The incorporation of CO₂ as reactant co-fed with syngas for the direct synthesis of dimethyl ether (DME) using a bifunctional (CuO–ZnO–Al₂O₃/γ–Al₂O₃) catalyst in a packed-bed reactor has been proposed. The presence of CO₂ in this system favors H₂O formation that hampers the reaction of methanol dehydration towards DME. Therefore, the employment of a zeolite membrane for the in situ H₂O removal in a packed-bed membrane reactor (PBMR) has been theoretically evaluated. A mathematical model describing mass transport through the membrane of all the components involved in the DME synthesis has been developed. The model has been used to predict the process performance and to define the most favorable membrane characteristics, with feed and sweep streams flowing countercurrently in single-pass mode. The mass transport characteristics of the zeolite membranes proposed in the present study ranged from those permeable to all the components present in the DME reaction site, i.e. ZSM5, mordenite and silicalite, to those ideally permselective to water. Simulation runs predicted that the application of any zeolite membrane always promoted the transformation of CO₂ into DME, although yields and conversions were highly dependent on membrane transport characteristics. Hence, membranes highly selective to H₂O were required to reach sufficient conversions of CO₂ into DME while, low H₂O permeances (0.5–1.2 × 10⁻⁷ mol Pa⁻¹ m⁻² s⁻¹) procured an enhancement on DME yield. Our results highlight the relevance of further research and development of zeolite membranes with improved H₂O permselectivity as one of the major challenges in processes for CO₂ capture and transformation into DME.