Dipa

Solvents used for hydrogen sulfide absorption include aqueous solutions of ethanolamine (monoethano1 amine, MEA), diethanolamine (DEA), and diisopropanolarnine (DIPA) among others ... 

Activated tertiary amines such as triethanolamine (TEA) and methyl diethanolamine (MDEA) have gained wide acceptance for CO2 removal. These materials require very low regeneration energy because of weak CO2 amine adduct formation, and do not form carbamates or other corrosive compounds (53). Hybrid CO2 removal systems, such as MDEA —sulfolane—water and DIPA—sulfolane—water, where DIPA is diisopropylamine, are aqueous alkaline solutions in a nonaqueous solvent, and are normally used in tandem with other systems for residual clean-up. Extensive data on the solubiUty of acid gases in amine solutions are available (55,56). 

The Sulfinol process from Shell Development Company is a good example of the physical/chemical type of process. It blends a physical solvent and an amine to obtain the advantages of both. The physical solvent is Sulfolane (tetrahydrothiophene dioxide) and the amine is usually DIPA (diisopropanol amine). The flow scheme is the same as for an amine plant. ... 

In the solution, the amine DIPA is meanwhile able to achieve pipeline quality gas (0.25 grains IT/lOOscf). 

COS, CS2, and mercaptans are removed. CO2 slightly degrades DIPA, but reclaiming is easy. ... 

Six potential MSAs should be simultaneously screened. Riese include absoiption in water. Si. adsorption onto activated carbon, Sj, absorption in chilled methanol, S3, and the use of the following reactive solvents diethanolamine (DEA), S4, hot potassium carbonate, Sj, and diisc ir ranolamine (DIPA), S. ... 

Chemical solvents Monoethanol amine (MEA) Diethanol amine (DEA) Methyldiethanol amine fMDEA) Diglycol amine (DGA) Diisopropanol amine (DIPA)... 

Diisopropanolamine Systems. Diisopropanolamine (DIPA) is a secondary amine used in the Shell ADIP process to sweeten natural gas. DIPA systems are similar to MEA systems but offer the following ad an-tages carbonyl sulfide (COS) can be removed and regenerated easily and the system is generally noncorrosive and requires less heat input. 

One feature of this process is that at low pressures DIPA will preferentially remove H2S. As pressure increases the selectivity of the proee s decreases. The DIPA removes increasing amounts of COt as well as the HiS. Therefore, this system can be used either selectively to remove ff-S or to remove both COt and H S. 

Licensed by Shell the Sulfinol process combines the properties of a physical and a chemical solvent. The Sulfinol solution consists of a mixture of sulfolane (tetrahydrothiophene 1-1 dioxide), which is a physical solvent, diisopropanolamine (DIPA), and water. DIPA is a chemical solvent that was discussed under the amines. 

The physical solvent sulfolane provides the system with bulk removal capacity. Sulfolane is an excellent solvent of sulfur compounds such as H2S, COS, and CS2. Aromatic and heavy hydrocarbons and CO2 are soluble in sulfolane to a lesser degree. The relative amounts of DIPA and sulfolane are adjusted for each gas stream to custom fit each application. Sulfinol is usually used for streams with an H2S to CO2 ratio greater than 1 1 or where it is not necessary to remove the CO2 to the same levels as is required for H2S removal. The physical solvent allows much greater solution loadings of acid gas than for pure amine-based systems. Typically, a Sulfinol solution of 40% sulfolane, 40% DIPA and 20% water can remove 1.5 moles of acid gas per mole of Sulfinol solution. 

The chemical solvent DIPA acts as secondary treatment to remove H2S and CO2. The DIPA allows pipeline quality residual levels of acid gas 10 be achieved easily. A stripper is required to reverse the reactions of the DIPA w ith CO2 and H2S. This adds to the cost and complexity of the sys... 

A reclaimer is also required to remove oxazolidones produced in a sule reaction of DIPA and CO2. 

Developed by Allied Chemical Company, this process is selective toward removing sulfur compounds. Levels of CO2 can be reduced bv annroximately 85%. This process may be used economically when there a ligh acid-gas partial pressures and the absence of heavy ends in iJic gas., but it will not normally meet pipeline gas requirements. This proc also removes water to less than 7 Ib/MMscf. DIPA can be added to I... 

The types of equipment and the methods for designing the equipment are similar for both MEA and DEA systems. For other amine systems such as SNPA-DEA, Fluor Econamine (DGA), and Shell ADIP (DIPA) the licensee should be contacted for detailed design information. 

This new impurity proved to be derived from the Pd-catalyzed oxidation of DIPA to the enamine via P-hydride elimination. In fact, mixing Pd(OAc)2 with DIPA in DMF-d7 readily formed Pd black along with two species, primary amine and acetone, presumably derived from the enamine through hydrolysis. The resulting enamine or acetone then underwent a coupling reaction with iodoaniline 28. Heterocyclization through the arylpalladium(II) species provided 2-methyl indole 71, as shown in Scheme 4.19. 

