Carbon Dioxide Utilisation in the Production of Chemicals, Fuels and Materials

Abstract

Carbon dioxide is accumulating in the atmosphere as the natural carbon cycle is not able to absorb the anthropogenic CO2, despite the latter representing roughly 3% of the natural cycled amount. The influence of its growing concentration on possible climate change is of grave concern. Strategies for reducing its emission to the atmosphere are under urgent evaluation. The capture from point-concentrated sources is an option that can separate CO2 from flue gases; the captured CO2 can be either disposed of in natural fields (CCS) or used (CCU). CCS is site specific (existence of suited natural sites), requires large amounts of energy and comes with a high economic cost, but has the potential for disposing of large volumes of CO2. CCU can recycle carbon and contribute to avoiding fossil carbon extraction. The conversion of CO2 has different energy requirements depending on the nature of the chemicals derived from it; if the entire molecule is fixed into a compound (organic or inorganic, molecular or polymeric), the energy requirements are lower than if it is converted into energy-rich species such as fuels. This option requires that perennial primary energy sources (mainly solar and wind energy) are used for the conversion of CO2. In a changing paradigm of use of primary energy sources, the conversion of large volumes of CO2 is possible. This chapter presents the available opportunities of using CO2 as a source of carbon for making specialty and bulk molecular compounds, fuels or materials. The last use encompasses organic polymers such as polycarbonates, polyurethanes, urea-derived polymers, polyolefins and inorganic carbonates.