Process for the recovery of furfural

• US 10,501,430 B2
• Filed: 10/30/2017
• Issued: 12/10/2019
• Est. Priority Date: 11/01/2016
• Status: Active Grant

• Current Assignee: Shell USA Incorporated (Shell Plc)
• Original Assignee: Shell Oil Company (Shell Plc)
• Inventors: Chheda, Juben Nemchand, Lange, Jean Paul Andre Marie Joseph Ghislain
• Primary Examiner(s): Rozof, Timothy R
• Application Number:
  US16/346,317
• Publication Number:
  US 20190276422A1
• Time in Patent Office: 771 Days
• CPC Class Codes: B01D 3/36 Azeotropic distillation
• CPC Class Codes: C07D 307/48 Furfural
• CPC Class Codes: C07D 307/50 Preparation from natural products

Abstract

Disclosed is a process for the extraction of furfural including: (a) subjecting a composition comprising furfural, water, at least one inorganic acid, at least one organic acid and a solvent mixture comprising an aromatic solvent and an oxygenate solvent, to a first separation step providing: (i) a first organic phase; (b) subjecting the first organic phase to a first distillation step providing: (i) a first top stream comprising furfural and a portion of the at least one organic acid; (c) subjecting the first top stream from step (b) to a second separation step providing: (i) a second top stream enriched with furfural; (d) subjecting the second top stream from step (c) to a second distillation step providing: (i) a third top stream comprising a furfural-water azeotrope, and (ii) a third bottom stream comprising furfural.

Claims

1. A process for the extraction of furfural from a composition comprising furfural, water, at least one organic acid and a solvent mixture comprising an aromatic solvent and an oxygenate solvent wherein each of the solvents in the solvent mixture has a boiling point higher than of furfural, said process comprising:

(a) subjecting the composition to a first liquid-liquid separation step to provide a first organic phase comprising the solvent mixture, a portion of the furfural and a portion of the at least one organic acid, and a first aqueous phase comprising the remainder of the furfural, and the remainder of the at least one organic acid;

(b) subjecting the first organic phase to a first distillation step to provide a first top stream comprising furfural and a portion of the at least one organic acid, and a first bottom stream comprising the solvent mixture;

(c) subjecting the first top stream from step (b) to a second liquid-liquid separation step to provide a second top stream enriched with furfural and a portion of the at least one organic acid, and a second bottom stream comprising the remainder of the furfural and a portion of the at least one organic acid; and

(d) subjecting the second top stream from step (c) to a second distillation step to provide a third top stream comprising a furfural-water azeotrope and a portion of the at least one organic acid, and a third bottom stream comprising furfural.

2. The process according to claim 1, wherein the composition is derived from a product stream of a pentose dehydration step wherein a pentose feed stream is dehydrated.

3. The process according to claim 2, wherein the pentose feed stream is derived from the hydrolysis of a lignocellulosic biomass.

4. The process according to claim 1, wherein the aromatic solvent is selected from the group consisting of 1-ethyl-2,3-dimethylbenzene, 1-ethyl-2,5-dimethylbenzene, 1-ethyl-2,4-dimethylbenzene, 1-ethyl-3,4-dimethylbenzene, 1,2,3,5-tetramethylbenzene, 1,2,3,4-tetramethylbenzene, 1,2,4,5-tetramethylbenzene, naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, n- and sec-propyl-methyl benzenes (with the methyl group located in 2-, 3-, 4- or 5-position) n- and sec-butyl benzene, n- and sec-pentyl benzene, or any combination thereof.

5. The process according to claim 1, wherein the oxygenate solvent is selected from the group consisting of:

propyl guaiacol;

propyl syringol;

guaiacyl propanol, syringyl propanol;

nonyl phenol;

o-, m-, p-substituted cresols;

guaiacol;

2-methoxy-4-propylphenol;

eugenol;

2,6-xylenol;

sec-butyl phenol and 2,5-xylenol; and

any combination thereof.

6. The process according to claim 1, wherein the solvent mixture comprises a phenolic to aromatic volume ratio of in the range of from 20:

80 to 80;

20.

7. The process according to claim 1, wherein the solvent mixture comprises a phenolic to aromatic volume ratio of 30:

70.

8. The process according to claim 1, wherein the second bottom stream of step (c) is subjected to a third distillation step to provide a fourth top stream comprising a furfural-water azeotrope, and a fourth bottom stream comprising water and a portion of the at least one organic acid.

9. The process according to claim 1, wherein the first aqueous phase of step (a) and a portion of the first bottom stream of step (b) are conveyed to a third liquid-liquid separator and subjected to a third liquid-liquid separation step to provide a fifth top stream comprising furfural and the solvent mixture, and an aqueous waste stream comprising water and at least one organic acid.

10. The process according to claim 1, wherein the fifth top stream is recycled to the first distillation step.