CN108654610B - Preparation method of noble metal supported catalyst, catalyst and naphthenic hydrocarbon hydrogenolysis ring-opening method - Google Patents

Abstract

The invention discloses a preparation method of a noble metal supported catalyst, a catalyst obtained by the method and a method for hydrogenolysis and ring opening of cycloalkane. The preparation method comprises: (1) preparing a first compound containing a noble metal element of Group VIII Component, the second component containing alkali metal and/or alkaline earth metal element compound and the mixed solution containing the third component of VIB and/or VIIB group metal element compound, react under certain conditions to obtain colloidal solution; (2 ) dispersing the carrier in the solvent to obtain a carrier-containing suspension; (3) mixing the colloidal solution of step (1) with the suspension of step (2), and then drying and optionally calcining to obtain the Precious metal supported catalysts. Compared with the catalyst with the same precious metal content prepared in the prior art, the precious metal supported catalyst of the present invention has significantly higher catalytic activity and selectivity for the hydrogenolysis and ring-opening of naphthene when it is used for the hydrogenolysis and ring-opening of naphthene.

Description

A kind of preparation method of precious metal supported catalyst and catalyst and naphthenic hydrocarbon hydrogenolysis ring-opening method

technical field

The invention relates to a precious metal supported catalyst, a preparation method and application, and a method for catalyzing the hydrogenolysis and ring-opening of naphthene by using the catalyst.

Background technique

With the development of the world economy, the demand for diesel oil is increasing day by day. Straight-run diesel alone cannot meet this demand, which requires the transfer of secondary processed diesel, such as catalytic cracked diesel and coker diesel. However, secondary processed diesel oil contains a large amount of sulfur, nitrogen and aromatics. Currently, sulfur and nitrogen can be removed with traditional sulfide catalysts. The technical difficulty is the conversion of aromatics. High aromatics content in diesel not only reduces oil quality, but also increases particulate emissions in diesel combustion exhaust. Usually n- or short-side chain alkanes have the highest cetane number, with long side-chain naphthenes and aromatics have higher cetane numbers, and with short or no side-chain naphthenes and aromatics cetane number lowest value. Therefore, the process of aromatics hydrosaturation is limited to improve the cetane number of diesel, while the ring-opening reaction is promising to improve the cetane number of diesel. With the increasingly stringent environmental regulations on clean energy, the dearomatization of diesel fuel has become the focus of research. Therefore, realizing the highly selective ring-opening reaction of naphthenes is of great significance for improving diesel quality.

The ring-opening reaction of cycloalkanes can proceed through the following three mechanisms: radical reaction mechanism, carbanion mechanism and hydrogenolysis mechanism (Journal of Catalysis, 2002, 210, 137-148). In contrast, the metal-catalyzed hydrogenolysis mechanism has higher activity and selectivity for the selective ring-opening reaction of cycloalkanes, mainly because the ring-opening reaction is easier than the side-chain scission reaction due to the intra-ring tension of the cycloalkane molecule.

WO/2002/007881 discloses a catalyst and process for ring-opening of naphthenic hydrocarbons, the ring-opening reaction is achieved by using an iridium catalyst supported by a composite carrier of alumina and acidic silica-alumina molecular sieve. Moreover, the catalyst was calcined and regenerated by exposure to oxygen atmosphere at 250 °C, and its ring-opening activity was not significantly deactivated.

CN200480043382.0 discloses a catalyst and a method for ring-opening cycloalkane using the catalyst. The catalyst comprises a Group VIII metal component, a molecular sieve, a refractory inorganic oxide, and an optional modifier component. Molecular sieves include MAPSO, SAPO, UZM-8 and UZM-15, Group VIII metals include platinum, palladium and rhodium, and inorganic oxides are preferably alumina.

CN200910013536.6 discloses a naphthenic hydrocarbon hydroconversion catalyst and its preparation method and application. The catalyst includes a carrier and an active metal Pt, the carrier is composed of a hydrogen-type Y-Beta composite molecular sieve and an inorganic refractory oxide, the hydrogen-type Y-Beta composite molecular sieve content in the catalyst carrier is 10wt% to 90wt%, and the active metal Pt content in the catalyst It is 0.05% to 0.6%. The catalyst is prepared by the impregnation method, and the obtained catalyst can be used for the hydroconversion of various naphthenic hydrocarbon-containing raw materials.

