Hydrodeoxygenation catalyst, preparation method thereof and method for producing cycloalkane from lignin

Abstract

The invention provides a hydrodeoxygenation catalyst, a preparation method thereof and a method for producing cycloalkane from lignin. The preparation method comprises the following steps: treating a beta-type molecular sieve with ethylenediamine tetraacetic acid and / or capryloyl hydroximic acid to obtain a first carrier precursor; treating the first carrier precursor with sodium hydroxide to obtain a second carrier precursor; treating the second carrier precursor with disodium ethylene diamine tetraacetate and / or tetrasodium diamine tetraacetate and / or sodium gluconate and / or sodium citrate to obtain a third carrier precursor; carrying out ammonium ion exchange on the third carrier precursor, and roasting in an aerobic atmosphere to obtain a catalyst carrier; mixing the catalyst carrier with a solution in which ruthenium trichloride and urea are dissolved, and standing at 115-135 DEG C for not less than 20 hours to obtain a catalyst precursor; the mass content of ruthenium is 1-20% when the mass of ruthenium and the mass of the catalyst carrier are 100%; and reducing the catalyst precursor in a hydrogen-containing oxygen-free mixed gas atmosphere to obtain the hydrodeoxygenation catalyst.

Description

Technical Field

[0001] The invention belongs to the technical field of catalysts, and in particular relates to a hydrodeoxygenation catalyst suitable for producing cycloalkanes from lignin, a method for preparing the catalyst, and a method for producing cycloalkanes from lignin using the catalyst. Background Art

[0002] The rapid development of the global economy and the rapid growth of the population have led to increasing pressure on the fossil energy supply chain. In order to relieve the pressure, it is of great significance to find a way to replace fossil fuels with renewable resources. As an important renewable resource, biomass has the characteristics of low ash content, more aromatic ring units, and continuous renewable compared with fossil fuels, and has great development prospects.

[0003] Cycloalkane oil (such as cyclohexane, methylcyclohexane, ethylcyclohexane, propylcyclohexane, etc.) has a saturated cyclic carbon chain structure, and has the characteristics of low pour point, high density, high viscosity, and no toxic side effects. Moreover, saturated side chains are usually connected to its saturated cyclic carbon chain structure, which makes cycloalkane oil have both some properties of aromatic hydrocarbons and some properties of straight-chain hydrocarbons. Cycloalkane oil has excellent solubility and low-temperature performance, and has excellent compatibility and good mutual solubility with resins and rubbers. It is also an important electrical insulation heat-conducting medium and chemical process solvent. Cycloalkane oil is widely used in synthetic transformer cooling oil, metalworking protective fluid, rubber plasticizer and rubber filling operating oil. At present, cycloalkane oil mainly comes from petroleum refining, and its reserves account for only 2.2% of the world's proven petroleum reserves, which is a scarce resource. Therefore, developing a new cycloalkane oil production route with renewable raw materials, environmental friendliness and high efficiency has become an important task for researchers.

[0004] Lignin is a natural high molecular weight three-dimensional network aromatic polymer formed in plant cells. Its amount in nature is second only to cellulose, accounting for 15%-30% of the total biomass. As a natural polymer with abundant reserves in nature and rich in aromatic ring structural units, it can produce cyclopentane oil after depolymerization and bond breaking and hydrogenation saturation treatment. Therefore, as a renewable resource, lignin is an ideal resource that can replace petroleum to produce cyclopentane oil in the future.

[0005] At present, the research on the preparation of naphthenic oil using lignin as raw material is limited and immature. For example:

[0006] CN102876349A discloses a one-pot method for preparing high-quality gasoline directly from lignin, which uses a sedimentation method to load nickel on HBEA molecular sieve to synthesize Ni / HBEA catalyst, and then uses lignin as a raw material, adds it together with non-polar organic solvent hexadecane and metal catalyst Ni / HBEA into an autoclave and fills with hydrogen for reaction, and obtains a product that does not need to be separated and can be directly used as a biofuel. This scheme has many defects: (1) a large amount of organic solvent hexadecane is required in the process of lignin conversion (77.3g of hexadecane is required to convert 4g of lignin), which greatly increases the cost; (2) the catalyst Ni / HBEA causes the organic solvent hexadecane to isomerize and hydrocracking in the process of catalyzing the conversion of lignin, resulting in a large loss of solvent and hydrogen; (3) the conversion product of lignin is difficult to separate from the solvent, and can only be used together with the organic solvent during use, thereby weakening the potential for high value-added utilization of lignin.

