Choice of the eluent (mobile phase)
The eluent consists of a solvent or a mixture of solvents. In the latter case the solvents must then be MISCIBLE. Often the mixture consists of a polar solvent and an apolar solvent.
The choice of the eluent is adjusted according to the polarity of the compounds to be separated.
- Petroleum ether / diethyl ether
- Cyclohexane / ethyl acetate
- Dichloromethane / ethanol
The choice is made according to the compounds to be analyzed:
- Aliphatic ketones: toluene / diethyl ether
- Aromatic carbonyls: hexane / ethyl acetate
- Alcohols: petroleum ether / diethyl ether / ethanoic acid (90/9/1)
Click on each box to see the examples.