大气可吸入颗粒物(PM10)中矿物组分的X射线衍射研究

利用X射线衍射技术对北京2002春季和夏季的可吸入颗粒物进行了研究.结果表明,北京春季和夏季可吸入颗粒物的矿物组成明显不同,春季可吸入颗粒物中的矿物以硅铝酸盐为主,同时存在碳酸盐、硫酸盐、硫化物、铁的氧化物、粘土矿物以及难以鉴定的矿物;在夏季的样品中,矿物的种类有所减少,却有新的物种出现,如氯化氨、硫酸氨等.XRD定量分析显示,在沙尘天气时,可吸入颗粒物中石英和粘土矿物以及非晶质分别占到24.1%、28.5%和2 0%,斜长石和方解石分别占到10.4%和8.1%,其他矿物总共不到10%.矿物组分的确定对可吸入颗粒物来源的识别有一定的指导作用.

XRD analysis of mineral compositions in inhalable particulate matter (PM10)

The PM_10 samples from Beijing air in spring and autumn 2002 were analyzed using X-ray diffraction (XRD). The results indicated that mineral compositions of PM10 in spring and autumn were very different. In spring,minerals in PM10 were predominated by aluminosilicates,with a small quantity of carbonates,sulphates,sulfides,iron oxides,clay minerals and unidentified minerals. The species of minerals detected in the summer collections were relatively limited. However,some new crystals like NH4Cl and (NH4)2SO4 were found in summer samples,suggesting that the atmospheric chemical reaction is more active in summer than in spring. Semi-quantitative analysis of minerals in PM10 of the dust storm indicated that quartz,clay minerals,plagioclase,calcite and non-crystalline materials accounted 24.1%,28.5%,10.4%,8.1% and 20%,respectively,with the others accounting for less than 10%. Identification of minerals in PM10 could be used to explain the source of particulate matters.