Method of and installation for fractionation by adsorption

A method of fractionation of a gaseous mixture by adsorption is more particularly concerned with the purification of a gaseous mixture from at least one impurity especially dehydration and decarbonation by adsorption of a gaseous mixture, the method comprising an adsorption phase during which the gaseous mixture is forced to circulate from the inlet to the outlet of an adsorption zone comprising an adsorbent mass which preferentially adsorbs at least one constituent of said gaseous mixture so as to obtain a gaseous fraction impoverished in at least said constituent; a desorption phase during which at least one regeneration fraction is heated, said heated fraction being circulated in said adsorption zone, thereby obtaining at least one fraction enriched in at least said constituent, said regeneration fraction being re-cycled in said adsorption zone; a cooling phase during which at least one cooling fraction is cooled and said cooled fraction is caused to circulate in said adsorption zone, said cooling fraction being re-cycled in said adsorption zone; and in which the said regenration fraction is exclusively obtained from the residual gaseous fraction present in said adsorption zone at the end of the adsorption phase.