[0007] CN101171324A discloses a process for catalytically converting lignin into liquid biofuel, wherein the process comprises the following steps: 2 Mg(OH) 2 ) to cause the lignin material to undergo an alkali-catalyzed depolymerization reaction in water (stage I) to obtain partially depolymerized lignin, and then the catalyst CoMo / Al 2 O 3 The partially depolymerized lignin is then stabilized / partially hydrodeoxygenated (stage II) to form a partially hydrodeoxygenated product, which is then treated with a CoMo / Al2O3 solution in a refining step (stage III). 2 O 3 and CoMo / Al 2 O 3 -SiO 2 This solution has many disadvantages: (1) In order to recover the partially depolymerized phenolic lignin products, CO 2 (1) The product of stage I is neutralized with acidic substances such as hydrochloric acid, sulfuric acid, and phosphoric acid. This process leads to the loss of the base catalyst (making the base catalyst used in stage I non-renewable) and the loss of additional acidic substances; (2) It is necessary to go through multiple stages of catalytic steps in coordination, which makes the entire production process very complicated and has significant cost issues.

[0008] CN101885978A discloses a method for directly producing alkane fuel from lignin, which uses an acid-metal bifunctional catalyst to catalytically degrade lignin under high temperature and high pressure reaction conditions, and simultaneously couples the intermediate products of lignin degradation with hydrogenation and deoxygenation to obtain alkylcycloalkane fuel. This scheme has many defects: (1) a large amount of sulfuric acid or phosphoric acid is required to adjust the pH value of the aqueous solution, and the acidic aqueous solution will cause serious corrosion to the equipment; (2) the reaction needs to be carried out under high temperature and high pressure reaction conditions, and the severe reaction conditions further accelerate the corrosion rate of the acidic aqueous solution to the equipment.

[0009] Therefore, there is still a need to study technical solutions suitable for industrial application for producing cyclohexane oil using lignin as raw material. Summary of the invention

[0010] The purpose of the present invention is to provide a technical solution that can realize the production of naphthenic oil using lignin as a raw material in simple steps under mild conditions, thereby laying a foundation for the industrial application of the production of naphthenic oil using lignin as a raw material.

[0011] In order to achieve the above objectives, the present invention provides the following three technical solutions.

[0012] In a first aspect, the present invention provides a method for preparing a hydrodeoxygenation catalyst, wherein the method comprises:

[0013] The β-type molecular sieve is treated with a first treating agent to obtain a first carrier precursor; wherein the first treating agent is selected from at least one of ethylenediaminetetraacetic acid (EDTA) and octanoylhydroxamic acid; the first carrier precursor is treated with sodium hydroxide to obtain a second carrier precursor;

[0014] The second carrier precursor is treated with a second treating agent to obtain a third carrier precursor; wherein the second treating agent is selected from at least one of disodium ethylenediaminetetraacetate (EDTA-2Na), tetrasodium diaminetetraacetate, sodium gluconate, and sodium citrate;

[0015] The third carrier precursor is subjected to ammonium ion exchange and then calcined in an oxygen atmosphere to obtain a catalyst carrier;

[0016] The catalyst carrier is mixed with a solution containing a ruthenium salt and urea, and placed at 115-135° C. for not less than 20 hours to obtain a catalyst precursor; wherein the mass content of ruthenium is 1-20% based on the mass of ruthenium and the catalyst carrier being 100%;

[0017] The catalyst precursor is reduced in an oxygen-free mixed gas atmosphere containing hydrogen to obtain a hydrodeoxygenation catalyst.

[0018] In the technical solution provided by the present invention, β-type molecular sieve is firstly subjected to dealumination treatment with ethylenediaminetetraacetic acid and / or octanoylhydroxamic acid, and then subjected to desiliconization treatment with sodium hydroxide, and then subjected to dealumination treatment with a second treatment agent (disodium ethylenediaminetetraacetic acid and / or tetrasodium diaminetetraacetic acid and / or sodium gluconate and / or sodium citrate), and then subjected to ammonium ion exchange and calcination to obtain a modified molecular sieve, and the modified molecular sieve obtained by the special treatment is used as a carrier to load ruthenium in a urea solution environment to obtain a special modified β molecular sieve loaded with ruthenium catalyst. When ruthenium is loaded in a urea solution environment, urea slowly decomposes in water and gradually releases NH 3 , causing the pH value to rise slowly, and the ruthenium particles in the solution gradually precipitate into the pores of the carrier, so that the ruthenium is evenly distributed in the pores of the carrier. The catalyst contains two active components: a hydrogenation or hydrogen transfer active center composed of ruthenium metal element, and a catalyst carrier composed of a special modified β molecular sieve.

