Sulfonated USY molecular sieve and application thereof in catalytic preparation of long-chain alkyl naphthalene

Abstract

The invention discloses a sulfonated USY molecular sieve and application thereof in catalytic preparation of long-chain alkyl naphthalene, and relates to the technical field of lubricating oil. A preparation method of a sulfonated USY molecular sieve comprises the following steps: adding a USY molecular sieve into an acid solution, reacting to obtain a solid product, washing the solid product to be neutral, drying, and roasting to obtain an acid modified USY molecular sieve; adding the acid-modified USY molecular sieve into an organic solvent for reaction, then adding sulfydryl-containing siloxane, refluxing under the protection of nitrogen, carrying out suction filtration to obtain a mixture of the sulfydryl-containing siloxane and the USY molecular sieve, and washing and drying the mixture to obtain a filter cake; and adding hydrogen peroxide into the dried filter cake, uniformly mixing, carrying out suction filtration, washing, and drying to obtain the sulfonated USY molecular sieve. The sulfonated USY molecular sieve has good stability and catalytic performance, is high in alkylation reaction conversion rate and selectivity, and can be repeatedly used.

Description

Technical Field

[0001] The invention relates to the technical field of lubricating oil, in particular to a sulfonated USY molecular sieve and its application in catalytic preparation of long-chain alkyl naphthalene. Background Art

[0002] Alkyl naphthalene has the advantages of high oxidation stability, high flash point, good thermal stability and high safety. Among them, long-chain alkyl naphthalene has excellent additive solubility, good anti-emulsification performance and good compatibility. It occupies an important position in synthetic lubricants and is widely used in hydraulic oil, gear oil, heat transfer oil, transformer oil, refrigeration oil, compressor oil, liquid crystal and other fields. The production method of alkyl naphthalene is to prepare it by alkylation reaction of long-chain α-olefin single component or multi-component mixture with naphthalene under acid catalyst conditions. It belongs to the positive carbon ion mechanism. Under the action of acid catalyst, olefin forms positive carbon ion, which is rearranged to obtain positive carbon ion at α-n position, and then interacts with naphthalene to form alkyl naphthalene.

[0003] The traditional preparation of long-chain alkylnaphthalene uses traditional liquid inorganic acids such as trifluoromethanesulfonic acid, concentrated sulfuric acid and hydrofluoric acid or Lewis acids such as aluminum chloride and ferric chloride as catalysts, which have serious corrosion problems on equipment, making it difficult to separate the product and the catalyst or the separation cost is high, and the environmental pressure is high, which does not meet the requirements of green chemistry. At present, the use of solid acid catalysts has defects such as complex catalyst preparation process, high price, low processing capacity, poor activity and stability, and harsh reaction conditions, resulting in complex processes and high production costs, which limits the application and promotion of this technology.

[0004] Patent CN101205161A provides a method for preparing alkylnaphthalene by reacting long-chain olefins with naphthalene using an ultrafine silica-supported heteropolyacid catalyst at normal pressure. The product obtained by this method has low chroma and the catalyst is easy to separate. However, due to the excess of olefins, coking is very likely to occur when the catalyst is used multiple times, and multiple distillations are required to obtain high-viscosity components, which is cumbersome to operate.

[0005] Patent CN1029611C uses phosphotungstic acid or silicotungstic acid and their salts as catalysts to catalyze the alkylation reaction of C2-C20 olefins and aromatics with high yields. However, the reaction requires pretreatment with cyclohexane solvent and is carried out under pressure in a closed container. Large-scale industrialization has high costs and safety risks.

[0006] Patent CN114507110A provides a method using trifluoromethanesulfonic acid and / or methanesulfonic acid as catalysts, which can continuously produce alkylnaphthalene by adding an extractant to separate the incompletely reacted raw materials and controlling a reasonable space velocity. However, since this method uses a liquid acid catalyst, alkali washing, water washing and other steps are required after the reaction, and the liquid acid is highly corrosive to the equipment, which is not conducive to long-term continuous and stable production of industrial equipment.

[0007] Wang Guiru et al. reported the synthesis of long-chain alkylnaphthalene by HY molecular sieve, and compared the catalytic effect of β molecular sieve, screened out the appropriate reaction temperature, catalyst particle size and feed space velocity, and obtained a high olefin conversion rate and selectivity. The catalyst can be reused by regeneration. However, this method requires the addition of a large amount of cyclohexane as a solvent, which is not conducive to post-processing and has high cost for industrial application.

[0008] Patent CN105289747A provides a supported ultra-stable Y molecular sieve catalyst and its preparation method and a method for catalyzing the synthesis of long-chain alkylnaphthalene. The loaded Y molecular sieve can continuously and stably catalyze the alkylation reaction of long-chain olefins and naphthalene in a fixed bed for a long time. The prepared long-chain alkylnaphthalene has low chroma and low acid value, and has certain application prospects. However, this method requires the addition of n-heptane as a solvent, and the addition ratio of n-heptane is as high as 17mL n-heptane / 1g naphthalene, and the reaction is under pressure. A large amount of energy consumption is required to distill n-heptane after the reaction, and the industrialization cost is high.

