A sulfonated usy molecular sieve and use thereof in catalytically preparing long-chain alkyl naphthalenes

Abstract

The application discloses 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 sulfonated USY molecular sieve comprises the following steps: adding USY molecular sieve into an acid solution, obtaining a solid product after reaction, washing the solid product to be neutral, drying, and calcining to obtain acid-modified USY molecular sieve; adding the acid-modified USY molecular sieve into an organic solvent to react, then adding siloxane containing a mercapto group, refluxing under nitrogen protection, and obtaining a mixture of the siloxane containing the mercapto group and the USY molecular sieve after suction filtration; washing and drying the mixture to obtain a filter cake; uniformly mixing the filter cake after drying with hydrogen peroxide, suction filtering, washing, and drying to obtain the sulfonated USY molecular sieve. The sulfonated USY molecular sieve has good stability and catalytic performance, high conversion rate and selectivity of alkylation reaction, and can be repeatedly used.

Description

Technical Field

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

[0002] Alkylated naphthalenes (ANs) possess advantages such as high oxidative stability, high flash point, good thermal stability, and high safety. Long-chain ANs, in particular, offer excellent additive solubility, good demulsibility, and good compatibility. They play a crucial role in synthetic lubricants and are widely used in hydraulic fluids, gear oils, heat transfer fluids, transformer oils, refrigeration oils, compressor oils, and liquid crystals. ANs are produced by the alkylation reaction of single-component or multi-component mixtures of long-chain α-olefins with naphthalene in the presence of an acid catalyst. This reaction utilizes a carbonium ion mechanism. In the presence of an acidic catalyst, the olefin forms a carbonium ion, which then rearranges to form a carbonium ion at the α-n position, which then interacts with naphthalene to form ANs.

[0003] The traditional production of long-chain alkylnaphthalenes 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. These catalysts are severely corrosive to equipment, making separation of the product and catalyst difficult or costly, placing significant environmental pressures and failing to meet the requirements of green chemistry. Currently, the use of solid acid catalysts has drawbacks such as complex catalyst preparation, high costs, low processing capacity, poor activity and stability, and harsh reaction conditions. These factors lead to complex processes and high production costs, limiting 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 obtaining a high-viscosity component requires multiple distillations, which is cumbersome.

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

[0006] Patent CN114507110A discloses a method using trifluoromethanesulfonic acid and / or methanesulfonic acid as catalysts. By adding an extractant to separate unreacted raw materials and controlling the space velocity, continuous production of alkylnaphthalene is possible. However, because this method uses a liquid acid catalyst, post-reaction steps such as alkaline and water washing are required. Furthermore, liquid acid is highly corrosive to equipment, hindering long-term, continuous, and stable production in industrialized facilities.

[0007] Wang Guiru et al. reported the synthesis of long-chain alkylnaphthalenes using HY zeolite and compared the catalytic performance with that of β zeolite. They identified the optimal reaction temperature, catalyst particle size, and feed space velocity, achieving high olefin conversion and selectivity. The catalyst can be regenerated and reused. However, this method requires the addition of large amounts of cyclohexane as a solvent, which is not conducive to post-processing and is costly 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 alkylnaphthalenes. 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 pressurized. After the reaction is followed, a large amount of energy consumption is required to distill n-heptane, and the industrialization cost is high.

[0009] Therefore, the development of highly active solid acid catalysts for the alkylation of long-chain olefins with naphthalene to produce long-chain alkylnaphthalenes is in line with the concept of green environmental development, and exploring new catalyst reaction technologies is a current research priority. The development of highly active and stable heterogeneous solid acid catalysts for the alkylation of naphthalene with long-chain olefins has important application value. Summary of the Invention

[0010] The present invention aims to overcome the shortcomings of the prior art by providing a sulfonated USY molecular sieve and its use in the catalytic preparation of long-chain alkylnaphthalenes. This invention overcomes the problems of the prior art, such as the need for solvent addition, cumbersome product separation procedures, the tendency of liquid acid catalysts to corrode equipment, and non-compliance with green chemistry. Furthermore, the sulfonated USY molecular sieve, used as an alkylation catalyst, exhibits excellent stability and catalytic performance, resulting in high alkylation conversion and selectivity, good reproducibility, and reusability.

