Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
O- A POSSIBLE NEW ROUTE FOR NOX FORMATION IN FLAMES(NNH )
Autore:
BOZZELLI JW; DEAN AM;
Indirizzi:
EXXON RES & ENGN CO,CORP RES LABS,ROUTE 22 E ANNANDALE NJ 08801 EXXON RES & ENGN CO,CORP RES LABS ANNANDALE NJ 08801
Titolo Testata:
International journal of chemical kinetics
fascicolo: 11, volume: 27, anno: 1995,
pagine: 1097 - 1109
SICI:
0538-8066(1995)27:11<1097:OAPNRF>2.0.ZU;2-H
Fonte:
ISI
Lingua:
ENG
Soggetto:
THEORETICAL CHARACTERIZATION; RADICAL REACTIONS; BIMOLECULAR QRRK; RATE CONSTANTS; COMBUSTION; KINETICS; O-2; CHEMISTRY; NITROGEN; NH2;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
32
Recensione:
Indirizzi per estratti:
Citazione:
J.W. Bozzelli e A.M. Dean, "O- A POSSIBLE NEW ROUTE FOR NOX FORMATION IN FLAMES(NNH )", International journal of chemical kinetics, 27(11), 1995, pp. 1097-1109

Abstract

We propose a new high temperature pathway for NO formation that involves the reaction of NNH with oxygen atoms. This reaction forms the HNNO energized adduct via a rapid combination reaction; HNNO* then rapidly dissociates to NH + NO. The rate constant for O + NNH = NH + NO is calculated via a QRRK chemical activation analysis to be 3.3 x 10(14) T--0.23 exp(+510/T) cm(3) mol(-1) s(-1). This reaction sequence can bean important or even major route to NO formation under certain combustion conditions. The presence of significant quantities of NNH resultsfrom the reaction of H with N-2. The H + N-2 = NNH reaction is only ca. 6 kcal/mol endothermic with a relatively low barrier. The reverse reaction, NNH dissociation, has been reported in the literature to be enhanced by tunneling. Our analysis of NNH dissociation indicates that tunneling dominates. We report a two-term rate constant for NNH dissociation: 3.0 x 10(8) + [M]{1.0 x 10(13)T(0.5) exp(-1540/T)} s(-1). The first term accounts for pressure-independent tunneling from the groundvibrational state, while the second term accounts for collisional activation to higher vibration states from which tunneling can also occur. ([M] is the total concentration in units of mol cm(-3). ) Use of thisdissociation rate constant and microscopic reversibility results in alarge rate constant for the H + N-2 reaction. As a result, we find that NNH = H + N-2 can be partially equilibrated under typical combustion conditions, resulting in NNH concentrations large enough for it to be important in bimolecular reactions. Our analysis of such reactions suggests that the reaction with oxygen atoms is especially important. (C) 1995 John Wiley & Sons, Inc.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 27/10/20 alle ore 10:49:30