Supported catalyst as well as preparation method and application thereof

Abstract

The invention relates to the technical field of catalyst preparation, and discloses a supported catalyst as well as a preparation method and application thereof. The catalyst comprises a carrier, and active metal and organic silicon loaded on the carrier, by taking the mass of the carrier as a reference, the content of the active metal in terms of element is 1-5wt%, the content of the organic silicon is 1-10wt%, and the particle size distribution of the active metal element is 0.5-4nm. According to the catalyst disclosed by the invention, the framework characteristic of the modified molecular sieve in the carrier is utilized, so that the active metal is dispersed, the VIII-group metal and the VIB-group metal can be anchored to promote the synergistic effect, and the atom utilization rate of the VIB-group metal and the catalytic activity of the catalyst are improved. The catalyst is especially suitable for glycerol hydrofining reaction, and the conversion rate of raw materials and the selectivity of 1, 3-propylene glycol are high.

Description

Technical Field

[0001] The present invention relates to the technical field of catalyst preparation, and in particular to a supported catalyst and a preparation method and application thereof. Background Art

[0002] Under the current background of the transformation of traditional refining and chemical industry to green and low-carbon chemical industry, the production of high value-added chemical products has become a transformation route that everyone is competing for. Shell Chemical Company of the United States first obtained a new polyester fiber material, polytrimethylene terephthalate (PTT), by polycondensation of 1,3-propylene glycol and terephthalic acid in 1995. Due to the "odd carbon effect" of 1,3-propylene glycol, the arrangement of the fibers is spiral, which makes PTT fibers have good elasticity, dyeing properties and easy processing, and belongs to high-end chemical products. With its excellent performance, the global demand for PTT fibers has increased year by year. However, due to the limited production capacity of 1,3-propylene glycol, the market has been in a state of supply exceeding demand. Compared with the disadvantage of low production capacity of biological methods, chemical methods can significantly increase the output of 1,3-propylene glycol, and the glycerol hydrogenation path has the advantages of mild conditions and simple steps, which has been a hot topic of research in recent years. However, the catalyst required in this path is expensive due to the use of precious metal Pt and low activity, and has not yet reached the level of industrial application. Improving the activity and selectivity of the catalyst is one of the effective ways to reduce the cost of the catalyst. Therefore, the development of highly active and selective catalyst technology for the hydrogenation of glycerol to produce 1,3-propylene glycol has high economic benefits.

[0003] CN108636440A discloses a molecular sieve-based catalyst loaded with Pt, X and W (X is Mo or Co), with mild reaction conditions and high generation rate of 1,3-propylene glycol. CN107096564A discloses a molecular sieve-based catalyst loaded with SPAO-34 as a carrier. x The maximum dispersion on the surface of the carrier promotes the interaction with Pt and provides a large number of B acid centers, but the low conversion rate of glycerol will lead to high product separation costs.

[0004] The document (Green Chemistry, 2017, 19, 2174-2183) reports an SBA-15 molecular sieve catalyst that is first doped with W and then loaded with Pt. In the glycerol hydrogenation reaction, the yield of 1,3-propylene glycol can reach 61.5%. However, the Pt loading of the catalyst is 3%, and the hydrothermal stability of SBA-15 is difficult to meet the continuous reaction, the catalyst deactivation phenomenon is obvious, and it is difficult to apply industrially. The document (ACS Catalyst, 2020, 10, 15217-15226) uses Beta molecular sieve as a carrier and ammonium paratungstate as a metal source Pt / W / β catalyst. When catalyzing the glycerol hydrogenation reaction, the yield of 1,3-propylene glycol can reach 38.87%. However, in this document, when cheaper sodium tungstate is used as the metal source, the conversion efficiency of the catalyst is greatly reduced, the conversion rate is only 36.6%, and the yield of 1,3-propylene glycol is reduced to 16.6%. Summary of the invention

[0005] The purpose of the present invention is to overcome the problem of poor catalyst activity and selectivity in the prior art for preparing 1,3-propylene glycol by hydrogenating glycerol, and to provide a supported hydrogenation catalyst and a preparation method and application thereof. Compared with the prior art, the activity and selectivity of the catalyst used in the reaction of preparing 1,3-propylene glycol by hydrogenating glycerol are significantly improved.

[0006] In order to achieve the above-mentioned purpose, the present invention provides a supported catalyst, including a carrier, an active metal and organosilicon supported on the carrier; based on the mass of the carrier, the content of the active metal in terms of element is 1-5wt%, the content of the organosilicon is 1-10wt%, and the particle size distribution of the active metal element is 0.5-4nm.

[0007] On the other hand, the present invention provides a method for preparing a supported catalyst, comprising: (1) introducing an active metal precursor into a carrier by an impregnation method, followed by drying and calcining to obtain a catalyst precursor; (2) impregnating the catalyst precursor in an organosilicon solution for surface modification to obtain the catalyst; wherein the amounts of the carrier, active metal precursor and organosilicon are such that in the final catalyst, based on the carrier, the active metal content as an element is 1-5wt%, and the organosilicon content is 1-10wt%; the carrier contains a modified molecular sieve and an optional heat-resistant inorganic oxide, wherein the modified molecular sieve is obtained by modifying the molecular sieve by the following method: subjecting the molecular sieve to hydrothermal synthesis modification in an alkaline solution and / or an acid solution, followed by solid-liquid separation to obtain the modified molecular sieve.

[0008] Finally, the present invention also provides the use of the catalyst provided by the present invention or the supported catalyst prepared by the method described in the present invention in the selective hydrogenation reaction of glycerol.

[0009] The supported catalyst provided by the present invention has high active metal dispersion, narrow particle size distribution and good surface properties. When used in the reaction of glycerol hydrogenation to produce 1,3-propylene glycol, the high active metal dispersion, narrow particle size distribution and good surface properties significantly improve the activity and selectivity of the catalyst during the reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is the in-situ infrared spectrum of Example 1 of the present invention;

[0011] Figure 2 is a HAADF-STEM transmission electron microscope image of Example 1 of the present invention;

[0012] Figure 3 is a particle size distribution diagram of metal elements in the catalyst of Example 1 of the present invention;

[0013] Figure 4 is the in-situ infrared spectrum of Comparative Example 1 of the present invention;

[0014] Figure 5 is a HAADF-STEM transmission electron microscope image of Comparative Example 1 of the present invention;

[0015] Figure 6 It is a particle size distribution diagram of the metal elements in the catalyst of Comparative Example 1 of the present invention. DETAILED DESCRIPTION

[0016] In order to fully disclose the present invention, the specific embodiments and preferred embodiments of the present invention will be described in detail below. It should be noted that the endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise range or value, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be considered as specifically disclosed in this article.

