This study was performed to obtain high conversion efficiency of NH3 and minimize generation of nitrogen oxides using metal-supported catalyst with Ag : Cu ratio. Through structural analysis of the prepared catalyst with Ag : Cu ratio ((10-x)Ag–xCu (0≤ x ≤6)), it was confirmed that the specific surface area was decrease with increasing metal content. A prepared catalysts showed Type Ⅱ adsorption isotherms regardless of the ratio Ag : Cu of metal content, and crystalline phase of Ag2O, CuO and CuAl2O was observed by XRD analysis. In the low temperature(150∼200 ℃), a conversion efficiency of AC_10 recorded the highest(98%), whereas AC_5 (Ag : Cu = 5 : 5) also showed good conversion efficiency(93.8%). However, in the high temperature range, the amounts of by-products(NO, NO2) formed with AC_5 was lower than that of AC_10. From these results, It is concluded that AC_5 is more environmentally and economically suitable.

Researches on the elimination of sulfur and nitrogen oxides with catalysts and absorbents reported many problems related with elimination efficiency and complex devices. In this study, decomposition efficiency of harmful gases was investigated. It was found that the efficiency rate can be increased by moving the harmful gases together with SPCP reactor and the catalysis reactor. Calcium hydroxide(Ca(OH)2), CaO, and TiO2 were used as catalysts. Harmful air polluting gases such as SO2 were measured for the analysis of decomposition efficiency, power consumption, and voltage according to changes to the process variables including frequency, concentration, electrode material, thickness of electrode, number of electrode winding, and additives to obtain optimal process conditions and the highest decomposition efficiency. The standard sample was sulfur oxide(SO2). Harmful gases were eliminated by moving them through the plasma generated in the SPCP reactor and the Ca(OH)2 catalysis reactor. The elimination rate and products were analyzed with the gas analyzer (Ecom-AC,Germany), FT-IR(Nicolet, Magna-IR560), and GC-(Shimazu). The results of the experiment conducted to decompose and eliminate the harmful gas SO2with the Ca(OH)2 catalysis reactor and SPCP reactor show 96% decomposition efficiency at the frequency of 10 kHz. The conductivity of the standard gas increased at the frequencies higher than 20 kHz. There was a partial flow of current along the surface. As a result, the decomposition efficiency decreased. The decomposition efficiency of harmful gas SO2 by the Ca(OH)2 catalysis reactor and SPCP reactor was 96.0% under 300 ppm concentration, 10 kHz frequency, and decomposition power of 20 W. It was 4% higher than the application of the SPCP reactor alone. The highest decomposition efficiency, 98.0% was achieved at the concentration of 100 ppm.

With industrial development, energy demands continue to rise. Fossil fuels release more air pollutants to produce the same amount of energy compared with other types of fuel. The harmful exhaust gas exacerbated by the increasing uses of vehicles also makes a contribution to the worsening of air pollution. Thus there is a need for various processing methods and technologies to eliminate harmful gases such as sulfur oxides released into the air. Researches on the elimination of sulfur and nitrogen oxides with catalysts and absorbents reported many problems due to elimination efficiency and complex devices. In an attempt to supplement them, this study set out to increase the decomposition efficiency of harmful gases by moving them through the plasma generated in the SPCP reactor and the catalysis reactor specially designed and manufactured. The study used calcium hydroxide(Ca (OH)2),CaO,andTiO2 as catalysts. Harmful air polluting gases such as SO2 were measured for decomposition efficiency, power consumption, and voltage according to changes to the process variables including frequency, concentration, electrode material, thickness of electrode, number of electrode winding, and additives to obtain optimal process conditions and the highest decomposition efficiency. The standard sample was sulfur oxide(SO2). Harmful gases were eliminated by moving them through the plasma generated in the SPCP reactor and the Ca(OH)2 catalysis reactor. The elimination rate and products were analyzed with the gas analyzer (Ecom-AC,Germany), FT-IR(Nicolet, Magna-IR560), and GC-(Shimazu). The results of the experiment conducted to decompose and eliminate the harmful gas SO2with the Ca(OH)2 catalysis reactor and SPCP reactor show 96 decomposition efficiency at the frequency of 10kHz. The conductivity of the standard gas increased according to frequency at high voltage of 20 kHz or more. There was a partial flow of current along the surface. As a result, the decomposition efficiency decreased. The use of tungsten electrode resulted in the highest decomposition efficiency by the Ca(OH)2 catalysis reactor and SPCP reactor, and it was followed by the copper and aluminum electrode in the order. As for the impacts of thickness of electrode at electric discharge, the thicker the electrode was, the higher decomposition efficiency became. As for the number of electrode winding, the more it was wound, the higher decomposition efficiency became. The decomposition efficiency of harmful gas SO2 by the Ca(OH)2 catalysis reactor and SPCP reactor was 96.0% under the conditions of 300ppm concentration, 10kHz frequency, and decomposition power of 20W. It was higher than 92% when only the SPCP reactor was used. Decomposition efficiency was the highest at 98.0% when the concentration was 100ppm. As for the effects of additives to fit actual exhaust gases, the more methane (CH4) was added, the higher decomposition efficiency became over 99%. The higher the oxygen concentration was, the higher decomposition efficiency became, as well

