Aqueous Reactions of Sulfate Radical-Anions with Nitrophenols in Atmospheric Context

Nitrophenols, hazardous environmental pollutants, react promptly with atmospheric oxidants such as hydroxyl or nitrate radicals. This work aimed to estimate how fast nitrophenols are removed from the atmosphere by the aqueous-phase reactions with sulfate radical-anions. The reversed-rates method was applied to determine the relative rate constants for reactions of 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, and 2,4,6-trinitrophenol with sulfate radical-anions generated by the autoxidation of sodium sulfite catalyzed by iron(III) cations at ~298 K. The constants determined were: 9.08 × 108, 1.72 × 109, 6.60 × 108, 2.86 × 108, and 7.10 × 107 M−1 s−1, respectively. These values correlated linearly with the sums of Brown substituent coefficients and with the relative strength of the O–H bond of the respective nitrophenols. Rough estimation showed that the gas-phase reactions of 2-nitrophenol with hydroxyl or nitrate radicals dominated over the aqueous-phase reaction with sulfate radical-anions in deliquescent aerosol and haze water. In clouds, rains, and haze water, the aqueous-phase reaction of 2-nitrophenol with sulfate radical-anions dominated, provided the concentration of the radical-anions was not smaller than that of the hydroxyl or nitrate radicals. The results presented may be also interesting for designers of advanced oxidation processes for the removal of nitrophenol.

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Kinetic study of the gas-phase reaction of atomic chlorine with a series of aldehydes

Atmospheric Chemistry and Physics ◽

10.5194/acp-5-3433-2005 ◽

2005 ◽

Vol 5 (12) ◽

pp. 3433-3440 ◽

Cited By ~ 19

Author(s):

D. Rodríguez ◽

A. Rodríguez ◽

A. Notario ◽

A. Aranda ◽

Y. Díaz-de-Mera ◽

...

Keyword(s):

Relative Rate ◽

Weighted Average ◽

Rate Coefficients ◽

Phase Reaction ◽

Additional Information ◽

Relative Rate Constants ◽

Relative Measurements ◽

First Time ◽

Structure Versus ◽

Atomic Chlorine

Abstract. The reactions of Cl atoms with a series of unsaturated aldehydes have been investigated for the first time using a relative method. In order to obtain additional information for a qualitative structure versus reactivity discussion, we have also determined the rate coefficients for the reactions of atomic chlorine with their respective saturated aldehydes. These relative measurements were performed at room temperature and atmospheric pressure of air and N2, by using ethane, propene and 1-butene as reference compounds. The weighted average relative rate constants obtained, kCl±2σ (in units of cm3 molecule−1 s−1) were: trans-2-pentenal (1.31±0.19)×10−10; trans-2-hexenal (1.92±0.22)×10−10; trans-2-heptenal (2.40±0.29)×10−10; n-pentanal (2.56±0.27)×10−10; n-hexanal (2.88±0.37)×10−10; n-heptanal (3.00±0.34)×10−10. Finally, results and atmospheric implications are discussed and compared with the reactivity with OH and NO3 radicals.

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Absolute and relative rate constants for the gas-phase reaction of OH radicals with CH3NO2, CD3NO2 and CH3CH2CH3 at 295 K and 1 ATM

Chemical Physics Letters ◽

10.1016/0009-2614(88)87430-x ◽

1988 ◽

Vol 146 (3-4) ◽

pp. 197-203 ◽

Cited By ~ 11

Author(s):

Ole J. Nielsen ◽

Howard W. Sidebottom ◽

Denis J. O'Farrell ◽

Michael Donlon ◽

Jack Treacy

Keyword(s):

Gas Phase ◽

Rate Constants ◽

Relative Rate ◽

Oh Radicals ◽

Phase Reaction ◽

Gas Phase Reaction ◽

Relative Rate Constants

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Gas-phase reactions of Cl atoms with hydrochloroethers: relative rate constants and their correlation with substituents' electronegativities

Journal of Physical Organic Chemistry ◽

10.1002/poc.1362 ◽

2008 ◽

Vol 21 (5) ◽

pp. 393-396 ◽

Cited By ~ 11

Author(s):

