Real-time gas chromatography-mass spectrometry trace gas detection

摘要

A gas flow distribution system accumulates a sample from a sample bearing carrier gas in a micro-accumulator, delivers it using a carrier gas to a gas chromatography column, and supplies a carrier gas to the gas chromatography column to facilitate separation of the sample into sample components and transport the sample components to a mass spectrometer for trace vapor detection and analysis or testing in real time. The system is made of inert components and configured to have low dead volume for improved performance and accuracy of detection. External valves are employed for easy management and balance of the flow in the system to minimize operation time and facilitate continuous accumulation, delivery, and testing of the sample. The delivery of the sample to the gas chromatography column using an electrically heated cold trap as the micro-accumulator can be performed extremely fast. By further combining the sample accumulation phase and the sample testing phase, real time operation of trace vapor detection is achieved. Because the step of delivering the sample to the gas chromatography column is performed quickly, the accumulation of the sample can resume quickly and is nearly continuous for improved efficiency.