Gas purifiers are essential because they assist in providing a clean gas stream, which can guarantee the grade of the gas chromatographic analysis and the reliability of the results. Further, such gas purifiers minimize detector noise and prolong the life of the column. Gas purifiers are like plans to protect the instrumentation and other analytical columns from various kinds of contaminants. Still, the gas purifiers will not be in a position to convert low purity gases into high purity gases. Due to this important factor, it is necessary to select the proper grade of gases with different purity levels for proper used in gas chromatographic applications.

Selection of Right Gas Purifier to fit your Applications

Various types of gas purifiers can be purchased in the market. Although some gas purifiers remove just one single specific contaminant, other styles remove multiple contaminants simultaneously from the gas stream. You will need to think about several factors during the selection procedure for gas purifiers, considering your specific applications. These factors will include the potential contaminants within the gas stream, the limitations on flow and pressure, levels of gas purity required, desired convenience in replacement of spent gas traps, and space availability.

Common Traps Used in Gas Purifiers

Oxygen, hydrocarbon, skin tightening and, and moisture traps are the most common purifiers found in most the gas chromatography (GC) applications. headspace sampler are usually filled with metal catalysts. Oxygen is considered as probably the most detrimental contaminating gas in every analytical columns. Oxygen is capable of producing irreversible oxidation damage, especially to polar stationary phases. Hydrocarbon traps are usually filled with activated charcoal, which can absorb organic compounds which are larger than methane. Still, the molecular weight and size of the organic contaminants will have a definite influence on the capability of the hydrocarbon trap to an excellent extent but it may also think about trap efficiency to some extent.

Activated charcoal possesses an increased capacity to trap larger hydrocarbons which are greater than C4, compared to smaller hydrocarbons, which are lesser than C4. Moisture traps are often filled with unique molecular sieves. When put through extensive heating, the crystalline structures are forced to reduce their hydration or water content. This opens a cavity which gets filled readily with any compound that can fit the cavity. Water fits perfectly into this cavity but this trap may also be in a position to remove gases like carbon dioxide, sulfur dioxide, hydrogen chloride, and chlorine or other gases which have effective diameters lesser than water.

Procedure for Contaminants Affecting Gas Stream

If you wish to understand how the contaminants affect the gas stream, you must follow the road that the carrier gas takes to get into the gas chromatograph. This path does apply for detector fuel gases also. The gases begin from a gas tank or a special gas generator. The gas travels through long lengths of tubes, pressure gauges, valves, and different other fittings. Each one of these areas is really a potential culprit to introduce contaminants in to the gas stream. This leads not merely in degrading the outcomes of chromatography but also shortens the life span of the column of CG.

Major contaminants like oxygen, hydrocarbons, and moisture can handle wreaking havoc with the columns and detectors of CG. The packed and capillary columns can get degraded easily if they are exposed to oxygen or moisture, especially at high temperatures. These contaminants may also compromise detector performance. Because the detectors actually ‘see’ these contaminants, the effect is baseline noises, spikes, and drifts.

It is advisable to install gas purifiers in a vertical position as wall mounted types to avoid channeling. Channeling occurs once you install the gas purifier in a horizontal position. Gas purifiers can be found as compact panels having multiple purifiers or single panel that has multi-absorbent capabilities.