Rosenberg E, Hallama R A, Grasserbauer M
Institute of Analytical Chemistry, Vienna University of Technology, Austria.
Fresenius J Anal Chem. 2001 Nov;371(6):798-805. doi: 10.1007/s002160101069.
The development and operational evaluation of a calibration gas generator for the analysis of volatile or ganic compounds (VOC) in air is described. Details of the construction, as well as of the evaluation of the apparatus are presented here. The performance of the test gas generator is validated both by on-line GC analysis of the calibration gas produced and by off-line analysis of adsorptive samples taken from the generated calibration gas. Both, active and passive sampling have been used, and the results demonstrate the excellent accuracy and precision of the generated test gas atmosphere: For the 11 investigated organic compounds (aromatic and halogenated compounds), the found values were in most cases within 5% of the target value with a reproducibility of better than 3% RSD (as determined by the analysis of the sampled adsorbent tubes). Custom made adsorbent tubes were used for active and passive sampling and in both cases were analysed by thermal-desorption GC. Particularly the combination of passive sampling and thermodesorption-GC analysis offers significant advantages over the commonly used active sampling on activated charcoal, followed by CS2 desorption in terms of avoidance of hazardous solvents, potential for automation and improved detection limits. Both sampling techniques are capable for monitoring VOCs at concentrations and under conditions relevant for workplace monitoring.
本文描述了一种用于分析空气中挥发性有机化合物（VOC）的校准气体发生器的开发和运行评估。这里介绍了该装置的构造细节以及评估情况。通过对所产生校准气体的在线气相色谱分析和对从所产生校准气体中采集的吸附性样品的离线分析，验证了测试气体发生器的性能。同时采用了主动采样和被动采样，结果表明所产生的测试气体氛围具有出色的准确性和精密度：对于11种被研究的有机化合物（芳香族和卤代化合物），在大多数情况下，所测值在目标值的5%以内，重现性优于3%相对标准偏差（通过对采样的吸附管分析确定）。定制的吸附管用于主动采样和被动采样，两种情况下均通过热解吸气相色谱进行分析。特别是被动采样与热解吸 - 气相色谱分析相结合，与常用的在活性炭上进行主动采样、然后用二硫化碳解吸相比，在避免使用有害溶剂、自动化潜力和提高检测限方面具有显著优势。两种采样技术都能够在与工作场所监测相关的浓度和条件下监测挥发性有机化合物。
