Method for producing 1,3-butadiene

Patent metadata

Field	Value
Publication number	US-11479518-B2
Application number	US-202017623077-A
Country	US
Kind code	B2
Filing date	Jul 6, 2020
Priority date	Jul 5, 2019
Publication date	Oct 25, 2022
Grant date	Oct 25, 2022

Abstract

The method of the present invention for producing 1,3-butadiene includes: vaporizing an ethanol feedstock in a vaporizer ( 104 ), supplying the feedstock to two or more parallel first reactors ( 108 ) to convert ethanol into acetaldehyde in the presence of a first catalyst; supplying a resulting intermediate gas to a second reactor ( 110 ) to convert ethanol and acetaldehyde into 1,3-butadiene in the presence of a second catalyst; purifying a resulting crude gas containing 1,3-butadiene by a gas-liquid separator ( 112 ), a first distillation column ( 114 ), a fourth reactor ( 116 ), and a second distillation column ( 118 ); and supplying an oxygen-containing gas to at least one of the two or more parallel first reactors ( 108 ) under specific conditions, while discharging a carbon dioxide-containing gas from the first reactor ( 108 ), to thereby regenerate the first catalyst, while continuing the conversion reaction.

First claim

The invention claimed is:

1. A method for continuously producing 1,3-butadiene from an ethanol feedstock containing ethanol, comprising:
a gas preparation step of preparing an ethanol-containing gas from the ethanol feedstock; a conversion step of converting ethanol in the ethanol-containing gas to 1,3-butadiene in the presence of a catalyst; a purification step of purifying a crude gas containing the 1,3-butadiene obtained in the conversion step to obtain a purified 1,3-butadiene, a catalyst regeneration step of regenerating the catalyst through a line different from a line used in the conversion step, and a nitrogen purging step,
wherein the gas preparation step comprises a step A1 of vaporizing the ethanol feedstock to obtain the ethanol-containing gas under a pressure of −1.0 to 1.0 MPaG and at a temperature of −100 to 200° C.,
the conversion step uses two or more parallel reactors for at least a part of a conversion reaction of converting ethanol in the ethanol-containing gas to 1,3-butadiene in the presence of the catalyst, while being accompanied by generation of hydrogen,
the purification step comprises at least one step selected from the group consisting of: a step C1 of converting butene in the crude gas into 1,3-butadiene by dehydrogenation reaction, a step C2 of separating hydrogen gas from the crude gas by gas-liquid separation to obtain a 1,3-butadiene-containing liquid, a step C3 of distilling a liquefied product of the crude gas or the 1,3-butadiene-containing liquid to separate the liquefied product or the 1,3-butadiene-containing liquid into an ethylene-containing gas, a 1,3-butadiene-containing effluent, and an acetaldehyde-containing liquid, and a step C4 of distilling the acetaldehyde-containing liquid to separate the acetaldehyde-containing liquid into an acetaldehyde-containing gas and a residual liquid containing water
the catalyst regeneration step comprises supplying an oxygen-containing gas having an oxygen concentration of 0.01 to 100% by volume to at least one reactor of the two or more parallel reactors, which is different from that or those used in the conversion step, and discharging a carbon dioxide-containing gas from the reactor, to thereby regenerate the catalyst, while continuing the conversion step, and
the nitrogen purging step comprises supplying nitrogen gas to the reactor after the conversion step, thereby replacing an atmosphere in the reactor with a nitrogen gas atmosphere.

2. The method according to claim 1 , wherein the conversion step comprises a step B1 of supplying the ethanol-containing gas obtained in the step A1 to a first reactor and converting ethanol into acetaldehyde in the presence of a first catalyst under a pressure of 0 to 1.0 MPaG and at a temperature of 50 to 500° C., and a step B2 of supplying an intermediate gas containing ethanol and acetaldehyde obtained in the step B1 to a second reactor and converting the ethanol and the acetaldehyde into 1,3-butadiene under a pressure of 0 to 1.0 MPaG and at a temperature of 50 to 500° C. in the presence of a second catalyst.

