Question

Compare SFC with other column chromatographic methods.

Short answer

Supercritical fluid chromatography or SFC is a type of normal phase chromatography that uses carbon dioxide as its mobile phase.

Step-by-step solution

Step 1

Due to the similarities between some physical properties of supercritical fluid and gas and liquid chromatography, the supercritical fluid chromatography can be considered as the combination of some characters of gas and some of liquid chromatography. When the mobile phase is selected for supercritical fluid, there are high diffusion rates and lower viscosity is observed that results into faster process of superficial fluid chromatography, similiar to that of gas chromatography as compared to liquid chromatography.

Step 2

The longitudinal band spreading in GC chromatography is beacuse of its characteristics of high diffusion, which is not present in liquid chromatography. Supercritical fluid chromatography is faster than liquid chromatography as the supercritical fluid contains intermediate diffusivities and viscosities and it is following gas chromatography where less seperation zone is present.

There are some limitations of supercritical fluid chromatography such as complexity of process and cost of instrumentation over the benefits of it.

Therefore, supercritical fluid chromatography is faster and suitable as compared to gas and liquid chromatography.