A catalyst for the synthesis of lubricating oil base stocks and a method for its preparation

Abstract

The application provides a catalyst for lubricating oil base oil synthesis and a preparation method thereof, and selects a heteroatom Y zeolite with high mesopore, small crystal grain and high silicon-aluminum ratio as a modified precursor, adopts rare earth ion exchange and equal-volume impregnation of diammonium hydrogen phosphate to modify the heteroatom Y zeolite, the prepared solid acid catalyst has the advantages of not easy to accumulate carbon, high hydrothermal stability, easy regeneration, high selectivity and the like, the synthesized alkyl naphthalene is all single-substituted alkyl naphthalene, and alpha-alkyl naphthalene / beta-alkyl naphthalene is at least 1.5, so that the synthesized alkyl naphthalene has excellent thermal oxygen stability, can be used as lubricating oil base oil alone, and can be used as an additive of other lubricating oils to improve the thermal oxygen stability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of synthetic lubricating oil base oil, and particularly relates to a catalyst for synthesizing lubricating oil base oil and a preparation method thereof. BACKGROUND

[0002] Mineral base oil is widely used in the field of lubricating oil, which accounts for 95% of the lubricating oil market in China. However, because of its poor thermal stability and oxidation stability, it cannot meet the requirements of the high-end lubricating oil market. Synthetic base oil is a good supplement to the lubricating oil market. Common synthetic base oils include polyalphaolefin (PAO) of the fourth type of lubricating oil and alkyl naphthalene of the fifth type of lubricating oil. Compared with mineral base oil, synthetic base oil has better low-temperature fluidity, higher oxidation stability, thermal stability, lower evaporation loss rate and good additive solubility. As the fifth type of lubricating oil, alkyl naphthalene base oil has more outstanding oxidation stability and additive solubility advantages compared with other synthetic base oils. Alkyl naphthalene has broad application prospects and can be used as a base oil alone or as an additive for mineral oil base oil and other synthetic base oils, mainly for high-end lubricating oil and lubricating grease.

[0003] Long-chain alkyl naphthalene is mainly synthesized by Friedel-Crafts reaction of naphthalene and long-chain α-olefins. Commonly used catalysts include inorganic acid catalysts and Lewis acid catalysts.

[0004] Long-chain alkyl naphthalene is mainly prepared by alkylation of naphthalene. Commonly used alkylating agents include long-chain α-olefins, halogenated alkanes and alcohols. The use of long-chain α-olefins as an alkylating agent results in more excellent properties of the base oil product. Commonly used alkylation catalysts include inorganic acids (concentrated sulfuric acid, HF, etc.), Lewis acids (AlCl3, ZnCl2, FeCl3, etc.). These catalysts all have problems such as corrosion of equipment, serious environmental pollution and difficulty in separating the product from the raw material.

[0005] US4714794 describes that monosubstituted alkyl naphthalene has excellent thermal oxygen stability, low vapor pressure and low flash point, good low-temperature fluidity and high heat transfer capacity, and is very suitable for use as a lubricating oil base oil. US4604491, US4211665 and US4238343 describe that a mixture of monosubstituted alkyl naphthalene and polysubstituted alkyl naphthalene is used as a lubricating oil base oil. The most preferred alkyl naphthalene is monosubstituted alkyl naphthalene, which has the best performance, such as better thermal stability and oxidation stability than polysubstituted alkyl naphthalene, and thus can be used as a more excellent lubricating oil base oil or additive. Too high or too low viscosity of lubricating oil will increase the wear between mechanical devices, and the monosubstituted alkyl naphthalene has a C 14 ~C 18The monosubstituted alkyl naphthalene has a kinematic viscosity of 5-8 cst at 100°C, and the kinematic viscosity is in the optimal range. The currently used alkylating catalysts have poor selectivity, and cannot synthesize long-chain monosubstituted alkyl naphthalene with high selectivity.

[0006] US4604491 uses active silica-alumina clay as an alkylating catalyst to prepare long-chain alkyl naphthalene by alkylating naphthalene with alpha-olefins (mono-olefins or mixed olefins), which needs to be reacted at 200°C for 6 hours, the reaction time is too long, the reaction temperature is too high, the energy consumption is large, and the product separation is difficult. At present, there are many aspects to be improved for solid acid catalysts, such as the pore channels of the molecular sieve are easily blocked by the by-product of olefin polymerization, which causes the catalyst to be deactivated, the product has a deep color, the preparation of the modified solid acid catalyst is complicated, and the service life of the catalyst is insufficient. Chinese patent CN1029611C uses supported heteropoly acid and its salt as an alkylating catalyst, which needs to be carried out in a pressurized closed container, which has high requirements for the reaction equipment and harsh reaction conditions. Chinese patent CN20151085128 uses gallium triflate as an alkylating catalyst, and the performance of alkyl naphthalene base oil is investigated, but the preparation of gallium triflate catalyst is expensive, and the catalyst contains fluorine element which pollutes the environment. Chinese patent CN102965175A uses methanesulfonic acid as a catalyst, which needs to be treated by alkaline washing and decolorization, and the reaction process is complex and pollutes the environment, so the synthesis process of alkyl naphthalene and the property analysis and characterization of alkyl naphthalene base oil also need to be greatly improved. SUMMARY

[0007] The present application develops a modified Y molecular sieve alkylating catalyst doped with heteroatoms, rare earth metals and loaded with phosphorus to solve the problems of corrosion of inorganic acid catalysts, poor separation of products, pollution of the environment, easy deactivation of solid acid catalysts, short service life, poor activity after regeneration, and inability to synthesize monosubstituted long-chain alkyl naphthalene with high selectivity, and adjusts the synthesis process of alkyl naphthalene to synthesize monosubstituted long-chain alkyl naphthalene base oil with more outstanding oxidation stability.

