Quaternary Ammonium Featuring Nano-porous Polymer for CO2 Capture and Conversion

Abstract

The climate change has been believed that the increase in atmospheric CO2 level affects global warming and change to world climate as a result of using fossil fuels. Among the various attempts to solve this problem, carbon capture utilization (CCU), an attractive alternative to CCS, has been highlighted in view of the fact that CCU has the capability to provide not only reduction in carbon emissions, also economical product by capturing CO2 and utilizing CO2 subsequently. In the CCU process, CO2 is difficult to be utilized as feedstock due to thermodynamic stability of CO2. Such issue can be resolved by designing an appropriate catalyst to be used in conversion application.The formation of cyclic carbonates has attracted attention based on the fact that it does not require redox reagent to change states in suitable catalytic system. However, from a sustainable perspective, the challenge associated with a majority of the reported systems are the need for high pressures and use of co-catalysts to enhance the reactivity. We hypothesized that porous materials having inherent feature like high surface area, pore size, and tunability of chemical functionalities furnish availability of active sites per amount of substrate and thereby acceleration of the rate of the reaction. Hereby, we report comprehensive syntheses of nano-porous covalent organic polymers (COPs) with featuring quaternary ammonium salts and their application for carbon dioxide utilization in ambient condition and without co-catalyst. We observed that this catalyst showed excellent conversion and selectivity for substrates like epichlorohydrin under ambient pressure and co-catalyst/additive free conditions. Also, the catalyst shows high conversion (>99%), high selectivity (>99%).