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Shiroudi A, Czub J, Altarawneh M. Chemical Investigation on the Mechanism and Kinetics of the Atmospheric Degradation Reaction of Trichlorofluoroethene by OH⋅ and Its Subsequent Fate in the Presence of O 2 /NOx. Chemphyschem 2024; 25:e202300665. [PMID: 37983906 DOI: 10.1002/cphc.202300665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 11/17/2023] [Accepted: 11/20/2023] [Indexed: 11/22/2023]
Abstract
The M06-2X/6-311++G(d,p) level of theory was used to examine the degradation of Trichlorofluoroethene (TCFE) initiated by OH⋅ radicals. Additionally, the coupled-cluster single-double with triple perturbative [CCSD(T)] method was employed to refine the single-point energies using the complete basis set extrapolation approach. The results indicated that OH-addition is the dominant pathway. OH⋅ adds to both the C1 and C2 carbons, resulting in the formation of the C(OH)Cl2 -⋅CClF and ⋅CCl2 -C(OH)ClF species. The associated barrier heights were determined to be 1.11 and -0.99 kcal mol-1 , respectively. Furthermore, the energetic and thermodynamic parameters show that pathway 1 exhibits greater exothermicity and exergonicity compared to pathway 2, with differences of 8.11 and 8.21 kcal mol-1 , correspondingly. The primary pathway involves OH addition to the C2 position, with a rate constant of 6.2×10-13 cm3 molecule-1 sec-1 at 298 K. This analysis served to estimate the atmospheric lifetime, along with the photochemical ozone creation potential (POCP) and ozone depletion potential (ODP). It yielded an atmospheric lifetime of 8.49 days, an ODP of 4.8×10-4 , and a POCP value of 2.99, respectively. Radiative forcing efficiencies were also estimated at the M06-2X/6-311++G(d,p) level. Global warming potentials (GWPs) were calculated for 20, 100, and 500 years, resulting in values of 9.61, 2.61, and 0.74, respectively. TCFE is not expected to make a significant contribution to the radiative forcing of climate change. The results obtained from the time-dependent density functional theory (TDDFT) indicated that TCFE and its energized adducts are unable to photolysis under sunlight in the UV and visible spectrum. Secondary reactions involve the [TCFE-OH-O2 ]⋅ peroxy radical, leading subsequently to the [TCFE-OH-O]⋅ alkoxy radical. It was found that the alkoxy radical resulting from the peroxy radical can lead to the formation of phosgene (COCl2 ) and carbonyl chloride fluoride (CClFO), with phosgene being the primary product.
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Affiliation(s)
- Abolfazl Shiroudi
- Department of Physical Chemistry, Gdańsk University of Technology, Narutowicza 11/12, Gdańsk, 80-233, Poland
- BioTechMed Center, Gdańsk University of Technology, Gdańsk, 80-233, Poland
| | - Jacek Czub
- Department of Physical Chemistry, Gdańsk University of Technology, Narutowicza 11/12, Gdańsk, 80-233, Poland
- BioTechMed Center, Gdańsk University of Technology, Gdańsk, 80-233, Poland
| | - Mohammednoor Altarawneh
- United Arab Emirates University, Department of Chemical and Petroleum Engineering, Sheikh Khalifa bin Zayed Street, Al-Ain, 15551, United Arab Emirates
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Balsini SS, Shiroudi A, Hatamjafari F, Zahedi E, Pourshamsian K, Oliaey AR. Understanding the kinetics and atmospheric degradation mechanism of chlorotrifluoroethylene (CF 2CFCl) initiated by OH radicals. Phys Chem Chem Phys 2023; 25:13630-13644. [PMID: 37144555 DOI: 10.1039/d3cp00161j] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The atmospheric degradation of chlorotrifluoroethylene (CTFE) by OH˙ was investigated using density functional theory (DFT). The potential energy surfaces were also defined in terms of single-point energies derived from the linked cluster CCSD(T) theory. With an energy barrier of -2.62 to -0.99 kcal mol-1 using the M06-2x method, the negative temperature dependence was determined. The OH˙ attack on Cα and Cβ atoms (labeled pathways R1 and R2, respectively) shows that reaction R2 is 4.22 and 4.42 kcal mol-1, respectively, more exothermic and exergonic than reaction R1. The main pathway should