• Title/Summary/Keyword: chemical reaction.

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고체/기체계 가역 화학 반응열 이용 HEAT PUMP 기술 개발

  • 이종호
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1993.11a
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    • pp.78-81
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    • 1993
  • AN EXTENSIVE RESEARCH AND DEVELOPMENT WORK WILL BE CARRIED OUT FOR THE COMMERCIALIZATION OF THE CHEMICAL HEAT PUMP SYSTEM WHICH BASED ON THE ELF AQUITAINE FRANCE PATENTED AND KIME LICENSED SOLID/GAS CHEMICAL REACTION TECHNOLOGY. TOWARD ON THAT GOAL, THE BASIC AND ENGINEERING DETAILS SUCH AS IMPEX BLOCK MATERIAL, PHYSICO-CHEMICAL AND THERMO-CHEMICAL CHARACTERISTICS OF REACTION MECHANISMS IN THE SOLID/GAS CHEMICAL REACTION HEAT PUMP SYSTEMS. THREE KIND OF APPLICATION SYSTEM ARE NOW INVESTIGATED; AIR CONDITIONING, REFRIGERATOR AND INDUSTRIAL PROCESS HEATING AND COOLING SYSTEM.

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Effect of added mesophase pitch during the pitch synthesis reaction of PFO

  • Kim, Ji Hong;Kim, Jong Gu;Lee, Chul Wee;Lee, Ki Bong;Im, Ji Sun
    • Carbon letters
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    • v.23
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    • pp.48-54
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    • 2017
  • This research considers the effect of added mesophase pitch (MP) as an additive during the pitch synthesis reaction of pyrolyzed fuel oil (PFO). Two effects are generated by adding MP. One is an enhancement of thermal stability due to the high thermal property of the additive; the other is that the volatile compounds that were removed by vaporization of PFO during the thermal reaction can participate in the pitch synthesis reaction ($PFO{\rightarrow}pitch$) more efficiently. The effect differs according to the amount of the additive. When the amount of the additive is less than 7 wt%, the first effect is dominant, whereas the second effect is dominant when the additive amount exceeds 10 wt%.

Characteristics and Kinetics of the Addition Reaction of Resol Resin Formation (레졸수지 합성에서 부가반응 특성 및 반응속도론)

  • Ann, Jae-Ok;Nam, Young-Woo
    • Korean Chemical Engineering Research
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    • v.46 no.2
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    • pp.301-309
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    • 2008
  • In this study, the effect of formaldehyde to phenol (F/P) molar ratios, catalyst wt%, and reaction temperature on the chemical structure was studied utilizing a two-level full factorial experimental design. The effect of three variables on the chemical structure was analyzed by using three-way ANOVA of SPSS. Concentration of methyrol-substituted phenols after 300 min addition reaction increased with higher the F/P mole ratio, lower the reaction temperature and lower the catalyst wt%. Resol catalysed by barium hydroxide showed higher addition of formaldehyde onto ortho positions of phenolic rings. A simplified elementary reaction model for resole type phenolic resin formation which do not consider the dissociation of phenolic compounds and the fraction of formaldehyde in the form of methylene glycol was proposed and compared with Zavitsas' type models. Elementary reaction model showed error of 2.79% compared to the error of 3.27% in Zavitsas' type models. It was thought that the elementary reaction model could be used to predict the behavior of addition reaction in resol formation.

Photochemical Synthesis of Aspartylphenylalanyl Methyl Ester (광 알킬화 반응에 의한 Aspartylphenylalanyl Methyl Ester의 합성)

  • Sang Chul Shim;Kyu Ho Chae
    • Journal of the Korean Chemical Society
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    • v.19 no.5
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    • pp.367-374
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    • 1975
  • Glycine residue in N-X-glycylphenylalanine methyl ester(X = trifluoroacetyl or acetyl) was converted into aspartic acid derivative by a photoalkylation reaction. The reaction was induced with 350 nm lamp using a combination of diacetyl/di-t-butyl peroxide (DBP) as the photoinitiator, and acetic anhydride as the alkylating agent. In the thermal reaction with DBP and acetic anhydride, the same alkylation reaction of the dipeptide was observed. From this thermal alkylation reaction the photoalkylation reaction is also thought to undergo via free radical mechanism.

