Solutions in sulfur recovery
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The principle behind methyl diethanolamine solutions absorbing H2S and CO2, and how they carry out this absorption
The reaction between H2S and MDEA is an almost instantaneous chemical reaction: H2S + R2NCH3 = R2NHCH3+ + HS. Since MDEA is a tertiary amine with no hydrogen atoms attached to its nitrogen atom, it reacts with MDEA only after CO2 and H2O form bicarbonates: CO2 + H2O = HCO3- + H+. The entire reaction is as follows； CO2 + H2O + R2NCH3 = R2NHCH3 + HCO3–. The reaction that produces bicarbonate is generally considered to be a slow reaction; as a result, during the brief period of gas-liquid contact, the actual amount of CO2 absorbed is lower than the equilibrium value. The reaction between H2S and MDEA occurs instantaneously, while the reaction between CO2 and H2O involves a slow intermediate process; therefore, it is believed that the reaction between H2S and MDEA is controlled by the gas phase, whereas the reaction between CO2 and MDEA is controlled by the liquid phase.
How many steps are there in the reaction between a gas and a solution? For example, the gas phase and liquid phase control mentioned above