Catalytic hydrodearylation of heavy aromatic streams containing dissolved hydrogen with fractionation

Patent metadata

Field	Value
Publication number	US-11267769-B2
Application number	US-202117154561-A
Country	US
Kind code	B2
Filing date	Jan 21, 2021
Priority date	Oct 7, 2019
Publication date	Mar 8, 2022
Grant date	Mar 8, 2022

Abstract

Systems and methods for hydrodearylation of a hydrocarbon feed stream comprising non-condensed alkyl-bridged multi-aromatic hydrocarbons, the method including supplying a hydrogen feed to the hydrocarbon feed stream comprising non-condensed alkyl-bridged multi-aromatic hydrocarbons; mixing the hydrogen feed with the hydrocarbon feed stream to saturate the hydrocarbon feed stream with hydrogen gas to create a hydrogen-enriched liquid hydrocarbon stream; passing the hydrogen-enriched liquid hydrocarbon stream to a hydrodearylation reactor without a separate gaseous phase of hydrogen; allowing the hydrogen-enriched liquid hydrocarbon stream to react in presence of a catalyst under specific reaction conditions to produce a product stream comprising a reduced concentration of di-aromatic compounds and an increased concentration of mono-aromatic compounds compared to the hydrocarbon feed stream comprising non-condensed alkyl-bridged multi-aromatic hydrocarbons; and recovering, from the hydrodearylation reactor, a product stream for a downstream process, wherein the non-condensed alkyl-bridged multi-aromatic hydrocarbons include at least two benzene rings connected by an alkyl bridge group having at least two carbons, wherein the benzene rings are connected to different carbons of the alkyl bridge group.

First claim

What is claimed is:

1. A method for hydrodearylation of a hydrocarbon feed stream comprising non-condensed alkyl-bridged multi-aromatic hydrocarbons, the method comprising the steps of:
supplying a hydrogen feed stream to the hydrocarbon feed stream comprising non-condensed alkyl-bridged multi-aromatic hydrocarbons;
mixing the hydrogen feed stream with the hydrocarbon feed stream to saturate the hydrocarbon feed stream with hydrogen gas to create a hydrogen-enriched liquid hydrocarbon stream;
passing the hydrogen-enriched liquid hydrocarbon stream to a hydrodearylation reactor without a separate gaseous phase of hydrogen; and
allowing the hydrogen-enriched liquid hydrocarbon stream to react in presence of a catalyst under specific reaction conditions as a liquid, in a two phase reactor without a separate hydrogen gas phase outside of hydrogen dissolved in the hydrogen-enriched liquid, to produce a product stream comprising a reduced concentration of di-aromatic compounds and an increaced concentration of mono-aromatic compounds compared to the hydrocarbon feed stream comprising non-condensed alkyl-bridged multi-aromatic hydrocarbons;
where the non-condensed alkyl-bridged multi-aromatic hydrocarbons include at least two benzene rings connected by an alkyl bridge group having at least two carbons, where the benzene rings are connected to different carbons of the alkyl bridge group.

2. The method of claim 1 , further comprising the step of recovering, from the hydrodearylation reactor, the product stream for a downstream process.

3. The method of claim 1 , where the hydrocarbon feed stream comprises C 9+ compounds obtained from a xylene rerun column.

4. The method of claim 1 , where the hydrocarbon feed stream comprises C 11+ compounds obtained from a xylene rerun column.

5. The method of claim 1 , where the hydrocarbon feed stream comprises hydrocarbon compounds with a boiling point of about 180° C. and greater.

6. The method of claim 1 , where the hydrogen feed stream includes a recycled hydrogen stream and a makeup hydrogen stream.

7. The method of claim 1 , where the hydrogen feed stream comprises at least 70% hydrogen by weight.

8. The method of claim 1 , where the catalyst is presented as a catalyst bed in the hydrodearylation reactor.

9. The method of claim 8 , where the catalyst bed includes two or more catalyst beds.

10. The method of claim 1 , where the catalyst includes a support being at least one member of the group consisting of silica, alumina, and combinations thereof, and further includes an acidic component being at least one member of the group consisting of amorphous silica-alumina, zeolite, and combinations thereof.

11. The method of claim 10 , where the catalyst includes an IUPAC Group 8-10 metal being at least one member of the group consisting of iron, cobalt, and nickel, and combinations thereof and further includes an IUPAC Group 6 metal being at least one member of the group consisting of molybdenum and tungsten, and combinations thereof.