be the addition of OH˙ to the β-carbon, resulting in ˙CClF-CF2OH species. At 298 K, the calculated rate constant was 9.87 × 10-13 cm3 molecule-1 s-1. The TST and RRKM calculations of rate constants and branching ratios were performed at P = 1 bar and in the fall-off pressure regime over the temperature range of 250-400 K. The formation of HF and ˙CClF-CFO species via the 1,2-HF loss process is the most predominant pathway both kinetically and thermodynamically. With increasing temperature and decreasing pressure, the regioselectivity of unimolecular processes of energized adducts [CTFE-OH]˙ gradually decreases. Pressures greater than 10-4 bar are often adequate for assuring saturation of the estimated unimolecular rates when compared to the RRKM rates (in high-pressure limit). Subsequent reactions involve the addition of O2 to the [CTFE-OH]˙ adducts at the α-position of the OH group. The [CTFE-OH-O2]˙ peroxy radical primarily reacts with NO and then directly decomposes into NO2 and oxy radicals. "Carbonic chloride fluoride", "carbonyl fluoride", and "2,2-difluoro-2-hydroxyacetyl fluoride" are predicted to be stable products in an oxidative atmosphere.
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Affiliation(s)
- Saber Safari Balsini
- Department of Chemistry, Tonekabon Branch, Islamic Azad University, Tonekabon, Iran.
| | - Abolfazl Shiroudi
- Department of Chemistry, Tonekabon Branch, Islamic Azad University, Tonekabon, Iran.
- Department of Physical Chemistry, Gdańsk University of Technology, Narutowicza 11/12, Gdańsk 80-233, Poland.
| | - Farhad Hatamjafari
- Department of Chemistry, Tonekabon Branch, Islamic Azad University, Tonekabon, Iran.
| | - Ehsan Zahedi
- Department of Chemistry, Shahrood Branch, Islamic Azad University, Shahrood, Iran
| | - Khalil Pourshamsian
- Department of Chemistry, Tonekabon Branch, Islamic Azad University, Tonekabon, Iran.
| | - Ahmad Reza Oliaey
- Department of Chemistry, Tonekabon Branch, Islamic Azad University, Tonekabon, Iran.
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Lei X, Chen D, Wang W, Liu F, Wang W. Quantum chemical studies of the OH-initiated oxidation reactions of propenols in the presence of O2. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1537527] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Xiaoyang Lei
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi’an, People’s Republic of China
| | - Dongping Chen
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi’an, People’s Republic of China
| | - Weina Wang
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi’an, People’s Republic of China
| | - Fengyi Liu
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi’an, People’s Republic of China
| | - Wenliang Wang
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi’an, People’s Republic of China
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Parandaman A, Kumar M, Francisco JS, Sinha A. Organic Acid Formation from the Atmospheric Oxidation of Gem Diols: Reaction Mechanism, Energetics, and Rates. J Phys Chem A 2018; 122:6266-6276. [DOI: 10.1021/acs.jpca.8b01773] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Arathala Parandaman
- Department of Chemistry and Biochemistry, University of California—San Diego, La Jolla, California 92093, United States
| | - Manoj Kumar
- Department of Chemistry, University of Nebraska—Lincoln, Lincoln, Nebraska 68588, United States
| | - Joseph S. Francisco
- Department of Chemistry, University of Nebraska—Lincoln, Lincoln, Nebraska 68588, United States
| | - Amitabha Sinha
- Department of Chemistry and Biochemistry, University of California—San Diego, La Jolla, California 92093, United States
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Theoretical Kinetic and Mechanistic Studies on the Reactions of CF₃CBrCH₂ (2-BTP) with OH and H Radicals. Molecules 2017; 22:molecules22122140. [PMID: 29210996 PMCID: PMC6150020 DOI: 10.3390/molecules22122140] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 11/24/2017] [Accepted: 11/29/2017] [Indexed: 11/24/2022] Open
Abstract
