Systems and methods for producing high purity aromatics from a mixed aromatic feed stream

Patent metadata

Field	Value
Publication number	US-12459879-B2
Application number	US-202418661278-A
Country	US
Kind code	B2
Filing date	May 10, 2024
Priority date	Oct 14, 2021
Publication date	Nov 4, 2025
Grant date	Nov 4, 2025

Abstract

The present disclosure provides systems and methods for producing aromatic compounds in high yield from a mixed aromatic feed stream. Also disclosed are systems and methods for producing aromatic compounds in high yield from oxygenated hydrocarbons such as carbohydrates, sugars, sugar alcohols, sugar degradation products, and the like.

First claim

The invention claimed is:

1 . A method for separating an aromatic compound from a mixed aromatic feed stream, the method comprising:
(i) contacting a mixed aromatic feed stream comprising C 7-10 aromatic hydrocarbons with an aromatics processing catalyst to produce a product stream comprising C 8 aromatics, wherein the aromatics processing catalyst comprises a transalkylation catalyst, a dealkylation catalyst, a hydrocracking catalyst, or a combination thereof, wherein the mixed aromatic feed stream comprises greater than 1 wt % of non-aromatic components based on the total weight of the mixed aromatic feed stream, and wherein the mixed aromatic feed stream is substantially free of (a) C 12+ aromatics and (b) co-boiling contaminants for benzene and toluene; and (ii) fractionating the product stream to separate an aromatic compound from the product stream, which comprises:
(ii-a) feeding the product stream comprising C 8 aromatics to a first distillation column that fractionates the product stream to separate a C 7− stream from a C 8+ stream; and
(ii-b) feeding at least a portion of the C 8+ stream to a third distillation column that fractionates the portion of the C 8+ stream into a C 8 stream and a C 9+ stream, wherein the C 8 stream comprises the C 8 aromatics,
(iii) subjecting at least a portion of the C 8 stream to an isomer-recovery process unit to produce a xylene isomer stream and a raffinate stream comprising non-recovered C 8 compounds, wherein at least a portion of the C 8+ stream bypasses the distillation column of (ii-b) and is combined with the C 8 stream entering the isomer-recovery process unit; and (iv) contacting the raffinate stream with an isomerization catalyst to produce an isomerization product stream, wherein the isomerization product stream comprises at least one xylene isomer, and wherein at least a portion of the isomerization product stream is combined with the product stream produced from the aromatics processing catalyst in step (i).

2 . The method of claim 1 ,
wherein, based on the total weight of the mixed aromatic feed stream, the mixed aromatic feed stream comprises:
from 0.1 wt % to 45 wt % olefins;
from 0.1 wt % to 25 wt % naphthenes;
from 0.1 wt % to 40 wt % naphtheno-olefins;
phenols in an amount from 10 ppm to 10 wt %; and/or
oxygenates in an amount from 10 ppm to 10 wt %.

3 . The method of claim 1 , wherein the mixed aromatic feed stream has a bromine number of at least 1 mg Br 2 /g of the mixed aromatic feed to less than 100 mg Br 2 /g of the mixed aromatic feed.

4 . The method of claim 1 , wherein the mixed aromatic feed stream comprises C 9-10 aromatics.

5 . The method of claim 1 , wherein the C 7− stream is fed to a second distillation column that fractionates the C 7− stream into a C 6− stream and a C 7 stream.

6 . The method of claim 5 , wherein at least a portion of the C 7 stream is recycled and combined with the mixed aromatic feed stream.

7 . The method of claim 1 , wherein the C 9+ stream is fed to a fourth distillation column that fractionates the C 9+ stream into a C 9-10 stream and a C 11+ stream, wherein the C 9-10 stream is recycled and combined with the mixed aromatic feed stream.

8 . The method of claim 1 , wherein at least a portion of the isomerization product stream is combined with the C 8 stream entering the isomer-recovery process unit.

