气候变化领域集成服务门户(CCPortal): Kinetics of OH + SO2 + M: temperature-dependent rate coefficients in the fall-off regime and the influence of water vapour

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DOI	10.5194/acp-22-4969-2022
	Kinetics of OH + SO2 + M: temperature-dependent rate coefficients in the fall-off regime and the influence of water vapour
	Sun, Wenyu; Berasategui, Matias; Pozzer, Andrea; Lelieveld, Jos; Crowley, John N.
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	4969
结束页码	4984
卷号	22 期号:7 页码:16
英文摘要	The OH-initiated oxidation of SO2 is the dominant, first step in the transformation of this atmospherically important trace gas to particulate sulfate, and accurate rate coefficients for the title reaction under all atmospheric conditions (pressures, temperatures, and humidity) are required to assess its role in, for example, new particle formation. Prior to this study, no temperature-dependent data were available in the fall-off regime for atmospherically relevant bath gases. We thus address an important omission in the kinetic database for this reaction and highlight significant discrepancies in recommended parameterizations. In this work, generation of OH via pulsed laser photolysis at 248 and 351 nm was coupled to its detection by laser-induced fluorescence to obtain rate coefficients (k(1)) for the title reaction at pressures of 14-742 Torr (1 Torr = 1.333 hPa) and temperatures of 220-333 K in N-2 bath gas. In situ SO2 concentrations, central to accurate kinetic measurements under pseudo-first-order conditions, were measured by optical absorption. Under the conditions of the present study, the termolecular reaction between OH and SO2 is in the fall-off regime, and we parameterized the rate coefficients in N-2 in terms of low- (k(1,0)) and high-pressure (k(1,infinity)) limiting rate coefficients and a broadening factor (F-C) to obtain k(1,0)(2)(N) = 3.03 x 10(-31) (T/300 K)(-4.10) cm(6) molecule(-2) s(-1) ,k(1,infinity) = 2.00 x 10(-12) cm(3) molecule(-1) s(-1) , and F-C = 0.58. The effects of water vapour on the title reaction were explored through measurements in N-2-H2O mixtures at 273, 298, and 333 K using the same experimental methods. The rate coefficients are significantly enhanced by the presence of water vapour with k(1,)(0)(2)(H) = 1.65 x 10(-30) (T/300 K)(-4.90) cm(6) molecule(-2) S-1, which indicates that H2O is a factor >5 more efficient in quenching the HOSO2* association complex than N-2. A model-based comparison of our rate coefficients and parameterization with previous literature measurements and recommendations of evaluation panels are presented and discussed. The use of the new parameterization instead of the IUPAC or NASA evaluations, particularly after including H2O as a third-body quencher, leads to a significant (10 %-30 %) reduction in the lifetime of SO2 in some parts of the atmosphere and increases the H2SO4/SO2 ratio concomitantly.
学科领域	Environmental Sciences; Meteorology & Atmospheric Sciences
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Meteorology & Atmospheric Sciences
WOS记录号	WOS:000782409500001
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/273688
作者单位	Max Planck Society
推荐引用方式 GB/T 7714	Sun, Wenyu,Berasategui, Matias,Pozzer, Andrea,et al. Kinetics of OH + SO2 + M: temperature-dependent rate coefficients in the fall-off regime and the influence of water vapour[J],2022,22(7):16.
APA	Sun, Wenyu,Berasategui, Matias,Pozzer, Andrea,Lelieveld, Jos,&Crowley, John N..(2022).Kinetics of OH + SO2 + M: temperature-dependent rate coefficients in the fall-off regime and the influence of water vapour.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(7),16.
MLA	Sun, Wenyu,et al."Kinetics of OH + SO2 + M: temperature-dependent rate coefficients in the fall-off regime and the influence of water vapour".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.7(2022):16.