Hydrodeoxygenation catalysts, methods for making and using the same

Abstract

A kind of hydrodeolefin catalyst, mixture of metal oxide and alumina is used as carrier, which is loaded with molecular sieve and active component;Metal oxide is selected from at least one of CeO2, ZrO2 and TiO2, and active component is Pt and / or Pd;The catalyst is characterized by TEM-EDS method, and the proportion of the amount of molecular sieve directly interacting with active metal in the total amount of molecular sieve is 60-100% calculated by silicon element.The metal oxide in the catalyst of the present application can improve the interaction between the active metal, promote the transfer of electron of metal oxide to active metal, thereby improving the activity of the catalyst;Molecular sieve is loaded on the outer surface of the catalyst instead of kneading with the carrier, which is beneficial to improve the contact surface of molecular sieve and active metal, and is also beneficial to load molecular sieve on the active site of active metal, fully exert the ability of molecular sieve to provide H proton, improve the hydrogenation activity of the catalyst;It also increases the utilization rate of molecular sieve, thus reduces the amount of molecular sieve, and reduces the cost of catalyst.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil hydrogenation, in particular to a hydrogenation deolefin catalyst and a preparation method thereof, which is suitable for hydrogenation of reformate. BACKGROUND

[0002] In order to adapt to the chemical transformation development of oil refining enterprises, a large number of reforming devices are newly built to generate aromatic hydrocarbons. The reformate contains a large amount of aromatic hydrocarbons, but still contains a small amount of olefins. This part of olefins is easy to accumulate in the reflux aromatic hydrocarbons during the aromatic extraction process, affecting the content of aromatic hydrocarbons, on the other hand, it is easy to cause pollution to the extraction solvent by polymerization, and the oxidation reaction of olefins generates organic acid to cause serious corrosion of the extraction system equipment. In addition, if the olefins are not removed, it may also cause the bromine index and acid washing color of the aromatic product to be unqualified, and the bromine index and copper sheet corrosion test of the solvent oil to be unqualified. Therefore, the reformate needs to be treated by deolefin.

[0003] CN201710408985.5 discloses a catalyst and a preparation method for diene hydrogenation. The composition of the catalyst, in terms of oxide mass, includes the following components: an alumina carrier with a large pore structure accounts for 91.0-98.5wt%, an active component of palladium oxide 1.0-5.5wt%, an active component of gold oxide 0.5-3.5wt%, the carrier uses chitosan as a pore expander, the mesopore and macropore are adjustable, and the La2O3 and K2O content on the surface of the carrier is 1.05-1.6 times that of the internal La2O3 and K2O content. The catalyst has high diene hydrogenation activity, low noble metal active component loss rate, and long operation cycle.

[0004] CN202011158625.2 discloses a preparation method of a reformate hydrogenation deolefin catalyst, including the following contents: (1) impregnating the alumina carrier with an impregnation solution containing an additive, then drying the treated material, and then sulfidizing the dried material to obtain a catalyst precursor; (2) preparing an impregnation solution containing Pt and Pd, adjusting the pH value of the impregnation solution to 3-5, then impregnating the catalyst precursor obtained in step (1), and then drying and reducing the impregnated catalyst precursor in an inert atmosphere to obtain a reformate hydrogenation deolefin catalyst. The catalyst prepared by the method has high deolefin activity and low aromatic loss.

[0005] CN201410588224.9 discloses a selective hydrogenation catalyst for reformed oil, its preparation method, and its application. The catalyst comprises the following components by mass fraction: 0.05-0.5% active component, 0.5-10% promoter, and the remainder as a support; the active component is at least one selected from Pt, Pd, and Ru; the promoter is one or two selected from Na, K, Mg, Ca, Co, Fe, Ni, Mo, and Cu; the support is a porous Al₂O₃; the active component is distributed in an eggshell pattern on the support, and the thickness of the eggshell is less than 1 mm; the specific surface area of ​​the catalyst is 50-400 m². 2 / g, pore volume 0.2-1.2cm³ 3 / g, of which pores with a diameter of 5-50 nm account for 50-80% of the total pores. This catalyst requires a high hydrogen-to-oil volume ratio (hydrogen-to-oil ratio of 100-1000) and a low space velocity (feed space velocity of 1 h⁻¹). -1 -6h -1 Meeting product quality requirements under certain conditions leads to increased hydrogen consumption in the unit, and low feedstock space velocity increases the amount of precious metals loaded, thus increasing production costs.

[0006] CN200810104300.9 discloses a catalyst for selective hydrodeolefins treatment of continuous reformed gasoline and its preparation method. The catalyst is characterized by an eggshell-shaped distribution of the precious metal active component on the support. This has advantages in two aspects: firstly, it improves the utilization rate of the precious metal active component, reduces its content, and lowers the catalyst cost; secondly, it reduces the activity of aromatics hydrogenation, improves the selectivity of olefins hydrogenation, and reduces aromatics hydrogenation loss. However, the active metal in this catalyst is distributed in the outer shell. During operation or catalyst regeneration, catalyst wear can easily occur, leading to the loss of the precious metal in the outer shell and a decrease in catalyst activity. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention starts with the mechanism of olefin hydrogenation reaction and prepares a hydrogenation deolefination catalyst by improving the dispersion of active metals and adjusting the interaction between metals and supports. This catalyst has high olefin hydrogenation saturation activity and selectivity and is suitable for trickle bed and liquid phase hydrogenation processes.