[0008] The synthesized base oil product is all monosubstituted alkyl naphthalene, that is, the alkyl naphthalene contains one same C4-C 22 alkyl substituent group, and the alpha-alkyl naphthalene / beta-alkyl naphthalene in the product is at least 1.5.

[0009] To achieve the above-mentioned purpose, the technical scheme is adopted as follows:

[0010] The present application develops a modified Y molecular sieve alkylating catalyst doped with heteroatoms, rare earth metals and loaded with phosphorus, and the preparation method is as follows:

[0011] The present application adopts a hydrothermal synthesis method to synthesize zeolite materials. First, a directing agent solution is prepared, then a certain amount of a silicon source is added in a beaker, the directing agent solution is slowly added into the silicon source, the rotation speed is adjusted to make the mixture uniform, then a certain amount of an aluminum source is added, and the stirring is maintained for a certain time to prepare an intermediate gel, a heteroatom source is added into the aluminum source solution prepared in advance to prepare a mixed solution, then the mixed solution is added into the above intermediate gel, the stirring state is maintained to dynamically age for a period of time to make the components of the gel fully mixed and uniform, the gel mixture is added into a crystallization kettle with polytetrafluoroethylene as the inner liner, crystallization is performed for a period of time to make the crystallization complete, the product after crystallization is fully filtered with deionized water, washed, and fully dried in an oven at 120℃ for 18 hours to obtain the prepared heteroatom Y zeolite sample.

[0012] In a specific embodiment of the present application, the aluminum source for synthesizing the heteroatom Y zeolite is at least one of sodium aluminate, aluminum sulfate, aluminum isopropoxide, aluminum hydroxide, pseudo-boehmite, aluminum oxide, and aluminum nitrate, and preferably the aluminum source is aluminum nitrate or aluminum sulfate.

[0013] In a specific embodiment of the present application, the silicon source for synthesizing the heteroatom Y zeolite is at least one of white carbon black, silica sol, solid silica gel, tetraethyl orthosilicate, and water glass, and preferably the silicon source is water glass or silica sol.

[0014] In a specific embodiment of the present application, the heteroatom source for synthesizing the heteroatom Y zeolite is at least one of magnesium sulfate, magnesium nitrate, zirconium sulfate, cobalt nitrate, cobalt sulfate, tin nitrate, ferrous sulfate, and nickel nitrate, and preferably the heteroatom source is cobalt nitrate or magnesium sulfate.

[0015] In a specific embodiment of the present application, the directing agent solution is fully mixed from a base source, a silicon source, an aluminum source, and water, and the molar ratio of the components is Na2O:Al2O3:SiO2:H2O=(5-30):1:(10-25):(250-400), and preferably the molar ratio of the components is Na2O:Al2O3:SiO2:H2O=(10-25):1:(10-20):(350-400).

[0016] In a specific embodiment of the present application, the base source is at least one of sodium hydroxide, potassium hydroxide, sodium oxide, and urea, and preferably the base source is sodium hydroxide.

[0017] In a specific embodiment of the present application, the aging temperature of the directing agent is 25-50℃, and preferably the temperature is 30-40℃.

[0018] In a specific embodiment of the present application, the aging time of the directing agent is 7-24 hours, and preferably the aging time is 15-20 hours.

[0019] In one embodiment of the present application, the aging temperature of the gel is 35-90°C, preferably the aging temperature is 45-55°C.

[0020] In one embodiment of the present application, the dynamic aging time of the gel is 2-8 hours, preferably the dynamic aging time is 3-5 hours.

[0021] In one embodiment of the present application, the crystallization temperature of the gel is 80-180°C, preferably the crystallization temperature is 90-120°C.

[0022] In one embodiment of the present application, the molar ratio of the alkali source, the aluminum source, the heteroatom source, the silicon source and the water source in the gel mixture is Na2O: (Al2O3+M2O x ):SiO2:H2O = (2-8):1:(6-12):(150-250), preferably the molar ratio of the alkali source, the aluminum source, the silicon source and the water source in the gel is Na2O: (Al2O3+M2O x ):SiO2:H2O = (4-6):1:(8-10):(150-200). Wherein M is the heteroatom source, the molar ratio of the heteroatom in the heteroatom source to the aluminum in the aluminum source (M:Al) is (0.25-0.5).

[0023] In one embodiment of the present application, the mass of the directing agent solution accounts for 20%-30% of the total mass of the gel, preferably the mass of the directing agent accounts for 20%-25% of the total mass of the gel.