[0019] According to a preferred embodiment of the first aspect, the mass content of ruthenium is 3-8% based on the mass of ruthenium and the catalyst carrier being 100%; further, the mass content of ruthenium is 5% based on the mass of ruthenium and the catalyst carrier being 100%.

[0020] According to a preferred embodiment of the first aspect, the mass concentration of ruthenium element in the solution containing ruthenium salt and urea is 0.41-1.09%, based on the mass of the solution containing ruthenium salt and urea as 100%.

[0021] According to a preferred embodiment of the first aspect, the β-type molecular sieve is Hβ-type molecular sieve; further, the β-type molecular sieve is SiO 2 With Al 2 O 3 Hβ molecular sieve with a molar ratio of 40 is Hβ 40 .

[0022] According to a preferred embodiment of the first aspect, the ruthenium salt is selected from at least one of ruthenium trichloride and ruthenium nitrate.

[0023] According to a preferred embodiment of the first aspect, the beta molecular sieve is treated with a first treating agent to obtain a first carrier precursor by the following method:

[0024] The molecular sieve β molecular sieve is mixed with the first treating agent solution, and then the mixture is reflux-heated, and the reflux-heated product is subjected to solid-liquid separation, washing, and drying to obtain a first carrier precursor;

[0025] Further, the concentration of the first treatment agent in the first treatment agent solution is 0.05-0.25 mol / L (based on the volume of the first treatment agent solution);

[0026] Further, the temperature of reflux heating is 100-110°C;

[0027] Further, the reflux heating time is 4-6h;

[0028] Furthermore, solid-liquid separation is achieved by centrifugation and filtration.

[0029] According to a preferred embodiment of the first aspect, the first carrier precursor is treated with sodium hydroxide to obtain the second carrier precursor by the following method:

[0030] The first carrier precursor is mixed with a sodium hydroxide solution, and then the mixture is heated, and the heated product is subjected to solid-liquid separation, washing, and drying to obtain a second carrier precursor;

[0031] Further, the concentration of sodium hydroxide in the sodium hydroxide solution is 0.1-0.4 mol / L (based on the volume of the sodium hydroxide solution);

[0032] Further, the heating temperature is 60-80°C;

[0033] Further, the heating time is 1-1.5h;

[0034] Furthermore, solid-liquid separation is achieved by centrifugation and filtration.

[0035] According to a preferred embodiment of the first aspect, the second carrier precursor is treated with the second treating agent to obtain the third carrier precursor by the following method:

[0036] The second carrier precursor is mixed with the second treating agent solution, and the mixture is reflux-heated, and the reflux-heated product is subjected to solid-liquid separation, washing, and drying to obtain a third carrier precursor;

[0037] Further, the concentration of the second treatment agent in the second treatment agent solution is 0.05-0.25 mol / L (based on the volume of the second treatment agent solution);

[0038] Further, the temperature of reflux heating is 100-110°C;

[0039] Further, the reflux heating time is 4-6h;

[0040] Furthermore, solid-liquid separation is achieved by centrifugation and filtration.

[0041] According to a preferred embodiment of the first aspect, the third carrier precursor is exchanged with ammonium ions in the following manner:

[0042] The third carrier precursor was NH 4 NO3 The solution undergoes ion exchange no less than 3 times;

[0043] Furthermore, NH 4 NO 3 NH in solution 4 NO 3 The concentration is 0.5-1.5 mol / L (NH 4 NO 3 The volume of the solution is taken as the basis).

[0044] According to a preferred embodiment of the first aspect, the calcination temperature in the oxygen atmosphere is 550-600°C.

[0045] According to a preferred embodiment of the first aspect, the calcination time in an oxygen atmosphere is 3.5-5 hours.

[0046] According to a preferred embodiment of the first aspect, the calcination environment for calcination in an oxygen atmosphere is an air environment.

[0047] According to a preferred embodiment of the first aspect, before calcination in an oxygen atmosphere, the carrier precursor that has completed the ammonium ion exchange is centrifuged, washed, and dried;

[0048] Furthermore, the drying temperature is 80-100°C.

