In order to recover hydrogen from a hydrogen-rich gaseous effluent, a procedure is used that comprises: in a stage (a), bringing a hydrocarbon-rich gaseous effluent into contact with the upstream face of a hydrogen-selective membrane at a pressure P1; in a stage (b), bringing a flow containing one or more unsaturated compound(s) into contact with the downstream face of a membrane at a pressure P2, which is smaller than P1, in the presence of a catalyst, to hydrogenate at least a portion of the unsaturated compound(s) using at least a portion of the hydrogen that passes by permeation through the upstream face to the downstream face of the selective membrane; and in a stage (c), transporting a flow containing the hydrogenated compound(s) into stage (b).