneously catalyzed reactions. Using this set-up, we studied reduction of carbon dioxide by carbon dioxide reforming of methane (CRM) using nickel powder as catalyst. The properties of the catalysts were characterized by X-ray diffraction (XRD), Brunauer, Emmett & Teller (BET) surface area and X-ray photoelectron spectroscopy (XPS) techniques. The reactivity experiments were performed in the temperature range of $300\;-\;500^{\circ}C$. At reactivity experiment, result showed consumption of $CO_2$ and $CH_4$ with a 1:1 stoichiometry. At the same time, carbon monoxide and hydrogen were produced, which could be used for synthesizing fuels such as methanol. During the reaction, deposition of carbon on Ni was observed, which caused deactivation of the catalyst.

• Nuclear Engineering and Technology
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• v.45 no.2
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• pp.211-218
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• 2013

Large quantities of irradiated graphite waste from graphite-moderated nuclear reactors exist and are expected to increase in the case of High Temperature Reactor (HTR) deployment [1,2]. This situation indicates the need for a graphite waste management strategy. Of greatest concern for long-term disposal of irradiated graphite is carbon-14 ($^{14}C$), with a half-life of 5730 years. Fachinger et al. [2] have demonstrated that thermal treatment of irradiated graphite removes a significant fraction of the $^{14}C$, which tends to be concentrated on the graphite surface. During thermal treatment, graphite surface carbon atoms interact with naturally adsorbed oxygen complexes to create $CO_x$ gases, i.e. "gasify" graphite. The effectiveness of this process is highly dependent on the availability of adsorbed oxygen compounds. The quantity and form of adsorbed oxygen complexes in pre- and post-irradiated graphite were studied using Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) and Xray Photoelectron Spectroscopy (XPS) in an effort to better understand the gasification process and to apply that understanding to process optimization. Adsorbed oxygen fragments were detected on both irradiated and unirradiated graphite; however, carbon-oxygen bonds were identified only on the irradiated material. This difference is likely due to a large number of carbon active sites associated with the higher lattice disorder resulting from irradiation. Results of XPS analysis also indicated the potential bonding structures of the oxygen fragments removed during surface impingement. Ester- and carboxyl-like structures were predominant among the identified oxygen-containing fragments. The indicated structures are consistent with those characterized by Fanning and Vannice [3] and later incorporated into an oxidation kinetics model by El-Genk and Tournier [4]. Based on the predicted desorption mechanisms of carbon oxides from the identified compounds, it is expected that a majority of the graphite should gasify as carbon monoxide (CO) rather than carbon dioxide ($CO_2$). Therefore, to optimize the efficiency of thermal treatment the graphite should be heated to temperatures above the surface decomposition temperature increasing the evolution of CO [4].

• Korean Chemical Engineering Research
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• v.50 no.5
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• pp.908-912
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• 2012

Lauan sawdust was gasified by steam reforming for hydrogen production from biomass waste. The fixed bed gasification reactor with 1m height and 10.2 cm diameter was utilized for the analysis of temperature and catalysts effect. Steam was injected to the gasification reactor for the steam reforming effect. Lauan sawdust was mixed with potassium carbonate, sodium carbonate, calcium carbonate, sodium carbonate + potassium carbonate and magnesium carbonate + calcium carbonate catalysts of constant mass fraction of 8:2 which was injected to the fixed gasification equipment. The compositions of production gas of gasification reaction were analyzed at the temperature range from $400^{\circ}C$ to $700^{\circ}C$. Fractions of hydrogen, methane and carbon monoxide gas in the production gas increased when catalysts were used. Fractions of hydrogen, methane and carbon monoxide gas were increased with increasing temperature. The highest hydrogen yield was obtained with sodium carbonate catalyst.

• Journal of Preventive Medicine and Public Health
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• v.5 no.1
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• pp.17-23
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• 1972

Carbon Monoxide poisoning is one of the most serious Public health problems in Korea. The incidence rate. officially reported has been known to be the highest in the world. This high incidence is mainly due to the wide prevalence of anthracite coal briquette as the domestic fuel for unique Korean heating system called 'ondol,' The coal briquette gas contains around 3-5% of Carbon Monoxide. A nation-wide effort to eliminate or reduce this serious hazards has produced little effect and the most hospitals are offering very ineffective measures such as oxygen inhalation through nasal catheter. Author has believed that this preventable accident should be approached by the secondary preventive measure because of our socio-economic status do not allow us optimistic results from primary preventive measure as far as the problem of CO poisoning is concerned. Author has treated 466 patients during 30 months period by Hyperbaric Oxygenation at Seoul National University Hospital. The results found are as follows. 1. Female has a higher incidence rate than male and the age group between 15-29 years showed highest incidence. 2. The recovery time depends on the time when the patients arrived at hospital. Earlier the arrival time, shorter the recovery time. 3. Some objective signs are representing typical physiological response to tissue hypoxia. 4. Therapeutic effectiveness of Hyperbaric Oxypenation is confirmed by such indices as recovery rate, Admission rate and average stay in hospital. Futher, these results are cocordant with other reports on the clinical value of Hyperbaric Oxygenation in the treatment of CO poisoning.

