A process for the preparing glycols from a lignocellulosic solid biomass involves contacting the biomass with an organic solvent comprising a low boiling point alcohol and a pre-treatment acid at a temperature in a range from 80 to 220° C. and a pressure in a range from 1 to 50 bara. The resulting mixture, having >20 wt. % water, is separated into a pre-treated solid residue comprising cellulose and a liquid stream comprising dissolved lignin and hemicellulose. The pre-treated solid residue is subjected to a hydrogenolysis reaction, generating a glycols stream, a lights stream, comprising a first portion of organic solvent, and a heavies stream. At least of part of the liquid stream is separated to produce a second portion of organic solvent and a solid residue of lignin and hemicellulose. At least part of the first and second portion of organic solvent is recycled to the contacting step.

A process for preparing glycols from a lignocellulosic solid biomass involves contacting the biomass with an organic solvent comprising a low boiling point alcohol and a pre-treatment acid at a temperature in a range from 80 to 220° C. and a pressure in a range from 1 to 50 bara. The resulting mixture, having less than wt. % water, is separated into a pre-treated solid residue comprising cellulose and a liquid stream comprising dissolved lignin. The pre-treated solid residue is subjected to a hydrogenolysis reaction. generating a glycols stream, a lights stream, comprising a first portion of organic solvent, and a heavies stream. At least part of the liquid stream is separated to produce a second portion of organic solvent and a lignin stream. At least part of the first and second portions of organic solvent is recycled to the contacting step.

A process for preparing glycols from a lignocellulosic solid biomass involves contacting the biomass with an organic solvent comprising a low boiling point alcohol and a pre-treatment acid at a temperature in a range from 80 to 220° C. and a pressure in a range from 1 to 50 bara. The resulting mixture, having less than wt. % water, is separated into a pre-treated solid residue comprising cellulose and a liquid stream comprising dissolved lignin. The pre-treated solid residue is subjected to a hydrogenolysis reaction. generating a glycols stream, a lights stream, comprising a first portion of organic solvent, and a heavies stream. At least part of the liquid stream is separated to produce a second portion of organic solvent and a lignin stream. At least part of the first and second portions of organic solvent is recycled to the contacting step.

The invention provides a process for the separation of a first C3 to C7 diol from a first mixture of C3 to C7 diols. The first mixture is provided to a first distillation column. An extractant is fed to the first distillation column above the first mixture. A stream comprising the first diol and the extractant is removed as a bottoms stream from the first distillation column and subjected to distillation in a second distillation column. A high purity first diol stream is removed from the top section of the second distillation column, while a used extractant stream is removed from the bottom section. The extractant is a C3 to C6 sugar alcohol or mixture thereof. The first diol is a close-boiler to and/or forms an azeotrope with one or more of the other C3 to C7 diols present in the first mixture.

The invention provides a process for the separation of a first C3 to C7 diol from a first mixture of C3 to C7 diols. The first mixture is provided to a first distillation column. An extractant is fed to the first distillation column above the first mixture. A stream comprising the first diol and the extractant is removed as a bottoms stream from the first distillation column and subjected to distillation in a second distillation column. A high purity first diol stream is removed from the top section of the second distillation column, while a used extractant stream is removed from the bottom section. The extractant is a C3 to C6 sugar alcohol or mixture thereof. The first diol is a close-boiler to and/or forms an azeotrope with one or more of the other C3 to C7 diols present in the first mixture.

