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.

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.

Embodiments of the present invention are directed to processes for the production of (R)-3-hydroxybutyl (R)-3-hydroxybyrate. Poly (R)-3-hydroxybyrate is transesterified with an alcohol, to form a first ester portion and a second ester portion. The first ester portion is reduced to the diol to form a diol portion and the diol portion is reacted with the second ester portion to produce (R)-3-hydroxybutyl (R)-3-hydroxybyrate.

Embodiments of the present invention are directed to processes for the production of (R)-3-hydroxybutyl (R)-3-hydroxybyrate. Poly (R)-3-hydroxybyrate is transesterified with an alcohol, to form a first ester portion and a second ester portion. The first ester portion is reduced to the diol to form a diol portion and the diol portion is reacted with the second ester portion to produce (R)-3-hydroxybutyl (R)-3-hydroxybyrate.

Provided is a method capable of manufacturing 1,3-butylene glycol having a high potassium permanganate test value. A method for manufacturing 1,3-butylene glycol, which is a method for obtaining purified 1,3-butylene glycol from a crude reaction liquid containing 1,3-butylene glycol, the method including: a dehydration step of removing water by distillation; a high boiling substance removal step of removing a high boiling point component by distillation; and a product distillation step of obtaining purified 1,3-butylene glycol, wherein in the product distillation step, a product column is used in which a liquid feed having a 1,3-butylene glycol concentration of 97% or higher, an acetaldehyde content of 500 ppm or lower, and a crotonaldehyde content of 200 ppm or lower is distilled under a condition of a reflux ratio of higher than 0.1, and a liquid concentrated with acetaldehyde and crotonaldehyde is distilled off from above a feed plate, and 1,3-butylene glycol is extracted from below the feed plate.

Provided is a method capable of manufacturing 1,3-butylene glycol having a high potassium permanganate test value. A method for manufacturing 1,3-butylene glycol, which is a method for obtaining purified 1,3-butylene glycol from a crude reaction liquid containing 1,3-butylene glycol, the method including: a dehydration step of removing water by distillation; a high boiling substance removal step of removing a high boiling point component by distillation; and a product distillation step of obtaining purified 1,3-butylene glycol, wherein in the product distillation step, a product column is used in which a liquid feed having a 1,3-butylene glycol concentration of 97% or higher, an acetaldehyde content of 500 ppm or lower, and a crotonaldehyde content of 200 ppm or lower is distilled under a condition of a reflux ratio of higher than 0.1, and a liquid concentrated with acetaldehyde and crotonaldehyde is distilled off from above a feed plate, and 1,3-butylene glycol is extracted from below the feed plate.

A high-purity 1,3-butylene glycol product is provided, which is colorless and odorless (or almost colorless and odorless), unlikely to cause coloration and odor over time, and, besides, unlikely to cause an acid concentration increase over time also in a state containing water. A 1,3-butylene glycol product in which at least one of a content of methyl vinyl ketone, a content of acetone, a content of butylaldehyde, a content of acetaldol, a content of a compound represented by Formula (1) below, a content of a compound represented by Formula (2) below, a content of a compound represented by Formula (3) below, and a total content of a compound represented by Formula (4) below and a compound represented by Formula (5) below, is less than 8 ppm.

A high-purity 1,3-butylene glycol product is provided, which is colorless and odorless (or almost colorless and odorless), unlikely to cause coloration and odor over time, and, besides, unlikely to cause an acid concentration increase over time also in a state containing water. A 1,3-butylene glycol product in which at least one of a content of methyl vinyl ketone, a content of acetone, a content of butylaldehyde, a content of acetaldol, a content of a compound represented by Formula (1) below, a content of a compound represented by Formula (2) below, a content of a compound represented by Formula (3) below, and a total content of a compound represented by Formula (4) below and a compound represented by Formula (5) below, is less than 8 ppm.

Provided is a method capable of manufacturing high-purity 1,3-butylene glycol having a high potassium permanganate test value, a very low content of low boiling point components, and a high initial boiling point with a high recovery rate.

The method for manufacturing 1,3-butylene is a method for obtaining purified 1,3-butylene glycol from a crude reaction liquid containing 1,3-butylene glycol. In a dehydration column used in a dehydration step, a liquid feed containing 1,3 butylene glycol and water with an acetaldehyde content of 1000 ppm or lower and a crotonaldehyde content of 400 ppm or lower is distilled under a condition of a reflux ratio of higher than 0.3, and a liquid concentrated with a low boiling point component containing water is distilled off from above a feed tray. In a product column used in a product distillation step, a liquid feed containing 1,3-butylene glycol with an acetaldehyde content of 500 ppm or lower and a crotonaldehyde content of 200 ppm or lower is distilled under a condition of a reflux ratio of higher than 0.1.

Provided is a method capable of manufacturing high-purity 1,3-butylene glycol having a high potassium permanganate test value, a very low content of low boiling point components, and a high initial boiling point with a high recovery rate.

The method for manufacturing 1,3-butylene is a method for obtaining purified 1,3-butylene glycol from a crude reaction liquid containing 1,3-butylene glycol. In a dehydration column used in a dehydration step, a liquid feed containing 1,3 butylene glycol and water with an acetaldehyde content of 1000 ppm or lower and a crotonaldehyde content of 400 ppm or lower is distilled under a condition of a reflux ratio of higher than 0.3, and a liquid concentrated with a low boiling point component containing water is distilled off from above a feed tray. In a product column used in a product distillation step, a liquid feed containing 1,3-butylene glycol with an acetaldehyde content of 500 ppm or lower and a crotonaldehyde content of 200 ppm or lower is distilled under a condition of a reflux ratio of higher than 0.1.