CN201110102568.0 discloses a selective ring-opening reaction process for aromatic hydrocarbons. The reaction is carried out in two reactors connected in series; the material enters the first reactor for deep desulfurization and denitrification, and is desulfurized through a H ₂ S and NH ₃ separation device. and nitrogen, when the S content in the material is lower than 50ppm and the N content is lower than 10ppm, the material enters the second reactor for selective ring-opening reaction, the reactor has two reaction beds, in the first reaction bed Hydrogenation saturated isomerization reaction is carried out, and the second reaction bed is subjected to selective ring-opening reaction; the first reactor selects metal sulfide catalyst; the first bed of the second reactor is filled with precious metal/molecular sieve-alumina catalyst .

The alcohol thermal reduction process uses alcohol (usually polyol) as reducing agent and solvent, and mostly does not use stabilizer. The prepared catalyst has high particle dispersion, uniform and controllable particle size distribution, low cost and simple operation. Wang reported a method for the preparation of stable single-metal nanoparticles such as Pt, Rh, Ru in organic medium by alcohol thermal reduction method without using stabilizers (Chemistry of Materials, 2000, 12(6): 1622- 1627).

However, there is still much room for improvement and improvement in the ring-opening activity and selectivity of the catalysts disclosed above in the hydrogenolysis of naphthenic hydrocarbons. The noble metal supported catalysts disclosed above for the hydrogenolysis of cycloalkanes are basically obtained by conventional impregnation or co-impregnation. There are few reports in the field of catalysts suitable for ring-opening hydrogenolysis of naphthenes.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a preparation method of a precious metal supported catalyst, a catalyst obtained by the method and application thereof, and also to provide a method for catalyzing the hydrogenolysis ring-opening reaction of naphthene.

The invention provides a preparation method of a precious metal supported catalyst, comprising the following steps:

(1) Formulating a first component containing a compound containing a Group VIII noble metal element, a second component containing a compound containing an alkali metal and/or an alkaline earth metal element, and a third component containing a compound containing a Group VIB and/or VIIB metal element Mix the solution and react at 50-200°C for 0.5-24 hours to obtain a colloidal solution;

(2) dispersing the carrier in the solvent to obtain a carrier-containing suspension;

(3) Mixing the colloidal solution of step (1) with the suspension of step (2), and then drying and optionally calcining to obtain the precious metal-supported catalyst.

The present invention also provides the noble metal supported catalyst prepared by the above method and its application in catalyzing the hydrogenolysis ring-opening reaction of naphthene.

The present invention further provides a method for ring-opening by hydrogenolysis of naphthene, which comprises contacting a raw material containing naphthene and hydrogen with a catalyst under the conditions of catalytic ring-opening by hydrogenolysis of naphthene, wherein the catalyst is the above-mentioned noble metal supported catalyst.

Compared with the catalyst with the same noble metal content prepared in the prior art, the noble metal supported catalyst of the present invention has significantly higher catalytic ring-opening activity for the hydrogenolysis of naphthene, and simultaneously has a lower cracking rate. Other features and advantages of the present invention will be described in detail in the detailed description that follows.

Description of drawings:

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the specification, and together with the following specific embodiments, are used to explain the present invention, but do not constitute a limitation to the present invention. In the attached image:

Fig. 1 is the X-ray photoelectron spectrogram of Ir 4f of the catalyst R1 prepared in Example 1 of the present invention and the comparative catalyst D1 prepared in Comparative Example 1;

FIG. 2 is an X-ray photoelectron spectrogram of Re 4f of the catalyst R1 prepared in Example 1 of the present invention and the comparative catalyst D1 prepared in Comparative Example 1. FIG.

Detailed ways

Specific embodiments of the present invention will be described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, but not to limit the present invention.

