Process to conduct endothermic direct pyrolysis of methane in a fluidized bed reactor

Patent metadata

Field	Value
Publication number	US-12049435-B2
Application number	US-202118017360-A
Country	US
Kind code	B2
Filing date	Jul 27, 2021
Priority date	Jul 28, 2020
Publication date	Jul 30, 2024
Grant date	Jul 30, 2024

Abstract

The disclosure relates to a process to perform an endothermic methane pyrolysis reaction, said process comprising the steps of providing at least one fluidized bed reactor comprising at least two electrodes; and a bed comprising particles, wherein the particles are put in a fluidized state by passing upwardly through the said bed a fluid stream, to obtain a fluidized bed; heating the fluidized bed to a temperature ranging from 500° C. to 1200° C. to conduct the endothermic methane pyrolysis reaction; wherein the particles of the bed comprise electrically conductive particles and particles of a catalytic composition; wherein at least 10 wt. % of the particles are electrically conductive particles and have a resistivity ranging from 0.001 Ohm·cm to 500 Ohm·cm at 800° C. and wherein the step of heating the fluidized bed is performed by passing an electric current through the fluidized bed.

First claim

The invention claimed is:

1. A process to perform an endothermic methane pyrolysis reaction, said process comprising the steps of:
a) providing at least one fluidized bed reactor comprising at least two electrodes, a bed comprising particles, and optionally a solid discharge system;
b) putting the particles of the bed in a fluidized state by passing upwardly through the said bed a fluid stream, to obtain a fluidized bed;
c) heating the fluidized bed to a temperature ranging from 500° C. to 1200° C. to conduct the endothermic methane pyrolysis reaction to produce a reactor effluent comprising at least solid carbon, one or more hydrocarbons having at least two carbons and hydrogen;
d) optionally recovering from the reactor effluent produced at step (c) the one or more hydrocarbons having at least two carbons and hydrogen;

characterized in that the particles of the bed comprise electrically conductive particles and particles of a catalytic composition, wherein at least 10 wt. % of the particles based on the total weight of the particles of the bed are electrically conductive particles and have a resistivity ranging from 0.001 Ohm·cm to 500 Ohm·cm at 800° C., wherein the catalytic composition comprises a catalytic support and one or more metallic compounds selected from the group consisting of Ca, Mg, Ba, Y, La, Sc, Ce, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ru, Co, Rh, Ir, Ni, Pd, Cu, Ag, Au, Zn, Al, Ga, Si, Ge, In, Sn, Pb, and Bi;
in that from 50 wt. % to 100 wt. % of the electrically conductive particles of the bed are or comprise one or more selected from the group consisting of one or more metallic alloys, one or more non-metallic resistors, one or more metallic carbides, one or more transition metal nitrides, one or more metallic phosphides, graphite, carbon black, and any mixture thereof;
in that the void fraction of the bed is ranging from 0.5 to 0.8;
and in that the step (c) of heating the fluidized bed is performed by passing an electric current through the fluidized bed.

2. The process according to claim 1 , characterized in that the electrically conductive particles of the bed are or comprise one or more non-metallic resistors selected from the group consisting of silicon carbide, molybdenum disilicide and a mixture thereof.

3. The process according to any claim 1 , characterized in that the electrically conductive particles of the bed are or comprise a mixture of a non-metallic resistor being silicon carbide and electrically conductive particles different from silicon carbide that are graphite, characterized in that the electrically conductive particles of the bed comprise from 10 wt. % to 99 wt. % of silicon carbide based on the total weight of the electrically conductive particles of the bed.

4. The process according to claim 1 , characterized in that, wherein the at least one fluidized bed reactor provided in step a) comprises a heating zone and a reaction zone and wherein the fluid stream provided in step b) is provided to the heating zone and comprises diluent gases, the step c) of heating the fluidized bed to a temperature ranging from 500° C. to 1200° C. to conduct the endothermic methane pyrolysis reaction comprises the following sub-steps:
heating the fluidized bed to a temperature ranging from 500° C. to 1200° C. by passing an electric current through the heating zone of the at least one fluidized bed,
transporting the heated particles from the heating zone to the reaction zone,
in the reaction zone, putting the heated particles in a fluidized state by passing upwardly through the said bed of the reaction zone a fluid stream comprising a methane feedstock and optional diluent gases to obtain a fluidized bed and to conduct the endothermic methane pyrolysis reaction on the methane feedstock, and
recovering the particles from the reaction zone and recycling them to the heating zone.

5. The process according to claim 1 , characterized in that the electrically conductive particles of the bed comprise one or more metallic alloys selected from the group consisting of Ni-Cr, Fe-Ni—Cr, Fe-Ni—Al and a mixture thereof.

6. The process according to claim 1 , characterized in that the one or more metallic compounds of the catalytic composition are selected from Fe, Mo, W or Re.

7. The process according to claim 1 , characterized in that the one or more metallic compounds of the catalytic composition are selected from the group consisting of an elemental, a metal oxide, carbide, sulphide, nitride, and phosphide form.

8. The process according to claim 1 , characterized in that the one or more metallic compounds of the catalytic composition are deposited on the catalyst support in an amount ranging from 0.1 wt. % to 20.0 wt. % based on the total weight of said catalyst composition, characterized in that said catalytic support is selected from the group consisting of carbon materials, one or more zeolites selected from the group consisting of AEL, AFI, AFO, BEA, CHA, ERI, FAU, FER, ITE, ITH, IWR, IWS, IWW, KFI, LEV, LTL, MEL, MFI, MFS, MOR, MSE, MTT, MTW, MWW, TON and VFI families, Al 2 O 3 , and one or more mesoporous materials and is present in an amount of at least 60 wt. % based on the total molar content of the catalyst composition; characterized in that when said catalytic support is said one or more zeolites, said one or more zeolites are subjected to a step of steaming before step (c).

9. The process according to claim 8 , characterized in that said catalytic support is one or more zeolites, and said one or more zeolites comprise a molar ratio of silicon over the sum of the amount of the aluminium and the metallic element of at least 5.

10. The process according to claim 8 , characterized in that said catalytic support is one or more zeolites; and said one or more zeolites are selected from the MFI family, or that said one or more zeolites have a crystalline alumino-silicate oxide framework substituted with a metal selected from the group consisting of Fe, Sn, Hf, Zn, Zr, Ti, V, Ta, Ga, Ge, Nb, Mn, Mo, W, Co, and Cd.

11. The process according to claim 1 , characterized in that the content of the particles of the catalytic composition based on the total weight of the particle of the bed ranges from 10 wt. % to 100 wt. %.

Assignees

• Totalenergies Onetech

Inventors

• Veryasov Gleb
• Nesterenko Nikolai
• Vermeiren Walter

Classifications

• C01B2203/1241

  Natural gas or methane · CPC title

• C01B2203/0277

  containing a catalytic decomposition step · CPC title

• B01J2208/0053

  Controlling multiple zones along the direction of flow, e.g. pre-heating and after-cooling · CPC title

• B01J2208/00415

  electric resistance heaters · CPC title

• B01J2208/00398

  inside the reactor bed · CPC title