Top Factors To Be Considered During Gas Charomatography

It is an accepted fact that when it comes to Gas Chromatography, there is still a dire need to remove particular gases before we use any pure gas in gas chromatography. The major impure gases that are posed to create problems in gas chromatography are:-

•       Oxygen
•      Carbon Dioxide
•      Moisture
•      Few Hydrocarbons

The presence of these gases creates considerable problems in gas chromatography analysis and should be used in pure form, free on any contaminated gases. The presence of hydrocarbons creates a baseline noise, leading to wrong results where as oxygen and moisture cause excessive bleed and strip phase, damaging the gas chromatographic column and shortening the life span of the column.

Process of Gas Purification

A good purification gas system is designed to remove all carbon dioxide, moisture, oxygen, oil, hydrocarbons and other impurities from the gas streams that are used in the process. The system should be capable of eliminating all unacceptable noises and signals of such gases and any other impurities to achieve resolution, achieve peak tailing in gas analysis.

The carrier gas will pass through several filters to remove moisture and oxygen in the primary stage. In second stage, the carrier gas passes through filters to remove any hydrocarbons and other impurities. The gas steams are generally controlled by a regulator to ensure constant pressure. The purification system has a gauge that displays the inlet pressures as well as outlet pressure.

Construction of Systems of Purification of Gas

Most of the systems that are involved in gas purification are wall mounted, compact and powder coated.  They make sure that the delivery of ultra high pure grade gases is uniform throughout. The filters of such systems are easily detachable and are designed to handle an inlet pressure of 10kg/cm2 and the outlet pressure of 7kg/m2. The tubing of such purification systems is ¼ inches or 1/8 inches while there are some systems available that have tubing of ½ inches as well.

The purification panel for purifying gas in gas chromatography is applicable for TCD, FID, ICP, ECD, AAS, and MS. Usually such systems come with wall mountable feature but they can also be mounted on bench where either space is unavailable or such an application is necessary.

Benefits of Purification of Gas

The gas purification process in gas chromatography improves the reproducibility of analysis. The process also reduces the baseline noises along with other drift problems. The purification mechanism increases the column life especially for the polar columns and capillary. Further the purification process ensures that the delivery is made through better than ultra high pure grade gases. This reduces the problems of fire and flames and increases the life of gas detector as well. The end result of such processes is savior of costly gases through designed gas distribution pane and toggle valves.

Simply put, a good gas purification system will eliminate oxygen, carbon dioxide and moisture from industrial gases used in gas chromatography. The gases used in the process include toxic, lighting, pharmaceutical, special, isotopic, hydrocarbon, and inert.