Raw material composition for organic synthesis reaction, application of raw material composition, hydrogenated terphenyl type synthetic heat-conducting oil and preparation method of hydrogenated terphenyl type synthetic heat-conducting oil

Abstract

The invention discloses a raw material composition for organic synthesis reaction and application thereof, hydrogenated terphenyl type synthetic heat conduction oil and a preparation method thereof, and the method comprises the following steps: carrying out transalkylation reaction on a mixed raw material in the presence of a catalyst, and collecting a fraction with a boiling point of 330 DEG C or above after the reaction; wherein the catalyst is an acidic molecular sieve catalyst; the mixed raw material contains cyclohexylbenzene, and methyl cyclopentylbenzene and / or biphenyl; wherein based on the total weight of the mixed raw materials, the content of cyclohexylbenzene is more than 50%, the content of methyl cyclopentylbenzene is less than 20%, and the content of biphenyl is less than 50%. The method provided by the invention has the advantages of simple preparation and low material consumption. The hydrogenated terphenyl type heat-conducting oil has the advantages of better heat stability, low-temperature fluidity and the like, can be directly used as high-temperature heat-conducting oil, and can also be used as a main component of other blended heat-conducting oil.

Description

Technical Field

[0001] The invention relates to a raw material composition for organic synthesis reaction and application thereof, and hydrogenated terphenyl type synthetic heat transfer oil and a preparation method thereof. Background Art

[0002] As a highly efficient heat transfer medium, high-temperature heat carrier (thermal oil) is widely used in industries such as petroleum and petrochemical, chemical industry, chemical fiber, papermaking, textile, food and solar thermal energy.

[0003] The research on heat transfer oil began in the 1930s. In 1929, Dow Chemical of the United States took the lead in developing a biphenyl-biphenyl ether mixture, named Dowtherm A, obtained patented technology and applied it to heating systems, thus pioneering the production of heat transfer oil and opening up a new path for the industrial development of heat transfer oil. After the 1960s, the United States, Japan, Germany and other countries successively launched heat transfer oil products with excellent performance. Among them, synthetic aromatic products have developed the fastest and are the most widely used. Such as alkylbenzene, alkylnaphthalene, alkylbiphenyl, dibenzyltoluene, hydrogenated terphenyl, etc., among which hydrogenated terphenyl is the preferred heat transfer oil for many high-temperature heat transfer devices due to its good high-temperature stability, low vapor pressure, and low coking tendency. Since the 1980s, with the rapid development of the domestic polyester industry, hydrogenated terphenyl has been promoted and applied in China, and extended to chemical fiber and other related petrochemical industries. At present, it has the highest proportion of use in high-temperature synthetic heat transfer oil.

[0004] The main component of hydrogenated terphenyl is a mixture of partially hydrogenated terphenyl isomers, which is obtained by partially hydrogenating a mixture of o-, m- and p-terphenyl in different proportions (saturation is 39%). It is a high-temperature liquid phase synthetic heat transfer oil with excellent thermal stability, oxidation resistance and low vapor pressure. It is widely used in petrochemical, synthetic fiber, synthetic resin, wood processing, nuclear fuel processing, medicine, printing and dyeing and other industries.

[0005] Hydrogenated terphenyl is mainly obtained by partial hydrogenation of a mixture of o-, m- and p-terphenyl (saturation 40%), and can also be obtained by benzene hydrogenation alkylation reaction, but the product yield is not high.

[0006] The basic raw material for the traditional preparation of hydrogenated terphenyl is pure benzene, which is made from the residue in the production process of refined biphenyl. At present, the "tubular method" is mostly used abroad, where benzene is passed through a red-hot pipe, and two benzene molecules each lose a hydrogen atom and combine with each other to produce biphenyl. This method of producing biphenyl through high-temperature cracking has an ideal conversion rate of only about 8-12%. When producing biphenyl, terphenyl is produced as a by-product. Terphenyl is hydrogenated to produce hydrogenated terphenyl. The terphenyl yield of this route is low, which seriously affects the supply of terphenyl, the raw material of hydrogenated terphenyl.

