Process for the preparation of bio-based toluene from methylfuran

Abstract

The present application relates to the field of catalysis technology, and particularly relates to a method for preparing bio-based toluene from methyl furan, which comprises: contacting methyl furan with ethylene in the presence of optional organic solvent, wherein the catalyst contains A-SCM-X molecular sieve, A in the A-SCM-X molecular sieve is selected from at least one of Sn, Zr and Ti, and X is 14 or 15. The present application has outstanding cycle stability by using A-SCM-X molecular sieve as the catalyst, and the catalyst does not deactivate after being used for four cycles.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of catalysis technology, in particular, to a method for preparing bio-based toluene from methylfuran. BACKGROUND

[0002] Under the background of global climate and environmental crisis caused by the increasing depletion of fossil resources and excessive emission of CO2, it has become a global consensus to turn to low-carbon circular economy, and bio-based industry is an important part of it. Compared with traditional petrochemical products, bio-based products including biofuels, chemicals and materials have the advantages of carbon emission reduction, renewability and development promotion, so many scholars focus on using biomass to supplement fossil energy. Aromatic hydrocarbon is an important petrochemical product, and toluene as an important aromatic hydrocarbon is used as a solvent for oil, resin, natural rubber and synthetic rubber, coal tar, asphalt, cellulose acetate, and is also used as a solvent for cellulose paint and varnish, and is used as a solvent for photographic plate and ink. Toluene is also an important raw material for organic synthesis, especially chlorobenzoyl and phenyl, saccharin, trinitrotoluene and many dyes. It is also a component of aviation and automobile gasoline.

[0003] Alternative methods for the production of toluene from bio-based methyl furan (MF) and ethylene have been studied for the green and sustainable production of toluene from biomass resources. Furfural can be prepared from biomass by hydrolysis and dehydration, and can be converted into methyl furan by further hydrogenolysis (Green Chemistry. 2018, 20, 2027-2037). The group of Jungho Jae (Fuel, 2016, 182, 588-596) used metal chlorides to catalyze the reaction of methyl furan and ethylene at 250℃ for 24h. The conversion of methyl furan was complete, and the yield of toluene was as high as 75%. However, the metal chloride catalysts caused a certain degree of equipment corrosion, and brought about environmental pollution and high separation costs. Subsequently, the group of Dauenhauer (Green Chemistry. 2014, 16, 585-588; Applied Catalysis B: Environmental. 2016, 180, 487-496) studied the influence of different molecular sieves on the reaction performance. The experimental results showed that the effect was best when using H-Beta molecular sieve as the catalyst. The selectivity of toluene was only 46% at the highest under the reaction at 250℃, and a large amount of polymers were produced, which increased the cost of product purification and separation, and was difficult to meet the demand of large-scale production. At the same time, pure ethylene was used as the raw material in the above reported experiments, while the dilute ethylene in the fluid catalytic cracking dry gas of the refinery has a low concentration (10(v)%-25(v)%), and is difficult to utilize. In the past, it was usually burned as fuel, wasting valuable resources. If this part of ethylene resources can be effectively utilized to realize the high value conversion of dilute ethylene resources, especially in the preparation of bio-based chemicals, it has broad development prospects. SUMMARY

[0004] In summary, in the prior art, the main problems of the preparation of toluene from bio-based methyl furan and ethylene reaction are low reaction activity, poor process economic benefit or poor stability, etc. In order to solve the above technical problems, the present application provides a method for preparing bio-based toluene from methyl furan. The A-SCM-X molecular sieve described in the present application is used as a catalyst, which can realize the efficient conversion of methyl furan under mild reaction conditions, and the selectivity of the product toluene is high.

[0005] The present application provides a method for preparing bio-based toluene from methyl furan, which comprises:

[0006] In the presence of an optional organic solvent, methyl furan is contacted with ethylene, and the catalyst contains the A-SCM-X molecular sieve described in the present application, wherein A in the A-SCM-X molecular sieve is at least one selected from Sn, Zr and Ti, and X is 14 or 15.

[0007] Preferably, the catalyst is an A-SCM-X molecular sieve or a shaped catalyst of an A-SCM-X molecular sieve, preferably the catalyst is an A-SCM-X molecular sieve.

[0008] Preferably, the contacting reaction is carried out at a reaction temperature of 180-300℃, preferably at a reaction temperature of 210-270℃; and / or for a reaction time of 4-72h, preferably for a reaction time of 10-50h; and / or at a reaction pressure of 1-8MPa, preferably at a reaction pressure of 2-5MPa.

[0009] Preferably, the contacting is carried out in the presence of an organic solvent selected from one or more of n-heptane, n-octane, tetrahydrofuran, methyl isobutyl ketone and cyclohexane.

[0010] Preferably, the catalyst is an A-SCM-X molecular sieve.

[0011] Preferably, the mass ratio of methylfuran to catalyst is 0.2-8:1, preferably 0.5-6:1, preferably 0.8-2:1.

[0012] Preferably, the mass ratio of organic solvent to methylfuran is 10-80:1, preferably 20-50:1.

[0013] Preferably, ethylene is used in the form of dilute ethylene, and the dilute ethylene is charged into the reaction system, the concentration of the dilute ethylene is 10v%-25v%, and the other gas of the dilute ethylene is an inert gas.

[0014] Preferably, the content of the A component in the A-SCM-X molecular sieve is not less than 0.5wt%, preferably 0.8wt%-3.5wt%, more preferably 1.2-3.2wt%.

[0015] Preferably, the Lewis acid amount of the A-SCM-X molecular sieve is 30-500μmol·g -1 , preferably 50-300μmol·g -1 , more preferably 83-292μmol·g -1 .

[0016] Preferably, the Lewis / Bronst acid ratio of the A-SCM-X molecular sieve is 0.5-10, preferably 0.6-5, more preferably 0.6-2.1.

[0017] Preferably, the A-SCM-X molecular sieve is a Sn-SCM-14, Sn-SCM-15, Zr-SCM-14, Zr-SCM-15, Ti-SCM-14 or Ti-SCM-15 molecular sieve.

[0018] Preferably, the A-SCM-X molecular sieve has a schematic chemical composition as shown in the formula “mSiO2·nGeO2·pAO2”; 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 component A is located in the framework of the molecular sieve.

[0019] Preferably, the preparation method of the A-SCM-X molecular sieve includes:

[0020] (1) The SCM-X molecular sieve is mixed with an acidic organic solution for pretreatment, washing, drying and calcination to obtain a solid;

[0021] (2) The solid is mixed with a precursor solution containing metal source A, dried and calcined.

[0022] Preferably, in the acidic organic solution, the organic solvent is selected from at least one of dimethyl sulfoxide, tetrahydrofuran, 1,4-dioxane, methanol, and ethanol, and is preferably dimethyl sulfoxide.

[0023] Preferably, the acid is selected from organic acids and / or inorganic acids, and more preferably, the acid is selected from at least one of oxalic acid, hydrochloric acid, sulfuric acid, nitric acid and acetic acid, with hydrochloric acid being the most preferred.

[0024] Preferably, the acid concentration in the acid-containing organic solution is 0.001 to 1 mol / L, more preferably 0.005 to 0.1 mol / L.

[0025] Preferably, the solid-liquid mass ratio of SCM-X molecular sieve to acidic organic solution is 1:10-40, more preferably 1:15-20.

[0026] Preferably, the precursor containing the metal source A is selected from at least one of the following: an organometallic complex containing A, a metal salt containing A, and a metal hydroxide containing A.

