Fired tube conversion system and process

Patent metadata

Field	Value
Publication number	US-9914678-B2
Application number	US-201615288424-A
Country	US
Kind code	B2
Filing date	Oct 7, 2016
Priority date	Nov 4, 2015
Publication date	Mar 13, 2018
Grant date	Mar 13, 2018

Abstract

Disclosed is a process and system to convert acyclic C 5 feedstock to non-aromatic, cyclic C 5 hydrocarbon. A furnace and reactor tubes comprising a catalyst compound are disclosed. A process involving contacting acyclic C 5 feedstock with catalyst composition and obtaining cyclic C 5 hydrocarbon is also disclosed.

First claim

What is claimed is:

1. A process for converting acyclic C5 hydrocarbon to cyclic C5 hydrocarbon comprising:
a) providing a furnace comprising parallel reactor tube(s), the reactor tubes containing catalyst composition, wherein the catalyst composition comprises platinum on ZSM-5, platinum on zeolite L, and/or platinum on silicate modified silica;
b) providing a feedstock comprising acyclic C5 hydrocarbon;
c) contacting the feedstock with the catalyst composition;
d) obtaining a reactor effluent comprising cyclic C5 hydrocarbon, wherein the cyclic C5 hydrocarbon comprises cyclopentadiene;
e) discontinuing providing said feedstock comprising acyclic C5 hydrocarbons;
f) providing a rejuvenation gas comprising H 2 ;
g) contacting the rejuvenation gas with the catalyst composition to remove at least a portion of coke material on the catalyst composition; and
h) discontinuing providing a rejuvenation gas and resuming providing said feedstock comprising acyclic C5 hydrocarbons.

2. The process of claim 1 , wherein i) the reactor tubes are positioned vertically so the feedstock is provided from the top and the reactor effluent exits from the bottom and ii) the furnace comprises at least one burner positioned near the top of the reactor tubes having a flame burning in a downward direction providing heat flux near the top that is greater than heat flux near the bottom of the reactor tubes.

3. The process of claim 2 , wherein a shield blocks at least a portion of the burner flame's radiation from a bottom portion of the reactor tube.

4. The process of claim 3 , wherein the shield is a flue gas duct.

5. The process of claim 1 , wherein the reactor tubes have an inverse temperature profile or an isothermal temperature profile.

6. The process of claim 1 , wherein the contacting feedstock and catalyst composition is performed in the presence of a gas comprising H 2 and/or C 1 through C 4 hydrocarbons.

7. The process of claim 1 , further comprising promoting heat transfer from the tube wall to the catalyst composition by providing fins or contours on the inside or outside of the reactor tubes.

8. The process of claim 1 , further comprising mixing feedstock and converted cyclic C 5 hydrocarbon in the radial direction by providing mixing internals within the reactor tubes, wherein the mixing internals are positioned i) within a bed of the catalyst composition or ii) in portions of the reactor tube separating two or more zones of catalyst composition.

9. The process of claim 1 , wherein contacting step c) occurs at a temperature of about 450° C. to about 800° C.

10. The process of claim 1 , wherein the feedstock provided to the inlet of the reactor tubes has a temperature of about 450° C. to about 550° C.

11. The process of claim 1 , wherein the reactor tubes have an outlet pressure of about 4 psia to about 50 psia during contacting step c).

12. The process of claim 1 , wherein the reactor tubes, during contacting feedstock with catalyst composition, have a pressure drop measured from reactor inlet to reactor outlet from about 1 psi to about 100 psi.

13. The process of claim 1 , wherein at least about 30 wt % of the acyclic C 5 hydrocarbons is converted to cyclopentadiene.

14. The process of claim 1 , wherein the catalyst composition is an extrudate having a diameter of 2 mm to 20 mm.

15. The process of claim 1 , wherein the catalyst composition cross section is shaped with one or more lobes and/or concave sections, and wherein the catalyst composition lobes and/or concave sections are spiraled or straight.

16. The process of claim 1 , wherein the inside diameter of the reactor tubes is from about 20 mm to about 200 mm.

17. The process of claim 1 , further comprising transferring heat by convection from flue gas to rejuvenation gas, regeneration gas, steam, and/or the feedstock in a convection section of the furnace.

18. The process of claim 1 , further comprising i) providing two or more furnaces, each furnace comprising parallel reactor tube(s), the reactor tubes containing catalyst composition and ii) providing a rejuvenation gas or a regeneration gas to one or more furnaces and, at the same time, providing feedstock comprising acyclic C 5 hydrocarbons to a different one or more furnaces.

19. The process of claim 1 further comprising:
a) discontinuing providing a feedstock comprising acyclic C 5 hydrocarbons;
b) purging combustible gas, including feedstock and reactor product, from the reactor tubes to a concentration below the combustible concentration limit;
c) contacting a regeneration gas comprising an oxidizing material with the catalyst composition to oxidatively remove at least a portion of coke material on the catalyst composition;
d) purging regeneration gas from the reactor tubes to a concentration below the combustible concentration limit; and
e) discontinuing purging of regeneration gas and resuming providing a feedstock comprising acyclic C 5 hydrocarbons.

20. The process of claim 1 , wherein the catalyst composition is formed into a structured catalyst shape.

21. The process of claim 1 , further comprising providing the feedstock to at least one adiabatic reaction zone prior to the contacting of c).

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Iaccino Larry L
• Lemoine Romain O V

Classifications

• B01J2208/06

  Details of tube reactors containing solid particles · CPC title

• C07C2601/10

  the ring being unsaturated · CPC title

• B01J8/062

  being installed in a furnace · CPC title

• B01J29/44

  Noble metals · CPC title

• C07C13/15

  with a cyclopentadiene ring · CPC title