[0049] According to a preferred embodiment of the first aspect, the solution containing ruthenium salt and urea is prepared by the following method:

[0050] The ruthenium salt and urea are mixed with water, and ultrasonically dissolved and dispersed for 10-30 minutes to obtain a solution containing the ruthenium salt and urea.

[0051] According to a preferred embodiment of the first aspect, the molar ratio of ruthenium to urea in the ruthenium salt is 1:5-10.

[0052] According to a preferred embodiment of the first aspect, the catalyst support is mixed with a solution containing a ruthenium salt and urea by the following method:

[0053] The catalyst carrier is added into a solution containing ruthenium salt and urea, stirred for 10-20 minutes, and then maintained under vacuum for 25-40 minutes to obtain a mixture.

[0054] According to a preferred embodiment of the first aspect, the catalyst carrier is mixed with a solution containing a ruthenium salt and urea and then placed at 120-125° C. for not less than 20 h (eg, 24 h) to obtain a catalyst precursor.

[0055] According to a preferred embodiment of the first aspect, the catalyst carrier is mixed with a solution containing a ruthenium salt and urea, and the product obtained is subjected to solid-liquid separation, washing, and drying to obtain a catalyst precursor;

[0056] Furthermore, the drying temperature is 80-100°C.

[0057] According to a preferred embodiment of the first aspect, the volume content of hydrogen is 5-35% (eg 10%) based on the total volume of the oxygen-free mixed gas containing hydrogen.

[0058] According to a preferred embodiment of the first aspect, the hydrogen-containing oxygen-free mixed gas atmosphere is a mixed gas atmosphere of hydrogen and argon.

[0059] According to a preferred embodiment of the first aspect, during the reduction process, the flow rate of the hydrogen-containing oxygen-free mixed gas is 50-80 mL / min.

[0060] According to a preferred embodiment of the first aspect, the reduction of the catalyst precursor in an oxygen-free mixed gas atmosphere containing hydrogen is achieved by the following method:

[0061] The catalyst precursor is heated from room temperature to 400±5°C in an oxygen-free mixed gas atmosphere containing hydrogen and maintained at this temperature for not less than 3 hours;

[0062] Furthermore, the heating rate is 100-400°C / h (eg, 187.5°C / h).

[0063] In a second aspect, the present invention provides a hydrodeoxygenation catalyst prepared by the method for preparing the hydrodeoxygenation catalyst provided in the first aspect.

[0064] In a third aspect, the present invention provides a method for producing cycloalkanes from lignin, wherein the method comprises:

[0065] Lignin, the hydrodeoxygenation catalyst provided in the second aspect and water are mixed and reacted in a hydrogen environment at a hydrogen pressure of 0.1-5 MPa and 180-300° C. After the reaction, solid-liquid separation and liquid-liquid separation (separation of organic phase and inorganic phase) are performed to obtain hydrocarbon products.

[0066] According to a preferred embodiment of the third aspect, the particle size of the lignin does not exceed 200 meshes.

[0067] According to a preferred embodiment of the third aspect, the mass ratio of lignin to the hydrodeoxygenation catalyst provided by the second aspect is 0.5-2:1.

[0068] According to a preferred embodiment of the third aspect, the mass ratio of lignin to water is 1:5-100.

[0069] According to a preferred embodiment of the third aspect, the liquid-liquid separation is achieved by extraction with ethyl acetate and / or dichloromethane.

[0070] According to a preferred embodiment of the third aspect, the product after the reaction is cooled to room temperature using cooling water or liquid nitrogen before solid-liquid separation or liquid-liquid separation is performed.

[0071] According to a preferred embodiment of the third aspect, the reaction time is 0.5-36h.

[0072] According to a preferred embodiment of the third aspect, the reaction is carried out under stirring conditions;

[0073] Furthermore, the stirring speed is 600-1000 rpm.

[0074] According to a preferred embodiment of the third aspect, the lignin is preferably enzymatically hydrolyzed lignin.

[0075] The technical solution provided by the present invention can realize the conversion of lignin raw materials into cycloalkanes by catalytic hydrodeoxygenation in one pot, with simple process, mild reaction conditions, no need to add additional organic solvents during the reaction, and the hydrocarbon products after the reaction do not contain additional organic solvents and have a high hydrocarbon content, which has the potential to produce high value-added products. Compared with the prior art, it has the following beneficial effects:

[0076] 1. The technical solution provided by the present invention uses lignin as raw material. Lignin is a renewable biomass resource with abundant reserves in nature. It has a wide range of sources, low cost, and meets the requirements of sustainable development.