[0027] Preferably, the mass ratio of A to SCM-X molecular sieve in the precursor solution containing metal A source is 1:20-200; more preferably, it is 1:30-83.

[0028] Preferably, the pretreatment conditions in step (1) include: a temperature of 30–100°C, more preferably 35–90°C, and more preferably 40–80°C; and / or a time of 0.25–24 hours, more preferably 0.5–18 hours, and more preferably 0.75–12 hours; and / or the calcination conditions in steps (1) and (2) each include: a calcination temperature of 300–650°C; and / or a calcination time of 1–12 hours; and / or a calcination atmosphere of oxygen or air.

[0029] This invention utilizes A-SCM-X molecular sieve as a catalyst, exhibiting outstanding cycle stability; no catalyst deactivation was observed after four cycles.

[0030] This invention utilizes A-SCM-X molecular sieves, especially Sn-SCM-14 or Zr-SCM-14 molecular sieves, which have high activity and stability. Under mild reaction conditions, it can achieve efficient conversion of methylfuran with high selectivity for the product toluene. Attached Figure Description

[0031] Figure 1 The image shows the UV-Vis absorption spectrum of the Sn-SCM-14 molecular sieve obtained in Example 1.

[0032] Figure 2 The image shows the X-ray photoelectron spectrum (XPS) of the Sn-SCM-14 molecular sieve obtained in Example 1.

[0033] Figure 3 The image shows the pyridine adsorption infrared spectrum (Py-FTIR) of the Sn-SCM-14 molecular sieve obtained in Example 1.

[0034] Figure 4 The XRD pattern of the Sn-SCM-14 molecular sieve obtained in Example 1;

[0035] Figure 5 The UV-Vis absorption spectrum of the Zr-SCM-14 molecular sieve obtained in Example 6 is shown.

[0036] Figure 6 The image shows the X-ray photoelectron spectrum (XPS) of the Zr-SCM-14 molecular sieve obtained in Example 6. Detailed Implementation

[0037] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0038] This invention provides a method for preparing bio-based toluene from methyl furan, the method comprising:

[0039] In the presence of an optional organic solvent, methylfuran is reacted with ethylene. The catalyst contains the A-SCM-X molecular sieve described in this invention, wherein A in the A-SCM-X molecular sieve is selected from at least one of Sn, Zr, and Ti, and X is 14 or 15. Using the A-SCM-X molecular sieve described in this invention as a catalyst, the reaction of ethylene with methylfuran to produce toluene can achieve highly efficient conversion of methylfuran using dilute ethylene as a raw material and under mild reaction conditions. The selectivity for the product toluene is also very high, with low by-product content. Furthermore, the A-SCM-X molecular sieve exhibits outstanding stability during recycling.

[0040] According to the present invention, the objective of the present invention can be achieved by the catalyst containing the A-SCM-X molecular sieve described herein. Preferably, the catalyst is an A-SCM-X molecular sieve or a shaped catalyst of an A-SCM-X molecular sieve, and more preferably, the catalyst is an A-SCM-X molecular sieve.

[0041] In this invention, the reaction conditions can be selected from a wide range, and can be specifically determined according to the reaction requirements. According to this invention, preferably, the conditions for the contact reaction include: a reaction temperature of 180-300℃, and more preferably a reaction temperature of 210-270℃.

[0042] According to the present invention, the contact reaction time can be determined based on the contact reaction temperature. Preferably, the contact reaction conditions include a reaction time of 4-72 hours, and more preferably a reaction time of 10-50 hours.

[0043] According to a preferred embodiment of the present invention, the conditions for the contact reaction include: a reaction pressure of 1-8 MPa, preferably a reaction pressure of 2-5 MPa.

[0044] According to a preferred embodiment of the present invention, the conditions for the contact reaction include: a reaction temperature of 180-300°C, preferably 210-270°C; a reaction time of 4-72 h, preferably 10-50 h; and a pressure of 1-8 MPa, preferably 2-5 MPa.

[0045] According to the present invention, the contact is carried out in the presence of an organic solvent. In the present invention, the amount of organic solvent can be selected from a wide range and can be determined according to the reaction requirements. Preferably, the organic solvent is selected from one or more of n-heptane, n-octane, tetrahydrofuran, methyl isobutyl ketone and cyclohexane.

[0046] According to a preferred embodiment of the present invention, the mass ratio of methylfuran to catalyst is 0.2-8:1, preferably 0.5-6:1, and more preferably 0.8-2:1. This facilitates substrate conversion and increases the selectivity of the target product.

[0047] According to a preferred embodiment of the present invention, the mass ratio of organic solvent to methylfuran is 10-80:1, preferably 20-50:1. This is beneficial to the conversion of the substrate and also increases the selectivity of the target product.

[0048] According to a preferred embodiment of the present invention, dilute ethylene is used, and the reaction system is charged with dilute ethylene at a concentration of 10 vol%-25 vol%, while the other gases in the dilute ethylene reaction are inert gases. Using the A-SCM-X molecular sieve described in this invention as a catalyst, the reaction of ethylene with methylfuran to prepare toluene achieves highly efficient conversion of methylfuran under mild reaction conditions and with dilute ethylene as a raw material. The selectivity for the product toluene is also very high, and the content of by-products is low. Furthermore, the A-SCM-X molecular sieve also exhibits outstanding stability during recycling.

[0049] According to a preferred embodiment of the present invention, the content of component A in the A-SCM-X molecular sieve, calculated as oxides, is not less than 0.5 wt%, preferably 0.8 wt%-3.5 wt%, and more preferably 1.2-3.2 wt%. Therefore, efficient conversion of methylfuran can be achieved under mild reaction conditions, with very high selectivity for the product toluene and low byproduct content.

[0050] According to a preferred embodiment of the present invention, the Lewis acidity of the A-SCM-X molecular sieve is 30-500 μmol·g. -1 Preferably, it is 50-300 μmol·g -1 More preferably, it is 83-292 μmol·g -1 Therefore, under mild reaction conditions, the efficient conversion of methylfuran can be achieved, with very high selectivity for the product toluene and low content of byproducts.

[0051] According to a preferred embodiment of the present invention, the Lewis / Bronst acid ratio of the A-SCM-X molecular sieve is 0.5-10, preferably 0.6-5, and more preferably 0.6-2.1. Therefore, efficient conversion of methylfuran can be achieved under mild reaction conditions, with very high selectivity for the product toluene and low byproduct content.

[0052] According to a preferred embodiment of the present invention, the A-SCM-X molecular sieve is Sn-SCM-14, Sn-SCM-15, Zr-SCM-14, Zr-SCM-15, Ti-SCM-14, or Ti-SCM-15 molecular sieve.

[0053] According to a preferred embodiment of the present invention, the A-SCM-X molecular sieve has an illustrative chemical composition as shown in the formula "mSiO2·nGeO2·pAO2"; 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.

[0054] According to a preferred embodiment of the present invention, component A is located within the framework of the molecular sieve. Therefore, efficient conversion of methylfuran can be achieved under mild reaction conditions, with very high selectivity for the product toluene and low byproduct content.

[0055] This invention provides a high-purity A-SCM-X molecular sieve product. The molecular sieve has a schematic chemical composition as shown in the formula "mSiO2·nGeO2·pAO2", which is unprecedented in the art. The state of A is determined by XPS (X-ray photoelectron spectroscopy) or ultraviolet Raman spectroscopy. The A component in the A-SCM-X molecular sieve provided by this invention is effectively integrated into the molecular sieve framework, and the pyridine desorption infrared spectrum shows that the A-SCM-X molecular sieve has a suitable amount of Lewis acid and a Lewis / Bronst acid ratio.

