杭州市大气细颗粒物中铁溶解度的变化特征及影响因素

Variation and influencing factors of iron solubility in fine particulate matter in Hangzhou

采集了杭州市污染天和非污染天的PM_(2.5)样品,并进一步获取了PM_(2.5)中可溶铁(FeS)的浓度及%FeS.研究结果显示,采样期间气溶胶中总Fe(FeT)的浓度为(629±296)ng/m^(3)(150~1167ng/m^(3)),FeS的浓度为(51.4±30.5)ng/m^(3)(4.2~90.5ng/m^(3)),%FeS为(7.8%±3.5%)(1.5%~12.9%).污染天PM_(2.5)、FeT和FeS的浓度均明显高于非污染天,且污染天%FeS为9.3%,高于非污染天的5.1%.本研究发现%FeS的差异主要与Fe的来源和大气酸化过程相关,污染天Fe受交通排放和工业排放等人为源的影响更大,且污染天大气酸化程度更强.

In this study,PM_(2.5)samples were collected during polluted and non-polluted days in Hangzhou.The mass concentrations of soluble iron(FeS)and the Fe solubility(Fes%)in the PM_(2.5)were analyzed.The results show that the total Fe(FeT)concentration was 629±296ng m^(3)with the range of 150~1167ng m^(3),soluble iron concentration was 51.4±30.5ng m^(3)with the range of 4.2~90.5ng m^(3),and the Fe solubility is 7.8±3.5%with the range of 1.5~12.9%.The concentrations of PM_(2.5),total Fe and soluble iron in polluted days were significantly higher than those in non-polluted days.Fe solubility was 9.3%in polluted days,much higher than 5.1%in non-polluted days.This study found that the difference of Fe solubility is mainly related to the source of Fe and the process of atmospheric acidification.Fe in polluted days is mainly affected by anthropogenic sources such as traffic and industrial emissions,and the atmospheric acidification in polluted days is stronger.