A method for preparing isooctane by hydrogenating isooctene

Abstract

The present invention provides a method for hydrogenating isooctene to isooctane, comprising: contacting isooctene with a molybdenum-nickel-based hydrogenation catalyst, thereby causing a hydrogenation reaction to generate isooctane, wherein the molybdenum-nickel-based hydrogenation catalyst comprises an Al2O3-TiO2 composite oxide and a modifying component and an active component supported on the Al2O3-TiO2 composite oxide, the modifying component comprising cobalt and / or cobalt oxide and cerium and / or cerium oxide, and the active component comprising molybdenum and / or molybdenum oxide and nickel and / or nickel oxide. The present invention uses a non-precious metal catalyst with excellent low-temperature activity and a composite oxide as a carrier, achieves a good hydrogenation effect under low temperature, low pressure and low hydrogen-to-oil ratio, helps to reduce reaction unit energy consumption and operating costs, and the method can effectively avoid sulfur poisoning and chlorine poisoning of the non-precious metal catalyst, and has industrial practical significance.

Description

Technical Field

[0001] The present invention relates to the technical field of petrochemical industry, and in particular to a method for preparing isooctane by hydrogenating isooctene. Background Art

[0002] In 2020, China will fully promote the use of ethanol gasoline. MTBE (methyl tert-butyl ether) will no longer be permitted as a gasoline additive, necessitating the repurposing of significant C4 resources. Indirect alkylation involves the polymerization (dimerization) of C4 olefins to form isooctene, which is then hydrogenated to produce isooctane. Indirect alkylation technology is highly flexible, requires minimal feedstock requirements, and can be retrofitted directly onto MTBE units. The isooctene product, derived from the polymerization of C4 olefins during indirect alkylation, is a high-octane gasoline component with an RON of 105 and a MoN of 95. It can be directly added to gasoline to boost its octane rating, provided olefin content requirements are relaxed. With the improvement of gasoline standards in my country and the introduction of national regulations on olefin content in gasoline, further hydrogenation of isooctene is required to produce isooctane.

[0003] Isooctane is a fuel additive with high octane number, low vapor pressure, no sulfur, no oxygen, no aromatics, and no olefins. Adding isooctane can not only reduce the content of sulfur, olefins, aromatics, etc. in gasoline, but also promote the complete combustion of gasoline and effectively reduce exhaust pollution. Moreover, due to the low vapor pressure of isooctane, it can reduce the unorganized emission of volatile organic compounds during the use, storage and transportation of gasoline.

[0004] The conditions of the hydrogenation reaction are related to the catalyst used. Generally speaking, when using precious metal catalysts such as platinum, palladium, and ruthenium, the reaction can be carried out under mild conditions of a temperature of 100-200°C, a hydrogen partial pressure of 1-2 MPa, and a hydrogen-to-oil ratio of 300-500:1. The hydrogen does not need to be circulated after one pass, and the equipment investment and operating costs are low, but the catalyst is expensive. When using non-precious metal catalysts such as Raneny nickel, amorphous nickel, and supported nickel catalysts, the reaction generally needs to be carried out under harsh conditions of a temperature of 200-350°C, a hydrogen partial pressure of 2-4 MPa, and a hydrogen-to-oil ratio of 500-1,000:1. The hydrogen needs to be recycled, and although the catalyst is cheap, the equipment investment is large, and there are high requirements for the sulfur content of the raw materials. Summary of the Invention

[0005] To address the shortcomings of existing isooctene hydrogenation technologies, the present invention provides a method for producing isooctane by hydrogenating and saturating isooctene. This method utilizes a non-precious metal catalyst with excellent low-temperature activity supported by a composite oxide, achieving excellent hydrogenation results at low temperatures, low pressures, and a low hydrogen-to-oil ratio. This helps reduce reactor energy consumption and operating costs, and effectively avoids sulfur and chlorine poisoning of the non-precious metal catalyst, thus having practical industrial significance.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A method for hydrogenating isooctene to isooctane comprises: contacting isooctene with a molybdenum-nickel-based hydrogenation catalyst, thereby causing a hydrogenation reaction to produce isooctane, wherein the molybdenum-nickel-based hydrogenation catalyst comprises an Al2O3-TiO2 composite oxide and a modifying component and an active component supported on the Al2O3-TiO2 composite oxide, the modifying component comprising cobalt and / or cobalt oxide and cerium and / or cerium oxide, and the active component comprising molybdenum and / or molybdenum oxide and nickel and / or nickel oxide.