[0008] To achieve the above technical objectives, the technical solution of the present invention is as follows:

[0009] The technical purpose of the first aspect of the present application is to provide a hydrodeolefin catalyst, which uses a mixture of metal oxides and alumina as a carrier, and is loaded with a molecular sieve and an active component; the metal oxides are selected from at least one of CeO2, ZrO2 and TiO2, and the active component is Pt and / or Pd; the catalyst is characterized by a TEM-EDS method, and the proportion of the amount of the molecular sieve directly interacting with the active metal to the total amount of the molecular sieve is 60-100%, preferably 65%-95%, more preferably 70%-90%, and most preferably 80%-90% in terms of the silicon element.

[0010] In the above catalyst, the molecular sieve directly interacting with the active metal refers to the molecular sieve being loaded on the surface of the active metal crystal sheet. In the proportion of the amount of the molecular sieve directly interacting with the active metal to the total amount of the molecular sieve, the total amount of the molecular sieve (in terms of the silicon element) represents the total content of the molecular sieve in the catalyst, and the amount of the molecular sieve directly interacting with the active metal refers to the content (in terms of the silicon element) of the molecular sieve within 2 nm from the outermost layer of the active metal crystal sheet. The proportion of the amount of the molecular sieve directly interacting with the active metal to the total amount of the molecular sieve is obtained by a TEM-EDS (transmission electron microscope-energy dispersive X-ray spectroscopy) method, and the instrument used is a Japan JEOL JEM2200FS type transmission electron microscope equipped with a scanning transmission accessory and an X-ray energy spectrum accessory of the United States EDAX company. The electron microscope acceleration voltage is 200KV, and in the STEM mode, the condenser diaphragm is taken as 2, and the Spote size is 0.5nm. The determination process is as follows: the catalyst particles are ground, a sample is prepared by a suspension method, 0.1g of the catalyst sample is placed in a 2mL container, and is dispersed by ultrasonic with anhydrous ethanol, the supernatant is taken, two-three drops are taken by a dropper, and are dropped on a sample net with a diameter of 3mm, and the sample to be tested is obtained after drying, and then the sample to be tested is observed and analyzed by TEM, and then the Si content at a distance of less than 2nm from the edge end point of the active phase observed by TEM is statistically analyzed by combining EDS, and the proportion of the amount of the molecular sieve directly interacting with the active metal to the total amount of the molecular sieve is obtained in terms of the corresponding peak area of Si. The proportion of the amount of the molecular sieve directly interacting with the active metal to the total amount of the molecular sieve in the present application is obtained by averaging the data obtained by selecting 40 TEM images combined with EDS analysis.

[0011] Further, the molecular sieve accounts for 1-10%, preferably 2-8%, and more preferably 3-5% of the total weight of the catalyst;

[0012] Further, the active component accounts for 0.01-0.5%, preferably 0.02-0.3% of the total weight of the catalyst in terms of the element; and the active component exists in the catalyst in the form of a noble metal oxide or an element.

[0013] Further, the dispersion of the active component is 70-100%; wherein the dispersion of the active component is determined by hydrogen-oxygen titration, for example, Pt, the chemical reaction formula of hydrogen-oxygen titration is formula (1)-(3):

[0014] Pt + H2→ PtH (catalyst) (1)

[0015] PtH + O2→ PtO + H2O (oxygen titration) (2)

[0016] PtO + H2→ PtH + H2O (hydrogen titration) (3)

[0017] Three hydrogen atoms are consumed to titrate one Pt atom by hydrogen-oxygen titration, and the ratio of the actual hydrogen consumption to the theoretical hydrogen consumption during the determination process is the dispersion of the noble metal.

[0018] Further, the metal oxide accounts for 3-20%, preferably 5-15%, of the total weight of the carrier.

[0019] Further, the pore volume of the carrier is 0.7-1.2 cm 3 / g, and the average pore size is 10-20 nm.

[0020] Further, the molecular sieve is selected from at least one of Y-type molecular sieve, ZSM-5 molecular sieve, β-type molecular sieve and MCM-41 molecular sieve.

[0021] The technical purpose of the second aspect of the present application is to provide a preparation method of the above-mentioned hydrogenation deolefin catalyst, comprising the following steps:

[0022] (1) mixing the metal oxide with the alumina precursor, the extrusion aid and the peptizing agent, kneading, shaping, drying and calcining to obtain a modified alumina carrier;

[0023] (2) loading the noble metal on the modified alumina carrier, drying and calcining to obtain a catalyst precursor.

[0024] (3) introducing the molecular sieve into the catalyst precursor, and then drying and calcining.

[0025] Further, before use, the catalyst further comprises a reduction process of the catalyst, and the noble metal is reduced to an element. The reduction conditions are as follows: hydrogen atmosphere, reduction temperature is 200-550℃, reduction pressure is 1.0-4.0 MPa, and reduction time is 3-10 hours.

[0026] Further, in step (1), the raw materials are mixed by any solid material mixing means available in the prior art to the extent considered to be sufficiently mixed by those skilled in the art.

[0027] Furthermore, the metal oxide described in step (1) has a weight content of 1-12 wt% in the carrier, preferably 3-8 wt%.

[0028] Furthermore, the alumina precursor in step (1) is selected from one or more of boehmite, gibbsite, trihydrate, boehmite, and diaspore; wherein, the alumina precursor preferably has a pore volume of 1.0-2.0 cm³ after being calcined in air at 500°C for 3 hours. 3 / g, a precursor of alumina with an average pore size of 10-20nm.