The invention provides a preparation method of a precious metal supported catalyst, comprising the following steps:

(1) Prepare a mixed solution containing the first component containing the compound of the Group VIII noble metal element, the second component containing the compound containing the alkali metal or alkaline earth metal element, and the third component containing the compound of the Group VIB and/or VIIB metal element , react at 50-200°C for 0.5-24 hours, preferably at 100-180°C for 2-10 hours to obtain a colloidal solution;

(2) dispersing the carrier in the solvent to obtain a carrier-containing suspension;

(3) Mixing the colloidal solution of step (1) with the suspension of step (2), and then drying and optionally calcining to obtain the precious metal-supported catalyst.

Wherein, the three components of the step (1) can be prepared separately and then mixed according to their respective properties such as solubility and compatibility, or they can be directly prepared in the same solution; for example, a solution containing the first component can be prepared separately. , and a solution containing the second component and the third component at the same time, and then mixing the two; , then mix the two.

After the solution containing the three components of the step (1) is mixed, the reaction is preferably carried out under an inert atmosphere and/or a reducing atmosphere, and the inert atmosphere and/or the reducing atmosphere can be nitrogen, argon, helium, and hydrogen. and their mixtures.

Preferably, in step (1), the Group VIII noble metal element is at least one selected from Ir, Rh and Ru, and the Group VIII noble metal element-containing compound is selected from H ₂ IrCl ₆ , (NH _{4 )} ) ₂ IrCl ₆ , IrCl ₃ , (NH ₄ ) ₃ IrCl ₆ , RhCl ₃ , (NH ₄ ) ₃ RhCl ₆ , RhPO ₄ , Rh ₂ (SO ₄ ) ₃ , RuCl ₃ , (NH ₄ ) ₃ RuCl ₆ , Ru At least one of (CH ₃ COO) ₃ and Ru(NO)(NO ₃ ) ₃ ; further preferably, the Group VIII noble metal element is Ir, and the compound containing the Group VIII noble metal element is selected from H ₂ At least one of IrCl ₆ , (NH ₄ ) ₂ IrCl ₆ , IrCl ₃ , (NH ₄ ) ₃ IrCl ₆ .

In step (1), the alkali metal or alkaline earth metal element is preferably selected from at least one of Li, Na, K, Rb and Ba, the compound containing the alkali metal or alkaline earth metal element is preferably hydroxide, and the first The VIB and/or VIIB group metal element is preferably at least one of Mo, W, Re, and Mn.

Preferably, the solvent used for preparing the solution of the three components in step (1) and the solvent in step (2) may be the same solvent or different solvents, and the two may be independently selected from Alcohol or mixture of alcohol and water, the alcohol is at least one selected from monohydric alcohol, dihydric alcohol and trihydric alcohol having 1-6 carbon atoms, and the content of alcohol in the solvent is 40-100% by weight ; Further preferably, the alcohol is at least one of ethanol, ethylene glycol, 1,2-propanediol, 1,3-propanediol, and glycerol, and the content of the alcohol in the solvent is 70-100% by weight.

In order to have better final catalyst performance, when preparing the colloidal solution, preferably, the amount of each component in step (1) is such that, based on the weight of the colloidal solution, the content of the first component in terms of Group VIII noble metal elements is 1-200 g/l, the content of the second component in terms of alkali metal and/or alkaline earth metal elements is 1-500 g/l, and the content of the third component in terms of metal elements of Group VIB and/or VIIB is 1 -500 g/l.

The carrier of the step (2) is not particularly limited, preferably, it can be one selected from the group consisting of aluminum oxide, silicon oxide, titanium oxide, magnesium oxide, zirconium oxide, thorium oxide, beryllium oxide, clay, molecular sieve, and activated carbon. variety.

The method of dispersing the carrier in the solvent in the step (2) is not particularly limited, and can be various methods known to those skilled in the art; for example, electromagnetic stirring dispersion and ultrasonic dispersion can be used.

In the catalyst finally obtained, preferably, the amount of each component in step (1) and step (2) is such that the content of each component in the catalyst in terms of element is as follows: the content of noble metal element is 0.2-15% by weight, the VIB and / or VIIB group metal element content is 0.2-15% by weight, alkali metal and/or alkaline earth metal content is 0-2%, and the rest are carriers, satisfying the total amount of 100% by weight. Further preferably, the content of noble metal elements is 0.5-10% by weight, the content of VIB and/or VIIB metal elements is 0.5-10% by weight, the content of alkali metals and/or alkaline earth metals is 0-1%, and the rest are carriers.