[0008] In some preferred embodiments of the present invention, the molybdenum-nickel-based hydrogenation catalyst is prepared by first loading the modifying component on the Al2O3-TiO2 composite oxide, and then loading the active component.

[0009] In some preferred embodiments of the present invention, when loading the active component, the molybdenum element is loaded first and then the nickel element is loaded.

[0010] In some preferred embodiments of the present invention, the contacting is carried out in a reactor, and the operating conditions of the reactor include: an inlet temperature of 90°C to 180°C, preferably 100°C to 140°C; a pressure of 2.0 MPa to 7.0 MPa, preferably 2.5 MPa to 3.5 MPa; a hydrogen-to-oil ratio of 200:1 to 600:1, preferably 400 to 500:1; a circulation ratio of 0 to 4:1, preferably 2:1 to 3:1; a volume space velocity of 0.5 h -1 ~2.0h -1 , preferably 1.0h -1 ~1.5h -1 .

[0011] In the present invention, the term "hydrogen-to-oil ratio" refers to the volume ratio of hydrogen to fresh raw material isooctene.

[0012] In the present invention, the term "fresh feedstock" refers to newly added isooctene.

[0013] In the present invention, the term "circulation ratio" refers to the volume ratio of recycled material to fresh raw material.

[0014] In the present invention, the outlet temperature is determined by the inlet temperature and the circulation ratio. When the operating conditions such as the inlet temperature and the circulation ratio are determined, the outlet temperature is also determined. Therefore, the outlet temperature is not limited in the present invention.

[0015] In some preferred embodiments of the present invention, the content of diene in the isooctene is not higher than 1 wt %.

[0016] In some preferred embodiments of the present invention, based on the total mass of the Al2O3-TiO2 composite oxide, the content of Al2O3 is 70wt% to 90wt%; and the content of TiO2 is 10wt% to 30wt%.

[0017] In some preferred embodiments of the present invention, based on the total mass of the Al2O3-TiO2 composite oxide, the content of Al2O3 is 70wt% to 80wt%; and the content of TiO2 is 20wt% to 30wt%.

[0018] According to the present invention, the shape of the Al2O3-TiO2 composite oxide is selected from one or more of granular, spherical, gear-shaped, blade-shaped, strip-shaped or clover-shaped, preferably clover-shaped.

[0019] According to the present invention, the Al2O3-TiO2 composite oxide can be obtained through commercial channels or prepared by a homemade method. For example, the preparation method of the Al2O3-TiO2 composite oxide is:

[0020] a) mixing an aluminum-containing solution, a titanium-containing solution and an alkaline solution, and co-precipitating to obtain a precipitate;

[0021] b) drying and calcining the precipitate to obtain the Al2O3-TiO2 composite oxide.

[0022] According to the present invention, in step a), the flow rate of the alkaline solution is controlled so that the pH of the precipitate is maintained in the range of 5.0-6.0 for 5-10 minutes, preferably 8 minutes, and then the flow rate of the alkaline solution is increased so that the pH value of the mixed solution is maintained in the range of 8.5-9.5 for 5-10 minutes, preferably 8 minutes. Then, the flow rate of the alkaline solution is reduced so that the pH value of the mixed solution is maintained in the range of 5.0-6.0 for 5-10 minutes, preferably 8 minutes, and then the flow rate of the alkaline solution is increased so that the pH value of the precipitate is within the range of 8.5-9.5. This process is repeated until the aluminum-containing solution and the titanium-containing solution are completely added.

[0023] According to the present invention, in step a), the aluminum-containing solution may be a solution prepared by dissolving a soluble aluminum salt in water; and the titanium-containing solution may be a solution prepared by dissolving a soluble titanium salt in benzene. The soluble aluminum salt may be aluminum sulfate, aluminum nitrate, or aluminum chloride, and the soluble titanium salt may be Ti(OCH2CH3)4.

[0024] According to the present invention, in step b), the alkaline solution can be a mixed solution of NH4HCO3, ammoniacal liquor and water. Wherein, the ammoniacal liquor is a concentrated ammoniacal liquor with a concentration of 25wt% to 28wt%. In a specific embodiment, 10-30g of NH4HCO3 (analytical grade) is dissolved in 600mL of deionized water, followed by adding 200mL to 300mL of ammoniacal liquor with a concentration of 25wt% to 28wt%, stirring evenly, and then adding a certain volume of deionized water to make 1000mL of alkaline solution.

[0025] According to the present invention, in step b), the drying conditions may be: temperature of 90°C to 150°C, time of 1 hour to 24 hours; the calcination conditions may be: temperature of 350°C to 550°C, time of 1 hour to 24 hours.

