Characterization of water-soluble ion species in urban ambient particles.
Concentrations and distributions of water-soluble ion species contained in ambient particles were measured in a coastal urban area, Kaohsiung City, Taiwan. PM10 and PM2.5 samples were collected using a dichotomous sampler from November 1998 to April 1999 and were analyzed for water-soluble ion species with ion chromatography. On the average, ion species measured in this study accounted for 42.2% of the PM2.5 and 35.7% of the PM10. It was found that SO4(2-) , NO3-, and NH4+ dominated the identifiable components within both fine (PM2.5) and coarse (PM2.5-10) fractions, and occupied 90.0% and 80.6% of total dissolved ionic concentrations for PM2.5 and PM10. The secondary aerosol formed through the NOx/SO2 gas-to-particle conversion was estimated based on the oxidation ratio of sulfur and nitrogen (SOR and NOR, respectively), i.e., sulfate sulfur/nitrate nitrogen to total sulfur/total nitrogen. The average SOR/NOR values were 0.25/0.07 and 0.29/0.12 for PM25 and PM10, respectively. The high SOR and NOR values obtained in this study suggested that there existed a secondary formation of SO4(2-) from SO2 along with NO3- from NOx in the atmosphere.
Lin
Jim Juimin
JJ
Department of Safety, Health, and Environmental Engineering, National Kaohsiung First University of Science and Technology, Yanchau, Taiwan, ROC. envelin@ccms.nkfust.edu.tw
D000393:Air Pollutants / Q000032:analysis* / Q000737:chemistry; D002852:Chromatography, Ion Exchange; D002947:Cities; D007477:Ions / Q000032:analysis* / Q000737:chemistry; D010316:Particle Size; D012621:Seasons; D012995:Solubility; D013624:Taiwan
D000393:Air Pollutants; D007477:Ions