The present invention relates to the use of a transition metal catalyst TMC1, which comprises a transition metal M selected from metals of groups 7, 8, 9 and 10 of the periodic table of elements according to IUPAC and a tetradentate ligand of formula I wherein R.sup.1 are identical or different and are each an organic radical having from 1 to 40 carbon atoms, and R.sup.2 are identical or different and are each an organic radical having from 1 to 40 carbon atoms, as catalyst in processes for formation of compounds comprising at least one carboxylic acid ester functional group —O—C(═O)— starting from at least one primary alcohol and/or hydrogenation of compounds comprising at least one carboxylic acid ester functional group —O—C(═O)—. The present invention further relates to a process for hydrogenation of a compound comprising at least one carboxylic acid ester functional group —O—C(═O)—, to a process for the formation of a compound comprising at least one carboxylic acid ester functional group —O—C(═O)— by dehydrogenase coupling of at least one primary alcohol with a second alcoholic OH-group, to a transition metal complex comprising the tetradentate ligand of formula I and to a process for preparing said transition metal complex. ##STR00001##

The present invention relates to the use of a transition metal catalyst TMC1, which comprises a transition metal M selected from metals of groups 7, 8, 9 and 10 of the periodic table of elements according to IUPAC and a tetradentate ligand of formula I wherein R.sup.1 are identical or different and are each an organic radical having from 1 to 40 carbon atoms, and R.sup.2 are identical or different and are each an organic radical having from 1 to 40 carbon atoms, as catalyst in processes for formation of compounds comprising at least one carboxylic acid ester functional group —O—C(═O)— starting from at least one primary alcohol and/or hydrogenation of compounds comprising at least one carboxylic acid ester functional group —O—C(═O)—. The present invention further relates to a process for hydrogenation of a compound comprising at least one carboxylic acid ester functional group —O—C(═O)—, to a process for the formation of a compound comprising at least one carboxylic acid ester functional group —O—C(═O)— by dehydrogenase coupling of at least one primary alcohol with a second alcoholic OH-group, to a transition metal complex comprising the tetradentate ligand of formula I and to a process for preparing said transition metal complex. ##STR00001##

The invention provides a process for producing diol, characterized in that the process comprises the steps of (1-i) addition of alkylene oxide and carbon dioxide to an H-functional starter substance in the presence of a catalyst to obtain polyether carbonate polyol and cyclic carbonate, (1-ii) separation of the cyclic carbonate from the resulting reaction mixture from step (1-i), (1-iii) hydrolytic cleavage of the cyclic carbonate separated from step (1-ii) into carbon dioxide and diol, (1-iv) optionally distillative purification of the diol from step (1-iii), wherein (η) to the cyclic carbonate from step (1-ii) and/or to the diol a Lewis or Brønsted acid, excluding carboxylic acids having a pKa of >3.0, and optionally water are added and the reaction mixture obtained is optionally neutralized.

The invention provides a process for producing diol, characterized in that the process comprises the steps of (1-i) addition of alkylene oxide and carbon dioxide to an H-functional starter substance in the presence of a catalyst to obtain polyether carbonate polyol and cyclic carbonate, (1-ii) separation of the cyclic carbonate from the resulting reaction mixture from step (1-i), (1-iii) hydrolytic cleavage of the cyclic carbonate separated from step (1-ii) into carbon dioxide and diol, (1-iv) optionally distillative purification of the diol from step (1-iii), wherein (η) to the cyclic carbonate from step (1-ii) and/or to the diol a Lewis or Brønsted acid, excluding carboxylic acids having a pKa of >3.0, and optionally water are added and the reaction mixture obtained is optionally neutralized.

A method for extracting polyol from a fermentation process is disclosed. The preparing method includes rectifying and purifying PDO (1,3-propanediol) from a polyol fermentation broth after concentration to form a steam condensate, wherein the concentration is a evaporative dehydration; and filtering the steam condensate through a reverse osmosis membrane to form a concentrated solution, wherein the retentate of the reverse osmosis flows back to the evaporative dehydration, and the penetrant of the reverse osmosis can be reused as a fermentation ingredient, as cleaning water or for sewage treatment; and the water content of the concentrated solution after the evaporative dehydration is 5-25 wt %; and the yield of PDO is 99.5%. The preparing method meets the requirements of water resources recycling, reduces the production loss of PDO and BDO (2,3-butanediol) during the concentration, and greatly cuts down on the amount of wastewater.