[0056] In this invention, all A-SCM-X molecular sieves possessing the aforementioned properties are considered as the A-SCM-X molecular sieves described in this invention, and all A-SCM-X molecular sieves possessing the aforementioned properties can achieve the objectives of this invention. There are no special requirements for the preparation method. For this invention, a method for preparing the A-SCM-X molecular sieve described in this invention is provided, the method comprising:

[0057] (1) The SCM-X molecular sieve is mixed with an acidic organic solution for pretreatment, washing, drying and calcination to obtain a solid;

[0058] (2) The solid is mixed with a precursor solution containing metal source A, dried and calcined.

[0059] According to the present invention, any SCM-X molecular sieve in the art can be used as a raw material for the present invention, such as SCM-14 molecular sieve and / or SCM-15 molecular sieve. According to one embodiment of the present invention, preferably, the SCM-14 molecular sieve and its preparation method are further described in Chinese patent application CN109081360A, and the SCM-15 molecular sieve and its preparation method are further described in Chinese patent application CN109081359A, which are incorporated herein by reference in their entirety.

[0060] According to a preferred embodiment of the present invention, the organic solvent in the acidic organic solution can be selected from a wide range, such as toluene, dimethyl sulfoxide, dimethylformamide, tetrahydrofuran, acetonitrile, 1,4-dioxane, methanol, ethanol, and methyl isobutyl ketone. For the present invention, the organic solvent is preferably selected from at least one of dimethyl sulfoxide, tetrahydrofuran, 1,4-dioxane, methanol, and ethanol, and is preferably dimethyl sulfoxide.

[0061] According to a preferred embodiment of the present invention, the acid is selected from organic acids and / or inorganic acids, preferably selected from at least one of oxalic acid, hydrochloric acid, sulfuric acid, nitric acid and acetic acid, and more preferably hydrochloric acid.

[0062] According to a preferred embodiment of the present invention, the acid concentration in the acid-containing organic solution is 0.001–1 mol / L, preferably 0.005–0.1 mol / L. Therefore, efficient conversion of methylfuran can be achieved under mild reaction conditions, with very high selectivity for the product toluene and low byproduct content.

[0063] According to the present invention, the solid-liquid mass ratio of SCM-X molecular sieve to acidic organic solution is 1:10-40, preferably 1:15-20. The A-SCM-X molecular sieve prepared thereby is beneficial for improving activity, selectivity, and cycle stability. Specifically, when applied to the conversion of methylfuran, it can improve the conversion rate of methylfuran and the selectivity for toluene.

[0064] According to the present invention, the washing and drying conditions of the A-SCM-X molecular sieve after pretreatment in the acidic organic solution are conventionally selected in the art. For the present invention, preferably, the pretreated A-SCM-X molecular sieve is washed until neutral and then dried.

[0065] In this invention, there are no special requirements regarding the type of A-containing metal source in the precursor. Preferably, the A-containing metal source precursor is selected from at least one of A-containing organometallic complexes, A-containing metal salts, and A-containing metal hydroxides. For example, when A is tin, it can be at least one of tin-containing organometallic complexes, tin salts, and tin hydroxides; as a tin-containing organometallic complex, tributyltin chloride (C... 12 H 27 ClSn), dimethyltin dichloride (C2H6Cl2Sn), di-tert-butyltin dichloride [(CH3)3C]2SnCl2, stannous oxalate (SnC2O4), dibutyltin maleate (C 12 H 20Examples of zirconium-containing organometallic complexes include dicyclopentadienyl zirconium dichloride (Cp2ZrCl2), dicyclopentadienyl zirconium chloride hydride (Cp2ZrHCl), dicyclopentadienyl dimethyl zirconium [Cp2Zr(CH3)2], dicyclopentadienyl dihydrozirconium (Cp2ZrH2), and bis(n-butylcyclopentadienyl)zirconium dichloride [(C4H9)C5H4]2ZrCl2, but these are not limited to these examples. Examples of titanium-containing organometallic complexes include dichlorotitanium (C4Sn). 10 H 10 Cl2Ti), bis(pentamethylcyclopentadiene)titanium dichloride (C 20 H 32 Cl2Ti), but not limited to this.

[0066] According to the present invention, the mass ratio of A to SCM-X molecular sieve in the precursor solution containing the A metal source is 1:20-200; more preferably 1:30-83. The A-SCM-X molecular sieve prepared thereby improves cycle stability. Thus, efficient conversion of methylfuran can be achieved under mild reaction conditions, with very high selectivity for the product toluene and low byproduct content.

[0067] According to the present invention, the pretreatment conditions can be conventionally selected. For the present invention, preferably, the pretreatment conditions in step (1) include: a temperature of 30 to 100°C, more preferably a temperature of 35 to 90°C, and more preferably a temperature of 40 to 80°C.

[0068] According to the present invention, the pretreatment time can be determined based on the reaction temperature. For the present invention, preferably, the pretreatment conditions in step (1) include: a time of 0.25 to 24 hours, more preferably 0.5 to 18 hours, and more preferably 0.75 to 12 hours.

[0069] According to the present invention, the roasting conditions can be conventionally selected. For the present invention, preferably, the roasting conditions in steps (1) and (2) each include: a roasting temperature of 300 to 650°C.

[0070] According to the present invention, the roasting time can be determined according to the roasting temperature. For the present invention, preferably, the roasting conditions in steps (1) and (2) each include: roasting time of 1 to 12 hours.

[0071] According to a preferred embodiment of the present invention, the roasting atmosphere is oxygen or air.

[0072] According to a preferred embodiment of the present invention, the pretreatment conditions in step (1) are 30-100°C for 0.25-24 hours, preferably 35-90°C for 0.5-18 hours, and more preferably 40-80°C for 0.75-12 hours.

[0073] According to a preferred embodiment of the present invention, the calcination conditions in the preparation method of the A-SCM-X molecular sieve are: calcination at 300-650°C for 1-12 hours, and the calcination atmosphere is oxygen or air.

[0074] In this invention, the reaction product toluene and the reaction substrate methylfuran were analyzed qualitatively and quantitatively using gas chromatography-mass spectrometry (GC-MS). The GC-MS system was an Agilent 7890A from Agilent Technologies, USA, with an HP-INNOWax capillary column (60m, 0.32mm). The gas chromatograph was an Agilent 7890B, with a flame ionization detector (FID) and an HP-INNOWax capillary column (60m, 0.32mm).

[0075] In this invention, the pyridine adsorption infrared method (Nicolet Model 710 spectrometer) is used to determine the acid content, acid type, and acid strength of the catalyst. The specific operating steps are as follows: a) Sample pretreatment. The sample (approximately 30 mg) is compressed into a thin disc with a diameter of 13 mm and placed in an infrared sample cell. The sample is then pretreated in a vacuum chamber at 400°C for 1 hour. After the sample cell cools to room temperature, the infrared data of the sample is scanned as background. b) Pyridine adsorption. Pyridine vapor is introduced into the in-situ under room temperature and vacuum conditions until adsorption reaches equilibrium; the adsorption time is 1 hour. c) Pyridine desorption. After adsorption, a vacuum is applied at 100°C until the internal pressure no longer changes; the desorption time is 40 minutes, and the infrared absorption spectrum is scanned and recorded. The difference spectrum before and after pyridine adsorption is the obtained pyridine adsorption-infrared absorption spectrum. When the desorption temperature is 100°C, the acid content calculated from the spectrum is the total acid content.

