Induction-heated reactors for gas phase catalyzed reactions

• US 20030175196A1
• Filed: 03/14/2002
• Published: 09/18/2003
• Est. Priority Date: 03/14/2002
• Status: Active Grant

• Current Assignee: Invista North America Sarl (Invista)
• Original Assignee: Invista North America Sarl (Invista)
• Inventors: Sengupta, Sourav K., Mehdizadeh, Mehrdad, Pereira, Carmo Joseph, Blackwell, Benny E., Kirby, Gregory S., Fallon, Cynthia K., Koch, Theodore Augur
• Granted Patent: US 7,070,743 B2
• Time in Patent Office: Days
• US Class Current: 423/376
• CPC Class Codes: B01J 12/007 in the presence of catalytically active bodies, e.g. porous plates
• CPC Class Codes: B01J 19/0013 Controlling the temperature of the process
• CPC Class Codes: B01J 19/087 employing electric or magnetic energy
• CPC Class Codes: B01J 19/2485 Monolithic reactors
• CPC Class Codes: B01J 19/2495 Net-type reactors
• CPC Class Codes: B01J 2219/0803 employing electric or magnetic energy
• CPC Class Codes: B01J 2219/0854 employing electromagnets
• CPC Class Codes: B01J 2219/0862 employing multiple (electro)magnets
• CPC Class Codes: B01J 2219/0871 Heating or cooling of the reactor
• CPC Class Codes: B01J 2219/0883 Gas-gas
• CPC Class Codes: B01J 2219/0892 involving catalytically active material
• CPC Class Codes: B01J 35/04 Foraminous structures, sieves, grids, honeycombs
• CPC Class Codes: B01J 35/56 Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
• CPC Class Codes: B29B 7/002 Methods chemical aspects C08J3/00
• CPC Class Codes: B29B 7/826 Apparatus therefor
• CPC Class Codes: C01C 3/0233 making use of fluidised beds, e.g. the Shawinigan-process
• CPC Class Codes: F01N 2900/1602 Temperature of exhaust gas apparatus
• CPC Class Codes: H05B 6/108 for heating a fluid

Abstract

Elevated temperature, gas-phase, catalyzed processes for preparing HCN in which induction heating is used as a source of energy, and novel apparatus for carrying out said processes.

Claims

1. An apparatus for conducting elevated temperature, gas phase, catalyzed chemical reaction for the preparation of HCN comprising:

a reaction chamber comprised of a substantially gas-impermeable electrically non-conductive material,

a hollow cylindrically shaped electrically conductive and gas-permeable catalyst/susceptor having a substantially annular-shaped cross-section, said catalyst/susceptor being positioned within said reaction chamber and surrounding an electrically non-conductive cylinder,

said catalyst/susceptor being surrounded by an induction coil energizable by a power source capable of supplying alternating current,

said catalyst/susceptor being inductively heatable by an alternating magnetic field produced by said induction coil to a temperature sufficient to effect the chemical reaction.

2. The apparatus of claim 1 wherein said electrically non-conductive cylinder is substantially gas-impermeable, thereby enabling said gases to flow axially through said catalyst/susceptor.

3. The apparatus of claim 1 wherein said electrically non-conductive cylinder is substantially gas-permeable, thereby enabling said gases to flow radially through said catalyst/susceptor.

4. The apparatus of claim 1 wherein said induction coil has uniform spacing throughout its length.

5. The apparatus of claim 1 wherein the energy deposition intensity of said induction coil varies along the length of said cylindrical catalyst/susceptor.

6. The apparatus of claim 5 wherein said induction coil is comprised of two or more sections in which each of said sections carries a current of different magnitude from that of each of the other one or more sections.

7. The apparatus of claim 5 wherein said induction coil is comprised of two or more sections in which the coil spacing in one of said sections differs from the coil spacing in each of the other one or more sections.

8. The apparatus of claim 1 wherein said catalyst/susceptor is comprised of multiple continuous wraps of gauze.

9. The apparatus of claim 1 wherein said catalyst/susceptor is comprised of catalytic metal foam.

10. The apparatus of claim 1 wherein said catalyst/susceptor is comprised of a plurality of annular-shaped rings of gauze stacked upon one another.

11. The apparatus of claim 1 wherein said catalyst/susceptor is comprised of concentric annular layers having different bulk electrical conductivities.

12. The apparatus of claim 1 wherein said catalyst/susceptor is comprised of one or more platinum group metals.

13. The apparatus of claim 1 wherein said catalyst/susceptor has an outside diameter that is 0.1 to 0.9 that of the inside diameter of said induction coil.

14. A process for the preparation of HCN which comprises passing ammonia and a gaseous hydrocarbon having 1 to 6 carbon atoms through a catalyst structure comprising a substantially cylindrical electrically conductive and gas-permeable catalytic platinum group metal catalyst/susceptor, said catalyst/susceptor being hollow and surrounding an electrically non-conductive cylinder, said catalyst/susceptor having continuous electrical conduction paths around its circumference in the plane normal to the axis of said circumference, and being heated by an induction heating coil at a frequency between 50 Hz to 30 MHz to a temperature sufficient to effect reaction of said reactants, said cylindrical catalyst/susceptor having sufficient bulk electrical resistivity to have sufficient induction heating efficiency to promote catalytic activity.

15. The process of claim 14 wherein said ammonia and said hydrocarbon are made to flow axially through said catalyst/susceptor.

16. The process of claim 14 wherein said ammonia and said hydrocarbon are made to flow radially through said catalyst/susceptor.

17. The process of claim 14 wherein said induction coil has uniform spacing throughout its length.

18. The process of claim 14 wherein the energy deposition intensity of said induction coil varies along the length of said cylindrical catalyst/susceptor.

19. The process of claim 18 wherein said induction coil is comprised of two or more sections in which each of said sections carries a current of different magnitude from that of each of the other one or more sections.

20. The process of claim 18 wherein said induction coil is comprised of two or more sections in which the coil spacing in one of said sections differs from the coil spacing in each of the other one or more sections.

21. The process of claim 14 wherein said catalyst/susceptor is comprised of multiple continuous wraps of gauze.

22. The process of claim 14 wherein said catalyst/susceptor is comprised of catalytic metal foam.

23. The process of claim 14 wherein said catalyst/susceptor is comprised of a plurality of annular-shaped rings of gauze stacked upon one another.

24. The process of claim 14 wherein said catalyst/susceptor is comprised of concentric annular layers having different bulk electrical conductivities.

25. The process of claim 14 wherein said catalyst/susceptor is comprised of one or more platinum group metals.

26. The process of claim 14 wherein said catalyst/susceptor has an outside diameter that is 0.1 to 0.9 that of the inside diameter of said induction coil.

27. The process of claim 14 wherein said hydrocarbon comprises methane.