[0017] The first aspect of the present invention provides a supported catalyst, comprising a carrier, an active metal and organosilicon supported on the carrier; based on the mass of the carrier, the content of the active metal in terms of element is 1-5wt%, the content of organosilicon is 1-10wt%, and the particle size distribution of the active metal element is 0.5-4nm. The active metal in the catalyst can be selected according to the specific field of use. When applied to the field of hydrogenation, the active metal is a hydrogenation active metal, for example, it can be at least one of the metals of Group VIII and / or at least one of the metals of Group VIB. More preferably, the metal of Group VIII is Pt and / or Pd, and the metal of Group VIB is Mo and / or W; based on the mass of the carrier, the content of the metal of Group VIII in terms of element is 1-3wt%, and the content of the metal of Group VIB in terms of element is 0.5-2wt%.

[0018] In the present invention, the content of each element in the catalyst is measured by an X-ray fluorescence spectrometer. The specific test conditions are: (1) fully grinding the sample to be tested and sieving the sample to be tested to less than 200 mesh; (2) after sample preparation, sending the sample into the internal sample chamber of the X-ray fluorescence spectrometer; (3) calculating and obtaining the element content of the measured sample.

[0019] In the present invention, the particle size distribution of the active metal element on the catalyst refers to the particle size distribution of the active metal particles on the catalyst carrier, which characterizes the dispersion degree of the active metal particles. In the present invention, the particle size distribution is measured by transmission electron microscopy and then measured by data statistics. Specifically, (1) the catalyst sample to be tested is dispersed in an ethanol solution and ultrasonically treated for 30 minutes; (2) field emission transmission electron microscopy is performed for sample preparation and characterization; (3) HR-TEM photos are collected for particle size statistics to obtain data; (4) the particle size distribution is calculated and expressed as mean ± standard deviation to more accurately represent the particle size distribution. For the present invention, the active metal particle size distribution of the catalyst is preferably 1-4nm.

[0020] According to the present invention, the carrier preferably contains a modified molecular sieve and an optional heat-resistant inorganic oxide, and the content of the modified molecular sieve in the carrier is not less than 70wt%; the silicon-aluminum molar ratio of the modified molecular sieve is 800-2000, preferably 900-1200; the most probable pore size is preferably 3-4.5nm.

[0021] In the present invention, there is no particular limitation on the type of the heat-resistant inorganic oxide, and any heat-resistant inorganic oxide matrix conventionally defined in the art is applicable to the present invention. Preferably, the heat-resistant inorganic oxide is selected from at least one of aluminum oxide, magnesium oxide, titanium oxide and zirconium oxide.

[0022] In the present invention, there is no particular limitation on the type of the molecular sieve, and all molecular sieves conventionally defined in the art are applicable to the present invention. Preferably, the molecular sieve is a zeolite molecular sieve, and more preferably at least one of a Beta molecular sieve, a ZSM-5 molecular sieve, and a ZSM-22 molecular sieve. The advantage of adopting this preferred embodiment is that the appropriate pore size and framework crystal structure are conducive to the effective diffusion and adsorption of reactant molecules.

[0023] In the present invention, the introduction of organosilicon can balance the micro-hydrophobic properties of the catalyst surface with the hydrophilic properties required for the reactants to be adsorbed on the catalyst surface, and improve the adsorption and desorption behavior of the reaction products. The catalyst of the present invention can improve the selectivity and yield of the target product 1,3-propylene glycol when used for the selective hydrogenation reaction of glycerol. The present invention uses a relative hydrophilic parameter n to characterize the surface hydrophilicity of the catalyst. Specifically, the relative hydrophilic parameter n = hydrophilic parameter of the modified catalyst / hydrophilic parameter of the unmodified catalyst (catalyst precursor). In the present invention, it can be understood that the catalyst to which organosilicon is not introduced for surface modification is defined as a reference sample, and the hydrophilic parameter of the modified catalyst and the hydrophilic parameter of the unmodified catalyst refer to the presence of a hydroxyl peak at a wavelength of 3745nm measured by in-situ infrared characterization, which is measured by measuring its peak area.

[0024] In a preferred embodiment, the relative hydrophilic parameter n of the catalyst is 0.6-0.95, more preferably 0.7-0.95, for example, it can be 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95 and values ​​between any two sets of data. The advantage of adopting this preferred embodiment is that precise micro-hydrophobicity control can promote product desorption and inhibit secondary conversion of reaction products. The relative hydrophilic parameter n of the catalyst is 0.6-0.95. More preferably, the organosilicon content is 1-6wt%; the relative hydrophilic parameter n of the catalyst is 0.7-0.95.

[0025] In a preferred embodiment, the organosilicon surface modifier is selected from at least one organosilicon compound.

[0026] In a preferred embodiment, the silicon atom in the organosilicon compound is directly bonded to at least one alkoxy group and at least one hydrocarbon group, preferably 1-3 alkoxy groups and 1-3 hydrocarbon groups are directly bonded to the silicon atom in the organosilicon compound. The advantage of adopting this preferred embodiment is that it can ensure that the organosilicon compound is fully bonded to the catalyst surface during the dissociation process.

[0027] In a preferred embodiment, the hydrocarbon group is a heteroatom-substituted or unsubstituted aliphatic hydrocarbon group, and the heteroatom is selected from S and / or N. In the present invention, it can be understood that the heteroatom substitution refers to a mixture in which the heteroatom S and / or N unsaturated bonds are located on the top carbon atom of the hydrocarbon group.

[0028] In a preferred embodiment, the hydrocarbon group is a straight-chain aliphatic hydrocarbon group, and more preferably a straight-chain aliphatic hydrocarbon group with a carbon number of 1 to 12. The advantage of adopting this preferred embodiment is that a certain degree of hydrophobicity is ensured.

[0029] In a preferred embodiment, the alkoxy group is an alkoxy group having 1-8 carbon atoms, preferably an alkoxy group having 1-4 carbon atoms.

[0030] In a preferred embodiment, the structural formula of the organosilicon compound is as shown in formula (1);

[0031] R-(CH2)n-Si-(OR1)(OR2)(OR3) formula (1);

[0032] Wherein, n=1-10, R is an alkyl group or an amino group, and R1, R2, and R3 are each independently selected from a C1-C8 fatty alkyl group, preferably a C1-C4 straight-chain fatty alkyl group.

[0033] In the present invention, there is no particular limitation on the specific type of the organosilicon compound, as long as it can meet the performance requirements of the catalyst. Preferably, the organosilicon compound is selected from at least one of n-octyltrimethoxysilane, n-octyltriethoxysilane, n-dodecyltrimethoxysilane, hexadecyltrimethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, and trimethylethoxysilane, and is further preferably at least one of n-octyltrimethoxysilane, n-octyltriethoxysilane, methyltrimethoxysilane, dimethyldiethoxysilane, and methyltriethoxysilane.

