Abstract Counter-current deasphalting is a key unit operation in the Dow Liquefaction Process. The Dow developed deasphalter removes typically 99.8–99.9% of the ash and 94–95% of the toluene insoluble hydrocarbons from the coal liquefaction product. The deasphalted oil, after separation from solvent, contains less than 0.05% ash. Deasphalted coal liquefaction product, a low sulfur, low residue, premium synthetic oil, constitutes 40% of the net liquefaction products. The deasphalter residue typically contains 40% ash and up to 25% hydrocarbonaceous coal solids. It has a heating value of approximately 9000 BTU/1b and is produced as a viscous pumpable fluid. These properties are important in the Dow Process where deasphalter residue is gasified to generate the hydrogen for the liquefaction step. The solvent used in the deasphalter is a paraffinic 50–75° light oil cut from the liquefaction unit. The counter-current deasphalting technology is based on the results from model and batch studies and results from t...