3. The method according to claim 2 , wherein the step B1 uses two or more parallel first reactors, and
the catalyst regeneration step comprises of supplying the oxygen-containing gas to at least one of the two or more parallel first reactors under a pressure of 0 to 1.0 MPaG and at a temperature of 0 to 500° C., and discharging a carbon dioxide-containing gas from the first reactor, to thereby regenerate the first catalyst.

4. The method according to claim 3 , wherein the catalyst regeneration step is performed, based on results of monitoring an ethanol/acetaldehyde molar ratio in the intermediate gas supplied to the second reactor with an analyzer.

5. The method according to claim 2 , wherein the conversion step further comprises a step B3 of mixing one or both of a part of the ethanol-containing gas obtained in the step A1 and the acetaldehyde-containing gas obtained in the step C4 with the intermediate gas, thereby adjusting an ethanol/acetaldehyde molar ratio in the intermediate gas supplied to the second reactor to 1 to 100.

6. The method according to claim 5 , wherein an amount of either one or both of the ethanol-containing gas and the acetaldehyde-containing gas which are mixed with the intermediate gas in the step B3 is adjusted, based on results of monitoring the ethanol/acetaldehyde molar ratio in the intermediate gas supplied to the second reactor with an analyzer.

7. The method according to claim 2 , wherein the conversion step further comprises a step B4 of separating hydrogen gas from the intermediate gas.

8. The method according to claim 2 , wherein the catalyst regeneration step is performed after the intermediate gas is discharged from the first reactor, based on results of monitoring a hydrogen concentration in the first reactor with an analyzer.

9. The method according to claim 2 , wherein, in the catalyst regeneration step, an amount of oxygen in the first reactor is adjusted, based on results of monitoring a hydrogen concentration in the first reactor with an analyzer.

10. The method according to claim 2 , wherein the step B2 uses two or more parallel second reactors, and
the catalyst regeneration step comprises supplying the oxygen-containing gas to at least one of the two or more parallel second reactors under a pressure of 0 to 1.0 MPaG and at a temperature of 0 to 500° C., and discharging a carbon dioxide-containing gas from the second reactor, to thereby regenerate the second catalyst, while continuing the conversion step.

11. The method according to claim 2 , wherein the catalyst regeneration step is performed after the crude gas is discharged from the second reactor, based on results of monitoring a hydrogen concentration in the second reactor with an analyzer.

12. The method according to claim 2 , wherein, in the catalyst regeneration step, an amount of oxygen in the second reactor is adjusted, based on results of monitoring a hydrogen concentration in the second reactor with an analyzer.

13. The method according to claim 2 , wherein the crude gas is discharged from the second reactor, based on results of monitoring a 1,3-butadiene concentration and a hydrogen concentration in the second reactor with an analyzer.

14. The method according to claim 1 , wherein the conversion step comprises a step B5 of supplying the ethanol-containing gas to two or more parallel third reactors and converting ethanol into 1,3-butadiene in the presence of a third catalyst under a pressure of 0 to 1.0 MPaG and at a temperature of 50 to 500° C.

15. The method according to claim 14 , wherein the catalyst regeneration step comprises supplying the oxygen-containing gas to at least one of the two or more parallel third reactors under a pressure of 0 to 1.0 MPaG and at a temperature of 0 to 500° C., and discharging a carbon dioxide-containing gas from the third reactor, to thereby regenerate the third catalyst, while continuing the conversion step.

16. The method according to claim 1 , wherein the gas preparation step further comprises a step A2 of mixing at least one type of gas with the ethanol-containing gas to adjust the concentration of ethanol in the ethanol-containing gas to fall within a range of 0.1 to 100% by volume.

Assignees

• Sekisui Chemical Co Ltd

Inventors

• YAGIHASHI Noritoshi
• NISHIYAMA Haruka
• Nakama Yuki

Classifications

• C07C7/04

  by distillation · CPC title

• C07C2521/06

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

• C07C5/333

  Catalytic processes · CPC title

• Y02P20/52

  using catalysts, e.g. selective catalysts · CPC title

• C07C1/2072

  by condensation (C07C2/86 takes precedence) · CPC title