[0007] Domestic biphenyl production enterprises all produce biphenyl by condensing and dehydrogenating benzene vapor through a red-hot furnace tube. The production methods of different manufacturers are basically the same, but the heating methods are different, so there are significant differences in energy consumption and material consumption. The conversion rate of these traditional production processes is generally about 8-12%, and the output of terphenyl is about 10% of the biphenyl output. Due to the extremely low yield of terphenyl, the energy consumption and cost of hydrogenated terphenyl are high, and the production capacity is severely limited by terphenyl. Summary of the Invention

[0008] The object of the present invention is to overcome the problems of high deterioration rate, high pour point, and high low-temperature kinematic viscosity existing in synthetic oils in the prior art, and to provide a hydrogenated terphenyl-type synthetic heat transfer oil and a preparation method thereof. The synthetic heat transfer oil obtained by this method has the characteristics of low deterioration rate, low pour point, and low low-temperature kinematic viscosity.

[0009] After years of research and analysis, it is considered that thermal stability is the ability of heat transfer oil to resist chemical decomposition at high temperatures. It is the most important index among all technical indexes of high-temperature heat transfer oil, and it is the evaluation index for the service performance and safety performance that distinguishes it from other oils. It is the basis for determining the maximum allowable use temperature of heat transfer oil and classifying heat transfer oil products, and plays an indispensable and important role in the product type determination and category attribution of heat transfer oil. The high and low test temperature of thermal stability is the only test basis for measuring the high-temperature resistance performance of heat transfer oil, and it is also the most critical data and the most important basis for selecting the use temperature range of heat transfer oil. The deterioration rate is tested according to GB / T 23800 Determination Method for Thermal Stability of Organic Heat Carriers. After 1000h of thermal stability test, the national standard requires that the deterioration rate is less than 10%. A low deterioration rate indicates that the oil has excellent thermal stability, low deterioration rate and low loss during long-term use. The kinematic viscosity reflects the movement resistance of the oil and determines the fluidity and pumpability of the oil at a certain temperature, and has a direct relationship with the heat transfer effect of the heat transfer oil. The national standard stipulates that the kinematic viscosity of hydrogenated terphenyl at 40°C is not more than 40mm 2 / s.

[0010] In the first aspect of the present invention, a preparation method of a hydrogenated terphenyl-type synthetic heat transfer oil is provided. The method includes: performing a transalkylation reaction on a mixed raw material in the presence of a catalyst, and collecting the fraction with a boiling point above 330°C after the reaction; wherein, the catalyst is an acidic molecular sieve catalyst; the mixed raw material contains cyclohexylbenzene, and methylcyclopentylbenzene and / or biphenyl; wherein, based on the total weight of the mixed raw material, the content of cyclohexylbenzene is above 50%, the content of methylcyclopentylbenzene is below 20%, and the content of biphenyl is below 50%.

[0011] In the second aspect of the present invention, a hydrogenated terphenyl-type synthetic heat transfer oil synthesized by the method of the present invention is provided.

[0012] In the third aspect of the present invention, a raw material composition for organic synthesis reactions is provided. The composition contains cyclohexylbenzene, methylcyclopentylbenzene and / or biphenyl. Among them, based on the total weight of the composition, the content of cyclohexylbenzene is above 50%, the content of methylcyclopentylbenzene is below 20%, and the content of biphenyl is below 50%.

[0013] In the fourth aspect of the present invention, an application of the raw material composition of the present invention in the synthesis of heat transfer oil is provided.

[0014] The method of the present invention has the advantages of simple preparation and low material consumption.

[0015] The hydrogenated terphenyl type heat transfer oil of the present invention has better thermal stability, low temperature fluidity and other advantages, and can be directly used as high temperature heat transfer oil or as the main component of other blended heat transfer oils.

