MEA - Monoethanolamine — Frequently Asked Questions

Because it reacts chemically with carbon dioxide rather than merely dissolving it, which lets it strip the gas down to very low concentrations even at the low partial pressure of atmospheric flue gas. A physical solvent would absorb almost nothing under those conditions. MEA has been used and studied for decades, so its performance and costs are well characterised, which is why it remains the reference case.

Regeneration energy. Releasing the captured carbon dioxide means breaking the chemical bond, which requires substantial heat in the stripper, and that duty dominates the operating cost and the energy penalty of the whole process. Reducing it is the central objective of most alternative solvent development.

Yes, both oxidatively, from oxygen in the flue gas, and thermally in the reboiler, producing degradation products that reduce capacity, increase corrosivity and foul the system. Operating plants therefore include reclaiming to remove those products, along with corrosion inhibitors, since MEA is corrosive to carbon steel particularly when degraded.

Detergent and surfactant manufacture, where it is the amine used to make ethanolamides and amine soaps, metalworking fluids, corrosion inhibitors and as a chemical intermediate for ethyleneamines and other derivatives. Those non-gas-treating applications account for a large share of total consumption.