Propylene carbonate as solvent

Dihydro-5,10-dimethylphenazine (171) exhibits two successive reversible one-electron oxidation steps in acetonitrile (Fig. 9) or propylene carbonate as solvents.178 When the compound is electrolyzed in a more nucleophilic solvent, however, the second oxidation is... 

An optimized and reproducible synthesis in propylene carbonate as solvent and in the absence of olefin led to the isolation of ca. 880 mg of 3.8 0.6nm Ir(0) 2,ooo nanoclusters determined as [(Bu4N)] ii,oooNa s oooIt 2,ooo(P4W3o-Nb60i23) i,ooo(C4H603),s,ooo (C4H6O3 = propylene carbonate Scheme 4). ... 

Alkyl-substituted pyrroles are not easy to synthesize and relatively few reports on poly (3-alky Ipyrrolejs have been published [213-216]. These polymers are much more conductive than the corresponding poly(A -substituted-pyrrole)s and, under some selected experimental conditions (propylene carbonate as solvent and PF,- as counterions), even more conductive (270 S cm ) than PP itself [215]. 

Propylene carbonate as solvent 20, 413 suppl. 26 Protection, blocking, masking... 

Table 2 Kinetic parameters for complex formation a/ Ni in propylene carbonate as solvent...

This process uses propylene carbonate as a physical solvent to remove CO2 and H2S. Propylene carbonate also removes C2+ hydrocarbons, COS, SO2, CS2, and H2O from the natural gas stream. Thus, in one step the natural gas can be sweetened and dehydrated to pipeline quality. In general, this process is used for bulk removal of CO2 and is not used to treat to less than 3% CO2, as may be required for pipeline quality gas. The system requires special design features, larger absorbers, and higher circulation rates to obtain pipeline quality and usually is not economically applicable for these outlet requirements. 

Upon variation of the stirring velocity between 500 and 1500 rpm the conversion of the olefin remained at the same high level and the selectivity to the linear aldehyde also remained constant. Obviously there is no mass transfer limitation in this two-phase reaction system. In comparison to the single-phase reaction in propylene carbonate as the only solvent [23], the selectivity decreases from 95% to 70%, which can be explained by the high concentration of the non-electron-donating solvent dodecane in the propylene carbonate phase. The presence of the dodecane leads to a decrease of the isomerization velocity, which results in a lower hnearity of the formed aldehydes. 

Organic solvents can also be classified according to their ability to accept or transfer protons (i.e., their acid-base behavior) [20,21]. Amphiprotic solvents possess donor as well as acceptor capabilities and can undergo autoprotolysis. They can be subdivided into neutral solvents that possess approximately equal donor and acceptor capabilities (water and alcohols), acidic solvents with predominantly proton donor properties (acetic acid, formic acid), and basic solvents with primarily proton acceptor characteristics (formamide, N-methylformamide, and N,N-dimethylformamide). Aprotic solvents are not capable of autoprotolysis but may be able to accept protons (ACN, DMSO, propylene carbonate). Inert solvents (hexane) neither accept nor donate protons nor are they capable of autoprotolysis. 

As can be observed, in the EC/propylene carbonate mixed solvent, the composition of the mixture is the same that the composition observed in the first solvation sphere, thus no preferential solvation is detected. Mixed with chloroform, there is a clear preference of lithium ions towards EC. On the contrary, Li" is preferentially solvated by water in... 

Lafferty and Heinzle [294] described an extraction method using ethylene or propylene carbonate as extracting solvent for PHB from Alcaligenes eutrophus H 16. PHB is soluble in concentrations up to nearby 200 g/L at a temperature of 120 °C in these solvents, whilst at 100 °C solubility is as low as 2 g/L only. Biomass was contacted in a plug flow extractor at 120 °C, residual biomass was removed by a centrifugation step at the same temperature, and PHB was precipitated then by lowering the temperature to 95 °C and removed fy pressure filtration. The extraction solvent was recirculated back to the extractor, remaining solvent was removed from the product by a simple hot water extraction. 

A PAN based GPE has been investigated by Akashi and coworkers [2]. They use the solvent mixture of EC/PC (propylene carbonate) as plasticizers andliPFe as a sustaining salt, and the suitable combination ratio of PAN / solvent / salt... 

Dindore et al. [41] provides an extensive study on manbrane-solvent combination for CO2 removal in gas-liquid membrane contactors. They highlighted that the possibility of membrane wetting is primarily governed by the membrane pore size, surface tension of the liquid and the mutual interactions of liquid and membrane materials signified by contact angle. Dindore et al. [41] concluded that the combination of PP membrane and propylene carbonate as liquid absorbents is the best option for further research. However, the study was limited to PTre membrane and no comparison was made with the other types of membranes. 

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