CF3CBrCH2 (2-bromo-3,3,3-trifluoropropene, 2-BTP) is a potential replacement for CF3Br; however, it shows conflicted inhibition and enhancement behaviors under different combustion conditions. To better understand the combustion chemistry of 2-BTP, a theoretical study has been performed on its reactions with OH and H radicals. Potential energy surfaces were exhaustively explored by using B3LYP/aug-cc-pVTZ for geometry optimizations and CCSD(T)/aug-cc-pVTZ for high level single point energy refinements. Detailed kinetics of the major pathways were predicted by using RRKM/master-equation methodology. The present predictions imply that the –C(Br)=CH2 moiety of 2-BTP is most likely to be responsible for its fuel-like property. For 2-BTP + OH, the addition to the initial adduct (CF3CBrCH2OH) is the dominant channel at low temperatures, while the substitution reaction (CF3COHCH2 + Br) and H abstraction reaction (CF3CBrCH + H2O) dominates at high temperatures and elevated pressures. For 2-BTP + H, the addition to the initial adduct (CF3CBrCH3) also dominates the overall kinetics at low temperatures, while Br abstraction reaction (CF3CCH2 + HBr) and β-scission of the adduct forming CF3CHCH2 + Br dominates at high temperatures and elevated pressures. Compared to 2-BTP + OH, the 2-BTP + H reaction tends to have a larger effect on flame suppression, given the fact that it produces more inhibition species.
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The role of torsional motion on the properties of propiolic acid and its H/D isotopic analogs: A density functional study using SCTST and a full anharmonic VPT2 model. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.01.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Amedro D, Vereecken L, Crowley JN. Kinetics and mechanism of the reaction of perfluoro propyl vinyl ether (PPVE, C₃F₇OCH=CH₂) with OH: assessment of its fate in the atmosphere. Phys Chem Chem Phys 2015; 17:18558-66. [PMID: 26112907 DOI: 10.1039/c5cp02233a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Absolute rate coefficients for the reaction between OH radicals and perfluoro propyl vinyl ether (PPVE) were obtained using the technique of pulsed laser photolysis with the detection of OH radicals by laser induced fluorescence. Rate coefficients were measured over a range of temperatures (212-298 K) and at either 50 or 200 Torr bath-gas (N2 or N2/O2). The temperature dependence of the rate coefficient is given by k1(212-298 K) = (4.88 ± 0.49) × 10(-13) exp[(564 ± 10)/T] cm(3) molecule(-1) s(-1) with a value at room temperature of (3.4 ± 0.3) × 10(-12) cm(3) molecule(-1) s(-1). No pressure dependence was observed, indicating that the reaction is at the high pressure limit under atmospheric conditions. The accuracy of the rate coefficient obtained was enhanced by on-line optical absorption measurements of PPVE at 184.95 nm using a value of σ(184.95 nm) = (5.64 ± 0.28) × 10(-18) cm(2) molecule(-1) determined in this work. An atmospheric lifetime of a few days for PPVE was calculated. Extensive quantum chemical calculations as a complement to the experimental work are presented in order to determine its probable tropospheric degradation mechanism.
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Affiliation(s)
- D Amedro
- Max Planck Institute for Chemistry, Atmospheric Sciences, Hahn-Meitner-Weg 1, Mainz, Germany.
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Vereecken L, Crowley JN, Amedro D. Theoretical study of the OH-initiated atmospheric oxidation mechanism of perfluoro methyl vinyl ether, CF3OCFCF2. Phys Chem Chem Phys 2015; 17:28697-704. [DOI: 10.1039/c5cp04839g] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The fluorinated product glycolaldehyde can be catalytically converted to glyoxal + HF by H2O.
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Affiliation(s)
- L. Vereecken
- Max Planck Institute for Chemistry
- Atmospheric Sciences
- Mainz
- Germany
| | - J. N. Crowley
- Max Planck Institute for Chemistry
- Atmospheric Sciences
- Mainz
- Germany
| | - D. Amedro
- Max Planck Institute for Chemistry
- Atmospheric Sciences
- Mainz
- Germany
- Division of Chemistry and Chemical Engineering
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