[0009] Therefore, the research and development of high-activity solid acid catalysts for the alkylation of long-chain olefins with naphthalene to prepare long-chain alkylnaphthalene is in line with the development concept of green environmental protection, and exploring new catalyst reaction technology is the focus of current research. The development of highly active and stable heterogeneous solid acid catalysts for catalytic alkylation of naphthalene and long-chain olefins has important application value. Summary of the invention

[0010] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a sulfonated USY molecular sieve and its application in the catalytic preparation of long-chain alkylnaphthalene. The present invention overcomes the problems of the prior art that the reaction needs to add a solvent, the product separation operation is cumbersome, the liquid acid catalyst is easy to corrode the equipment, and it does not conform to green chemistry. In addition, the sulfonated USY molecular sieve is used as an alkylation reaction catalyst, which has good stability and catalytic performance, high alkylation reaction conversion rate and selectivity, good reproducibility, and can be reused.

[0011] To achieve the above object, the technical solution adopted by the present invention is:

[0012] In a first aspect, the present invention provides a method for preparing a sulfonated USY molecular sieve, comprising the following steps:

[0013] (1) adding a USY molecular sieve having a silicon-aluminum ratio of 8-35 to an acid solution having a concentration of 0.05-0.5 mol / L, the ratio of the USY molecular sieve to the acid solution being 1 g: (10-50) mL, the reaction temperature being 40-100° C., the reaction time being 2-5 h, and obtaining a solid product after the reaction, washing the solid product until the washing liquid is neutral, drying, and calcining to obtain an acid-modified USY molecular sieve;

[0014] (2) adding the acid-modified USY molecular sieve to an organic solvent, stirring and refluxing at 80-130° C. for 0.5-2 h, then adding siloxane containing a mercapto group, refluxing under nitrogen protection, filtering to obtain a mixture, washing the mixture, and drying to obtain a filter cake;

[0015] (3) adding hydrogen peroxide to the dried filter cake in step (2), mixing evenly, filtering, washing, and drying to obtain the sulfonated USY molecular sieve.

[0016] In the present invention, if the silicon-aluminum ratio is too large or too small, the activity of the sulfonated USY molecular sieve will be affected; the concentration of the acid solution, the reaction temperature of the USY molecular sieve and the acid solution, and the reaction time will affect the activity of the sulfonated USY molecular sieve, thereby affecting the conversion rate of olefins. Therefore, the present invention is conducive to improving the activity of the sulfonated USY molecular sieve by controlling the silicon-aluminum ratio of the USY molecular sieve, the concentration of the acid solution, the reaction temperature, and the reaction time within the above range.

[0017] Preferably, the acid in step (1) is one of oxalic acid, citric acid, hydrochloric acid and sulfuric acid. More preferably, the acid solution is oxalic acid solution.

[0018] Preferably, in step (2), the mass ratio of the acid-modified USY molecular sieve to the mercapto-containing siloxane is (0.2-1.6):1.

[0019] Preferably, the mercapto-containing siloxane in step (2) is at least one of (3-mercaptopropyl)trimethoxysilane, 3-mercaptopropyltrimethylsilane, mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethylsilane.

[0020] More preferably, the mercapto-containing siloxane in step (2) is (3-mercaptopropyl)trimethoxysilane.

[0021] Preferably, the solid product is calcined at a temperature of 400-650° C. and for a time of 2-4 hours in step (1).

[0022] Preferably, in step (3), the ratio of the dried filter cake to hydrogen peroxide is 1 g: (20-100) mL.

[0023] In a second aspect, the present invention also provides a sulfonated USY molecular sieve prepared by the above method.

[0024] In a third aspect, the present invention further provides an application of a sulfonated USY molecular sieve in catalytically preparing long-chain alkyl naphthalene, wherein the preparation method of the long-chain alkyl naphthalene comprises the following steps:

[0025] (1) adding sulfonated USY molecular sieve to naphthalene and long-chain olefins for alkylation reaction at a reaction temperature of 100-170° C. for a reaction time of 0.5-1.5 h to obtain a crude product of alkyl naphthalene; the molar ratio of naphthalene to the long-chain olefin is (1-3):1; the mass of the sulfonated USY molecular sieve is 0.3-6% of the total mass of the naphthalene and the long-chain olefin;

[0026] (2) filtering the obtained alkyl naphthalene crude product, removing the incompletely reacted long-chain olefins and naphthalene by vacuum distillation, and then adding activated clay to decolorize the product at a temperature of 80-140° C. for a heating time of 20-120 min, and obtaining a first alkyl naphthalene lubricating oil base oil after decolorization;

[0027] (3) The first alkylnaphthalene lubricating oil base oil is subjected to vacuum distillation at 180-230° C. to obtain a second alkylnaphthalene lubricating oil base oil.

[0028] The invention uses excess naphthalene to react with sulfonated USY molecular sieve and long-chain olefins, removes unreacted raw materials and performs vacuum distillation to quickly separate and obtain the first alkyl naphthalene lubricating oil base oil, and further distills to obtain the second alkyl naphthalene lubricating oil base oil.

