CHROMATOGRAPHY

1. Gas Chromatography (GC)

1.1. Gas-Liquid Chromatography

1.1.1. Stationary phase: liquid adsorbed ot solid surface

1.1.2. Type of Equilibrium: partition between gas and liquid

1.2. Gas_solid

1.2.1. Stationary phase: Solid

1.2.2. Type of Equilibrium: Adsorption

2. Liquid Chromatography (LC)

2.1. Liquid-liquid or partition

2.1.1. Stationary phase: Liquid adsorbed to solid surface

2.1.2. Type of equlilibrium: Partition between immiscible liquids

2.2. Liquid-solid or adsorption

2.2.1. Stationary phase: Solid

2.2.2. Type of equilibrium: Adsorption

2.3. Ion exchange

2.3.1. Stationary phase: Ion-exchange resin

2.3.2. Type of equilibrium: Ion exchange

2.4. Size exclusion

2.4.1. Stationary phase: Liquid in interstices of polymeric solid

2.4.2. Type of equilibrium: Partition

2.5. Affinity

2.5.1. Stationary phase: Group specific liquid bonded to solid surface

2.5.2. Type of equilibrium: Partition between surface liquid and mobile liquid

3. Supercritical fluid chromatography (SFC; mobile phase: supercritical fluid)

3.1. Stationary phase: Organic species bonded to solid surface

3.2. Type of equilibrium: Partition between supercritical fluid and bonded surface

4. Important factors

4.1. Distribution constant: Equilibrium constant for distribution of species between 2 phases (Kc)

4.2. Retention time: Time required to reach detector after sample injection (tR)

4.3. Retention factor: Compares migration rates of solutes in column

4.4. Selectivity factors: Ratio of distribution constants for strongly retained species to less strongly held species

4.5. Band broadening and column efficiency

4.5.1. Rate theory

4.5.2. Plate theory