[0077] 2. The technical solution provided by the present invention can convert the waste lignin of the papermaking industry into high-value-added cycloalkane chemicals, realize the green and efficient utilization of chemical resources, and at the same time reduce the environmental pollution and resource waste caused by the emission of lignin from the papermaking industry.

[0078] 3. The solvent used in the technical solution provided by the present invention is water, the reaction process is green, environmentally friendly and pollution-free, and the product oil obtained by the one-pot method is insoluble in water and can be separated from water, and the product oil is easily separated from the solvent.

[0079] 4. The technical solution provided by the present invention has a reaction temperature of 180-300°C and a hydrogen pressure of 0.1-6MPa, and the reaction conditions are mild.

[0080] 5. The catalyst provided by the technical solution of the present invention can be recycled and easily regenerated. DETAILED DESCRIPTION

[0081] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be construed as limiting the applicable scope of the present invention.

[0082] Hβ used in the embodiments of the present invention 40 The molecular sieve was purchased from Tianjin Nankai Catalyst Factory with the following parameters: silicon-aluminum molar ratio 40:1, specific surface area>640m 2 / g, cyclohexane adsorption ≥15%, relative crystallinity ≥90%.

[0083] The enzymatic lignin used in the examples of the present invention was purchased from Shandong Longli Biotechnology Co., Ltd. The lignin raw material was corn cobs, and the model name was enzymatic lignin.

[0084] Example 1

[0085] This embodiment provides a hydrodeoxygenation catalyst, which is prepared by the following method:

[0086] 3 g of Hβ 40 The molecular sieve is mixed with 30 mL of 0.1 mol / L ethylenediaminetetraacetic acid solution, and then the mixture is heated to reflux at 105-110° C. for 6 h for dealumination treatment, and the product after dealumination treatment is centrifuged, filtered, washed, and dried to obtain a first carrier precursor;

[0087] The first carrier precursor was mixed with 30 mL of a sodium hydroxide solution having a sodium hydroxide concentration of 0.1 mol / L, and the mixture was stirred at 65° C. for 1 h for desiliconization, and the product after the desiliconization was centrifuged, filtered, washed, and dried to obtain a second carrier precursor;

[0088] The second carrier precursor is mixed with 30 mL of 0.1 mol / L ethylenediaminetetraacetic acid disodium solution, and the mixture is refluxed at 105-110° C. for 6 h for dealumination treatment, and the refluxed product is centrifuged, filtered, washed, and dried to obtain a third carrier precursor;

[0089] The third carrier precursor was washed with 20 mL of NH 4 NO 3 The concentration of NH 4 NO 3 The solution was subjected to ion exchange three times; then centrifuged, washed, dried at 100°C, and calcined at 550°C for 5h in an air atmosphere to obtain the modified catalyst support Hβ 40 -Ⅰ;

[0090] Weigh 0.25 g of anhydrous ruthenium trichloride and 0.434 g of urea, add them into 25 mL of ultrapure water, ultrasonically dissolve and disperse for 15 min to obtain a solution containing ruthenium trichloride and urea, and then add 2.31 g of catalyst carrier Hβ to the above solution. 40 -Ⅰ, after stirring for 10 min, keep it in vacuum for 30 min, then transfer it to a 50 mL hydrothermal kettle and keep it at 120 ° C for 24 h, then centrifuge, filter, wash, and dry at 80 ° C for 24 h to obtain a catalyst precursor;

[0091] The catalyst precursor was placed in a tubular furnace in a hydrogen and argon mixed gas atmosphere (the volume content of hydrogen in the mixed gas was 10%) for reduction. The specific procedure was: the temperature in the tubular furnace was raised from room temperature for 2 hours to 400°C and maintained for 3 hours, and the gas flow rate of the hydrogen and argon mixed gas was 60 mL / min; the reduced product was cooled to room temperature to obtain a hydrodeoxygenation catalyst 5%Ru / Hβ 40 -Ⅰ.

[0092] Example 2

[0093] This embodiment provides a hydrodeoxygenation catalyst. The preparation method thereof is different from that of embodiment 1 only in that the sodium hydroxide concentration of the sodium hydroxide solution used is 0.2 mol / L. The obtained catalyst carrier is named Hβ 40 -Ⅱ, the prepared hydrodeoxygenation catalyst is named 5%Ru / Hβ 40 -I I.