[0026] According to the present invention, the precipitate may be filtered and washed before drying. Filtering and washing are conventional operations in the art and will not be described in detail here.

[0027] In some other embodiments of the present invention, the Al2O3-TiO2 composite oxide is preferably a titanium oxide-aluminum oxide composite support provided in patent CN104971706B.

[0028] In some preferred embodiments of the present invention, based on the total mass of the molybdenum-nickel-based hydrogenation catalyst, the content of cobalt and / or cobalt oxide is 0.5wt% to 2wt%; the content of cerium and / or cerium oxide is 1wt% to 3wt%; the content of molybdenum and / or molybdenum oxide is 8wt% to 20wt%; and the content of nickel and / or nickel oxide is 4wt% to 12wt%.

[0029] In some preferred embodiments of the present invention, the specific surface area of ​​the molybdenum-nickel based hydrogenation catalyst is 150 m 2 / g~300m 2 / g; pore volume is 0.3mL / g~0.6mL / g.

[0030] In some preferred embodiments of the present invention, the modifying component further comprises calcium and / or calcium oxides, and the content of calcium and / or calcium oxides is 0.1 wt% to 3.0 wt% based on the total mass of the hydrorefining catalyst.

[0031] In some preferred embodiments of the present invention, the method for preparing the molybdenum-nickel-based hydrogenation catalyst comprises:

[0032] S1 using an impregnation solution containing cobalt and cerium elements to impregnate the Al2O3-TiO2 composite oxide, and the impregnation product was dried and calcined to obtain a surface-modified Al2O3-TiO2 composite oxide;

[0033] S2 using an impregnation solution containing molybdenum element on the surface-modified Al2O3-TiO2 composite oxide was impregnated, and the impregnation product was dried and calcined to obtain a catalyst precursor;

[0034] S3. The catalyst precursor is impregnated with an impregnation solution containing nickel, and the impregnation product is dried and calcined to obtain the hydrorefining catalyst.

[0035] In some preferred embodiments of the present invention, the impregnation solution containing cobalt and cerium elements further contains calcium element.

[0036] In some preferred embodiments of the present invention, in step S1, the calcination treatment conditions include a temperature of 450°C to 650°C, preferably 500°C to 600°C; and a time of 1 hour to 24 hours, preferably 2 hours to 12 hours.

[0037] In some preferred embodiments of the present invention, in step S2, the calcination treatment conditions include a temperature of 450°C to 650°C, preferably 500°C to 600°C; and a time of 1 hour to 24 hours, preferably 2 hours to 12 hours.

[0038] In some preferred embodiments of the present invention, in step S3, the calcination treatment conditions include a temperature of 450°C to 650°C, preferably 500°C to 600°C; and a time of 1 hour to 24 hours, preferably 2 hours to 12 hours.

[0039] According to the present invention, in the above preparation method, the amount of each substance used must satisfy the requirement that the content of each component of the prepared hydrotreating catalyst is within the range defined in any of the above embodiments.

[0040] According to the present invention, the molybdenum nickel-based hydrogenation catalyst may be subjected to a sulfurization treatment before the hydrogenation reaction. Sulfidation treatment is a conventional pretreatment method in the art, and the present invention is not intended to impose too much limitation on this. For example, the sulfurization treatment comprises: heating the catalyst at a hydrogen pressure of 2.0-3.5 MPa, a hydrogen-to-oil ratio of 300-500:1, and a temperature of 300-350°C for 2-5 hours. -1 The sulfurized oil containing dimethyl disulfide (DMDS) is introduced at a logistics volume space velocity of 10-30h.

[0041] According to the present invention, the hydrogen-to-oil ratio involved in the sulfurization treatment refers to the volume ratio of hydrogen gas to sulfurized oil.

[0042] According to the present invention, the sulfidation treatment can improve the hydrogenation activity of the catalyst.

[0043] The beneficial effects of the present invention are at least in the following aspects:

[0044] First, the method for hydrogenating and saturating isooctene provided by the present invention uses a molybdenum-nickel-based catalyst with good low-temperature activity to hydrogenate isooctene at a lower inlet temperature, thereby reducing the content of unsaturated hydrocarbons in the raw material and increasing the added value of the product. The catalyst has strong impurity resistance and can improve operational stability.