After mixing the colloidal solution of step (1) and the suspension of step (2), it can be separated first and then dried, or it can be directly dried. Generally, when the solid content is low, such as below 50%, it is preferred to separate and then dry, and when the solid content is high, such as above 50%, it is directly dried. The separation method and drying method of the step (3) are not particularly limited, and can be various methods known to those skilled in the art; Oven drying and vacuum drying in air atmosphere. The drying conditions are also not particularly limited, and preferred drying conditions include: temperature 40-200° C., time 0.1-24 hours. The above-mentioned dried product can also be calcined or not calcined according to different requirements, and the calcination conditions are not particularly limited. Preferably, calcination can be performed at 200-600° C. for 0.1-24 hours.

The present invention also provides the noble metal supported catalyst prepared by the above method. Under preferred conditions, based on the element and based on the total amount of catalyst, the content of noble metal is 0.2-15% by weight, the content of element VIB and/or VIIB is 0.2-15% by weight, and the content of alkali metal and/or alkaline earth metal is 0 -2% by weight, the rest are carriers; further preferably, the content of precious metals is 0.5-10% by weight, the content of VIB and/or Group VIIB elements is 0.5-10% by weight, and the content of alkali metals and/or alkaline earth metals is 0-1 % by weight, and the rest are carriers.

The inventors tested the metal content of the catalyst obtained by the present invention, and the results show that the precious metal supported catalyst obtained by the method of the present invention satisfies (M ₂ /M ₁ ) _XPS /(M ₂ /M ₁ ) _XRF = 2-20, Preferably 2.5-10, more preferably 3-5, wherein M ₁ is a Group VIII noble metal element, M ₂ is a Group VIB and/or VIIB metal element, (M ₂ /M ₁ ) _XPS is X-ray photoelectron spectroscopy The weight ratio of M ₂ to M ₁ in the catalyst characterized by metal elements, (M ₂ /M ₁ ) _XRF is the weight ratio of M ₂ and M ₁ in the catalyst characterized by X-ray fluorescence spectroscopy in terms of metal elements. The X-ray photoelectron spectrum was measured using a monochromator Al Kα X-ray with an excitation light source of 150 kW, and the measurement conditions of the X-ray fluorescence spectrum included a rhodium target, a laser voltage of 50 kV and a laser current of 50 mA.

The present invention also provides the application of the above-mentioned noble metal supported catalyst in catalyzing the hydrogenolysis ring-opening reaction of naphthene.

In addition, the present invention also provides a method for catalyzing the hydrogenolysis and ring-opening reaction of naphthene, the method comprising contacting a raw material containing naphthenes and hydrogen with a catalyst under the conditions of catalyzing the hydrogenolysis and ring-opening of naphthenes, wherein the catalyst is the above-mentioned noble metal supported type catalyst. The catalyst of the present invention can be used for the hydrogenolysis ring-opening reaction of various naphthenic-containing raw materials, for example, the naphthenic-containing raw materials are naphthenic model compounds, or naphthenic-containing gasoline fractions, kerosene fractions, or diesel fractions, etc., preferably aromatic hydrocarbons The mass content is less than 15%, and the sulfur mass content is less than 30ppm.

The conditions for catalytic naphthene hydrogenolysis and ring opening can be carried out with reference to the prior art. Preferably, the temperature is 180-450°C, the pressure is 1-18MPa, the volume ratio of hydrogen to oil is 50-10000:1, and the mass space velocity is 0.1-100 hour ^-1 ; further preferably: the temperature is 220-400°C, the pressure is 2-12MPa, the volume ratio of hydrogen to oil is 50-5000:1, and the mass space velocity is 0.2-80 hours ^-1 .

The device for the contact reaction can be carried out in any reactor sufficient to allow the feedstock to react with the precious metal-supported catalyst under hydrogenation reaction conditions, such as a fixed bed reactor, a slurry bed reactor, a moving bed reactor or ebullated bed reactor.

