Method of treating sour liquefied petroleum gas

A method of removing hydrogen sulfide from sour liquefied petroleum gas comprising:

• (a) contacting the sour liquefied petroleum gas in an extraction column with a liquid and regenerable absorbent to obtain sweet liquefied petroleum gas which contains contaminants;
• (b) splitting the sweet liquefied petroleum gas which contains contaminants into a liquid bottom stream and a gaseous overhead stream;
• (c) supplying at least part of the liquid bottom stream to a first membrane unit comprising a membrane selected from a permselective membrane and a porous hydrophobic membrane, a permeate outlet and a retentate outlet;
• and
• (d) removing from the permeate outlet of the membrane unit sweet liquefied petroleum gas which is substantially free of contaminants and from the retentate outlet of the membrane unit sweet liquefied petroleum gas in which the contaminants are concentrated.

A method of removing hydrogen sulfide from sour liquefied petroleum gas comprising:

• (a) contacting the sour liquefied petroleum gas in an extraction column with a liquid and regenerable absorbent to obtain sweet liquefied petroleum gas which contains contaminants;
• (b) splitting the sweet liquefied petroleum gas which contains contaminants into a propane-rich overhead stream and a butane-rich bottom stream;
• (c) supplying at least part of the propane-rich overhead stream to a first membrane unit comprising a membrane selected from a permselective membrane and a porous hydrophobic membrane, a permeate outlet and a retentate outlet;
• (d) removing from the permeate outlet of the first membrane unit a treated propane-rich stream and from the retentate outlet of the first membrane unit a contaminated propane-rich stream;
• (e) supplying at least part of the butane-rich bottom stream to a second membrane unit comprising a membrane selected from a permselective membrane and a porous hydrophobic membrane, a permeate outlet and a retentate outlet;
• and
• (f) removing from the permeate outlet of the second membrane unit a treated butane-rich stream and from the retentate outlet of the second membrane unit a contaminated butane-rich stream.