[0045] Secondly, by controlling the reactor inlet temperature at a lower level, the present invention avoids the process problems caused by the vaporization of the C4 fraction under high temperature conditions, reduces energy consumption, and easily achieves the device operating conditions, which has good operability. In addition, the inventors found that compared with the minimum reactor inlet temperature of 200-300°C reported in the literature for isooctenes hydrogenation using non-precious metal catalysts such as Raneny nickel, amorphous nickel, and supported nickel catalysts, the molybdenum-nickel-based hydrorefining catalyst using an alumina-titania composite support can reduce the reactor startup temperature to 100°C for startup, thereby avoiding the process problems caused by the vaporization of the C4 fraction under high temperature conditions, reducing energy consumption, and the catalyst has a high resistance to impurities (such as sulfides, nitrides, and chlorine), which can ensure the long-term stable operation of the catalyst.

[0046] Thirdly, the hydrogenation method of the present invention can process isooctene obtained by polymerization of low C4 olefins, and the monoolefin content of the isooctene stream after hydrogenation can be less than 1 wt%. DETAILED DESCRIPTION

[0047] The present invention is described in detail below through examples, but the protection scope of the present invention is not limited to the following description.

[0048] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or those recommended by the manufacturer. All reagents or instruments used, if the manufacturer is not specified, are conventional products that can be obtained through commercial channels.

[0049] In the following embodiments, unless otherwise specified, the components of the hydrogenated material are analyzed after the device has been running for 96 hours.

[0050] In the following embodiments, unless otherwise specified, the content of each substance in the hydrogenation product is detected by gas chromatography.

[0051] In the following embodiments, unless otherwise specified, the content of active components in the catalyst is detected by X-ray fluorescence (XRF) analysis.

[0052] Example 1

[0053] A. Preparation of Hydrorefining Catalyst

[0054] a) Preparation of Al2O3 / TiO2 composite oxide support

[0055] Solution A1 was prepared by placing 178.5 g of AlCl3·6H2O (analytical grade) in 1000 mL of deionized water; solution B1 was prepared by dissolving 430.7 g of Ti(OCH2CH3)4 (chemical grade) in 500 mL of benzene (benzene content: 99.8 wt%); and solution C1 was prepared by dissolving 18 g of NH4HCO3 (analytical grade) in 600 mL of deionized water, followed by the addition of 250 mL of 26 wt% aqueous ammonia, stirring uniformly, and adding a certain volume of deionized water to prepare 1000 mL of solution C1.

[0056] Under normal pressure and a temperature of 73°C, solutions A1, B1, and C1 were co-precipitated in parallel. The flow rate of solution C1 was controlled to maintain the pH value of the precipitate within the range of 5.0-6.0 for 8 minutes. The flow rate of solution C1 was then increased to maintain the pH value of the mixed solution within the range of 8.5-9.5 for 8 minutes. The flow rate of solution C1 was then reduced to maintain the pH value of the mixed solution within the range of 5.0-6.0 for 8 minutes. The flow rate of solution C1 was then increased to maintain the pH value of the precipitate within the range of 8.5-9.5. This process was repeated until all solutions A1 and B1 were added dropwise to obtain a reaction solution.

[0057] The resulting reaction solution was allowed to stand at 70°C for 30 minutes before being filtered to produce a filter cake. The filter cake was then washed with deionized water (15 times the volume of the filter cake) for 30 minutes, filtered again, and washed again. This process was repeated four times. Finally, the filter cake was dried at 110°C for 10 hours and calcined at 450°C for 5 hours to produce 42.7 g of an Al2O3-TiO2 composite oxide support (designated Z1). The TiO2 content was 15.14%, with the remainder being Al2O3.

[0058] b) Modification of the support surface

[0059] A mixed solution of cobalt nitrate and cerium nitrate was prepared in a volumetric flask and impregnated with 100 g of the support Z1 prepared in step a) at room temperature for 2 hours. After filtration, the solution was dried at 110°C for 4 hours and calcined at 550°C for 4 hours to complete the modification of support Z1. The modified support was designated Z2. The cobalt oxide content of support Z2 was 1.2 wt% and the cerium oxide content was 1.5 wt%.

[0060] c) Loading of active ingredients

[0061] Use a volumetric flask and 14 wt% ammonia water to prepare 26.68 g / 100 mL of ammonium molybdate tetrahydrate, and impregnate 100 g of the carrier Z2 prepared in step b) at room temperature for 2 hours. After filtering, dry it at 110°C overnight and calcine it at 550°C for 4 hours to complete the loading of the active component molybdenum oxide to obtain the catalyst precursor Z3.