[0016] The preparation process of the method of the present invention is simple, the energy consumption and material consumption of the device are low, the product yield is greater than 95%, and the preparation method is safe and environmentally friendly. Specific Embodiments

[0017] The following provides a detailed description of the specific embodiments of the present invention. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0018] The present invention provides a method for preparing a hydrogenated terphenyl type synthetic heat transfer oil. The method includes: performing a transalkylation reaction on the mixed raw materials in the presence of a catalyst, and collecting the fraction with a boiling point above 330°C after the reaction; wherein, the catalyst is an acidic molecular sieve catalyst; the mixed raw materials contain cyclohexylbenzene, and methylcyclopentylbenzene and / or biphenyl; among them, based on the total weight of the mixed raw materials, the content of cyclohexylbenzene is above 50%, the content of methylcyclopentylbenzene is below 20%, and the content of biphenyl is below 50%. The method of the present invention has the advantages of simple preparation and low material consumption. The hydrogenated terphenyl type heat transfer oil of the present invention has a low deterioration rate, and has better thermal stability, low temperature fluidity and other advantages, and can be directly used as high temperature heat transfer oil or as the main component of other blended heat transfer oils.

[0019] According to a preferred embodiment of the present invention, based on the total weight of the mixed raw materials, the content of cyclohexylbenzene is 50-99.99%, the content of methylcyclopentylbenzene is 0.005-15%, and the content of biphenyl is 0.005-40%. Using the aforementioned preferred formula can synthesize a product with a low deterioration rate, and has better thermal stability, low temperature fluidity and other advantages.

[0020] According to a preferred embodiment of the present invention, based on the total weight of the mixed raw materials, the content of cyclohexylbenzene is 50-99%, the content of methylcyclopentylbenzene is 0.5-10%, and the content of biphenyl is 10-30%. Preferably, based on the total weight of the mixed raw materials, the content of cyclohexylbenzene is 70-80%, the content of methylcyclopentylbenzene is 5-10%, and the content of biphenyl is 15-20%. Using the aforementioned preferred formula can synthesize a product with a low deterioration rate and advantages such as better thermal stability and low-temperature fluidity.

[0021] According to a preferred embodiment of the present invention, the weight ratio of methylcyclopentylbenzene to cyclohexylbenzene is below 1:6; preferably below 1:8, more preferably below 1:10, and further preferably 1:50-1:10, such as 1:10, 1:15, 1:20, 1:25, 1:30, 1:35, etc. Using the aforementioned preferred formula can synthesize a product with a low deterioration rate and advantages such as better thermal stability and low-temperature fluidity.

[0022] In the present invention, the range of optional types of the acidic molecular sieve is relatively wide, and common acidic molecular sieves can all be used in the present invention. The following is a demonstration, but it does not limit the scope of the present invention accordingly.

[0023] For the present invention, preferably, the acidic molecular sieve catalyst is selected from 12-membered ring molecular sieves and / or solid superacids.

[0024] According to a preferred embodiment of the present invention, preferably, the 12-membered ring molecular sieve is selected from one or more of Y-type molecular sieves, Beta-type molecular sieves, and MWW-type molecular sieves.

[0025] According to an embodiment of the present invention, the solid superacid is, for example, sulfuric acid-supported zirconia.

[0026] According to a preferred embodiment of the present invention, the acidic molecular sieve catalyst is selected from one or more of USY, MCM-49, MCM-22, and SRZ-21.

[0027] According to a preferred embodiment of the present invention, preferably, the silicon-aluminum molar ratio of the acidic molecular sieve is 5-50. In the present invention, the silicon-aluminum molar ratio refers to the molar ratio of SiO 2 / Al 2 O 3 .

[0028] In the present invention, there are no special requirements for the operating conditions. The following is a demonstration, but it does not limit the scope of the present invention accordingly.

