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This work involves the production of magnesium in the form of Mg(OH) 2 from serpentinite rock (nickel mine tailing) material followed by conversion into MgCO 3 using a pressurised fluidised bed (PFB) reactor operating at 400°C-600°C and pressures up to 2.85 MPa. Our approach is rooted in the thermodynamic fact that the reaction between Mg(OH) 2 and gaseous CO 2 forming MgCO 3 and water releases significant amounts of heat. The main problem is, however, the chemical kinetics; the reaction is slow and has to be accelerated in order to be used in an economically viable process for large-scale (~1 Mt/a) CO 2 sequestration. We have constructed a labscale PFB reactor test-setup for optimising the carbonation reaction. At high enough temperatures and conversion levels the reaction should provide the heat for the proceeding Mg(OH) 2 production step, making the overall process energy neutral. So far we have been able to achieve a conversion degree of 26% at 500°C and 2.85 MPa after 30 min (particle size 125-212 μm). In this paper the test facility and our latest results and progress on CO 2 mineral carbonation are summarised. Also, the possible integration of the iron as a feedstock for iron and steel production will be briefly addressed. An interesting side-effect of this carbon dioxide capture and storage (CCS) route is that significant amounts of iron are obtained from the serpentinite rock material. This is released during the Mg(OH) 2 production and can be of great interest to the iron-and steel producing sector, which at the same time is Finland's largest CO 2 producer.