In the chromatographic separation process, a solvent is allowed to flow down the column in two ways, one by gravitational force and other with the help of positive air pressure. When air pressure is used for separating and purifying the components from the mixture, that process is called as flash chromatography. The smaller particles with higher mesh sizes of silica gel are used for such type of chromatography. This process is commonly used for the rapid separation where small particles of silica gel are used for the high resolution chromatography. To pass the solvent through the column of stationary phase, pressurized gas is used to make the flow gently without any restriction.

Flash chromatography is preferred for various applications due to its quicker separating ability and more reproducible as compared to traditional column chromatography. The remaining solvent can easily be flushed out of the column with the help of pressurized gas. It is an effective technique that works efficiently and quickly in improving the purity of samples to the desired level. It helps in getting the pure compound by separating it from the solvent. The solvent with high polarity has the power to increase the elution speed of the desired compound. The quantity of silica gel needs to be considered when using chromatographic separation process.