Patent ID: 6986802

Claim:
A process using perm-selective membranes for simultaneous recovery of a permeate product and a desired non-permeate product from a fluid mixture of compounds, which process comprises: (1-a) providing a feedstream comprising a mixture of two or more compounds which when subjected to appropriately altered conditions of temperature and/or pressure exhibit a bubble point; (1-b) providing apparatus comprising means for controlling enthalpy of selected fluids within the apparatus and one or more membrane modules each including first and second zones separated by a solid perm-selective membrane which under a suitable differential of a driving force exhibits a permeability of at least 0.1 Barrer for one of the compounds of the feedstock, each first zone having at least one inlet and outlet for flow of fluid in contact with the membrane, and contiguous with the opposite side thereof a second zone having at least one outlet for flow of permeate; (1-c) introducing the feedstream into the first zone of one or more of the modules under conditions suitable for permeation, and thereby obtaining permeate and non-permeate streams from the modules; and (1-d) controlling enthalpy to maintain the Membrane Efficiency Index of the non-permeate fluid within a range from about 0.5 to about 1.5.