9 . The method of claim 1 , wherein step (ii) comprises fractionating the product stream to separate a C 7 stream, a C 8 stream, and a C 9-10 stream, wherein the C 8 stream is fed to the isomer-recovery process unit, the C 7 stream is recycled and combined with the mixed aromatic feed stream, and the C 9-10 stream is recycled and combined with the mixed aromatic feed stream.

10 . The method of claim 1 , wherein step (ii) comprises fractionating the product stream to separate a C 7 stream, a C 8 stream, and a C 9+ stream, wherein the C 8 stream is fed to the isomer-recovery process unit, the C 7 stream is recycled and combined with the mixed aromatic feed stream, and the C 9+ stream is recovered as a product.

11 . The method of claim 1 , wherein the isomer-recovery process unit comprises an adsorption unit or a crystallization unit.

12 . The method of claim 1 , wherein the aromatics processing catalyst comprises an acid catalyst, which comprises aluminosilicates, tungstated aluminosilicates, silica-alumina phosphates, aluminum phosphates, amorphous silica alumina, zirconia, sulfated zirconia, tungstated zirconia, tungsten carbide, molybdenum carbide, titania, acidic alumina, phosphated alumina, tungstated alumina, phosphated silica, tungstated silica, tungstated titania, tungstated phosphate, niobia, sulfated carbons, phosphated carbons, acidic resins, heteropolyacids, tungstated heteropolyacid, inorganic acids, or a combination thereof; and wherein the acid catalyst comprises a metal, which comprises Cu, Ag, Au, Pt, Ni, Fe, Co, Ru, Rh, Zn, Ga, In, Pd, Ir, Re, Mn, Cr, Mo, W, Sn, Os, alloys, or a combination thereof.

13 . The method of claim 1 , wherein step (i) occurs at a temperature from 200° C. to 600° C., a pressure from 100 psig to 1500 psig, or a weight hourly space velocity (WHSV) from 0.1 to 10 mass feed/mass catalyst/hour, or wherein step (i) comprises feeding hydrogen in an amount of at least 0.1 mol of hydrogen per mol of mixed aromatic feed.

14 . A method for producing and separating an aromatic compound from a mixed aromatic feed stream, the method comprising:
(i) contacting an aqueous hydrocarbon feedstock comprising water and one or more oxygenate with a condensation catalyst to produce a condensation product stream comprising C 4+ compounds, wherein the C 4+ compounds comprise a C 4+ alcohol, a C 4+ ketone, a C 4+ alkane, a C 4+ alkene, a C 5+ cycloalkane, a C 5+ cycloalkene, an aryl, or a fused aryl; (ii) fractionating the condensation product stream to generate a light stream and a heavy stream, wherein the light stream comprises co-boiling non-aromatic contaminants for benzene or toluene, and the heavy stream is substantially free of co-boiling non-aromatic contaminants for benzene or toluene; (iii) recycling the light stream to the condensation catalyst; (iv) fractionating the heavy stream into a mixed aromatic feed comprising C 7-10 aromatics, and fractionating the mixed aromatic feed into a C 7-10 stream and a C 11+ stream; and (v) subjecting at least a portion of the C 7-10 stream to the method of claim 1 , thereby separating the aromatic compound.

15 . The method of claim 14 wherein step (iv) occurs at a temperature from 200° C. to 600° C. and a pressure from 100 psig to 1500 psig and at a weight hourly space velocity (WHSV) from 0.1 to 10 mass feed/mass catalyst/hour.

Assignees

• Virent Inc

Inventors

• Blommel Paul G
• Van Straten Matthew
• Dally Brice

Classifications

• C07C7/09

  by fractional condensation · CPC title

• C07C7/05

  with the aid of auxiliary compounds · CPC title

• C07C6/12 Primary

  of exclusively hydrocarbons containing a six-membered aromatic ring · CPC title

• C10G2400/30

  Aromatics · CPC title

• C10G2300/1096

  Aromatics or polyaromatics · CPC title