Method for Preparing P-Xylene by Biomass Conversion

Patent metadata

Field	Value
Publication number	US-2024254064-A1
Application number	US-202218561473-A
Country	US
Kind code	A1
Filing date	May 20, 2022
Priority date	May 21, 2021
Publication date	Aug 1, 2024
Grant date	—

Abstract

A method for preparing paraxylene by biomass conversion includes the following steps: (1) contacting a biomass starting material with a hydrogenation catalyst for reaction in a multiphase system formed by an organic solvent, an inorganic salt and water, in the presence of hydrogen as a hydrogen source, and separating the resulting product to obtain an organic phase comprising 2,5-hexanedione; and (2) contacting the organic phase comprising 2,5-hexanedione obtained in the step (1) and ethylene with a molecular sieve catalyst for reaction to obtain paraxylene. The molecular sieve catalyst is at least one selected from the group consisting of aluminophosphate molecular sieves and SCM-14 molecular sieves.

First claim

1 . A method for preparing a substituted or unsubstituted monocyclic aromatic hydrocarbon from a substituted or unsubstituted furan, comprising the steps of:
contacting an organic phase comprising a substituted or unsubstituted furan as starting material with ethylene and a molecular sieve catalyst for reaction to obtain a substituted or unsubstituted monocyclic aromatic hydrocarbon, wherein the molecular sieve catalyst comprises an SCM-X molecular sieve optionally doped with an element A that is at least one selected from the group consisting of Sn, Zr and Al, and X is 14 or 15.

2 . The method of claim 1 , wherein the SCM-X molecular sieve has a schematic chemical composition as represented by formula “mSiO 2 ·nGeO 2 ”, wherein 1≤m/n≤30, preferably 0.5≤m/n≤20, further preferably 2≤ m/n≤10.

3 . The method according to claim 1 , wherein the organic phase comprises an organic solvent selected from the group consisting of n-hexane, n-heptane, n-octane, tetrahydrofuran, 1,4-dioxane, cyclohexane and methyl isobutyl ketone.

4 . The method according to claim 1 , wherein the substituted or unsubstituted furan used as starting material has a structure represented by the following formula (I):

wherein R1, R2, R3 and R4 are each independently selected from H and C1-C6 alkyl, preferably each independently selected from H and C1-C4 alkyl, and further preferably at least one of R1, R2, R3 and R4 is not H;
with a proviso that the total number of carbon atoms of R1, R2, R3 and R4 is not greater than 8, preferably not greater than 6.

5 . The method according to claim 1 , wherein the substituted or unsubstituted furan is methylfuran and the substituted or unsubstituted monocyclic aromatic hydrocarbon is toluene.

6 . The method according to claim 5 , wherein the molecular sieve catalyst is an A-SCM-X molecular sieve, wherein A in the A-SCM-X molecular sieve is at least one selected from the group consisting of Sn, Zr, and Al, and X is 14 or 15.

7 . The method according to claim 6 , wherein the content of A component, calculated as oxide, in the A-SCM-X molecular sieve is not less than 0.5 wt %, preferably from 0.8 wt % to 3.5 wt %, more preferably from 1.2 wt % to 3.2 wt %; and/or
the Lewis acid content of the A-SCM-X molecular sieve is 30-500 μmol·g −1 , preferably 50-300 μmol·g −1 , and more preferably 83-292 μmol·g −1 ; and/or the ratio of Lewis/Bronst acid of the A-SCM-X molecular sieve is 0.5-10, preferably 0.6-5, and more preferably 0.6-2.1; and/or the A-SCM-X molecular sieve is Sn—SCM-14, Sn—SCM-15, Zr—SCM-14, Zr—SCM-15, Al-SCM-14 or Al-SCM-15 molecular sieve.

8 . The method according to claim 6 , wherein:
the A-SCM-X molecular sieve has a schematic chemical composition represented by the formula “mSiO 2 ·nGeO 2 ·pAO 2 ”, wherein 1≤m/n≤30, preferably 2≤m/n≤10, more preferably 3.5≤m/n≤8.7; 20≤m/p≤200, preferably 30≤m/p≤150, more preferably 30≤m/p≤96; and/or the A component is incorporated in the framework of the molecular sieve.

9 . The method according to claim 5 , wherein:
the conditions of the contacting and reaction include: a reaction temperature of 180-300° C., preferably 210-270° C.; and/or a reaction time of 4-72 h, preferably 10-50 h; and/or a reaction pressure of 1-8 MPa, preferably 2-5 MPa.