[0024] The synthesized heteroatom Y zeolite has a framework silicon-aluminum ratio of 6.1-6.5, a crystal particle size of 200-600 nm, a BET specific surface area of 700-850 m 2 / g, an external specific surface area of 57-77 m 2 / g, a total pore volume of 0.38-0.58 cm 3 / g, a mesopore volume of 0.04-0.10 cm 3 / g, and a relative crystallinity of 90%-100%, and has the characteristics of high silicon-aluminum ratio, small crystal particle size, and high relative crystallinity.

[0025] In order to achieve the technical purpose, the heteroatom Y zeolite also needs post-treatment modification, and needs to be doped with rare earth metals and loaded with phosphorus to regulate its acid distribution, acid density and texture properties. The post-modification steps are as follows:

[0026] (a) Dissolve the rare earth metal source in water at 60-95°C to obtain a first component, uniformly mix the heteroatom Y zeolite with water to obtain a second component, slowly drop the first component into the second component, and mix uniformly under vigorous stirring, that is, the heteroatom Y zeolite is subjected to rare earth metal ion exchange treatment, then washed with deionized water, filtered to neutral, and dried at 90-180°C (preferably dried at 120°C).

[0027] In one embodiment of the present application, the rare earth metal source is at least one of lanthanide metals, preferably lanthanum chloride, lanthanum nitrate, cerium chloride, and cerium nitrate.

[0028] In one embodiment of the present application, the loading of the rare earth metal (calculated as rare earth metal oxide) is 1-16 wt%, preferably 1-8 wt%.

[0029] In one embodiment of the present application, the ion exchange temperature of the rare earth metal is 60-95℃, preferably 80-90℃.

[0030] In one embodiment of the present application, the ion exchange time of the rare earth metal is 0.5-4 hours, preferably 1-2 hours.

[0031] (b) The heteroatom Y zeolite after rare earth ion exchange needs to be treated by ammonium ion exchange and hydrothermal calcination, and the ammonium exchange and hydrothermal treatment are generally performed for multiple times, preferably twice.

[0032] In one embodiment of the present application, the ammonium ion exchange is performed as follows:

[0033] The heteroatom Y zeolite after rare earth ion exchange is added to a 0.5-2.0 mol / L ammonium chloride aqueous solution, and the temperature is generally 60-120℃ (preferably 80-95℃), and the exchange is performed at the temperature for 1-3 hours, wherein the mass ratio of the heteroatom Y zeolite to the ammonium chloride aqueous solution is 1:5-20 (preferably 1:10-15).

[0034] In one embodiment of the present application, the hydrothermal calcination is performed as follows:

[0035] The dried heteroatom Y zeolite powder after rare earth ion exchange and ammonium ion exchange is ground and laid flat in a crucible, and then placed in a muffle furnace, the temperature of the muffle furnace is generally 400-800℃ (preferably 650℃), 60-100% water vapor (preferably 100% water vapor) is introduced, and the hydrothermal calcination time is generally 1-6 hours (preferably 2 hours).

[0036] (c) The modified heteroatom Y zeolite obtained in step (b) needs to be further modified by phosphorus

[0037] In one embodiment of the present application, the phosphorus modification is performed as follows:

[0038] The Y zeolite obtained in step (b) is oven-dried at 90-180°C (preferably 120°C) for 12-18 hours (preferably 12 hours), the dried zeolite is ground and laid flat in a large crucible, the crucible is placed in a muffle furnace, the temperature is generally 450-800°C (preferably 550°C), and the zeolite is calcined for 2-6 hours (preferably 4 hours) to obtain a zeolite dry base. The zeolite is impregnated with an equal volume of aqueous diammonium hydrogen phosphate solution or excess impregnation (preferably equal volume impregnation), and the impregnated zeolite is activated at 25-90°C (preferably 25°C) for one day and night, and then calcined in a muffle furnace at a temperature of 400-800°C (preferably 550°C) for 2-6 hours (preferably 4 hours) to obtain a modified Y molecular sieve alkylation catalyst.

[0039] In a specific embodiment of the present application, the loading of diammonium hydrogen phosphate (calculated as phosphorus pentoxide) is 1-20 wt%, preferably the loading is 1-12 wt%.

[0040] The rare earth ion-exchanged and equal volume impregnated diammonium hydrogen phosphate modified heteroatomic Y zeolite of the present application has excellent performance, a framework silica-alumina ratio of 18-50, a crystal particle size of 200-600 nm, a BET specific surface area of 620-750 m 2 / g, an external specific surface area of 100-150 m 2 / g, a total pore volume of 0.430-0.580 cm 3 / g, a mesopore volume of 0.180-0.300 cm 3 / g, a relative crystallinity of 75%-90%, a total acid amount of 0.200-0.300 mmol / g, a strong acid amount of 0.080-0.140 mmol / g, an acid center strength of 0.40-0.52, and has the characteristics of high silica-alumina ratio, small crystal size, high relative crystallinity, large specific surface area, high mesopore, low total acid density but high acid center strength.

[0041] The present application also provides a process for synthesizing long-chain alkyl naphthalene base oil, wherein the alkyl naphthalene has only one identical C4-C 22 alkyl substituent, and the method comprises the following steps: using the above-mentioned heteroatomic Y zeolite modified by rare earth and doped with phosphorus as a catalyst, and allowing naphthalene to undergo alkylation with single or mixed C4-C 22 α-olefins to generate the above-mentioned long-chain alkyl naphthalene.

