I used a gas-solid chromatograph to analyse air from underground coal mines. This detects whether methane is accumulating to a dangerous level but mostly it detects very low concentrations of carbon monoxide which can indicate that spontaneous combustion of coal is beginning.
The same instrument can be used in analysis of the air above the oil in oil-cooled electrical transformers. This can detect whether water has entered the machine which can lead to blackouts because the transformer short circuits on the water and blows up.
These instruments detect and measure hydrogen, carbon dioxide, ethylene, ethane, oxygen, nitrogen, methane and carbon monoxide in that order.
Chemists in oil refineries use a more elaborate version of the same kind of instrument to analyse for extra gases.
Very few gas or liguid chromatographs use silica as a solid phase. It is mainly, perhaps only used in thin layer chromatography for a quick and dirty separation of a few substances.
Some solid phases used for gas analysis include Molecular Sieve 5A which is a porous mineral with a high silica content. Porapak N and Q are porous plastics, polystyrene if I recall correctly.
You can even use charcoal for some work.
Gas-liquid and liquid chromatographs use a solid phase on which some very viscous liquid material is adsorbed. The liquid may be a polyethylene oxide with an average molecular weight of 500 or more, or sometimes silicone oils are used. These are just two of a very wide range of materials available.
These sorts of instruments can be used to detect and measure most of the components of gasoline, kerosene, vegetable oils, butter fats, sugar syrups and a host of other mixtures of similar substances.
If police or fire are suspicious that a fire might have been deliberately lit, they can take air samples from a burnt building and run then through a gas chromatograph which will determine if much gasoline, kerosene or flammable solvent has been used and what the flammable liquid was.
Another form of chromatography separated the bases of DNA for the human and other genome projects and yet another that uses an electric field instead of a flowing gas or liquid is used to separate the amino acids of proteins when they are being analysed for their sequence.
This is also a great website!
http://www.buzzle.com/articles/chromatography-uses.html"Uses of Chromatography
Chromatography has evolved to be one of the most widely used chemical techniques to separate particles and contaminates in chemical plants. For example, in the chemical industries, pesticides and insecticides like DDT in the groundwater and PCBs (Polychlorinated biphenyls) are removed by the process of chromatography. As a major testing tool, chromatography is used by government agencies to separate toxic materials from the drinking water and also to monitor air quality.
One of the significant chromatography uses is made in pharmaceutical companies, who specialize in making medicines. Chromatography is used by pharmaceutical companies to prepare large amounts of pure materials that are further required in making medicines. Also, it is used to check the presence of any contamination in the manufactured compounds.
In the field of organic chemistry and pharmacy, chiral compounds are very close to each other in terms of atomic or molecular weight, element composition, and the physical properties. However, they exist in two different forms, called as the enantiomers and optical isomers. Both these compounds though may appear to be same, have very different chemical properties. So, in pharmacy, chromatography becomes crucial to analyze the exact chiral compound so that correct medicines can be manufactured. For instance, a compound called as thalidomide has two optical isomers and one of the isomers can cause birth defect if a pregnant women consumes it in early stages of pregnancy. So, it is important to carefully separate the isomers.
Other important chromatography uses are in the food industry where proper food maintenance is necessary to ensure quality. Chromatography is used as a technique to separate the additives, vitamins, preservatives, proteins and amino acids. Some other chromatography uses are in the detection of drugs or medications in the urine and the separation of traces of chemicals in the case of fire in houses or buildings. It is also very popular in forensic science for investigative purposes.
Chromatography technology has gained immense industrial popularity in the past few decades as it can separate chemicals that just differ even in their atomic orientations in space. These were some of the chromatography uses that are used in various technological pursuits in chemical industries."
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