[0034] In the present invention, by selecting organosilicon surface modifiers with different structures, the catalyst is surface modified to achieve precise control of micro-hydrophobicity, which can significantly improve the activity, stability of the catalyst and the selectivity of the target product.

[0035] The present invention also provides a method for preparing the above-mentioned supported catalyst, comprising: (1) introducing an active metal precursor into a carrier by an impregnation method, followed by drying and calcining to obtain a catalyst precursor; (2) impregnating the catalyst precursor in an organic silicon solution for surface modification to obtain the catalyst; wherein the amounts of the carrier, the active metal precursor and the organic silicon are such that in the final catalyst, based on the carrier, the active metal content as an element is 1-5wt%, and the organic silicon content is 1-10wt%; the carrier contains a modified molecular sieve and an optional heat-resistant inorganic oxide, wherein the modified molecular sieve is obtained by modifying the molecular sieve by the following method: subjecting the molecular sieve to hydrothermal synthesis modification in an alkaline solution and / or an acid solution, and then performing solid-liquid separation to obtain the modified molecular sieve.

[0036] In the preparation method described in the present invention, the selection and preference of the types and contents of active metals and organosilicon have been described in the catalyst, and will not be described again here.

[0037] By the method of the present invention, the metal elements of Group VIII and Group VIB are loaded on a carrier containing a modified molecular sieve, and the skeleton characteristics of the modified molecular sieve are utilized to give full play to the catalytic activity of the metal, promote the utilization of active hydrogen species formed after the dissociation of hydrogen by the metal elements of Group VIII, and reduce the weakening of catalytic activity caused by the annihilation of active hydrogen under aqueous conditions.

[0038] In the present invention, there is no particular limitation on the type of molecular sieve. Preferably, the molecular sieve is a zeolite molecular sieve, preferably at least one of a Beta molecular sieve, a ZSM-5 molecular sieve and a ZSM-22 molecular sieve. According to a preferred embodiment of the present invention, the silicon-aluminum molar ratio of the molecular sieve is 15-100. In the present invention, it is understood that the molar ratio here refers to the molar ratio of the molecular sieve before the modification treatment. In the present invention, the silicon-aluminum molar ratio of the modified molecular sieve and the types of the most probable pore size, the metal element of Group VIII, and the metal element of Group VIB have been described in the first aspect and will not be repeated here.

[0039] In the present invention, there is no particular limitation on the types of the Group VIII metal element and the Group VIB metal element precursor. Preferably, the Group VIII metal precursor and the Group VIB metal element precursor are each independently selected from their soluble salts or chlorides. According to a preferred embodiment of the present invention, the Group VIII metal element precursor is selected from at least one of chloroplatinic acid, platinum acetate, palladium nitrate and palladium chloride.

[0040] According to a preferred embodiment of the present invention, preferably, the VIB group metal element precursor is selected from at least one of sodium tungstate, ammonium tungstate, ammonium heptamolybdate, ammonium molybdate, ammonium phosphomolybdate, ammonium metatungstate and ethylammonium metatungstate, and is further preferably sodium tungstate. Sodium tungstate has high solubility and low price, and is a monomer of W precursor, which is conducive to the dispersion of metal W on the carrier and improves the catalytic efficiency of the catalyst.

[0041] In the present invention, there is no specific limitation on the impregnation method, and conventional impregnation methods in the art are applicable to the present invention. For example, co-impregnation, step-by-step impregnation, saturation impregnation, and supersaturation impregnation. According to a preferred embodiment of the present invention, step-by-step impregnation is adopted in the present invention. Specifically, the impregnation method comprises: firstly introducing a precursor of a metal element of Group VIB into the carrier, performing an aging treatment, and then performing a first drying and a first calcination, and then introducing a precursor of a metal element of Group VIII and performing a second drying and a second calcination.

[0042] In the present invention, the conditions for the aging treatment are selected over a wide range. Preferably, the conditions for the aging treatment include: a temperature of 60-140°C and a time of 4-24h, and more preferably a temperature of 80-120°C and a time of 4-12h. In the present invention, by adopting the aging treatment, the metal precursor solution can fully react with the carrier containing the modified molecular sieve to promote the metal to slowly interact with the modified framework of the molecular sieve.

[0043] In the present invention, the conditions for the first drying and the second drying can be selected in a wide range. Preferably, the conditions for the first drying and the second drying each independently include: a temperature of 80-120°C and a time of 2-8 hours.

[0044] In the present invention, the range of conditions for the first calcination is relatively wide. Preferably, the conditions for the first calcination include: a temperature of 450-650°C, a time of 2-8h, and further preferably, a temperature of 550-650°C, and a time of 2-4h. The range of conditions for the second calcination is relatively wide. Preferably, the conditions for the second calcination include: a temperature of 300-550°C, a time of 2-8h, and further preferably, a temperature of 350-450°C, and a time of 2-4h. By selecting the above-mentioned first calcination and second calcination, it is possible to effectively adjust the degree of oxidation of the bimetal on the carrier surface and give play to the advantage of the synergistic catalytic effect of the bimetal.

[0045] According to a preferred embodiment of the present invention, in the preparation method of the modified molecular sieve, the hydrothermal synthesis modification includes a first-stage hydrothermal synthesis modification and a second-stage hydrothermal synthesis modification; the first-stage hydrothermal synthesis modification is carried out in an alkaline solution, and the second-stage hydrothermal synthesis modification is carried out in an acid solution.

[0046] In the present invention, the "first stage" and "second stage" in the first stage hydrothermal synthesis and the second stage hydrothermal synthesis have no particular limitation on the order of operation. For example, the first stage hydrothermal synthesis modification may be performed first and then the second stage hydrothermal synthesis modification, or the second stage hydrothermal synthesis modification may be performed first and then the first stage hydrothermal synthesis modification. Preferably, the first stage hydrothermal synthesis modification is performed first and then the second stage hydrothermal synthesis modification.

[0047] According to a preferred embodiment of the present invention, the one-stage hydrothermal synthesis modification includes modifying the molecular sieve in an alkaline solution, performing solid-liquid separation, and washing and drying the obtained solid phase.

[0048] According to a preferred embodiment of the present invention, the two-stage hydrothermal synthesis modification includes modifying the solid phase obtained after the one-stage hydrothermal synthesis modification in an acid solution, performing solid-liquid separation, and washing and drying the obtained solid phase to obtain a modified molecular sieve.

[0049] Through the above-mentioned modification treatment, the special structure formed on the surface of the modified molecular sieve is conducive to the dispersion of the VIB group metal elements, improving the atomic utilization rate of the VIB group metal elements, and is conducive to the simultaneous anchoring of the VIII group metal elements and the VIB group metal elements, promoting synergistic effects and improving the catalytic activity of the catalyst.