[0042] In an embodiment of the present application, the temperature of the alkylation reaction is 100-250°C, preferably 120-205°C, and more preferably 120-180°C; the pressure of the alkylation reaction is 0.1-2.0 atm, preferably 0.8-1.0 atm, and more preferably normal pressure; the alkylation reaction is performed for 1-12 hours, preferably 2-6 hours, and more preferably 2-4 hours; and the alkylation reaction is performed in an inert atmosphere, preferably nitrogen.

[0043] In an embodiment of the present application, the alkylation reaction is performed as follows: the reaction system is maintained in a nitrogen atmosphere, the solvent is first added, then the naphthalene is added, the naphthalene is heated to 90°C to completely melt the naphthalene, the naphthalene is mixed with the solvent to form a uniform mixture, the catalyst is then added to the reaction system, the target reaction temperature is reached, the alpha-olefin is slowly added dropwise to the reaction system, and the alkylation reaction is completed after 2-4 hours of reaction.

[0044] In an embodiment of the present application, the alpha-olefin used is a single olefin or a mixture of several olefins, and is preferably a C6-C 20 The alpha-olefin is more preferably a C 10 ~C 16 The alpha-olefin is more preferably a C

[0045] In an embodiment of the present application, the solvent used is a C8-C 16 The normal alkane is preferably a C 12 ~C 16 The normal alkane is preferably a C

[0046] In an embodiment of the present application, the molar ratio of naphthalene to olefin is 1:(0.5-2.5), and is preferably 1:(0.8-1.2).

[0047] In an embodiment of the present application, the mass ratio of the solvent to (olefin+naphthalene) is preferably 1:(1-2).

[0048] In an embodiment of the present application, the mass ratio of naphthalene to Y zeolite is preferably 1:(0.05-0.15).

[0049] In an embodiment of the present application, after the alkylation reaction is completed, the unreacted raw materials and the solvent are removed from the crude product by vacuum distillation, the Y zeolite is then collected by centrifugation, and the reaction product is obtained.

[0050] In an embodiment of the present application, the collected Y zeolite catalyst is hydrothermally calcined and regenerated, and the regenerated catalyst is used to synthesize alkylnaphthalene.

[0051] The present application also provides the use of the alkylnaphthalene prepared by the above method as a Group V alkylnaphthalene lubricating oil base oil.

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

[0053] The heteroatom Y zeolite modified by rare earth and doped by phosphorus in the present application has excellent properties, does not cause equipment corrosion and does not pollute the environment, and is a green alkylation catalyst. The modified Y zeolite has the characteristics of high relative crystallinity, high framework silica-alumina ratio, large specific surface area, large mesopore volume, strong acid strength and extremely low total acid density. Therefore, the catalyst of the present application is not prone to carbon deposition, has a long service life, and has very good product selectivity. The alkyl naphthalene synthesized in the present application is all mono-substituted alkyl naphthalene, and the ratio of α-alkyl naphthalene to β-alkyl naphthalene is at least 1.5. Therefore, the alkyl naphthalene has excellent thermal oxygen stability and suitable viscosity. Moreover, the catalyst of the present application can be regenerated by simple hydrothermal calcination. After regeneration for 5 times, the properties of the base oil catalyzed and synthesized by the catalyst are still excellent. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 XRD pattern of the alkylation catalyst;

[0055] Figure 2 SEM pattern of the alkylation catalyst (a~e: catalysts 1~5). DETAILED DESCRIPTION

[0056] The preparation and modification method of the catalyst of the present application and the synthesis process of alkyl naphthalene are further described below in combination with specific examples. However, the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0057] Example 1

[0058] At a water bath temperature of 40℃, 60.5g of water glass solution (Na2O: 9.96wt%, SiO2: 31.5wt%) was added into a beaker, dynamic stirring was maintained, then 35.6g of sodium metaaluminate solution (Na2O: 27wt%, Al2O3: 4.5wt%) was added into the beaker, and finally 25g of deionized water was added into the beaker, dynamic stirring was maintained for 90 minutes, and then the beaker was left to stand and age for 20 hours, thereby obtaining a directing agent solution.

[0059] At a water bath temperature of 60℃, 170g of water glass solution (Na2O: 9.96wt%, SiO2: 31.5wt%) was added into another beaker, dynamic stirring was maintained, 100g of the directing agent solution and 19.78g of sodium metaaluminate solution (Na2O: 27wt%, Al2O3: 4.5wt%) were slowly poured into the beaker in sequence, dynamic stirring was maintained for 30 minutes to make the components fully mixed and uniform, 79.01g of aluminum sulfate solution (Al2O3: 24wt%, H2SO4: 18wt%) was slowly poured into the beaker, dynamic stirring was maintained for 30 minutes to make the components fully mixed and uniform, and then the beaker was left to stand and age for 20 hours, thereby obtaining a catalyst precursor solution. 3:A mixed solution was prepared by mixing 9 wt%) and 2.62 g CoSO4. The mixed solution was slowly added to the above beaker and dynamically aged for 2 hours to obtain a gel mixture. The gel mixture was added to a polytetrafluoroethylene-lined crystallization vessel and crystallized at 120°C for 14 hours. The crystallized product was thoroughly filtered with deionized water, washed, and thoroughly dried in an oven at 120°C for 18 hours to obtain a heteroatom Y zeolite sample.