[0029] Furthermore, the extrusion aid described in step (1) is well known to those skilled in the art. As a more specific embodiment, the extrusion aid is selected from at least one of starch, polyethylene glycol, and guar gum.

[0030] Furthermore, the amount of the extrusion aid added, based on alumina, is 2-8 wt% of alumina, preferably 3-5 wt%.

[0031] Furthermore, the adhesive solvent used in step (1) is well known to those skilled in the art. As a more specific embodiment, the adhesive solvent is selected from at least one of nitric acid, phosphoric acid, and acetic acid.

[0032] Furthermore, the amount of the alumina precursor added, based on alumina, is 1-8 wt% of alumina, preferably 2-5 wt%; and the amount of water added is 50-150 wt% of alumina, preferably 80-120 wt%.

[0033] Furthermore, the drying conditions in step (1) are: temperature 90-200℃, time 3-6 hours; the calcination conditions are: temperature 500-850℃, time 3-6 hours.

[0034] Furthermore, the method for loading noble metals onto modified alumina is an impregnation method, which can be carried out using conventional methods in the prior art. Preferably, an organic or inorganic acid is added during the impregnation process. The organic or inorganic acid is selected from at least one of acetic acid, hydrochloric acid, hydrofluoric acid, nitric acid, and phosphoric acid, and the mass concentration of the solution, calculated as acid, is 1-5%. It is also preferred that an organic auxiliary agent is added during the impregnation process. The organic auxiliary agent is an alcohol or organic acid containing hydroxyl and / or carboxyl groups and having 3-10 carbon atoms. Specifically, it is selected from at least one of ethylene glycol, glycerol, butanediol, pentanediol, acetic acid, citric acid, malonic acid, succinic acid, and glutaric acid. The amount of the organic auxiliary agent added is 3-10 wt% of the alumina carrier, preferably 3-8 wt%.

[0035] Further, the noble metal salt is a platinum salt and / or a palladium salt, the platinum salt is at least one selected from chloroplatinic acid, dichlorotetrammine platinum, ammonium chloroplatinate, platinum chloride, platinum tetrachloride, dichlorodiformyl platinum, dinitrodiamino platinum and sodium tetranitroplatinic acid, with a concentration of 0.001-0.5 g / mL of platinum element in solution. The palladium salt is at least one selected from palladium chloride, palladium nitrate, palladium acetate, sodium tetrachloropalladate, dichlorotetrammine palladium, palladium trifluoroacetate, palladium diacetylacetone and palladium hexafluoroacetylacetone, with a concentration of 0.001-0.5 g / mL of palladium element in solution.

[0036] Further, the drying condition of step (2) is 60-100℃ and 3-6 hours. The calcination condition is 200-300℃ and 3-6 hours.

[0037] Further, the method of introducing the molecular sieve into the catalyst precursor in step (3) is not particularly limited, which can be directly mixing the catalyst precursor with the molecular sieve, or mixing the catalyst precursor with a molecular sieve precursor and then performing hydrothermal treatment.

[0038] Preferably, the method of introducing the molecular sieve into the catalyst precursor in step (3) is performed by at least one of the following ways:

[0039] (a) performing hydrothermal treatment of the catalyst precursor with a molecular sieve precursor, and then performing the drying and calcination of step (3);

[0040] (b) mixing the catalyst precursor with the ball-milled molecular sieve in the presence of a solvent, and then performing the drying and calcination of step (3).

[0041] According to the present application, it can be understood that the molecular sieve precursor can be a gel formed by hydrothermal treatment to generate the above-mentioned molecular sieve. Preferably, in way (a), the molecular sieve precursor includes a gel formed by mixing a silicon source and / or an aluminum source, a precipitant, a template agent and water. The preparation method is well known to those skilled in the art, which can form the molecular sieve by precipitation method or sol-gel method.

[0042] The types of the silicon source and / or the aluminum source, the precipitant and the template agent are well known to those skilled in the art. The silicon source is preferably at least one selected from sodium silicate, tetraethyl orthosilicate, silica sol and chromatographic silica gel. The aluminum source is preferably at least one selected from sodium metaaluminate, aluminum hydroxide and pseudo-boehmite. The precipitant is preferably at least one selected from sodium hydroxide, ammonia and potassium hydroxide. The template agent is preferably at least one selected from cetyltrimethylammonium bromide, ethylenediamine, n-butylamine, tetrapropylammonium bromide, ethanol, tetraethylammonium hydroxide, tetraethylammonium bromide, triethylamine, di-n-propylamine, diisopropylamine and methyl cellulose.

[0043] Further, when the molecular sieve is a silica-alumina molecular sieve, preferably, the molar composition of the gel is n(SiO2):n(Al2O3):n(Na2O):n(template):n(H2O)=(5-30):1:(1-10):(1-10):(100-300).

[0044] Further, when the molecular sieve is a silica molecular sieve, preferably, the molar composition of the gel is n(SiO2):n(Na2O):n(template):n(H2O)=100:(10-30):(10-30):(1500-3000).

[0045] The conditions of the hydrothermal treatment are selected in a wide range according to the molecular sieve to be obtained, and preferably, the conditions of the hydrothermal treatment include a temperature of 90-200℃, preferably 120-200℃, a pressure of 0.1-2MPa, a pH of 7.5-9, and a time of 5-48 hours.

[0046] Further, in the method (b), the particle size of the molecular sieve after ball milling is 0.1-10nm, more preferably 0.1-5nm. The use of this preferred embodiment is more conducive to the function of the molecular sieve. The parameters and equipment of ball milling are not particularly limited.