Pablo R. Dalmasso ◽

Raúl A. Taccone ◽

Jorge D. Nieto ◽

Pablo M. Cometto ◽

Silvia I. Lane

Keyword(s):

Gas Phase ◽

Rate Constants ◽

Relative Rate ◽

Gas Phase Reactions ◽

Relative Rate Constants ◽

Cl Atoms

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Kinetic study of the gas-phase reaction of atomic chlorine with a series of aldehydes

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-5-5167-2005 ◽

2005 ◽

Vol 5 (4) ◽

pp. 5167-5182 ◽

Cited By ~ 3

Author(s):

D. Rodríguez ◽

A. Rodríguez ◽

A. Notario ◽

A. Aranda ◽

Y. Díaz-de-Mera ◽

...

Keyword(s):

Relative Rate ◽

Weighted Average ◽

Rate Coefficients ◽

Phase Reaction ◽

Additional Information ◽

Relative Rate Constants ◽

Relative Measurements ◽

First Time ◽

Structure Versus ◽

Atomic Chlorine

Abstract. The reactions of Cl atoms with a series of unsaturated aldehydes have been investigated for the first time using a relative method. In order to obtain additional information for a qualitative structure versus reactivity discussion, we have also determined, for the first time, the rate coefficients for the reactions of atomic chlorine with their respective saturated aldehydes. These relative measurements were performed at room temperature and atmospheric pressure of air and N2, by using ethane, propene and 1-butene as reference compounds. The weighted average relative rate constants obtained, kCl±2σ (in units of cm3 molecule−1 s−1) were: trans-2-pentenal (1.31±0.19)×10−10; trans-2-hexenal (1.92±0.22)×10−10; trans-2-heptenal (2.40±0.29)×10−10; n-pentanal (2.56±0.27)×10−10; n-hexanal (2.88±0.37)×10−10; n-heptanal (3.00±0.34)×10−10. Finally, results and atmospheric implications are discussed and compared with the reactivity with OH and NO3 radicals.

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Tropospheric Aqueous-phase Oxidation of Green Leaf Volatiles with Hydroxyl, Sulfate and Nitrate Radicals

10.5194/egusphere-egu2020-4909 ◽

2020 ◽

Author(s):

Kumar Sarang ◽

Tobias Otto ◽

Krzysztof Rudzinski ◽

Irena Grgic ◽

Klara Nestorowicz ◽

...

Keyword(s):