[0029] According to an embodiment of the present invention, the reaction conditions include: a temperature of 140-280°C, preferably 170-210°C.

[0030] According to an embodiment of the present invention, the reaction conditions include: a pressure of 0.2 to 3.0 MPa, preferably 0.5 to 1.5 MPa.

[0031] According to an embodiment of the present invention, the reaction conditions include: a space velocity of 0.1 to 10 h -1 , preferably 0.3 to 1 h -1 .

[0032] According to an embodiment of the present invention, the reaction conditions include: the method further includes: recycling the unreacted material back to the reaction solution for continued reaction.

[0033] The present invention provides a hydrogenated terphenyl-type synthetic heat transfer fluid obtained by the method described in the present invention. The hydrogenated terphenyl-type heat transfer fluid of the present invention has advantages such as better thermal stability and low-temperature fluidity, and can be directly used as a high-temperature heat transfer fluid or as the main component of other blended heat transfer fluids.

[0034] The present invention provides a raw material composition for organic synthesis reactions, which contains cyclohexylbenzene, methylcyclopentylbenzene and / or biphenyl. Among them, based on the total weight of the composition, the content of cyclohexylbenzene is above 50%, the content of methylcyclopentylbenzene is below 20%, and the content of biphenyl is below 50%; preferably, based on the total weight of the mixed raw materials, the content of cyclohexylbenzene is 50 to 99.99%, the content of methylcyclopentylbenzene is 0.005 to 15%, and the content of biphenyl is 0.005 to 40%; more preferably, based on the total weight of the mixed raw materials, the content of cyclohexylbenzene is 50 to 99%, the content of methylcyclopentylbenzene is 0.5 to 10%, and the content of biphenyl is 10 to 30%. Preferably, based on the total weight of the mixed raw materials, the content of cyclohexylbenzene is 70 to 80%, the content of methylcyclopentylbenzene is 5 to 10%, and the content of biphenyl is 15 to 20%; more preferably, the weight ratio of methylcyclopentylbenzene to cyclohexylbenzene is below 1:6; preferably below 1:8; more preferably 1:10 or less, and further preferably 1:50 - 1:10, such as 1:10, 1:15, 1:20, 1:25, 1:30, 1:35, etc. Using the aforementioned preferred formula can synthesize a product with a low deterioration rate and advantages such as better thermal stability and low-temperature fluidity.

[0035] The present invention provides the application of the raw material composition described in the present invention in the synthesis of heat transfer fluids.

[0036] The present invention will be described in detail below through examples. In the following examples, the physical property parameters were measured by the detection methods corresponding to GB-23971; the raw materials of cyclohexylbenzene and biphenyl were commercially available products, and methylcyclopentylbenzene was synthesized in the laboratory and obtained by rectification, with a purity greater than 99.5%.

[0037] The present invention will be described in detail below through examples, but the scope of the present invention is not limited thereby.

[0038] Example 1

[0039] Raw materials: 90% cyclohexylbenzene, 10% biphenyl;

[0040] Using USY (SiO₂ / Al₂O₃ molar ratio of 6.5) as the catalyst, at 170 °C, 0.5 MPa, and a space velocity of 0.5 h -1 , the fraction with a boiling point above 330 °C of the product was obtained by separation.

[0041] The results are shown in Table 1.

[0042] Example 2

[0043] Raw materials: 99% cyclohexylbenzene, 1% biphenyl.

[0044] The reaction conditions are the same as those in Example 1.

[0045] The results are shown in Table 1.

[0046] Example 3

[0047] Raw materials: 99% cyclohexylbenzene, 1% methylcyclopentylbenzene.

[0048] The reaction conditions are the same as those in Example 1.

[0049] The results are shown in Table 1.

[0050] Example 4

[0051] Raw materials: 95% cyclohexylbenzene, 5% methylcyclopentylbenzene.

