Process for the production of hydrogen and the co-production of carbon
dioxide in separate streams comprising the following operations: feeding
of a solid to a first reaction zone (R1) in which a liquid or gaseous
hydrocarbon, preferably natural gas or methane, is also fed, which reacts
with the solid fed at its maximum oxidation degree (over-oxidized form),
leading to the formation of the combustion products carbon dioxide and
water and the solid at its minimum oxidation degree (reduced form);
feeding of the solid in reduced form to a second reaction zone (R2) into
which water is also fed, which reacts with the reduced form of the solid,
producing hydrogen, steam and the solid at an intermediate oxidation
degree (oxidized form); feeding of the solid in oxidized form to a third
reaction zone (R3) into which air is also fed, obtaining, from the
further oxidation of the solid, heat and the solid in over-oxidized form
to be recycled to the first reaction zone (R1), wherein the solid
contains at least one element selected from elements which, in addition
to the metallic state, have at least three different oxidation states and
are therefore capable of producing two redox pairs, in order of the
oxidation state, characterized in that in the first reaction zone (R1)
the solid in over-oxidized form and the liquid or gaseous hydrocarbon are
fed in countercurrent.