[0060] The heteroatom Y zeolite synthesized in Example 1 has a crystallinity of 88% and a BET specific surface area of ​​750 m². 2 / g, with an external specific surface area of ​​47m² 2 / g, total pore volume is 0.35cm³ 3 / g, mesopore volume is 0.03cm³ 3 / g, with a framework silicon-to-aluminum ratio of 5.9 and a grain size of approximately 350nm.

[0061] Example 2

[0062] At a water bath temperature of 34℃, 50g of water glass solution (Na2O: 9.96wt%, SiO2: 31.5wt%) was added to a beaker and stirred dynamically. Then, 35g of sodium aluminate solution (Na2O: 27wt%, Al2O3: 4.5wt%) was added to the beaker, followed by 35g of deionized water. The mixture was stirred dynamically for 90 minutes and then allowed to stand for 20 hours to age, thus obtaining the directing agent solution.

[0063] At a water bath temperature of 55℃, 150g of water glass solution (Na2O: 9.96wt%, SiO2: 31.5wt%) was added to another beaker, and the mixture was stirred dynamically. Then, 100g of the directing agent solution and 13.69g of sodium aluminate solution (Na2O: 27wt%, Al2O3: 4.5wt%) were slowly poured into the beaker sequentially, and the mixture was stirred dynamically for 30 minutes to ensure thorough mixing. Finally, 68.85g of aluminum sulfate solution (Al2O3) was added. 3: A mixed solution was prepared by mixing 9 wt%) and 2.78 g MgSO4. The mixed solution was slowly added to the above beaker and dynamically aged for 2 hours to obtain a gel mixture. The gel mixture was added to a polytetrafluoroethylene-lined crystallization vessel and crystallized at 120°C for 16 hours. The crystallized product was thoroughly filtered with deionized water, washed, and thoroughly dried in an oven at 120°C for 18 hours to obtain a heteroatom Y zeolite sample.

[0064] The heteroatom Y zeolite synthesized in Example 2 has a crystallinity of 91% and a BET specific surface area of ​​850 m². 2 / g, with an external specific surface area of ​​57m² 2 / g, total pore volume is 0.38cm³3 / g, mesopore volume is 0.04 cm 3 / g, the framework silica-alumina ratio is 6.2, and the crystal size is about 200 nm, preferably as a post-modified zeolite precursor.

[0065] Example 3

[0066] The synthesized heteroatom Y zeolite is used as a post-modified zeolite precursor, wherein the rare earth Ce source is selected as CeCl3·7H2O, and the input amount of the rare earth Ce relative to the heteroatom Y zeolite is 4wt% (calculated as Ce2O3). The CeCl3·7H2O is weighed and added to a beaker containing water and stirred to dissolve, and then the heteroatom Y zeolite is added to the beaker, heated in a water bath at 90°C for 1 hour, washed, filtered and dried. Then two ammonium exchanges and two hydrothermal treatments are performed, and the raw material ratio in the molecular sieve ammonium exchange is 1:1:10 (mass ratio) of molecular sieve:ammonium chloride:deionized water, heated and stirred in a water bath at 90°C for 1 hour, and the pH value is adjusted to 3.0-3.3 with 0.2 mol / L hydrochloric acid during the water bath process. Then the sample is washed with deionized water, filtered and dried in an oven at 120°C, the dried molecular sieve sample is ground and uniformly spread on the wall of the crucible, and then placed in a muffle furnace at 650°C and 100% water vapor for 2 hours. The same ammonium exchange and hydrothermal calcination process is performed once again to obtain the rare earth metal ion-exchanged heteroatom Y zeolite.

[0067] The rare earth metal ion-exchanged heteroatom Y zeolite is used as a phosphorus-modified zeolite precursor, and the phosphorus source is selected as diammonium hydrogen phosphate, and the input amount of the diammonium hydrogen phosphate relative to the zeolite is 1wt% (calculated as P2O5). The rare earth-modified Y zeolite is placed in a 120°C oven for sufficient drying, and then the zeolite sample is placed in a 550°C muffle furnace for calcination for 4 hours to obtain a zeolite dry base. The zeolite dry base is impregnated with an equal volume of an aqueous solution of diammonium hydrogen phosphate, and then the impregnated sample is activated at room temperature for 24 hours, and then the sample is placed in a 550°C muffle furnace for calcination for 4 hours to complete the phosphorus modification of the zeolite.

[0068] The rare earth-modified and phosphorus-modified heteroatom Y zeolite can be used as the alkylation catalyst 1 of the present application.

[0069] Example 4

[0070] The input amount of the rare earth Ce relative to the heteroatom Y zeolite is 4wt% (calculated as Ce2O3), and the input amount of the diammonium hydrogen phosphate relative to the zeolite is 4wt% (calculated as P2O5). The other conditions are the same as in Example 1, and the product is an alkylation catalyst 2.

[0071] Example 5

[0072] The amount of rare earth Ce added to the heteroatom Y zeolite is 8wt% (calculated as Ce2O3). The amount of diammonium hydrogen phosphate added to the zeolite is 8wt% (calculated as P2O5). Other conditions are the same as in Example 1, which is alkylation catalyst 3.

