Survey of Rate Coefficients in the C-H-Cl-O System

Şenkan, Selim

doi:10.1007/978-1-4612-1310-9_4

Cited by 9 publications

(14 citation statements)

References 215 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reactions that can occur between the identified species and free radicals were taken from propane combustion models (GRI-Mech 3 [12]) and from publications concerning TCE combustion in a flame [6,7,13,14], for a total of 330 reactions. The Cl to Cl 2 recombination reaction, Cl ?…”

Section: Chemical Kinetic Modelingmentioning

confidence: 99%

Trichloroethylene Combustion in a Submerged Thermal Plasma: Results and Chemical Kinetics Model

Mabrouk¹,

Marchand²,

Baronnet

et al. 2016

Plasma Chem Plasma Process

View full text Add to dashboard Cite

This work deals with incineration of organic liquid wastes using an oxygen thermal plasma jet, submerged in water. The results presented here concern incineration of trichloroethylene (TCE). During a trial run, the CO 2 and CO content in the exhaust gas is continuously measured; samples taken periodically from the solution are analyzed by appropriate methods: total organic carbon and chlorine content are measured. Process efficiency during tests with a few L/h of TCE is given by the mineralization rate. The trapping rate of chlorine as HCl is near 100 %. The TCE destruction and removal efficiency, measured by MS/GC, is better than 99.9999 %. A simplified kinetic model of gas quenching was constructed from a single-phase plug-flow reactor model taking into account 14 species and 34 reactions. It satisfies the requirements of heat balance and major components analysis, and reveals the major role of the OH radical on the concentrations of CO as well as HCl and/or Cl 2 in the off-gas stream.

show abstract

Section: Chemical Kinetic Modelingmentioning

confidence: 99%

Trichloroethylene Combustion in a Submerged Thermal Plasma: Results and Chemical Kinetics Model

Mabrouk¹,

Marchand²,

Baronnet

et al. 2016

Plasma Chem Plasma Process

View full text Add to dashboard Cite

show abstract

“…14,16,18,19 For CF 3 V(Ø) ) a 0 + a 1 cos(Ø) + a 2 cos(2Ø) + a 3 cos(3Ø) + b 1 sin(Ø) + b 2 sin(2Ø) + b 3 sin(3Ø) (8) number considered. The truncated matrix (in reduced dimensionless form) was diagonalized, and the eigenvalues were used to calculate the partition function, entropy, heat capacity, and so forth.…”

Section: Standard Entropy and Heat Capacities And Hindered Rotationalmentioning

confidence: 99%

“…The bond angles of ∠C 2 H 8 O 9 for CF 3 CCl 2 -H-OH (TS) and CF3 CFCl-H-OH (TS) were 166.0 and 164.0, respectively. There was no significant difference for the bond lengths of C 1 -C 2 between reactants and TSs, but those in products were 0.025 and 0.018 Å shorter than reactants for CF3 C‚Cl 2 and CF 3 C‚FCl, respectively. The dihedral angles between Cl-Cl and Cl-F at the radical site in reactants were 150.6°and 137.0°, respectively.…”

mentioning

confidence: 99%

“…and CF 3 C‚FCl, respectively. Bond lengths of C 2 -H 8 and H 8 -O 9 for CF 3 CCl 2 -H-OH (TS) and CF3 CFCl-H-OH (TS) were 1.223, 1.261 and 1.228, 1.252 Å, respectively. The bond angles of ∠C 2 H 8 O 9 for CF 3 CCl 2 -H-OH (TS) and CF3 CFCl-H-OH (TS) were 166.0 and 164.0, respectively.…”

mentioning

confidence: 99%

“…Bond lengths of C 2 -H 8 and H 8 -O 9 for CF 3 CCl 2 -H-OH (TS) and CF3 CFCl-H-OH (TS) were 1.223, 1.261 and 1.228, 1.252 Å, respectively. The bond angles of ∠C 2 H 8 O 9 for CF 3 CCl 2 -H-OH (TS) and CF3 CFCl-H-OH (TS) were 166.0 and 164.0, respectively. There was no significant difference for the bond lengths of C 1 -C 2 between reactants and TSs, but those in products were 0.025 and 0.018 Å shorter than reactants for CF3 C‚Cl 2 and CF 3 C‚FCl, respectively.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Kinetics and Thermochemistry of the OH Radical Reaction with CF₃CCl₂H and CF₃CFClH