[0076] The difference spectrum before and after pyridine adsorption is the obtained pyridine adsorption-infrared absorption spectrum. Based on the spectrum, a semi-quantitative calculation of the acidity of the sample was performed.

[0077]

[0078]

[0079] Where r and w are the diameter (cm) and mass (g) of the catalyst disc, respectively, and A is the integral absorbance value at the specified wavenumber peak based on the scanned pyridine adsorption-infrared absorption spectrum. IMEC is the integral molar extinction coefficient. L Version 2.22, IMEC B It is 1.67.

[0080] In this invention, the XRD measurement method for molecular sieve products is as follows: the phase composition of the sample is analyzed using a Rigaku Ultima IV X-ray powder diffractometer (Japan), with a CuKα ray source. Nickel filter, 2θ scanning range 2°-50°, operating voltage 35KV, current 25mA, scanning rate 10° / min.

[0081] In this invention, the ultraviolet-visible spectrum was measured on a UV-2550 from Shimadzu Corporation of Japan, with solid barium sulfate as a reference, and the wavelength range of the test was 200-800 nm.

[0082] In this invention, the element binding energy on the catalyst surface was measured on a Thermo X-ray photoelectron spectrometer (ESCA LAB-250), and the measured element signal was corrected using C1s = 284.6 eV as an internal standard.

[0083] In this invention, an inductively coupled plasma atomic emission spectrometer (ICP) of model Varian 725-ES is used to dissolve the sample in hydrofluoric acid to detect the element content.

[0084] In this invention, the formula for methylfuran conversion rate is:

[0085] The conversion rate of methylfuran (%) = (molar amount of methylfuran participating in the reaction) / (molar amount of methylfuran as the reaction substrate) × 100%.

[0086] In this invention, the formula for calculating the yield of toluene is as follows:

[0087] The yield % of the product toluene = (molar amount of toluene produced in the reaction) / (molar amount of the reaction substrate methylfuran) × 100%.

[0088] In this invention, the formula for calculating the selectivity of the product toluene is:

[0089] Selectivity of toluene as a product % = (molar amount of toluene produced in the reaction) / (molar amount of methylfuran produced in the reaction) × 100%.

[0090] To facilitate understanding of the present invention, the following embodiments are provided. However, these embodiments are merely for the purpose of helping to understand the present invention and should not be regarded as specific limitations of the present invention.

[0091] In the following examples, the process of synthesizing SCM-14 molecular sieve according to the preparation method in Example 1 of CN109081360A is as follows:

[0092] 10.08 g of deionized water, 3.045 g of organic template agent 4-pyrrolylpyridine (98 wt%), 1.674 g of germanium oxide (99 wt%), 1.0 g of hydrofluoric acid (40 wt%), and 6.0 g of silica sol (SiO2 40 wt%) were mixed evenly to obtain a reaction mixture. The material ratio (molar ratio) of the reaction mixture was: SiO2 / GeO2 = 2.5; template agent / SiO2 = 0.50; F / SiO2 = 0.50; H2O / SiO2 = 20. After being mixed evenly, the mixture was placed in a stainless steel reactor and aged in an 80°C water bath for 4 hours. Then, it was crystallized at 100°C for 2 days with stirring, and then crystallized at 170°C for 5 days. After crystallization, the sample was filtered, washed, and dried at 150°C for 8 hours to obtain a molecular sieve precursor with the schematic chemical composition of 0.21F·0.06Q·SiO2·1 / 3.7GeO2·0.02H2O. The precursor was then calcined in air at 550°C for 6 hours to obtain SCM-14 molecular sieve.

[0093] In the following examples, the process of synthesizing SCM-14 molecular sieve according to the preparation method in Example 2 of CN109081360A is as follows: The materials were fed according to the preparation method in Example 1 of CN109081360A, and the material ratio (molar ratio) of the reaction mixture was changed to: SiO2 / GeO2=3; template agent / SiO2=0.30; F / SiO2=0.30; H2O / SiO2=18; after being mixed evenly, it was loaded into a stainless steel reactor and aged in an 80°C water bath for 1 hour, then crystallized at 110°C for 1 day with stirring, and then crystallized at 165°C for 4 days to obtain SCM-14 molecular sieve.

[0094] In the following examples, the process of synthesizing SCM-15 molecular sieve according to the preparation method in Example 1 of CN109081359A is as follows:

[0095] 43.2 g of deionized water, 42.63 g of organic template agent 4-pyrrolylpyridine (98 wt%), 8.37 g of germanium oxide (99 wt%), 14.0 g of hydrofluoric acid (40 wt%), and 60.0 g of silica sol (SiO2 40 wt%) were mixed evenly to obtain a reaction mixture. The material ratio (molar ratio) of the reaction mixture was: SiO2 / GeO2 = 5; template agent / SiO2 = 0.70; F / SiO2 = 0.70; H2O / SiO2 = 12. After mixing evenly, the mixture was placed in a stainless steel reactor and aged in an 80°C water bath for 2 hours, followed by crystallization at 170°C for 5 days with stirring. After crystallization, the mixture was filtered, washed, and dried at 120°C for 12 hours to obtain SCM-15 molecular sieve.

[0096] Example 1

[0097] SCM-14 molecular sieve was synthesized according to the preparation method in Example 1 of CN109081360A. It was added to a 0.01 mol / L hydrochloric acid (30 wt%) dimethyl sulfoxide solution at a solid-liquid mass ratio of 1:20. The mixture was pretreated for 3 hours under stirring in a water bath at 60°C. The product was centrifuged and washed until the solution pH reached 7, then dried overnight at 110°C. Then, a Sn-containing organometallic precursor (CH3)2SnCl2 was added, with a Sn (theoretical amount of Sn in the organometallic precursor) to SCM-14 molecular sieve mass ratio of 1:49. The mixture was thoroughly ground in a mortar to obtain a uniformly dispersed mixture.

[0098] The product was dried in an oven at 110℃ and then calcined at 550℃ for 5 hours in air to obtain Sn-SCM-14 molecular sieve. The UV-Vis spectrum of the sample is shown below. Figure 1 As shown, by Figure 1 It can be seen that heteroatom tin species exist in the molecular sieve framework in a four-coordinate form, as shown in the XPS spectrum. Figure 2 As shown, this indicates that Sn successfully entered the framework of the SCM-14 molecular sieve; the pyridine desorption infrared spectrum of the sample is shown below. Figure 3 As shown, by Figure 3 It can be seen that this molecular sieve possesses both Bronst and Lewis acidic species. Inductively coupled plasma atomic emission spectrometry (ICP) determined the sample's Si / Ge ratio to be 5.2 (atomic ratio) and Si / Sn ratio to be 57 (atomic ratio). The Lewis acidity calculated from the pyridine desorption infrared spectrum is 210 μmol·g. -1 The Lewis / Bronst acid ratio was 0.8, and the tin content, calculated as oxides, was 2.0 wt%. The XRD pattern of the obtained Sn-SCM-14 molecular sieve is shown below. Figure 4 ,Depend on Figure 4 It can be seen that the tin species are evenly dispersed in the molecular sieve.

[0099] Example 2

[0100] SCM-14 molecular sieve was synthesized according to the preparation method in Example 1 of CN109081360A. It was added to a 0.02 mol / L hydrochloric acid (30 wt%) dimethyl sulfoxide solution at a solid-liquid mass ratio of 1:20. The mixture was pretreated for 1 hour under stirring in a water bath at 70°C. The product was centrifuged and washed until the solution pH = 7, then dried overnight at 110°C. Then, a Sn-containing organometallic precursor (CH3)2SnCl2 was added, with a Sn (theoretical amount of Sn in the organometallic precursor) to SCM-14 molecular sieve mass ratio of 1:33. The mixture was thoroughly ground in a mortar to obtain a uniformly dispersed mixture.