[0047] According to a preferred embodiment of the present application, the drying conditions in step (3) include a temperature of 90-200℃ and a time of 3-6 hours.

[0048] According to a preferred embodiment of the present application, the calcination conditions in step (3) include a temperature of 300-500℃ and a time of 3-6 hours.

[0049] The technical purpose of the third aspect of the present application is to provide a hydroprocessing method for the reforming generated oil, in which the oil is contacted with the hydrodeolefinization catalyst or the hydrodeolefinization catalyst prepared by the above method.

[0050] Further, in the above hydroprocessing method, the temperature for the catalyst to catalyze the hydrodeolefinization reaction of the reforming generated oil is 130-280℃, preferably 130-190℃, the pressure is 1.0-3.0MPa, and the volume ratio of hydrogen to raw oil is 10-1000.

[0051] The catalyst of the present application can effectively remove the olefins in the reforming generated oil with a bromine index higher than 3500mgBr / 100g oil, has a good selective deolefinization effect, and has a small loss of aromatic hydrocarbons.

[0052] Compared with the prior art, the catalyst of the present application has the following advantages:

[0053] (1) The addition of metal oxides in the hydrogenation deolefin catalyst of the present application is beneficial in improving the interaction between the metal oxides and the active metals, promoting the transfer of electrons from the metal oxides (such as Ce 4+ / Ce 3+ generated by the conversion of electrons to the active metals, thereby improving the activity of the catalyst. On the other hand, the metal oxides can block the sintering of alumina, which is beneficial to improve the pores of the carrier and the diffusion capacity of the macromolecular reactants, thereby improving the activity of the catalyst.

[0054] (2) The addition of molecular sieves in the hydrogenation deolefin catalyst of the present application and the loading of the molecular sieves on the outer surface of the catalyst instead of kneading with the carrier are beneficial in improving the contact between the molecular sieves and the active metals, and in loading the molecular sieves on the active sites of the active metals, thereby fully exerting the ability of the molecular sieves to provide H protons and improving the hydrogenation activity of the catalyst. On the other hand, the utilization rate of the molecular sieves is increased, thereby reducing the amount of molecular sieves used and the cost of the catalyst.

[0055] (3) In the preferred technical solution of the preparation method of the present application, organic or inorganic acids are added to the impregnation solution during the loading of noble metals, which is beneficial in occupying the basic sites on the surface of the carrier, improving the dispersion of the active metals, and thereby improving the active sites. On the other hand, the acidity of the catalyst can be improved, the ability of the catalyst to provide protons can be improved, and the hydrogenation reaction of substances prone to polymerization can be improved to prevent polymerization and cause the catalyst to be deactivated by carbon deposition.

[0056] (4) The catalyst of the present application is applied to the hydrogenation deolefin reaction of the reformate, which has good selectivity for deolefination and small loss of aromatic hydrocarbons.

[0057] Other features and advantages of the present application will be described in detail in the following specific embodiments. DETAILED DESCRIPTION

[0058] The following non-limiting examples can make those skilled in the art more fully understand the present application, but do not limit the present application in any way.

[0059] The noble metal composition of the catalyst provided by the present application can be characterized by inductively coupled plasma (ICP), and the composition of the auxiliary metal in the catalyst can be characterized by chemical colorimetry. The dispersion of the noble metal in the catalyst provided by the present application can be determined by hydrogen-oxygen titration. Taking Pt as an example, the chemical reaction formula of hydrogen-oxygen titration is formula (1) to formula (3):

[0060] Pt + H2→ PtH (catalyst) (1)

[0061] PtH + O2→ PtO + H2O (oxygen titration) (2)

[0062] PtO + H2→ PtH + H2O (hydrogen titration) (3)

[0063] It needs 3 hydrogen atoms to titrate 1 Pt atom by hydrogen-oxygen titration method. The dispersion of noble metal can be obtained according to the ratio of actual hydrogen consumption to theoretical hydrogen consumption in the determination process.

[0064] Example 1

[0065] (1) Mix cerium oxide, pseudo-boehmite, sesbania powder, nitric acid and deionized water uniformly, wherein the mass ratio of cerium oxide: pseudo-boehmite: sesbania powder, nitric acid: deionized water is 5:120:4:3:90, then knead, extrude into strips, then dry at 80°C for 10 hours, and calcine at 650°C for 3 hours to obtain a modified alumina carrier, wherein the content of cerium oxide is 5%.

[0066] (2) Impregnate a solution containing chloroplatinic acid and glycerol (content of 5% of the weight of the carrier) into the modified alumina carrier prepared in step (1), then dry at 80°C for 6 hours, and calcine at 300°C for 5 hours to obtain a catalyst precursor.

[0067] (3) Add sodium hydroxide, silica sol, sodium aluminate and ethylenediamine into deionized water, wherein the molar ratio of each component is n(SiO2):n(Al2O3):n(Na2O):n(n-butylamine):n(H2O) = 28:2:7:6:200, and stir to form a uniform sol, which is the precursor of ZSM-5 molecular sieve. Then mix it with the catalyst precursor prepared in step (2), and then hydrothermally treat it at 120°C, 1.0 MPa, pH = 8.5 for 20h; then filter, wash with deionized water three times, dry at 110°C for 3h, calcine at 450°C for 3h, and then reduce it with hydrogen, the reduction temperature is 400°C, the reduction pressure is 3.0 MPa, and the reduction time is 5 hours to obtain catalyst C-1.

[0068] The weight percentage of each component in catalyst C-1 is: Pt is 0.25%, ZSM-5 is 3.1%, and the rest is modified alumina carrier.

