Aqueous amine solutions

So you can see that to make MDA or MDMA using either NH3 or MeNH2 one is going to have to think of a way to keep them in the fray. Strike s first impulse is to dissolve the amine in a solvent. But what solvent And would the reaction even work in any solvent Rhodium thinks that maybe an aqueous amine solution would work considering the clay is moistened with water anyway. 

Fig. 15. Schematic of the interfacial polymerization process. The microporous film is first impregnated with an aqueous amine solution. The film is then treated with a multivalent cross-linking agent dissolved in a water-immiscible organic fluid, such as hexane or Freon-113. An extremely thin polymer film...

The present method utilizes dichlorocarbene generated by the phase-transfer method of Makosza4 and Starks.5 The submitters have routinely realized yields of pure distilled isocyanides in excess of 40%.6 With less sterically hindered primary amines a 1 1 ratio of amine to chloroform gives satisfactory results. Furthermore, by modifying the procedure, methyl and ethyl isocyanides may be prepared directly from the corresponding aqueous amine solutions and bromoform.7 These results are summarized in Table I. 

AMINEX A process for removing hydrogen sulfide and carbon dioxide from gas and LPG streams, by circulating an aqueous amine solution through bundles of hollow fibers immersed in them. Developed in 1991 by the Merichem Company, Houston, TX. 

The absorption of carbon dioxide into aqueous amine solutions has been investigated by Danckwerts and McNeil(42) using a stirred cell. It was found that the reaction proceeded... 

Danckwerts, P. V. and McNeil, K. M. Trans. Inst. Chem. Eng. 45 (1967) 32. The absorption of carbon dioxide into aqueous amine solutions and the effects of catalysis. 

The equilibria are readily reversed by heating and the salt loaded aqueous amine solutions can be made to release the carried H2S and CO2 after separation from the hydrocarbon gas being sweetened. 

Figure 3.20 Schematic of the interfacial polymerization process. The microporous film is first impregnated with an aqueous amine solution. The film is then treated with a multivalent crosslinking agent dissolved in a water-immiscible organic fluid, such as hexane or Freon-113. An extremely thin polymer film forms at the interface of the two solutions [47]. Reprinted from L.T. Rozelle, J.E. Cadotte, K.E. Cobian, and C.V. Knopp, Jr, Nonpolysaccharide Membranes for Reverse Osmosis NS-100 Membranes, in Reverse Osmosis and Synthetic Membranes, S. Sourirajan (ed.), National Research Council Canada, Ottawa, Canada (1977) by permission from NRC Research Press...

CO2 Absorption by Aqueous Amine Solutions 9.5.3.1 Chemical System... 

A 1M aqueous amine solution was placed in a two-necked flask, through which CO2 was bubbled with stirring for 1 hour at a flow rate of 50 ml/min at 40 °C under 1 atm. After the end of COj bubbling, the solution was heated to 100 °C and kept at this temperature for an additional hour. The amount of CO remaining in the amine solutions at 40 °C and 100 °C was determined by an apparatus SHIMADZU TOC-10B and was shown here as the loading capacity in mol COg/mol amine (%). Similar determinations of CO2 loadings were made under a CO2 partial pressure of... 

The thermodynamic arguments of this paragraph have been elaborated by Copp and Everett, and the qualitative conclusions are confirmed by recent work on aqueous amine solutions. ... 

Aqueous amine solutions are the most common chemical solvents for H S removal, wherein the weakly acidic H S is neutralized by the alkaline amine solution. HjS reacts rapidly and directly with 1°, 2°, or 3° amines to form the bisulfide (HS") anion and a protonated ammonium cation (Fig. 6.1a) [1, 2], The bisulfide anion can then react with another amine to form the sulfide (S ) anion and another equivalent of the protonated ammonium cation (Fig. 6.1b). 

They are formed while CO2 capture from (flue) gases using aqueous amine solutions. 

Thinking was turned towards the third option and tenders were called for a 35 t/day liquid SO2 plant. Bids were received for two radically different technologies namely, a conventional partial condensation process using ammonia and absorption using an aqueous amine solution. 

Solubility of CO2 in aqueous amine solutions a study to select solvents for carbon capture from natural-gas power plant... 

MEA and PZ were purchased from VWR, and DMAE and AMP were supplied by Acros Organics. All of the tested amines were of at least 99 mass% purity. Aqueous amine solutions were prepared gravimetrically, and C02-saturated solutions were prepared from these by bubbling CO2 through them at ambient pressure in a gas washing bottle. Partially loaded solutions were obtained by diluting C02-saturated solutions with fresh amine solution in the desired ratios. CO2 loading a.co was determined by GC analysis with an estimated uncertainty of 2%. 

To facilitate engineering calculations, it is essential to know the physical properties of solvents, and so properties such as the density and viscosity of aqueous amine solutions have been widely studied in the hterature. However, veiy few literature data are available for C02-loaded aqueous amine systems. Our study therefore focuses on the effect of dissolved CO2 on key thermophysical properties of aqueous amine solutions. 

Table 1. Comparison between absorption capacity of CO2 in aqueous amine solution from this work and literature.

In the past, steacJy-state methods have been used for determining equilibrium and rate parameters (solubilities, rate constants, diffusivities,. ..) for gas-liquid process design (1) of recent industrial interest is the selective separation of acid gases by aqueous amine solutions (SO, H S or CO ). ... 

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