Catalytic Tandem CO₂–Ethane Reactions and Hydroformylation for C3 Oxygenate Production

Abstract

The strategy of the tandem hydroformylation reaction for C3 oxygenate production from CO2 and ethane represents an opportunity to simultaneously upgrade greenhouse gas CO2 and the large-reserved shale gas into value-added liquid products. One of the challenges is how to tune and achieve the appropriate ethylene/CO/H2 ratios for the downstream hydroformylation. Herein, we analyze and identify the desired ethylene/CO/H2 ratios by considering different combinations of main and side reactions of CO2 and ethane, based on which the PtSn3/γ-Al2O3 catalyst was identified as promising to enable the catalytic tandem hydroformylation reaction. The combined studies of reactor evaluation, in situ and ex situ characterizations, and theoretical calculations revealed that the Pt cluster/SnO x interfacial structures dominated the simultaneous dehydrogenation and dry reforming of ethane, thereby allowing the coformation of ethylene, CO, and H2 that were subsequently converted into C3 oxygenates in the tandem hydroformylation reactor. The current work not only demonstrates the design principles of suitable catalysts for the tandem-reactor strategy but also highlights the utilization of CO2 and shale gas to produce value-added oxygenate products.

Descriptor-based identification of bimetallic-derived catalysts for selective activation of ethane with CO2

“…4), one can roughly estimate the corresponding C 2 H 4 selectivity from CO 2 -activation of C 2 H 6 over a bimetallic system, simply using the DFT-calculated values for the two descriptors, reactive oxygen binding energy and alloy surface formation energy. Accordingly, the C 2 H 4 selectivity measured previously for bimetallic-derived systems, such as NiFe 3 (experiment: 78% 16 vs. descriptor-based estimation: ∼75%), PdFe 3 (86% 23 vs. ∼85%), PtCo 3 (1% 13 vs. ∼0%), PtNi 3 (1% 18,19 vs. ∼0%), and PtSn 3 (83% 36 vs. ∼75%) can be estimated, which reproduced the experimental values reasonably well. Therefore, the DFT-calculated formation energies of alloy surfaces and the reactive oxygen binding energies can be used as universal descriptors to screen the bimetallic-derived catalysts for the selective activation of C 2 H 6 with CO 2 .…”

“…We note here that only the reaction energies for the elementary steps involved were calculated, by assuming a BEPlike correlation between the reaction energy and the corresponding activation barrier according to our previous DFT studies on the activation of light alkanes with CO 2 . 24,36 On…”

Utilizing CO2 as a Reactant for C3 Oxygenate Production via Tandem Reactions

“…Thus, it is critical to reduce the temperature in the first reactor to enable a completely catalytic tandem process, in which the C 2 H 4 /CO/H 2 ratios can be better tuned via the selection of appropriate catalysts. Xie et al recently analyzed and identified the desired C 2 H 4 /CO/H 2 ratios by considering different combinations of main and side reactions of CO 2 and ethane . To obtain a C 2 H 4 /CO/H 2 ratio that is close to the typical feed ratio (1/1/1) for the subsequent hydroformylation, the analysis showed that the desired catalysts for the first reactor should enable multiple simultaneous reactions of direct dehydrogenation of ethane (DDHE), ODHE, DRE, and RWGS: i.e., either ODHE + DDHE + DRE (theoretical product ratio of 1/1/0.88) or DDHE + RWGS + DRE (theoretical product ratio of 1/1.15/1).…”

“…24 In the tandem configuration with PtSn 3 /γ-Al 2 O 3 catalyst at 600 °C in the first reactor, the obtained C 3 Oxy productivity was comparable to that of the aforementioned Fe 3 Ni 1 /CeO 2 catalyst at 750 °C (Figure 3g). 10 2.1.2. Plasma−Thermocatalytic Scheme (P-TC).…”

“…In this Perspective, we consider four ambient-pressure tandem reaction pathways (Figure ) for producing C 3 Oxys from CO 2 , using either ethane or water as the hydrogen source: (1) thermocatalytic CO 2 -assisted dehydrogenation and reforming of ethane to ethylene, CO, and H 2 , followed by thermocatalytic heterogeneous hydroformylation (TC-TC), , (2) one-pot conversion of CO 2 and ethane using plasma-activated reactions in combination with thermocatalysis (P-TC), (3) electrocatalytic CO 2 reduction to ethylene, CO, and H 2 , followed by thermocatalytic hydroformylation (EC-TC), and (4) electrocatalytic CO 2 reduction to CO, followed by electrocatalytic CO reduction (EC-EC) . We first introduce the relevant reactions and proof-of-concept results for the four different tandem schemes.…”