The contribution of volatile organic acids to chloride depletion still remains unclear under ambient conditions in the coast and inland. In this work, the heterogeneous reaction of HCOOH on the NaCl surface at a series of relative humidities (RHs) was investigated using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The formate was found to be formed on NaCl surface under dry and wet conditions, accompanied by the corresponding chloride depletion. The adsorbed HCOOH and the formation of formate on NaCl surface decreased with increasing RH below 30% RH. The adsorbed HCOOH decreased, while the formation of formate increased with enhanced RH at 45–70% RH. The variation in the formation of formate with RH suggests that chloride depletion may undergo similar changes. Additionally, the mechanism and kinetics for uptake of HCOOH on NaCl surface at various RHs were discussed and analyzed. Our results highlight the role of heterogeneous chemistry of volatile organic acid in the chloride depletion of NaCl in the coast and inland.

中文翻译：

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HCOOH在不同相对湿度下对NaCl颗粒的非均相反应

在沿海和内陆的环境条件下，挥发性有机酸对氯化物消耗的贡献仍然不清楚。在这项工作中，使用漫反射红外傅里叶变换光谱法（DRIFTS）研究了一系列相对湿度（RH）下HCOOH在NaCl表面上的非均相反应。发现在干燥和湿润的条件下，甲酸盐在NaCl表面形成，并伴随着相应的氯化物消耗。在30％RH以下，随着RH的增加，吸附的HCOOH和在NaCl表面形成的甲酸减少。在45–70％RH时，随着RH的增加，吸附的HCOOH减少，而甲酸的形成增加。与RH形成的甲酸盐的变化表明，氯的​​消耗可能会发生类似的变化。此外，讨论并分析了在各种相对湿度下NaCl表面吸收HCOOH的机理和动力学。我们的结果强调了沿海和内陆挥发性有机酸的异质化学在NaCl的氯化物消耗中的作用。