Aqueous phase oxidation of bisulfite influenced by nitrate and its photolysis
| Autor: | Shengyan Jin, Lianghai Xia, Songying Tong, Lu Chen, Lingdong Kong, Kejing Yang, Chao Wang, Lin Wang |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Ammonium sulfate
Environmental Engineering Aqueous solution 010504 meteorology & atmospheric sciences Photodissociation Inorganic chemistry Aqueous two-phase system Halide 010501 environmental sciences 01 natural sciences Pollution Bisulfite chemistry.chemical_compound chemistry Nitrate Environmental Chemistry Sulfate Waste Management and Disposal 0105 earth and related environmental sciences |
| Zdroj: | The Science of the total environment. 785 |
| ISSN: | 1879-1026 |
| Popis: | Nitrate aerosol is ubiquitous in the atmosphere. Nitrate in the particulate and aqueous phase can affect various atmospheric chemical processes through its hygroscopicity and photolysis. The impacts of nitrate photolysis on the heterogeneous oxidation of SO2 have been attracting attention. However, the influence of nitrate on heterogeneous aqueous phase formation of atmospheric sulfate aerosol is still not very clear. In this study, the effects of nitrate on aqueous phase oxidation of bisulfite under different conditions were investigated. Results show that nitrate photolysis can promote the oxidation of bisulfite to sulfate, especially in the presence of O2. It is found that pH plays a significant role in the reaction, and ammonium sulfate has significant impacts on the enhancement of aqueous phase sulfate production through regulating the pH of solution. An apparent synergism is found among halogen chemistry, nitrate and its photochemistry and S (IV) aqueous oxidation, especially the oxidation of halide ions by nitrate and its photolysis and by the intermediate products produced by the free radical chain oxidation of S (IV) in acidic solution, leading to the coupling of the redox cycle of halogen with the oxidation of bisulfite, which promotes the continuous aqueous oxidation of bisulfite and the formation of sulfate. In addition, the role of nitrate itself in the aqueous phase oxidation of bisulfite is revealed. These results provide a new insight into the heterogeneous aqueous phase oxidation pathways and mechanisms of SO2 in cloud and fog droplets and haze particles. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect