Purer gases cut costs
15 Jan 2000
Companies using chromatography gases could find that a new innovation from Air Products will help cut their costs and improve the accuracy of their analyses. The BIP - built-in purifier - ensures that the gases supplied are of high purity.
Gas chromatography (GC) uses an inert carrier gas - generally nitrogen or helium - to sweep samples of gas or liquid mixtures through a long, narrow separation column inside an oven. The purity of the carrier gas is of the utmost importance, as impure gases can create `ghost peaks' on the final analysis chart, and can also damage the chromatography column itself. Normally, a `purification train' between the gas cylinder and the GC machine ensures the purity, but these systems are unreliable as they cannot be monitored.
The BIP system replaces the external train with an internal system, attached to the cylinder valve. The gas is drawn through a sintered plug in the base of the BIP tube (see picture) and passes through a series of filtering materials. Air Products guarantees oxygen levels of less than 10ppb and moisture below 20ppb - better than the purest gases currently available.
BIP gases can stretch the lifetime of a GC column fourfold, according to pilot studies. This represents savings of time as well as money.
