NOVELTY - Production of hydrogen comprises: (i) catalytically reforming first hydrocarbon portion with steam and air in an autothermal reactor to produce a first syngas effluent; (ii) supplying the effluent to reforming exchanger; (iii) passing a second hydrocarbon portion with steam; (iv) discharging the formed second syngas effluent; (v) cooling, collecting and shift converting mixture of syngas and the first effluent; and (vi) separating the carbon dioxide-rich gas.    USE - For production of hydrogen useful for generating an electrical current and in a hydrotreating process (claimed) used to manufacturing ammonia or methanol.    ADVANTAGE - The process has very low energy consumption, is free of air separation and produces the product stream with a purity of at least 70 (preferably at least 98.5) vol.% by using the autothermal reactor having low capital cost and easy operation.    DETAILED DESCRIPTION - Production of hydrogen involves:    (a) catalytically reforming a first hydrocarbon portion with steam and air in an autothermal reactor to produce a first syngas effluent at 650 - 1050 degrees C;    (b) supplying the first syngas effluent to a reforming exchanger;    (c) passing a second hydrocarbon portion with steam through a catalyst zone in the reforming exchanger to form a second syngas effluent;    (d) discharging the second effluent from the catalyst zone adjacent the inlet to form a mixture of syngas and the first syngas effluent;    (e) passing the mixture across the catalyst zone in indirect heat exchange to cool the mixture and heat the catalyst zone;    (f) collecting the cooled mixture from an outlet of the reforming exchanger;    (g) shift converting the mixture to obtain a carbon dioxide-rich gas stream lean in carbon monoxide; and    (h) separating the carbon dioxide-rich gas stream to form a hydrogen-lean, mixed gas stream of nitrogen and carbon dioxide, and a hydrogen-rich product stream.    An INDEPENDENT CLAIM is included for apparatus for preparing syngas, comprising:    (1) the autothermal reactor;    (2) system for supplying the first syngas effluent to an inlet of a reforming exchanger;    (3) system for passing a second hydrocarbon portion with steam through a catalyst zone in the exchanger;    (4) system for discharging the second syngas effluent from the zone adjacent the inlet;    (5) system for passing the mixture across the zone in indirect heat exchange;    (6) system for collecting the cooled mixture from an outlet from the reforming exchanger;    (7) system for shift converting the mixture; and    (8) a membrane separator or a pressure swing adsorption unit for separating the carbon-dioxide-rich gas stream.