VACUUM BACKFLUSH RECYCLE SYSTEM FOR GC ANALYSIS OF HIGH-PURITY SOLVENTS

An operationally unique GC system is described which combines a high-precision, cryofocusing injector with a vacuum operated backflush device and a relatively short capillary column. The flow direction through both the cryoinjector and the column can be changed with a temporal precision of a few ms. Sample components that have not eluted can be returned quantitatively to the injector or they can be vented from the flow stream. The system is used here for solvent flush procedures which allow the recovery of peaks obscured by a large, broadened solvent peak. The operation of the system is evaluated for the rapid determination of impurities in common organic solvents.