气候变化领域集成服务门户(CCPortal): Aqueous secondary organic aerosol formation from the direct photosensitized oxidation of vanillin in the absence and presence of ammonium nitrate

CCPortal

DOI	10.5194/acp-22-273-2022
	Aqueous secondary organic aerosol formation from the direct photosensitized oxidation of vanillin in the absence and presence of ammonium nitrate
	Mabato, Beatrix Rosette Go; Lyu, Yan; Ji, Yan; Li, Yong Jie; Huang, Dan Dan; Li, Xue; Nah, Theodora; Lam, Chun Ho; Chan, Chak K.
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	273
结束页码	293
卷号	22 期号:1 页码:21
英文摘要	Vanillin (VL), a phenolic aromatic carbonyl abundant in biomass burning emissions, forms triplet excited states ((VL)-V-3*) under simulated sunlight leading to aqueous secondary organic aerosol (aqS0A) formation. Nitrate and ammonium are among the main components of biomass burning aerosols and cloud or fog water. Under atmospherically relevant cloud and fog conditions, solutions composed of either VL only or VL with ammonium nitrate were subjected to simulated sunlight irradiation to compare aqSOA formation via the direct photosensitized oxidation of VL in the absence and presence of ammonium nitrate. The reactions were characterized by examining the VL decay kinetics, product compositions, and light absorbance changes. Both conditions generated oligomers, functionalized monomers, and oxygenated ring-opening products, and ammonium nitrate promoted functionalization and nitration, likely due to its photolysis products (center dot OH, center dot NO2, and NO2- or HONO). Moreover, a potential imidazole derivative observed in the presence of ammonium nitrate suggested that ammonium participated in the reactions. The majority of the most abundant products from both conditions were potential brown carbon (BrC) chromophores. The effects of oxygen (O-2), pH, and reactants concentration and molar ratios on the reactions were also explored. Our findings show that O-2 plays an essential role in the reactions, and oligomer formation was enhanced at pH <4. Also, functionalization was dominant at low VL concentrations, whereas oligomerization was favored at high VL concentrations. Furthermore, oligomers and hydroxylated products were detected from the oxidation of guaiacol (a non-carbonyl phenol) via VL photosensitized reactions. Last, potential aqSOA formation pathways via the direct photosensitized oxidation of VL in the absence and presence of ammonium nitrate were proposed. This study indicates that the direct photosensitized oxidation of VL may be an important aqSOA source in areas influenced by biomass burning and underscores the importance of nitrate in the aqueous-phase processing of aromatic carbonyls.
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:000740962300001
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/273535
作者单位	City University of Hong Kong; City University of Hong Kong; University of Macau; University of Macau; Jinan University; City University of Hong Kong
推荐引用方式 GB/T 7714	Mabato, Beatrix Rosette Go,Lyu, Yan,Ji, Yan,et al. Aqueous secondary organic aerosol formation from the direct photosensitized oxidation of vanillin in the absence and presence of ammonium nitrate[J],2022,22(1):21.
APA	Mabato, Beatrix Rosette Go.,Lyu, Yan.,Ji, Yan.,Li, Yong Jie.,Huang, Dan Dan.,...&Chan, Chak K..(2022).Aqueous secondary organic aerosol formation from the direct photosensitized oxidation of vanillin in the absence and presence of ammonium nitrate.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(1),21.
MLA	Mabato, Beatrix Rosette Go,et al."Aqueous secondary organic aerosol formation from the direct photosensitized oxidation of vanillin in the absence and presence of ammonium nitrate".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.1(2022):21.