Compared with the catalyst with the same precious metal content prepared in the prior art, the catalyst prepared by the method of the present invention has significantly higher catalytic ring-opening activity of cycloalkane hydrogenolysis and lower cracking rate at the same time. The reason may be that the preparation method of the catalyst provided by the present invention greatly improves the interaction interface between the noble metal and the species containing the VIB and/or VIIB group elements, which is beneficial to the selection of the secondary carbon-tertiary carbon bond in the cycloalkane. cleavage, thereby improving its ring-opening selectivity.

The following examples facilitate a better understanding of the present invention, but do not limit the present invention. In the following examples, the described percentages, unless otherwise specified, are the mass percentages; the catalyst composition is based on the total weight of the catalyst, the mass percentages of the hydrogenation active metal elements, and The composition is calculated according to the feeding amount; the measuring instrument of X-ray photoelectron spectroscopy is ESCALab250 instrument of Thermo Scientific Company, and the measurement conditions are: the excitation light source is a monochromator Al Kα X-ray of 150 kW, and the binding energy adopts the C 1s peak (284.8 eV ) calibration; the measuring instrument of X-ray fluorescence spectrum is Japan Rigaku Electric Industrial Co., Ltd. 3271 instrument, and the measurement conditions are: powder sample compression molding, rhodium target, laser voltage 50kV, laser current 50mA.

Example 1

This example is used to illustrate the catalyst provided by the present invention and its preparation method.

Prepare 100 ml of chloroiridic acid containing iridium 6.0 g/l and perrhenic acid containing 10.0 g/l rhenium in ethylene glycol, add it to 100 ml of potassium hydroxide containing 18.5 g/l potassium under stirring In the ethylene glycol solution, stirring was continued for 1 hour at room temperature, and the obtained reactant was refluxed at 160° C. for 4 hours under nitrogen protection to obtain about 200 ml of iridium colloid solution, which was cooled to room temperature for use.

Take 20 grams of SiO ₂ -Al ₂ O ₃ carrier (prepared according to Example 2 of CN201110139331.X, the same below), and disperse it in 50 ml of ethanol with electromagnetic stirring. Under rapid electromagnetic stirring, the above-mentioned 200 ml of iridium colloid solution was added dropwise to the above-mentioned 50 ml of carrier-dispersed ethanol, and electromagnetic stirring was continued for 2 hours. The solid was filtered under reduced pressure, washed with water for several times, and vacuum-dried at 120° C. for 12 hours to obtain an iridium-containing supported catalyst, which was stored in a desiccator for later use. The obtained catalyst is denoted as R1, and its composition, XPS and XRF characterization results are shown in Table 1, wherein the X-ray photoelectron spectrum is shown in Figures 1 and 2. The surface atomic ratio (M ₂ /M ₁ ) _XPS was obtained by converting the corresponding peak areas of the electron binding energies of Ir 4f and Re 4f. The composition is based on the total weight of the catalyst, the mass percentage content of the iridium, the third and the second component metal elements in terms of elements (the same below).

Comparative Example 1

This comparative example is used to illustrate the comparative catalyst and its preparation method.

The iridium-containing supported catalyst was prepared by co-impregnation method. Prepare 44 ml of an aqueous solution of chloroiridic acid containing 11.4 g/L of iridium and 15.9 g/L of perrhenic acid containing rhenium, and immerse the same volume into 20 g of SiO ₂ -Al ₂ O ₃ carrier, stir well at 20°C, and keep it at rest. After 4 hours, drying at 120°C, calcining at 400°C for 4 hours, hydrogen reduction at 400°C for 4 hours, and hydrogen pressure of 0.1 MPa. After reduction, it was lowered to room temperature and stored in a desiccator for later use. The obtained catalyst is denoted as D1, and its composition, XPS and XRF characterization results are shown in Table 1. The X-ray photoelectron spectra are shown in Figures 1 and 2.

Comparative Example 2

This comparative example is used to illustrate the comparative catalyst and its preparation method.

The catalyst was prepared according to the method of Example 1, except that the ethylene glycol solution used for preparing the iridium colloid solution did not contain perrhenic acid. The obtained catalyst is denoted as D2, and its composition, XPS and XRF characterization results are shown in Table 1.

Example 2

This example is used to illustrate the catalyst provided by the present invention and its preparation method.