[0094] Example 3

[0095] This embodiment provides a hydrodeoxygenation catalyst. The preparation method thereof is different from that of embodiment 1 only in that the sodium hydroxide concentration of the sodium hydroxide solution used is 0.3 mol / L. The obtained catalyst carrier is named Hβ 40 -ⅠII, the prepared hydrodeoxygenation catalyst is named 5%Ru / Hβ 40 -III.

[0096] Example 4

[0097] This embodiment provides a hydrodeoxygenation catalyst. The preparation method thereof is different from that of embodiment 1 only in that the sodium hydroxide concentration of the sodium hydroxide solution used is 0.05 mol / L. The obtained catalyst carrier is named Hβ 40 -IV, the prepared hydrodeoxygenation catalyst is named 5%Ru / Hβ 40 -IV.

[0098] Example 5

[0099] This embodiment provides a hydrodeoxygenation catalyst, and the preparation method thereof is different from that of the embodiment 1 only in that the catalyst carrier Hβ is added to the solution containing ruthenium trichloride and urea. 40 -Ⅰ, the mass content of ruthenium is 1% based on the mass of ruthenium and catalyst carrier as 100%; the prepared hydrodeoxygenation catalyst is named 1%Ru / Hβ 40 -Ⅰ.

[0100] Example 6

[0101] This embodiment provides a hydrodeoxygenation catalyst, and the preparation method thereof is different from that of the embodiment 1 only in that the catalyst carrier Hβ is added to the solution containing ruthenium trichloride and urea. 40 -Ⅰ, the mass content of ruthenium is 2.5% based on the mass of ruthenium and catalyst carrier as 100%; the prepared hydrodeoxygenation catalyst is named 2.5%Ru / Hβ 40 -Ⅰ.

[0102] Example 7

[0103] This embodiment provides a hydrodeoxygenation catalyst, and the preparation method thereof is different from that of the embodiment 1 only in that the catalyst carrier Hβ is added to the solution containing ruthenium trichloride and urea. 40 -Ⅰ, the mass content of ruthenium is 8% based on the mass of ruthenium and catalyst carrier as 100%; the prepared hydrodeoxygenation catalyst is named 8%Ru / Hβ 40 -Ⅰ.

[0104] Example 8

[0105] This embodiment provides a hydrodeoxygenation catalyst, and the preparation method thereof is different from that of the embodiment 1 only in that the catalyst carrier Hβ is added to the solution containing ruthenium trichloride and urea. 40 -Ⅰ, the mass content of ruthenium is 2.5% based on the mass of ruthenium and catalyst carrier as 100%; the prepared hydrodeoxygenation catalyst is named 8%Ru / Hβ 40 -Ⅰ.

[0106] Example 9

[0107] This embodiment provides a hydrodeoxygenation catalyst, and the preparation method thereof is different from that of the embodiment 1 only in that the catalyst carrier Hβ is added to the solution containing ruthenium trichloride and urea. 40 -Ⅰ, the mass content of ruthenium is 10% based on the mass of ruthenium and catalyst carrier as 100%; the prepared hydrodeoxygenation catalyst is named 10%Ru / Hβ 40 -Ⅰ.

[0108] Example 10

[0109] This embodiment provides a hydrodeoxygenation catalyst, and the preparation method thereof is different from that of the embodiment 1 only in that the catalyst carrier Hβ is added to the solution containing ruthenium trichloride and urea. 40 -Ⅰ, the mass content of ruthenium is 15% based on the mass of ruthenium and catalyst carrier as 100%; the prepared hydrodeoxygenation catalyst is named 15%Ru / Hβ 40 -Ⅰ.

[0110] Embodiment 11

[0111] This embodiment provides a hydrodeoxygenation catalyst, and the preparation method thereof is different from that of the embodiment 1 only in that the catalyst carrier Hβ is added to the solution containing ruthenium trichloride and urea. 40 -Ⅰ, the mass content of ruthenium is 20% based on the mass of ruthenium and catalyst carrier as 100%; the prepared hydrodeoxygenation catalyst is named 20%Ru / Hβ 40 -Ⅰ.