[0101] The product was dried in an oven at 110℃ and then calcined at 550℃ for 5 hours to obtain Sn-SCM-14 molecular sieve. The UV-Vis spectrum of the sample is similar to... Figure 1 Similarly, XPS spectra and Figure 2 Similarly, this indicates that Sn successfully entered the framework of the SCM-14 molecular sieve; the pyridine desorption infrared spectrum of the sample is shown below. Figure 3 Similarly, inductively coupled plasma atomic emission spectrometry (ICP) determined the sample's Si / Ge ratio to be 6.1 (atomic ratio) and Si / Sn ratio to be 39 (atomic ratio). The Lewis acid content, calculated from the pyridine desorption infrared spectrum, was 284 μmol·g. -1 The Lewis / Bronst acid ratio is 1.0, and the tin content, calculated as oxides, is 2.9 wt%.

[0102] Example 3

[0103] SCM-14 molecular sieve was synthesized according to the preparation method in Example 1 of CN109081360A. It was added to a dimethyl sulfoxide solution containing 0.01 mol / L nitric acid at a solid-liquid mass ratio of 1:15. The mixture was pretreated for 2 hours under stirring in a water bath at 40°C. The product was centrifuged and washed until the solution pH reached 7, then dried overnight at 110°C. Then, an organometallic precursor (CH3)2SnCl2 containing Sn was added, with a Sn (theoretical amount of Sn in the organometallic precursor) to SCM-14 molecular sieve mass ratio of 1:83. The mixture was thoroughly ground in a mortar to obtain a uniformly dispersed mixture.

[0104] The product was dried in an oven at 110℃ and then calcined at 550℃ for 5 hours to obtain Sn-SCM-14 molecular sieve. The UV-Vis spectrum of the sample is similar to... Figure 1 Similarly, XPS spectra and Figure 2 Similarly, this indicates that Sn successfully entered the framework of the SCM-14 molecular sieve; the pyridine desorption infrared spectrum of the sample is shown below. Figure 3 Similarly, inductively coupled plasma atomic emission spectrometry (ICP) determined the sample's Si / Ge ratio to be 5.4 (atomic ratio) and Si / Sn ratio to be 96 (atomic ratio). The Lewis acid content, calculated from the pyridine desorption infrared spectrum, was 124 μmol·g. -1 The Lewis / Bronst acid ratio is 0.6, and the tin content, calculated as oxides, is 1.2 wt%.

[0105] Example 4

[0106] SCM-14 molecular sieve was synthesized according to the preparation method in Example 2 of CN109081360A. It was added to a dimethyl sulfoxide solution containing 0.008 mol / L oxalic acid at a solid-liquid mass ratio of 1:15. The mixture was pretreated for 5 hours under stirring in a water bath at 60°C. The product was centrifuged and washed until the solution pH reached 7, then dried overnight at 110°C. Then, an organometallic precursor (CH3)2SnCl2 containing Sn was added, with a Sn (theoretical amount of Sn in the organometallic precursor) to SCM-14 molecular sieve mass ratio of 1:49. The mixture was thoroughly ground in a mortar to obtain a uniformly dispersed mixture.

[0107] The product was dried in an oven at 110℃ and then calcined at 550℃ for 5 hours to obtain Sn-SCM-14 molecular sieve. The UV-Vis spectrum of the sample is similar to... Figure 1 Similarly, XPS spectra and Figure 2 Similarly, this indicates that Sn successfully entered the framework of the SCM-14 molecular sieve; the pyridine desorption infrared spectrum of the sample is shown below. Figure 3 Similarly, inductively coupled plasma atomic emission spectrometry (ICP) determined the Si / Ge ratio of the sample to be 3.5 (atomic ratio) and the Si / Sn ratio to be 61 (atomic ratio). The Lewis acid content calculated from the pyridine desorption infrared spectrum was 187 μmol·g. -1 The Lewis / Bronst acid ratio is 0.8, and the tin content, calculated as oxides, is 2.0 wt%.

[0108] Example 5

[0109] SCM-14 molecular sieve was synthesized according to the preparation method in Example 2 of CN109081360A. It was added to a dimethyl sulfoxide solution containing 0.02 mol / L oxalic acid at a solid-liquid mass ratio of 1:20. The mixture was pretreated for 3 hours under stirring in a water bath at 70°C. The product was centrifuged and washed until the solution pH = 7, then dried overnight at 110°C. Then, an organometallic precursor (CH3)2SnCl2 containing Sn was added, with a Sn (theoretical amount of Sn in the organometallic precursor) to SCM-14 molecular sieve mass ratio of 1:60. The mixture was thoroughly ground in a mortar to obtain a uniformly dispersed mixture.

[0110] The product was dried in an oven at 110℃ and then calcined at 550℃ for 5 hours to obtain Sn-SCM-14 molecular sieve. The UV-Vis spectrum of the sample is similar to... Figure 1 Similarly, XPS spectra and Figure 2 Similarly, this indicates that Sn successfully entered the framework of the SCM-14 molecular sieve; the pyridine desorption infrared spectrum of the sample is shown below. Figure 3Similarly, inductively coupled plasma atomic emission spectrometry (ICP) determined the Si / Ge ratio of the sample to be 7.4 (atomic ratio) and the Si / Sn ratio to be 85 (atomic ratio). The Lewis acid content calculated from the pyridine desorption infrared spectrum was 153 μmol·g. -1 The Lewis / Bronst acid ratio is 0.7, and the tin content, calculated as oxides, is 1.6 wt%.

[0111] Example 6

[0112] SCM-14 molecular sieve was synthesized according to the preparation method in Example 1 of CN109081360A. It was added to a dimethyl sulfoxide solution containing 0.01 mol / L acetic acid at a solid-liquid mass ratio of 1:20. The mixture was pretreated for 6 hours under stirring in a water bath at 60°C. The product was centrifuged and washed until the solution pH reached 7, then dried overnight at 110°C. A Zr-containing organometallic precursor, Cp2ZrCl2, was then added, with a Zr (theoretical amount of Zr in the organometallic precursor) to SCM-14 molecular sieve mass ratio of 1:49. The mixture was thoroughly ground in a mortar to obtain a uniformly dispersed mixture.

[0113] The product was dried in an oven at 110℃ and then calcined at 550℃ for 5 hours to obtain Zr-SCM-14 molecular sieve. The UV-Vis spectrum of the sample is shown below. Figure 5 As shown, by Figure 5 It can be seen that the heteroatom zirconium species exist in the molecular sieve framework in a four-coordinate form, as shown in the XPS spectrum. Figure 6 As shown, this indicates that Zr successfully entered the framework of the SCM-14 molecular sieve; the pyridine desorption infrared spectrum of the sample is shown below. Figure 3 Similarly, inductively coupled plasma atomic emission spectrometry (ICP) determined the Si / Ge ratio of the sample to be 4.3 (atomic ratio) and the Si / Zr ratio to be 44 (atomic ratio). The Lewis acid content calculated from the pyridine desorption infrared spectrum was 237 μmol·g. -1 The Lewis / Bronst acid ratio is 0.9, and the zirconium content, calculated as oxides, is 2.0 wt%.

