Reaction pathway and kinetics for uncatalyzed partial oxidation of p-xylene in sub- and supercritical water

被引:37
作者
Kim, YL
Kim, JD
Lim, JS
Lee, YW
Yi, SC
机构
[1] Korea Inst Sci & Technol, Supercrit Fluids Res Lab, Seoul 130650, South Korea
[2] Hanyang Univ, Dept Chem Engn, Sungdong Gu, Seoul 133791, South Korea
关键词
D O I
10.1021/ie010952t
中图分类号
TQ [化学工业];
学科分类号
0817 ;
摘要
In sub- and supercritical water, partial oxidation of p-xylene was performed by the batch reactor without a catalyst at the conditions of 240-400 degreesC and 220-300 bar. The loaded amount of hydrogen peroxide was set to 21-100% of the stoichiometric requirements for oxygen. Conversion of p-xylene was reached over about 89.02% (in subcritical conditions) and over 99% (in supercritical conditions) within 20 min. In sub- and supercritical water, we proposed a simplified reaction pathway in parallel and the possible reaction mechanism from major products that consist of p-tolualdehyde, p-toluic acid, terephthalic acid, 4-carboxybenzaldehyde, toluene, and benzaldehyde. The yield of major products in subcritical condition was higher than that of major products in supercritical condition. The values of rate constants and activation energy were determined. The overall rates of p-xylene were divided into two equations. Also, the kinetic constants obtained from a simplified reaction pathway showed good agreement with experimental results.
引用
收藏
页码:5576 / 5583
页数:8
相关论文
共 34 条
[1]   PYROLYSIS OF BENZYLPHENYLAMINE NEAT AND WITH TETRALIN, METHANOL, AND WATER SOLVENTS [J].
ABRAHAM, MA ;
KLEIN, MT .
INDUSTRIAL & ENGINEERING CHEMISTRY PRODUCT RESEARCH AND DEVELOPMENT, 1985, 24 (02) :300-306
[2]   A kinetic model for advanced oxidation processes of aromatic hydrocarbons in water:: Application to phenanthrene and nitrobenzene [J].
Beltrán, FJ ;
Rivas, J ;
Alvarez, PM ;
Alonso, MA ;
Acedo, B .
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 1999, 38 (11) :4189-4199
[3]   Products of the gas-phase reactions of OH radicals with p-xylene and 1,2,3-and 1,2,4-trimethylbenzene:: Effect of NO2 concentration [J].
Bethel, HL ;
Atkinson, R ;
Arey, J .
JOURNAL OF PHYSICAL CHEMISTRY A, 2000, 104 (39) :8922-8929
[4]   THE DELPLOT TECHNIQUE - A NEW METHOD FOR REACTION PATHWAY ANALYSIS [J].
BHORE, NA ;
KLEIN, MT ;
BISCHOFF, KB .
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 1990, 29 (02) :313-316
[5]   A lumped kinetic model for liquid-phase catalytic oxidation of p-xylene to terephthalic acid [J].
Cao, Giacomo ;
Pisu, Massimo ;
Morbidelli, Massimo .
CHEMICAL ENGINEERING SCIENCE, 1994, 49 (24B) :5775-5788
[6]   Effect of catalyst concentration and simulation of precipitation processes on liquid phase catalytic oxidation of p-xylene to terephthalic acid [J].
Cincotti, A ;
Orru, R ;
Broi, A ;
Cao, G .
CHEMICAL ENGINEERING SCIENCE, 1997, 52 (21-22) :4205-4213
[7]   Hydrogen peroxide decomposition in supercritical water [J].
Croiset, E ;
Rice, SF ;
Hanush, RG .
AICHE JOURNAL, 1997, 43 (09) :2343-2352
[8]   Elementary reaction mechanism for benzene oxidation in supercritical water [J].
DiNaro, JL ;
Howard, JB ;
Green, WH ;
Tester, JW ;
Bozzelli, JW .
JOURNAL OF PHYSICAL CHEMISTRY A, 2000, 104 (45) :10576-10586
[9]   Catalytic oxidation in supercritical water [J].
Ding, ZY ;
Frisch, MA ;
Li, LX ;
Gloyna, EF .
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 1996, 35 (10) :3257-3279
[10]   REACTION-MECHANISM FOR PHENOL OXIDATION IN SUPERCRITICAL WATER [J].
GOPALAN, S ;
SAVAGE, PE .
JOURNAL OF PHYSICAL CHEMISTRY, 1994, 98 (48) :12646-12652