摘要 |
<p>A continuous fractionation technique is provided for recovering ethylene from an olefinic feedstock comprising C3+ higher olefins. This technique provides methods and means for contacting the olefinic feedstock in a counter current sorption tower with a liquid sorbent stream comprising C6+ gasoline range hydrocarbons under process conditions to selectively sorb substantially the entire C3+ olefin components from the feedstock, withdrawing an ethylene-rich vapor stream from the sorption tower and further contacting the ethylene-rich stream with a distillate range liquid hydrocarbon stream in a sponge absorber to purify the ethylene stream. Typically, the olefinic feedstock consists essentially of volatile hydrocarbons, and preferably comprises about 10 to 50 mole % ethylene and 10 to 50 mole % propene. Purified ethylene product may be recovered having an average molecular weight not greater than 28.5 under non-cryogenic conditions.</p> |