Prepare 100 ml of chloroiridic acid containing iridium 6.0 g/l and perrhenic acid containing 15.6 g/l rhenium in ethylene glycol, and add it to 100 ml of potassium hydroxide containing 18.5 g/l potassium under stirring. In the ethylene glycol solution, stirring was continued for 1 hour at room temperature, and the obtained reactant was refluxed at 160° C. for 4 hours under nitrogen protection to obtain about 200 ml of iridium colloid solution, which was cooled to room temperature for use.

Take 20 g of SiO ₂ -Al ₂ O ₃ carrier and disperse it in 50 ml of ethanol with magnetic stirring. Under rapid electromagnetic stirring, the above-mentioned 200 ml of iridium colloid solution was added dropwise to the above-mentioned 50 ml of carrier-dispersed ethanol, and electromagnetic stirring was continued for 2 hours. The solid was filtered under reduced pressure, washed with water for several times, and vacuum-dried at 120° C. for 12 hours to obtain an iridium-containing supported catalyst, which was stored in a desiccator for later use. The obtained catalyst is denoted as R2, and its composition, XPS and XRF characterization results are shown in Table 1.

Example 3

This example is used to illustrate the catalyst provided by the present invention and its preparation method.

Prepare 100 ml of an ethylene glycol solution of iridium chloride containing 10.3 g/l iridium and add it to 100 ml of potassium hydroxide containing 3.2 g/l potassium and ammonium tungstate containing 15.6 g/l tungsten under stirring. In the ethylene glycol solution, stirring was continued for 1 hour at room temperature, and the obtained reactant was refluxed at 160° C. for 6 hours under nitrogen protection to obtain about 200 ml of iridium colloid solution, which was cooled to room temperature for use.

Take 20 g of SiO ₂ -Al ₂ O ₃ carrier and disperse it in 50 ml of ethanol with magnetic stirring. Under rapid electromagnetic stirring, the above-mentioned 200 ml of iridium colloid solution was added dropwise to the above-mentioned 50 ml of carrier-dispersed ethanol, and electromagnetic stirring was continued for 2 hours. The solid was filtered under reduced pressure, washed with water for several times, and vacuum-dried at 140° C. for 10 hours to obtain an iridium-containing supported catalyst, which was stored in a desiccator for later use. The obtained catalyst is denoted as R3, and its composition, XPS and XRF characterization results are shown in Table 1.

Example 4

This example is used to illustrate the catalyst provided by the present invention and its preparation method.

Prepare 100 ml of a solution of ruthenium chloride containing 6.0 g/l of ruthenium in 1,2-propanediol and add it to 100 ml of sodium hydroxide containing 8.4 g/l of sodium and molybdic acid containing 10.0 g/l of molybdenum under stirring In the 1,2-propanediol solution of ammonium, stirring was continued for 1 hour at room temperature, and the obtained reactant was refluxed at 160° C. for 4 hours under nitrogen protection to obtain about 200 ml of ruthenium colloidal solution, which was cooled to room temperature for use.

Take 20 grams of γ-Al ₂ O ₃ carrier (product of Changling Catalyst Factory, particle size 20-40 mesh), and disperse it in 50 ml of ethanol with electromagnetic stirring. Under rapid electromagnetic stirring, the above-mentioned 200 ml of the ruthenium colloid solution was added dropwise to the above-mentioned 50 ml of ethanol dispersed with the carrier, and the electromagnetic stirring was continued for 4 hours. The solid was filtered under reduced pressure, washed with water several times, and vacuum-dried at 140° C. for 8 hours to obtain a ruthenium-containing supported catalyst, which was stored in a desiccator for later use. The obtained catalyst is denoted as R4, and its composition, XPS and XRF characterization results are shown in Table 1.

Examples 5-8

These examples are used to illustrate the results of the catalytic hydrogenolysis ring opening of the model compound methylcyclopentane by the catalyst provided by the present invention.

Catalysts R1, R2, R3 and R4 were evaluated separately according to the following procedure.

The activity of the catalyst was evaluated on a continuous flow fixed-bed micro-reaction device. The feedstock oil was the model compound methylcyclopentane, the catalyst loading was 0.5 g, and the reaction conditions were: the pressure was 3.0 MPa, and the feedstock oil was 0.2 ml. /min, the volume ratio of hydrogen to oil is 1000, and the temperature is 260° C. After 3 hours of reaction, sampling is carried out for on-line gas chromatographic analysis. Before the start of the reaction, reduction was performed in a hydrogen atmosphere at 260° C., 3.0 MPa hydrogen pressure, and 200 ml/min flow rate for 2 hours. The reaction results are listed in Table 2.

