Ethanolamine processes Ethanolamines

One of the principal aspects of refinery gas cleanup is the removal of acid gas constituents, ie, carbon dioxide, CO2, and hydrogen sulfide, H2S. Treatment of natural gas to remove the acid gas constituents is most often accompHshed by contacting the natural gas with an alkaline solution. The most commonly used treating solutions are aqueous solutions of the ethanolamines or alkah carbonates. There are several hydrogen sulfide removal processes (29), most of which are followed by a Claus plant that produces elemental sulfur from the hydrogen sulfide. 

Consumption of ethanolamines ia the United States has changed dramatically since the 1960s. Consumption ia gas conditioning appHcations has peaked and chemical processing intermediates (captive use for ethyleneamine and surfactant appHcations) has increased significantly. 

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]. 

The precipitated chromic hydroxide and sulfur are discarded. This process is used to purify carbon dioxide from fermentation ia the Reich process and as a final cleanup after the alkaU carbonate or ethanolamine recovery processes (22,23). 

Ethylene oxide [75-21-8] was first prepared in 1859 by Wurt2 from 2-chloroethanol (ethylene chlorohydrin) and aqueous potassium hydroxide (1). He later attempted to produce ethylene oxide by direct oxidation but did not succeed (2). Many other researchers were also unsuccesshil (3—6). In 1931, Lefort achieved direct oxidation of ethylene to ethylene oxide using a silver catalyst (7,8). Although early manufacture of ethylene oxide was accompHshed by the chlorohydrin process, the direct oxidation process has been used almost exclusively since 1940. Today about 9.6 x 10 t of ethylene oxide are produced each year worldwide. The primary use for ethylene oxide is in the manufacture of derivatives such as ethylene glycol, surfactants, and ethanolamines. 

Many accidents occur because process materials flow in the wrong direction. Eor example, ethylene oxide and ammonia were reacted to make ethanolamine. Some ammonia flowed from the reactor in the opposite direction, along the ethylene oxide transfer line into the ethylene oxide tank, past several non-return valves and a positive displacement pump. It got past the pump through the relief valve, which discharged into the pump suction line. The ammonia reacted with 30m of ethylene oxide in the tank, which ruptured violently. The released ethylene oxide vapor exploded causing damage and destruction over a wide area [5]. A hazard and operability study might have disclosed the fact that reverse flow could occur. 

Corti and Manfrida [2] have also done detailed calculations of the performance of plant A2. They drew attention to the need to optimise the amines blend (including species such as di-ethanolamine and mono-ethanolamine) in the absorption process, if a removal efficiency of 80% is to be achieved and in order to reduce the heat required for regenerating the scrubbing solution. Their initial estimates of the penalty on efficiency are comparable to those of Chiesa and Consonni (about 6% compared with the basic CCGT plant) but they emphasise that recirculation of water from... 

Write a balanced, stoichiometric reaction for the synthesis of phosphatidylethanolamine from glycerol, fatty acyl-CoA, and ethanolamine. Make an estimate of the AG° for the overall process. 

CO2 is also recovered economically from the flue gases resulting from combustion of carbonaceous fuels, from fermentation of sugars and from the calcination of limestone recovery is by reversible absorption either in aqueous Na2COi or aqueous ethanolamine (Girbotol process). 

Ethanolamines are important absorbents of acid gases in natural gas treatment processes. Another major use of ethanolamines is the production of surfactants. The reaction between ethanolamines and fatty acids... 

This class of aziridine-forming reaction includes the first reaction reported to afford aziridines. In 1888 Gabriel reported that aziridines could be prepared in a two-step process, by chlorination of ethanolamines with thionyl chloride, followed by alkali-induced cyclization [75]. Wenker subsequently reported that heating of 600 g of ethanolamine with more than 1 kg of 96 % sulfuric acid at high temperature produced P-aminoethyl sulphuric acid 282 g of it was distilled from aqueous base to give 23 g of aziridine itself, the first preparation of the parent compound in a pure condition [76]. Though there is no evidence to substantiate the hypothesis, the intermediate in these reactions is perhaps a cyclic sulfamidate (Scheme 4.51). 

