SO2、NO2与针铁矿、赤铁矿、磁铁矿的非均相反应  

Heterogeneous reactions of SO2 and NO2 with goethite,hematite,and magnetite

作　　者：贾小红 王甫 任燕 李锐 顾文君 张欢欢 唐钰婧 彭超 唐明金 JIA Xiao-hong;WANG Fu;REN Yan;LI Rui;GU Wen-jun;ZHANG Huan-huan;TANG Yu-jing;PENG Chao;TANG Ming-jin(State Key Laboratory of Organic Geochemistry,Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization and Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,China;Longhua Center for Disease Control and Prevention of Shenzhen,Shenzhen 518109,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院广州地球化学研究所,有机地球化学国家重点实验室/广东省环境资源利用与保护重点实验室/粤港澳环境污染过程与控制联合实验室,广东广州510640 [2]深圳市龙华疾病预防控制中心,广东深圳518109 [3]中国科学院大学,北京100049

出　　处：《地球化学》2021年第1期88-97,共10页Geochimica

基　　金：国家重点基础研究发展计划(2018YFC0213901);国家自然科学基金(91644106);广东省省级科技计划项目(2017B030314057,2019B121205006)。

摘　　要：硫酸盐是大气颗粒物的重要组分,SO2与矿质颗粒物的非均相反应可能是硫酸盐和水溶性铁形成的重要途径之一,但目前对该反应途径的研究比较有限。本研究开展了不同相对湿度条件下SO2((7.14±0.29)μg/L)、NO2((5.13±0.21)μg/L)与针铁矿、磁铁矿、赤铁矿的非均相反应,定量分析了产物硫酸盐、硝酸盐以及水溶性铁的含量随反应时间的变化。结果表明,SO2与针铁矿反应24 h仍未达到饱和,平均反应摄取系数小于1×10^(−8),但其随着相对湿度增大而增大。当NO2和SO2共存时,SO2和针铁矿非均相反应24 h仍未达到饱和,相对于NO2与针铁矿反应,SO2的共存抑制了硝酸盐的生成;反应前24 h,SO2平均反应摄取系数小于1×10^(−8),非干态下相对湿度对SO2摄取系数无显著影响。SO2或SO2、NO2共存时与磁铁矿、赤铁矿的反应几乎无硫酸盐生成,仅在SO2与NO2共存时生成少量硝酸盐。此外,SO2与3种含铁矿物的非均相反应对Fe元素水溶性的促进作用非常有限。Sulfate is a major component of atmospheric aerosol particles.The heterogeneous reaction of SO2 with mineral particles may be an important pathway in the formation of sulfate and soluble iron;however,this pathway has not been fully understood.In this study,we investigated the heterogeneous reactions of SO2(7.14±0.29μg/L)and NO2((5.13±0.21)μg/L)with goethite,magnetite,and hematite at different relative humidity,particulate sulfate,nitrate,and soluble iron levels.The heterogeneous reaction was quantified as a function of reaction time.Goethite was only partly deactivated 24 h after reacting with SO2.The averageγ(SO2)for 24 h was lower than 1×10^(−8),while it increased with the relative humidity.Goethite was also partly deactivated after the reaction with SO2 and NO2 for 24 h,in which the nitrate yield increased with the reaction time.In addition,the existence of SO2 would suppress the heterogeneous reaction of NO2 with goethite,thereby decreasing the nitrate yield.The averageγ(SO2)for 24 h in this reaction was also lower than 1×10^(−8),and it exhibited no dependence on the relative humidity.For magnetite and hematite,there was no sulfate formation after reaction with SO2 or SO2 and NO2 for 24 h,and very limited nitrate was formed from the heterogeneous reaction with SO2 and NO2.The impacts of heterogeneous reactions of SO2 with hematite,magnetite,and goethite on iron solubility could be very limited.

关 键 词：SO2 NO2 含铁矿物 非均相反应 

分 类 号：P593[天文地球—地球化学] X513[天文地球—地质学]