[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, wherein the ratio of the USY molecular sieve to the acid solution is 1 g: (10-50) mL, the reaction temperature is 40-100° C., and the reaction time is 2-5 h. After the reaction, a solid product is obtained, the solid product is washed until the washing liquid is neutral, dried, and calcined 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 a 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 filter cake dried in step (2) and mixing evenly, filtering, washing, and drying to obtain sulfonated USY molecular sieve.

[0016] In the present invention, a too high or too low silicon-to-aluminum ratio will affect the activity of the sulfonated USY molecular sieve. The concentration of the acid solution, the reaction temperature of the USY molecular sieve and the acid solution, and the reaction time will all affect the activity of the sulfonated USY molecular sieve, thereby affecting the olefin conversion rate. Therefore, the present invention improves the activity of the sulfonated USY molecular sieve by controlling the silicon-to-aluminum ratio of the USY molecular sieve, the concentration of the acid solution, the reaction temperature, and the reaction time within the above ranges.

[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 in step (1) is calcined at a temperature of 400-650° C. for 2-4 hours.

[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 the catalytic preparation of 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 into naphthalene and long chain olefin to carry out alkylation reaction, the reaction temperature is 100-170℃, the reaction time is 0.5-1.5h, the molar ratio of naphthalene to long chain olefin is (1-3):1, the mass of sulfonated USY molecular sieve is 0.3-6% of the total mass of naphthalene and long chain olefin;

[0026] (2) filtering the obtained crude alkyl naphthalene product, then removing the unreacted long chain olefin and naphthalene through vacuum distillation, then adding activated clay to carry out decolorization at a temperature of 80-140℃, the heating time is 20-120min, the first alkyl naphthalene lubricating oil base oil is obtained after decolorization;

[0027] (3) carrying out vacuum distillation on the first alkyl naphthalene lubricating oil base oil at 180-230℃, the second alkyl naphthalene lubricating oil base oil is obtained.

[0028] The present application can quickly separate the first alkyl naphthalene lubricating oil base oil by using excess naphthalene and sulfonated USY molecular sieve and long chain olefin, and removing the unreacted raw materials, and further distillation can still obtain the second alkyl naphthalene lubricating oil base oil.

[0029] The reaction temperature, reaction time and the ratio of sulfonated USY molecular sieve to naphthalene and long chain olefin will affect the conversion rate of olefin, therefore, the present application controls the reaction temperature, reaction time and the ratio of sulfonated USY molecular sieve to naphthalene and long chain olefin within the above range, which is beneficial to improve the conversion rate of olefin.

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

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

[0032] Compared with the prior art, the present application has the following advantages:

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

[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 are 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 base oil obtained by the present invention can be further distilled to obtain a low-viscosity alkyl naphthalene lubricating base oil. 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 with reference to 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., with silicon-aluminum ratios of 15, 20, and 35, namely USY15, USY20, and USY35;

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

[0040] Naphthalene was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. with a CAS number of 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 number 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 alkyl naphthalene were measured by gas chromatography. The instrument model was A90 from Zhejiang Fuli Co., Ltd., with an FID detector, nitrogen as the carrier gas, an injection volume of 2 μL, a split ratio of 50:1, a 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 sulfonated USY15 molecular sieve comprises the following steps:

[0050] (1) Add the prepared 0.2 mol / L oxalic acid solution to 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. The solid product is washed with deionized water three times until the washing liquid is neutral, dried at 105 ° C, and calcined 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, and the mixture was stirred and refluxed under nitrogen for 24 h. After filtration, the mixture was washed with anhydrous ethanol three 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 sulfonated USY20 molecular sieve comprises the following steps:

[0055] (1) Add the prepared 0.2 mol / L oxalic acid solution to 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. The solid product is washed with deionized water three times until the washing liquid is neutral, dried at 105 ° C, and calcined in a muffle furnace at 550 ° C for 4 h to obtain oxalic acid-modified USY20 molecular sieve;

[0056] (2) 2 g of oxalic acid-modified USY20 molecular sieve was added to a 100 mL three-necked flask, 40 mL of toluene was added, and the mixture was stirred and refluxed at 110 ° C for 1 h. Then, 1.6 g of (3-mercaptopropyl) trimethoxysilane was added, and the mixture was stirred and refluxed under nitrogen for 24 h. After filtration, the mixture was washed with anhydrous ethanol three times and dried 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 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. The solid product is washed with deionized water 3 times until the washing liquid is neutral, dried at 105 ° C, and calcined in a muffle furnace at 550 ° C for 4 h to obtain oxalic acid-modified USY35 molecular sieve;

[0061] (2) 2 g of oxalic acid-modified USY35 molecular sieve was added to a 100 mL three-necked flask, 40 mL of toluene was added, and the mixture was stirred and refluxed at 110 ° C for 1 h. Then, 1.6 g of (3-mercaptopropyl) trimethoxysilane was added, and the mixture was stirred and refluxed under nitrogen for 24 h. After filtration, the mixture was washed with anhydrous ethanol three times and dried 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 instead of (3-mercaptopropyl)trimethoxysilane, and the other steps are the same as Preparation Example 1.