Also the impact of various reaction parameters on enzymatic synthesis of amide surfactants from ethanolamine and diethanolamine has been studied, although the possibilities of acyl migration are not investigated. However, it was found that the selectivity of the reaction depended on the solubility of the product in the solvent used, and that the choice of solvent was critical to obtain an efficient process [17]. 

Recently, an environmentally benign and volume efficient process for enzymatic production of alkanolamides has been described where CALB catalyzes the amidation of lauric acid and ethanolamine in the absence of solvent, at 90 °C, to keep the reactants in a liquid state and to remove the water [18]. The enzyme was both very active and stable under the reaction conditions, with about half of the activity remaining after two weeks, obtaining the final amide with a 95% yield (Scheme 7.6). 

The oxidative dehydrogenation of ethanolamine over skeletal copper catalysts at temperatures, pressures and catalyst concentrations that are used in industrial processes has been shown to be independent of the agitation rate and catalyst particle size over a range of conditions. A small content of chromia (ca. 0.7 wt %) provided some improvement to catalyst activity and whereas larger amounts provided stability at the expense of activity. 

Figure 1.124 Aldehyde groups may be blocked with Tris or ethanolamine using a reductive amination process.

This process probably occurs in vivo because the adduct of ethanolamine and p-hydroxyphe-nylacetaldehyde is abundant in the phospholipids of LDL exposed to activated neutrophils and tyrosine. 

AMISOL A process for removing sulfur compounds and carbon dioxide from refinery streams by absorption in methanol containing mono- or di-ethanolamine and a proprietary additive. Developed by Lurgi, Germany, in the 1960s and first commercialized in the early 1970s. 

In case (1), the reaction is used for the removal of an undesirable substance from a gas stream. In this sense, the process is commonly referred to as gas absorption with reaction. Examples are removal of H2S or CO, from a gas stream by contact with an ethanolamine (e g., monoethanolamine (MEA) or diethanolamine (DEA)) in aqueous... 

From a separation-process point of view, a fluid-fluid reaction is intended to enhance separation (e.g., preparation of feed for a subsequent process step, product purification, or effluent control for environmental protection). Examples include the use of ethanolamines for the removal of H2S and C02 (reactions (A) and (B) in Section 9.2), the removal of SO, by an aqueous stream of a hydroxide, and absorption of 02 by blood or desorption of C02 from blood. A solid catalyst may be involved as a third phase, as in hydrodesulfurization in a trickle-bed reactor. 

Finally PC is made by releasing the CMP group in the process of fusing phosphocholine to diacylglycerol (DAG) by the enzyme CDP-choline 1,2-diacylglycerol choUnephosphotransferase (CPT McMaster and Bell, 1997). One cloned isoform of CPT seems specific for CDP-choUne, whereas another CPT also can synthesize PE from CDP-ethanolamine and DAG (Henneberry and McMaster, 1999 Heimeberry et al., 2000). 

Pyrimido[l,3]oxazines are reactive toward amines anhydride 121 undergoes ring opening and decarboxylation on treatment with ethanolamine to give the amide 122 <1996MI459>. The reactions of amide 123 <2002MI10> with amines to form pyrimido[5,4- pyrimidines have already been mentioned, while the equivalent process with pyr-imido[5,4- ]oxazinium salt 124 is discussed in CHEC-II(1996) <1996CHEC-II(7)737>. 

Ammonia is formed in the reaction. Since the ammonia and ethylenediamine cannot both be formed from the same molecule of N-hydroxyethylethylenediamine, the best explanation is that the ammonia is formed by a reaction sequence entirely similar to the mechanism proposed above, except that the oxygen now attacks the carbon adjacent to the primary nitrogen of the ethylenediamine group of the coordinated N-hydroxyethylethylenediamine. Such a process would result in formation of ethanolamine. The presence or absence of ethanolamine in the reaction mixture could not be ascertained, because no method was found to detect the predicted amount of ethanolamine in the presence of a much larger amount of N-hydroxyethylethylenediamine. 

In many cases, the difference between these potentials—the window of operation without electrochemical decomposition of the solvent—is 3-4 V. In the aqueous case, it may in practice be as little as 1.5 V. On the other hand, even sodium can be electrodeposited from a solution of sodium acetate in ethanolamine. These advantages are countered by three factors that must be considered before a nonaqueous electrodeposition process is chosen as the best solution to co-deposition of H (Section 4.8.3). 

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