[0052] Using MCM-22 (SiO₂ / Al₂O₃ molar ratio of 30) as the catalyst, at 195 °C, 1.0 MPa, and a space velocity of 0.5 h -1 , the fraction with a boiling point above 330 °C of the product was obtained by separation.

[0053] The results are shown in Table 1.

[0054] Example 5

[0055] Raw materials: 70% cyclohexylbenzene, 10% methylcyclopentane, 20% biphenyl;

[0056] Using MCM-49 (SiO₂ / Al₂O₃ molar ratio of 20) as the catalyst, at 190 °C, 1.0 MPa, and a space velocity of 0.3 h -1 , the fraction with a boiling point above 330 °C of the product was obtained by separation.

[0057] The results are shown in Table 1.

[0058] Example 6

[0059] Raw materials: 80% cyclohexylbenzene, 5% methylcyclopentylbenzene, 15% biphenyl.

[0060] Using MCM-22 (silicon-aluminum molar ratio of 30) as the catalyst, at 195 °C, 1.0 MPa, and a space velocity of 0.5 h -1 , the fraction of the product with a boiling point above 330 °C was separated.

[0061] The results are shown in Table 1.

[0062] Example 7

[0063] According to the method of Example 6, except that the raw materials were: 50% cyclohexylbenzene, 10% methylcyclopentylbenzene, and 40% biphenyl.

[0064] The results are shown in Table 1.

[0065] Example 8

[0066] According to the method of Example 6, except that the raw materials were: 99% cyclohexylbenzene, 0.5% methylcyclopentylbenzene, and 0.5% biphenyl.

[0067] The results are shown in Table 1.

[0068] Comparative Example 1

[0069] According to the method of Example 6

[0070] The raw materials were: 75% cyclohexylbenzene and 25% methylcyclopentylbenzene.

[0071] Using MCM-22 as the catalyst, at 195 °C, 1.0 MPa, and a space velocity of 0.5 h -1 , the fraction of the product with a boiling point above 330 °C was separated.

[0072] The results are shown in Table 1.

[0073] Comparative Example 2

[0074] According to the method of Example 6

[0075] The raw materials were: 65% cyclohexylbenzene, 25% methylcyclopentylbenzene, and 10% biphenyl.

[0076] Using MCM-22 as the catalyst, at 195 °C, 1.0 MPa, and a space velocity of 0.5 h -1 , the fraction of the product with a boiling point above 330 °C was separated.

[0077] The results are shown in Table 1.

[0078] Comparative Example 3

[0079] The raw materials were: 50% cyclohexylbenzene and 50% biphenyl;

[0080] The reaction conditions were the same as those in Example 6.

[0081] The results are shown in Table 1.

[0082] Comparative Example 4

[0083] Raw materials: 80% cyclohexylbenzene, 20% methylcyclopentylbenzene.

[0084] The reaction conditions are the same as those in Example 6.

[0085] The results are shown in Table 1.

[0086] Comparative Example 5

[0087] According to the method of Example 6, except that the raw materials are: 65% cyclohexylbenzene, 20% methylcyclopentylbenzene, and 15% biphenyl.

[0088] The results are shown in Table 1.

[0089] Comparative Example 6

[0090] Raw materials: 50% cyclohexylbenzene, 20% methylcyclopentylbenzene, and 30% biphenyl.

[0091] The reaction conditions are the same as those in Example 6.

[0092] The results are shown in Table 1.

[0093] Table 1

[0094]

[0095]

[0096] For the heat transfer oil of the present invention, the deterioration rate is all lower than 10%, meeting the national standard requirements. At the same time, the kinematic viscosity and pour point have obvious advantages compared with previous products.

[0097] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any suitable combination of each specific technical feature. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods. But these simple modifications and combinations should also be regarded as the content disclosed by the present invention and all fall within the protection scope of the present invention.

