无机盐添加剂对蚊香燃烧产物中多环芳烃分布规律的影响

研究了3种无机盐添加剂(NaCl、Na2CO3和CaCO3)对蚊香燃烧烟气和灰烬中多环芳烃(PAHs)分布规律的影响,采用GC-MS方法分析样品中16种优控PAHs的含量.结果表明,未加添加剂时蚊香烟气中16种PAHs均有检出,其中萘最大(3.109μg.g-1),其次为菲(1.230μg.g-1)、二氢苊(0.495μg.g-1)和荧蒽(0.311μg.g-1),以2～3环PAHs为主,约占PAHs总排放因子的86.0%;灰烬中也以2～3环PAHs为主,但排放总量仅为烟气中的4.7%.添加NaCl和Na2CO3未能起到降低烟气中PAHs排放的作用,甚至导致烟气中PAHs总排放因子和毒性当量出现不同程度增加.比较而言,CaCO3降低蚊香烟气中PAHs排放的效果最佳.随着CaCO3添加量的增加,2～3环PAHs在烟气与灰烬中份额的比值明显增加,而5～6环PAHs在烟气与灰烬中份额的比值明显减少.摩尔分数为2.0%的CaCO3在降低蚊香烟气中PAHs总排放因子和毒性当量方面作用最显著,其PAHs总排放因子较未加添加剂时降低了1.8%,毒性当量浓度降低了86.6%.

Influence of Inorganic Additives on the Distribution of Polycyclic Aromatic Hydrocarbons in the Smoke and Ash from Mosquito Coils Burning

The influence of inorganic additives (NaCl, Na2CO3 and CaCO3) on the distribution of polycyclic aromatic hydrocarbons (PAHs) in the smoke and ash from mosquito coils burning was studied, GC-MS technique was applied to analyze the contents of 16 priority-controlled PAHs recommended by US EPA. The results show that 16 priority-controlled PAHs are detected in the smoke of mosquito coil without additives, characterized by the predominance of 2- to 3-ring PAHs, which are ranked as NaP (3.109 microg x g(-1)) > Phe (1.230 microg x g(-1)) > AcP (0.495 microg x g(-1)) > FluA (0.311 microg x g(-1)); the emission factors in the ash are also predominated by 2- to 3-ring PAHs, but the total PAHs emission factors in the ash are only 4.7% of those in the smoke. NaCl and Na2CO3 additives can not decrease the emission of PAHs but promote total emission factors and TEQ of PAHs in the smoke of mosquito coils increase remarkably. The best additive in this study is CaCO3. With the increase of the addition of CaCO3, the proportion for 2- to 3-ring PAHs in the smoke increases remarkably than that in the ash, while the status reverse for 5- to 6-ring PAHs. CaCO3 with mole fraction of 2.0% has the most excellent property to decrease total emission factors and TEQ of PAHs in the smoke of mosquito coils, and the total emission factors and TEQ of PAHs decrease 1.8% and 86.6% respectively compared with the control.