Comparative Example 3-4

These comparative examples are used to illustrate the hydrogenolysis ring-opening activity of comparative catalysts.

Comparative catalysts D1 and D2 were evaluated according to the same method and conditions as in Example 5. The reaction results are listed in Table 2.

Table 1

Table 2

Example catalyst Conversion rate of methylcyclopentane (%) Linear alkane selectivity (%) Comparative Example 3 D1 47 46 Comparative Example 4 D2 41 37 Example 5 R1 69 52 Example 6 R2 67 53 Example 7 R3 66 50 Example 8 R4 64 49

Examples 9-12

These examples illustrate the hydrogenolysis ring-opening activity of the catalyst provided by the present invention when treating oil.

Catalysts R1, R2, R3 and R4 were evaluated separately according to the following procedure.

On a 30 ml hydrogenation unit, the catalytic cracked diesel oil after deep hydrodesulfurization and partial saturation of aromatic hydrocarbons was used as the reaction raw material (total aromatics content 9.5% by weight, sulfur content 8.1ppm, cetane number 39.2), and the extraction of the oil was carried out. Ring activity evaluation. The catalyst loading amount is 20 ml, and it is diluted to 30 ml with quartz sand, and the particle size is 20-40 mesh. Before starting the reaction, reduction was performed for 4 hours in a hydrogen atmosphere at 290° C., 6.0 MPa hydrogen pressure, and 200 ml/min flow rate. Then, under the condition of constant temperature and pressure, the activity of the catalyst was evaluated under the conditions of a liquid volume space velocity of 1.5 hours ^-1 and a hydrogen oil volume ratio of 800. After the reaction was stable for 24 hours, samples were taken to analyze the hexadecane that produced diesel. value. The evaluation results are shown in Table 3.

Comparative Examples 5-6

This comparative example is used to illustrate the ring-opening activity of the comparative catalyst when treating oil.

The comparative catalysts D1 and D2 were respectively evaluated according to the same method and conditions as in Example 9. The reaction results are listed in Table 3.

Table 3 Evaluation results of oil products treated with catalysts

Example catalyst cetane number increase Comparative Example 5 D1 9.3 Comparative Example 6 D2 8.8 9 R1 11.8 10 R2 11.1 11 R3 11.7 12 R4 10.9

The results of these examples show that the catalyst provided by the present invention has better naphthene ring-opening activity compared with the catalyst prepared by the prior art with the same precious metal content, and has a greater increase in the cetane number of diesel fuel.

The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the specific details of the above-mentioned embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention. These simple modifications All belong to the protection scope of the present invention.

In addition, it should be noted that each specific technical feature described in the above-mentioned specific implementation manner may be combined in any suitable manner under the circumstance that there is no contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

Claims (11)