Claims

1. A preparation method of a hydrogenated terphenyl - type synthetic heat - transfer oil, characterized in that, the method comprises: subjecting a mixed raw material to a transalkylation reaction in the presence of a catalyst, and collecting the fraction with a boiling point above 330 °C after the reaction; wherein, the catalyst is an acidic molecular sieve catalyst; the mixed raw material contains cyclohexylbenzene, and methylcyclopentylbenzene and / or biphenyl; wherein, based on the total weight of the mixed raw material, the content of cyclohexylbenzene is above 50%, the content of methylcyclopentylbenzene is below 20%, and the content of biphenyl is below 50%.

2. The method according to claim 1, wherein, based on the total weight of the mixed raw material, the content of cyclohexylbenzene is 50 - 99.99%, the content of methylcyclopentylbenzene is 0.005 - 15%, and the content of biphenyl is 0.005 - 40%.

3. The method according to claim 1 or 2, wherein, based on the total weight of the mixed raw material, the content of cyclohexylbenzene is 50 - 99%, the content of methylcyclopentylbenzene is 0.5 - 10%, and the content of biphenyl is 10 - 30%; preferably, based on the total weight of the mixed raw material, the content of cyclohexylbenzene is 70 - 80%, the content of methylcyclopentylbenzene is 5 - 10%, and the content of biphenyl is 15 - 20%.

4. The method according to any one of claims 1 - 3, wherein, the weight ratio of methylcyclopentylbenzene to cyclohexylbenzene is below 1:6; preferably below 1:8; more preferably below 1:10; further preferably 1:50 - 1:

10.

5. The method according to any one of claims 1 - 4, wherein, the acidic molecular sieve catalyst is selected from dodecacyclic molecular sieves and / or solid superacids; preferably, the dodecacyclic molecular sieve is selected from one or more of Y - type molecular sieve, Beta - type molecular sieve, MWW - type molecular sieve; preferably, the solid superacid is sulfuric acid - supported zirconia.

6. The method according to any one of claims 1 - 5, wherein, the acidic molecular sieve catalyst is selected from one or more of USY, MCM - 49, MCM - 22, SRZ - 21; preferably, the silicon - aluminum molar ratio of the acidic molecular sieve is 5 - 50.

7. The method according to any one of claims 1 - 6, wherein, the reaction conditions include: The temperature is 140 to 280 °C, preferably 170 to 195 °C; the pressure is 0.2 to 3.0 MPa, preferably 0.5 to 1 MPa; the space velocity is 0.1 to 10 h -1 , preferably 0.3 to 1 h -1 ; and / or and / or the method further comprises: recycling the incompletely reacted material back to the reaction solution for continuous reaction.

8. A hydrogenated terphenyl - type synthetic heat - transfer oil synthesized by the method according to any one of claims 1 - 7.

9. A raw material composition for organic synthesis reactions, characterized in that, the composition contains cyclohexylbenzene, methylcyclopentylbenzene and / or biphenyl, wherein, based on the total weight of the composition, the content of cyclohexylbenzene is above 50%, the content of methylcyclopentylbenzene is below 20%, and the content of biphenyl is below 50%; preferably, based on the total weight of the mixed raw material, the content of cyclohexylbenzene is 50 - 99.99%, the content of methylcyclopentylbenzene is 0.005 - 15%, and the content of biphenyl is 0.005 - 40%; more preferably, based on the total weight of the mixed raw material, the content of cyclohexylbenzene is 50 - 99%, the content of methylcyclopentylbenzene is 0.5 - 10%, and the content of biphenyl is 10 - 30%. More preferably, based on the total weight of the mixed raw materials, the content of cyclohexylbenzene is 70-80%, the content of methylcyclopentylbenzene is 5-10%, and the content of biphenyl is 15-20%; More preferably, the weight ratio of methylcyclopentylbenzene to cyclohexylbenzene is below 1:6; preferably below 1:8; more preferably 1:10 or below; further preferably 1:50-1:

10.

10. Use of the raw material composition according to claim 9 in the synthesis of heat transfer oil.

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