Patent ID: 7211706

Claim:
A continuous process for recovering hydrogen from a hydrocarbon-rich gaseous effluent, comprising: a stage (a) in which a hydrocarbon-rich gaseous effluent containing hydrogen is brought into contact with the upstream face of a hydrogen-selective membrane at a pressure P 1 said hydrocarbon-rich gaseous effluent being a dry-gas fraction obtained from a process that is selected from the group consisting of fluidized-bed catalytic cracking, steam reforming, catalytic reforming, gasification, partial oxidation, and an autothermal process, that combines reforming and partial oxidation, coking, and visbreaking; a stage (b) in which a flow that contains one or more unsaturated compound(s) is brought into contact with the downstream face of said membrane at a pressure P 2 , which is smaller than P 1 , and in the presence of a catalyst, in such a way as to hydrogenate at least a portion of said unsaturated compound(s) using at least a portion of the hydrogen that passes by permeation through said upstream face to said downstream face of said selective membrane; and a stage (c) in which the flow containing the hydrogenated compound(s) in stage (b) is transported away from said downstream face.