Assessment of the sustainability of intensified CO2 capture schemes

Abstract

The SDGs do address climate-related goals that are interconnected with the need to reduce greenhouse gas emissions. CO₂ capture involves the use of solvents such as Monoethanolamine (MEA), whose use, advantages, and disadvantages are well reported. Currently, there are alternative solvents that are theoretically more sustainable such as deep eutectic solvents (DES), however, a direct comparative with sustainable indicators is not always available. In this work, two schemes for the CO₂ capture process are evaluated and compared in a sustainable framework. Both schemes capture CO₂ from a combustion process to generate electricity. The first scheme considers Monoethanolamine (MEA) and the second scheme considers a DES (ChCl/ urea (1:2), considering in both schemes the use of natural gas, biogas, and coal as fuels that originate the CO₂ flux. The evaluation of both alternatives must be approached in a weighted manner and within a framework of sustainability. The results indicate that there is no single solution as the optimal solvent for CO₂ capture. It was observed that the choice of solvent is predominantly influenced by the type of fuel used in the combustion zone for electricity generation.