We demonstrated size control of Au nanoparticles by heat treatment and their use as a catalyst for single-walled carbon nanotube (SWNTs) growth with narrow size distribution. We used uniformly sized Au nanoparticles from commercial Au colloid, and intentionally decreased their size through heat treatment at 800 oC under atmospheric Ar ambient. ST-cut quartz wafers were used as growth substrates to achieve parallel alignment of the SWNTs and to investigate the size relationship between Au nanoparticles and SWNTs. After the SWNTs were grown via chemical vapor deposition using methane gas, it was found that a high degree of horizontal alignment can be obtained when the particle density is low enough to produce individual SWNTs. The diameter of the Au nanoparticles gradually decreased from 3.8 to 2.9 nm, and the mean diameter of the SWNTs also changed from 1.6 to 1.2 nm for without and 60 min heat treatment, respectively. Raman results reconfirmed that the prolonged heat treatment of nanoparticles yields thinner tubes with narrower size distribution. This work demonstrated that heat treatment can be a straightforward and reliable method to control the size of catalytic nanoparticles and SWNT diameter.

피셔-트롭쉬 합성 반응은 촉매 표면에서 합성가스 (CO+H₂)를 탄화수소로 전환하는 반응이다. 코발트 또는 철계 촉매는 친환경적인 디젤 연료를 생산할 수 있고 합성가스의 전환율이 높은 촉매로 알려져 있다. 피셔-트롭쉬 반응에 사용되는 촉매의 활성은 촉매 표면에서의 활성점에 의존적이다. 활성점은 활성 물질의 크기, 담지량, 환원율, 지지체와 활성물질의 상호작용에 의해 결정된다. FT 촉매 제조 방법으로 활성물질의 크기를 조절하는 등의 새로운 방법들이 시도되고 있다. 여기에서는 촉매의 제조 방법과 환원 특성을 비롯한 촉매의 형태와 반응 조건을 포함한 반응기 형태에 대해 알아보겠다.

2010년 전국적으로 소, 돼지와 같은 동물에 구제역이 발병하였고, 이에 전국에 약 4,800여개의 매몰지가 긴급 조성되고 약 300만 마리의 동물들을 살처분 되었다. 이렇게 조성된 매몰지 내부에서는 가축사체가 부패하는 과정에서 황화수소, 메르캅탄류, 아민류 와 같은 악취물질이 생성되고, 매몰지 이설과정에서 대기 중으로 확산된다. 본 연구에서 는 가축 매몰지 이설과정 중에 발생하는 황 계열 물질을 저온 플라즈마 시스템을 적용하 여 저감하고자 하였다. 특히 플라즈마 시스템에서 상대습도에 따른 황화수소와 다이메틸 다이설파이드(DMDS) 제거량 변화를 실험적으로 확인하였다. 동일한 유입 조건에서 상대 습도가 증가함에 따라 황화수소와 DMDS의 제거율은 증가하였고, 이는 상대습도가 높아 지면서 발생하는 오존량이 증가하였기 때문이었다. 황화수소와 DMDS의 오존 반응식을 깁스 자유에너지로 비교해보면 DMDS의 오존 산화가 더 높은 에너지를 방출하는 것으로 나타나며, 이에 따라 황화수소보다는 DMDS가 먼저 오존에 의해 산화되며 남은 황화수 소는 촉매 층에서 추가 반응하는 것으로 판단된다.

In this study, the air pollutant removal such as sulfur oxides was studied. A combination of the plasma discharge in the reactor by the reaction surface discharge reactor Calcium hydroxides catalytic reactor and air pollutants, hazardous gas SOx, changes in gas concentration, change in frequency, the thickness of the electrode, kinds of electrodes and the addition of simulated composite catalyst composed of a variety of gases, including decomposition experiments were performed by varying the process parameters. The experimental results showed the removal efficiency of 98% in the decomposition of sulfur oxides removal experiment when Calcium hydroxides catalysts and the tungsten(W) electrodes were used. It was increased 3% more than if you do not have the catalytic. If added to methane gas was added the removal efficiency increased decomposition.

