Life Support Systems
Section 4.3.5.
Home Tour Join! Contents Team News Catalog Search Comm

Monoethanolamine as a CO2 Scrubber

On submarines, CO2 is removed with a chemical scrubber, called monoethanolamine. MEA is supplied in liquid form, although it may be a solid dissolved in water. When cold, MEA takes in CO2, when heated, MEA gives up the CO2. On submarines, the CO2 is pumped overboard. On a lunar base, the CO2 would be stored under pressure or liquified until either there was enough plant life to recycle it naturally, or enough spare energy available to dissociate the CO2 into carbon and O2.

LiOH is suitable for short duration missions, but is a one-time-use item. It turns into lithium carbonate, after which it absorbs no more CO2, while MEA absorbs and gives up CO2 in a continuous heating/cooling cycle.

LiOH is currently used on spacecraft because of weight considerations--the weight of the needed LiOH is less than the weight of a regenerative CO2 scrubber. Also, current MEA-type scrubber designs require gravity to work.

For a short duration confinement with a limited number of people, LiOH is the better solution regarding CO2. For longer missions, MEA becomes more economical, but after that, immediate chemical processing would be more effective once the necessary equipment is in place in the habitat.

Life Support Systems

Home Tour Join! Contents Team News Catalog Search Comm
ASI W9601195r1.1. Copyright © 2004 Artemis Society International, for the contributors. All rights reserved.
This web site contains many trade names and copyrighted articles and images. Refer to the copyright page for terms of use.
Maintained by ASI Web Team <>.
Submit update to this page. Maintained with WebSite Director. Updated Sun, Aug 15, 1999.