[0029] If the reaction temperature, reaction time, and ratio of the sulfonated USY molecular sieve to naphthalene and long-chain olefins, the sulfonated USY15 molecular sieve to naphthalene and long-chain olefins will affect the conversion rate of the olefins, therefore, the present invention controls the reaction temperature, reaction time, and ratio of the sulfonated USY molecular sieve to naphthalene and long-chain olefins within the above range, which is beneficial to improving the conversion rate of the olefins.

[0030] Preferably, the viscosity of the first alkyl naphthalene lubricant base oil in step (2) is 12-14 mm 2 / s, the viscosity of the second alkyl naphthalene lubricant base oil is 1-3mm 2 / s.

[0031] Preferably, the long-chain olefin in step (1) is C8-C 18 of linear α-olefins.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) The sulfonated USY molecular sieve catalyst used in the present invention has higher catalytic activity than the unmodified USY molecular sieve. Under preferred conditions, the reaction conversion rate is higher than 95%. The catalyst is pollution-free, easy to separate, and can be reused. The reaction is carried out under normal pressure, the reaction conditions are mild, and the catalyst has high safety.

[0034] (2) The present invention does not require the addition of solvents such as cyclohexane and n-heptane. After the reaction, the unreacted raw materials can be removed to directly obtain the high-viscosity alkyl naphthalene lubricant base oil. The separation step is simple and efficient.

[0035] (3) The high-viscosity alkyl naphthalene lubricating oil base oil obtained by the present invention can still obtain a low-viscosity alkyl naphthalene lubricating oil base oil through further distillation. DETAILED DESCRIPTION

[0036] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments, but the protection scope and implementation methods of the present invention are not limited thereto.

[0037] Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0038] In the present invention, USY molecular sieves are commercially available products produced by Zhuoran Environmental Protection Technology (Dalian) Co., Ltd., and the silicon-aluminum ratios are 15, 20, and 35, namely USY15, USY20, and USY35;

[0039] C8-C18 long-chain olefins are produced by Maoming Branch of Sinopec;

[0040] Naphthalene was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., CAS No. 91-20-3;

[0041] Toluene was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., CAS No. 108-88-3;

[0042] Hydrogen peroxide was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., CAS No. 7722-84-1;

[0043] Oxalic acid was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., with a CAS number of 144-62-7;

[0044] (3-Mercaptopropyl)trimethoxysilane, mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethylsilane, and γ-mercaptopropyltriethoxysilane were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., with CAS numbers of 4420-74-0, 31001-77-7, 13399-93-4, and 14814-09-6, respectively;

[0045] Activated clay was purchased from MacLean Reagent Co., Ltd., with a CAS number of 70131-50-9 and a decolorization rate of ≥98%.

[0046] The conversion rate and selectivity of alkylnaphthalene were measured by gas chromatography. The instrument model was A90 from Zhejiang Fuli Co., Ltd., with FID detector, nitrogen carrier gas, injection volume of 2 μL, split ratio of 50:1, front inlet temperature of 280°C, and different heating programs were adopted according to different raw materials.

[0047] The kinematic viscosity and pour point of alkyl naphthalene lubricating oil are measured according to GB / T 265-1988 and GB / T3535-2006 standards respectively.

[0048] Preparation Example 1

[0049] A method for preparing a sulfonated USY15 molecular sieve comprises the following steps:

[0050] (1) Add the prepared 0.2 mol / L oxalic acid solution into a three-necked flask, then add USY15 molecular sieve, the ratio of USY15 molecular sieve to oxalic acid solution is 1 g: 25 mL, reflux at 80°C for 5 h and then centrifuge to obtain a solid product, wash the solid product with deionized water for 3 times until the washing liquid is neutral, dry at 105°C and then calcine in a muffle furnace at 550°C for 4 h to obtain oxalic acid-modified USY15 molecular sieve;

[0051] (2) 2 g of oxalic acid-modified USY15 molecular sieve was added to a 100 mL three-necked flask, 40 mL of toluene was added, the mixture was stirred and refluxed at 110° C. for 1 h, and then 1.6 g of (3-mercaptopropyl)trimethoxysilane was added, the mixture was stirred and refluxed under nitrogen protection for 24 h, and the mixture was filtered to obtain a mixture, and the mixture was washed with anhydrous ethanol for 3 times and dried at 60° C. to obtain a filter cake;

[0052] (3) Weigh 1 g of the filter cake dried in step (2) and add it to 60 mL of hydrogen peroxide. After stirring for 24 h, filter and wash the filter cake three times with deionized water. The filter cake is dried at 105° C. to obtain the sulfonated USY15 molecular sieve.

