New insights in atmospheric acid-catalyzed gas phase hydrolysis of formaldehyde: a theoretical study

Environmental contextThe detailed mechanism of hydrolysis of gas-phase ketene to form acetic acid is critical for understanding the formation of certain atmospheric contaminants. This study explores the effect of nitric acid and water on the hydrolysis of ketene in the atmosphere. The calculated results show that nitric acid is an effective catalyst in the hydrolysis of ketene to form acetic acid in atmospheric water-restricted environments. AbstractThe gas-phase hydrolysis of ketene and the unimolecular reaction of 1,1-enediol catalysed by nitric acid and water have been investigated using quantum chemical methods and conventional transition state theory with Eckart tunnelling. The theoretical calculation results show that nitric acid exerts a strong catalytic effect on the hydrolysis of ketene in the gas-phase. The calculated energy barrier for the direct reaction mechanistic pathway is reduced from 42.10kcal mol−1 in the reaction of ketene with water to 3.40kcal mol−1 in the reaction of ketene with water catalysed by HNO3. The catalytic ability of nitric acid is further proven in the hydrogen shift reaction of 1,1-enediol because the energy barrier of the unimolecular reaction of 1,1-enediol is decreased from 44.92kcal mol−1 to −4.51kcal mol−1. In addition, the calculated results indicate that there is competition between the direct and indirect mechanistic pathways with the increase of additional water molecules in the reaction of ketene with water catalysed by HNO3 and (H2O)n (n=1, 2). The calculated kinetics results show that the CH2=C=O+H2O+HNO3 reaction is significant in the gas phase of the atmosphere and the other reactions are negligible owing to the slow reaction rates. However, compared with the CH2=C=O+OH reaction, the CH2=C=O+H2O+HNO3 reaction is very slow and cannot compete with the CH2=C=O+OH reaction. CH2=C=O+OH is the main elimination pathway of ketene in the gas phase of the atmosphere. Our findings reveal that acetic acid may be formed through the hydrolysis of ketene in atmospheric water-restricted environments of the surfaces of aqueous, aerosol and cloud droplets.

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Formic Acid Catalyzed Hydrolysis of SO3in the Gas Phase: A Barrierless Mechanism for Sulfuric Acid Production of Potential Atmospheric Importance

Journal of the American Chemical Society ◽

10.1021/ja207393v ◽

2011 ◽

Vol 133 (43) ◽

pp. 17444-17453 ◽

Cited By ~ 94

Author(s):

Montu K. Hazra ◽

Amitabha Sinha

Keyword(s):

Sulfuric Acid ◽

Formic Acid ◽

Gas Phase ◽

Acid Production ◽

Sulfuric Acid Production ◽

Acid Catalyzed ◽

Hydrolysis Of

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Formic Acid Catalyzed Gas-Phase Reaction of H2O with SO3 and the Reverse Reaction: A Theoretical Study

ChemPhysChem ◽

10.1002/cphc.201100558 ◽

2011 ◽

Vol 13 (1) ◽

pp. 323-329 ◽

Cited By ~ 61

Author(s):

Bo Long ◽

Zheng-wen Long ◽

Yi-bo Wang ◽

Xing-feng Tan ◽

Yu-hua Han ◽

...

Keyword(s):

Formic Acid ◽

Gas Phase ◽

Theoretical Study ◽

Reverse Reaction ◽

Phase Reaction ◽

Gas Phase Reaction ◽

Acid Catalyzed

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Theoretical Studies on Gas-Phase Reactions of Sulfuric Acid Catalyzed Hydrolysis of Formaldehyde and Formaldehyde with Sulfuric Acid and H2SO4···H2O Complex

The Journal of Physical Chemistry A ◽

10.1021/jp312844z ◽

2013 ◽

Vol 117 (24) ◽

pp. 5106-5116 ◽

Cited By ~ 46

Author(s):

Bo Long ◽

Xing-Feng Tan ◽

Chun-Ran Chang ◽

Wei-Xiong Zhao ◽

Zheng-Wen Long ◽

...

