武汉市科教区冬春季PM_(10)和PM_(2.5)质量浓度及水溶性离子分析

2006～2007年冬春季在武汉市湖北大学校区连续采集气溶胶样品,并用离子色谱分析了气溶胶中水溶性无机成分的含量。结果表明,PM2.5和PM10中总水溶性无机离子年平均浓度分别为3.98和6.79μg/m3,其中4种主要的水溶性无机离子Na+、Ca2+、SO42-和NO3-,共占PM2.5和PM10总水溶性离子浓度的79%、85%。Mg2+、Ca2+、F-、SO42-、Na+和Cl-主要集中在细粒子中,NH4+和NO3-主要集中在粗粒子中。NH4+和SO24-在PM2.5和PM10中的相关系数R=0.987、0.983,主要以NH4NO3、(NH4)2SO4和NH4HSO4的方式存在。离子来源分析显示,固定排放源(燃煤)对水溶性组分的贡献要高于移动排放源(机动车)的污染贡献,而局地二次扬尘及建筑扬尘也是大气细粒子中水溶性组分的一个重要来源。

Analysis of Mass Concentration and Water-soluble Ions in PM_(10) and PM_(2.5) in the Winter and Spring in Wuhan Sci-tech Teaching Area

The aerosol samples were collected in Hubei University during winter-spring time (from November of 2006 to April of 2007) and soluble ions in PM_(2.5) and PM_(10) were analyzed by ion chromatogram(IC) . The results showed that the annual concentrations of total water soluble inorganic ions were respectively 3.98 and 6.79 μg/m~3, four major ions of Na~+, Ca~(2+) , SO_4~(2-) and NO_3~-, accounted for respectively 79% and 85% in PM_(2.5) and PM_(10) . Mg~(2+), Ca~(2+), F-, SO_4~(2-), Na~+ and Cl~- were mostly distributed in fine particles , and NH_4~+ and NO_3~- were mostly distributed in crude particles. The correlation coefficient R of NH_4~+ and SO_4~(2-) were respectively 0.987 and 0.983 in PM_(2.5) and PM_(10),main existence form of NH_4~+ and SO_4~(2-) were NH_4NO_3, (NH_4)_2SO_4 and NH_4HSO_4. Source analysis of ions showed that fixed emission sources (coal) on the contribution of water-soluble components were higher than that of mobile emission sources (motor vehicles) contribute to the pollution. The local secondary dust and construction dust was an important source of water-soluble components in fine particles.