[0067] Example 1

[0068] Use of a sulfonated USY molecular sieve in catalytically preparing long-chain alkyl naphthalene, a method for preparing long-chain alkyl naphthalene, comprising the following steps:

[0069] (1) naphthalene and 1-octene are added into a three-necked flask according to a molar ratio of 2:1, stirred and heated to 90°C, and a sulfonated USY15 molecular sieve is added for alkylation reaction, the reaction time is 2h, and a crude product of alkyl naphthalene is obtained, the mass of the sulfonated USY15 molecular sieve is 1% of the total mass of naphthalene and 1-octene;

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

[0071] (3) the first alkyl naphthalene lubricating oil base oil is continuously distilled at 180-190°C, and the obtained fraction is a second alkyl naphthalene lubricating oil base oil.

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

[0073] Comparative Example 1

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

[0075] Comparative Example 2

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

[0077] Comparative Example 3

[0078] The difference from Example 1 is that the catalyst added in step (1) is an unmodified USY35 molecular sieve, and the other steps are the same as those in 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 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] As shown in Table 1, Comparative Examples 1-3 use unmodified USY15 molecular sieve, USY20 molecular sieve, and USY35 molecular sieve, respectively. The conversion rates of 1-octene in Comparative Examples 1-3 are all lower than those in Example 1, indicating that the activity of the unmodified USY molecular sieve is low. Comparative Examples 4 and 5 use sulfonated USY20 molecular sieve and sulfonated USY35 molecular sieve, respectively. The conversion rates of 1-octene are all lower than those in Example 1, indicating that only the sulfonated USY15 molecular sieve has high activity, and the 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 was too high, the reaction temperature in Comparative Example 7 was too low, and the reaction time in Comparative Example 8 was too short, resulting in a lower conversion rate of 1-octene than in Example 1, indicating that the concentration of the oxalic acid solution, the reaction temperature, and the reaction time all affect the conversion rate of 1-octene. The amount of sulfonated USY15 added in Comparative Example 9 was too small, resulting in a much lower conversion rate of 1-octene than in Example 1, indicating that the amount of sulfonated USY15 used affects the conversion rate of 1-octene. In Comparative Example 10, other sulfhydryl-containing siloxanes were used to react with the oxalic acid-modified USY15 molecular sieve, resulting in a reduced catalytic activity of the sulfonated USY15 molecular sieve, resulting in a lower conversion rate of 1-octene than in Example 1, indicating that not all siloxanes used to prepare the sulfonated USY15 molecular sieve 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) Naphthalene and 1-decene were added to a three-necked flask in a molar ratio of 2:1, stirred and heated to 100°C, and sulfonated USY15 molecular sieve was 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 was 1.5% of the total mass of naphthalene and 1-decene;

[0102] (2) After cooling to room temperature, the obtained crude alkylnaphthalene product is filtered to remove the remaining sulfonated USY15 molecular sieve, and then the unreacted 1-decene and naphthalene are removed by vacuum distillation, followed by 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 decanethanaphthalene lubricating oil base oil is further distilled at 180-190° C. to obtain a fraction which is a second decanethanaphthalene lubricating oil base oil.

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

[0105] Example 3

[0106] The difference from Example 2 is that the mass of the sulfonated USY15 molecular sieve catalyst in step (1) 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 the addition amount of sulfonated USY15 molecular sieve catalyst in step (1) is 6%, the reaction time is 50 min, and the other steps are the same as Example 2.

