Normally, the materials used for making the
packed column tube are stainless steel tube, copper tube, aluminum tube, nickel plated brass tube, glass tube, polytetrafluoroethylene tube, etc. As copper tube and aluminum tube have strong catalytic activity and are easy to deform, they have been less commonly used now.
The inner diameter of the packed column which is for analysis is ordinarily 2 to 4 mm, while that for sample preparation is 5 to 10 mm. The shape of the column could be spiral or U-shape, and you can get higher column efficiency by using the latter one.
The material selection of the
packed column should be decided by the sample’s character and the experiment condition. If the sample is labile or corrosive, you should use a glass tube or polytetrafluoroethylene tube. The advantages of the glass tube are good chemical inertness, high column efficiency and easy to observe. But the disadvantage is frangibility.
On the other hand, the advantage of the polytetrafluoroethylene tube is corrosion resistance, while the disadvantage does not bear high temperature and pressure. Currently, the stainless steel tube is mostly used for the
packed column. The advantages of stainless steel tube are unbreakable, good heat transfer property and long service life. The disadvantages are activated and hard to clean.
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