Formulation and processing of dual functional Adsorbent/Catalyst structured monoliths using an additively manufactured contactor for direct Capture/Conversion of CO2 with cogeneration of ethylene

Adsorption-Enhanced Bifunctional Catalysts for In Situ CO2 Capture and Utilization in Propylene Production: A Proof-Of-Concept Study

“…The combined adsorption/catalysis performances of the samples were assessed using our in-house setup which has been reported previously. , A sample weight of 0.2 g was packed into the reactor bed with quartz wool. The monolith dimensions are shown in Figure .…”

“…The monoliths were 3D-printed using our established direct printing technique with the ink ratios outlined in Table . ,,, It should be noted here that the CaCO 3 concentration before printing was greater than 50 wt %; however, after calcining the printed structures and removing CO 2 from CaO, the ratio of the adsorbent to the catalyst was 1:1. Before printing, the powder components were placed in a PTFE bottle and mixed with ∼10 mL of DI water, after which they were rolled at 60 rpm for 2 day at 25 °C.…”

“…Having said this, another area which is currently underdeveloped in the area of BFM materials for CO 2 capture and utilization processes is the extent to which such composites have been employed for different reactions, as there have only been a handful of applications in this area. We anticipated that the printed BFM monoliths could be reasonably applied to singular-bed CO 2 capture and ODHP utilization, as our previous studies indicated that directly 3D-printed heterogeneous catalyst monoliths without the adsorbent phase have exceptional performance in this reaction. , Nevertheless, because combined CO 2 capture and ODHP reaction would likely require higher temperature compared to ODHP, alone, we concluded that a metal screening would be needed to identify which BFM composites would be best suited for this process, as the best material for ODHP at 550 °Cwhich was reported previouslyis unlikely to display the best performance at 600–700 °C.…”

“…One approach is to utilize CO 2 as a feedstock in dehydrogenation reactions; however, adsorption/catalysis processes are typically performed in separate beds, which necessitates large thermal gradients and generates high-energy-costs. For examples, researchers have reported the use of CO 2 as a light oxidant feedstock in dehydrogenation reactionssuch as oxidative dehydrogenation of ethane (ODHE) or oxidative dehydrogenation of propane (ODHP)where the gas both (i) reoxidizes spent active sites and (ii) is converted into CO, which is a precursor for synthetic fuels. − Granted, using CO 2 as a synthetic fuel would still end with it being emitted into the atmosphere, but recent advancements in direct air capture (DAC) technology could eventually allow for atmospheric capture followed by subsequent CO 2 utilization as a feedstock. By powering this process with renewable or nuclear energy, a circular carbon economy can then be achieved with this approach.…”

Shaping techniques of adsorbents and their applications in gas separation: a review

“…In, Ce, Cr, and Mo metal dopants were compared and Cr–CaO/ZSM-5 was found to have the best performance with 56% CO 2 conversion, 91.2% C 2 H 4 selectivity, and 33.8% C 2 H 4 yield due to the high acidity and numerous oxidation states of Cr 2 O 3 . The subsequent study 238 compared another four metal dopants V, Ga, Ni, and Ti, and V–CaO/ZSM-5 exhibited an improved adsorption/catalysis effect. Later, the metal-doped CaO/ZSM-5 materials were used to perform integrated direct air capture and oxidative dehydrogenation of propane.…”