Keyword(s):

Sulfuric Acid ◽

Gas Phase ◽

Theoretical Studies ◽

Gas Phase Reactions ◽

Acid Catalyzed ◽

Hydrolysis Of

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Theoretical study of a reaction path via a hydrogen-bonded intermediate for the alkaline hydrolysis of esters in the gas phase

Journal of the Chemical Society Perkin Transactions 2 ◽

10.1039/p29920001629 ◽

1992 ◽

pp. 1629 ◽

Cited By ~ 16

Author(s):

Kenzi Hori

Keyword(s):

Gas Phase ◽

Alkaline Hydrolysis ◽

Theoretical Study ◽

Reaction Path ◽

Hydrolysis Of Esters ◽

Hydrolysis Of ◽

Hydrogen Bonded

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Theoretical Study on the Mechanism for the Formation of Nitro Compounds in Red Oil

Journal of Chemistry ◽

10.1155/2020/2012417 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Meng-Ke Tian ◽

Shuang-Ling Tang ◽

Hong-Bin Tang ◽

Xue-Hai Ju

Keyword(s):

Nitric Acid ◽

Gas Phase ◽

Rate Constants ◽

Density Functional ◽

Theoretical Study ◽

Density Functional Theory Calculations ◽

Nitro Compounds ◽

Functional Theory ◽

Relative Stabilities ◽

Competitive Species

The mechanisms involved in reactions between methane, n-hexane, n-butanol, cyclohexane, and nitric acid were explored by density functional theory calculations. All the calculations in gas phase and n-tributyl phosphate (TBP) solvent were performed at the B3LYP/6–311++G ∗ ∗ and CCSD(T)/6–311++G ∗ ∗ levels of theory. The results showed that TBP has an important effect on the reactions between nitric acid and alkanes or butanol. The reactions were considered as that the radicals (·NO2 and ·NO3 radicals are formed via the HNO3 decomposition under irradiation) initiate the H-atom depletion of the reactants (R), and the produced radicals in red oil combine with ·NO2 radical to form the nitro compounds spontaneously. The rate constants of reactions R + ·NO2 and R + ·NO3 differ substantially, the rate constants of the latter being much larger than those of the former. In the reactions of R + ·NO3, the transition states and products are 20 kJ/mol and 100 kJ/mol or more stable than the reactants, respectively, but the reactions of R + ·NO2 need to overcome energy barriers over 25 kJ/mol. The formations of products mainly depend on the reactions of R + ·NO3. For the same type of alkanes (either chain or cyclic ones), the lower the relative stabilities of carbon-centered radicals are, the more reactive the alkanes are. Cyclohexane is the most competitive species, followed by n-butanol, n-alkanes, and methane which are the least competitive.

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Theoretical Study of the Reaction Mechanism and Role of Water Clusters in the Gas-Phase Hydrolysis of SiCl4

The Journal of Physical Chemistry A ◽

10.1021/jp034618h ◽

2003 ◽

Vol 107 (41) ◽

pp. 8705-8713 ◽

Cited By ~ 24

Author(s):

Stanislav K. Ignatov ◽

Petr G. Sennikov ◽

Alexey G. Razuvaev ◽

Lev A. Chuprov ◽

Otto Schrems ◽

...

Keyword(s):

Reaction Mechanism ◽

Gas Phase ◽

Theoretical Study ◽

Water Clusters ◽

Hydrolysis Of

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13C NMR study of hydrolyzed poly(acrylonitrile)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19840506 ◽

1984 ◽

Vol 49 (2) ◽

pp. 506-512 ◽

Cited By ~ 6

Author(s):

Jan Loevy ◽

Václav Janout ◽

Hana Hrudková

Keyword(s):

Nitric Acid ◽

Nmr Spectroscopy ◽

13C Nmr ◽

Nitrile Group ◽

Nmr Study ◽

Acid Catalyzed ◽

Hydrolysis Of ◽

Poly Acrylonitrile ◽

C Nmr

A method for the determination of chain microstructure of hydrolyzed poly(acrylonitrile) (PAN) and of copolymers of acrylonitrile with acrylamide by means of 13C NMR spectroscopy is described. Besides the overall composition of poly(acrylonitrile-co-acrylamide), this method permits the population of all acrylamide-centered compositional triads to be determined; it is then possible to follow the values of the rate constants of nitrile group hydrolysis in dependence on its neighbours. Under certain circumstances the knowledge of the mentioned triads permits also the copolymerization parameters for copolymerization of acrylonitrile with acrylamide to be determined. It was confirmed that acid-catalyzed hydrolysis of PAN in concentrated nitric acid yields acrylonitrile-acrylamide block copolymers.

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