[0053] Preparation Example 2

[0054] A method for preparing a sulfonated USY20 molecular sieve comprises the following steps:

[0055] (1) Add the prepared 0.2 mol / L oxalic acid solution into a three-necked flask, then add USY20 molecular sieve, the ratio of USY20 molecular sieve to oxalic acid solution is 1 g: 25 mL, reflux at 80°C for 5 h and then centrifuge to obtain a solid product, wash the solid product with deionized water for 3 times until the washing liquid is neutral, dry at 105°C and then calcine at 550°C in a muffle furnace for 4 h to obtain oxalic acid-modified USY20 molecular sieve;

[0056] (2) Add 2 g of oxalic acid-modified USY20 molecular sieve to a 100 mL three-necked flask, add 40 mL of toluene, stir and reflux at 110° C. for 1 h, then add 1.6 g of (3-mercaptopropyl)trimethoxysilane, stir and reflux under nitrogen protection for 24 h, filter to obtain a mixture, wash the mixture with anhydrous ethanol 3 times, and dry at 60° C. to obtain a filter cake;

[0057] (3) Weigh 1 g of the filter cake dried in step (2) and add it to 60 mL of hydrogen peroxide. After stirring for 24 h, filter and wash the filter cake three times with deionized water. The filter cake is dried at 105° C. to obtain the sulfonated USY20 molecular sieve.

[0058] Preparation Example 3

[0059] A method for preparing a sulfonated USY35 molecular sieve comprises the following steps:

[0060] (1) Add the prepared 0.2 mol / L oxalic acid solution to a three-necked flask, then add USY35 molecular sieve, the ratio of USY35 molecular sieve to oxalic acid solution is 1 g / 25 mL, reflux at 80° C. for 5 h, and then centrifuge to obtain a solid product, wash the solid product with deionized water 3 times until the washing liquid is neutral, dry at 105° C., and then calcine at 550° C. in a muffle furnace for 4 h to obtain oxalic acid-modified USY35 molecular sieve;

[0061] (2) Add 2 g of oxalic acid-modified USY35 molecular sieve to a 100 mL three-necked flask, add 40 mL of toluene, stir and reflux at 110° C. for 1 h, then add 1.6 g of (3-mercaptopropyl)trimethoxysilane, stir and reflux under nitrogen protection for 24 h, filter to obtain a mixture, wash the mixture with anhydrous ethanol 3 times, and dry at 60° C. to obtain a filter cake;

[0062] (3) Weigh 1 g of the filter cake dried in step (2) and add it to 60 mL of hydrogen peroxide. After stirring for 24 h, filter and wash the filter cake three times with deionized water. The filter cake is dried at 105° C. to obtain the sulfonated USY35 molecular sieve.

[0063] Preparation Example 4

[0064] The difference from Preparation Example 1 is that the concentration of the oxalic acid solution in step (1) is 0.6 mol / L, and the other steps are the same as Preparation Example 1.

[0065] Preparation Example 5

[0066] The difference from Preparation Example 1 is that in step (2), an equal amount of γ-mercaptopropyltriethoxysilane is used to replace (3-mercaptopropyl)trimethoxysilane, and the other steps are the same as Preparation Example 1.

[0067] Example 1

[0068] A sulfonated USY molecular sieve is used in the catalytic preparation of long-chain alkyl naphthalene. The preparation method of long-chain alkyl naphthalene comprises the following steps:

[0069] (1) Naphthalene and 1-octene are added to a three-necked flask in a molar ratio of 2:1, stirred and heated to 90°C, and sulfonated USY15 molecular sieve is added to carry out alkylation reaction for 2 hours to obtain a crude product of alkylnaphthalene, wherein the mass of the sulfonated USY molecular sieve is 1% of the total mass of naphthalene and 1-octene;

[0070] (2) After cooling to room temperature, the obtained alkyl naphthalene crude product is filtered to remove the remaining sulfonated USY15 molecular sieve, and then the unreacted 1-octene and naphthalene are removed by vacuum distillation, followed by adding 4% activated clay, stirring at 80° C. for 50 min, and removing the clay to obtain the first alkyl naphthalene lubricating oil base oil;

[0071] (3) The first alkylnaphthalene lubricating oil base oil is further distilled at 180-190° C. to obtain a fraction which is a second alkylnaphthalene lubricating oil base oil.

[0072] According to the standards of GB / T 265-1988 and GB / T 3535-2006, the kinematic viscosity of the first alkyl naphthalene lubricant base oil and the second alkyl naphthalene lubricant base oil at a temperature of 100°C was measured. The kinematic viscosity of the first alkyl naphthalene lubricant base oil was 2.62 mm 2 / s, the pour point is -36°C; the kinematic viscosity of the second alkyl naphthalene lubricant base oil is 2.13 mm 2 / s, pour point is -40℃.

[0073] Comparative Example 1

[0074] The difference from Example 1 is that the catalyst added in step (1) is unmodified USY15 molecular sieve, and the other steps are the same as Example 1.

[0075] Comparative Example 2

[0076] The difference from Example 1 is that the catalyst added in step (1) is unmodified USY20 molecular sieve, and the other steps are the same as Example 1.

[0077] Comparative Example 3

[0078] The difference from Example 1 is that the catalyst added in step (1) is unmodified USY35 molecular sieve, and the other steps are the same as Example 1.

[0079] Comparative Example 4

[0080] The difference from Example 1 is that the catalyst added in step (1) is sulfonated USY20 molecular sieve, and the other steps are the same as Example 1.

[0081] Comparative Example 5

[0082] The difference from Example 1 is that the catalyst added in step (1) is sulfonated USY35 molecular sieve, and the other steps are the same as Example 1.

