Why is it said that the heat of dissolution released upon absorption of H2S and COS is compensated by the desorption heat of CO2 in methanol?
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Dear experts, I’m a newcomer to the field of chemistry. Why is it said that the heat of absorption of hydrogen sulfide and carbonyl sulfide by methanol enriched in carbon dioxide is offset by the heat of desorption of carbon dioxide from methanol? Where does this heat of desorption originate from? And why does the absorption tower have carbon dioxide being desorbed there? Thank you
Methanol-rich fluid containing CO2 enters the lower column; when absorbing H2S, H2S has a higher solubility than CO2, and the absorption of H2S leads to the release of some CO2. The dissolution of CO2 releases heat, while the release of CO2 absorbs heat, thereby generating cooling effect. Therefore, no intermediate cooler is installed for H2S absorption in the lower tower.