一次热解吸直接进样浓缩方法的研究--室内大气中挥发性有机化合物的分析

研制了新型的一次热解吸直接进样热解析仪．考察了新型热解吸仪热解吸定量的重复性、准确性、热解析率、线性等性能．通过实际采样分析证明，该方法提高了浓缩倍数，操作简单，易于掌握，定量重复性好、准确度高，分析结果可靠．适合大批量样品的分析测试．

Study on the Enrichment Method by a One-step Thermal Desorption and Sample Direct Injection Technique for Analysis of Volatile Organic Compounds in Room Air

The analysis of Volatile Organic Compound(VOC) in room and outside air has been carried out widely among academic institutes,colleges,universities,as well as environment protection and health epidemic prevention system.The difficulty of this task consists in the complicated composition and small content of VOC in the air sample to analyze.Especially,the VOC in room air is very thin generally and can not be tested by gas chromatography without condensation.Therefore,the condensation method becomes the key of VOC gas chromatography.We developed a new one-time thermal desorption and direct sample injection thermal desorption instrument,and it has been put into practice largely.There are backflush unit and injection port in the instrument,through which desorption pipe can be conditioned and standard curve can be drawn easily.The thermal desorption pipe is equipped with gas path.Hot desorption pipe could be cooled to room temperature by opening the thermal desorption stove lid in just 4 to 5 minutes. The quantitative analysis performance of the instrument,such as repeatability, accuracy,thermal desorption ratio and linearity was tested.Practical sampling analysis has showed that it is a fine method due to high sample condensation multiple,simple operation,good repeatability,high accuracy and credible analysis result.It suits the test of samples in bulk.