[0050] In the present invention, the alkali is introduced in the form of an alkali solution, and the type of the alkali is not particularly limited, and the alkalis conventionally defined in the art are applicable to the present invention. Preferably, the alkali in the alkali solution is selected from at least one of potassium hydroxide, sodium hydroxide, sodium carbonate and sodium bicarbonate.

[0051] According to a preferred embodiment of the present invention, the concentration of the alkaline solution is 1-6 mol / L.

[0052] In the present invention, the conditions for the one-stage hydrothermal synthesis modification are selected in a wide range. Preferably, the conditions for the one-stage hydrothermal synthesis modification include: a temperature of 40-100°C and a time of 1-8h, and more preferably, a temperature of 50-70°C and a time of 1-4h. The advantages of adopting this preferred embodiment are mild conditions and the ability to form a uniform and rich mesoporous structure.

[0053] In the present invention, the drying conditions in the one-stage hydrothermal synthesis modification have a wide selection range. Preferably, the solid phase obtained by the one-stage hydrothermal synthesis modification is dried at a temperature of 80-140° C. for 2-8 hours.

[0054] In the present invention, the acid is introduced in the form of an acid solution, and the type of the acid is not particularly limited, and acids conventionally defined in the art are applicable to the present invention. Preferably, the acid in the acid solution is selected from organic acids and / or inorganic acids, preferably inorganic acids, and more preferably at least one of nitric acid, hydrochloric acid, boric acid and hydrofluoric acid.

[0055] According to a preferred embodiment of the present invention, the concentration of the acid solution is 12-18 mol / L.

[0056] In the present invention, the drying conditions in the two-stage hydrothermal synthesis modification have a wide selection range. Preferably, the conditions of the two-stage hydrothermal synthesis modification include: a temperature of 80-120°C and a time of 8-24h, preferably, a temperature of 90-110°C and a time of 10-20h. The advantage of adopting this preferred embodiment is that the framework aluminum element can fully react under hydrothermal conditions, promoting the shedding of the framework aluminum and the formation of hydroxyl nests.

[0057] In the present invention, the drying conditions in the two-stage hydrothermal synthesis modification have a wide selection range. Preferably, the solid phase obtained by the two-stage hydrothermal synthesis modification is dried at a temperature of 80-140° C. for 2-8 hours.

[0058] The carrier of the present invention may contain heat-resistant inorganic oxides in addition to the modified molecular sieve. The types and contents of the heat-resistant inorganic oxides have been recorded in the description of the supported catalyst. During the preparation process, the amount of the heat-resistant inorganic oxide is such that the contents of each species in the final supported catalyst meet the requirements.

[0059] In the present invention, the concentration of the organosilicon solution subjected to the surface modification treatment in step (2) is not particularly limited. Preferably, the concentration of the organosilicon surface modifier solution is 1-10% by mass, more preferably 1-6% by mass, and more preferably 1-4% by mass.

[0060] In the present invention, there is no particular limitation on the type of solvent for the organic silicon surface modifier solution. Preferably, the solvent for the organic silicon surface modifier solution is at least one selected from ethanol, isopropanol and n-propanol, and more preferably ethanol.

[0061] In a preferred embodiment, the modification treatment includes a first modification treatment and a second modification treatment. In the present invention, it can be understood that the first modification treatment is carried out in a stirring state, and the second modification treatment is carried out in a static state.

[0062] In a preferred embodiment, the first modification treatment is performed under stirring conditions.

[0063] In the present invention, the conditions for the first modification treatment are selected in a wide range. Preferably, the conditions for the first modification treatment include: a stirring speed of 300-1200 r / min, a temperature of 0-80°C, and a time of 4-36 h, and more preferably, a stirring speed of 400-800 r / min, a temperature of 15-40°C, and a time of 8-24 h.

[0064] In the present invention, the conditions for the second modification treatment can be selected in a wide range. Preferably, the conditions for the second modification treatment include: a temperature of 120-170°C for 4-36 hours, and more preferably, a temperature of 120-150°C for 4-12 hours.

[0065] In a preferred embodiment, the first modification treatment and the second modification treatment are performed under different conditions. Adopting this preferred embodiment is more conducive to the precise control of the micro-hydrophobicity of the surface.

[0066] The above modification treatment can adjust the adsorption mode of glycerol molecules and promote the formation of target products on the one hand, and can also promote the desorption of reaction products and by-products on the other hand, solving the problem of decreased catalyst activity due to competitive adsorption.

[0067] Finally, the present invention also provides a supported catalyst prepared by the above method, and the use of the catalyst of the present invention and the catalyst prepared by the method of the present invention in the selective hydrogenation reaction of glycerol.

[0068] In a preferred embodiment, the glycerol selective hydrogenation refining reaction is a glycerol selective hydrogenation reaction to produce 1,3-propylene glycol. In the present invention, the raw materials for the glycerol selective hydrogenation refining reaction are not particularly limited. Preferably, the raw material for the glycerol selective hydrogenation refining reaction is a 10-30% by mass glycerol aqueous solution. In a preferred embodiment, the glycerol selective hydrogenation refining reaction is carried out in at least one of a slurry bed reactor, a fixed bed reactor and a moving bed reactor, and is further preferably carried out in a slurry bed reactor.

[0069] In the present invention, the reaction conditions for selective hydrofining of glycerol are selected in a wide range. Preferably, the reaction conditions include: a catalyst-oil mass ratio of 0.02-0.1, a pressure of 2-4 MPa, a temperature of 150-170°C, and a time of 12-24 h. More preferably, the catalyst-oil mass ratio is 0.04-0.06, a pressure of 2-3 MPa, a temperature of 150-160°C, and a time of 15-18 h. In the present invention, the catalyst-oil mass ratio refers to the mass ratio of the catalyst mass to the mass of the glycerol aqueous solution.

[0070] The inventors of the present invention have found in the research that in the glycerol hydrogenation reaction, the glycerol molecules need to be adsorbed on the catalytic active sites, the hydrogen is adsorbed and dissociated by the noble metal, and the active hydrogen species attack the primary hydroxyl or secondary hydroxyl of the glycerol molecules by hydrogen overflow to generate the corresponding products. Based on this, by selecting a specific catalyst and adjusting the adsorption mode of the glycerol molecules on the catalyst surface, the catalytic efficiency of the catalyst and the selectivity of the target product can be effectively improved. The present invention plays the effect of dispersing the VIB group metal by utilizing the skeleton characteristics of the modified molecular sieve in the carrier, and can anchor the metal VIII group metal and the VIB group metal to promote their synergistic effect, thereby improving the atomic utilization rate of the VIB group metal and the catalytic activity of the catalyst. The active metal is loaded on the modified zeolite molecular sieve carrier, and the skeleton characteristics of the modified molecular sieve are utilized to give full play to the catalytic activity of the metal, promote the utilization of the active hydrogen species formed after the VIII group metal dissociates the hydrogen, and reduce the catalytic activity weakening caused by the annihilation of the active hydrogen under the condition of the aqueous phase. In addition, the use of the VIB group precursor with high solubility and low price is conducive to the dispersion of the VIB group metal on the carrier and improves the catalytic efficiency of the catalyst.