[0083] Comparative Example 6

[0084] The difference from Example 1 is that the catalyst added in step (1) is the catalyst obtained in Preparation Example 4, and the other steps are the same as Example 1.

[0085] Comparative Example 7

[0086] The difference from Example 1 is that the reaction temperature in step (1) is 70° C., and the other steps are the same as Example 1.

[0087] Comparative Example 8

[0088] The difference from Example 1 is that the reaction time in step (1) is 0.3 h, and the other steps are the same as Example 1.

[0089] Comparative Example 9

[0090] The difference from Example 1 is that the amount of sulfonated USY15 molecular sieve added in step (1) is 0.1% of the total mass of naphthalene and 1-octene, and the other steps are the same as in Example 1.

[0091] Comparative Example 10

[0092] The difference from Example 1 is that the catalyst added in step (1) is the catalyst of Preparation Example 5, and the other steps are the same as Example 1.

[0093] The conversion rate and selectivity results of 1-octene in Example 1 and Comparative Examples 1-10 are shown in Table 1.

[0094] Table 1

[0095]

[0096]

[0097] According to Table 1, Comparative Examples 1-3 respectively use unmodified USY15 molecular sieve, USY20 molecular sieve, and USY35 molecular sieve, and the conversion rates of 1-octene in Comparative Examples 1-3 are all lower than those in Example 1, indicating that the activity of unmodified USY molecular sieve is low. Comparative Examples 4 and 5 respectively use sulfonated USY20 molecular sieve and sulfonated USY35 molecular sieve, and the conversion rates of 1-octene are all lower than those in Example 1, indicating that only sulfonated USY15 molecular sieve has high activity, and USY molecular sieve can achieve the effect of the present application without using any silicon-aluminum ratio.

[0098] According to Comparative Examples 6-10 in Table 1, the concentration of the oxalic acid solution in Comparative Example 6 is too high, the reaction temperature in Comparative Example 7 is too low, and the reaction time in Comparative Example 8 is too short, and the conversion rate of 1-octene is lower than that in Example 1, indicating that the concentration of the oxalic acid solution, the reaction temperature, and the reaction time will affect the conversion rate of 1-octene. The amount of sulfonated USY15 added in Comparative Example 9 is too small, and the conversion rate of 1-octene is much lower than that in Example 1, indicating that the amount of sulfonated USY15 will affect the conversion rate of 1-octene. In Comparative Example 10, other thiol-containing siloxanes are used to react with oxalic acid-modified USY15 molecular sieves, and the catalytic activity of the prepared sulfonated USY15 molecular sieve is reduced, so that the conversion rate of 1-octene is lower than that in Example 1, indicating that not all siloxanes used to prepare sulfonated USY15 molecular sieves have high catalytic activity.

[0099] Example 2

[0100] A sulfonated USY molecular sieve is used in the catalytic preparation of long-chain alkyl naphthalene. The preparation method of long-chain alkyl naphthalene comprises the following steps:

[0101] (1) adding naphthalene and 1-decene in a molar ratio of 2:1 into a three-necked flask, stirring and heating to 100° C., adding sulfonated USY15 molecular sieve for alkylation reaction, the reaction time is 2 h, and obtaining a crude product of alkylnaphthalene, the mass of the sulfonated USY molecular sieve is 1.5% of the total mass of naphthalene and 1-decene;

[0102] (2) After cooling to room temperature, filtering the obtained alkylnaphthalene crude product to remove the remaining sulfonated USY15 molecular sieve, and then removing the unreacted 1-decene and naphthalene by vacuum distillation, then adding 5% activated clay, stirring at 80° C. for 60 minutes, and removing the clay to obtain the first decanylnaphthalene lubricating oil base oil;

[0103] (3) The first decanylnaphthalene lubricant base oil is further distilled at 180-190° C. to obtain a fraction which is a second decanylnaphthalene lubricant base oil.

[0104] According to the standards of GB / T 265-1988 and GB / T 3535-2006, the kinematic viscosity of the first decanalylnaphthalene lubricant base oil and the second decanalylnaphthalene lubricant base oil at a temperature of 100°C was measured. The kinematic viscosity of the first decanalylnaphthalene lubricant base oil was 3.31 mm 2 / s, the pour point is -40°C; the kinematic viscosity of the second decanalyl naphthalene lubricant base oil is 2.78 mm 2 / s, pour point is -43℃.

[0105] Example 3

[0106] The difference from Example 2 is that in step (1), the mass of the sulfonated USY15 molecular sieve catalyst is 3% of the total mass of naphthalene and long-chain olefins, the reaction time is 1.5 h, and the other steps are the same as in Example 2.

[0107] Example 4

[0108] The difference from Example 2 is that in step (1), the amount of sulfonated USY15 molecular sieve catalyst added is 6%, the reaction time is 50 min, and the other steps are the same as Example 2.

[0109] The conversion rate and selectivity results of 1-decene in Examples 2-4 are shown in Table 2.

