Direct CO2-to-dimethyl Ether Hydrogenation over CuZnZr/zeolite Hybrid Catalyst: New Evidences on the Interaction Between Acid and Metal Sites

Abstract

The production of DME via one-pot CO2 hydrogenation is a strategic way of recycling CO2 with the production of a high-value added product. This work aims to investigate the effect of the main zeolite features, e.g. structure or acidity, on the activity, selectivity and stability of the catalyst for DME production via both methanol dehydration and one-pot CO2 hydrogenation. Several zeolites (i.e. FER and MFI) were synthesized and deeply characterized with XRD, B.E.T, NH3-TPD and FTIR. Obtained crystals were used as catalysts for methanol dehydration as well as for one-pot CO2-to-DME process. Obtained results allow giving new insights about the role of the interaction between metals and acid sites for an efficient DME production via one-pot CO2 hydrogenation. In particular, zeolite acidity plays a crucial role in methanol dehydration step and Lewis acid sites seems to be more active than Brønsted sites. Furthermore, metal/acid proximity plays are a key factor in one-pot CO2 hydrogenation; in fact, the catalytic performances of multifunctional catalytic bed improve by increasing the metal/acid sites proximity. The findings of this research allow to highlight the main factors to be taken into account in terms of design and optimization of new catalytic systems for DME synthesis.

Process Simulation and Environmental Aspects of Dimethyl Ether Production from Digestate-Derived Syngas

“…The adoption of lower reaction temperatures requires innovative catalytic systems with a higher activity than the conventional one. In this regard, the development of new catalysts for the production of DME from CO 2 -rich syngas or by hydrogenation of CO 2 is receiving growing attention [ 47 , 48 , 49 , 50 , 51 , 52 ]. The research is mainly focused on the improvement of catalytic activity at low temperature and stability.…”

Direct Synthesis of Dimethyl Ether from CO2: Recent Advances in Bifunctional/Hybrid Catalytic Systems

“…The dehydration of methanol was also studied over other zeolite types as the H-form of FER-type and MFI-type zeolites [113]. To obtain evidence of the influence of acidity, both zeolites were prepared with different Si/Al ratios.…”

Modelling and Environmental Aspects of Direct or Indirect Dimethyl Ether Synthesis Using Digestate as Feedstock

“…In indirect synthesis, DME is produced via methanol dehydration over an acid catalyst. More details about methanol production and methanol dehydration to DME are reported elsewhere [25][26][27][28][29][30][31][32][33].…”

“…The research is currently focused on the direct hydrogenation of carbon dioxide to dimethyl ether [32][33][34][35][36]. For this process, both technical and catalytic aspects are still open challenges.…”