Towards understanding the role of amines in the SO2 hydration and the contribution of the hydrated product to new particle formation in the Earth's atmosphere

Guochun Lv; Alexey B Nadykto; Xiaomin Sun; Chenxi Zhang; Yisheng Xu

doi:10.1016/j.chemosphere.2018.04.117

Towards understanding the role of amines in the SO₂ hydration and the contribution of the hydrated product to new particle formation in the Earth's atmosphere

Chemosphere. 2018 Aug:205:275-285. doi: 10.1016/j.chemosphere.2018.04.117. Epub 2018 Apr 21.

Authors

Guochun Lv¹, Alexey B Nadykto², Xiaomin Sun³, Chenxi Zhang⁴, Yisheng Xu⁵

Affiliations

¹ Environment Research Institute, Shandong University, Jinan, 250100, China.
² Department of Applied Mathematics, Moscow State University of Technology "Stankin", Vadkovsky 1, Moscow, 127055, Russia.
³ Environment Research Institute, Shandong University, Jinan, 250100, China. Electronic address: sxmwch@sdu.edu.cn.
⁴ College of Biological and Environmental Engineering, Binzhou University, Binzhou, 256600, China.
⁵ State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China. Electronic address: xuys@craes.org.cn.

PMID: 29702347
DOI: 10.1016/j.chemosphere.2018.04.117

Abstract

By theoretical calculations, the gas-phase SO₂ hydration reaction assisted by methylamine (MA) and dimethylamine (DMA) was investigated, and the potential contribution of the hydrated product to new particle formation (NPF) also was evaluated. The results show that the energy barrier for aliphatic amines (MA and DMA) assisted SO₂ hydration reaction is lower than the corresponding that of water and ammonia assisted SO₂ hydration. In these hydration reactions, nearly barrierless reaction (only a barrier of 0.1 kcal mol^-1) can be found in the case of SO₂ + 2H₂O + DMA. These lead us to conclude that the SO₂ hydration reaction assisted by MA and DMA is energetically facile. The temporal evolution for hydrated products (CH₃NH₃⁺-HSO₃^--H₂O or (CH₃)₂NH₂⁺-HSO₃^--H₂O) in molecular dynamics simulations indicates that these complexes can self-aggregate into bigger clusters and can absorb water and amine molecules, which means that these hydrated products formed by the hydration reaction may serve as a condensation nucleus to initiate the NPF.

Keywords: Amines; Hydrated products; Hydration of SO(2); New particle formation; Theoretical calculations.

MeSH terms

Amines / chemistry*
Atmosphere*
Earth, Planet*
Sulfur Dioxide / chemistry*
Water / chemistry*

Substances

Amines
Water
Sulfur Dioxide