Thermal decomposition of methyl nitrite: kinetic modeling of detailed product measurements by gas-liquid chromatography and Fourier transform infrared spectroscopy

Journal Article · Thu Sep 22 00:00:00 EDT 1988 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100330a028· OSTI ID:5992224

He, Y; Sanders, W A; Lin, M C

The thermal decomposition of CH/sub 3/ONO was studied in a static reactor at temperatures in the range 450-520 K. Stable products were analyzed by FTIR and gas-liquid chromatography to yield concentration-time profiles as functions of temperature and pressure. The species monitored included CH/sub 3/ONO, CH/sub 2/O, CH/sub 3/OH, NO, N/sub 2/O, and CO. The experimental data were kinetically modeled with the aid of Rice-Ramsperger-Kassel-Marcus (RRKM) calculations for pressure-dependent rate constants. The key reactions of this mechanism are the following: CH/sub 3/ONO ..-->.. CH/sub 3/O + NO (1); CH/sub 3/ONO ..-->.. CH/sub 2/O + HNO (2); CH/sub 3/O + NO ..-->.. CH/sub 3/ONO (3); CH/sub 3/O + NO ..-->.. CH/sub 2/O + HNO (4); CH/sub 3/O + HNO ..-->.. CH/sub 3/OH + NO (5); HNO + HNO ..-->.. N/sub 2/O + H/sub 2/O (7). The results showed that the initiation reaction, (1), is clearly pressure dependent in the temperature and pressure ranges investigated. The data are consistent with the value k/sub 1/ = 10/sup 15.3/plus minus/0.30/ exp((-38,700 /plus minus/ 400)/RT) s/sup -1/ at 710 Torr of He and with the extrapolated high-pressure rate constant k/sub 1//sup infinity/ = 10/sup 16.01/plus minus/0.30/ exp((-39,600 /plus minus/ 400)/RT)s/sup -1/. The rate constant ration k/sub 4//k/sub 3/ for channels 3 and 4 was also found to depend on both temperature and pressure. At 710 Torr, k/sub 3/ = 10/sup 12.96/plus minus/0.30/ exp((0 /plus minus/ 200)/RT) and k/sub 4/ = 10/sup 12.92/plus minus/0.30/ exp((-2050 /plus minus/200)/RT), both in units of cm/sup 3//(mol s). Kinetic modeling of CH/sub 3/OH and N/sub 2/OH formation over the entire range of temperatures and pressures investigated here yielded k/sub 5/ = 10/sup 13.5/plus minus/0.4/ exp((0 /plus minus/ 400)/RT) and k/sub 7/ = 10/sup 8.93/plus minus/0.30/ exp ((-3100 /plus minus/ 300)/RT) cm/sup 3//mol s.

• Research Organization: Catholic Univ. of America, Washington, DC (USA)
• DOE Contract Number: FG05-85ER13373
• OSTI ID: 5992224
• Journal Information: J. Phys. Chem.; (United States), Vol. 92:19
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
NITROUS ACID ESTERS
PYROLYSIS
ABSORPTION SPECTROSCOPY
CHEMICAL REACTION KINETICS
EXPERIMENTAL DATA
FOURIER TRANSFORM SPECTROMETERS
GAS CHROMATOGRAPHY
INFRARED SPECTRA
LIQUID COLUMN CHROMATOGRAPHY
METHOXY RADICALS
ALKOXY RADICALS
CHEMICAL REACTIONS
CHROMATOGRAPHY
DATA
DECOMPOSITION
ESTERS
INFORMATION
KINETICS
MEASURING INSTRUMENTS
NUMERICAL DATA
ORGANIC COMPOUNDS
RADICALS
REACTION KINETICS
SEPARATION PROCESSES
SPECTRA
SPECTROMETERS
SPECTROSCOPY
THERMOCHEMICAL PROCESSES
400800* - Combustion
Pyrolysis
& High-Temperature Chemistry