Improved On-Column Injection System and Large Volume Needle Trap Device Used in Water Headspace Analysis

摘要

An improvement of the on-column injection system for the use of large diameter inside needle capillary adsorption trap devices is presented. A modified glass liner in combination with a gas tight glass fitting, used in the conventional split/splitless gas chromatographic inlet, enables to keep impurities desorbing from the outside of the needle trap and septum from being injected into the analytical GC column. The performance of the system was verified by headspace analysis of model and real water samples for benzene, toluene, ethylbenzene and xylenes. The analytical method shows good linearity, repeatability, sensitivity and advantages such as simplicity, low cost and feasibility.