[0114] Example 7

[0115] SCM-14 molecular sieve was synthesized according to the preparation method in Example 2 of CN109081360A. It was added to a dimethyl sulfoxide solution containing 0.04 mol / L acetic acid at a solid-liquid mass ratio of 1:20. The mixture was pretreated for 3 hours under stirring in a water bath at 50°C. The product was centrifuged and washed until the solution pH = 7, then dried overnight at 110°C. A Zr-containing organometallic precursor, Cp2ZrCl2, was then added, with a Zr (theoretical amount of Zr in the organometallic precursor) to SCM-1 molecular sieve mass ratio of 1:35. The mixture was thoroughly ground in a mortar to obtain a uniformly dispersed mixture.

[0116] The product was dried in an oven at 110℃ and then calcined at 550℃ for 5 hours to obtain Zr-SCM-14 molecular sieve. The UV-Vis spectrum of the sample is similar to... Figure 5 Similarly, XPS spectra and Figure 6 Similarly, this indicates that Zr successfully entered the framework of the SCM-14 molecular sieve; the pyridine desorption infrared spectrum of the sample is shown below. Figure 3 Similarly, inductively coupled plasma atomic emission spectrometry (ICP) determined the Si / Ge ratio of the sample to be 7.9 (atomic ratio) and the Si / Zr ratio to be 33 (atomic ratio). The Lewis acid content calculated from the pyridine desorption infrared spectrum was 292 μmol·g. -1 The Lewis / Bronst acid ratio is 1.1, and the zirconium content, calculated as oxide, is 2.8 wt%.

[0117] Example 8

[0118] SCM-15 molecular sieve was synthesized according to the preparation method in Example 1 of CN109081359A. It was added to a dimethyl sulfoxide solution containing 0.01 mol / L hydrochloric acid at a solid-liquid mass ratio of 1:15. The mixture was pretreated for 3 hours under stirring in a water bath at 70°C. The product was centrifuged and washed until the solution pH reached 7, then dried overnight at 110°C. Then, an organometallic precursor (CH3)2SnCl2 containing Sn was added, with a Sn (theoretical amount of Sn in the organometallic precursor) to SCM-15 molecular sieve mass ratio of 1:30. The mixture was thoroughly ground in a mortar to obtain a uniformly dispersed mixture.

[0119] The product was dried in an oven at 110℃ and then calcined at 550℃ for 5 hours to obtain Sn-SCM-15 molecular sieve. The UV-Vis spectrum of the sample is similar to... Figure 1 Similarly, XPS spectra and Figure 2 Similarly, this indicates that Sn successfully entered the framework of the SCM-15 molecular sieve; the pyridine desorption infrared spectrum of the sample is shown below. Figure 3Similarly, inductively coupled plasma atomic emission spectrometry (ICP) determined the Si / Ge ratio of the sample to be 8.7 (atomic ratio) and the Si / Sn ratio to be 34 (atomic ratio). The Lewis acid content calculated from the pyridine desorption infrared spectrum was 277 μmol·g. -1 The Lewis / Bronst acid ratio is 2.1, and the tin content, calculated as oxides, is 3.2 wt%.

[0120] Example 9

[0121] SCM-15 molecular sieve was synthesized according to the preparation method in Example 1 of CN109081359A. It was added to a dimethyl sulfoxide solution containing 0.02 mol / L oxalic acid at a solid-liquid mass ratio of 1:20. The mixture was pretreated for 2 hours under stirring in an 80°C water bath. The product was centrifuged and washed until the solution pH reached 7, then dried overnight at 110°C. A Zr-containing organometallic precursor, Cp2ZrCl2, was then added, with a Zr (theoretical amount of Zr in the organometallic precursor) to SCM-15 molecular sieve mass ratio of 1:30. The mixture was thoroughly ground in a mortar to obtain a uniformly dispersed mixture.

[0122] The product was dried in an oven at 110℃ and then calcined at 550℃ for 5 hours to obtain Zr-SCM-15 molecular sieve. The UV-Vis spectrum of the sample is similar to... Figure 5 Similarly, XPS spectra and Figure 6 Similarly, this indicates that Zr successfully entered the framework of the SCM-15 molecular sieve; the pyridine desorption infrared spectrum of the sample is shown below. Figure 3 Similarly, inductively coupled plasma atomic emission spectrometry (ICP) determined the Si / Ge ratio of the sample to be 7.7 (atomic ratio) and the Si / Zr ratio to be 30 (atomic ratio). The Lewis acid content calculated from the pyridine desorption infrared spectrum was 284 μmol·g. -1 The Lewis / Bronst acid ratio is 1.8, and the zirconium content, calculated as oxides, is 3.1%.

[0123] Example 10

[0124] SCM-14 molecular sieve was synthesized according to the preparation method in Example 1 of CN109081360A. It was added to a dimethyl sulfoxide solution containing 0.02 mol / L hydrochloric acid (30 wt%) at a solid-liquid mass ratio of 1:20. The mixture was pretreated in a 70°C water bath with stirring for 1 hour. The product was centrifuged and washed until the solution pH reached 7, then dried overnight at 110°C. Then, an organometallic precursor (CH3)2SnCl2 containing Sn was added, with a Sn (theoretical amount of Sn in the organometallic precursor) to SCM-14 molecular sieve mass ratio of 1:160. The mixture was thoroughly ground in a mortar to obtain a uniformly dispersed mixture.

[0125] The product was dried in an oven at 110℃ and then calcined at 550℃ for 5 hours to obtain Sn-SCM-14 molecular sieve. The UV-Vis spectrum of the sample is similar to... Figure 1 Similarly, XPS spectra and Figure 2 Similarly, this indicates that Sn successfully entered the framework of the SCM-14 molecular sieve; the pyridine desorption infrared spectrum of the sample is shown below. Figure 3 Similarly, inductively coupled plasma atomic emission spectrometry (ICP) determined the Si / Ge ratio of the sample to be 5.9 (atomic ratio) and the Si / Sn ratio to be 190 (atomic ratio). The Lewis acid content calculated from the pyridine desorption infrared spectrum was 83 μmol·g. -1 The Lewis / Bronst acid ratio is 0.4, and the tin content, calculated as oxides, is 0.6 wt%.

[0126] Examples 11-20

[0127] Using methylfuran as the substrate and n-heptane as the reaction solvent, 1.0 g of A-SCM-X molecular sieve from Examples 1-10 above, 1.0 g of methylfuran, and 30 g of n-heptane were added to a high-pressure reactor equipped with a stirrer, and the reactor was purged with 4.0 MPa of dilute ethylene (15(v)%, the remainder being nitrogen). The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 260 °C for 24 h. The conversion rate of methylfuran and the selectivity of the target product toluene were analyzed, as shown in Table 1.

[0128] Table 1. Catalyst evaluation results for Examples 1-10

[0129]

[0130]

[0131] If the data in the table differs from the example, the example shall prevail. The following are consistent.

[0132] Example 21

[0133] In this embodiment, n-heptane was used as the reaction solvent, with a mass ratio of n-heptane to methylfuran of 20 and a mass ratio of methylfuran to catalyst of 0.8. The reaction temperature was 240°C, and the reaction time was 20 h. 1.0 g of the Sn-SCM-14 molecular sieve from Example 1, 0.8 g of methylfuran, and 16 g of n-heptane were added to a high-pressure reactor equipped with a stirrer, and the reactor was purged with 2.0 MPa of dilute ethylene (15% (v)%, the remainder being nitrogen). The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 240°C for 20 h. Gas phase analysis of the reaction liquid showed a methylfuran conversion of 91% and a toluene selectivity of 94%.

