Method for producing conjugated diene

Patent metadata

Field	Value
Publication number	US-11319261-B2
Application number	US-201716098727-A
Country	US
Kind code	B2
Filing date	Apr 26, 2017
Priority date	May 6, 2016
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

Provided is a method of producing a conjugated diene, including a step of dehydrating a γ,δ-unsaturated alcohol in the presence of a solid acid catalyst having a Hammett acidity function (H0) of −12.2 or less.

First claim

The invention claimed is:

1. A method of producing a conjugated diene, comprising:
preparing a mixture consisting of at least one solvent and an aged solid acid catalyst;
heating the mixture to a dehydration reaction temperature;
continuously adding a γ,δ-unsaturated alcohol to the mixture at the dehydration reaction temperature;
dehydrating the γ,δ-unsaturated alcohol to obtain the conjugated diene and water; and
continuously removing the conjugated diene and the water from the mixture:
wherein
a Hammett acidity function (H 0 ) of the aged solid catalyst is −12.2 or less, a BET surface area of the aged solid catalyst is from 20 m 2 /g to 800 m 2 /g,
a total amount of the conjugated diene and water removed from the mixture is 0.8 to 1.2 times the mass of the γ,δ-unsaturated alcohol,
the at least one solvent is selected from the group consisting of aliphatic hydrocarbons and aromatic hydrocarbons, and
an amount of the at least one solvent in the mixture is from 80 to 99% by mass.

2. The method according to claim 1 , wherein the solid acid catalyst is an oxoacid-supported metal oxide.

3. The method according to claim 1 , wherein the solid acid catalyst is a sulfuric acid-supported metal oxide or a tungstic acid-supported metal oxide.

4. The method according to claim 1 , wherein the solid acid catalyst is sulfated zirconia.

5. The method according to claim 1 , wherein the γ,δ-unsaturated alcohol is 3-methyl-3-buten-1-ol.

6. The method according to claim 1 , wherein the solid acid catalyst is aged by treatment at a temperature of 100 to 300° C. prior to dehydrating the γ,δ-unsaturated alcohol.

7. The method according to claim 1 wherein the dehydrating is conducted in an inert gas atmosphere.

8. The method according to claim 1 , wherein the at least one solvent is selected from the group consisting of octane, nonane, decane, kerosene and liquid paraffins.

Assignees

• Kuraray Co

Inventors

• Suzuki Takahiro
• Senda Kosuke
• Suzuki Yutaka

Classifications

• C07C2521/06

  Silicon, titanium, zirconium or hafnium; Oxides or hydroxides thereof · CPC title

• B01J37/0201

  Impregnation · CPC title

• C07C1/24 Primary

  by elimination of water · CPC title

• C07B61/00

  Other general methods · CPC title

• C07C11/18

  Isoprene · CPC title