[0109] The conversion 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 to carry out 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 crude alkylnaphthalene product was filtered to remove the remaining sulfonated USY15 molecular sieve, and then the unreacted 1-dodecene and naphthalene were removed by vacuum distillation. Subsequently, 5% activated clay was added, and the mixture was stirred at 90° C. for 70 minutes. After removing the clay, the first dodecylnaphthalene lubricating oil base oil was obtained;

[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 dodecyl naphthalene lubricant base oil is 3.90mm 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 to carry out 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 crude alkyl naphthalene 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 tetradecyl naphthalene 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] 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 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 was 4.47 mm 2 / s, the pour point is -43 ° C; the kinematic viscosity of the second tetradecyl naphthalene lubricant base oil is 3.93mm 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 to carry out 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 alkylnaphthalene 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 the addition of 5% activated clay, and stirring at 105° C. for 100 minutes. After removing the clay, the first hexadecylnaphthalene 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] 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 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 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 in 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 the reaction temperature in step (1) is 60° C. and the reaction time is 2 h. 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 h, 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 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, the reaction temperature in Comparative Example 11 was too low, the reaction time in Comparative Example 12 was too long, and the conversion rate of 1-hexadecene was lower than that in Example 7, indicating that too low a reaction temperature or too long a reaction time would 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 the conversion rates of 1-hexadecene using unmodified USY molecular sieve as catalyst are 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 to carry out 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 was filtered to remove the remaining sulfonated USY15 molecular sieve, and then the unreacted 1-octadecene and naphthalene were removed by vacuum distillation, followed by adding 8% activated clay, stirring at 115° C. for 120 minutes, and removing the clay to obtain the first octadecyl naphthalene lubricating oil base oil;

[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] 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 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 was 5.43 mm 2 / s, the pour point is -41 ° C; the kinematic viscosity of the second alkyl naphthalene lubricant base oil is 4.70mm 2 / s, pour point is -43℃.

[0155] Example 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 alkylnaphthalene, 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 in 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 alkylnaphthalene, 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 in Example 10.

[0159] The sulfonated molecular sieve obtained in Example 7 was filtered and recovered after the 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 5 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 multiple 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 alkylnaphthalenes with high conversion rate and selectivity, can be recycled, can prepare alkylnaphthalene lubricating base oils of two viscosities, and is easy to operate for separating the high-viscosity alkylnaphthalene lubricating base oil, and has certain industrial application value.

[0161] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method for preparing sulfonated USY molecular sieve, characterized in that: The following steps are involved: (1) Add USY molecular sieve with a silicon-aluminum ratio of 15 to an acid solution with a concentration of 0.05-0.5 mol / L, the ratio of USY molecular sieve to acid solution is 1 g: (10-50) mL, the reaction temperature is 80-100 ° C, the reaction time is 2-5 h, and a solid product is obtained after the reaction. The solid product is washed until the washing liquid is neutral, dried, and calcined to obtain an acid-modified USY molecular sieve; (2) Add the acid-modified USY molecular sieve to an organic solvent, stir and reflux at 80-130°C for 0.5-2h, then add the siloxane containing mercapto groups, reflux under nitrogen protection, filter to obtain a mixture, wash the mixture, and dry 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 sulfonated USY molecular sieve; 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; The mercapto-containing siloxane in step (2) is at least one of (3-mercaptopropyl)trimethoxysilane, mercaptopropylmethyldimethoxysilane, and 3-mercaptopropyltrimethylsilane.

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

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

5. 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 4.

6. Use of the sulfonated USY molecular sieve according to claim 5 in catalytic preparation of long-chain alkylnaphthalene, characterized in that: The preparation method of the long-chain alkyl naphthalene comprises the following steps: (1) Sulfonated USY molecular sieves are added to naphthalene and long-chain olefins for alkylation reaction at a reaction temperature of 140-170°C and a reaction time of 0.5-1.5 h to obtain a crude product of alkyl naphthalene; the molar ratio of naphthalene to long-chain olefin is (1-3):1; the mass of the sulfonated USY molecular sieve is 0.3-6% of the total mass of naphthalene and long-chain olefin; (2) filtering the obtained crude alkyl naphthalene product, removing the unreacted 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 20-120 minutes to obtain the first alkyl naphthalene lubricating oil base oil; (3) The first alkyl naphthalene lubricant base oil is subjected to vacuum distillation at 180-230° C. to obtain a second alkyl naphthalene lubricant base oil.

7. Use of the sulfonated USY molecular sieve according to claim 6 in catalytic preparation of long-chain alkylnaphthalene, 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 1-3mm 2 / s.

8. Use of the sulfonated USY molecular sieve according to claim 6 in catalytic preparation of long-chain alkylnaphthalene, characterized in that: The long chain olefin in step (1) is C8-C 18 of linear α-olefins.

Images