Sulfolane water

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). 

When the products are partially or totally miscible in the ionic phase, separation is much more complicated (Table 5.3-2, cases c-e). One advantageous option can be to perform the reaction in one single phase, thus avoiding diffusional limitation, and to separate the products in a further step by extraction. Such technology has already been demonstrated for aqueous biphasic systems. This is the case for the palladium-catalyzed telomerization of butadiene with water, developed by Kuraray, which uses a sulfolane/water mixture as the solvent [17]. The products are soluble in water, which is also the nucleophile. The high-boiling by-products are extracted with a solvent (such as hexane) that is immiscible in the polar phase. This method... 

On the industrial level, aqueous two-phase systems are used more often than nonaqueous two-phase systems. The Kuraray Co. operates a pilot plant for the hydrodimerization of 1,3-butadiene in a two-phase system with a Pd/tppms catalyst (140). The reaction is carried out in sulfolane-water, from which the products, the octadienols, separate. The final products can be octanol or nonanediol made by subsequent isomerization and hydroformylation. The capacity of the Kuraray process is about 5000 tons/year. 

Acid Dimethyl Sulfoxide Dimethyl Formamide Acetonitrile Sulfolane Water... 

Most polymers belonging to this class are water-soluble only in their protonated form. As a consequence, most potentiometric titrations of these polymers have been performed with OH starting from their hydrochlorides, either in water or in mixed solvents, such as water/dioxane, water/sulfolane, water/acetonitrile 64). Many poly[thio-l-(N,N-dialkyl-aminomethyl)ethylene]s are optically active, and in these cases ORD and CD techniques may be used to study their protonation behaviour, in addition to potentiometric techniques. 

Description Hydrocarbon feed is pumped to the liquid-liquid extraction column (1) where the aromatics are dissolved selectively in the sulfolane water-based solvent and separated from the insoluble non-aromatics (paraffins, olefins and naphthenes). The non-aromatic raffinate phase exits at the top of the column and is sent to the wash tower (2). The wash tower recovers dissolved and entrained sulfolane by water extraction and the raffinate is sent to storage. Water containing sulfolane is sent to the water stripper. 

According to a patent [Y. Tokitoh, T. Higashi, K. Hino, M. Murosawa and N. Yoshimura, US Patent 5 057 631 (1991), to Kuraray Industries] the reaction is conducted with butadiene in sulfolane / water in the presence of Pd(OAc)2 as catalyst precursor and a soluble triarylphosphine (or its phosphonium bicarbonate, which is formed from octadienol itself and carbon dioxide) as ligand. The selectivity to 2,7-octadien-l-ol is 92-94% (TOF > 1000), while the isomeric l,7-octadien-3-ol accounts for another 3 5%. The product is extracted with hexane, while the aqueous sulfolane solution, containing the catalyst ca. 1 mmol/1) and triethylamine, is recycled. In the absence of carbon dioxide, the main product is 1,3,7-octatriene, an open-chain butadiene dimer. 

The process reported here uses a clever combination of the factors that promote catalyst life and efficiency. The soluble phosphine or its phosphonium salt, used in a molar excess of about 50 over palladium, stabilizes the palladium complex in aqueous solution the sulfolane-water solution ensures the solubility of the reactants, while extraction with hexane under CO2 pressure recovers the product with only small contamination by palladium, phosphorus or nitrogen. The phosphine or its phosphonium salt and the ammonium bicarbonate remain in the aqueous solution. Since the TON is good and the solution can be recycled, consumption of palladium is very low. 

Cobalt(II) salts are effective catalysts for the oxidation of 1,2-glycols with molecular oxygen in aprotic polar solvents such as pyridine, 4-cyanopyridine, benzonitrile, DMF, anisole, chlorobenzene and sulfolane. Water, primary alcohols, fatty acids and nitrobenzene are not suitable as solvents. Aldehydic products are further oxidized under the reaction conditions. Thus, the oxidative fission of rram-cyclo-hexane-l,2-diol gives a mixture of aldehydes and acids. However, the method is of value in the preparation of carboxylic acids from vicinal diols on an industrial scale for example, decane-1,2-diol is cleaved by oxygen, catalyzed by cobalt(II) laurate, to produce nonanoic acid in 70% yield. ... 

Figure 1. Effect of the ligand concentration on the telomerization of butadiene with water in sulfolane/water (50 50, wt./wt.) solution containing 2 mM Pd(OAc>2 and 8 wt.% triethylamine, at 75 °C for 1 h under 0.5 MPa CO2.

Figure 3. The effect of the concentration of triethylamine on the rate of telomerization of butadiene with water. In sulfolane/water (80 20) solution containing 2.7 m i Pd(OAc)2 and 54 mM ligand, at 75 °C for 3 h under 1.5 MPa CO2.

In the experiments of Hayes et al. (1975) DMSO was marginally better than DMF or sulfolane for dissolving humic substances (Table 4). In the ESR there was evidence of a higher free radical concentration in DMSO than in either DMF or sulfolane. Because DMSO would not be expected to generate free radicals, it is reasonable to infer from the ESR data that humic components, which are insoluble in the DMF- and sulfolane-water systems, were dissolved in this solvent. Elemental contents were similar for the humic and fulvic acids of the DMSO extracts, and these data infer that the major difference between the two fractions was one of molecular size. However, some fulvic acid materials were observed to precipitate during dialysis, as was noted for the DMF and sulfolane systems. 

As far as is known, the only industrial application of the water-soluble catalyst for the hydroformylation of 5 -functionalized alkenes has been developed by Kura-ray [17]. In this process, 7-octen-l-al is hydroformylated into nonane-1,9-dial, a precursor of nonene-l,9-diol, by using a rhodium catalyst and the monosulfonated tri-phenylphosphine as water-soluble ligand in a 1 1 sulfolane/water system. At the completion of reaction, the aldehydes are extracted from the reaction mixture with a primary alcohol or a mixture of primary alcohol and saturated aliphatic hydrocarbon (cf. Section 6.9). 

Freezing point curve for Sulfolane — water mixtures... 

CONSTANTS, VAPOR PRESSURES, ACTIVITIES, AND HEATS OF MIXING OF SULFOLANE-WATER, SULFOLANE-METHANOL, AND SULFOLANE-ETHANOL MIXTURES. 

Yu, Y.-X. Liu, J.-G. Gao, G.-IL Isobaric vapor-liquid equilibria and excess volumes for the binary mixtures water + sulfolane, water + tetraethylene glycol, and benzene + tetraethylene glycol J. Chem. Eng. Data 2000,45, 570-574... 

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