[0062] Then, the catalyst precursor Z3 loaded with molybdenum oxide was placed in 39.48 g / 100 mL of nickel nitrate hexahydrate, soaked at room temperature for 2 hours, filtered, dried at 110°C overnight, and calcined at 550°C for 4 hours to obtain MoO3-CoO / Al2O3-TiO2 catalyst A with a MoO3 content of 14.1 wt% and a NiO content of 7.5 wt%.

[0063] B. Hydrogenation reaction

[0064] A 100 mL fixed-bed reactor was loaded with 100 mL of hydrogenation catalyst A to carry out the sulfidation reaction. The sulfidation conditions were: hydrogen pressure 2.0 MPa, hydrogen-to-oil ratio 300-500:1, and temperature 300°C. The reaction was continued for 2 h. -1 Sulfurized oil containing 3 wt% of dimethyl disulfide (DMDS) was introduced for 15 h at a log volume space velocity of .

[0065] After the sulfidation reaction, the hydrogenation reaction was carried out. The operating conditions of the hydrogenation reactor were: inlet temperature of 140 ° C, pressure of 3.5 MPa, oil-gas ratio of 600:1, and volume space velocity of isooctene raw material of 0.8h -1 , the circulation ratio is 2:1.

[0066] The product composition at the reactor outlet was as follows: the octene content was 0.18 wt%, and the balance was alkanes.

[0067] Example 2

[0068] A. Preparation of Hydrorefining Catalyst

[0069] a) Preparation of Al2O3 / TiO2 composite oxide support

[0070] The amount of titanium salt added was adjusted, and the method of Example 1 was used to prepare a composite oxide support (named Z1) with a TiO2 content of 25 wt% and the balance being Al2O3.

[0071] b) Modification of the support surface

[0072] The addition amounts of cobalt nitrate and cerium nitrate were adjusted, and the method of Example 1 was used to prepare a modified support having a cobalt oxide content of 0.83 wt % and a cerium oxide content of 1.90 wt %, which was recorded as Z2.

[0073] c) Loading of active ingredients

[0074] The addition amounts of ammonium molybdate tetrahydrate and nickel nitrate hexahydrate were adjusted, and the method of Example 1 was used to prepare MoO3-CoO / Al2O3-TiO2 catalyst B with a MoO3 content of 12wt% and a NiO content of 11wt%.

[0075] B. Hydrogenation reaction

[0076] A 100 mL fixed-bed reactor was loaded with 100 mL of hydrogenation catalyst A to carry out the sulfidation reaction. The sulfidation conditions were: hydrogen pressure 2.0 MPa, hydrogen-to-oil ratio 300-500:1, and temperature 300°C. The reaction was continued for 2 h. -1 Sulfurized oil containing 3 wt% of dimethyl disulfide (DMDS) was introduced for 15 h at a log volume space velocity of .

[0077] After the sulfidation reaction, the hydrogenation reaction was carried out. The operating conditions of the hydrogenation reactor were: inlet temperature of 100 ° C, pressure of 2.5 MPa, oil-gas ratio of 500:1, and volume space velocity of isooctene raw material of 2h -1 , the circulation ratio is 3:1.

[0078] The product composition at the reactor outlet is as follows: the octene content is 0.23 wt%, and the balance is alkanes.

[0079] Example 3

[0080] A. Preparation of Hydrorefining Catalyst

[0081] a) Preparation of Al2O3 / TiO2 composite oxide support

[0082] The composite oxide support of Example 1 (designated as Z1) was used.

[0083] b) Modification of the support surface

[0084] The addition amounts of cobalt nitrate and cerium nitrate were adjusted, and the method of Example 1 was used to prepare a modified support having a cobalt oxide content of 0.58 wt % and a cerium oxide content of 0.76 wt %, which was recorded as Z2.

[0085] c) Loading of active ingredients

[0086] The addition amounts of ammonium molybdate tetrahydrate and nickel nitrate hexahydrate were adjusted, and the method of Example 1 was used to prepare MoO3-CoO / Al2O3-TiO2 catalyst C with a MoO3 content of 11 wt% and a NiO content of 9.5 wt%.

[0087] B. Hydrogenation reaction

[0088] A 100 mL fixed-bed reactor was loaded with 100 mL of hydrogenation catalyst A to carry out the sulfidation reaction. The sulfidation conditions were: hydrogen pressure 2.0 MPa, hydrogen-to-oil ratio 300-500:1, and temperature 300°C. The reaction was continued for 2 h. -1 Sulfurized oil containing 3 wt% of dimethyl disulfide (DMDS) was introduced for 15 h at a log volume space velocity of .

