1. Chapter 9Column Chromatography

2. Column Chromatography (CC) • Column chromatography is a useful method for separation and purification of solids and liquid samples under 10 grams. • CC works on the same principle of TLC except that the sample solution flows down a column of silica gel or alumina filled with solvent. • A partition coefficient represents the efficiency of the column and is determined by the solubility of the solute in the two phases.

3. Column Chromatography (CC) • Only complete Part 1 (microscale) pp. 210-211, Ferrocene and Acetylferrocene. • Packing the Column • Make sure your column has a polyethylene frit. • Pour the silica gel (or alumina) into the column so it is 1/2 to 2/3 full. • Pour this silica gel into a 50 mL beaker and add 8 mL of hexane. • Clamp the column in a vertical position. • Add 2 mL of hexane to the column. • Stir the hexane silica gel mixture while pouring into the column. • Open the valve and drain the solvent. Do not let the solvent level get below the silica gel. • Repeat the last three steps until all of the silica gel is in the column. • Close the valve with some solvent remaining at the top of the column.

4. Follow the handout for further experimental steps and obtain the following: Weight of crude ferrocene and of crude acetylferrocene. Melting points of ferrocene and of acetylferrocene. Percent Recovery Column Chromatography (CC)

5. Comments • Acetylferrocene is toxic. Handle with care. • Hexane is flammable. Be aware of your surroundings. • It should be easy to follow this separation process as both compounds are colored.