[0071] The present invention will be described in detail below by way of examples. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention. In the following examples, the process was carried out in a slurry bed reactor. The catalyst hydrophilicity parameter was measured by the method described above, and the relative hydrophilicity parameter was calculated by the following formula:

[0072] Relative hydrophilicity parameter n = hydrophilicity parameter of the modified catalyst / hydrophilicity parameter of the unmodified catalyst.

[0073] Example 1

[0074] A supported hydrogenation catalyst contains Pt, W, a modified molecular sieve and a surface modifier, wherein the loading amount of Pt is 2% of the mass of the support, the loading amount of W is 0.5% of the mass of the support, and the loading amount of the surface modifier is 2% of the mass of the support. The support is a modified Beta molecular sieve, and the silicon-aluminum molar ratio of the modified Beta molecular sieve is 1080. The particle size distribution of W and Pt on the catalyst is 1.7±0.4nm.

[0075] The supported hydrogenation catalyst is prepared by the following method:

[0076] (1) Beta molecular sieve (silicon-aluminum molar ratio of 25) was hydrothermally treated in a 2 mol / L sodium hydroxide solution at 60° C. for 2 h, filtered, washed and then dried;

[0077] (2) hydrothermally treating the material obtained in (1) in 16 mol / L concentrated nitric acid at 90° C. for 20 hours, filtering, washing and then drying to obtain a modified molecular sieve;

[0078] (3) immersing the modified molecular sieve obtained in (2) in a sodium tungstate solution, aging for 6 hours, drying, and calcining at 600° C. for 2 hours;

[0079] (4) immersing the intermediate product obtained in (3) in a chloroplatinic acid solution, drying it, and calcining it at 450° C. for 3 hours to obtain a catalyst precursor;

[0080] (5) The intermediate product obtained in (4) was dispersed in an ethanol solution of 3-aminopropyltrimethoxysilane having a concentration of 2 mass %, and modified by stirring at 25° C. for 12 hours, and then modified at 120° C. for 36 hours to obtain the catalyst.

[0081] Example 2

[0082] A supported hydrogenation catalyst comprises Pt, W, a modified molecular sieve and a surface modifier, wherein the loading amount of Pt is 2% of the mass of the support, the loading amount of W is 0.75% of the mass of the support, and the loading amount of the surface modifier is 2% of the mass of the support, wherein the support is a modified Beta molecular sieve, and the silicon-aluminum molar ratio of the modified Beta molecular sieve is 1080. The particle size distribution of W and Pt on the catalyst is 1.7±0.6nm.

[0083] The supported hydrogenation catalyst is prepared by the following method:

[0084] (1) Beta molecular sieve (silicon-aluminum molar ratio of 25) was hydrothermally treated in a 2 mol / L sodium hydroxide solution at 60° C. for 2 hours, filtered, washed and then dried;

[0085] (2) hydrothermally treating the material obtained in (1) in 16 mol / L concentrated nitric acid at 90° C. for 20 hours, filtering, washing and then drying to obtain a modified molecular sieve;

[0086] (3) immersing the modified molecular sieve obtained in (2) in a sodium tungstate solution, aging for 6 hours, drying, and calcining at 550° C. for 2 hours;

[0087] (4) immersing the intermediate product obtained in (3) in a chloroplatinic acid solution, drying, and calcining at 400° C. for 3 hours to obtain a catalyst precursor;

[0088] (5) The intermediate product obtained in (4) was dispersed in an ethanol solution of 3-aminopropyltrimethoxysilane having a concentration of 2 mass %, and modified by stirring at 25° C. for 12 hours, and then modified at 120° C. for 36 hours to obtain the catalyst.

[0089] Example 3

[0090] A supported hydrogenation catalyst comprises Pt, W, a modified molecular sieve and a surface modifier, wherein the loading amount of Pt is 1.5% of the mass of the support, the loading amount of W is 0.5% of the mass of the support, and the loading amount of the surface modifier is 2% of the mass of the support, wherein the support is a modified Beta molecular sieve, and the silicon-aluminum molar ratio of the modified Beta molecular sieve is 1080. The particle size distribution of W and Pt on the catalyst is 1.6±0.4nm.

[0091] The supported hydrogenation catalyst is prepared by the following method:

[0092] (1) Beta molecular sieve (silicon-aluminum molar ratio of 25) was hydrothermally treated in a 2 mol / L sodium hydroxide solution at 60° C. for 2 hours, filtered, washed and then dried;

[0093] (2) hydrothermally treating the material obtained in (1) in 14 mol / L concentrated nitric acid at 100° C. for 24 hours, filtering, washing and then drying to obtain a modified molecular sieve;

[0094] (3) immersing the modified molecular sieve obtained in (2) in a sodium tungstate solution, aging for 6 hours, drying, and calcining at 550° C. for 2 hours;

[0095] (4) immersing the intermediate product obtained in (3) in a chloroplatinic acid solution, drying, and calcining at 400° C. for 3 hours to obtain a catalyst precursor;

[0096] (5) The intermediate product obtained in (4) was dispersed in an ethanol solution of 3-aminopropyltrimethoxysilane having a concentration of 2 mass %, and modified by stirring at 25° C. for 12 hours, and then modified at 120° C. for 36 hours to obtain the catalyst.

[0097] Example 4

[0098] A supported hydrogenation catalyst comprises Pt, W, a modified molecular sieve and a surface modifier, wherein the loading amount of Pt is 2% of the mass of the support, the loading amount of W is 1% of the mass of the support, and the loading amount of the surface modifier is 2% of the mass of the support, wherein the support is a ZSM-5 molecular sieve, and the silicon-aluminum molar ratio of the modified ZSM-5 molecular sieve is 1020. The particle size distribution of W and Pt on the catalyst is 2.3±0.6nm.

[0099] The supported hydrogenation catalyst is prepared by the following method:

[0100] (1) treating a ZSM-5 molecular sieve (silicon-aluminum molar ratio of 25) hydrothermally in a 4 mol / L sodium hydroxide solution at 50° C. for 3 hours, filtering, washing, and then drying;

[0101] (2) hydrothermally treating the material obtained in (1) in 15 mol / L concentrated nitric acid at 100° C. for 12 hours, filtering, washing and then drying to obtain a modified molecular sieve;

[0102] (3) immersing the modified molecular sieve obtained in (2) in a sodium tungstate solution, aging for 6 hours, drying, and calcining at 550° C. for 3 hours;

[0103] (4) immersing the intermediate product obtained in (3) in a chloroplatinic acid solution, drying, and calcining at 400° C. for 3 hours to obtain a catalyst precursor;

[0104] (5) The intermediate product obtained in (4) was dispersed in an ethanol solution of 3-aminopropyltrimethoxysilane having a concentration of 2 mass %, and modified by stirring at 25° C. for 12 hours, and then modified at 120° C. for 36 hours to obtain the catalyst.