[0073] Example 6

[0074] The amount of rare earth Ce added to the heteroatom Y zeolite is 4wt% (calculated as Ce2O3). The amount of diammonium hydrogen phosphate added to the zeolite is 12wt% (calculated as P2O5). Other conditions are the same as in Example 1, which is alkylation catalyst 4.

[0075] Example 7

[0076] The amount of rare earth Ce added to the heteroatom Y zeolite is 1wt% (calculated as Ce2O3). The amount of diammonium hydrogen phosphate added to the zeolite is 16wt% (calculated as P2O5). Other conditions are the same as in Example 1, which is alkylation catalyst 5.

[0077] Examples 3-7 are the preparation methods of the alkylation catalysts of the present application, and the properties of the synthesized alkylation catalysts are as follows:

[0078] Table 1. Framework properties of the alkylation catalysts

[0079]

[0080] Table 2. Texture properties of the alkylation catalysts

[0081]

[0082] Table 3. Acid property characterization of the alkylation catalysts

[0083]

[0084] The alkylation catalysts prepared in the present application have more excellent acid properties and texture properties compared to conventional USY zeolites, such as a larger external specific surface area, a larger mesopore volume, a reduced total acid density but a greatly increased B / L and enhanced acid center strength, so that the prepared alkylation catalysts are less likely to be deactivated by carbon deposition, have enhanced hydrothermal stability and are easy to regenerate, and have higher alkylation selectivity and catalytic activity.

[0085] The olefins used in the following examples are all straight-chain a-olefins without any branched chains, the kinematic viscosity of the products at 40°C and 100°C is determined according to ASTM D445, the viscosity index is determined according to ASTM D2270, the flash point is determined according to ASTM D92, the pour point is determined according to GB / T 3535, the acid value is determined according to GB / T 7304-2014 method, the water content is determined according to GB / T 11146-2009, and the products are qualitatively characterized by nuclear magnetic resonance hydrogen spectrum and GC-MS. The thermal oxygen stability of the product is characterized by the initial oxidation temperature of DSC, and the initial oxidation temperature of DSC is tested according to SN / T3950-2014.

[0086] Example 8

[0087] In a nitrogen inert environment, 34.84 g of n-dodecane solvent and 25 g of naphthalene were first added to a flask, then 3.75 g of catalyst 5 was added, heated to 160°C, and the naphthalene and n-dodecane solvent were fully mixed and uniform, 32.83 g of 1-decene was added to the flask at a rate of 1 drop per second with a constant pressure dropping funnel, and the alkylation reaction was completed after 4 hours of reaction. The material in the flask was distilled under reduced pressure at a temperature of 220°C and a gauge pressure of -0.1 Mpa to remove unreacted olefins, naphthalene and n-dodecane solvent to obtain a crude product. After the solid acid catalyst in the crude product was fully centrifuged and collected, the final product was obtained. The product obtained was transparent golden yellow, the conversion rate of naphthalene was 95.5%, the selectivity was 99.9%, and the product yield was 95.4%. The product was characterized by GC-MS and nuclear magnetic resonance hydrogen spectrum, and it was found that the product was naphthalene with only one decane substituent.

[0088] Example 9

[0089] In a nitrogen inert environment, 43.45 g of n-dodecane solvent and 28 g of naphthalene were first added to a flask, then 4.20 g of catalyst 4 was added, heated to 160°C, and the naphthalene and n-dodecane solvent were fully mixed and uniform, 44.12 g of 1-dodecene was added to the flask at a rate of 1 drop per second with a constant pressure dropping funnel, and the alkylation reaction was completed after 4 hours of reaction. The material in the flask was distilled under reduced pressure at a temperature of 220°C and a gauge pressure of -0.1 Mpa to remove unreacted olefins, naphthalene and n-dodecane solvent to obtain a crude product. After the solid acid catalyst in the crude product was fully centrifuged and collected, the final product was obtained. The product obtained was transparent golden yellow, the conversion rate of naphthalene was 97.5%, the selectivity was 99.9%, and the product yield was 97.3%. The product was characterized by GC-MS and nuclear magnetic resonance hydrogen spectrum, and it was found that the product was naphthalene with only one dodecane substituent.

[0090] Example 10

[0091] In a flask, 51.30 g of n-dodecane solvent and 30 g of naphthalene were first added under nitrogen inert environment, then 4.50 g of catalyst 4 was added, heated to 160°C, naphthalene and n-dodecane solvent were mixed uniformly, 55.15 g of 1-tetradecene was added into the flask at a rate of 1 drop per second by using a constant pressure dropping funnel, the alkylation reaction was completed after 4 hours, the unreacted olefins, naphthalene and n-dodecane solvent were removed by distillation under reduced pressure at a temperature of 220°C and a gauge pressure of -0.1 Mpa to obtain a crude product, the solid acid catalyst was collected by centrifugation, and the final product was obtained, the obtained product was transparent golden yellow, the conversion rate of naphthalene was 96.5%, the selectivity was 99.9%, and the product yield was 96.4%. The product was characterized by GC-MS and nuclear magnetic resonance hydrogen spectrum, and it was found that the product was naphthalene with only one tetradecane substituent.

