Polyurethane /Ionic Silica Xerogel Composites for CO2 Capture

Abstract

Capturing carbon dioxide (CO2) from exhaust gases is an important strategy to prevent climate change. There is a great interest in developing novel CO2 sorbents. Thus, a series of polyurethane (PU) / silica xerogels functionalized with RTILs (bmim Cl and bmim TF2N) composites were prepared and characterized. PU matrix was reinforced with functionalized silica xerogels in the range of 0.5-20 wt%. PU / functionalized silica xerogels were characterized by NMR, FTIR, DSC, TGA, DMTA and FESEM. CO2 sorption capacity and reusability were assessed by the pressure-decay technique at 298.15 K and 1 bar. Results showed that the filler aggregation in PU matrix promoted the reduction of mechanical properties. However, addition of silica xerogels functionalized with RTILs in PU matrix led to increased CO2 uptake. CO2 sorption capacity tends to increase with the incorporation of silica xerogels functionalized with RTILs in PU matrix. The best CO2 sorption value was found for PU/SX-[Bmim]-[TF2N] 0.5 composite (48.5 mgCO2/g at 298.15 K and 1 bar). Moreover, the PU/SX-[Bmim]-[TF2N] 0.5 composite showed reuse capacity and higher CO2 sorption value as compared to other reported composites.

Keywords

• Ionic silica gel
• polyurethane composites
• CO2 capture