[0089] After the sulfidation reaction, the hydrogenation reaction was carried out. The operating conditions of the hydrogenation reactor were: inlet temperature of 120 ° C, pressure of 2.8 MPa, oil-gas ratio of 400:1, and volumetric space velocity of isooctene raw material of 1.5h -1 , the circulation ratio is 2:1.

[0090] The product composition at the reactor outlet is as follows: the octene content is 0.05 wt%, and the balance is alkanes.

[0091] Example 4

[0092] A. Preparation of Hydrorefining Catalyst

[0093] a) Preparation of Al2O3 / TiO2 composite oxide support

[0094] The composite oxide support of Example 1 (designated as Z1) was used.

[0095] b) Modification of the support surface

[0096] The support was impregnated with a mixed solution of cobalt nitrate, cerium nitrate, and calcium nitrate, dried, and calcined in the same manner as in Example 1. The modified support was designated Z2. The Z2 support contained 0.53 wt% cobalt oxide, 1.08 wt% cerium oxide, and 0.59 wt% calcium oxide.

[0097] c) Loading of active ingredients

[0098] The method is the same as that of Example 1. A MoO3-CoO / Al2O3-TiO2 catalyst D having a MoO3 content of 14.1 wt% and a NiO content of 7.5 wt% is obtained.

[0099] The specific surface area of ​​catalyst D was 265m 2 / g; pore volume is 0.35mL / g.

[0100] B. Hydrogenation reaction

[0101] The hydrogenation method is exactly the same as that in Example 1. The composition of the product at the outlet of the reactor using catalyst D is as follows: the octene content is 0.09 wt%, and the balance is alkanes.

[0102] Example 5

[0103] A. Preparation of Hydrorefining Catalyst

[0104] a) Preparation of Al2O3 / TiO2 composite oxide support

[0105] The composite oxide support of Example 1 (designated as Z1) was used.

[0106] b) Modification of the support surface

[0107] A cobalt nitrate solution was prepared in a volumetric flask, and 100 g of the carrier Z1 prepared in step a) was impregnated at room temperature for 2 hours. After filtering, the solution was dried at 110°C for 4 hours and calcined at 550°C for 4 hours to complete the preliminary modification of the carrier Z1. The carrier after preliminary modification was designated as Z2.

[0108] A cerium nitrate solution was prepared in a volumetric flask, and 100 g of the carrier Z2 prepared in step a) was impregnated at room temperature for 2 hours. After filtration, the solution was dried at 110°C for 4 hours and calcined at 550°C for 4 hours to complete the modification of the carrier Z2. The modified carrier was designated as Z3.

[0109] c) Loading of active ingredients

[0110] The method is the same as that of Example 1. A catalyst F of MoO3-CoO / Al2O3-TiO2 having a MoO3 content of 14.1 wt% and a NiO content of 7.5 wt% is obtained.

[0111] B. Hydrogenation reaction

[0112] The hydrogenation method is exactly the same as that in Example 1. When Catalyst F is used, the composition of the product at the reactor outlet is: octene content is 0.18 wt%, and the balance is alkanes.

[0113] Example 6

[0114] A. Preparation of Hydrorefining Catalyst

[0115] a) Preparation of Al2O3 / TiO2 composite oxide support

[0116] The composite oxide support of Example 1 (designated as Z1) was used.

[0117] b) Modification of the support surface

[0118] A cerium nitrate solution was prepared in a volumetric flask, and 100 g of the carrier Z1 obtained in step a) was impregnated at room temperature for 2 hours. After filtering, the solution was dried at 110°C for 4 hours and calcined at 550°C for 4 hours to complete the preliminary modification of the carrier Z1. The carrier after preliminary modification was designated as Z2.

[0119] A cobalt nitrate solution was prepared in a volumetric flask, and 100 g of the carrier Z2 prepared in step a) was impregnated at room temperature for 2 hours. After filtering, the solution was dried at 110°C for 4 hours and calcined at 550°C for 4 hours to complete the modification of the carrier Z2. The modified carrier was designated as Z3.

[0120] c) Loading of active ingredients

[0121] The method is the same as that of Example 1. A MoO3-CoO / Al2O3-TiO2 catalyst G with a MoO3 content of 14.1 wt% and a NiO content of 7.5 wt% is obtained.

[0122] B. Hydrogenation reaction

[0123] The hydrogenation method is exactly the same as that in Example 1. When Catalyst G is used, the product composition at the reactor outlet is: octene content is 0.16 wt%, and the balance is alkanes.

[0124] Comparative Example 1

[0125] A. Preparation of Hydrorefining Catalyst

[0126] a) Preparation of Al2O3 / TiO2 composite oxide support

[0127] The composite oxide support of Example 1 (designated as Z1) was used.