1. a preparation method of a precious metal supported catalyst, comprising the steps: (1) Preparation of a mixture of a first component containing a compound containing a Group VIII noble metal, a second component containing a compound containing an alkali metal and/or an alkaline earth metal element, and a third component containing a compound containing a Group VIB and/or VIIB metal element The solution is reacted at 50~200°C for 0.5~24 hours to obtain a colloidal solution; (2) dispersing the carrier in the solvent to obtain a suspension containing the carrier; (3) mixing the colloidal solution in step (1) with the suspension in step (2), and then drying and optionally calcining to obtain the precious metal-supported catalyst; The solvent of the solution in step (1) is the same or different from the solvent in step (2), and is independently selected from alcohol or a mixture of alcohol and water, and the alcohol is a monovalent alcohol with 1-6 carbon atoms. At least one of alcohol, dihydric alcohol, and trihydric alcohol, and the content of alcohol in the solvent is 40-100% by weight; The noble metal supported catalyst satisfies (M ₂ /M ₁ ) _XPS /(M ₂ /M ₁ ) _XRF =2-20, wherein M ₁ is a noble metal element of Group VIII, and M ₂ is Group VIB and/or VIIB Metal element, (M ₂ /M ₁ ) _XPS is the weight ratio of M ₂ to M ₁ in the catalyst characterized by X-ray photoelectron spectroscopy as metal element, (M ₂ /M ₁ ) _XRF is characterized by X-ray fluorescence spectrum The weight ratio of M ₂ and M ₁ in terms of metal elements in the catalyst; the X-ray photoelectron spectrum is measured by using a monochromator Al Kα X-ray with an excitation light source of 150kW, and the measurement conditions of the X-ray fluorescence spectrum include rhodium The target, laser voltage was 50 kV and laser current was 50 mA. 2. The preparation method according to claim 1, wherein the Group VIII noble metal element is at least one selected from Ir, Rh and Ru, and the Group VIII noble metal element-containing compound is selected from H ₂ IrCl _6. (NH ₄ ) ₂ IrCl ₆ , IrCl ₃ , (NH ₄ ) ₃ IrCl ₆ , RhCl ₃ , (NH ₄ ) ₃ RhCl ₆ , RhPO ₄ , Rh ₂ (SO ₄ ) ₃ , RuCl ₃ , (NH ₄ ) ₃ At least one of RuCl ₆ , Ru(CH ₃ COO) ₃ , Ru(NO)(NO ₃ ) ₃ ; the alkali metal or alkaline earth metal element is at least one selected from Li, Na, K, Rb, and Ba One, the compound containing alkali metal and/or alkaline earth metal element is hydroxide; The VIB and/or VIIB group metal element is at least one selected from Mo, W, Re, Mn. 3. The preparation method according to claim 1, wherein the alcohol is at least one of ethanol, ethylene glycol, 1,2-propanediol, 1,3-propanediol, and glycerol, and the alcohol in the solvent The content is 70-100% by weight. 4 . The preparation method according to claim 1 , wherein the amount of each component in step (1) is such that based on the weight of the colloidal solution, the content of the first component in terms of Group VIII noble metal element is 1- 200 g/l, the content of the second component in terms of alkali metal and/or alkaline earth metal elements is 1-500 g/l, and the content of the third component in terms of metal elements of Group VIB and/or VIIB is 1-500 g/L. 5. The preparation method according to claim 1, wherein the consumption of each component in step (1) and step (2) is such that the content of each component in the final catalyst in terms of element is as follows: the content of precious metal element is 0.2-15 weight %, the VIB and/or VIIB group metal element content is 0.2-15% by weight, the alkali metal and/or alkaline earth metal content is 0-2%, and the rest are carriers. 6. The preparation method according to claim 5, wherein the amount of each component in step (1) and step (2) is such that the content of each component in the final catalyst in terms of element is as follows: the content of precious metal element is 0.5-10% by weight %, the VIB and/or VIIB group metal element content is 0.5-10% by weight, the alkali metal and/or alkaline earth metal content is 0-1%, and the rest are carriers. 7 . The preparation method according to claim 1 , wherein the drying operating conditions in step (3) include: the temperature is 40-200° C., and the time is 0.1-24 hours; the roasting in step (3) The operating conditions include: the temperature is 200-600°C, and the time is 0.1-24 hours. 8. The preparation method according to any one of claims 1-7, wherein the carrier is aluminum oxide, silicon oxide, titanium oxide, magnesium oxide, zirconium oxide, thorium oxide, beryllium oxide, clay, molecular sieve, activated carbon one or more of. 9. A noble metal supported catalyst prepared by the method of any one of claims 1-8. 10. Application of the noble metal supported catalyst of claim 9 in catalyzing the hydrogenolysis ring-opening reaction of naphthene. 11. A method for catalyzing cycloalkane hydrogenolysis and ring-opening, the method comprising contacting a raw material containing cycloalkane, hydrogen and a catalyst under the conditions of catalyzing cycloalkane hydrogenolysis and ring-opening, wherein the catalyst is the supported catalyst of claim 9 The conditions for the catalytic naphthene hydrogenolysis ring opening include a temperature of 180-450° C., a pressure of 1-18 MPa, a hydrogen-oil volume ratio of 50-10000:1, and a mass space velocity of 0.1-100 hours ^-1 .

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