[0112] Comparative Example 1

[0113] This comparative example provides a hydrodeoxygenation catalyst, which is prepared by the following method:

[0114] Weigh 0.25 g of anhydrous ruthenium trichloride and 0.434 g of urea, add them into 25 mL of ultrapure water, ultrasonically dissolve and disperse for 15 min to obtain a solution containing ruthenium trichloride and urea, and then add 2.31 g of catalyst carrier Hβ to the above solution. 40 , stirred for 10 min and kept under vacuum for 30 min, then transferred to a 50 mL hydrothermal autoclave and kept at 120 ° C for 24 h, and then centrifuged, filtered, washed, and dried at 80 ° C for 24 h to obtain a catalyst precursor;

[0115] The catalyst precursor was placed in a tubular furnace in a hydrogen and argon mixed gas atmosphere (the volume content of hydrogen in the mixed gas was 10%) for reduction. The specific procedure was: the temperature in the tubular furnace was raised from room temperature for 2 hours to 400°C and maintained for 3 hours, and the gas flow rate of the hydrogen and argon mixed gas was 60 mL / min; the reduced product was cooled to room temperature to obtain a hydrodeoxygenation catalyst 5%Ru / Hβ 40 .

[0116] Example 12

[0117] This embodiment provides a method for producing cycloalkanes from lignin, wherein the method comprises:

[0118] 1.0 g of 200-mesh enzymatic lignin (the raw material is corncob lignin, the model is enzymatic lignin), 0.5 g of hydrodeoxygenation catalyst and 20 mL of water are added to a 50 mL intermittent reactor and mixed. After hydrogen is introduced into the reactor to replace the gas three times, the hydrogen is filled to 3 MPa, the stirring speed is 800 rpm, the temperature is raised to 280 ° C, and the reaction is carried out for 12 hours. After the reaction is completed, solid-liquid separation and liquid-liquid separation (using ethyl acetate for extraction and then separating the organic phase ethyl acetate from the inorganic phase water) are carried out to obtain hydrocarbon products.

[0119] The hydrodeoxygenation catalysts used are those provided in Examples 1 to 12 and Comparative Example 1.

[0120] The data of lignin carbon conversion rate, oil yield and cycloalkane yield are shown in Table 1.

[0121] Embodiment 13

[0122] The present embodiment provides a method for producing cycloalkanes from lignin, which differs from Embodiment 12 in that the types of lignin are different, and 200-mesh organic solvent lignin (purchased from Shandong Longli Biotechnology Co., Ltd., the raw material is corncob lignin, and the model is organic solvent extraction type lignin), 200-mesh alkali lignin (purchased from Shandong Longli Biotechnology Co., Ltd., the raw material is corncob lignin, and the model is alkaline hydrolysis type lignin), 200-mesh birch powder, 200-mesh pine powder, 200-mesh poplar powder, and 200-mesh corncob powder are selected respectively. The hydrodeoxygenation catalyst used is the hydrodeoxygenation catalyst provided in Embodiment 1.

[0123] Embodiment 14

[0124] This embodiment provides a method for producing cycloalkanes from lignin, which differs from Embodiment 12 in that the hydrodeoxygenation catalyst is recycled, and the hydrodeoxygenation catalyst used is the hydrodeoxygenation catalyst provided in Embodiment 1, which is recycled 1, 2, and 3 times respectively.

[0125] Embodiment 15

[0126] This embodiment provides a method for producing cycloalkanes from lignin, which differs from Embodiment 12 in that the hydrodeoxygenation catalyst used is the product of the catalyst after three cycles in Embodiment 14 calcined at 550° C. for 3 hours in an air atmosphere.

[0127] The data of lignin carbon conversion rate, oil yield and cycloalkane yield are shown in Table 1.

[0128] Table 1

[0129]

[0130] From the data in Table 1, it can be seen that ethylenediaminetetraacetic acid, sodium hydroxide, and disodium ethylenediaminetetraacetic acid are used step by step to treat molecular sieve Hβ 40 After modification, the ability to catalyze the conversion of lignin into naphthenic oil after the final loading of Ru metal can be improved, and other types of lignin and biomass can also be catalyzed into naphthenic oil. The catalyst also has a certain recycling ability.

