Abstract: An installation for the separation of a gaseous mixture, particularly for the production of hydrogen, by pressure modulated adsorption, comprises at least one pair of adsorbers (I, II; III, IV) operating offset as to time according to a predetermined cycle comprising phases of adsorption, regeneration and pressure increase. Each adsorber is connected by an associated distribution conduit (6) and valved branch conduits (7) leading from one end to this distribution conduit (6), to at least three conduits (1, 2, 3, 4, 5) common to the assembly of the adsorbers (I, II; III, IV). The valved branch conduits (7) of the pair of adsorbers, adapted to ensure their connection to each common conduit (1, 2, 3, 4, 5), are connected to each other at their opposite ends to the distribution conduits (6), by a T connection (20) and are connected by this T connection (20) and a common straight tube, to the common conduit (1, 2, 3, 4, 5).