Absorbents based on a variety of amines are by far the most common. Amines that have been used include monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diisopropanolamine (DIPA), methyl diethanolamine (MDEA), and digly-colamine (DGA). C02 is typically absorbed at 80-140°F temperature and up to 1000 psig pressure by chemically reacting with the basic amine functional group in the absorbent, for example, primary amine, MEA, reacts with C02 by the following reaction forming a carbamate salt ... 

Adip [Possibly an acronym of DIPA, di-isopropanolamine] A process for removing hydrogen sulfide, mercaptans, carbonyl sulfide, and carbon dioxide from refinery streams by extraction into an aqueous solution of di-isopropanolamine or methyl diethanolamine. Developed and licensed by the Shell Oil Company, Houston, TX. More than 320 units were operating in 1992. 

V,lV-Diisopropylethylamine, 2 549t Diisopropanolamine (DIPA) physical properties of, 2 1231 specifications, 2 132t... 

DIPA Shell ADIP 90-130 Not highly sensitive Yes, <10 ppmv Partial removal of COS (some mercaptans) Yes. normally 30-90% removal... 

DIPA) and methyldiethanolamine (MDEA) have also been employed. Earlier, Atwood et al. (J 5) proposed a thermodynamic model for the equilibria in I S+alkanol-amine+H20 systems. The central feature of this model is the use of mean ionic activity coefficient. The activity coefficients of all ionic species are assumed to be equal and to be a function only of ionic strengths. Klyamer and Kolesnikova ( 1j[) utilized this model for correlation of equilibria in C02+alkanol-amine+H O systems and Klyamer et al. (J 7) extended it to the H2S+C02+alkanolamine+H20 system. The model is restricted to low pressures as the fugacity coefficients are assumed unity and it has been found that the predictions are inaccurate in the four-component system since the activity coefficients are not equal when a number of different cations and anions are present. 

This procedure could not be employed for diisopro-panolamine (DIPA) solutions since data were available only for one amine concentration at two temperatures. 

In this case data for mixtures of H2S+CO2+DIPA+H2O were used together with the data for H2S+DIPA+H2O and CO2+DIPA+H2O to obtain the interaction parameters and equilibrium constants. The results are shown in Figures 1 and 2 to be in good agreement with the experimental data ( 3). In this case, however, in contrast to the case of MEA, the predictions use parameters evaluated from data for the four component system. 

In the SCOT process, the sulfur compounds in the Claus tail gas are converted to hydrogen sulfide by heating and passing it through a cobalt-molybdenum catalyst with the addition of a reducing gas. The gas is then cooled and contacted with a solution of diisopropanolamine (DIPA) that removes all but trace amounts of hydrogen sulfide. The sulfide-rich diisopropanolamine is sent to a stripper, where hydrogen sulfide gas is removed and sent to the Claus plant. The diisopropanolamine is returned to the absorption column. 

An electrostatic potential difference, called the inner potential difference, arises across the interface of two contacting phases. This inner potential difference consists of a potential gA/ac) due to an interfacial charge (charge on both sides of the interface), Oa/b> aiid a potential gj /snip) due to an interfacial dipole, dipA/B, as shown in Eqn. 4-3 ... 

Obviously, the interfacial charge differs from the initial (before contact) surface charges oa and ob (oa/b " Oa + ob) and the interfacial dipole dipA/s is not the same as the arithmetic sum of the initial surface dipoles igtjaibt) XA(dip)-Xadip)) Thus, it follows that both the inner and the outer potential differences, A( >a/b and Ai a , between the two contacting phases are not the same as those and Atp A/B before the contact. As a result, Eqn. 4-2 yields Eqn. 4-4 ... 

DIPA See diisopropanolamine. dip-o or de T pe a dipentene org chem A racemate of limonene. dT pen,ten dipentene glycol See terpin hydrate. dT pen.ten glT,k6l dipentene hydrochloride See terpene hydrochloride. dT pen,ten,hT-dr3 kl6r,Td ) diphacinone orgchem C23H16O3 A yellow powder with a melting point of 145-147°C used to control rats, mice, and other rodents acts as an anticoagulant. do fas-3,non ... 

Fig. 8. Part of an ESI mass spectrum of hyperbranched polyesteramides based on HHPA and diisopropanolamine A = DIPA, D = HHPA...

Molar ratio DIPA/HHPA Mjj calculated (g/mol) Mji measured (PS standard)... 

Synonyms AI3-15345 BRN 0605284 CCRIS 6235 DIPA EINECS 203-558-5 7V-(1-Methyl-ethyl)-2-propanamine NSC 6758 UN 1158. 

Dioxybenzene, see p-Quinone Dioxyethylene ether, see 1,4-Dioxane DIPA, see Diisopropylamine... 

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