• Title/Summary/Keyword: reaction gas

Search Result 2,909, Processing Time 0.036 seconds

ELECTROMAGNETIC MEANING OF GIBB'S FREE ENERGY, ELECTOLYSIS, CELL REACTION AND BROWN GAS

  • Oh, Hung-Kuk
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
    • /
    • 2001.05a
    • /
    • pp.10-14
    • /
    • 2001
  • Physical chemistry states that electric potential is due to Gibb's free energy from chemical reaction of the electric cell. However we have not the electromagnetic meaning of Gibb's free energy. the free energy is discovered to be a kinetic energy part of the rotating electromagnetic wave ($\pi$-ray), which is different from conventional Coulomb attraction energy and can anticipate that there is a current difference between before and after the electric load. This paper manipulates the relationship between $\pi$-rays (Gibb's free energy) and electrolysis, cell reaction and brown gas reaction.

  • PDF

Precipitation of Manganese in the p-Xylene Oxidation with Oxygen-Enriched Gas in Liquid Phase

  • Jhung, Sung-Hwa;Park, Youn-Seok
    • Bulletin of the Korean Chemical Society
    • /
    • v.23 no.3
    • /
    • pp.369-373
    • /
    • 2002
  • The liquid phase oxidation of p-xylene has been carried out with oxygen-enriched gas, and the manganese component was precipitated probably via over-oxidation to $Mn^{4+}$. The precipitation increased with rising oxygen concentration in the reaction gas and occurred mainly in the later part of the oxidation. The activity of the reaction decreased, and the blackening of the product and side reactions to carbon dioxide increased with the degree of precipitation. Precipitation can be decreased with the addition of metal ions, such as cerium, chromium and iron.

Density Functional Theory Study of Competitive Reaction Pathways of Ti+ with Fluorinated Acetone in the Gas Phase

  • Hong, Ki-Ryong;Kim, Tae-Kyu
    • Journal of the Korean Chemical Society
    • /
    • v.56 no.1
    • /
    • pp.14-19
    • /
    • 2012
  • We investigate the doublet and quartet potential energy surfaces associated with the gas-phase reaction between $Ti^+$ and $CF_3COCH_3$ for two plausible reaction pathways, $TiF_2^+$ and $TiO^+$ formation pathways by using the density functional theory (DFT) method. The molecular structures of intermediates and transition states involved in these reaction pathways are optimized at the DFT level by using the PBE0 functional. All transition states are identified by using the intrinsic reaction coordinate (IRC) method, and the resulting reaction coordinates describe how $Ti^+$ activates $CF_3COCH_3$ and produces $TiF_2^+$ and $TiO^+$ as products. On the basis of presented results, we propose the most favorable reaction pathway in the reaction between $Ti^+$ and $CF_3COCH_3$.

A Study of Nitrous Oxide Thermal Decomposition and Reaction Rate in High Temperature Inert Gas (고온 불활성 기체 분위기에서 아산화질소 열분해 및 반응속도에 관한 연구)

  • Lee, Han Min;Yun, Jae Geun;Hong, Jung Goo
    • Journal of ILASS-Korea
    • /
    • v.25 no.3
    • /
    • pp.132-138
    • /
    • 2020
  • N2O is hazardous atmosphere pollution matter which can damage the ozone layer and cause green house effect. There are many other nitrogen oxide emission control but N2O has no its particular method. Preventing further environmental pollution and global warming, it is essential to control N2O emission from industrial machines. In this study, the thermal decomposition experiment of N2O gas mixture is conducted by using cylindrical reactor to figure out N2O reduction and NO formation. And CHEMKIN calculation is conducted to figure out reaction rate and mechanism. Residence time of the N2O gas in the reactor is set as experimental variable to imitate real SNCR system. As a result, most of the nitrogen components are converted into N2. Reaction rate of the N2O gas decreases with N2O emitted concentration. At 800℃ and 900℃, N2O reduction variance and NO concentration are increased with residence time and temperature. However, at 1000℃, N2O reduction variance and NO concentration are deceased in 40s due to forward reaction rate diminished and reverse reaction rate appeared.

