Improved means for the refining of crude extracts and mixtures

摘要

A method of refining a crude extract of a material of natural origin is provided and comprises: a. contacting the crude extract with a first solvent comprising a blend of a first liquefied gas having a first solvating range and a second liquefied gas having a second solvating range so as to form a solution of a first fraction of components of the crude extract in the first solvent; b. separating the solution of step (a) from the crude extract; c. contacting the remainder of the crude extract with a second solvent comprising an at least quantitatively different blend of liquefied gases to that of step (a) so as to form a solution of a second fraction of the components of the crude extract in the second solvent; and d. removing the first and second solvents from the solutions to provide refined first and second fractions of the crude extract. The first liquefied gas is preferably an iodofluorocarbon. The second liquefied gas is preferably an hydrofluorocarbon.