Influence of divalent metal ions on CO2 valorization at room temperature by isostructural MOF-74 materials. Issue 2 (April 2023)

• Record Type: Journal Article
• Authors: Tapiador, J.; García-Rojas, E.; López-Patón, P.; Calleja, Guillermo; Orcajo, Gisela; Martos, Carmen; Leo, Pedro
• Is Part Of: Journal of environmental chemical engineering. Volume 11:Issue 2(2023)
• Publication Date: 2023-04
• Subjects: Metal organic framework -- MOF-74 -- Heterogeneous catalyst -- CO2 conversion -- Epoxides; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2023.109497
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: At present, the concentration of carbon dioxide (CO2 ) has increased to unprecedented levels. The valorization of CO2 into high value-added chemicals can be a very interesting alternative to stabilize the concentration of this atmospheric pollutant while the current energy transition takes place. The well-known M-MOF-74 family (M= Mg, Co, Ni, Cu and Zn) have been evaluated as heterogeneous catalysts to carry out several cycloaddition reactions at room temperature with several epoxides (epichlorohydrin; 1, 2-epoxyhexane and styrene oxide) as substrate, to evaluate the influence of the metal in this reaction. Zn-MOF-74 showed the highest catalytic activity, always with conversion and selectivity values above 93% regardless of the epoxides studied and the carbonates obtained, due to the higher acid character of the Zn 2+ ion. Therefore, it is confirmed that the influence of the metal is key in this reaction, despite the fact that Cu-MOF-74 with an adsorption capacity of 5 mmol/g of CO2 (45 °C, 5 bar) converts 26% of styrene oxide under the conditions evaluated compared to Zn-MOF-74, which is the material with the lowest adsorption capacity (3 mmol/g of CO2 ) and shows a conversion of 93%. Highlights: Room temperature CO2 -epoxide cycloaddition reaction under solvent free conditions. The catalytic behaviour of MOF-74 materials in CO2 valorization differs from their adsorption capacity. Zn-MOF-74 boosts high epoxide conversion and high selectivity to cyclic carbonates. MOF-74 materials showed high stability and catalytic activity with linear epoxides.