Ethyl acetate as extraction solvent

Recovery studies for (+)-catechin and (-)-epicatechin in synthetic wine solutions performed by HPLC revealed differences between these stereoisomers 79 % (-)-epicatechin was recovered compared to 97 % (+)-catechin [176]. We evaluated the use of ethyl acetate as extraction solvent in the analysis of extracts of hawthorn herb. Four subsequent extractions were performed and determinations were carried out in triplicate. From the total contents only 82 % (-)-epicatechin and 43 % procyanidin Cl could be recovered in the ethyl acetate extracts. The proportions of procyanidins B2 and B5 in the ethyl acetate extracts could not be determined because the peaks in the water phases were superimposed by matrix components. LC-MS (liquid chromatography mass spectrometry) analysis of the water phases however proved the presence of procyanidins B2, B5 and Cl besides other dimeric, trimeric and tetrameric procyanidins (see Fig. (4)).3... 

Szolar, O. H., Rost, H., Braun, R., and Loibner, A. P., Analysis of polycyclic aromatic hydrocarbons in soil minimizing sample pretreatment using automated Soxhlet with ethyl acetate as extraction solvent. Anal. Chem., lA, 2379-2385, 2002. 

Griswold, Chu, and Winsauer [Ind, Eng, Chem, 41, 2352 (1949)] provide very complete data on the liquid-liquid and vapor-liquid equilibria in the system ethanol-ethyl acetate-water. Design a plant and solvent-recovery system for the recovery of 99.8% ethanol from 50,000 gal./day of a 5% solution in water, using ethyl acetate as extracting solvent. Solvent concentration in the raffinate phase is to be no greater than 0.001%. 

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