Overcoming Storage Limitations in SiO2—Supported Dual Function Materials for CO2 Capture and Methanation

The role of the support for Dual Function Materials (DFMs) is critical in the overall activity of the materials, affecting both storage and conversion functions. Through microreactor and FT-IR investigation, the utilization of SiO2 as support for the integrated CO2 capture resulted in low CO2 uptakes when using Ru- and Na- based DFMs, due to the weak protonic acidic nature of the support as well as its non-interacting nature. These properties cause the agglomeration of the Na-based sorbent, increasing its bulk basicity and lowering its effectively available amounts when higher Na loadings materials are prepared. On the other hand, higher efficiency of integrated CO2 capture and conversion has been obtained by using segregated configurations, that is, physical mixtures of reducing/storage formulations, that in our conditions can overcome detrimental storage material-support interactions.