10 . The method according to claim 5 , wherein:
the contacting is carried out in the presence of an organic solvent that is one or more selected from the group consisting of n-heptane, n-octane, tetrahydrofuran, methyl isobutyl ketone and cyclohexane; and/or the mass ratio of methylfuran to catalyst is 0.2-8:1, preferably 0.5-6:1, and preferably 0.8-2:1; and/or the mass ratio of the organic solvent to methylfuran is 10-80:1, preferably 20-50:1; and/or the ethylene is dilute ethylene, the reaction system is introduced with dilute ethylene, the concentration of the dilute ethylene is 10-25 v %, and other gas in the dilute ethylene is inert gas.

11 . The method according to claim 1 , wherein the substituted or unsubstituted furan is 2,5-dimethylfuran and the substituted or unsubstituted monocyclic aromatic hydrocarbon is paraxylene.

12 . The method according to claim 11 , wherein the molecular sieve catalyst is an SCM-X molecular sieve comprising no doping element A;
preferably, the SCM-X molecular sieve is an SCM-14 molecular sieve having a schematic chemical composition represented by the formula “SiO 2 ·1/nGeO 2 ”, wherein n≤30, preferably 0.5≤n≤20, more preferably 1≤n≤10, and further preferably 2≤n≤8.

13 . The method according to claim 11 , wherein the conditions of the contacting and reaction include:
a pressure of 0.5-8 MPa, preferably 1-5 MPa; a reaction temperature of 160-340° C., preferably 200-300° C.; and/or a reaction time of 6-64 h, preferably 8-48 h.

14 . The method according to claim 11 , wherein the contacting is carried out in the presence of an organic solvent, and the organic solvent comprises one or more selected from the group consisting of n-hexane, n-heptane, n-octane, tetrahydrofuran, 1,4-dioxane, and cyclohexane;
the mass ratio of the starting material to the catalyst is 0.5-20.0:1, preferably 1.0-8.0:1; and/or the mass ratio of the organic solvent to the starting materials is 5-50:1, preferably 10-20:1.

15 . A method for preparing para-xylene, comprising the steps of:
contacting an organic phase comprising 2,5-hexanedione and ethylene with a molecular sieve catalyst for reaction to produce paraxylene, wherein the molecular sieve catalyst comprises an SCM-X molecular sieve, and X is 14 or 15; preferably, the SCM-X molecular sieve is an SCM-14 molecular sieve having a schematic chemical composition represented by the formula “SiO 2 ·1/nGeO 2 ”, wherein n≤30, preferably 0.5≤n≤20, more preferably 1≤n≤10, and further preferably 2≤n≤8, and preferably the conditions for the contacting and reaction include: an ethylene pressure of 0.5-5 MPa, preferably 1-4 MPa; and/or a reaction temperature of 160-340° C., preferably 200-300° C.; and/or a reaction time of 6-64 h, preferably 12-48 h.

16 . (canceled)

17 . The method according to claim 15 , comprising the steps of:
(1) contacting a biomass starting material with a hydrophobic hydrogenation catalyst for reaction in a two-phase solvent system comprising an organic solvent phase and an aqueous solution phase, in the presence of hydrogen as a hydrogen source, and separating the resulting product to obtain the organic phase comprising 2,5-hexanedione; wherein the pH of the aqueous solution phase is about 6.5-8.5, preferably 7-8; and (2) contacting the organic phase comprising 2,5-hexanedione and ethylene with a molecular sieve catalyst to produce para-xylene, preferably, in step (1), the aqueous solution phase comprises an inorganic salt dissolved therein, the anion and cation of the inorganic salt being derived from Group VIIA elements and Group IA elements, respectively; preferably, the Group VIIA element is at least one selected from the group consisting of Cl and Br, and/or the Group IA element is at least one selected from the group consisting of Li, Na, and K.

18 . (canceled)

19 . The method according to claim 17 , wherein in step (1),
the organic solvent of the organic solvent phase is one of 1,2-dichloroethane, 1,4-dioxane, methyl isobutyl ketone, tetrahydrofuran, γ-valerolactone and toluene, or a mixture of two or more of them, preferably one or two of 1,4-dioxane and tetrahydrofuran; and/or the mass r

Assignees

• China Petroleum & Chem Corp
• Shanghai Res Inst Petrochemical Tech Sinopec

Inventors

• Yang Weimin
• Li Xiangcheng
• Wang Zhendong
• Feng Xinqiang
• Han Xiao
• Xu Rui
• Liu Chuang
• Yuan Zhiqing
• Qiao Jian

Classifications

• B01J29/047

  Germanosilicates; Aluminogermanosilicates (B01J29/005 takes precedence) · CPC title

• C07C2529/70

  of types characterised by their specific structure not provided for in groups C07C2529/08 - C07C2529/65 · CPC title

• C07C2529/84

  Aluminophosphates containing other elements, e.g. metals, boron · CPC title

• B01J29/83

  Aluminophosphates [APO compounds] · CPC title

• C07C2/867

  the non-hydrocarbon is an aldehyde or a ketone · CPC title