[0128] b) Loading of active ingredients

[0129] According to step c) of Example 1, active components were loaded on the carrier Z1 to prepare a MoO3-CoO / Al2O3-TiO2 catalyst a having a MoO3 content of 14.1 wt% and a NiO content of 7.5 wt%.

[0130] B. Hydrogenation reaction

[0131] The hydrogenation method is exactly the same as that in Example 1. When Catalyst I is used, the composition of the product at the reactor outlet is as follows: the octene content is 6.23 wt%, and the balance is alkanes.

[0132] Comparative Example 2

[0133] A. Preparation of Hydrorefining Catalyst

[0134] a) Preparation of Al2O3 / TiO2 composite oxide support

[0135] The composite oxide support of Example 1 (designated as Z1) was used.

[0136] b) Modification of the support surface

[0137] A cerium nitrate solution was prepared in a volumetric flask and impregnated with 100 g of the support Z1 prepared in step a) at room temperature for 2 hours. After filtration, the solution was dried at 110°C for 4 hours and calcined at 550°C for 4 hours to complete the modification of support Z1. The modified support was designated Z2. The cerium oxide content in support Z2 was 2.7 wt%.

[0138] c) Loading of active ingredients

[0139] Active components were loaded on carrier Z2 in the manner of Example 1 to prepare MoO3-CoO / Al2O3-TiO2 catalyst b with a MoO3 content of 14.1 wt% and a NiO content of 7.5 wt%.

[0140] B. Hydrogenation reaction

[0141] The hydrogenation method is exactly the same as that in Example 1. When catalyst b is used, the product composition at the reactor outlet is: octene content is 4.86 wt%, and the balance is alkanes.

[0142] Comparative Example 3

[0143] A. Preparation of Hydrorefining Catalyst

[0144] a) Preparation of Al2O3 / TiO2 composite oxide support

[0145] The composite oxide support of Example 1 (designated as Z1) was used.

[0146] b) Modification of the support surface

[0147] A cobalt nitrate solution was prepared in a volumetric flask and impregnated with 100 g of the support Z1 prepared in step a) at room temperature for 2 hours. After filtration, the solution was dried at 110°C for 4 hours and calcined at 550°C for 4 hours to complete the modification of support Z1. The modified support was designated Z2. The cobalt oxide content in support Z2 was 2.7 wt%.

[0148] c) Loading of active ingredients

[0149] Active components were loaded on carrier Z2 in the manner of Example 1 to prepare MoO3-CoO / Al2O3-TiO2 catalyst c with a MoO3 content of 14.1 wt% and a NiO content of 7.5 wt%.

[0150] B. Hydrogenation reaction

[0151] The hydrogenation method is exactly the same as that in Example 1. When catalyst C is used, the product composition at the reactor outlet is: octene content is 3.99 wt%, and the balance is alkanes.

[0152] Comparative Example 4

[0153] A. Preparation of Hydrorefining Catalyst

[0154] a) Preparation of Al2O3 / TiO2 composite oxide support

[0155] The composite oxide support of Example 1 (designated as Z1) was used.

[0156] b) Modification of the support surface

[0157] Lanthanum nitrate was used instead of cerium nitrate in step b) of Example 1, and the other conditions were the same to prepare a modified support, denoted as Z2. The cobalt oxide content in Z2 support was 1.2 wt% and the lanthanum oxide content was 1.5 wt%.

[0158] c) Loading of active ingredients

[0159] Active components were loaded on carrier Z2 in the manner of Example 1 to prepare MoO3-CoO / Al2O3-TiO2 catalyst d having a MoO3 content of 14.1 wt% and a NiO content of 7.5 wt%.

[0160] B. Hydrogenation reaction

[0161] The hydrogenation method is exactly the same as that in Example 1. When catalyst d is used, the composition of the product at the reactor outlet is: octene content is 3.79 wt%, and the balance is alkanes.

[0162] Comparative Example 5

[0163] A. Preparation of Hydrorefining Catalyst

[0164] a) The spherical γ-Al2O3 carrier in CN104437451A is used.

[0165] b) Modification of the support surface

[0166] Same as Example 1.

[0167] c) Loading of active ingredients

[0168] The same as Example 1. A MoO3-CoO / Al2O3 catalyst e was prepared with a MoO3 content of 14.1 wt% and a NiO content of 7.5 wt%.

[0169] B. Hydrogenation reaction

[0170] The hydrogenation method is exactly the same as that in Example 1. When catalyst e is used, the product composition at the reactor outlet is: octene content is 19.6 wt%, and the balance is alkanes.

