Insights in the development of a new method to treat H2S and CO2 from sour gas by alkali

In this work we have studied the absorption of H2S and CO2 in NaOH solutions (0.01, 0.1, 0.5, 1 and 2 M), in order to treat these acid gases coming from sour gas sweetening process. Our results show that gas dissolution/neutralization is faster at the lowest NaOH concentrations tested in consequence a compromise must be reached between bisulfide–sulfide yield and reaction fastness.

► Dissolution is the lowest step in the H2S neutralization bye NaOH solutions. ► H2S dissolution is faster in less concentrated NaOH solutions. ► CO2 dissolution and neutralization is faster than H2S even though they are of same magnitude order.