[0134] Example 22

[0135] In this embodiment, n-heptane was used as the reaction solvent, with a mass ratio of n-heptane to methylfuran of 20 and a mass ratio of methylfuran to catalyst of 2.0. The reaction temperature was 260°C, and the reaction time was 30 h. 1.0 g of the Sn-SCM-14 molecular sieve from Example 1, 2.0 g of methylfuran, and 40 g of n-heptane were added to a high-pressure reactor equipped with a stirrer, and 5.0 MPa of dilute ethylene (15(v)%, the remainder being nitrogen) was introduced. The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 260°C for 30 h. Gas phase analysis of the reaction liquid showed a methylfuran conversion of 87% and a toluene selectivity of 96%.

[0136] Example 23

[0137] In this embodiment, n-octane was used as the reaction solvent, with a n-octane to methylfuran mass ratio of 30 and a methylfuran to catalyst mass ratio of 1.0. The reaction temperature was 250°C, and the reaction time was 18 hours. 1.0 g of the Sn-SCM-14 molecular sieve from Example 1, 1.0 g of methylfuran, and 30 g of n-octane were added to a high-pressure reactor equipped with a stirrer, and 4.0 MPa of dilute ethylene (15% (v)%, the remainder being nitrogen) was introduced. The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 250°C for 18 hours. Gas phase analysis of the reaction liquid showed a methylfuran conversion rate of 89% and a toluene selectivity of 94%.

[0138] Example 24

[0139] In this embodiment, n-octane was used as the reaction solvent, with a n-octane to methylfuran mass ratio of 40 and a methylfuran to catalyst mass ratio of 1.2. The reaction temperature was 240℃, and the reaction time was 25 h. 1.0 g of the Sn-SCM-14 molecular sieve from Example 1, 1.2 g of methylfuran, and 48 g of n-octane were added to a high-pressure reactor equipped with a stirrer, and the reactor was purged with 3.0 MPa of dilute ethylene (15(v)%, the remainder being nitrogen). The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 240℃ for 25 h. Gas phase analysis of the reaction liquid showed a methylfuran conversion of 86% and a toluene selectivity of 95%.

[0140] Example 25

[0141] In this embodiment, tetrahydrofuran was used as the reaction solvent, with a tetrahydrofuran to methylfuran mass ratio of 20 and a methylfuran to catalyst mass ratio of 2. The reaction temperature was 260°C, and the reaction time was 24 h. 1.0 g of the Sn-SCM-14 molecular sieve from Example 1, 2.0 g of methylfuran, and 40 g of tetrahydrofuran were added to a high-pressure reactor equipped with a stirrer, and the reactor was purged with 3.0 MPa of dilute ethylene (15(v)%, the remainder being nitrogen). The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 260°C for 24 h. Gas phase analysis of the reaction liquid showed a methylfuran conversion of 90% and a toluene selectivity of 93%.

[0142] Example 26

[0143] In this embodiment, tetrahydrofuran was used as the reaction solvent, with a tetrahydrofuran to methylfuran mass ratio of 25 and a methylfuran to catalyst mass ratio of 1.5. The reaction temperature was 250°C, and the reaction time was 28 hours. 1.0 g of the Sn-SCM-14 molecular sieve from Example 1, 1.5 g of methylfuran, and 37.5 g of tetrahydrofuran were added to a high-pressure reactor equipped with a stirrer, and 2.0 MPa of dilute ethylene (15% (v)%, the remainder being nitrogen) was introduced. The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 250°C for 28 hours. Gas phase analysis of the reaction liquid showed a methylfuran conversion rate of 86% and a toluene selectivity of 94%.

[0144] Example 27

[0145] In this embodiment, methyl isobutyl ketone (MBE) was used as the reaction solvent. The mass ratio of MBE to methyl furan was 20, and the mass ratio of methyl furan to catalyst was 3. The reaction temperature was 260°C, and the reaction time was 48 hours. 1.0 g of the Sn-SCM-14 molecular sieve from Example 1, 3.0 g of methyl furan, and 60.0 g of MBE were added to a high-pressure reactor equipped with a stirrer, and the reactor was purged with 5.0 MPa of dilute ethylene (15% (v)%, the remainder being nitrogen). The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 260°C for 48 hours. Gas phase analysis of the reaction liquid showed a methyl furan conversion of 85% and a toluene selectivity of 95%.

[0146] Example 28

[0147] In this embodiment, methyl isobutyl ketone (MBE) was used as the reaction solvent. The mass ratio of MBE to methyl furan was 40, and the mass ratio of methyl furan to catalyst was 1. The reaction temperature was 250°C, and the reaction time was 20 h. 1.0 g of the Sn-SCM-14 molecular sieve from Example 1, 1.0 g of methyl furan, and 40.0 g of MBE were added to a high-pressure reactor equipped with a stirrer, and 2.0 MPa of dilute ethylene (15% (v)%, the remainder being nitrogen) was introduced. The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 250°C for 20 h. Gas phase analysis of the reaction liquid showed a methyl furan conversion rate of 89% and a toluene selectivity of 94%.

[0148] Example 29

[0149] In this embodiment, cyclohexane was used as the reaction solvent, with a cyclohexane to methylfuran mass ratio of 30 and a methylfuran to catalyst mass ratio of 2. The reaction temperature was 260℃, and the reaction time was 30 h. 1.0 g of the Sn-SCM-14 molecular sieve from Example 1, 2.0 g of methylfuran, and 60.0 g of cyclohexane were added to a high-pressure reactor equipped with a stirrer, and 4.0 MPa of dilute ethylene (15(v)%, the remainder being nitrogen) was introduced. The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 260℃ for 30 h. Gas phase analysis of the reaction liquid showed a methylfuran conversion rate of 92% and a toluene selectivity of 95%.

[0150] Example 30

[0151] In this embodiment, cyclohexane was used as the reaction solvent, with a cyclohexane to methylfuran mass ratio of 30 and a methylfuran to catalyst mass ratio of 1.4. The reaction temperature was 250°C, and the reaction time was 48 h. 1.0 g of the Sn-SCM-14 molecular sieve from Example 1, 1.4 g of methylfuran, and 42.0 g of cyclohexane were added to a high-pressure reactor equipped with a stirrer, and 3.0 MPa of dilute ethylene (15(v)%, the remainder being nitrogen) was introduced. The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 250°C for 48 h. Gas phase analysis of the reaction liquid showed a methylfuran conversion of 93% and a toluene selectivity of 95%.

[0152] Example 31

[0153] In this embodiment, n-heptane was used as the reaction solvent, with a mass ratio of n-heptane to methylfuran of 20 and a mass ratio of methylfuran to catalyst of 0.25. The reaction temperature was 240°C, and the reaction time was 20 h. 3.2 g of the Sn-SCM-14 molecular sieve from Example 1, 0.8 g of methylfuran, and 16 g of n-heptane were added to a high-pressure reactor equipped with a stirrer, and the reactor was purged with 2.0 MPa of dilute ethylene (15(v)%, the remainder being nitrogen). The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 240°C for 20 h. Gas phase analysis of the reaction liquid showed a methylfuran conversion of 95% and a toluene selectivity of 90%.

[0154] To more intuitively describe the reaction conditions and results of Examples 21-31 above, the parameters and results are listed in Table 2.