In this study, a combination of the plasma discharge in the reactor by the reaction surface discharge reactor complex catalytic reactor and air pollutants, hazardous gas SOx, change in frequency, residence time, and the thickness of the electrode, the addition of simulated composite catalyst composed of a variety of gases, including decomposition experiments were performed by varying the process parameters. 20W power consumption 10kHz frequency decomposition removal rate of 99% in the decomposition of sulfur oxides removal experiment that is attached to the titanium dioxide catalyst reactor experimental results than if you had more than 5% increase. If added to methane gas was added, the removal efficiency increased decomposition, the oxygen concentration increased with increasing degradation rate in the case of adding carbon dioxide decreased.

The objective of this study is to maintain the same frequency as the electrode material, concentration, duration of decomposition efficiency, power consumption and voltage measurements using a composite catalyst according to the change of process parameters to obtain the optimum state of the process and the maximum decomposition efficiency. In this paper, known as a major cause of air pollution, such as NO, NO2, SO2, frequency, flow rate, concentration, the material of the electrodes, and using TiO2 catalyst reactor with surface discharge caused by discharging the reactor plasma NOx, SOx decompose the harmful gas want to remove.

In this paper, a three dimensional numerical analysis tool was applied to study the PEMFC performance characteristics. The porosity and electrical conductivity of GDL and CL as well as the relative humidity of anode and cathode channel gas were selected as simulation parameters. As the porosity of GDL and CL increases, current density and temperature increase because reactant gases diffuse well. As the electrical conductivity of GDL and CL increases, current density and temperature increase due to increased electron transfer rate. As anode relative humidity increases, current density and temperature increase. Unlike anode, current density and temperature increase when cathode relative humidity increases from 0 percent to 60 percent. Then current density and temperature decrease when cathode relative humidity increases from 60 percent to 100 percent.

Co and Ni as catalysts in SnO2 sensors to improve the sensitivity for CH4 gas and CH3CH2CH3 gas were coated by a solution reduction method. SnO2 thick films were prepared by a screen-printing method onto Al2O3 substrates with an electrode. The sensing characteristics were investigated by measuring the electrical resistance of each sensor in a chamber. The structural properties of SnO2 with a rutile structure investigated by XRD showed a (110) dominant SnO2 peak. The particle size of the SnO2:Ni powders with Ni at 6 wt% was about 0.1 μm. The SnO2 particles were found to contain many pores according to a SEM analysis. The sensitivity of SnO2-based sensors was measured for 5 ppm of CH4 gas and CH3CH2CH3 gas at room temperature by comparing the resistance in air to that in the target gases. The results showed that the best sensitivity of SnO2:Ni and SnO2:Co sensors for CH4 gas and CH3CH2CH3 gas at room temperature was observed in SnO2:Ni sensors coated with 6 wt% Ni. The SnO2:Ni gas sensors showed good selectivity to CH4 gas. The response time and recovery time of the SnO2:Ni gas sensors for the CH4 and CH3CH2CH3 gases were 20 seconds and 9 seconds, respectively.

The sol-gel technique has been studied to fabricate a homogeneous Fe-Mo/MgO catalyst. Ambient effects (air, Ar, and H2) on thermal decomposition of the citrate precursor have been systematically investigated to fabricate an Fe-Mo/MgO catalyst. Severe agglomeration of metal catalyst was observed under thermal decomposition of citrate precursor in air atmosphere. Ar/H2 atmosphere effectively restricted agglomeration of bimetallic catalyst and formation of highly-dispersed Fe-Mo/MgO catalyst with high specific surface-area due to the formation of Fe-Mo nanoclusters within MgO support. High-quality thin-multiwalled carbon nanotubes (t-MWCNTs) with uniform diameters were achieved on a large scale by catalytic decomposition of methane over Fe-Mo/MgO catalyst prepared under Ar-atmosphere. The produced t-MWCNTs had outer diameters in the range of 4-8 nm (average diameter ~6.6 nm) and wall numbers in the range of 4-7 graphenes. The as-synthesized t-MWCNTs showed product yields over 450% relative to the utilized Fe-Mo/MgO catalyst, and indicated a purity of about 85%.

The objective of this study is to obtain the optimal process condition and the maximum decomposition efficiency by measuring the decomposition efficiency, electricity consumption, and voltage in accordance with the change of the process variables such as the frequency, maintaining time period, concentration, electrode material, thickness of the electrode, the number of windings of the electrode, and added materials etc. of the harmful atmospheric contamination gases such as NO, NO2, and SO2 etc. with the plasma which is generated by the discharging of the specially designed and manufactured TiO₂catalysis reactor and SPCP reactor.