Gas Phase ◽

Aqueous Phase ◽

Rate Constants ◽

Flash Photolysis ◽

Green Leaf Volatiles ◽

Phase Reaction ◽

Leaf Volatiles ◽

Nitrate Radicals ◽

Kinetic Investigations ◽

Atmospherically Relevant

Introduction &#160;Numerous green leaf volatiles (GLVs) are released into the atmosphere due to the stress, cell damage or wounding. Fog forming over vegetation takes up these compounds, promoting their aqueous-phase oxidation to less volatile compounds. The droplets eventually dry out, leaving behind the secondary organic aerosol (SOA). These pathways are still poorly recognized as potentially novel routes for the formation of atmospheric SOA. Kinetic investigations of GLVs in the gas phase have already been reported by Shalamzari et. al. 2014, Davis et. al. 2011 and many others, while there is no kinetic data on the aqueous phase reactions of selected C6 and C5 GLVs. In the present study, we focussed on the kinetic studies of GLVs with the hydroxyl, sulfate and nitrate radicals as a possible source of aqueous SOA.Experimental method &#160;The rate constants of reactions of GLVs with atmospherically relevant radicals were studied using a laser flash photolysis-laser long path absorption (LFP-LLPA).&#160;Kinetic investigations of GLVs with hydroxyl radicals were performed using competition kinetics, where H2O2 (2 x 10-4 mol L-1) was used as a radical precursor and KSCN (2 x 10-5 mol L-1) as a reference compound. The method is similar to that introduced by Behar, et al. 1972. Kinetic measurements of sulfate and nitrate radicals with GLVs, were done using a direct flash photolysis method, where sodium persulfate (5 x 10-4 mol L-1) was the precursor in the generation of SO4&#8226;&#42999;&#160;and sodium nitrate (1 x 10-1 mol L-1) and sodium sulfate (3 x 10-2 mol L-1) were the precursor for the generation of nitrate radicals.Conclusions &#160;In the present study, we explored the kinetics of aqueous-phase reactions of three GLVs- 1-penten-3-ol, cis-2-hexen-1-ol and 2-E-hexenal - with atmospheric radicals SO4&#8226;&#42999;, &#8226;OH and NO3&#8226;. The second-order rate constants were determined for a temperature range of 278 K to 318 K. A weak temperature dependence was observed for the aqueous-phase kinetics of all three GLVs with selected atmospherically relevant radicals. To explain the weak temperature dependence of aqueous-phase reaction of GLVs with atmospheric radicals, rate constants were investigated for the diffusion limitation. The atmospheric significance of the aqueous-phase reaction was evaluated, by calculating aqueous-phase lifetime and their relative rate to the gas phase reactions with respective radicals, which clearly demonstrated their importance above the gas-phase reactions in tropospheric aqueous-phase. The present work is a part of the bigger research project on the aqueous-phase reactions of a series of atmospherically relevant GLVs whereas a next step oxidation products in the aqueous-phase are being investigated at a present stage.&#160;This project is supported by the European Union&#8217;s Horizon 2020 research and innovation programme under the Marie Sk&#322;odowska-Curie grant agreement No. 711859 and by financial resources for science in the years 2017-2021 awarded by the Polish Ministry of Science and Higher Education for the implementation of an international co-financed project. The research project was also partially supported by funding under Project CREATE of European Union&#8217;s H2020 and ERASMUS PLUS staff mobility programme.

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Kinetics of the successive chlorination of 1,2-dichloroethane in the liquid phase

Australian Journal of Chemistry ◽

10.1071/ch9691177 ◽

1969 ◽

Vol 22 (6) ◽

pp. 1177 ◽

Cited By ~ 6

Author(s):

DS Caines ◽

RB Paton ◽

DA Williams ◽

PR Wilkinson

Keyword(s):

Liquid Phase ◽

Rate Constants ◽

Relative Rate ◽

Stirred Tank ◽

Continuous Stirred Tank Reactor ◽

Alternative Pathways ◽

Tank Reactor ◽

Relative Rate Constants ◽

Continuous Stirred Tank ◽

Kinetics Of

Liquid 1,2-dichloroethane has been chlorinated by dissolved chlorine to a succession of chloroethanes up to the ultimate hexachloroethane. The results of both batch and continuous stirred tank reactor systems have been analysed by computer techniques to give a set of relative rate constants from which one can predict the product composition for a given chlorine uptake, the aim in this work being to optimize the production of tetrachloroethanes. An unusual feature of the kinetics is that 1,1,1,2- and 1,1,2,2-tetrachloroethanes provide alternative pathways between 1,1,2-trichloroethane and pentachloroethane.

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Simulation of atmospheric mercury depletion events (AMDEs) during polar springtime using the MECCA box model

Atmospheric Chemistry and Physics ◽

10.5194/acp-8-7165-2008 ◽

2008 ◽

Vol 8 (23) ◽

pp. 7165-7180 ◽

Cited By ~ 35

Author(s):

Z.-Q. Xie ◽

R. Sander ◽

U. Pöschl ◽

F. Slemr

Keyword(s):