[0110] Table 2

[0111]

[0112] Example 5

[0113] A sulfonated USY molecular sieve is used in the catalytic preparation of long-chain alkyl naphthalene. The preparation method of long-chain alkyl naphthalene comprises the following steps:

[0114] (1) Naphthalene and 1-dodecene were added to a three-necked flask in a molar ratio of 2:1, stirred and heated to 110°C, and sulfonated USY15 molecular sieve was added for alkylation reaction. The reaction time was 2 hours to obtain a crude product of alkylnaphthalene. The mass of the sulfonated USY15 molecular sieve was 1.5% of the total mass of naphthalene and 1-dodecene. The conversion rate of 1-dodecene was 98%, and the selectivity was 99%;

[0115] (2) After cooling to room temperature, the obtained alkylnaphthalene crude product is filtered to remove the remaining sulfonated USY15 molecular sieve, and then the unreacted 1-dodecene and naphthalene are removed by vacuum distillation, followed by adding 5% activated clay, stirring at 90° C. for 70 minutes, and removing the clay to obtain the first dodecylnaphthalene lubricating oil base oil;

[0116] (3) The first dodecylnaphthalene lubricant base oil is further distilled at 180-190° C. to obtain a fraction which is a second dodecylnaphthalene lubricant base oil.

[0117] According to the standards of GB / T 265-1988 and GB / T 3535-2006, the kinematic viscosity of the first dodecylnaphthalene lubricant base oil and the second dodecylnaphthalene lubricant base oil at a temperature of 100°C was measured. The kinematic viscosity of the first dodecylnaphthalene lubricant base oil was 4.22 mm 2 / s, the pour point is -38°C; the kinematic viscosity of the second dodecylnaphthalene lubricant base oil is 3.90 mm 2 / s, pour point is -40℃.

[0118] Example 6

[0119] A sulfonated USY molecular sieve is used in the catalytic preparation of long-chain alkyl naphthalene. The preparation method of long-chain alkyl naphthalene comprises the following steps:

[0120] (1) Naphthalene and 1-tetradecene were added to a three-necked flask in a molar ratio of 2:1, stirred and heated to 120°C, and sulfonated USY15 molecular sieve was added for alkylation reaction. The reaction time was 2 hours to obtain a crude product of alkylnaphthalene. The mass of the sulfonated USY15 molecular sieve was 1.5% of the total mass of naphthalene and 1-tetradecene. The conversion rate of 1-tetradecene was 98%, and the selectivity was 99%;

[0121] (2) After cooling to room temperature, the obtained alkylnaphthalene crude product is filtered to remove the remaining sulfonated USY15 molecular sieve, and then the unreacted 1-tetradecene and naphthalene are removed by vacuum distillation, followed by adding 5% activated clay, stirring at 90° C. for 70 minutes, and removing the clay to obtain the first tetradecylnaphthalene lubricating oil base oil;

[0122] (3) The first tetradecylnaphthalene lubricating oil base oil is further distilled at 180-200° C. to obtain a fraction which is a second tetradecylnaphthalene lubricating oil base oil.

[0123] According to the standards of GB / T 265-1988 and GB / T 3535-2006, the kinematic viscosity of the first tetradecyl naphthalene lubricant base oil and the second tetradecyl naphthalene lubricant base oil at a temperature of 100°C was measured. The kinematic viscosity of the first tetradecyl naphthalene lubricant base oil was 4.47 mm 2 / s, the pour point is -43°C; the kinematic viscosity of the second tetradecyl naphthalene lubricant base oil is 3.93 mm 2 / s, pour point is -46℃.

[0124] Example 7

[0125] A sulfonated USY molecular sieve is used in the catalytic preparation of long-chain alkyl naphthalene. The preparation method of long-chain alkyl naphthalene comprises the following steps:

[0126] (1) Naphthalene and 1-hexadecene were added to a three-necked flask in a molar ratio of 2:1, stirred and heated to 140°C, and sulfonated USY15 molecular sieve was added for alkylation reaction. The reaction time was 2 hours to obtain a crude product of alkylnaphthalene, the conversion rate of 1-hexadecene was 99%, and the selectivity was 99%; the mass of the sulfonated USY15 molecular sieve was 2% of the total mass of naphthalene and 1-hexadecene, the conversion rate of 1-hexadecene was 99%, and the selectivity was 99%;

[0127] (2) After cooling to room temperature, the obtained crude alkyl naphthalene product is filtered to remove the remaining sulfonated USY15 molecular sieve, and then the unreacted 1-hexadecene and naphthalene are removed by vacuum distillation, followed by adding 5% activated clay, stirring at 105° C. for 100 minutes, and after removing the clay, the first hexadecyl naphthalene lubricating oil base oil is obtained;

[0128] (3) The first hexadecylnaphthalene lubricating oil base oil is further distilled at 190-220° C. to obtain a fraction which is a second hexadecylnaphthalene lubricating oil base oil.

[0129] According to the standards of GB / T 265-1988 and GB / T 3535-2006, the kinematic viscosity of the first hexadecyl naphthalene lubricant base oil and the second hexadecyl naphthalene lubricant base oil at a temperature of 100°C was measured. The kinematic viscosity of the first hexadecyl naphthalene lubricant base oil was 5.03 mm 2 / s, the pour point is -36°C; the kinematic viscosity of the second hexadecyl naphthalene lubricant base oil is 4.29 mm 2 / s, pour point is -39℃.