[0069] Example 2

[0070] (1) Mix zirconium oxide, pseudo-boehmite, sesbania powder, nitric acid and deionized water uniformly, wherein the mass ratio of cerium oxide: pseudo-boehmite: sesbania powder, nitric acid: deionized water is 5:120:4:3:90, then knead, extrude into strips, then dry at 80°C for 10 hours, and calcine at 750°C for 3 hours to obtain a modified alumina carrier, wherein the content of zirconium oxide is 5%.

[0071] (2) Impregnate the modified alumina carrier prepared in step (1) with a solution containing chloroplatinic acid and ethylene glycol (6% by weight of the carrier), then dry at 80°C for 6 hours and calcine at 300°C for 5 hours to obtain a catalyst precursor.

[0072] (3) Add sodium hydroxide, silica sol, sodium aluminate and ethylenediamine into deionized water, wherein the molar ratio of each component is n(SiO2):n(Al2O3):n(Na2O):n(ethylenediamine):n(H2O) = 24:3:6:3:180, stir until a homogeneous sol, i.e. a precursor of Y zeolite, is formed, then mix with the catalyst precursor prepared in step (2), and then hydrothermally treat at 150°C, 1.0 MPa, pH = 8.0 for 10 hours; then filter, wash with deionized water three times, dry at 110°C for 3 hours, calcine at 450°C for 3 hours, then reduce with hydrogen, the reduction temperature being 400°C, the reduction pressure being 3.0 MPa, and the reduction time being 5 hours, to obtain catalyst C-2.

[0073] The weight percentage of each component in catalyst C-2 is as follows: Pt is 0.25%, Y zeolite is 3.2%, and the rest is the modified alumina carrier.

[0074] Example 3

[0075] (1) Mix cerium oxide, pseudoboehmite, sesbania powder, nitric acid and deionized water uniformly, wherein the mass ratio of cerium oxide:pseudoboehmite:sesbania powder:nitric acid:deionized water is 5:120:4:3:90, then knead, extrude and shape, then dry at 80°C for 10 hours and calcine at 650°C for 3 hours to obtain a modified alumina carrier, wherein the content of cerium oxide is 5%.

[0076] (2) Impregnate the modified alumina carrier prepared in step (1) with a solution containing chloroplatinic acid and acetic acid (6% by weight of the carrier), then dry at 90°C for 5 hours and calcine at 250°C for 5 hours to obtain a catalyst precursor.

[0077] (3) The sodium metaaluminate, sodium hydroxide were dissolved in deionized water, then tetraethyl ammonium bromide was added, stirred vigorously, and slowly added silica sol, aged for 3h, wherein the molar ratio of each component was n(Si02):n(Al203):n(Na20):n(tetraethyl ammonium bromide):n(H20) = 25:1:6:5:250, the precursor of β molecular sieve was formed, then mixed with the catalyst precursor prepared in step (2), then hydrothermal treatment was carried out at 130℃, 1.0MPa, pH = 8.5 for 15h; then filtered, washed with deionized water three times, dried at 110℃ for 3h, calcined at 450℃ for 3h, then reduced with hydrogen, the reduction temperature was 500℃, the reduction pressure was 3.0MPa, and the reduction time was 5 hours, to obtain the catalyst C-3.

[0078] The weight percentage of each component in the catalyst C-3 was that the Pt was 0.28%, the β molecular sieve was 3.5%, and the rest was the modified alumina carrier.

[0079] Example 4

[0080] (1) The titanium oxide, pseudoboehmite, sesbania powder, nitric acid, and deionized water were mixed uniformly, wherein the mass ratio of the cerium oxide, pseudoboehmite, sesbania powder, nitric acid, and deionized water was 5:120:4:3:90, then kneaded, extruded into a strip, then dried at 80℃ for 10 hours, and calcined at 550℃ for 3 hours to obtain the modified alumina carrier, wherein the content of the titanium oxide was 5%.

[0081] (2) A solution containing palladium chloride and succinic acid (5% of the weight of the carrier) was impregnated into the modified alumina carrier prepared in step (1), then dried at 90℃ for 5 hours, and calcined at 250℃ for 5 hours to obtain the catalyst precursor.

[0082] (3) Cetyltrimethylammonium bromide and sodium hydroxide were mixed, then added to deionized water, after stirring, tetraethyl orthosilicate was added dropwise into the mixed solution, stirred for 30min, wherein the molar ratio of each component was n(Si02):n(Na20):n(cetyltrimethylammonium bromide):n(H20) = 11:2:3:200, the MCM-41 molecular sieve precursor was formed, then mixed with the catalyst precursor prepared in step (2), then hydrothermal treatment was carried out at 130℃, 1.0MPa, pH = 8.5 for 15h; then filtered, washed with deionized water three times, dried at 110℃ for 3h, calcined at 450℃ for 3h, then reduced with hydrogen, the reduction temperature was 500℃, the reduction pressure was 3.0MPa, and the reduction time was 5 hours, to obtain the catalyst C-4.

[0083] The weight percentage of each component in the catalyst C-4 was that the Pd was 0.15%, the MCM-41 molecular sieve was 2.5%, and the rest was the modified alumina carrier.

[0084] Example 5

[0085] (1) A mixture of cerium oxide, pseudoboehmite, sesbania powder, nitric acid and deionized water was prepared, wherein the mass ratio of cerium oxide, pseudoboehmite, sesbania powder, nitric acid and deionized water was 5:120:4:3:90, and then kneaded, extruded into a strip, dried at 80°C for 10 hours, and calcined at 650°C for 3 hours to obtain a modified alumina carrier, wherein the content of cerium oxide was 5%.

