Abstract: A process for the fractionation of a gaseous mixture containing hydrogen, light aliphatic hydrocarbons and light aromatic hydrocarbons wherein following compression of the mixture and separation of one or more light fractions, a gas is contacted with light aliphatic hydrocarbons and then hydrogen is separated by permeation. A series of distillation steps makes it possible to isolate the aliphatic hydrocarbons and the aromatic hydrocarbons subsequent to the separations.

Abstract: The invention relates to a process for the production of hydrogen by steam reforming of methanol, in which water and methanol are reacted (4), under relatively high pressure, over a suitable catalyst. The gases emitted from the reaction are contacted (10), after condensation (7) under relatively high pressure, with an adsorption agent, such that the byproducts of the reaction are adsorbed and a hydrogen-rich gas is liberated (11). Also, byproducts which are recycled to the steam reforming reactor (4), are periodically desorbed under relatively low pressure at along with a fraction of the hydrogen present in the adsorption zone (10), after being submitted to recompression (13) and removal (14), under relatively high pressure, of at least a portion of carbon the dioxide, the desorbed gas fraction is recycled to the steam reforming reactor.