[0105] Example 5

[0106] A supported hydrogenation catalyst contains Pt, W, a modified molecular sieve and a surface modifier, wherein the loading amount of Pt is 2% of the mass of the support, the loading amount of W is 1% of the mass of the support, and the loading amount of the surface modifier is 4% of the mass of the support. The support is a modified Beta molecular sieve, and the silicon-aluminum molar ratio of the modified Beta molecular sieve is 1080. The particle size distribution of W and Pt on the catalyst is 1.8±0.6nm.

[0107] The supported hydrogenation catalyst is prepared by the following method:

[0108] (1) Beta molecular sieve (silicon-aluminum molar ratio of 25) was hydrothermally treated in a 2 mol / L sodium hydroxide solution at 60° C. for 2 hours, filtered, washed and then dried;

[0109] (2) hydrothermally treating the material obtained in (1) in 16 mol / L concentrated nitric acid at 90° C. for 20 hours, filtering, washing and then drying to obtain a modified molecular sieve;

[0110] (3) immersing the modified molecular sieve obtained in (2) in a sodium tungstate solution, aging for 6 hours, drying, and calcining at 550° C. for 2 hours;

[0111] (4) immersing the intermediate product obtained in (3) in a chloroplatinic acid solution, drying it, and calcining it at 350° C. for 3 hours to obtain a catalyst precursor;

[0112] (5) The intermediate product obtained in (4) was dispersed in an ethanol solution of 3-aminopropyltrimethoxysilane having a concentration of 4 mass %, and modified by stirring at 25° C. for 12 hours, and then modified at 120° C. for 36 hours to obtain the catalyst.

[0113] Example 6

[0114] A supported hydrogenation catalyst contains Pt, W, a modified molecular sieve and a surface modifier, wherein the loading amount of Pt is 2% of the mass of the support, the loading amount of W is 1% of the mass of the support, and the loading amount of the surface modifier is 6% of the mass of the support. The support is a modified Beta molecular sieve, and the silicon-aluminum molar ratio of the modified Beta molecular sieve is 1080. The particle size distribution of W and Pt on the catalyst is 1.8±0.6nm.

[0115] The supported hydrogenation catalyst is prepared by the following method:

[0116] (1) Beta molecular sieve (silicon-aluminum molar ratio of 25) was hydrothermally treated in a 2 mol / L sodium hydroxide solution at 60° C. for 2 hours, filtered, washed and then dried;

[0117] (2) hydrothermally treating the material obtained in (1) in 16 mol / L concentrated nitric acid at 90° C. for 20 h, filtering, washing and then drying to obtain a modified molecular sieve;

[0118] (3) immersing the modified molecular sieve obtained in (2) in a sodium tungstate solution, aging for 6 hours, drying, and calcining at 550° C. for 2 hours;

[0119] (4) immersing the intermediate product obtained in (3) in a chloroplatinic acid solution, drying, and calcining at 350° C. for 3 h to obtain a catalyst precursor;

[0120] (5) The intermediate product obtained in (4) was dispersed in an ethanol solution of 3-aminopropyltrimethoxysilane having a concentration of 6 mass %, and modified by stirring at 25° C. for 12 hours, and then modified at 120° C. for 36 hours to obtain the catalyst.

[0121] Example 7

[0122] A catalyst for preparing 1,3-propylene glycol by hydrogenating glycerol, the catalyst composition comprising W, Pt, and a modified molecular sieve carrier, wherein the loading amount of Pt is 2% of the carrier mass, and the loading amount of W is 0.5% of the carrier mass. The loading amount of the surface modifier is 4% of the carrier mass. The carrier is a modified ZSM-5 molecular sieve, and the silicon-aluminum molar ratio of the modified ZSM-5 molecular sieve is 1015. The particle size distribution of W and Pt on the catalyst is 2.2±0.6nm.

[0123] (1) treating a ZSM-5 molecular sieve (silicon-aluminum molar ratio of 25) hydrothermally in a 4 mol / L sodium hydroxide solution at 50° C. for 3 hours, filtering, washing, and then drying;

[0124] (2) hydrothermally treating the material obtained in (1) in 14 mol / L concentrated nitric acid at 100° C. for 12 hours, filtering, washing and then drying to obtain a modified molecular sieve;

[0125] (3) immersing the modified support obtained in (2) in a W precursor solution, aging for 4 hours, drying, and calcining at 650° C. for 2 hours;

[0126] (4) immersing the intermediate product obtained in (3) in a chloroplatinic acid solution, drying it, and calcining it at 450° C. for 3 hours to obtain a catalyst precursor;

[0127] (5) The intermediate product obtained in (4) was dispersed in an ethanol solution of dodecyltrimethoxysilane having a concentration of 4 mass %, and modified by stirring at 25° C. and 400 r / min for 12 h, and then modified at 120° C. for 36 h to obtain the catalyst.

[0128] Example 8

[0129] A catalyst for preparing 1,3-propylene glycol by hydrogenating glycerol, the catalyst composition comprising W, Pt, and a modified molecular sieve carrier, wherein the loading amount of Pt is 2% of the carrier mass, and the loading amount of W is 0.5% of the carrier mass. The loading amount of the surface modifier is 6% of the carrier mass. The carrier is a modified Beta molecular sieve, and the silicon-aluminum molar ratio of the modified Beta molecular sieve is 1015. The particle size distribution of W and Pt on the catalyst is 2.2±0.6nm.

[0130] (1) treating a ZSM-5 molecular sieve (silicon-aluminum molar ratio of 25) hydrothermally in a 2 mol / L potassium hydroxide solution at 55° C. for 3 hours, filtering, washing, and then drying;

[0131] (2) hydrothermally treating the material obtained in (1) in 14 mol / L concentrated nitric acid at 100° C. for 12 hours, filtering, washing and then drying to obtain a modified molecular sieve;

[0132] (3) immersing the modified support obtained in (2) in a W precursor solution, aging for 4 hours, drying, and calcining at 650° C. for 3 hours;

[0133] (4) immersing the intermediate product obtained in (3) in a chloroplatinic acid solution, drying, and calcining at 450° C. for 4 hours to obtain a catalyst precursor;

[0134] (5) The intermediate product obtained in (4) was dispersed in an ethanol solution of dodecyltrimethoxysilane having a concentration of 6 mass %, and modified by stirring at 25° C. and 400 r / min for 12 h, and then modified at 120° C. for 36 h to obtain the catalyst.