[0171] It should be noted that the embodiments described above are only used to explain the present invention and do not constitute any limitation of the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein. On the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A method for preparing isooctane by hydrogenating isooctene, comprising: isooctene is contacted with a molybdenum-nickel-based hydrogenation catalyst, thereby undergoing a hydrogenation reaction to produce isooctane, wherein the molybdenum-nickel-based hydrogenation catalyst comprises an Al2O3-TiO2 composite oxide and a modifying component and an active component supported on the Al2O3-TiO2 composite oxide, the modifying component comprising cobalt and / or cobalt oxide and cerium and / or cerium oxide, and the active component comprising molybdenum and / or molybdenum oxide and nickel and / or nickel oxide; The contact is carried out in a reactor, and the operating conditions of the reactor include: an inlet temperature of 90° C. to 180° C., a pressure of 2.0 MPa to 7.0 MPa, and a hydrogen-to-oil ratio of 200:1 to 600:

1.

2. The method according to claim 1, characterized in that The molybdenum-nickel based hydrogenation catalyst is prepared by first loading the modified component on the Al2O3-TiO2 composite oxide and then loading the active component.

3. The method according to claim 1, characterized in that When the active component is loaded, the molybdenum element is loaded first and then the nickel element is loaded.

4. The method according to claim 1, wherein The operating conditions of the reactor also include: a circulation ratio of 0 to 4:1; a volume space velocity of 0.5 h -1 ~2.0h -1 .

5. The method according to claim 1, wherein The operating conditions of the reactor include: an inlet temperature of 100°C to 140°C; and / or a pressure of 2.5 MPa to 3.5 MPa; and / or a hydrogen-to-oil ratio of 400 to 500:1; and / or a circulation ratio of 2:1 to 3:1; and / or a volume space velocity of 1.0 h -1 ~1.5h -1 .

6. The method according to claim 1, characterized in that The content of diene in the isooctene is not higher than 1 wt %.

7. The method according to any one of claims 1 to 6, characterized in that Based on the total mass of the Al2O3-TiO2 composite oxide, the content of Al2O3 is 70wt%~90wt%; the content of TiO2 is 10wt%~30wt%.

8. The method according to any one of claims 1 to 6, characterized in that Based on the total mass of the molybdenum-nickel-based hydrogenation catalyst, the content of cobalt and / or cobalt oxide is 0.5wt%~2wt%; the content of cerium and / or cerium oxide is 1wt%~3wt%; the content of molybdenum and / or molybdenum oxide is 8wt%~20wt%; and the content of nickel and / or nickel oxide is 4wt%~12wt%.

9. The method according to any one of claims 1 to 6, characterized in that The specific surface area of ​​the molybdenum-nickel based hydrogenation catalyst is 150 m 2 / g~300m 2 / g; pore volume is 0.3mL / g~0.6mL / g.

10. The method according to any one of claims 1 to 6, characterized in that The preparation method of the molybdenum-nickel based hydrogenation catalyst comprises: S1 using an impregnation solution containing cobalt and cerium elements to impregnate the Al2O3-TiO2 composite oxide, and the impregnation product was dried and calcined to obtain a surface-modified Al2O3-TiO2 composite oxide; S2 using an impregnation solution containing molybdenum element on the surface-modified Al2O3-TiO2 composite oxide was impregnated, and the impregnation product was dried and calcined to obtain a catalyst precursor; S3. Impregnating the catalyst precursor with an impregnation solution containing nickel, and drying and calcining the impregnation product to obtain the hydrorefining catalyst.

11. The method according to claim 10, characterized in that In step S1, the calcination treatment conditions include a temperature of 450° C. to 650° C. and a time of 1 hour to 24 hours.

12. The method according to claim 11, characterized in that In step S1, the calcination treatment conditions include a temperature of 500° C. to 600° C.; and / or a calcination time of 2 h to 12 h.

13. The method according to claim 10, characterized in that In step S2, the calcination treatment conditions include a temperature of 450° C. to 650° C. and a time of 1 hour to 24 hours.

14. The method according to claim 13, characterized in that In step S2, the calcination treatment conditions include a temperature of 500° C. to 600° C. and a time of 2 h to 12 h.

15. The method according to claim 10, characterized in that In step S3, the calcination treatment conditions include a temperature of 450° C. to 650° C. and a time of 1 hour to 24 hours.

16. The method according to claim 15, characterized in that In step S3, the calcination treatment conditions include a temperature of 500° C. to 600° C. and a time of 2 h to 12 h.