Diethanolamine solutions vapor pressure

Total Vapor Pressures of Aqueous Diethanolamine Solutions (weight % of amine)... 

Vapor Pressure vs. Temperature for Aqueous Solutions of Diethanolamine... 

FAB was introduced in 1981 by Barber et al. [17, 18]. In FAB [17-20], the analyte of interest is dissolved in an appropriate matrix solvent, such as glycerol, diethanolamine and other rather polar solvents with low vapor pressure. The solution is applied as a thin film onto a metal target, which subsequently is brought in a beam of high-energy particles (see Fig. 7.2). FAB differed from the already existing SIMS method [21] in two experimental aspects, i.e., the use of abeam of atoms instead of a beam of ions as primary particles, and the use of a hquid matrix for dissolving the... 

One of the most widely used commercial absorption processes is the removal of CO2 or HgS from a gas stream by contacting it with a solution of monoethanolamine or diethanolamine. Both of these solutions are alkaline and combine chemically with 14 mol of acid gas per mol of amine. Although a chemical combination exists, still even at equilibrium, the acid gas exhibits a vapor pressure above the solution. Because this vapor pressure of the absorbed acid gas increases rapidly with temperature increase, it is possible to regenerate the rich amine solution by stripping the heated solvent. 

Figure 2-30. Vapor pressure of CO2 vs. CO2 conceniration in 5 N diethanolamine solution.

Figure 2-34. Effect of CO2 on vapor pressure of H2S over 2 N diethanolamine solution containing both CO2 and H2S.

Hgure 3-20. Vapor pressure of monoethanolamine and diethanolamine over aqueous solutions. Chemetron Coiporation and Texaco ( emical... 

A schematic flow diagram of the unit is shown in Figure 3-33. A solution of 48 wt% potassium hydroxide is added to the contaminated diethanolamine before it enters the top of a packed tower where it is contacted with superheated steam rising from the reboiler. Essentially all of the amine and water is vaporized, and the product is withdrawn at a point below the packed section into a condenser, which is held at a slightly lower pressure than that prevailing in the reboiler. A steam jet is used to maintain the required pressure. The salts drop into the reboiler and melt at 420 to 440°F, and any residual diethanolamine is flashed off. The temperature of the diethanolamine-water vapor withdrawn is 300 to 375°F. The temperatures in the column and reboiler are sufficient to vaporize practically all the amine without decomposition. Heat is supplied by circulating oil at 600°F through the reboiler tubes. Recovery of 90% of reusable diethanolamine is claimed. 

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