Methyl Diethanol Amine
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Transcript of Methyl Diethanol Amine
METHYL DIETHANOL AMINE
R.SRIKANTHK.YESWANTH
N-METHYL DIETHANOLAMINE – MDEA
• It is a clear, Colorless or Pale Yellow liquid with Ammonical Odor.
• It is miscible with water, alcohol and benzene.
• Methyl Diethanolamine is also known as an MDEA or N-Methyl Diethanolamine.
• MDEA is more efficient absorber then MEA & DEA for sulphur contains impurity and acid gases found in natural gas processing
• Methyl Diethanolamine is widely used as a decarbonized and Sweating agent in chemical, oil refinery, Gas synthesis, Natural gas & gas
Typical Physical Properties
• Boiling Range, o C 247 (477) • Flash point, PMCC, °C (°F) 116 (240) • Freezing Point, o C (o F) -21 (-5.8) • Specific gravity, 20/20o C 1.0431 • Vapor pressure, 20o C, mm Hg• Viscosity, cSt, 100o F 36.8 • Weight, lb/gal, 20o C 8.69 • Water solubility Complete
• MDEA IS USED AS ASOLVENT
Using Amine as a Solvent for Chemical Absorption
• Amines are compounds formed from ammonia (NH3) by replacing one or more of the hydrogen atoms with another hydrocarbon group. • Replacement of single hydrogen produces a primary amine, replacement of two hydrogen atoms produces a secondary amine, and replacement of all three of the hydrogen atoms produces a tertiary amine.• Primary amines are the most reactive, followed by secondary and tertiary amines
Tertiary Amines
• Methyldiethanolamine (MDEA), a tertiary amine, selectively removes H2S to pipeline specifications while “slipping” some of the CO.• As noted previously, the CO2 slippage occurs because H2S hydrolysis is much faster than for CO2, and the carbonate formation reaction does not occur with a tertiary amine.• Consequently, short contact times in the absorber are used to obtain the selectivity.• MDEA has a low vapor pressure and thus, can be used at concentrations up to 60wt% without appreciable vaporization losses. • Even with its relatively slow kinetics with CO2, MDEA is used for bulk removal of CO2 from high concentration gases because energy requirement for regeneration are lower than those for the other amines
METHYL DIETHANOLAMINES TECHNOLOGY PROCESS DESCRIPTION
• Methyl DiEthanolamines are manufactured by reacting Ethylene oxide and excess Mono Methyl Amine (MMA) in an aqueous solution, followed by separation of excess MMA, water and the mixed Methyl Ethanolamine fractions.
• METHYL DIETHANOLAMINES • C2H4O + CH3NH2 H3CNH-CH2-CH2OH • Ethylene Oxide Mono Methyl Amine Mono Methyl Ethanolamine • C2H4O + CH3CNH-CH2-CH2-OH H3CN(CH2-CH2-OH)2 Ethylene Oxide Mono Methyl Ethanolamine Methyl Diethanolamine
• The reaction is simultaneous and the product mix is dependent on the molar ratios in which the two reactants are charged and other operational parameters.• The two raw materials - Ethylene Oxide and MMA are continuously charged into the reactor under carefully controlled conditions of temperature, pressure and composition.• The ensuing product after reaction contains a mixture of the Methyl DIEthanolamines, water and excess MMA. This is processed through a series of towers where the excess MMA and water are removed progressively and finally a dehydrated mixture of the Methyl DiEthanolamines is obtained.
• This dehydrated mixture of Methyl Ethanolamines is then purified into distillation columns where each of the amines, namely Methyl Monoethanolamine, Methyl Diethanolamine and Poly Methyl Ethanolamine (Heavies) are obtained after controlled fractional distillation. • The products are collected in intermediate tanks, checked for quality and then are stored in the respective product storage tanks. • Provision has been made to recycle the product back in case non-standard product is obtained.
PROCESS ADVANTAGES
• Non-Catalytic Low Pressure Reaction.
• High selectivity and yield to valuable MDEA product.
• Product conforming to International Standards