Electricity is generated by the combined reactions of hydrogen oxidation and oxygen reduction which occur on the Pt/C catalyst surface. There have been lots of researches to make high performance catalysts which can reduce Pt utilization. However, most of catalysts are synthesized by wet-processes and a significant amount of chemicals are emitted during Pt/C synthesis. In this study, Pt/C catalyst was produced by arc plasma deposition process in which Pt nano-particles are directly deposited on carbon black surfaces. During the process, islands of Pt nano-particles were produced and they were very fine and well-distributed on carbon black surface. Compared with a commercialized Pt/C catalyst (Johnson & Matthey), finer particle size, narrower size distribution, and uniform distribution of APD Pt/C resulted in higher electrochemical active surface area even at the less Pt content.

One of main catalysts for De-NOx in SCR is a V2O5/TiO2, and this work formulated powdery catalysts focusing ultimately on corrugate catalytic support. The prepared catalyst consisted of anatase TiO2. Amount of the added vanadium oxide determined the viscosity of catalyst slurry, which is important for washcoat for a final corrugate type catalytic reactor. The test showed a proportional relation between adsorption amount of ammonia and specific surface area. De-NOx efficiency could be obtained up to 96.3 % at 400℃ with a spacial velocity of 4,000hr-1.

On cold start operation of an SI engine, a catalyst shows poor performance before it reaches activation temperature. Therefore, fast warmup of the catalyst is very crucial to reduce harmful emissions. In this study, an appropriate control strategy is investigated to increase exhaust gas temperature through changes of spark timing. Combustion stability is also considered at the same time. Exhaust gas temperature and pressure of combustion chamber are measured to investigate the effects of spark timings on cold start and idle performance. Experiments showed that retarded spark timing promotes the combustion at the end of expansion stroke and increases exhaust gas temperature during cold start.

In the present study, potassium and caesium doped Ag/ catalysts were synthesized by simple wet impregnation method and evaluated for selective catalytic reduction (SCR) of NOx using methane. TEM analysis and diffraction patterns demonstrated the finely dispersed Ag particles. BET surface measurements reveal that the prepared materials have moderate to high surface area and the metal amount found from ICP analysis was well matching with the theoretical loadings. The synthesized K-Ag/ and Cs-Ag/ catalysts exhibited a promotional effect on deNOx activity in the presence of and . The long-term isothermal studies at under oxygen rich condition showed the superior catalytic properties of the both alkali promoted samples. The crucial catalytic properties of materials are attributed to NO adsorption properties detected by the NO TPD.

In this study, the used DOCs, which could remove the air pollutants such as CO and HC in the exhaust gas from diesel vehicle, were remanufactured by various conditions. Their catalytic performances and characterization were also investigated. The remanufacturing process of the deactivated DOCs includes high temperature cleaning of incineration, ultrasonic cleaning for washing with acid/base solutions to remove deactivating materials deposited to the surface of the catalysts, and active component reimpregnation for reactivating catalytic activity of them. The catalytic performance tests of the remanufactured DOCs were carried out by the diesel engine dynamo systems and chassi dynamo systems in CVS-75 mode. All prepared catalysts were characterized by the optical microscopes, SEM, EDX, porosimeter and BET to investigate correlations between catalytic reactivity and surface characteristics of them. The remanufactured DOCs at various conditions showed the improved catalytic performances reaching to 90% of fresh DOC, which is attributed to remove the deactivating materials from the surface of the used DOC through the analysis of catalytic performance test and their characterization.

The analysis of reaction kinetics provided that the reaction order was the 1st of triglyceride and the rate constant was 0.067 min-1. The transesterification of camelina oil using 0.6 wt% mixed catalyst which consists of 40 v/v% of potassium hydroxide (1 wt%) and 60 v/v% of tetra methyl ammonium hydroxide (0.8 wt%), was carried out at 65℃ on the tubular reactor packed with static mixer. The conversion was shown to be 95.5% at the 6:1 molar ratio of methanol to oil, flow rate of feed of 3.0 mL/min and 24 of element of static mixer. The volume of washing water emitted by 0.6 wt% mixed catalyst was the half of the volume emitted by 1 wt% potassium hydroxide.

It has been stand high in estimation to converse from Carbon dioxide to Dimethyl Ether in new alternative fuel energy division in 21C, especially Using of DME in point of view of transportation fuel has been discussed of a new clean energy which is very lower of exhaust gas than gasoline and diesel energy. In this paper it is used ZSM-5 and I developed new catalyst by addition of cerium to control acidity. The new catalyst was proved high conversion rate, when it was conversed from methanol to DME, there wasn't any additional material except DME and water, and I overlooked reaction temperature, reaction time, amount of catalyst, amount of added cerium, effect of water content in methanol, reaction temperature by making change of reaction time. I have conclude that conversion rate to DME was increased as increased of catalyst amounts. The best catalyst condition of without additional product was treated poisoning from ZSM-5 to 5% cerium and new catalyst was not effected in purity of fuel methanol.