[0092] Example 11

[0093] In a flask, 51.30 g of n-dodecane solvent and 30 g of naphthalene were first added under nitrogen inert environment, then 4.50 g of catalyst 4 was added, heated to 160°C, naphthalene and n-dodecane solvent were mixed uniformly, 55.15 g of 1-tetradecene was added into the flask at a rate of 1 drop per second by using a constant pressure dropping funnel, the alkylation reaction was completed after 4 hours, the unreacted olefins, naphthalene and n-dodecane solvent were removed by distillation under reduced pressure at a temperature of 220°C and a gauge pressure of -0.1 Mpa to obtain a crude product, the solid acid catalyst was collected by centrifugation, and the final product was obtained, the obtained product was transparent golden yellow, the conversion rate of naphthalene was 96.5%, the selectivity was 99.9%, and the product yield was 96.4%. The product was characterized by GC-MS and nuclear magnetic resonance hydrogen spectrum, and it was found that the product was naphthalene with only one tetradecane substituent.

[0094] Example 12

[0095] In a flask, 57.08 g of n-dodecane solvent and 35 g of naphthalene were first added under nitrogen inert environment, and then 5.25 g of catalyst 5 was added, heated to 160°C, and the naphthalene and n-dodecane solvent were mixed uniformly. An olefin mixture composed of 11.49 g of 1-decene, 13.79 g of 1-dodecene, 16.09 g of 1-tetradecene, and 18.39 g of 1-hexadecene was added to the flask at a rate of 1 drop per second using a constant-pressure dropping funnel, and the alkylation reaction was completed after 4 hours. The materials in the flask were distilled under reduced pressure at a temperature of 220°C and a gauge pressure of -0.1 Mpa to remove unreacted olefins, naphthalene, and n-dodecane solvent to obtain a crude product. After the solid acid catalyst was collected by centrifugation, the final product was obtained. The product was transparent golden yellow, the conversion rate of naphthalene was 96.7%, the selectivity was 99.9%, and the product yield was 96.4%. GC-MS and nuclear magnetic resonance hydrogen spectrum characterization of the product showed that the product was monosubstituted naphthalene with only one alkyl substituent, and the product was a mixture of naphthalene with a decane substituent, naphthalene with a dodecane substituent, naphthalene with a tetradecane substituent, and naphthalene with a hexadecane substituent.

[0096] Example 13

[0097] In a flask, 51.30 g of n-dodecane solvent and 30 g of naphthalene were first added under nitrogen inert environment, and then 4.5 g of catalyst 5 was added, heated to 130°C, and the naphthalene and n-dodecane solvent were mixed uniformly. 55.15 g of 1-tetradecene was added to the flask at a rate of 1 drop per second using a constant-pressure dropping funnel, and the alkylation reaction was completed after 4 hours. The materials in the flask were distilled under reduced pressure at a temperature of 220°C and a gauge pressure of -0.1 Mpa to remove unreacted olefins, naphthalene, and n-dodecane solvent to obtain a crude product. After the solid acid catalyst was collected by centrifugation, the final product was obtained. The product was transparent golden yellow, the conversion rate of naphthalene was 97.5%, the selectivity was 99.9%, and the product yield was 97.4%. GC-MS and nuclear magnetic resonance hydrogen spectrum characterization of the product showed that the product was naphthalene with only one tetradecane substituent.

[0098] Example 14

[0099] In a flask, 40.22 g of n-dodecane solvent and 30 g of naphthalene were first added under nitrogen inert environment, then 4.5 g of catalyst 5 was added, heated to 130°C, and the naphthalene and n-dodecane solvent were mixed uniformly, 36.77 g of 1-tetradecene was added into the flask at a rate of 1 drop per second by using a constant pressure dropping funnel, the alkylation reaction was completed after 4 hours, the unreacted olefins, naphthalene and n-dodecane solvent were removed by distillation at a temperature of 220°C and a pressure of -0.1 MPa to obtain a crude product, the solid acid catalyst was collected by centrifugation, and the final product was obtained, the product was transparent golden yellow, the conversion rate of naphthalene was 96.7%, the selectivity was 99.9%, and the product yield was 96.4%. The product was characterized by GC-MS and nuclear magnetic resonance hydrogen spectrum, and it was found that the product was naphthalene with only one tetradecane substituent.

[0100] Comparative Example 1

[0101] Comparative Example 1 is a commercially available alkyl naphthalene base oil, which has a kinematic viscosity of 29.0 cst at 40°C, a kinematic viscosity of 4.7 cst at 100°C, a viscosity index of 74, a pour point of -39°C, a flash point of 222°C, a water content of <50 ppm, and a total acid value of <50 ppm.

[0102] The properties of the lubricating oil base oils prepared in Examples 8-14 and Comparative Example 1 are shown in Table 4:

[0103] Table 4. Properties of the lubricating oil base oils prepared in the examples and comparative example

[0104]

[0105] As can be seen from Table 4, the lubricating oil base oils prepared in the examples of the present application have comparable performance to the commercially available alkyl naphthalene base oil of Comparative Example 1, but have a higher DSC initial oxidation temperature, and therefore have more excellent thermal oxygen stability.

[0106] The above examples are part of the preferred embodiments of the present application and cannot be regarded as limitations of the present application. Any changes and modifications made by those skilled in the art to the technical solutions of the present application are within the scope of protection of the present application.