Etching Reaction of $UO_2\;with\;CF_4/O_2$ Mixture Gas Plasma

  • Kim, Yongsoo;Jinyoung Min;Kikwang Bae;Myungseung Yang
    • Nuclear Engineering and Technology
    • /
    • v.31 no.2
    • /
    • pp.133-138
    • /
    • 1999
  • Research on the etching reaction of UO$_2$ with CF$_4$/O$_2$gas mixture plasma is carried out. The reaction rates are investigated as a function of CF$_4$/O$_2$ ratio, plasma power, and substrate temperature. It is found that there exists an optimum CF$_4$/O$_2$ ratio around 4:1 at all temperatures up to 37$0^{\circ}C$ and surface analysis using XPS X-ray Photoelectron Spectroscopy) confirms the result. Peak rate at the optimum gas composition increases with increasing temperature. Highest rate obtained in this study leaches 1050 monolayers/min. at 37$0^{\circ}C$ under r. f. power of 150 W, which is equivalent to about 0.5${\mu}{\textrm}{m}$/min. The rate also increases with increasing r. f. power, thus, higher power and higher substrate temperature will undoubtedly raise the etching reaction rate much further. This reaction seems to be an activated process, whose activation energy will be derived in the following experiments.

  • PDF

Growth and Resistance Properties of Carbon Nanowall According to the Variation of Reaction Gas (반응가스의 변화에 따른 탄소나노월의 성장 및 저항 특성)

  • Kim, Sung Yun;Lee, Sangjoon;Choi, Won Seok;Joung, Yeun-Ho;Lim, Dong-Gun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.27 no.4
    • /
    • pp.217-220
    • /
    • 2014
  • Graphite electrodes are used for secondary batteries, fuel cells, and super capacitors. Research is underway to increase the reaction area of graphite electrodes. In this study, we have investigated the growth properties of carbon nanowall (CNW) according to the ingredient of gas. Microwave plasma enhanced chemical vapor deposition (MPECVD) system was used to grow CNW on Si substrate with a variety of the reaction gas. The planar and vertical growth conditions of the grown CNWs according to the ingredient of the gas were characterized by a field emission scanning electron microscopy (FE-SEM) and energy dispersive spectroscopy (EDS). The electrical characteristics of CNWs were analyzed using a 4-point probe.

Effects of Magnetite added with Metallic Oxide on the Decomposition Reaction of Carbon Dioxide (CO$_2$ 분해 반응에서 금속 산화물이 첨가된 $Fe_2O_4$의 영향)

  • Kim, Seung-Ho;Park, Young-Goo
    • Journal of Environmental Health Sciences
    • /
    • v.24 no.1
    • /
    • pp.32-37
    • /
    • 1998
  • The Carbon Dioxide is the gas, which causes green house effects, unusual changes in the weather, destruction of the life. Almost every nation in the world is trying to search the countermeasure to this poisonous gas. I synthesized $Fe_3O_4$ and NaOH, in order to decompose the Carbon Dioxide. Among the particles synthesizing $Fe_3O_4$, I chose the equivalent ratio 1.00 which can decompose the Carbon Dioxide best, and fixed that equivalent ratio and added the 0.005-3.00 mole percentage of NiCl$_2$ and synthesized $Fe_3O_4$. I studied the decomposition of the Carbon Dioxide and methanized reaction, by measuring its crystal structure, thermochemistrical character and specific surface area. In decomposing the Carbon Dioxide, I used oxygen-deficit Magnetite which I produced by injecting the hydrogen gas into the synthesized sample. I observed the methanization reaction by raising the temperature of sample up to 650$\circ$C and having it reacted with the hydrogen gas. The decomposition of the Carbon Dioxide was added 0.005, 0.03, 0.05 mole percentage of NiCl$_2$ was more effective than pure $Fe_3O_4$. All sample in which the decomposition of the Carbon Dioxide took place produced the methane gas.