[0130] Example 8

[0131] The difference from Example 7 is that the mass of the sulfonated USY15 molecular sieve in step (1) is 3% of the total mass of naphthalene and 1-hexadecene, the reaction time is 1.5 h, and the other steps are the same as Example 7.

[0132] Example 9

[0133] The difference from Example 7 is that the mass of the sulfonated USY15 molecular sieve in step (1) is 6% of the total mass of naphthalene and 1-hexadecene, the reaction time is 1.5 h, and the other steps are the same as Example 7.

[0134] Comparative Example 11

[0135] The difference from Example 7 is that the reaction temperature in step (1) is 120° C. and the reaction time is 2 h. The other steps are the same as Example 7.

[0136] Comparative Example 12

[0137] The difference from Example 7 is that in step (1), the reaction temperature in step (1) is 60° C., the reaction time is 2 h, and the other steps are the same as Example 7.

[0138] Comparative Example 13

[0139] The difference from Example 7 is that the catalyst added in step (1) is unmodified USY15 molecular sieve, the reaction is carried out for 2 hours, and the other steps are the same as Example 7.

[0140] Comparative Example 14

[0141] The difference from Example 7 is that the catalyst added in step (1) is unmodified USY20 molecular sieve, the reaction is carried out for 2 hours, and the other steps are the same as Example 7.

[0142] Comparative Example 15

[0143] The difference from Example 7 is that the catalyst added in step (1) is unmodified USY35 molecular sieve, the reaction is carried out for 2 hours, and the other steps are the same as Example 7.

[0144] The conversion rate and selectivity results of 1-hexadecene in Examples 7-9 and Comparative Examples 11-15 are shown in Table 3.

[0145] Table 3

[0146]

[0147] According to the comparison of Comparative Examples 11-12 in Table 3 with Example 7, it can be seen that the reaction temperature in Comparative Example 11 is too low, the reaction time in Comparative Example 12 is too long, and the conversion rate of 1-hexadecene is lower than that in Example 7, indicating that too low a reaction temperature or too long a reaction time will affect the conversion rate of 1-hexadecene.

[0148] According to the comparison of Comparative Examples 13-15 with Example 7, it can be found that when the unmodified USY molecular sieve is used as the catalyst, the conversion rate of 1-hexadecene is lower than that of Example 7, indicating that the activity of the unmodified USY molecular sieve is relatively low.

[0149] Example 10

[0150] A sulfonated USY molecular sieve is used in the catalytic preparation of long-chain alkyl naphthalene. The preparation method of long-chain alkyl naphthalene comprises the following steps:

[0151] (1) Naphthalene and 1-octadecene were added to a three-necked flask in a molar ratio of 3:1, stirred and heated to 160°C, and sulfonated USY15 molecular sieve was added for alkylation reaction. The reaction time was 2 hours to obtain a crude product of alkylnaphthalene. The mass of the sulfonated USY molecular sieve was 3% of the total mass of naphthalene and 1-octadecene. The conversion rate of 1-octadecene was 96%, and the selectivity was 98%;

[0152] (2) After cooling to room temperature, the obtained crude alkyl naphthalene product is filtered to remove the remaining sulfonated USY15 molecular sieve, and then the unreacted 1-octadecene and naphthalene are removed by vacuum distillation, followed by adding 8% activated clay, stirring at 115° C. for 120 min, and after removing the clay, the first octadecyl naphthalene lubricating oil base oil is obtained;

[0153] (3) The first octadecylnaphthalene lubricating oil base oil is further distilled at 200-230° C. to obtain a fraction which is a second octadecylnaphthalene lubricating oil base oil.

[0154] According to the standards of GB / T 265-1988 and GB / T 3535-2006, the kinematic viscosity of the first alkyl naphthalene lubricant base oil and the second alkyl naphthalene lubricant base oil at a temperature of 100°C was measured. The kinematic viscosity of the first alkyl naphthalene lubricant base oil was 5.43 mm 2 / s, the pour point is -41°C; the kinematic viscosity of the second alkyl naphthalene lubricant base oil is 4.70 mm 2 / s, pour point is -43℃.

[0155] Embodiment 11

[0156] The difference from Example 10 is that in step (1), naphthalene and 1-octadecene are added to a three-necked flask in a molar ratio of 3:1, stirred and heated to 140°C, and sulfonated USY15 molecular sieve is added for alkylation reaction. The reaction time is 2 hours to obtain a crude product of alkyl naphthalene, the mass of the sulfonated USY molecular sieve is 6% of the total mass of naphthalene and 1-octadecene, the conversion rate of 1-octadecene is 97%, and the selectivity is 99%. The other steps are the same as Example 10.

[0157] Example 12

[0158] The difference from Example 10 is that in step (1), naphthalene and 1-octadecene are added to a three-necked flask in a molar ratio of 2:1, stirred and heated to 160°C, and sulfonated USY15 molecular sieve is added for alkylation reaction. The reaction time is 2 hours to obtain a crude product of alkyl naphthalene, the mass of the sulfonated USY molecular sieve is 5% of the total mass of naphthalene and 1-octadecene, the conversion rate of 1-octadecene is 95%, and the selectivity is 98%. The other steps are the same as Example 10.