Claims

1. A process for the preparation of a modified Y molecular sieve alkylation catalyst heteroatom doped rare earth metal and phosphorus supported, characterized in that, The method comprises the following steps: (1) Synthesizing zeolite material by hydrothermal synthesis method: first, preparing a directing agent solution, then adding a certain amount of silicon source into a beaker, slowly adding the directing agent solution into the silicon source, adjusting the rotation speed to make them mix uniformly, then adding a certain amount of aluminum source and keeping stirring for a certain time to prepare an intermediate gel, adding a heteroatom source into the aluminum source solution prepared in advance to prepare a mixed solution, then adding the mixed solution into the intermediate gel, keeping stirring to dynamically age for a certain time to make the components mix uniformly, adding the gel mixture into a crystallization kettle with polytetrafluoroethylene as the inner liner, crystallizing for a certain time to make it completely crystallize, and then filtering, washing and drying the product crystallized at 120℃ for 18 hours to obtain a heteroatom Y zeolite sample; (2) Rare earth metal doping modification: dissolving a rare earth metal source in water to obtain a first component, mixing the heteroatom Y zeolite with water to obtain a second component, slowly adding the first component into the second component and mixing uniformly under intense stirring, namely, performing rare earth metal ion exchange treatment on the heteroatom Y zeolite, then washing and filtering the product to neutral, and drying at 90-180℃; (3) Ammonium ion exchange treatment: adding the heteroatom Y zeolite after rare earth ion exchange into an aqueous ammonium chloride solution, and standing for 1-3 hours at a temperature of 60-120℃; (4) Hydrothermal calcination treatment: grinding the dried heteroatom Y zeolite powder after rare earth ion exchange and ammonium ion exchange, laying it flat in a crucible, then putting it into a muffle furnace, setting the temperature of the muffle furnace to 400-800℃, introducing 60-100% water vapor, and hydrothermal calcining for 1-6 hours; (5) Phosphorus modification treatment: drying the Y zeolite after hydrothermal calcination at 90-180℃ for 12-18 hours, grinding the dried zeolite, laying it flat in a large crucible, putting the crucible into a muffle furnace, setting the temperature to 450-800℃, and calcining for 2-6 hours to obtain a zeolite dry base; immersing the zeolite in an equal volume of a diammonium hydrogen phosphate aqueous solution, activating the immersed zeolite at 25-90℃ for one day, and then calcining in a muffle furnace, wherein the temperature of the muffle furnace is 400-800℃ and the high-temperature calcination time is 2-6 hours, to obtain a modified Y molecular sieve alkylation catalyst; The heteroatom source is at least one of magnesium sulfate, magnesium nitrate, zirconium sulfate, cobalt nitrate, cobalt sulfate, tin nitrate, ferrous sulfate and nickel nitrate; The directing agent solution is prepared by fully mixing an alkali source, a silicon source, an aluminum source and water, and the molar ratio of the components is Na2O:Al2O3:SiO2:H2O=(5-30):1:(10-25):(250-400).

2. The production method according to claim 1, characterized by, In step (1), the aluminum source is at least one of sodium metaaluminate, aluminum sulfate, aluminum isopropoxide, aluminum hydroxide, pseudo-boehmite, aluminum oxide and aluminum nitrate; and the silicon source is at least one of white carbon black, silica sol, solid silica gel, tetraethyl orthosilicate and water glass.

3. The preparation method according to claim 2, characterized in that, The alkali source is at least one of sodium hydroxide, potassium hydroxide, sodium oxide and urea; the aging temperature of the directing agent is 25-50℃, and the aging time is 7-24 hours.

4. The method of claim 1, wherein, The aging temperature of the gel in step (1) is 35-90℃, and the dynamic aging time is 2-8 hours; the crystallization temperature of the gel is 80-180℃.

5. The preparation method according to claim 1, characterized in that, The molar ratio of the alkali source, the aluminum source, the heteroatom source, the silicon source, and the water source in the gel mixture in step (1) is Na2O:(Al2O3+M2O x ):SiO2:H2O=(2-8):1:(6-12):(150-250), wherein M is the heteroatom source, and the molar ratio of the heteroatom in the heteroatom source to the aluminum in the aluminum source is M:Al=0.25-0.

5.

6. The method of claim 1, wherein, The mass of the directing agent solution in step (1) accounts for 20%-30% of the total mass of the gel mixture.

7. The preparation method according to claim 1, characterized in that, The rare earth metal source in step (2) is one of lanthanum chloride, lanthanum nitrate, cerium chloride and cerium nitrate; the loading of the rare earth metal is 1-16wt% in terms of rare earth metal oxide.

8. The preparation method according to claim 1, characterized in that, The loading of diammonium hydrogen phosphate in step (5) is 1-20wt% in terms of phosphorus pentoxide.

9. A modified Y molecular sieve alkylation catalyst doped with heteroatoms, rare earth metals and loaded with phosphorus, prepared by the preparation method in any one of claims 1-8.

10. The use of the modified Y molecular sieve alkylation catalyst according to claim 9 in the synthesis of long chain alkyl naphthalene base oil, characterized in that, The synthesized alkyl naphthalenes are all mono-substituted alkyl naphthalenes, and the ratio of α-alkyl naphthalene / β-alkyl naphthalene is at least 1.5.

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