[0135] Comparative Example 1

[0136] A catalyst for preparing 1,3-propylene glycol by hydrogenating glycerol, the catalyst composition comprising W, Pt, and a modified molecular sieve carrier, wherein the loading amount of Pt is 2% of the carrier mass, and the loading amount of W is 0.5% of the carrier mass. The carrier is a Beta molecular sieve. The particle size distribution of W and Pt on the catalyst is 2.6±1.9nm. Since no surface modification is involved, the relative hydrophilic parameter is 1.

[0137] (1) unmodified Beta molecular sieve (silicon to aluminum molar ratio of 25) was immersed in a W precursor solution, aged for 6 hours, dried and calcined at 600°C for 2 hours;

[0138] (2) The intermediate product obtained in (1) is immersed in a chloroplatinic acid solution, dried, and calcined at 450° C. for 3 hours to obtain the catalyst.

[0139] Comparative Example 2

[0140] A catalyst for preparing 1,3-propylene glycol by hydrogenating glycerol, the catalyst composition comprising W, Pt, and a modified molecular sieve carrier, wherein the loading amount of Pt is 0.5% of the carrier mass, and the loading amount of W is 0.5% of the carrier mass. The carrier is a Beta molecular sieve. The particle size distribution of W and Pt on the catalyst is 2.4±1.6nm. Since no surface modification is involved, the relative hydrophilic parameter is 1.

[0141] (1) unmodified Beta molecular sieve (silicon to aluminum molar ratio of 25) was immersed in a W precursor solution, aged for 6 hours, dried and calcined at 550° C. for 2 hours;

[0142] (2) The intermediate product obtained in (1) is immersed in a chloroplatinic acid solution, dried, and then calcined at 350° C. for 3 hours to obtain the catalyst.

[0143] Comparative Example 3

[0144] A catalyst for preparing 1,3-propylene glycol by hydrogenating glycerol, the catalyst composition comprising W, Pt, and a modified molecular sieve carrier, wherein the loading amount of Pt is 2% of the carrier mass, and the loading amount of W is 0.5% of the carrier mass. The carrier is a modified Beta molecular sieve, and the silicon-aluminum molar ratio of the modified Beta molecular sieve is 1080. The particle size distribution of W and Pt on the catalyst is 1.7±0.6nm. Since no surface modification is involved, the relative hydrophilic parameter is 1.

[0145] (1) Beta molecular sieve (silicon-aluminum molar ratio of 25) was hydrothermally treated in a 2 mol / L sodium hydroxide solution at 60°C for 2 h, filtered, washed, and then dried at 100°C for 4 h;

[0146] (2) hydrothermally treating the material obtained in (1) in 16 mol / L concentrated nitric acid at 90° C. for 20 h, filtering, washing, and then drying at 100° C. for 4 h to obtain a modified molecular sieve;

[0147] (3) immersing the modified molecular sieve obtained in (2) in a sodium tungstate solution, aging for 6 hours, drying, and calcining at 550° C. for 2 hours;

[0148] (4) The intermediate product obtained in (3) is immersed in a chloroplatinic acid solution, dried, and then calcined at 350° C. for 2 hours to obtain the catalyst.

[0149] Comparative Example 4

[0150] A catalyst for preparing 1,3-propylene glycol by hydrogenation of glycerol, the catalyst composition comprising W, Pt, and a modified molecular sieve carrier, wherein the loading amount of Pt is 2% of the carrier mass, and the loading amount of W is 1% of the carrier mass. The carrier is a Beta molecular sieve, and the particle size distribution of W and Pt on the catalyst is 2.47±1.8nm.

[0151] (1) unmodified Beta molecular sieve (silicon to aluminum molar ratio of 25) was immersed in a W precursor solution, aged for 6 hours, dried and calcined at 550° C. for 2 hours;

[0152] (2) immersing the intermediate product obtained in (1) in a chloroplatinic acid solution, drying it, and then calcining it at 350° C. for 3 hours;

[0153] (3) The intermediate product obtained in (2) was dispersed in an ethanol solution of n-dodecyltrimethoxysilane having a concentration of 4 mass %, and modified by stirring at 25° C. and 400 r / min for 12 h, and then modified at 120° C. for 36 h to obtain the catalyst.

[0154] The catalysts prepared in Examples 1 to 8 and Comparative Examples 1 to 4 were used in the reaction of hydrogenating glycerol to produce 1,3-propylene glycol under the following reaction conditions: 0.2 g of the catalyst was weighed and placed in a high-pressure reactor, a glycerol aqueous solution with a mass concentration of 10% was added, and the reaction was carried out at a reaction temperature of 160° C. and a hydrogen pressure of 2.6 MPa for 16 hours. After the reaction was completed, the sample was cooled to room temperature, and a sample was taken for gas chromatography quantitative analysis, and calculated according to the following formula.

[0155] Glycerol conversion rate (%) = (molar amount of glycerol before reaction - molar amount of glycerol after reaction) / molar amount of glycerol before reaction × 100%

[0156] 1,3-propylene glycol selectivity (%) = molar amount of 1,3-propylene glycol / total molar amount of generated carbon substances

[0157] ×100%.

[0158] Table 1 Reaction evaluation results of Examples 1-8 and Comparative Examples 1-4

[0159]

[0160] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0161] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

[0162] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A supported catalyst, comprising a carrier, an active metal supported on the carrier and organosilicon; based on the mass of the carrier, the content of the active metal in terms of element is 1-5wt%, the content of the organosilicon is 1-10wt%, and the particle size distribution of the active metal element is 0.5-4nm.

2. The catalyst according to claim 1, wherein The active metal is at least one of the metals of Group VIII and / or at least one of the metals of Group VIB; the particle size distribution of the active metal is 1-4 nm; and the relative hydrophilic parameter n of the catalyst is 0.6-0.

95.

3. The catalyst according to claim 2, wherein The Group VIII metal is Pt and / or Pd, and the Group VIB metal is Mo and / or W; based on the mass of the carrier, the content of the Group VIII metal as an element is 1-3wt%, the content of the Group VIB metal as an element is 0.5-2wt%, and the content of the organosilicon is 1-6wt%; the relative hydrophilic parameter n of the catalyst is 0.7-0.

95.

4. The catalyst according to claim 1, wherein the carrier contains a modified molecular sieve and an optional heat-resistant inorganic oxide, and the content of the modified molecular sieve in the carrier is not less than 70wt%; the silicon-aluminum molar ratio of the modified molecular sieve is 800-2000, and the most probable pore size is 3-4.5nm.

