Dataset Information

Assessment of Secondary Sulfate Aqueous-Phase Formation Pathways in the Tropical Island City of Haikou: A Chemical Kinetic Perspective.

ABSTRACT: Sulfate (SO₄^2-) is an essential chemical species in atmospheric aerosols and plays an influential role in their physical-chemical characteristics. The mechanisms of secondary SO₄^2- aerosol have been intensively studied in air-polluted cities. However, few studies have focused on cities with good air quality. One-year PM_2.5 samples were collected in the tropical island city of Haikou, and water-soluble inorganic ions, as well as water-soluble Fe and Mn, were analyzed. The results showed that non-sea-salt SO₄^2- (nss-SO₄^2-) was the dominant species of water-soluble inorganic ions, accounting for 40-57% of the total water-soluble inorganic ions in PM_2.5 in Haikou. The S(IV)+H₂O₂ pathway was the main formation pathway for secondary SO₄^2- in wintertime in Haikou, contributing to 57% of secondary SO₄^2- formation. By contrast, 54% of secondary SO₄^2- was produced by the S(IV)+Fe×Mn pathway in summer. In spring and autumn, the S(IV)+H₂O₂, S(IV)+Fe×Mn, and S(IV)+NO₂ pathways contributed equally to secondary SO₄^2- formation. The ionic strength was the controlling parameter for the S(IV)+NO₂ pathway, while pH was identified as a key factor that mediates the S(IV)+H₂O₂ and S(IV)+Fe×Mn pathways to produce secondary SO₄^2-. This study contributes to our understanding of secondary SO₄^2- production under low PM_2.5 concentrations but high SO₄^2- percentages.

SUBMITTER: Wang C

PROVIDER: S-EPMC10892436 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature

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Assessment of Secondary Sulfate Aqueous-Phase Formation Pathways in the Tropical Island City of Haikou: A Chemical Kinetic Perspective.

Wang Chen C Luo Li L Xu Zifu Z Liu Shuhan S Li Yuxiao Y Ni Yuanzhe Y Kao Shuh-Ji SJ

Toxics 20240126 2

Sulfate (SO42-) is an essential chemical species in atmospheric aerosols and plays an influential role in their physical-chemical characteristics. The mechanisms of secondary SO42- aerosol have been intensively studied in air-polluted cities. However, few studies have focused on cities with good air quality. One-year PM2.5 samples were collected in the tropical island city of Haikou, and water-soluble inorganic ions, as well as water-soluble ...[more]

PMID: 38393200

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Dataset Information

Assessment of Secondary Sulfate Aqueous-Phase Formation Pathways in the Tropical Island City of Haikou: A Chemical Kinetic Perspective.

Publications

Assessment of Secondary Sulfate Aqueous-Phase Formation Pathways in the Tropical Island City of Haikou: A Chemical Kinetic Perspective.

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