Diglycolamine

To effectively remove carbonyl sulfide from a gas stream, special alkaline scmbbiag Hquors are used. These contain sodium aluminate or sodium plumbite, or they are made of alkaUes with a hydrolysis catalyst based on Zn, Fe, Ni, or Cu. Diethanolamine, diglycolamine, or other alkanolamines (qv) mixed with water remove carbonyl sulfide from sour, ie, acid-gas-containing, gas streams (25,26) (see Carbon dioxide). 

The diglycolamine (DGA) process also allows high (up to 60 wt % DGA) solvent concentrations for reduced chculation rate and energy requhements. High solvent costs and a higher tendency to absorb heavy hydrocarbons have limited the use of this solvent. 

Diglycolamine Systems. The Fluor Econamine process uses digl> co lamine (DGA) to sweeten natural gas. The active DGA reagent is 2-(2-tunino-ethoxy) ethanol, w hich is a primary amine. The reactions of DG, with acid gases are the same as for MEA. Degradation products from reactions with COS and CS2 can be regenerated in a reclaimer. 

Diglycolamine (DGA), is another amine solvent used in the Econamine process (Fig 1-2). Absorption of acid gases occurs in an absorber containing an aqueous solution of DGA, and the heated rich... 

Therefore a special N-containing ether carboxylate was developed [36] with a high melting point ( 90°C) with a good foam and low hard water sensibility. This is obtained by condensation of a fatty acid (e.g., lauric acid) with diglycolamine, followed by carboxymethylation with NaOH and SMCA, washing out of the reaction mixture with a aqueous solution of a strong acid, separation of the oil layer, and neutralization with NaOH or KOH. The result is an ether carboxylate with exactly 2 EO units with the structure ... 

Other lipophilic groups possibly attached to the maleic acid anhydride are alkanolamides of fatty acids. In this case the variations could be chain length and/or saturation grade of the C chain, the type of alkanolamine (most common are isopropanolamine, monoethanolamine, and diglycolamine), or an etho-... 

The most widely used amine is monoethanolamine (MEA), which is considered as a benchmark solvent because of its high cyclic capacity, significant absorption-stripping kinetic rates at low C02 concentration and high solubility in water. Some other amine-based solvents such as diethanolamine (DEA), triethanolamine (TEA), diglycolamine (DGA), N-methyldiethanol-amine (MDEA), piperazine (PZ), 2-amino-2-methyl-l-propanol (AMP) and N-(2-aminoeth-yl)piperazine (AEP) have also traditionally been utilised. 

Aromex A process for removing aromatic hydrocarbons from petroleum reformate by extrachon with diglycolamine (also called [2-(2-aminoethoxy) ethanol], and DGA). Developed by Howe-Baker Engineers. See also Econamine. 

Econamine A process for removing acid gases from natural gas by selective absorption in diglycolamine (also called [2-(2-aminoethoxy) ethanol], and DGA). Developed by the Fluor Corporation, the El Paso Natural Gas Company, and the Jefferson Chemical Company and widely used. Later versions, developed by Fluor Daniel International, include the Fluor Daniel Econamine and the Econamine FG processes. More than 30 units were operating in 1996. See also Aromex. 

DGA Fluor Econamine diglycolamine 90-130 Not highly sensitive Yes, <4 ppmv COS, CS2 degrades solution Yes, below that normally provided by MEA... 

Alkanolamines. Gas sweetening, ie, removal of hydrogen sulfide and carbon dioxide, using alkanolamines was patented in 1930. Several amine solvents are available as of the mid-1990s. The most widely used are monoethanolamine [141-43-5], diethanolamine [111-42-2], diglycolamine [929-06-6], and methyldiethanolamine [105-59-9]. Amine processes are generally applicable when hydrogen sulfide concentration in the feed gas is relatively low (eg,... 

Stainless steel is used in critical areas where hot carbon dioxide-laden solutions are present. It is reported that antifoam agents (silicones) are used in some cases with this process . Some pressurized wash processes also use diglycolamine to remove sulfur compounds and COj 6. 

Low temperature methanol Dimethyl ethers of polyethylene glycol Di-isopropanolamine dissolved in sulfolane and water Monoethanolamine (MEA) or diglycolamine... 

Common amines used for removing H S from sour natural gas include monoethanolamine (MEA), diglycolamine (DGA), and diethanolamine (DEA) (Fig. 6.2) [1, 2]. 

Martin JL, Otto FD, Mather AE (1978) Solubility of hydrogen sulfide and carbon dioxide in a diglycolamine solution. J Chem Eng Data 23 163-164... 

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