An equilibrium analysis of the reaction system for the synthesis of methanol based on CO2 & CO hydrogenation and Water-Gas Shift reaction was performed to define the conditions under which the reaction system favours methanol production. The results were compared with a sensitivity analysis in a simplified Tubular Packed Bed Reactor (TPBR) with commercial Cu/Zn/Al2O3 catalytic bed. As a result, the highest feedstock conversion to methanol at equilibrium was found with increasing pressure, decreasing temperature, and setting the initial H2/CO2 ratio to 2.55. The reactor model showed similar behaviour in pressure and H2/CO2 inlet ratio but differed in the temperature effect on feedstock conversion to methanol. Differences between equilibrium analysis and final reactor conversions are briefly discussed. © 2023 Elsevier B.V.