The invention concerns a method for purifying a hydroalcoholic feedstock, comprising: a) a step of counter-current liquid-liquid extraction, comprising an extraction section supplied at the top with said hydroalcoholic feedstock and at least one intermediate raffinate fraction from step b) and at the bottom with an extraction solvent, and producing at the top an extraction stream and at the bottom a raffinate, wherein the extraction section is operated at a mean temperature in the extractor of between 10 and 40° C.; b) a counter-current liquid-liquid back-extraction comprising a back-extraction section supplied at the top with an acidic aqueous solution, having a pH between 0.5 and 5.0, and at the bottom with the extraction stream from step a), and producing at the top an extract and at the bottom the intermediate raffinate, wherein the back-extraction section is operated at a mean temperature between 40 and 80° C.

The invention provides a process for refining bio-based propylene glycol, wherein impurities having boiling points close to that of propylene glycol are separated. In this process, C.sub.5-C.sub.20 oleophilic alcohol compounds, C.sub.5-C.sub.20 alkanes and/or C.sub.4-C.sub.20 oleophilic ketone compounds are subjected to azeotropism as an azeotropic solvent together with the bio-based propylene glycol to obtain an azeotrope containing propylene glycol. Then the azeotropic solvent in the azeotrope is separated to obtain a crude propylene glycol which is further purified to obtain propylene glycol.

The invention provides a process for refining bio-based propylene glycol, wherein impurities having boiling points close to that of propylene glycol are separated. In this process, C.sub.5-C.sub.20 oleophilic alcohol compounds, C.sub.5-C.sub.20 alkanes and/or C.sub.4-C.sub.20 oleophilic ketone compounds are subjected to azeotropism as an azeotropic solvent together with the bio-based propylene glycol to obtain an azeotrope containing propylene glycol. Then the azeotropic solvent in the azeotrope is separated to obtain a crude propylene glycol which is further purified to obtain propylene glycol.

The invention provides a process for refining bio-based propylene glycol, wherein impurities having boiling points close to that of propylene glycol are separated. In this process, C.sub.5-C.sub.20 oleophilic alcohol compounds, C.sub.5-C.sub.20 alkanes and/or C.sub.4-C.sub.20 oleophilic ketone compounds are subjected to azeotropism as an azeotropic solvent together with the bio-based propylene glycol to obtain an azeotrope containing propylene glycol. Then the azeotropic solvent in the azeotrope is separated to obtain a crude propylene glycol which is further purified to obtain propylene glycol.

The present invention is directed to a composition for use in recovering an alcohol from an aqueous solution the composition comprising: a) a recovery solution comprising at least one tertiary amine containing compound and at least one enolisable carbonyl; and, b) an aqueous process solution comprising the alcohol, wherein the recovery solution and the aqueous process solution are in direct contact, not miscible and at least a portion of the alcohol migrates from the aqueous process solution into the recovery solution.

The present invention is directed to a composition for use in recovering an alcohol from an aqueous solution the composition comprising: a) a recovery solution comprising at least one tertiary amine containing compound and at least one enolisable carbonyl; and, b) an aqueous process solution comprising the alcohol, wherein the recovery solution and the aqueous process solution are in direct contact, not miscible and at least a portion of the alcohol migrates from the aqueous process solution into the recovery solution.

The present invention is directed to a composition for use in recovering an alcohol from an aqueous solution the composition comprising: a) a recovery solution comprising at least one tertiary amine containing compound and at least one enolisable carbonyl; and, b) an aqueous process solution comprising the alcohol, wherein the recovery solution and the aqueous process solution are in direct contact, not miscible and at least a portion of the alcohol migrates from the aqueous process solution into the recovery solution.

A process is described for the separation of at least one inositol from a carob extract. The carob extract is filtered and demineralized, and has a Brix value greater than 60 and a pinitol content of 5 to 25 wt %. The carob extract is subjected to chromatographic separation which involves at least one passage on a chromatographic resin. This produces an aqueous solution comprising 35 to 70 wt % pinitol and a Brix value of 20 or lower. The aqueous solution is then purified to obtain a purified aqueous solution having a pinitol content of more than 55%.

A process is described for the separation of at least one inositol from a carob extract. The carob extract is filtered and demineralized, and has a Brix value greater than 60 and a pinitol content of 5 to 25 wt %. The carob extract is subjected to chromatographic separation which involves at least one passage on a chromatographic resin. This produces an aqueous solution comprising 35 to 70 wt % pinitol and a Brix value of 20 or lower. The aqueous solution is then purified to obtain a purified aqueous solution having a pinitol content of more than 55%.

The presently claimed invention relates to a process for the recovery of 3-methyl-3-buten- -ol from a stream comprising (Z)-3-methylpent-2-ene-1,5-diol, (E)-3-methylpent-2-ene-,5-diol and 3-methylenepentane-1,5-diol by treating the stream with isobutene and water.