A New CO2 Absorbent Developed from Addressing Benzylamine Vapour Pressure Using Co-solvents

Abstract

Benzylamine (BZA) has been identified as an attractive aromatic amine for CO2 capture applications. During lab and pilot scale testing it was found to have excellent mass transfer and reboiler energy performance as well as low viscosity, high thermal stability, low ecotoxicity, low corrosion potential and low cost. However its vapour pressure in aqueous solution was unexpectedly high resulting in excessive evaporative loss and process disruption. To address this a study was undertaken to find additives to use with BZA that would reduce its vapour pressure in aqueous solution. Using Hansen Solubility Parameters candidate compounds were identified and tested. This resulted in a new formulation that reduced the BZA vapour pressure and eliminated the evaporative loss issues while maintaining its otherwise good performance.