Title:
1,6-ヘキサンジオールの製造方法
Document Type and Number:
Japanese Patent JP2012510973
Kind Code:
A
Abstract:
A process for preparing 1,6-hexanediol from a carboxylic acid mixture which comprises adipic acid, 6-hydroxycaproic acid and small amounts of 1,4-cyclohexanediols and is obtained as a by-product of the oxidation of cyclohexane to cyclohexanone/cyclohexanol with oxygen or oxygen-comprising gases by water extraction of the reaction mixture, by esterification and hydrogenation to hexanediol, which comprises a) the mono- and dicarboxylic acids present in the aqueous reaction mixture are reacted with a low molecular weight alcohol to give the corresponding carboxylic esters, b) the resulting esterification mixture is freed of excess alcohol and low boilers in a first distillation stage, c) in a second distillation stage, a separation is performed of the bottom product into an ester fraction essentially free of 1,4-cyclohexanediols and a fraction comprising at least the majority of the 1,4-cyclohexanediols, d) the ester fraction from (c) is catalytically hydrogenated and 1,6-hexanediol is obtained in a manner known per se by distilling the hydrogenation product, e) optionally the bottom product of stage c) is subjected to a further esterification reaction with a low molecular weight alcohol, the low molecular weight alcohol is distillatively removed on completion of the esterification reaction, then adipic diesters and 6-hydroxycaproic esters are substantially separated from 1,4-cyclohexanediols and high boilers in the remaining bottom stream by distillation and said adipic diesters and 6-hydroxycaproic esters are fed to stage c), which comprises performing at least one of the esterification reactions with a catalyst which comprises at least one element of groups 3-14, and adding a monomeric or oligomeric polyol with at least 3 hydroxyl functions after the esterification reaction. After step c) of the process according to the invention, in a third distillation stage, a stream comprising essentially methyl 6-hydroxycaproate can be at least partly removed and heated to temperatures above 200° C. under reduced pressure, which cyclizes 6-hydroxycaproic ester to caprolactone, and pure ε-caprolactone can be obtained from the cyclization product by distillation.
Inventors:
Olivier Abyssal
Geat-Deter Theven
Rolf Pincos
Tobias Verpnitz
Geat-Deter Theven
Rolf Pincos
Tobias Verpnitz
Application Number:
JP2011538973A
Publication Date:
May 17, 2012
Filing Date:
November 30, 2009
Export Citation:
Assignee:
BASF SE
International Classes:
C07C29/149; C07C31/20; C07B61/00
Attorney, Agent or Firm:
Takuya Kuno
Toshio Yano
Takahashi
Kiyoshi Kuruma
Kimihiro Hoshi
Hiroyasu Ninomiya
Ryoichi Shino
Einzel Felix-Reinhard
Toshio Yano
Takahashi
Kiyoshi Kuruma
Kimihiro Hoshi
Hiroyasu Ninomiya
Ryoichi Shino
Einzel Felix-Reinhard