[0159] The sulfonated molecular sieve obtained in Example 7 was filtered and recovered after reaction, and used in a cyclic catalytic manner for 5 times. The conversion rate and selectivity of each time were statistically analyzed. The conversion rates of the five times were 99%, 99%, 98%, 97%, and 99%, respectively, and the selectivities were 99%, 98%, 99%, 99%, and 99%, respectively. This shows that the sulfonated USY molecular sieve of the present invention can be recycled for many times without significantly reducing the catalytic activity.

[0160] In summary, the sulfonated USY molecular sieve catalyst provided by the present invention catalyzes the alkylation reaction of long-chain olefins and naphthalene to prepare long-chain alkylnaphthalene, has high conversion rate and selectivity, can be recycled, can prepare two viscosities of alkylnaphthalene lubricating base oils, and is easy to operate for separating high-viscosity alkylnaphthalene lubricating base oils, and has certain industrial application value.

[0161] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A method for preparing a sulfonated USY molecular sieve, characterized in that: The following steps are involved: (1) adding a USY molecular sieve having a silicon-aluminum ratio of 8-35 to an acid solution having a concentration of 0.05-0.5 mol / L, the ratio of the USY molecular sieve to the acid solution being 1 g: (10-50) mL, the reaction temperature being 40-100° C., the reaction time being 2-5 h, and obtaining a solid product after the reaction, washing the solid product until the washing liquid is neutral, drying, and calcining to obtain an acid-modified USY molecular sieve; (2) adding the acid-modified USY molecular sieve to an organic solvent, stirring and refluxing at 80-130° C. for 0.5-2 h, then adding siloxane containing a mercapto group, refluxing under nitrogen protection, filtering to obtain a mixture, washing the mixture, and drying to obtain a filter cake; (3) adding hydrogen peroxide to the filter cake dried in step (2), mixing evenly, filtering, washing, and drying to obtain the sulfonated USY molecular sieve.

2. The method for preparing the sulfonated USY molecular sieve according to claim 1, characterized in that: The acid in step (1) is one of oxalic acid, citric acid, hydrochloric acid and sulfuric acid.

3. The method for preparing the sulfonated USY molecular sieve according to claim 1, characterized in that: In the step (2), the mass ratio of the acid-modified USY molecular sieve to the mercapto-containing siloxane is (0.2-1.6):

1.

4. The method for preparing the sulfonated USY molecular sieve according to claim 1, characterized in that: The mercapto-containing siloxane in step (2) is at least one of (3-mercaptopropyl)trimethoxysilane, 3-mercaptopropyltrimethylsilane, mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethylsilane.

5. The method for preparing the sulfonated USY molecular sieve according to claim 1, characterized in that: In the step (1), the solid product is calcined at a temperature of 400-650° C. and a calcination time of 2-4 hours.

6. The method for preparing the sulfonated USY molecular sieve according to claim 1, characterized in that: In the step (3), the ratio of the dried filter cake to hydrogen peroxide is 1 g: (20-100) mL.

7. A sulfonated USY molecular sieve, characterized in that: The sulfonated USY molecular sieve is prepared by the preparation method of any one of claims 1 to 6.

8. Use of the sulfonated USY molecular sieve as claimed in claim 7 in catalytic preparation of long-chain alkyl naphthalene, characterized in that: The preparation method of the long-chain alkyl naphthalene comprises the following steps: (1) adding sulfonated USY molecular sieve to naphthalene and long-chain olefins for alkylation reaction at a reaction temperature of 100-170° C. for a reaction time of 0.5-1.5 h to obtain a crude product of alkyl naphthalene; the molar ratio of naphthalene to the long-chain olefin is (1-3):1; the mass of the sulfonated USY molecular sieve is 0.3-6% of the total mass of the naphthalene and the long-chain olefin; (2) filtering the obtained alkyl naphthalene crude product, removing the incompletely reacted long-chain olefins and naphthalene by vacuum distillation, and then adding activated clay to decolorize the product at a temperature of 80-140° C. for a heating time of 20-120 min, and obtaining a first alkyl naphthalene lubricating oil base oil after decolorization; (3) The first alkylnaphthalene lubricating oil base oil is subjected to vacuum distillation at 180-230° C. to obtain a second alkylnaphthalene lubricating oil base oil.

9. The use of the sulfonated USY molecular sieve as claimed in claim 8 in catalytic preparation of long-chain alkyl naphthalene, characterized in that: The viscosity of the first alkyl naphthalene lubricant base oil in step (2) is 12-14 mm 2 / s, the viscosity of the second alkyl naphthalene lubricant base oil in step (3) is 1-3 mm 2 / s.

10. Use of the sulfonated USY molecular sieve according to claim 8 in catalytic preparation of long-chain alkyl naphthalene, characterized in that: The long-chain olefin in step (1) is C8-C 18 of linear α-olefins.

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