[0086] (2) A solution containing palladium chloride and acetic acid (content of 6% of the weight of the carrier) was impregnated into the modified alumina carrier prepared in step (1), then dried at 80°C for 5 hours, and calcined at 300°C for 5 hours to obtain a catalyst precursor.

[0087] (3) Sodium aluminate and sodium hydroxide were dissolved in deionized water, then tetraethylammonium bromide was added, stirred vigorously, and silica sol was slowly added dropwise and aged for 3h, wherein the molar ratio of each component was n(SiO2):n(Al2O3):n(Na2O):n(tetraethylammonium bromide):n(H2O) = 25:1:6:5:250, to form a precursor of β molecular sieve, which was then mixed with the catalyst precursor prepared in step (2), and then hydrothermally treated at 130°C, 1.0 MPa, and pH = 8.5 for 15h; then filtered, washed with deionized water three times, dried at 120°C for 3h, calcined at 500°C for 3h, and then reduced with hydrogen, the reduction temperature was 350°C, the reduction pressure was 2.0 MPa, and the reduction time was 10 hours, to obtain catalyst C-5.

[0088] The weight percentage of each component in catalyst C-5 was: Pd was 0.20%, β molecular sieve was 3.0%, and the rest was modified alumina carrier.

[0089] Example 6

[0090] (1) A mixture of cerium oxide, pseudoboehmite, sesbania powder, nitric acid and deionized water was prepared, wherein the mass ratio of cerium oxide, pseudoboehmite, sesbania powder, nitric acid and deionized water was 8:116:4:3:90, and then kneaded, extruded into a strip, dried at 80°C for 10 hours, and calcined at 650°C for 3 hours to obtain a modified alumina carrier, wherein the content of cerium oxide was 8%.

[0091] (2) A solution containing palladium chloride and citric acid (content of 6% of the weight of the carrier) was impregnated into the modified alumina prepared in step (1), then dried at 80°C for 6 hours, and calcined at 300°C for 5 hours to obtain a catalyst precursor.

[0092] (3) Sodium hydroxide, silica sol, sodium aluminate and ethylenediamine were added to deionized water, with the molar ratio of each component being n(SiO2):n(Al2O3):n(Na2O):n(ethylenediamine):n(H2O)=12:1:6:3:180. The mixture was stirred until a homogeneous sol was formed, which is the precursor of Y molecular sieve. The sol was then mixed with the catalyst precursor prepared in step (2), and then hydrothermally treated for 10 h at 150 °C, 1.0 MPa and pH=8.0. The mixture was then filtered, washed three times with deionized water, dried at 110 °C for 3 h, calcined at 400 °C for 3 h, and then reduced with hydrogen at 300 °C, 3.0 MPa and 10 h to obtain catalyst C-6.

[0093] The weight percentages of the components in catalyst C-6 are as follows: Pd is 0.30%, Y molecular sieve is 4.1%, and the remainder is modified alumina support.

[0094] Example 7

[0095] (1) Cerium oxide, boehmite, guar gum powder, nitric acid, and deionized water are mixed evenly, wherein the mass ratio of cerium oxide:boehmite:guar gum powder and nitric acid:deionized water is 5:120:4:3:90. Then the mixture is kneaded, extruded into strips, dried at 80°C for 10 hours, and calcined at 650°C for 3 hours to obtain a modified alumina carrier, wherein the content of cerium oxide is 5%.

[0096] (2) The modified alumina support prepared in step (1) is impregnated with a solution containing palladium chloride, chloroplatinic acid and citric acid (5% of the weight of the support), and then dried at 80°C for 5 hours and calcined at 300°C for 5 hours to obtain the catalyst precursor.

[0097] (3) Dissolve sodium aluminate and sodium hydroxide in deionized water, then add tetraethylammonium bromide, stir vigorously, slowly add silica sol, and age for 3 hours. The molar ratio of each component is n(SiO2):n(Al2O3):n(Na2O):n(tetraethylammonium bromide):n(H2O)=25:1:6:5:250 to form a precursor of β-type molecular sieve. Mix it with the catalyst precursor prepared in step (2), and then perform hydrothermal treatment at 130℃, 1.0MPa, and pH=8.5 for 15 hours. Then filter, wash three times with deionized water, dry at 120℃ for 3 hours, calcine at 500℃ for 3 hours, and then reduce with hydrogen at a reduction temperature of 500℃, a reduction pressure of 2.5MPa, and a reduction time of 10 hours to obtain catalyst C-7.

[0098] The weight percentages of the components in catalyst C-7 are as follows: Pt 0.15%, Pd 0.12%, β molecular sieve 3.5%, and the remainder is modified alumina support.

[0099] Example 8

[0100] (1) Mix cerium oxide, pseudoboehmite, sesbania powder, nitric acid and deionized water uniformly, wherein the mass ratio of cerium oxide: pseudoboehmite: sesbania powder, nitric acid: deionized water is 5:120:4:3:90, then knead, extrude into strips, then dry at 80°C for 10 hours, and calcine at 650°C for 3 hours to obtain a modified alumina carrier, wherein the content of cerium oxide is 5%.

[0101] (2) Impregnate a solution containing palladium chloride, chloroplatinic acid and citric acid (content of 6% of the weight of the carrier) into the modified alumina carrier prepared in step (1), then dry at 90°C for 6 hours, and calcine at 250°C for 5 hours to obtain a catalyst precursor.

