Ionic Strength Effect Triggers Brown Carbon Formation through Heterogeneous Ozone Processing of Ortho-Vanillin
Ionic Strength Effect Triggers Brown Carbon Formation through Heterogeneous Ozone Processing of Ortho-Vanillin
复制标题
离子强度效应通过非均相臭氧处理原香兰素触发棕碳形成
DOI：
10.1021/acs.est.1c00874
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发表时间：
2021
影响因子：
11.4
通讯作者：
Gligorovski Sasho
中科院分区：
文献类型：
--
作者：
Wang Yiqun;Mekic Majda;Li Pan;Deng Huifan;Liu Shiyang;Jiang Bin;Jin Biao;Vione Davide;Gligorovski Sasho
甲氧基苯酚是生物质燃烧产生的一类重要化合物，它们与臭氧反应可在大气中产生二次有机气溶胶。本文采用垂直湿壁流管反应器，研究了离子强度对气相臭氧（O3）与邻香兰素（o-VL）（2-羟基-3-甲氧基苯甲醛）液膜非均相反应的影响。典型的中酸性气溶胶，在固定pH = 5.6时，O3ono-VL （[o-VL] = 1 × 10-5mol L-1）的吸收系数（γ）由na2so4不存在时的γ =（1.9±0.1）× 10 - 7增加到γ =（6.8±0.3）× 10-7atI = 0.2 mol L-1，然后又下降。no3离子的加入只会轻微降低O3的吸收。超高分辨率电喷雾电离傅里叶变换离子回旋共振质谱分析（FT-ICR MS）表明，在so42和no3离子存在下，o3与- vl的非均相反应有利于多核芳香族化合物的形成。no3离子的加入有利于有机硝酸盐中硝基氧（−ONO2）或氧合硝基的形成，这是棕色碳的组成部分，可以影响气候和空气质量。
Methoxyphenols are an important class of compounds emerging from biomass combustion, and their reactions with ozone can generate secondary organic aerosols in the atmosphere. Here, we use a vertical wetted wall flow tube reactor to evaluate the effect of ionic strength on the heterogeneous reaction of gas-phase ozone (O3) with a liquid film ofo-vanillin (o-VL) (2-hydroxy-3-methoxybenzaldehyde), as a proxy for methoxyphenols. Typical for moderately acidic aerosols, at fixed pH = 5.6, the uptake coefficients (γ) of O3ono-VL ([o-VL] = 1 × 10–5mol L–1) increase from γ = (1.9 ± 0.1) × 10–7in the absence of Na2SO4to γ = (6.8 ± 0.3) × 10–7atI= 0.2 mol L–1, and then, it decreases again. The addition of NO3–ions only slightly decreases the uptakes of O3. Ultrahigh-resolution electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) reveals that the formation of multicore aromatic compounds is favored upon heterogeneous O3reaction witho-VL, in the presence of SO42–and NO3–ions. The addition of NO3–ions favors the formation of nitrooxy (−ONO2) or oxygenated nitrooxy group of organonitrates, which are components of brown carbon that can affect both climate and air quality.