Procedure Title: Whole Oil SARA (Saturate, Aromatic, Resins & Asphaltenes)
Instrumentation: Gravimetric column
Theory of Operation:
• The asphaltene fraction of the oil is separated and quantified, and then the saturate, aromatic and polar (NSO) fractions of a crude oil are separated through silica as the stationary phase and different solvents as the mobile phases.
• The maltene (deasphaltened oil) passes through the silica, the saturate fraction is eluted by n-heptane, then the aromatic fraction is eluted by toluene, and the resins are eluted by a chloroform/methanol mixture.
Analytical Procedure:
Topping and quantification of topping loss.
Asphaltene precipitation and quantification.
Gravity column separation to determine the weight % saturates, aromatics and NSOs.
Distribute the topping loss in (Step 1) to the appropriate fractions (a portion to the saturate and a portion to the aromatic) based on the relative abundances of saturate to aromatic components in the fractions less than n C10 as determined by gas chromatography.