Claims

1. A method for preparing a hydrodeoxygenation catalyst, wherein: The method includes: The beta-type molecular sieve is treated with a first treating agent to obtain a first carrier precursor; wherein the first treating agent is selected from at least one of ethylenediaminetetraacetic acid (EDTA) and octanoylhydroxamic acid; The first carrier precursor is treated with sodium hydroxide to obtain a second carrier precursor; The second carrier precursor is treated with a second treating agent to obtain a third carrier precursor; wherein the second treating agent is selected from at least one of disodium ethylenediaminetetraacetate (EDTA-2Na), tetrasodium diaminetetraacetate, sodium gluconate, and sodium citrate; The third carrier precursor is subjected to ammonium ion exchange and then calcined in an oxygen atmosphere to obtain a catalyst carrier; The catalyst carrier is mixed with a solution containing a ruthenium salt and urea, and placed at 115-135° C. for not less than 20 hours to obtain a catalyst precursor; wherein the mass content of ruthenium is 1-20% based on the mass of ruthenium and the catalyst carrier being 100%; The catalyst precursor is reduced in an oxygen-free mixed gas atmosphere containing hydrogen to obtain a hydrodeoxygenation catalyst.

2. The method according to claim 1, wherein: Hβ molecular sieve for β-type molecular screening; and / or The ruthenium salt is selected from at least one of ruthenium trichloride and ruthenium nitrate.

3. The method according to claim 1, wherein: The beta molecular sieve is treated with the first treating agent to obtain the first carrier precursor by the following method: The molecular sieve β molecular sieve is mixed with the first treating agent solution, and then the mixture is reflux-heated, and the reflux-heated product is subjected to solid-liquid separation, washing, and drying to obtain a first carrier precursor; Wherein, the concentration of the first treatment agent in the first treatment agent solution is 0.05-0.25 mol / L; The reflux heating temperature is 100-110°C.

4. The method according to claim 1, wherein: The first carrier precursor is treated with sodium hydroxide to obtain the second carrier precursor in the following manner: The first carrier precursor is mixed with a sodium hydroxide solution, and then the mixture is heated, and the heated product is subjected to solid-liquid separation, washing, and drying to obtain a second carrier precursor; Wherein, the concentration of sodium hydroxide in the sodium hydroxide solution is 0.1-0.4 mol / L; The heating temperature is 60-80°C.

5. The method according to claim 1, wherein: The second carrier precursor is treated with the second treating agent to obtain the third carrier precursor by the following method: The second carrier precursor is mixed with the second treating agent solution, and the mixture is reflux-heated, and the reflux-heated product is subjected to solid-liquid separation, washing, and drying to obtain a third carrier precursor; Wherein, the concentration of the second treatment agent in the second treatment agent solution is 0.05-0.25 mol / L; The reflux heating temperature is 100-110°C.

6. The method according to claim 1, wherein: The calcination temperature is 550-600° C. and the calcination time is 3.5-5 h in an oxygen atmosphere; and / or The calcination environment for calcination in an oxygen atmosphere is an air environment.

7. The method according to claim 1, wherein: The mass content of ruthenium is 3-8% based on the mass of ruthenium and the catalyst carrier as 100%; and / or The molar ratio of ruthenium to urea in the ruthenium salt is 1:5-10; and / or Taking the mass of the solution containing the ruthenium salt and the urea as 100%, the mass concentration of the ruthenium element in the solution containing the ruthenium salt and the urea is 0.41-1.09%.

8. The method according to claim 1, wherein: The volume content of hydrogen is 5-35% based on the total volume of the oxygen-free mixed gas containing hydrogen; and / or The oxygen-free mixed gas atmosphere containing hydrogen is a mixed gas atmosphere of hydrogen and argon; and / or During the reduction process, the flow rate of the hydrogen-containing oxygen-free mixed gas is 50-80 mL / min.

9. The method according to claim 1, wherein: The reduction of the catalyst precursor in an oxygen-free mixed gas atmosphere containing hydrogen is achieved by the following method: The catalyst precursor was heated from room temperature to 400°C in an oxygen-free mixed gas atmosphere containing hydrogen and maintained for 3 hours; The heating rate is 100-400°C / h.

10. A hydrodeoxygenation catalyst prepared by the method for preparing a hydrodeoxygenation catalyst according to any one of claims 1 to 9.

11. A method for producing cycloalkanes from lignin, wherein: The method includes: Lignin, the hydrodeoxygenation catalyst according to claim 10 and water are mixed and reacted in a hydrogen environment at a hydrogen pressure of 0.1-5 MPa and 180-300° C. After the reaction, solid-liquid separation and liquid-liquid separation are performed to obtain hydrocarbon products.

12. The method according to claim 11, wherein: The mass ratio of lignin to the hydrodeoxygenation catalyst provided in the second aspect is 0.5-2:1; and / or The mass ratio of lignin to water is 1:5-100; and / or The particle size of the lignin does not exceed 200 mesh; and / or The lignin is enzymatically hydrolyzed lignin.

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