Reactions initiated by chlorine atoms can enhance the formation of ozone (O₃) and secondary organic aerosol (SOA) in the troposphere. Environmental chamber experiments were conducted to quantify heterogeneous Cl₂ production from NH₄Cl and NaCl particles exposed to O₃ and hydroxyl radicals (•OH). Observations are inconsistent with models of Cl₂ production resulting solely from surface‐mediated reactions of •OH and suggest that O₃ plays a significant role. The production of Cl₂ increased with relative humidity and decreased in the presence of SOA or nitric oxides (NO_x). Heterogeneous reactive uptake coefficients for the production of Cl₂ from O₃ on pure NH₄Cl ( ) averaged 1.4 ± 1.0 × 10⁻³. Cl₂ production was six times more efficient on NH₄Cl aerosol than on NaCl aerosol. Model calculations under atmospheric conditions suggest this heterogeneous Cl₂ production could increase peak daily O₃ concentrations by over 10%. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3151–3158, 2018

中文翻译：

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氯化物颗粒非均质生产Cl2：组成和相对湿度的影响

由氯原子引发的反应可以增强对流层中臭氧（O ₃）和次级有机气溶胶（SOA）的形成。进行了环境室实验，以量化由暴露于O ₃和羟基自由基（•OH）的NH ₄ Cl和NaCl颗粒产生的异质Cl ₂。观察到的与仅由表面介导的•OH反应产生的Cl ₂产生模型不一致，表明O ₃发挥了重要作用。Cl ₂的产生随着相对湿度的增加而增加，而在SOA或一氧化氮（NO _x）。由O ₃在纯NH ₄ Cl（ ）上生成Cl _2的非均相反应吸收系数平均为1.4±1.0×10 ^-3。在NH ₄ Cl气雾剂上生产Cl _2的效率是在NaCl气雾剂上生产效率的六倍。在大气条件下的模型计算表明，这种不均匀的Cl ₂产生可以使每日最高O ₃浓度增加10％以上。©2018美国化学工程师学会AIChE J，64：3151–3158，2018