• Journal of the Korean Society of Safety
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• v.5 no.2
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• pp.32-39
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• 1990

The ${\gamma}$-Fe$_2$O$_3$ compounds were oxidized in the furance after gas detecting sensor made molding as the Fe$_3$O$_4$ the synthesized Fe$_3$O$_4$, by ferrous sulfate and sodium hydroxide. Their sensities on carbon monoxide, ethyl alcohol and L. P. G. were measured at various temperatures, respectively. And then their electrical resistivities, thermal properties (D.T.A. ＆ T.G.A.), were examined about their having an effet on the gas-sensing in company with the effect of pure ${\gamma}$-Fe$_2$O$_3$ and the detecting sensor ${\gamma}$-Fe$_2$O$_3$, which reacts with $K_2$CO$_3$ in the hydrothermal coundition, and the electrical conductive mechanism was reflected simultaneously. It was observed that the electrical conductivities and response ratios showed highest value at the endothermic temperature part, 300~35$0^{\circ}C$ of D.T.A.―curve. Consequently, the response ratios and response times of the hydrothermal detecting sensor were higher than that of pure detecting sensor, the specific surface areas were the highest at the endothermic range of D.T.A.-curve. These response ratios of detecting sensor for $K_2$CO$_3$, process at hydrothermal condition on carbon monoxide appeared higher than that on ethyl alcohol and in case of L.P.G. last.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.4002-4006
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• 2014

The automotive exhaust gases generated by the vehicles containing carbon monoxide, hydrocarbons and lead, is a large concern because of their harm to human health or the living environment. To reduce exhaust gas, it is important to develop a variety of techniques that are currently being used by elemental analysis to determine the optimal conditions. In this study, the anti-freeze coolant contained in the exhaust gas was examined, which can affect the emissions. The effects of the commercially available coolant from five domestic companies on the HC, NOx and $CO_2$ emissions were analyzed to determine the optimal amount of antifreeze. In addition, antifreeze products from the five companies were analyzed with respect to driving time of the cooling fan and the correlation of the NOx emission analysis. The temperature of the engine oil was matched using a manual gear of small passenger inspection standard speed $40{\pm}2Km/h$ so the vehicle could meet the specifications for inspection $90{\sim}93^{\circ}C$. The Company D fan operation time resulted in the shortest antifreeze, $CO_2$ and NOx emissions.

• Analytical Science and Technology
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• v.13 no.2
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• pp.222-228
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• 2000

A detector for monitoring carbon monoxide (CO) in ambient air by nondispersive infrared (NDIR) spectroscopy has been developed and investigated its sensitivity and stability. The essential parts of the absorption cell are three spherical concave mirrors so as to improve the sensitivity by increasing the light path length in the cell. The radius and center of curvature of mirrors and position in the cell was calculated by computer simulation in order that the light path length may be 16m into the 50cm cell. The number of traversals and optical path properties were confirmed by laser beam alignment in transparent absorption cell. The photoconductive type lead selenide (PbSe) was used as CO sensing material, which was cooled to increase the responsibility by thermoelectric cooling method. The detection limit and span drift of the developed CO detector was 0.24ppm and 0.03ppm(v/v) respectively.

• Korean Journal of Microbiology
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• v.21 no.1
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• pp.27-35
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• 1983

The stoichiometry between the consumption of CO and $O_2$ and the production of $CO_2(2CO+O_2{\rightarrow}2CO_2)$) showed that Pseudomonas carboxydohydrogena grows as a typical aerobic CO oxidizer with CO. The optimal concentration of CO for growth was found to be 30% in gas mixture with air. The initial buffer concentration of the culture medium did not affect the growth of this bacterium. P. carboxydohydrogena is an obligate aerobe and dose not use nitrate as a terminal electron acceptor. The CO dehydrogenase is an inducible and soluble enzyme. The reaction rate and stability were maximal at pH7.5, and the Arrhenius plot revealed an activation energy of 37.7kJ/mol (9.0 Kcal/mol). The crude enzyme used methylene blue, thionin, and toluylene blue as electron acceptors for the oxidation of CO to $Co_2$ under anaerobic conditions. It was found that water must be the source of the second oxygen atom for CO oxidation.

• Journal of Hydrogen and New Energy
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• v.27 no.6
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• pp.628-635
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• 2016

Natural gas reformed hydrogen is used as a fuel of fuel cell vehicle, PSA process is used for the purification of reformed hydrogen. In this study, the performance of CO adsorbent in PSA process was evaluated. Zeolite adsorbents used in the commercial PSA process is used. The physical and chemical properties of adsorbents were characterized using BET apparatus, XRD, and FE-SEM. The breakthrough apparatus modified from GC was used for the CO breakthrough experiment, the quantitative analysis of CO adsorption capacity was performed using CO breakthrough curve. Zeolite 10X and 13X showed superior CO adsorption capacity than activated alumina. The CO adsorption capacity of zeolite 10X is more than twice of zeolite 13X even the BET surface area is low. It seems that the presence of $Ca^{2+}$ cation in zeolite 10X is beneficial to the adsorption of CO.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.1
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• pp.83-86
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• 2004

A high temperature tolerant microelectronic-based carbon monioxde(CO) gas sensor has been developed. The gas sensing performance has been studied over a wide temperature range$(100-300^\circ{C)}$. The gas sensitivity of the sensor is high, its initial sensing behavior is very fast, and the sensor is reproducible. Pt-SiC and $Pt-SnO_2-SiC$ diodes are fabricated using standard semiconductor processes and their CO gas-sensing behaviors are analyzed as a function of CO gas concentration and temperature by I-V and $\Delta{I-t}$ methods under steady-state and transient conditions. The sensitivity of the device with $Pt-SnO_2$ catalytic gate is higher than that of the Pt gate. The experimental results indicate that $SnO_2$ layer improves the catalytic reaction of the Pt layer.