PNNL

Abstract

Global carbon dioxide (CO2) emission is expected to increase tremendously with the shift to coal-powered plants for energy generation. Capture and sequestration of CO2 are needed to mitigate environmental effects. Solvents currently used for this application are the energy-intensive aqueous amines. Here we present 10 new advanced solvents called alkanolguanidines and alkanolamidines that are potentially energy-efficient CO2-capture solvents. These solvents were synthesized in 1–3 steps from commercially available materials. One alkanolamidine derived from a 1,8-Diazabicycloundec-7-ene (DBU) base core has low vapor pressure and high viscosity, resulting in low CO2 uptake capacity at standard temperature and pressure (STP). Three imidazoline base derived alkanolamidines were non viscous but do not bind CO2 at STP, but under mild pressure effectively capture 7–10 wt%, making them suitable for high-pressure CO2 capture. All six novel alkanolguanidine molecules have low vapor pressure and low viscosity (