Liquid desulfurizer

Due to proton transfer, the reaction between H2S and MDEA(N- methyldiethanolamine) is a transient chemical reaction controlled by gas membrane: H2S+R2NCH3=[R2NHCH3]+[HS]- As MDEA is a tertiary amine, CO2 reacts with amine only after it forms bicarbonate with water: CO2+H2O+R2NCH3 R2NHCH3+HCO3(2) Because CO2 and water need a slow intermediate process, this huge difference in reaction rate constitutes the basis of selective absorption, that is, MDEA has higher selectivity for H2S absorption in the presence of CO2. The acidic tail gas is washed with water to remove CH3OH and HCN, and then enters the bottom of the absorption tower to make countercurrent contact with the lean amine liquid added from the top, and the purified gas after desulfurization escapes from the top of the absorption tower. The rich amine solution leaving the absorption tower is heated by exchanging heat with poor amine through the heat exchanger, and then regenerated in the regeneration tower. The regenerated acid gas containing H2S and CO2 is taken as the feed of Claus plant, and the poor amine is pumped to the absorption tower by cooling, which is named as N- methyldiethanolamine focus product/methyl alcohol amine series, or MDEA external view (25℃), and is colorless to yellowish transparent liquid at normal temperature. Content (%) (GC)≥98.0% Total amine value 450-480mgKOH/g Color Ze (G) (Hazen)≤120 water content (%) ≤1.0% Soluble range can be miscible with water and alcohol, but slightly soluble in ether. The application fields are widely used in oil field gas and coal gas desulfurization and purification emulsifier, acid gas absorbent, acid-base control agent and polyurethane foam catalyst. Carbon dioxide in synthetic ammonia can be removed with the participation of activator. In addition, MDEA can also be used as insecticide, emulsifier, semi-finished product of fabric auxiliary agent, intermediate of anti-tumor drug nitrogen mustard hydrochloride, catalyst of urethane coating, fiber auxiliary agent, etc. At the same time, MDEA is also a drying accelerator of paint.