Methyldiethanolamine solutions

Kierzkowska-Pawlak H, Zarzycki R (2002) Solubility of carbon dioxide and nitrous oxide in water + methyldiethanolamine and ethanol + methyldiethanolamine solutions. J Chem Eng Data 47 1506-1509... 

Benamor, A. and Aroua, M. K. 2007, An Experimental Investigation on the Rate of CO2 Absorption into Aqueous Methyldiethanolamine Solutions, The Korean journal of Chemical Engineering, 1-24,16-23. 

Dicko, M. CoqueleL C. fame, C. Northrop, S. Richon, D. 2010, Acid gases partial pressures above 50wt% aqueous methyldiethanolamine solution Experimental work and modeling. Fluid Phase Equilibira, 289, 99-109. 

Jou, F-Y. Mather, A. and Otto, F. 1993b, Solubility of mixtures of hydrogen sulfide and carbon dioxide in aqueous N-methyldiethanolamine solutions. Chem. Eng. Data., 38,75-77. 

Figure 10.375 Separation of short-chain fatty acids in a "semilean" A/-methyldiethanolamine solution. Separator column lonPac AS10 eluent 3.5 mmol/L Na2B407 flow rate 1 mUmin detection suppressed conductivity injection volume 25 pL peaks (a) 1.9mg/L fluoride (1),...

Figure 10.377 Separation of heat-stable salts in a "semilean" N-methyldiethanolamine solution applying a gradient elution technique. Separator column lonPac AS11 eluent NaOH gradient flow rate 2 mL/min detection suppressed conductivity injection volume 25 pL ...

Tertiary amines cannot form carbamates, but they react with CO2 in aqueous solvents to form hydrogencarbonate (3.20). Yu and Astarita [29] studied the kinetics of the absorption of carbon dioxide in MDEA (bis(2-hydroxyethyl) methylamine 77-methyldiethanolamine) solutions and... 

Rgure 2-70. Viscosity of Diglycolamlne and methyldiethanolamine solutions. MDEA data from Teng et al. (1994) DGA data trom Jefferson Chemical Co. (1969)... 

Merkley, K. E.. Christensen, J. J., and Izatt, R. M., 1986, Enthalpies of Solution of CO2 in Aqueous Methyldiethanolamine Solutions, GPA Research Report 102, Project 821, Brigham Young University, Provo, UT, September. 

H. Kierzkowska-Pawlak, R. Zarzycki, Calorimetric measurements of CO2 absorption into aqueous N -methyldiethanolamine solutions. Chem. Pap. 56, (2002)... 

K.E. Merkley, J.J. Christensen, R.M. Izatt (1986) Enthalpies of solution of CO2 in aqueous methyldiethanolamine solutions. Gas Processors Association, Research, Report, vol 102... 

S. Ma mun, R. Nilsen, H.F. Svendsen, O. Juliussen, Solubility of carbon dioxide in 30 mass % monoethanolamine and 50 mass % methyldiethanolamine solutions. J. Chem. Eng. Data 50(2),... 

B. Lemoine, Y.G. Li, R. Cadours, C. BouaUou, D. Richon, Partial vapor pressure of CO2 and H2S over aqueous methyldiethanolamine solutions. Fluid Phase Equihb. 172(2), 261-277 (2000)... 

Xu, S. Qing, S. Zhen, Z. Zhang, C. Carroll, J. J. Vapor pressure measmements of aqueous N-methyldiethanolamine solutions. Fluid Phase Equilib. 1991, 67, 197-201. 

Bis(2-chloroethyl)methylamine hydrochloride. N-methyldiethanolamine (59.58 g, 0.5 mole) is dissolved in 50 mL of chloroform and added dropwise with stirring to a solution of freshly distilled thionyl chloride (158.17 g, 1.33 mole) in 70 mL of chloroform. After the addition is complete, the solution is refluxed for 3 h and then left to stir overnight at room temperature. The solvent and the excess thionyl chloride are removed by rotary evaporation to yield an off-white solid. This product is recrystallized from acetone and... 

In an exactly analogous manner Sn(OCH2CH2)2NCH3 can be obtained from the reaction of tin (II) butoxide and 7V-methyldiethanolamine in dry toluene. However, since the product is slightly soluble in hot toluene, the volume of the final reaction solution must be reduced to about 100 ml to facilitate precipitation of the product. The material is then filtered and dried in vacuo to give 13.1 g (90%) of product. 

Note It seems relevant that aqueous solutions of A-methyldiethanolamine (77), employed to remove H2S from hydrocarbon gases, gradually accumulate inter alia 1,4-dimethyl-, l-(2-hydroxyethyl)-4-methyl-, and l,4-bis(2-hydrox-yethyl)piperazine. 

Methyldiethanolamine (MDEA) and solutions of MDEA have increased in use for gas treating (150,151). Additional gas treating capacity can often be obtained with the same working equipment, because of the higher amine concentrations that can be used. 

The solvent used for the absorption/desorption experiments is a 99% methyldiethanolamine (MDEA) from Sigma-Aldrich in a 50 wt% distilled water solution. 

Chemical absorption, which involves a reversible reaction, forms weak chemical bonds between the solvent and the species to be removed. All processes using amines, such as monoethanolamine or methyldiethanolamine, and alkaline salt solutions belong to this category. 

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