5. The catalyst according to claim 4, wherein the modified molecular sieve is at least one of Beta molecular sieve, Y-type molecular sieve, ZSM-5 molecular sieve and ZSM-22 molecular sieve, the heat-resistant inorganic oxide is at least one of aluminum oxide, magnesium oxide, titanium oxide and zirconium oxide, and the silicon-aluminum molar ratio of the modified molecular sieve is 900-1200.

6. The catalyst according to any one of claims 1 to 5, wherein The organosilicon is selected from at least one of organosilicon compounds, wherein the silicon atom in the organosilicon compound is directly bonded to at least one alkoxy group and at least one hydrocarbon group, and preferably the silicon atom in the organosilicon compound is directly bonded to 1-3 alkoxy groups and 1-3 hydrocarbon groups; Preferably, when the organosilicon compound has two or more alkoxy groups, the alkoxy groups are the same or different alkoxy groups; Preferably, when the organosilicon compound has two or more hydrocarbon groups, the hydrocarbon groups are the same or different hydrocarbon groups.

7. The catalyst according to claim 6, wherein The hydrocarbon group is a heteroatom-substituted or unsubstituted aliphatic hydrocarbon group, wherein the heteroatom is selected from S and / or N; The hydrocarbon group is preferably a straight-chain aliphatic hydrocarbon group, and more preferably a straight-chain aliphatic hydrocarbon group having 1 to 12 carbon atoms; The alkoxy group is an alkoxy group having 1 to 8 carbon atoms, preferably an alkoxy group having 1 to 4 carbon atoms; Preferably, the structural formula of the organosilicon compound is as shown in formula (1); R-(CH2)n-Si-(OR1)(OR2)(OR3) formula (1); Wherein, n=1-10, R is an alkyl group or an amino group, and R1, R2, and R3 are each independently selected from a C1-C8 fatty alkyl group, preferably a C1-C4 straight-chain fatty alkyl group; Further preferably, the organosilicon compound is selected from at least one of n-octyltrimethoxysilane, n-octyltriethoxysilane, n-dodecyltrimethoxysilane, hexadecyltrimethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, 3-aminopropyltrimethoxysilane and 3-aminopropyltriethoxysilane.

8. A method for preparing a supported catalyst, comprising: (1) introducing an active metal precursor into a support by an impregnation method, followed by drying and calcining to obtain a catalyst precursor; (2) immersing the catalyst precursor in an organosilicon solution for surface modification to obtain the catalyst; The amounts of the carrier, active metal precursor and organosilicon are such that in the final catalyst, based on the carrier, the active metal content in terms of element is 1-5wt%, and the organosilicon content is 1-10wt%; the carrier contains a modified molecular sieve and an optional heat-resistant inorganic oxide, and the modified molecular sieve is obtained by modifying the molecular sieve by the following method: subjecting the molecular sieve to hydrothermal synthesis modification in an alkaline solution and / or an acid solution, and then performing solid-liquid separation to obtain the modified molecular sieve.

9. The method according to claim 8, wherein: The hydrothermal synthesis modification includes one-stage hydrothermal synthesis modification and two-stage hydrothermal synthesis modification; the one-stage hydrothermal synthesis modification is carried out in an alkaline solution, and the two-stage hydrothermal synthesis modification is carried out in an acid solution; Preferably, the one-stage hydrothermal synthesis modification includes modifying the molecular sieve in an alkaline solution, separating the solid and the liquid, and washing and drying the obtained solid phase; the two-stage hydrothermal synthesis modification includes modifying the solid phase obtained after the one-stage hydrothermal synthesis modification in an acid solution, separating the solid and the liquid, and washing and drying the obtained solid phase to obtain the modified molecular sieve.

10. The method according to claim 8, wherein: The alkali in the alkaline solution is selected from at least one of potassium hydroxide, sodium hydroxide, sodium carbonate and sodium bicarbonate; the concentration of the alkaline solution is 1-6 mol / L; The conditions of the one-stage hydrothermal synthesis modification include: temperature of 40-100°C, time of 1-8h, preferably, temperature of 50-70°C, time of 1-4h; the temperature of drying the solid phase obtained by the one-stage hydrothermal synthesis modification is 80-140°C, time of 2-8h.

11. The method according to claim 8, wherein: The acid in the acid solution is selected from organic acid and / or inorganic acid, preferably inorganic acid, and more preferably at least one of nitric acid, hydrochloric acid and boric acid; the concentration of the acid solution is 12-18 mol / L; The conditions of the two-stage hydrothermal synthesis modification include: temperature of 80-120°C, time of 8-24h, preferably, temperature of 90-110°C, time of 10-20h; the temperature of drying the solid phase obtained by the two-stage hydrothermal synthesis modification is 80-140°C, time of 2-8h.

12. The method according to claim 8, wherein: The active metal is at least one of the Group VIII metals and at least one of the Group VIB metals; The impregnation method comprises: firstly introducing a precursor of a metal element of Group VIB into a carrier, performing an aging treatment, then performing a first drying and a first calcination, and then introducing a precursor of a metal element of Group VIII and performing a second drying and a second calcination; The aging treatment conditions include: temperature of 60-140°C, time of 4-24h, preferably temperature of 80-120°C, time of 4-12h; The conditions of the first drying and the second drying each independently include: a temperature of 80-120° C. and a time of 2-8 h; The first calcination conditions include: temperature of 450-650°C, time of 2-8h, preferably, temperature of 550-650°C, time of 2-4h; the second calcination conditions include: temperature of 300-550°C, time of 2-8h, preferably, temperature of 350-450°C, time of 2-4h.

13. The method according to claim 8, wherein: The concentration of the organosilicon solution is 1-10% by mass, preferably 1-6% by mass; the solvent of the organosilicon solution is selected from at least one of ethanol, isopropanol and n-propanol; Preferably, the surface modification treatment includes a first surface modification treatment and a second surface modification treatment; The first surface modification treatment is carried out under stirring conditions, and the treatment conditions include: stirring speed of 300-1200 r / min, temperature of 0-80°C, time of 4-36h, preferably, stirring speed of 400-800 r / min, temperature of 15-40°C, time of 8-24h; The conditions of the second surface modification treatment include: temperature of 120-170° C., time of 4-36 h, preferably, temperature of 120-150° C., time of 12-24 h.

14. The method according to claim 8, wherein: The Group VIII metal is Pt and / or Pd, and the Group VIB metal is Mo and / or W. The active metal and organosilicon are used in such amounts that, based on the mass of the carrier, the content of the Group VIII metal as an element is 1-3wt%, the content of the Group VIB metal as an element is 0.5-2wt%, and the content of the organosilicon is 1-6wt%.

15. A supported catalyst prepared by the method according to any one of claims 8 to 14.

16. Use of the supported catalyst according to any one of claims 1 to 7 and 15 in the selective hydrogenation reaction of glycerol.

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