Aqueous Phase ◽

Ozone Depletion ◽

Elemental Mercury ◽

Atmospheric Mercury ◽

Box Model ◽

Rate Coefficients ◽

Mercury Species ◽

Phase Reaction ◽

Gaseous Elemental Mercury ◽

Sea Salt Aerosol

Abstract. Atmospheric mercury depletion events (AMDEs) during polar springtime are closely correlated with bromine-catalyzed tropospheric ozone depletion events (ODEs). To study gas- and aqueous-phase reaction kinetics and speciation of mercury during AMDEs, we have included mercury chemistry into the box model MECCA (Module Efficiently Calculating the Chemistry of the Atmosphere), which enables dynamic simulation of bromine activation and ODEs. We found that the reaction of Hg with Br atoms dominates the loss of gaseous elemental mercury (GEM). To explain the experimentally observed synchronous depletion of GEM and O3, the reaction rate of Hg+BrO has to be much lower than that of Hg+Br. The synchronicity is best reproduced with rate coefficients at the lower limit of the literature values for both reactions, i.e. kHg+Br≈3×10−13 and kHg+BrO≤1×10−15 cm3 molecule−1 s−1, respectively. Throughout the simulated AMDEs, BrHgOBr was the most abundant reactive mercury species, both in the gas phase and in the aqueous phase. The aqueous-phase concentrations of BrHgOBr, HgBr2, and HgCl2 were several orders of magnitude larger than that of Hg(SO3)22−. Considering chlorine chemistry outside depletion events (i.e. without bromine activation), the concentration of total divalent mercury in sea-salt aerosol particles (mostly HgCl42−) was much higher than in dilute aqueous droplets (mostly Hg(SO3)22−), and did not exhibit a diurnal cycle (no correlation with HO2 radicals).

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Kinetic study of the photochemical changes of (ZZ)-bilirubin IX α bound to human serum albumin. Demonstration of (EZ)-bilirubin IX α as an intermediate in photochemical changes from (ZZ)-bilirubin IX α to (EZ)-cyclobilirubin IX α

Biochemical Journal ◽

10.1042/bj2260251 ◽

1985 ◽

Vol 226 (1) ◽

pp. 251-258 ◽

Cited By ~ 25

Author(s):

S Itoh ◽

S Onishi

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Kinetic Study ◽

Human Serum ◽

Photochemical Reaction ◽

Relative Rate ◽

Significant Preference ◽

Geometrical Isomers ◽

Relative Rate Constants

The present study was performed to elucidate why the photochemical reaction of (ZZ)-bilirubin bound to human serum albumin is singularly selective, and only one of the two (EZ)- and (ZE)-bilirubins, the (ZE)-isomer, is produced. In a kinetic study of the photochemical reaction in vitro, the sum of the relative rate constants of photochemical transformation of (EZ)-bilirubin into both (EZ)-cyclobilirubin and (ZZ)-bilirubin, with a significant preference for the former, was proved to be considerably larger than that of the transformation of (ZZ)-bilirubin into (EZ)-bilirubin. Therefore only one of the geometrical isomers, namely (ZE)-bilirubin, is apparently formed. It was concluded that (EZ)-bilirubin photochemically undergoes (EZ)-cyclization, i.e. structural photoisomerization, while bound to its high-affinity site on human serum albumin, and is an intermediate in the transformation of (ZZ)-bilirubin into (EZ)-cyclobilirubin.

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RECOMBINATION OF OPPOSITELY CHARGED AQUEOUS CLUSTER IONS USING ELECTROSTATICALLY MERGED ION BEAMS

Surface Review and Letters ◽

10.1142/s0218625x96001170 ◽

1996 ◽

Vol 03 (01) ◽

pp. 655-660 ◽

Cited By ~ 1

Author(s):

B. PLASTRIDGE ◽

K.A. COWEN ◽

D.A. WOOD ◽

M.H. COHEN ◽

J.V. COE

Keyword(s):

Rate Constants ◽

Cluster Size ◽

Collision Energy ◽

Relative Rate ◽

Center Of Mass ◽

Cluster Ions ◽

Charged Cluster ◽

Relative Rate Constants ◽

Oppositely Charged ◽

Electrostatic Quadrupole

A new method for studying cluster-cluster interactions is introduced which involves merging mass-selected beams of oppositely charged cluster ions with an electrostatic quadrupole deflector. Recombination is monitored by measuring the rate of fast neutral production. Relative rate constants have been measured for the reaction of H 3O+( H 2 O )n+ OH −( H 2 O )m as a function of cluster size (m=n=0–3), which display a pronounced enhancement with clustering. Relative rate constants have also been measured as a function of center-of-mass collision energy for a heavily clustered reaction (n=3, m=3) and a lightly clustered reaction (n=1, m=0) revealing that clustering produces a dramatic change in the reaction mechanism.

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