12. The method of claim 11 , where the IUPAC 8-10 metal is 2 to 20 percent by weight of the catalyst and the IUPAC Group 6 metal is 1 to 25 percent by weight of the catalyst.

13. The method of claim 1 , where the catalyst includes at least one of nickel, molybdenum, ultrastable Y-type zeolite, and γ-alumina support.

14. The method of claim 1 , where the catalyst includes a noble IUPAC Group 8-10 metal.

15. The method of claim 1 , where the catalyst includes a binder selected from the group consisting of: alumina, silica, titania, silica-alumina, alumina-titania, alumina-zirconia, alumina-boria, phosphorus-alumina, silica-alumina-boria, phosphorus-alumina-boria, phosphorus-alumina-silica, silica-alumina-titania, and silica-alumina-zirconia.

16. The method of claim 1 , where specific reaction conditions include an operating temperature of the hydrodearylation reactor being in the range of about 200° C. to about 450° C.

17. The method of claim 16 , where the operating temperature of the hydrodearylation reactor is about 300° C.

18. The method of claim 16 , where the operating temperature of the reactor is about 350° C.

19. The method of claim 1 , where the mixing step comprises a first mixing step and a second mixing step, where the first mixing step mixes a first hydrocarbon recycle stream with the hydrocarbon feed stream, and where the second mixing step mixes a second hydrocarbon recycle stream with the hydrocarbon feed stream.

20. The method of claim 19 , where the step of supplying a hydrogen feed stream comprises a first step of supplying a hydrogen feed stream and a second step of supplying a hydrogen feed stream, the first step of supplying a hydrogen feed stream occurring before the first mixing step, and the second step of supplying a hydrogen feed stream occurring before the second mixing step.

21. The method of claim 19 , where the first mixing step uses a static mixer to mix hydrogen, the hydrocarbon feed stream, and the first hydrocarbon recycle stream, and where the second mixing step uses a static mixer to mix hydrogen, the hydrocarbon feed stream, and the second hydrocarbon recycle stream.

22. The method of claim 1 , further comprising the step of flowing the product stream to a separation zone with a hot separator to separate the product stream into a hydrodearylated gas tops stream and a hydrodearylated liquid bottoms stream, where a portion of the hydrodearylated liquid bottoms stream is recycled for mixing with the hydrogen feed stream and the hydrocarbon feed stream in the mixing step.

23. The method of claim 22 , further comprising the steps of flowing the hydrodearylated gas tops stream and a remaining portion of the hydrodearylated liquid bottoms stream to a stripper column of a fractionation zone, producing a light vapor stripper top stream and a heavy stripper column bottom stream, flowing the heavy stripper column bottom stream to a splitter column, producing a light splitter column top stream and a heavy splitter column bottom stream, and recycling at least a portion of the heavy splitter column bottom stream for mixing with the hydrogen feed stream and the hydrocarbon feed stream in the mixing step.

24. The method of claim 1 , further comprising the step of flashing excess hydrogen gas from the hydrogen-enriched liquid hydrocarbon stream before the step of passing.

25. The method of claim 1 , where a molar ratio of hydrogen from the hydrogen feed stream to hydrocarbons in the hydrocarbon feed stream is between about 0.1:1 to about 0.9:1.

26. The method of claim 1 , where a molar ratio of hydrogen from the hydrogen feed stream to hydrocarbons in the hydrocarbon feed is between about 0.3:1 to about 0.7:1.

27. The method of claim 1 , where the weight percent of mono-aromatics in the product stream increases by between about 0.5% to about 25% compared to the weight percent of mono-aromatics in the hydrocarbon feed stream and where the weight percent of di-aromatics in the product stream decreases by between about 5% to about 75% compared to the weight percent of di-aromatics in the hydrocarbon feed stream.

28. The method of claim 1 , further comprising the step of recycling a first fractionation stream to the mixing step after fractionation of a portion of the product stream into the first fractionation stream comprising hydrocarbon components with a boiling point of greater than about

Assignees

• Saudi Arabian Oil Co

Inventors

• Koseoglu Omer Refa
• Hodgkins Robert Peter
• Beadle Bruce Richard
• Ramaseshan Vinod

Classifications

• B01J2208/00849

  outside the bed, e.g. baffles · CPC title

• B01J4/005

  provided with baffles · CPC title

• B01D3/346

  the gas being used for removing vapours, e.g. transport gas · CPC title

• B01J8/0492

  Feeding reactive fluids (for solid material, see B01J8/0015) · CPC title

• C10G2400/30

  Aromatics · CPC title