[0102] (3) Add sodium hydroxide, silica sol, sodium aluminate and ethylenediamine into deionized water, wherein the molar ratio of each component is n(SiO2):n(Al2O3):n(Na2O):n(ethylenediamine):n(H2O)=12:1:6:3:180, stir until a uniform sol, i.e. a precursor of Y zeolite, is formed, then mix with the catalyst precursor prepared in step (2), and then hydrothermally treat at 150°C, 1.0 MPa, pH=8.0 for 10h; then filter, wash with deionized water three times, dry at 110°C for 3h, calcine at 500°C for 3h, then reduce with hydrogen, the reduction temperature is 500°C, the reduction pressure is 3.0 MPa, and the reduction time is 10 hours to obtain catalyst C-8.

[0103] The weight percentage of each component in catalyst C-8 is 0.11% of Pt, 0.19% of Pd, 3.6% of Y zeolite, and the rest is the modified alumina carrier.

[0104] Comparative Example 1

[0105] (1) Mix cerium oxide, pseudoboehmite, ZSM-5 zeolite, sesbania powder, nitric acid and deionized water uniformly, wherein the mass ratio of cerium oxide: pseudoboehmite: ZSM-5 zeolite: sesbania powder, nitric acid: deionized water is 5:115:4:4:3:90, then knead, extrude into strips, then dry at 80°C for 10 hours, and calcine at 650°C for 3 hours to obtain a modified alumina carrier, wherein the content of cerium oxide is 5%, and the content of ZSM-5 zeolite is 4.0%.

[0106] Other steps are the same as in Example 1 to obtain a comparative catalyst DC-1, wherein the weight percentage of each component in the comparative catalyst DC-1 is 0.25% of Pt, 3.1% of ZSM zeolite, 5.0% of cerium oxide, and the rest is alumina.

[0107] Comparative Example 2

[0108] The other steps are the same as in Example 1, except that the solution containing chloroplatinic acid is impregnated into the prepared modified alumina carrier, then dried at 80°C for 6 hours, and calcined at 300°C for 5 hours to obtain the catalyst precursor.

[0109] The weight percentage of each component in the comparative catalyst DC-2 is as follows: 0.25% of Pt, 3.1% of ZSM-5 molecular sieve, and the rest is modified alumina carrier.

[0110] Comparative Example 3

[0111] The other steps are the same as in Example 1, except that ZSM-5 molecular sieve is not added.

[0112] The weight percentage of each component in the comparative catalyst DC-3 is as follows: 0.25% of Pt, and the rest is modified alumina carrier.

[0113] Comparative Example 4

[0114] The other steps are the same as in Example 1, except that cerium oxide is not added in step (1).

[0115] The weight percentage of each component in the comparative catalyst DC-4 is as follows: 0.25% of Pt, 3.1% of ZSM-5 molecular sieve, and the rest is modified alumina carrier.

[0116] The metal content and noble metal dispersion of the catalysts C-1 to C-8 prepared in the above examples and the catalysts DC-1 to DC-4 prepared in the comparative examples are analyzed, and the results are shown in Table 1.

[0117] Table 1.

[0118]

[0119]

[0120] Example 9

[0121] This example illustrates the olefin hydrogenation reaction performance of the catalyst provided by the present application on reformate.

[0122] The evaluation raw material oil used is reformate provided by a refinery of Sinopec, with a bromine index of 3820 mgBr / 100g and a total aromatic hydrocarbon content of 78%.

[0123] The olefin hydrogenation reaction performance of the catalysts C-1 to C-8 and the comparative examples DC-1 to DC-4 is evaluated by using a 200 mL fixed bed hydrogenation device.

[0124] The evaluation reaction conditions are as follows: operating pressure 2.0 MPa, reaction temperature 170°C, hydrogen / oil volume ratio 200:1, and volume space velocity 10.0 h -1 The evaluation results are shown in Table 2.

[0125] Table 2.

[0126] Catalyst No. Olefin removal, % Aromatic loss, % C-1 86 0.06 C-2 84 0.05 C-3 93 0.07 C-4 86 0.06 C-5 82 0.05 C-6 85 0.05 C-7 95 0.08 C-8 97 0.1 DC-1 53 2.5 DC-2 59 1 DC-3 55 0.5 DC-4 71 0.3

[0127] As can be seen from Table 2, the hydrogenation catalyst of the present application has higher olefin saturation activity and selectivity.

Claims

1. A hydrodeolefinic catalyst, characterized in that, The catalyst uses a mixture of metal oxide and alumina as a carrier, wherein the metal oxide accounts for 3-20% of the total weight of the carrier, and a molecular sieve and an active component are loaded on the carrier; the metal oxide is at least one selected from CeO2, ZrO2 and TiO2, the active component is Pt and / or Pd; the catalyst is characterized by TEM-EDS, and the amount of the molecular sieve directly interacting with the active metal accounts for 60-100% of the total amount of the molecular sieve in terms of the silicon element; the amount of the molecular sieve directly interacting with the active metal refers to the content of the molecular sieve within 2 nm from the outermost layer of the active metal crystal; the molecular sieve accounts for 2-8% of the total weight of the catalyst; the active component accounts for 0.01-0.5% of the total weight of the catalyst in terms of the elementary substance; The molecular sieve is at least one selected from Y-type molecular sieve, ZSM-5 molecular sieve, β-type molecular sieve and MCM-41 molecular sieve; The hydrogenation deolefin catalyst is prepared by the following method: (1) mixing the metal oxide with alumina precursor, extrusion aid and peptizing agent, and performing kneading, molding, drying and calcination to obtain a modified alumina carrier; (2) loading Pt and / or Pd on the modified alumina carrier by impregnation, and performing drying and calcination to obtain a catalyst precursor; an organic aid is added during the impregnation, and the organic aid is at least one selected from ethylene glycol, glycerol, butanediol, pentanediol, acetic acid, citric acid, malonic acid, succinic acid and glutaric acid; (3) introducing the molecular sieve into the catalyst precursor, and then performing drying and calcination; The method for introducing the molecular sieve into the catalyst precursor is performed by at least one of the following ways: (a) performing hydrothermal treatment on the catalyst precursor and the molecular sieve precursor, and then performing the drying and calcination in step (3); (b) mixing the catalyst precursor with the ball-milled molecular sieve in the presence of a solvent, and then performing the drying and calcination in step (3).