[0155] Table 2 Catalytic results of Examples 21-31

[0156]

[0157]

[0158] Example 32

[0159] Using methylfuran as the substrate and n-heptane as the reaction solvent, 1.0 g of Sn-SCM-14 molecular sieve from Example 1, 1.0 g of methylfuran, and 30 g of n-heptane were added to a high-pressure reactor equipped with a stirrer, and the reactor was purged with 4.0 MPa dilute ethylene (15(v)%, the remainder being nitrogen). The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 260 °C for 24 h. The methylfuran conversion and the selectivity for the target product toluene were analyzed. The used catalyst was washed, dried, and then used in the next reaction, for a total of four cycles. The results are shown in Table 3. The results show that after four reactions, the DMF conversion remained above 86%, and the pX selectivity remained at 94%, indicating that the catalyst of this invention has good cycle stability.

[0160] Table 3. Methylfuran conversion and toluene selectivity under Sn-SCM-14 molecular sieve recycling conditions.

[0161] Number of passes Methylfuran conversion / % Toluene selectivity / % 1 90 96 2 89 96 3 88 95 4 86 94

[0162] Comparative Example 1

[0163] SCM-14 molecular sieve was synthesized according to the preparation method in Example 1 of CN109081360A, using methylfuran as the substrate and n-heptane as the reaction solvent. 1.0 g of the above-mentioned SCM-14 molecular sieve, 1.0 g of methylfuran, and 30 g of n-heptane were added to a high-pressure reactor equipped with a stirrer, and the reactor was purged with 4.0 MPa dilute ethylene (15(v)%, the remainder being nitrogen). The temperature was raised to the preset temperature using a programmed heating mantle, and then stirred magnetically. The reaction was carried out at 260 °C for 24 h. Analysis of the reaction solution showed a methylfuran conversion rate of 52% and a toluene selectivity of 83%.

[0164] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A process for the preparation of bio-based toluene from methylfuran, characterized in that, The method comprises: A-SCM-X molecular sieve, A in the A-SCM-X molecular sieve is selected from at least one of Sn, Zr and Ti, and X is 14 or 15, is used to catalyze the reaction of methylfuran with ethylene in the presence of an optional organic solvent; the A-SCM-X molecular sieve has a schematic chemical composition as shown in the formula "mSiO2·nGeO2·pAO2": wherein 1≤m / n≤30, 20≤m / p≤200, and the A component is located in the framework of the molecular sieve; the Lewis acid amount of the A-SCM-X molecular sieve is 30-500 µmol·g -1 , and the Lewis / Bronst acid ratio of the A-SCM-X molecular sieve is 0.5-10.

2. The method according to claim 1, wherein, the catalyst is A-SCM-X molecular sieve or a shaped catalyst of A-SCM-X molecular sieve; and / or the contacting reaction conditions comprise: the reaction temperature is 180-300℃; and / or the reaction time is 4-72h; and / or the reaction pressure is 1-8MPa.

3. The method according to claim 2, wherein, the catalyst is A-SCM-X molecular sieve; and / or the contacting reaction conditions comprise: the reaction temperature is 210-270℃; and / or the reaction time is 10-50h; and / or the reaction pressure is 2-5MPa.

4. The method according to any one of claims 1-3, wherein, the contacting is carried out in the presence of an organic solvent selected from one or more of n-heptane, n-octane, tetrahydrofuran, methyl isobutyl ketone and cyclohexane; and / or the catalyst is A-SCM-X molecular sieve; and / or the mass ratio of methylfuran to catalyst is 0.2-8:1; and / or the mass ratio of organic solvent to methylfuran is 10-80:1; and / or ethylene is used in the form of dilute ethylene, and dilute ethylene is charged into the reaction system, the concentration of dilute ethylene being 10v%-25v%, and the other gas of dilute ethylene being inert gas.

5. The method according to claim 4, wherein, the mass ratio of methylfuran to catalyst is 0.5-6:1; and / or the mass ratio of organic solvent to methylfuran is 20-50:

1.

6. The method according to claim 5, wherein, the mass ratio of methylfuran to catalyst is 0.8-2:

1.

7. The method according to any one of claims 1-3, wherein, the content of A component in the A-SCM-X molecular sieve is not less than 0.5wt% in terms of oxide; and / or The A-SCM-X molecular sieve has a 50-300 µmol•g -1 .

8. The method according to claim 7, wherein, the content of A component in the A-SCM-X molecular sieve is 0.8wt%-3.5wt% in terms of oxide; and / or The A-SCM-X molecular sieve has a Lewis acid amount of 83-292 µmol•g -1 .

9. The method according to claim 8, wherein, the content of A component in the A-SCM-X molecular sieve is 1.2-3.2wt% in terms of oxide.

10. The method according to any one of claims 1-3, wherein, the Lewis / Bronst acid ratio of the A-SCM-X molecular sieve is 0.6-5; and / or the A-SCM-X molecular sieve is Sn-SCM-14, Sn-SCM-15, Zr-SCM-14, Zr-SCM-15, Ti-SCM-14 or Ti-SCM-15 molecular sieve.

11. The method according to claim 10, wherein, the Lewis / Bronst acid ratio of the A-SCM-X molecular sieve is 0.6-2.

1.

12. The method of any one of claims 1-3, wherein, 2≤m / n≤10; 30≤m / p≤150.

13. The method of claim 12, wherein, 3.5≤m / n≤8.7; 30≤m / p≤96.

14. The method of any one of claims 1-3, wherein, The preparation method of the A-SCM-X molecular sieve comprises: (1) mixing and contacting SCM-X molecular sieve with acid-containing organic solution to carry out pretreatment, washing, drying and calcination to obtain a solid; (2) mixing the solid with a precursor solution containing a source of metal A, drying, and calcining.

15. The method of claim 14, wherein, the SCM-X molecular sieve is SCM-14 molecular sieve and / or SCM-15 molecular sieve; and / or the organic solvent in the acid-containing organic solution is at least one selected from the group consisting of dimethyl sulfoxide, tetrahydrofuran, 1,4-dioxane, methanol, and ethanol; and / or the acid is selected from the group consisting of organic acid and / or inorganic acid; and / or the acid concentration in the acid-containing organic solution is 0.001-1 mol / L.

16. The method of claim 15, wherein, the organic solvent is dimethyl sulfoxide; and / or the acid is at least one selected from the group consisting of oxalic acid, hydrochloric acid, sulfuric acid, nitric acid, and acetic acid; and / or the acid concentration in the acid-containing organic solution is 0.005-0.1 mol / L.

17. The method of claim 16, wherein, the acid is selected from the group consisting of hydrochloric acid.

18. The method of claim 14, wherein, the solid-liquid mass ratio of the SCM-X molecular sieve to the acid-containing organic solution is 1:10-40; and / or the precursor containing a source of metal A is at least one selected from the group consisting of organometallic complex containing A, metal salt containing A, and metal hydroxide containing A; and / or the mass ratio of A in the precursor solution containing a source of metal A to the SCM-X molecular sieve is 1:20-200.

19. The method of claim 18, wherein, the solid-liquid mass ratio of the SCM-X molecular sieve to the acid-containing organic solution is 1:15-20; and / or the mass ratio of A in the precursor solution containing a source of metal A to the SCM-X molecular sieve is 1:30-83.

20. The method of claim 14, wherein, the conditions of the pretreatment in step (1) include: the temperature is 30-100°C; and / or the time is 0.25-24 hours; and / or the calcination in step (1) and step (2) each includes: the calcination temperature is 300-650°C; and / or the calcination time is 1-12 hours; and / or the calcination atmosphere is oxygen or air.

21. The method of claim 20, wherein, the conditions of the pretreatment in step (1) include: the temperature is 35-90°C; and / or the time is 0.5-18 hours.

22. The method of claim 21, wherein, the conditions of the pretreatment in step (1) include: the temperature is 40-80°C; and / or the time is 0.75-12 hours.

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