et al. 2000

View full text Add to dashboard Cite

Rate coefficients are reported for the gas-phase reaction of hydroxyl (OH) radicals with CF 3 CCl 2 H (k 1 ) and CF 3 CFClH (k 2 ) over an extended temperature range. The measurements were performed using a laser photolysis/ laser-induced fluorescence (LP/LIF) technique under slow flow conditions at a total pressure of 740 ( 10 Torr. The lower temperature measurements for k 1 and k 2 were in agreement with previous measurements using different techniques. Arrhenius plots of the data exhibit significant curvature and were best described by the following modified Arrhenius expressions (cm 3 molecule -1 s -1 , 2σ error limits): k 1 (296-866 K) ) (2.20 ( 0.25) × 10 -19 T 2.26(0.10 exp(-226 ( 51)/T and k 2 (297-867 K) ) (7.72 ( 0.60) × 10 -20 T 2.35(0.06 exp(-458 ( 30)/T. The experimental measurements were analyzed within the context of transition state theory to provide accurate modified Arrhenius expressions that are applicable to flame conditions. Ab initio calculations were used to evaluate the thermochemical properties of the reactants and products and the partition functions of reactants and their activated complexes. Hydrogen bond dissociation energies (BDE) were also estimated based on calculated enthalpies of formation of reactants and products. An asymmetrical Eckart potential was performed to account for tunneling correction. The resulting TST-based modified Arrhenius expressions (cm 3 molecule -1 s -1 ) were k 1 (250-2000 K) ) 3.25 × 10 -21 T 2.88 exp(-52/T) and k 2 (250-2000 K) ) 4.52 × 10 -22 T 3.18 exp(-362/T). The TST-based modified Arrhenius expression is compared to previous TST and SAR predictions. The results of this study indicate that F substitution at the reaction site has a significant (reductive) effect on hydrochlorofluorocarbon (HCFC) reactivity. This result was also observed in our prior studies of CHFCl 2 and CHF 2 Cl. 4 A similar effect in HCFC reactivity was not observed for changes in F substitution to the reaction site, 6 indicating that the electron-withdrawing effects of the F atoms are limited to the vicinity of the reaction site.

show abstract

The Effects of Cofeeding Chlorinated Hydrocarbons in the Direct Epoxidation of Propylene by Molecular Oxygen

Seubsai¹,

Şenkan²

2011

ChemCatChem

View full text Add to dashboard Cite

Propylene oxide (PO) is a valuable intermediate used in the production of a large variety of valuable consumer products, such as polyurethane foams, polymers, propylene glycol, cosmetics, food emulsifiers and as fumigants and insecticides. [1,2] Over 8 million tons of PO are produced annually from propylene. [1] The technology, economics, and environmental impacts of current as well as alternate propylene epoxidation processes have recently been reviewed. [1,2] Recently, we reported the discovery of a new class of silicasupported RuO 2 -CuO x -NaCl catalysts for the direct epoxidation of propylene by using molecular oxygen under atmospheric pressure. [3] This trimetallic catalyst, at its optimal composition of Ru/Cu/Na = 4:2:1(metal weight ratio, or about 3:4:4 atom ratio) at 12.5 wt % total metal loading, exhibited PO selectivities in the range 40-50 % at propylene conversions of 10-20 % at 240-270 8C and 1 atm (1 atm = 1.0133 10 5 Pa), and it maintained this activity for up to 4-8 h. However, we subsequently observed a slow, but steady decrease in PO selectivity in experiments over longer time periods. This degradation in performance is not acceptable from a practical standpoint if the RuO 2 -CuO x -NaCl/SiO 2 system is to be exploited commercially.Here, we report that the introduction of chlorinated hydrocarbon (CHC) additives to the C 3 H 6 /O 2 feed in the range 1-100 parts per million (ppm by volume) ameliorates the performance degradation problem and enables the steady production of PO, albeit at a decrease in propylene conversion. The beneficial effect of chlorinated hydrocarbons on propylene epoxidation in the RuO 2 -CuO x -NaCl/SiO 2 system appears to be different than the promotional effects observed in Ag catalyzed ethylene oxide (EO) production, [4,5] although some similarities also exist. The promotion of EO by chlorine on silver has been studied in considerable detail in the past and has been attributed to a combination of geometric/ensemble and electronic effects. [4][5][6][7] For example, surface adsorbed Cl atoms (Cl s ) have been suggested to decrease the number of sites for oxygen adsorption, thereby decreasing catalyst activity. Additionally, by site blocking, Cl s has been proposed to reduce the number of neighboring active sites needed for the dissociative adsorption of O 2 . This leads to increased molecular O 2 adsorption (i.e., O s ÀO) as opposed to O s (surface oxygen), thus increasing EO selectivity at the expense of a decrease in activity. In the electronic models, an increase in EO selectivity by chlorine has been attributed to its higher electronegativity. [5,6] This has been suggested to result in the weakening of the AgÀO bond, which leads to increased EO selectivity. [5] However, the same mechanism also results in an increased activation energy for the dissociative chemisorption of O 2 , thereby decreasing the overall activity. [5] In another proposal, EO promotion by chlorine has been attributed to the formation of both surface and subsurface Cl that collectively alter the energ...

show abstract

Survey of Rate Coefficients in the C-H-Cl-O System

Cited by 9 publications

References 215 publications

Trichloroethylene Combustion in a Submerged Thermal Plasma: Results and Chemical Kinetics Model

Trichloroethylene Combustion in a Submerged Thermal Plasma: Results and Chemical Kinetics Model

Kinetics and Thermochemistry of the OH Radical Reaction with CF₃CCl₂H and CF₃CFClH

The Effects of Cofeeding Chlorinated Hydrocarbons in the Direct Epoxidation of Propylene by Molecular Oxygen

Contact Info

Product

Resources

About

Survey of Rate Coefficients in the C-H-Cl-O System

Cited by 9 publications

References 215 publications

Trichloroethylene Combustion in a Submerged Thermal Plasma: Results and Chemical Kinetics Model

Trichloroethylene Combustion in a Submerged Thermal Plasma: Results and Chemical Kinetics Model

Kinetics and Thermochemistry of the OH Radical Reaction with CF3CCl2H and CF3CFClH

The Effects of Cofeeding Chlorinated Hydrocarbons in the Direct Epoxidation of Propylene by Molecular Oxygen

Contact Info

Product

Resources

About

Kinetics and Thermochemistry of the OH Radical Reaction with CF₃CCl₂H and CF₃CFClH