  • PDF

A Design for Natural Gas Reforming Reactor (천연가스 개질기 설계)

  • Lee, Taeckhong;Choi, Woonsun
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.23 no.5
    • /
    • pp.545-550
    • /
    • 2012
  • This work is for the design study of natural gas reformer (40 $m^3/hr$ over). We used experimental kinetic data from literature. After that, we set up theoretical model based on experimental reaction kinetic data. The shape of reactor is 1.7 m long and 200 mm dia. with cylinder geometry. Volume of reactor is 53.4 liter. Average flow velocity of gases in the reactor has been determined 0.272 m/sec and residence time is 9.26 sec. Reaction temperature is $850^{\circ}C$, with pressure 9.3 Bar. Used natural gas volume is about 9.21 $m^3/hr$. Produced hydrogen is 43.7 $m^3/hr$ with no change of pressure. Unreacted natural gas is 0.09 $m^3/hr$ and the amount of steam is 26.9 $m^3/hr$. Steam to $CH_4$ (s/c ratio) is 2.91. Reforming reaction take place from the reactor entrance to 120 cm region of cylinder type reactor. After the entrance of reacting gases to 120 cm region, the reaction reaches equilibrium which is close to products. This study can be applicable to design various reactors. Output data is in good agreements with the data in literatures1).

A simulation study on synthesis gas process optimization for GTL (Gas-to-Liquid) pilot plant (GTL 합성유 제조용 파일럿 플랜트 최적 운전 변수 도출을 위한 합성가스 공정 시뮬레이션 연구)

  • Kim, Yong Heon;Bae, Ji Han;Park, Myoung Ho
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2011.05a
    • /
    • pp.74.2-74.2
    • /
    • 2011
  • A simulation study on synthesis gas process in GTL process was carried out in order to find optimum operation conditions for GTL (gas-to-liquid) pilot plant design. Optimum operating conditions for synthesis gas process were determined by changing reaction variables such as feed temperature and pressure. During the simulation, overall synthesis process was assumed to proceed under steady-state conditions. It was also assumed that physical properties of reaction medium were governed by RKS (Redlich-Kwong-Soave) equation. The effect of temperature and pressure on synthesis gas process $H_2$/CO ratio were mainly examined. Simulation results were also compared to experimental results to confirm the reliability of simulation model. Simulation results were reasonably well matched with experimental results.

  • PDF

A Study on the Removal Reaction Characteristics of Sulfur Dioxide (대기오염 물질인 $SO_2$ 제거반응 특성 연구)

  • 강순국;정명규
    • Journal of Environmental Science International
    • /
    • v.4 no.1
    • /
    • pp.41-52
    • /
    • 1995
  • The effects of reaction temperature, SO2 and CO2 concentration in an air gas stream, particle sizes of limestone on the reactivity and capacity of SO2 removal have been determined in a thermogravimetric analyser(TGA). The apparent reaction order of sulfation reaction of pre-calcined lime(CaO) with respect to SO2 is found to be close to unity. The apparent activation energies are found to be 17,000 kcal/kmol for sulfation of pre-calcined lime and 19,500 kcal/kmol for direct sulfation of limestone(CaCO3). The initial sulfation reaction rate of pre-calcined lime increases with increasing temperature, whereas the sulfur capture capacity exhibits a maximum value at 90$0^{\circ}C$. In direct sulfation of limestone, sulfation reactivity and sulfur capature capacity of sorbent increase with increasing temperature and decreasing CO2 concentration in a gas bulk stream. The main pare of pre-calcined lime is shifted to the larger pore sizes and pore volume decreases with increasing sulfation time and temperature. The surface area of lime decreases with increasing calcination temperature under an air atmosphere, whereas is yearly constant under a CO2(5, 10%) atmosphere in a gas stream.

  • PDF