Applications: Ứng dụng của ethanolamineMonoethanolamine, MEA is used in aqueous solutions for scrubbing certain acidic gases. It is used as feedstock in the production of detergents, emulsifiers, polishes, pharmaceuticals, corrosion inhibitors, chemical intermediates. For example, reacting ethanolamine with ammonia gives the commonly used chelating agent, ethylenediamine:
Gas stream scrubbingAqueous solutions of Monoethanolamine, MEA (solutions of Monoethanolamine, MEA in water) are used as a gas stream scrubbing liquid in amine treaters. For example, aqueous Monoethanolamine, MEA is used to remove carbon dioxide (CO2) from flue gas. Aqueous solutions can weakly dissolve certain kinds of gases from a mixed gas stream. The Monoethanolamine, MEA in such solutions, acting as a weak base, then neutralizes acidic compounds dissolved in the solution to turn the molecules into an ionic form, making them polar and considerably more soluble in a cold Monoethanolamine, MEA solution, and thus keeping such acidic gases dissolved in this gas-scrubbing solution. Therefore, large surface area contact with such a cold scrubbing solution in a scrubber unit can selectively remove such acidic components as hydrogen sulfide (H2S) and CO2 from some mixed gas streams. For example, basic solutions such as aqueous MEA or aqueous potassium carbonate can neutralize H2S into hydrosulfide ion (HS-) or CO2 into bicarbonate ion (HCO3-).
H2S and CO2 are only weakly acidic gases. An aqueous solution of a strong base such as sodium hydroxide (NaOH) will not readily release these gases once they have dissolved. However, Monoethanolamine, MEA is rather weak base and will re-release H2S or CO2 when the scrubbing solution is heated. Therefore, the MEA scrubbing solution is recycled through a regeneration unit, which heats the Monoethanolamine, MEA solution from the scrubber unit to release these only slightly acidic gases into a purer form and returns the regenerated Monoethanolamine, MEA solution to the scrubber unit again for reuse.