2. The hydrodeolefinization catalyst of claim 1, wherein, The amount of the molecular sieve directly interacting with the active metal accounts for 65-95% of the total amount of the molecular sieve in terms of the silicon element.

3. The hydrodeolefinization catalyst of claim 2, wherein, The amount of the molecular sieve directly interacting with the active metal accounts for 70-90% of the total amount of the molecular sieve in terms of the silicon element.

4. The hydrodeolefinization catalyst of claim 3, wherein, The amount of the molecular sieve directly interacting with the active metal accounts for 80-90% of the total amount of the molecular sieve in terms of the silicon element.

5. The hydrodeolefinization catalyst of claim 1, wherein, The molecular sieve accounts for 3-5% of the total weight of the catalyst.

6. The hydrodeolefinization catalyst of claim 1, wherein, The dispersion degree of the active component is 70-100%.

7. A method for preparing the hydrogenation deolefin catalyst according to claim 1, comprising the following steps: (1) mixing the metal oxide with alumina precursor, extrusion aid and peptizing agent, and performing kneading, molding, drying and calcination to obtain a modified alumina carrier; (2) loading Pt and / or Pd on the modified alumina carrier by impregnation, and performing drying and calcination to obtain a catalyst precursor; an organic aid is added during the impregnation, and the organic aid is at least one selected from ethylene glycol, glycerol, butanediol, pentanediol, acetic acid, citric acid, malonic acid, succinic acid and glutaric acid; (3) introducing the molecular sieve into the catalyst precursor, and then performing drying and calcination; The method for introducing the molecular sieve into the catalyst precursor is carried out by at least one of the following ways: (a) hydrothermally treating the catalyst precursor with a molecular sieve precursor, and then carrying out the drying and calcination of step (3); (b) mixing the catalyst precursor with the ball-milled molecular sieve in the presence of a solvent, and then carrying out the drying and calcination of step (3).

8. The production method according to claim 7, characterized by, The precursor of the alumina is selected from one or more of pseudoboehmite, boehmite, gibbsite, nordstrandite and bauxite.

9. The preparation method according to claim 7, characterized in that, The extrusion aid is selected from at least one of starch, polyethylene glycol and sesbania gum, the peptizing agent is selected from at least one of nitric acid, phosphoric acid and acetic acid, the amount of the extrusion aid added is 2-8 wt% of the alumina, the amount of the peptizing agent added is 1-8 wt% of the alumina, and the amount of water added is 50-150 wt% of the alumina.

10. The preparation method according to claim 7, characterized in that, The drying treatment conditions in step (1) are 90-200℃ and 3-6 hours, and the calcination treatment conditions are 500-850℃ and 3-6 hours.

11. The preparation method according to claim 7, characterized in that, The amount of the organic aid added in the impregnation process of step (2) is 3-10 wt% of the carrier alumina.

12. The method of claim 7, wherein, The drying conditions of step (2) are 60-100℃ and 3-6 hours, and the calcination conditions are 200-300℃ and 3-6 hours.

13. The preparation method according to claim 7, characterized in that, The molecular sieve precursor comprises a silicon source or a silicon source and an aluminum source, and is mixed with a precipitator, a template agent and water to form a gel.

14. The method of claim 13, wherein, The silicon source is selected from at least one of sodium silicate, tetraethyl orthosilicate, silica sol and chromatographic silica gel, the aluminum source is selected from at least one of sodium aluminate, aluminum hydroxide and pseudoboehmite, the precipitator is selected from at least one of sodium hydroxide, ammonia and potassium hydroxide, and the template agent is selected from at least one of cetyltrimethylammonium bromide, ethylenediamine, n-butylamine, tetrapropylammonium bromide, ethanol, tetraethylammonium hydroxide, tetraethylammonium bromide, triethylamine, di-n-propylamine, diisopropylamine and methyl cellulose.

15. The method of claim 13, wherein, When the molecular sieve is a silicon-aluminum molecular sieve, the molar composition of the gel is SiO2:Al2O3:Na2O:template agent:H2O=5-30:1:1-10:1-10:100-300, and when the molecular sieve is a full-silicon molecular sieve, the molar composition of the gel is SiO2:Na2O:template agent:H2O=100:10-30:10-30:1500-3000.

16. A method for hydroprocessing a reformed oil product, wherein the oil product is contacted with the hydrodeolefin catalyst of claim 1.

17. The hydroprocessing method of reformed product oil according to claim 16, characterized by, The reaction temperature is 130-280℃, the pressure is 1.0-3.0 MPa, and the volume ratio of hydrogen to oil product is 10-1000.

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