School of Metallurgy, Northeastern University, Shenyang, 110819, China.
School of Metallurgy, Northeastern University, Shenyang, 110819, China.
Environ Pollut. 2018 Dec;243(Pt A):679-686. doi: 10.1016/j.envpol.2018.09.039. Epub 2018 Sep 8.
The generation of HONO and NO by the photolysis of nitrates in the presence of humic acids (HA) was measured under various conditions. The photolysis experiments of HA, KNO and KNO/HA under simulated sunlight was carried out by a flow tube reactor at ambient temperature and pressure. HONO and NO were major products by the photolysis of KNO. By contrast, the photolysis of HA and KNO/HA mainly generated HONO. HA significantly enhanced the formation of HONO during the photolysis process of KNO. With increasing the KNO mass, the HONO formation rate (R) on KNO/HA increased while the photolysis rate normalized by the KNO mass exhibited an opposite trend. R on KNO/HA linearly increased with irradiation intensity (88-262 W/m) and relative humidity (7-70%), whereas it linearly decreased with the pH (pH = 2-12). In addition, the reaction paths of the HONO formation by the photolysis of nitrates in the presence of HA were proposed according to experimental results. Finally, atmospheric implications of the enhanced HONO formation by the photolysis of nitrates in the presence of HA were discussed.
在各种条件下测量了在腐殖酸 (HA) 存在下硝酸盐光解生成 HONO 和 NO 的情况。在环境温度和压力下，通过流动管反应器进行了 HA、KNO 和 KNO/HA 的模拟太阳光光解实验。KNO 的光解主要生成 HONO 和 NO。相比之下，HA 和 KNO/HA 的光解主要生成 HONO。HA 在 KNO 的光解过程中显著促进了 HONO 的形成。随着 KNO 质量的增加，KNO/HA 上的 HONO 生成速率 (R) 增加，而归一化的 KNO 质量的光解速率则呈现相反的趋势。R 随辐照度 (88-262 W/m) 和相对湿度 (7-70%) 的增加而线性增加，而随 pH 值 (pH = 2-12) 的降低而线性增加。此外，根据实验结果提出了在 HA 存在下硝酸盐光解生成 HONO 的反应途径。最后，讨论了在 HA 存在下硝酸盐光解生成 HONO 增强的大气影响。
