Abstract:
Coal burning emission is one of the major sources of the airborne particles in northern China. In this paper, the trace elements in coal-burning derived inhalable particulate matters( PM10 ) collected from a combustion-dilution system in laboratory were studied by the ICP-MS(Inductively coupled plasma mass spectrometry). The raw coals were collected from the coal mines of Zhijin,Datong,Dongsheng,Yinchuan,and Jingxi areas. The results indicate that Zn, Fe,Rb,Pb,Cu,Cr,Ti,Mn,Ba,Ni,As are enriched,in descending order,in the whole sample of coal-burning derived PM10 ,and the water-soluble trace elements are mainly Zn,Rb,Pb,Cu,Ti,As,Ni in descending order of contents in PM10 . The percentages of the water-soluble Cs,Rb,Cd,Tl,Sb,Zn in the total individual trace elements are relatively high,which indicate that these elements exist mostly as water-soluble state in coal-burning derived PM10 . Interestingly, Fe is not detected in the water-soluble fraction of PM10 ,indicating that Fe existed mainly as insoluble state in the coal- burning derived PM10 . The rare earth elements in PM10 emitted from coal burning are dominated by Sc,Ce,Nd and La. The contents of the total analyzed trace elements( TATE) are highest in the PM10 emitted fromburning the Yin- chuan coal,followed by the PM10 s from burning the Zhijin,Jingxi,Datong,and Dongsheng coals in descending order.The higher levels of the TATE in PM10 emitted from burning the Yinchuan and Jingxi coals are due to the high ash contents in the raw coals,and the higher levels of TATE in the PM10 emitted from burning the Zhijin coal are attributed to the high sulfur content in the raw coal.