Ethanolamine, mono reaction

Commercial production of ethanolamines (EOA) is by reaction of ethylene oxide with aqueous ammonia. The ethylene oxide reacts exothermically with 20% to 30% aqueous ammonia at 60 to 150°C and 30 to 150 bar in a tubular reactor to form the three possible ethanolamines (mono-ethanolamine - MEA, di-ethanolamine - DEA and tri-ethanolamine - TEA) with high selectivity. The product stream is then cooled before entering the first distillation column where any excess ammonia is removed overhead and recycled. In the second column, ammonia and water are removed and the EOA s are separated in a series of vacuum distillation columns. 

Let us now consider the following reaction in which several ethanolamines (mono-, di-, and tri-)... 

Developers of the process reported that the mono-, di-, and triethanolamines are formed in approximately equal amounts with a modest dominance by the mono-ethanolamine. The reaction depends on the ratio between reactants and is adjusted intentionally. BPA personnel report that the pH drops approximately 1.5 points in the two months following the treatment. 

GirhotolAmine Process. This process developed by the Girdler Corporation is similar in operation to the alkali carbonate processes. However, it uses aqueous solutions of an ethanolamine, ie, either mono-, di-, or triethanolamine. The operation of the Girbotol process depends on the reversible nature of the reaction of CO2 with monoetbanolamine [141-43-5] to form monoethanolamine carbonate [21829-52-7]. 

Neutralization agents may be caustic soda (predominantly), ammonia, mono-ethanolamine, and triethanolamine. Examples of reaction equations are as follows ... 

Whereas silylation-amination of 2-amino-5,8-dihydroxypyrimido[4,5-d]pyridazine 269 with 3-amino-l-propanol, HMDS 2, and TsOH affords, after 24 h at 120-140 °C, the mono-8-hydroxypropylamino derivative 270 in 50% yield [79], reaction of 269 with a shght excess of ethanolamine and HMDS 2 provides, after 30 h at 120-150°C, only 20% of the bis(amino) product 271 [79]. (Scheme 4.31) A larger excess of ethanolamine and longer reaction times wiU certainly increase the yield of 271. 

The organic deliquescents tried were ethylene glycol (EG), triethylene glycol (TEG), and mono-ethanolamine (MEA) The experimental runs made adding 5 wt% of EG, TEG, or MEA are presented in Table III. At 75% relative humidity, all three additives slightly decreased the Ca(0H)2 converted after 1 hour of reaction, when compared with the conversion of pure Ca(0H)2 at the same experimental conditions. 

In sclerotherapy an irritant is introduced into varicose veins and esophageal varices, causing a local inflammatory reaction and obliteration of the veins concerned. Sclerosing agents include lauromacrogol 400, mono-ethanolamine oleate, sodium morrhuate, and sodium tetradecylsulfate. 

Diethanolamine is prepared commercially by the ammonolysis of ethylene oxide. The reaction yields a mixture of mono-ethanolamine, diethanolamine, and triethanolamine which is separated to obtain the pure products. 

Ammonia and oxirane itself give various proportions of mono-, di-, and tri-ethanolamine according to the proportions of the reactants used the products can be separated by distillation.1108 Reaction with primary or, more so, secondary amines is more clear-cut. 2-(Diethylamino)ethanol is best obtained in this way ... 

The reactions are exothermic and are usually carried out at 50-100°C. The product ratio is generally controlled by the ratio of ammonia to alkylene oxide. A high ammonia-to-alkylene oxide ratio is used when mono- and dialkanolamines are desired. A recycle technique can be used when di- and triethanolamine are desired excess monoalkanolamine is added to suppress its further formation. This product ratio flexibility is of great value when demands shift from one product to another. Some of the more commercially important substituted alkanolamines made this way are aminoethyl ethanolamine (from ethylenediamine and EO), dimethylethanolamine (from dimethyl-amine and EO), and diethylethanolamine (from diethylenamine and EO). 

The work of Nyc and associates on the lipids of Neurospora crassa is of particular interest in relation to the bios3mthesis of lecithin. The phospholipid of a choline-requiriug mutant contains the phosphatidyl esters of both mono- and di-methylaminoethanol (Hall and Nyc 1961). Nutritional studies with appropriate mutants of this organism have shown that lecithin may be formed (a) from choline by the cytosine nucleotide pathway (Reactions 11 and 12), (b) from phosphatidyl ethanolamine by the methylation pathway (Reactions 13,14 and 15) and (c) from mono- and di-methylaminoethanol by the incorporation of the base into lipid, presumably by way of CDP-intermediates, followed by methylation. The relative contributions of these pathways can be influenced by mutations and by nutritional supplementation of the culture medium (Crocken and Nyc 1964). 

Detection methods. - Various metallic wires were investigated for use in constant-potential amperometric detection of carbohydrates in HPAEC eluates. Copper proved best, and when conditions were optimized, picomole amounts of various sugars could be detected. Conditions fcH-post-column generation of fluorescence by reaction of mono- to tri-saccharides with an ethanolamine-boric acid reagent were optimized, and applied to the h.p.Lc. analysis (anion-exchanger, alkaline aq. borate eluant) of mono- and di-saccharides in wine. The detection of disaccharides was markedly improved if a post-column acid-catalysed hydrolysis reactor was added prior to detection. ... 

The solvents most used in carbon dioxide removal from ammonia synthesis gas can be characterized according to the nature of the absorption process. Chemical absorption, i.e. processes where the carbon dioxide reacts with the solvent by a chemical reaction which is reversed in the solvent regeneration stage, is most often based on the use of alkanolamines, mainly MEA (mono-ethanolamine) [273], or hot solutions of potassium carbonate [274] as solvents. 

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