Carbonate ester purification method, carbonate ester solution production method, and carbonate ester purification apparatus

Patent metadata

Field	Value
Publication number	US-10351507-B2
Application number	US-201515538621-A
Country	US
Kind code	B2
Filing date	Dec 25, 2015
Priority date	Dec 26, 2014
Publication date	Jul 16, 2019
Grant date	Jul 16, 2019

Abstract

A carbonate ester purification apparatus including a first distillation column in which an alcohol and a first solution containing a carbonate ester and formaldehyde, or a first solution containing a carbonate ester, formaldehyde and an alcohol is supplied to obtain a distillate containing the formaldehyde and the alcohol from a column top part while obtaining a carbonate ester solution with a lower content of formaldehyde than in the first solution from a column bottom part, a reactor having a catalyst for producing an acetal and/or a hemiacetal by reacting the formaldehyde to the alcohol and a reflux part refluxing a fluid containing the acetal and/or the hemiacetal to the first distillation column.

First claim

The invention claimed is:

1. A carbonate ester solution production method comprising:
a first distillation step of supplying an alcohol and a first solution containing a carbonate ester and formaldehyde, or supplying a first solution containing a carbonate ester, formaldehyde and an alcohol to a distillation column to obtain a distillate containing the formaldehyde and the alcohol from a column top part and to introduce the distillate to a reflux part including a reactor having a catalyst while obtaining a carbonate ester solution with a lower content of formaldehyde than in the first solution from a column bottom part; and
a reaction step of refluxing a part of a reaction product containing an acetal and/or a hemiacetal obtained by contacting the distillate with the catalyst to the distillation column while discharging a remaining part of the reaction product from the reflux part.

2. The carbonate ester solution production method according to claim 1 , comprising an alkali treatment step of mixing the first solution and an alkali to reduce an acidic substance contained in the first solution before the first distillation step.

3. The carbonate ester solution production method according to claim 1 , comprising a second distillation step of fractionating the carbonate ester solution to remove an impurity from the carbonate ester solution, the impurity being different in boiling point from the carbonate ester.

4. The carbonate ester solution production method according to claim 2 , comprising: a second distillation step of fractionating the carbonate ester solution to remove an impurity from the carbonate ester solution, the impurity being different in boiling point from the carbonate ester.

5. A carbonate ester purification apparatus comprising:
a first distillation column in which an alcohol and a first solution containing a carbonate ester and formaldehyde, or a first solution containing a carbonate ester, formaldehyde and an alcohol is supplied to obtain a distillate containing the formaldehyde and the alcohol from a column top part of the first distillation column while obtaining a carbonate ester solution with a lower content of formaldehyde than in the first solution from a column bottom part of the first distillation column;
a first reflux part including a reactor having a catalyst for producing an acetal and/or a hemiacetal by reacting the formaldehyde to the alcohol, and being configured to reflux a part of a reaction product containing the acetal and/or the hemiacetal to the distillation column while discharging a remaining part of the reaction product from the first reflux part;
a treatment tank for alkali treating the first solution by mixing the first solution and an alkali, as a pretreatment part adapted for producing the first solution prior to supplying it to the first distillation column;
a separator for removing a solid product produced by the alkali treatment, the separator being a filter;
a second distillation column adapted for receiving a second solution discharged from the column bottom part of the first distillation column, and having a pipe connected to a column bottom part thereof and a pipe connected to the column at a location between a center part and the column top part thereof to extract the carbonate ester by a side cut; and
a second reflux part connected to the column top part of the second distillation column.

6. The carbonate ester purification apparatus according to claim 5 , wherein the second distillation column is configured for fractionating the carbonate ester solution to remove an impurity from the carbonate ester solution, the impurity being different in boiling point from the carbonate ester.

7. The carbonate ester purification apparatus according to claim 5 , additionally comprising a pipe connecting the reflux part of the second distillation column and the treatment tank, wherein the pipe allows condensate condensed in the reflux part to flow through the pipe into the treatment tank.

Assignees

• Ube Industries

Inventors

• Ii Hirofumi
• FUKUI Yuya
• SHIMASAKI Yohei
• Okano Koji
• Takebayashi Koji
• Nakao Naoto

Classifications

• C07C68/08 Primary

  Purification; Separation; Stabilisation · CPC title

• B01D3/143

  by two or more of a fractionation, separation or rectification step · CPC title

• B01D3/009

  in combination with chemical reactions · CPC title

• C07C69/96

  Esters of carbonic or haloformic acids · CPC title

• B01D3/42

  Regulation; Control · CPC title