Moderators solid rare gases

Khatri, R. Charlton, M., Sferlazzo, P., Lynn, K.G., Mills Jr., A.P. and Roellig, L.O. (1990). Improvement of rare-gas solid moderators by using conical... 

Merrison, J.P., Charlton, M., Deutch, B.I. and Jorgensen, L.V. (1992). Field assisted moderation by surface charging of rare gas solids. J. Phys. 

The amount of hydrogen sulphide produced per day is relatively very low and a moderately sized vessel contains sufficient zinc oxide to adsorb all of the sulphurous gas that will be generated in one year. The spent adsorbent is simply removed and the vessel filled with fresh zinc oxide. This is rare. Normally a solid adsorbent (or liquid absorbent) is regenerated and re-used. This is certainly necessary in the absorption process that is used to remove the carbon dioxide over 1 tonne of carbon dioxide is produced for every tonne of ammonia. 

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