Abstract: A system for separating CO2 from combustion exhaust gas by means of MCFC multistacks comprises: a first MCFC unit (10) and a second MCFC unit (20), having respective cells (11, 21) with respective cathodic compartments (12, 22) and respective anodic compartments (13, 23); at least one CO2-capture unit (31, 32); and a connection network (30) that connects the units (10, 20) to one another and to the CO2-capture unit (31, 32); the first unit (10) is formed by one or more MCFC cells (11) without active direct internal reformer; and the second unit (20) is formed by one or more MCFC cells (21) with active direct internal reformer; the units (10, 20) are connected in such a way that the exhaust gas to be treated are supplied to the cathodic compartments (12) of the cells (11) of the first unit (10), and the cathodic compartments (22) of the cells (21) of the second unit (20) are supplied with cathodic exhaust of the first unit (10), either alone or with additions that do not include portions of exhaust gas that ha