Precolumn

The process of column chromatography is often employed in the study of chemistry. This method is used to purify a wide variety of individual chemical compounds from mixtures of the compounds. Column chromatography is also typically used for preparative applications on scales ranging from micrograms up to kilograms. One of the main advantages of column chromatography is the disposability of the stationary phase used in the process, as well as the relatively low cost of the process itself. This disposability property is responsible for preventing cross-contamination in the mixtures that pass through the process. Column chromatography is also great for preventing the degradation of the stationary phase due to recycling.

Column chromatography uses the classic preparative chromatography column—a glass tube with a diameter of five millimeters to fifty millimeters, with a height of five centimeters up to a meter. This glass tube features a tap and usually some kind of filter—typically a glass frit or a glass wool plug, which is used in the prevention of the loss of the stationary phase—right at the bottom. There are two methods used to prepare a column: the wet method and the dry method.

In the wet method, a slurry will be prepared from the effluent. This slurry contains the stationary phase powder, which is then carefully poured into the glass column. One must be careful to avoid air bubbles. A solution of the specific organic material should be pipetted on top of the stationary phase, which will then be topped with a layer of sand or with a cotton or glass wool.

For the dry method, the column will be filled with dry stationary phase powder, which will then be followed by adding the mobile phase.

This category contains scientific information on column chromatography, which is used to purify a wide variety of individual chemical compounds from mixtures of the compounds.