采用DNPH-HPLC-UV分析方法,研究了2006年广州夏季空气污染较严重日17种挥发性醛酮类化合物的污染特征及其初步来源.结果表明,广州大气中主要的醛酮类污染物是丙酮、甲醛、2-丁酮和乙醛,其日均浓度分别为10.84、9.29、8.35和8.0μg.m-3,占总醛酮类化合物日均浓度的72.29%.城区省站测点总醛酮类化合物日均浓度最高,达到59.66μg.m-3,而郊区从化测点的总醛酮类化合物日均浓度最低,为43.51μg.m-3.各种化合物在不同垂直高度的采样点表现出不一致的浓度变化规律,而在水平方向上均表现出昼间明显高于夜间的日变化规律.大气中甲醛、乙醛和丙酮相关性好,具有较好的同源特征,而C1/C2、C2/C3比值分别为1.12、7.51,反映出机动车尾气排放对大气醛酮类化合物具有相当重要的贡献.
Characterizations and their primary sources of 17 carbonyls compounds in the serious air polluted summer-days of 2006 were studied by DNPH-HPLC-UV measurement methods. Results were shown as follows, acetone was found to be the most predominant carbenyls followed by formaldehyde, 2-butone and acetaldehyde, with the 24 h average concentrations of 10.84, 9.29, 8.35, 8.0 μg· m-3 respectively, which accounted for 72.29 % of total carbonyl compounds in the atmosphere. Among the four sites, the highest level of total carbonyl compounds was 59.66μg· m-3 at the urban site of Guangdong Provincial Centre of Environmental Monitor, the lowest was 43.51 μg· m-3 at the rural site of Conghua. Different variation characterizations of each carbonyl compounds at there different height sites were found, and the diurnal variation was shown that the total concentration of carbonyl compounds in daytime was much higher than that of nighttime. Good correlations between formaldehyde, acetaldehyde and acetone indicated that they mainly derived from the same sources, and the value that C1/C2 and C2/C3 ratios were 1.12 and 7.51 respectively implied that the important pollution sources of carbonyl compounds was vehicular exhaust in Guangzhou.