新型动态针捕集阱技术分析大气中低浓度的VOCs

本研究针对大气中挥发性有机物（VOCs）浓度低,难于分析等特点,以Carboxen 1000作为吸附剂,制作一种新型动态针捕集阱（needle trap）装置,可用于主动富集大气中低浓度VOCs.该装置与气相色谱-质谱（GC-MS）联用,操作简单、无需溶剂、容易定性定量.选择空气中苯系物（BTEX）为目标化合物,对needle trap装置从设计原理到实际应用进行了详细分析,将萃取条件与穿透体积等实验条件进行优化,建立了needle trap吸附提取空气中BTEX的最佳条件.结果表明,方法检出限低至0.05ng·mL-1,加标回收率为86.5%～110.5%,符合外场采样要求.

Determ Ination of Low Concentration VOCs in Air by a Newly Designed Needle Trap Device

Targeting on the problem of atmospheric VOCs that are presenting low concentration and difficult for sampling, a newly designed needle trap device with carboxen 1000 as a sorbent material was developed. The main advantages of needle trap device are the simple methodology,the easiness and the rapidity of the analysis coupling with GC-MS. No solvent was used in all experiments. Volatile analytes benzene, toluene, ethylbenzene and xylenes (BTEX) were chosen as target compounds to validate this device from theory to real application. The experimental parameters as breakthrough volume of stripping gas were investigated. LOD ranges was obtained at 0.05 ng·mL ^-1, and the standard recovery was from 86.5% to 110.5% respectively. Needle trap device is suitable for sampling in field.