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Kinetics and Optimization of Dimethyl Carbonate Synthesis by Transesterification using Design of Experiment

  • Lee, Kilwoo;Yoo, Kye Sang
    • Korean Chemical Engineering Research
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    • v.56 no.3
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    • pp.416-420
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    • 2018
  • A comprehensive kinetic study has been conducted on dimethyl carbonate synthesis by transesterification reaction of ethylene carbonate with methanol. An alkali base metal (KOH) was used as catalyst in the synthesis of DMC, and its catalytic ability was investigated in terms of kinetics. The experiment was performed in a batch reactor at atmospheric pressure. The reaction orders, the activation energy and the rate constants were determined for both forward and backward reactions. The reaction order for forward and backward reactions was 0.87 and 2.15, and the activation energy was 12.73 and 29.28 kJ/mol, respectively. Using the general factor analysis in the design of experiments, we analyzed the main effects and interactions according to the MeOH/EC, reaction temperature and KOH concentration. DMC yield with various reaction conditions was presented for all ranges using surface and contour plot. Furthermore, the optimal conditions for DMC yield were determined using response surface method.

Studies on the Bleaching of Rice-Straw chemical Pulp(I) (볏짚화학펄프의 표백에 관한 연구)

  • 강진하;박성종
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.32 no.3
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    • pp.65-74
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    • 2000
  • This study was carried out to acquire basic data necessary for the use of rice-straw chemical pulp. It investigated the proper bleaching conditions when rice-straw chemical pulps(alkaline sulfite-Na2S2O4 pulp) were bleached with the various kinds of bleaching agents. And physical properties of bleached pulps were tested. The results of this study were as follows; 1, The proper conditions of chlorine sequence were determined to be 4% concentration of chlorine 25$^{\circ}C$ of reaction temperature and 50 minutes of reaction time. 2. For calcium hypochlorite sequence the proper conditions of chemical concentration reac-tion temperature and reaction time were 3% 25$^{\circ}C$ and 20 minutes respectively. 3. For chlorine dioxide sequence the proper conditions were 1% concentration of chlorine dioxide 70$^{\circ}C$ of reaction temperature and 2hr. of reaction time. 4. The proper conditions of hydrogen peroxide sequence were 1.5% concentration of hydro-gen peroxide 70$^{\circ}C$ of reaction temperature and 1hr. of reaction time respectively. 5. When the rice-straw chemical pulp were bleached with four kinds of bleaching agents methioned above in the proper conditions respectively brightnesses were the order of chlorine dioxide calcium hypochlorite, chlorine, hydrogen peroxide. And strengthes of pulps bleached with chlorine dioxide and hydrogen peroxide were higher than those of pulps bleached with other bleaching agents.

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A Spectroscopic Study on Singlet Oxygen Production from Different Reaction Paths Using Solid Inorganic Peroxides as Starting Materials

  • Li, Qingwei;Chen, Fang;Zhao, Weili;Xu, Mingxiu;Fang, Benjie;Zhang, Yuelong;Duo, Liping;Jin, Yuqi;Sang, Fengting
    • Bulletin of the Korean Chemical Society
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    • v.28 no.10
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    • pp.1656-1660
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    • 2007
  • Using solid inorganic peroxides (including Li2O2, Na2O2, SrO2 and BaO2) as starting materials, three reaction paths for singlet oxygen (1O2) production were developed and studied. Their 1O2 emission spectra in the near- IR region and visible region from these reaction paths were simultaneously recorded by a near-IR sensitive Optical Multichannel Analyzer and a visible sensitive Optical Spectrum Analyzer, respectively. The comparison of their 1O2 emission spectra indicated that: (1) in term of the efficiency for 1O2 production, the gasliquid- solid reaction path (in which Cl2 or HCl and H2O reacted with the solid inorganic peroxides suspension in CCl4) was prior to the gas-solid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides suspension in CCl4), but was inferior to the gas-liquid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides solution in H2O or D2O); (2) the alkali metal peroxides (such as Li2O2 and Na2O2) was prior to the alkaline earth metal peroxides (such as SrO2 and BaO2) as the solid reactants, and Cl2 was favorable than HCl as the gas reactant in efficiency for 1O2 production in these reaction paths.