Alkanolamines Ethanolamines

Diethanolamine is metabolized by biosynthetic routes common to endogenous alkanolamines (ethanolamine and choline) and incorporated into phospholipids. It is excreted predominantly unchanged with a half-life of approximately one week in urine. In the absence of sodium nitrite, no conversion to TV-nitrosodiethanolamine is observed. Diethanolamine competitively inhibits the cellular uptake of choline in vitro and hepatic changes in choline homeostasis, consistent with choline deficiency, are observed in vivo. 

Mining. Numerous patents have advocated the use of alkanolamines in mining appHcations. Triethanolarnine has been used as a depressent in the flotation of copper (164), in the electrotwinning of gold (165), and as an aid in the froth flotation of nickel ores. Phosphate ore flotation has been improved through the use of a fatty acid condensate with ethanolamine (166). Beneficiation of tin ore has been accompHshed using fatty acid alkanolamides (167). 

High yields of optically active cyanohydrins have been prepared from hydrogen cyanide and carbonyl compounds using an enzyme as catalyst. Reduction of these optically active cyanohydrins with lithium aluminum hydride in ether affords the corresponding substituted, optically active ethanolamine (5) (see Alkanolamines). 

Ethanolamines. These are produced by the reaction of ethylene oxide and ammonia (see Alkanolamines). Approximately one-third of the production is used in detergents. Other appHcations include natural gas purification, cosmetics, metalworking, textiles, and chemical intermediates (282). 

ESTERS OF AMINOBENZOIC ACIDS AND ALKANOLAMINES a. Derivatives of Ethanolamine... 

For many years such media have been based on strong salt solutions, e.g. calcium chloride brines. Sodium dichromate has been used (seep. 17 26), but recently other inhibitors have been claimed to be effective. One patent quotes N-alkyl-substituted alkanolamines, e.g. 2-ethyl ethanolamine -I- BTA at pH A mixture of hydrazine hydrochloride -i- BTA has been claimed as well as a mixture of gelatin -h triethanolamine -h potassium dihydrogen phosphate . Other examples are to be found in the patent literature and the above are quoted to illustrate the diversity of chemicals that may be used. 

Alkanolamines Aminoethylethanolamine Diethanolamine Diethylethanolamine Dimethylethanolamine Ethanolamine Propanolamine Triethanolamine... 

The reaction under pressure of ethanolamine and urea, preferably in excess ammonia, was investigated only briefly. It was found to proceed rapidly to produce yields of approximately 38%, based upon the alkanolamine, at 300° and about 900 atmospheres pressure. 

Ethylene oxide, propylene oxide, or butylene oxide react with ammonia to produce alkanolamines. The more popular ethanolamines [NH3 h(C2H4OH)h, where n = 1,2,3 monoethanolamine, diethanolamine, and triethanolamine], are derived from the reaction of ammonia with ethylene oxide. 

It should also be noted that absorption has been used to remove contaminants from natural gas streams during processing. In the early 1930s di-ethanolamine was used as an absorbent for both hydrogen sulfide and carbon dioxide.This process became known as the Gerbitol Process. Other alkanolamines such as mono-ethanolamine and di-isopropanolamine have also found wide application. 

ISOBUTENYL METHYL KETONE (141-79-7) Forms explosive mixture with air (flash point 87°F/31°C). Forms unstable peroxides in storage. Violent reaction with strong oxidizers, 2-aminoethanol, chlorosulfonic acid, 1,2-ethanediamine, ethanolamine, nitric acid, sulfuric acid, oleum. Incompatible with strong acids, aliphatic amines, alkanolamines, ethylene diamine. Dissolves some forms of plastics, resins, and rubber. Attacks copper. 

The occurrence of A-nitrodiethanolamine at various levels in all sorts of aqueous fluids in the mechanical industry results primarily from the reaction between alkanolamines and nitrite ions. The alkanolamines, such as di- or tri-ethanolamines (or their derivatives) are used as anticorrosives, lubricants or emulsifiers. The nitrite ions are frequently present in trace amounts or they are intentionally added to inhibit corrosion (metalworking fluids). 

Tlie freezing points of alkanolamines are moderately liigh as shown in Tables 1 and 2. Tlie ethanolamines, monoisopropanolamine and mono-j -butaiiolaiiiinej are colorless liquids at or near room temperature. Di- and tiiisopropanolamine and di- and tii-j -butanolamine are wliite solids at... 

A brief summary of safety and health hazards follows detailed health hazards, however, should be obtained from producers by requesting Material Safety Data Sheets. Proper protective equipment and exposure hazards should be noted before handling any alkanolamine. Detailed toxicological testing is found in the CTFA Chemical Ingredient Review Board Reports on ethanolamines and isopropanolamines (24). 

Petroleum and Goal. The alkanolamines have found wide use in the petroleum industry. The ethanolamines are used as lubricants and stabilizers in drilling muds. Reaction products of the ethanolamines and fatty acids are used as emulsion stabilizers, chemical washes, and bore cleaners (168). Oil recovery has been enhanced through the use of ethanolamine petroleum sulfonates (169—174). Oil—water emulsions pumped from weUs have been demulsifted through the addition of triethano1 amine derivatives. Alkanolamines have been used in recovering coal in aqueous slurries and as coal—oil mix stabilizers (175—177). 

Alkanolamines are used in the manufacture of a variety of pharmaceutical compounds. Some of these products include antitumor agents, anti-inflammatory and allergy agents, and anticonvulsants. The Hterature reports ethanolamine derivatives in the treatment of Alzheimer s disease (216), the treatment of cerebral psychoorganic syndromes (217), and veterinary drugs (218). 

The major use of alkanolamines in agricultural products is as a neutralizer for acidic herbicides. They also contribute increased water solubility, reduced volatility, and more uniform solutions. Various ethanolamines are reported in formulations to improve potato tuber size (219) and enhance the resistance to salt of some crops (220). 

Synonyms 2-Ami noethanol 2-Ami noethyl alcohol p-Aminoethyl alcohol p-Ethanolamine Ethylolamine Glycinol 2-Hydroxyethylamine p-Hydroxyethylamine MEA MELA Monoethanolamine Classification Aliphatic amino alcohol alkanolamine Empirical C2H7NO Formula NH2CH2CH2OH Properties Colorless clear mod. vise, liq. ammoniacal odor misc. with water, alcohol, acetone, glycerin sol. in chloroform si. sol. in benzene m.w. 61.10 dens. 1.012 vapor pressure 0.26 mm Hg m.p. 10.5 C b.p. 170 C flash pt. 93 C autoignition temp. 410 C ref. index 1.4540 pH 12.1 surf. tens. 48.89 dynes/cm dielec, const. 37.72... 

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