Membrane separation of hydrocarbons

DETAILED DESCRIPTION OF THE INVENTION As was previously discussed, the present invention relates to a process for the separation of liquids of disparate molecular weight utilizing, as a means for separation, a membrane.
The means of separation will be particularly applicable in processes such as the treating of emulsions whereby heavy oil emulsions are broken by the means of a solvent, in food processing whereby edible oils are extracted utilizing as the extractive agent a solvent, in the preparation of synthetic fuels as exemplified by the dilution of shale oil with a solvent whereby insoluble particles may be recovered by filtration, in coal liquefaction in which a solvent is utilized to facilitate the filtration of insoluble particles, or in the treatment of wood chips utilizing a solvent such as ethanol to dissolve the cellulosic material.
It is to be understood that these various processes are merely given as examples of processes in which a membrane may be employed to effect the desired separation.
The separation of heavy oils from relatively light hydrocarbons which have been used as solvents in the various processes is effected by passing a mixture of heavy oils and light hydrocarbons over a membrane whereby a separation is effected and the light hydrocarbons are recovered as the permeate while the heavy oils are recovered as the retentate.
The membrane which is employed to effect the desired separation will comprise an organic polymer which will maintain its integrity in the presence of hydrocarbon compounds at the particular separation conditions which are utilized to effect the desired separation.
The particular organic polymer which is used should possess certain desirable characteristics with regard to stability under process conditions.
For example, the polymeric material should undergo no volume change while being maintained at a temperature of 50.
degree.
C.
for an extended period of use which may range up to a time of one year or more; a chemical stability as evidenced by the polymer undergoing no dissolution swelling or plasticizing when subjected to the action of a solvent at a temperature of about 50