| abstract |
A continuous process for selective countercurrent extraction of C2+ hydrocarbons from a gas stream with a lean oil as solvent is rejuvenated by substitution of a preferential physical solvent for the lean oil solvent to produce a residue gas stream meeting specifications for methane content and a hydrocarbon product having a composition which can be adjusted to a selected minimum degree for ethane that is as low as 2% ethane and produce at the maximum propane content that is available from the equipment, whereby profitability of the extraction operation can be maximized at all times. The preferential physical solvent has a minimum relative volatility of methane over ethane of at least 6.0 and a solubility of at least 1.0 standard cubic foot of gaseous hydrocarbons per gallon of the solvent (thereby defining its hydrocarbon loading capacity) or, alternatively, a preferential factor of at least 6.0. Preferred solvents include polyalkylene ethers of dialkylene glycol and alkyl-substituted monocyclic C8-C10 aromatic hydrocarbons, preferably including mesitylene, reformates, crackates, and mixed xylenes. |