CN115386395A - Method for reducing cloud point of Fischer-Tropsch synthetic oil and application of complexing agent and complexing agent - Google Patents

Abstract

The invention relates to the technical field of Fischer-Tropsch synthetic oil dewaxing technology, and discloses a method for reducing the cloud point of Fischer-Tropsch synthetic oil, a complexing agent and the application of the complexing agent. This complexing agent comprises component A and component B, and described component A is at least one in cellulose, glucose, urea, thiourea, acetamide, propionamide, and described component B is diatomaceous earth, At least one of clay, kaolin, titanium dioxide, and pseudo-boehmite; wherein, the mass ratio of component A:component B is (1‑50):1. It has the advantages of high dewaxing efficiency, no need to use activators and solvents, simple and easy process, can significantly reduce the cloud point of Fischer-Tropsch synthetic oil, and improve low-temperature fluidity.

Description

Method for reducing cloud point of Fischer-Tropsch synthetic oil and complexing agent and application of complexing agent

technical field

The invention relates to the technical field of Fischer-Tropsch synthetic oil dewaxing technology, in particular to a method for reducing the cloud point of Fischer-Tropsch synthetic oil, a complexing agent and the application of the complexing agent.

Background technique

For the oil produced by the Fischer-Tropsch synthesis process, its straight-chain hydrocarbon content usually reaches more than 90%, so it can be used as a raw material for high-quality diesel oil and lubricating oil base oil. Since the oil has the disadvantages of high freezing point and poor low-temperature fluidity, it is necessary to use isomerization technology to improve the properties of the oil. However, after the oil produced by the Fischer-Tropsch synthesis process undergoes isomerization treatment, there will still be n-paraffin residues in the product, resulting in a low decrease in the cloud point of the product oil and unsatisfactory low-temperature fluidity. Therefore, it must be dewaxed to reduce the cloud point.

CN104560195B discloses a kind of dewaxing method of isopropanol urea aqueous solution, the method comprises: after raw material oil and isopropanol urea aqueous solution are mixed, enter reactor to carry out complexation reaction, described reactor operates under reduced pressure condition, reactor top The gas-phase effluent is recycled back to the reactor after being cooled, part of the reaction product obtained at the bottom of the reactor is returned to the reactor, and the remaining part is decomplexed and settled in a washing tower for subsequent separation treatment, wherein the feed temperature of the reactor is 60 -80°C, the final reaction temperature is 20-32°C, and the operating pressure of the reactor is 22-50kPa. The method adopts isopropanol as cooling medium, utilizes isopropanol and water to vaporize and absorb heat when forming an azeotrope, and meets the requirement of multi-temperature complexation reaction, but the reactor needs to be depressurized.

CN102453548B discloses a solvent dewaxing method using a dewaxing aid, the method comprising: mixing molten dewaxing raw materials and a dewaxing aid, then adding a dewaxing solvent and cooling to the dewaxing temperature, and the solvent is added in the following manner: Multi-point dilution method, or one-time full dilution method, dewaxing oil and dewaxing wax paste can be obtained by filtration and separation at the dewaxing temperature. The dewaxing aid is any fraction of Fischer-Tropsch synthetic wax greater than 530 ° C. The solvent may be a C3-C6 aliphatic ketone or a mixture thereof, or a mixture of a ketone and a C6-C8 aromatic hydrocarbon. This method increases the filtration rate but involves the use of additives and solvents of the ketone and aromatic type.

CN101191083B discloses a method for reducing the cloud point of solvent dewaxed oil, the method comprising: a. mixing the waxy lubricating oil material with the dewaxing solvent, cooling to the filtration temperature, and filtering in a drum filter; b. The filtrate obtained in a is cooled to 1°C to 5°C lower than the filtration temperature of the drum filter, and sent to the tubular filter for secondary filtration; the filtrate is sent to the separation system to separate the dewaxing solvent from the dewaxing lubricating oil; c. After the differential force drop between the inlet and outlet of the type filter reaches the set value, stop the filtration, wash and dissolve the wax crystals on it with a dewaxing solvent, and mix the washing liquid with the waxy lubricating oil described in step a. This method requires the use of dewaxing solvents, a lengthy process, and specific requirements for filters.

To sum up, in the prior art, activators and organic dewaxing solvents generally need to be introduced in the dewaxing process, and there are strict requirements for the reaction or filtration process. In the subsequent steps, multiple distillations are required to remove the solvent and recover it. The process is lengthy, resulting in The cycle is long and the cost is high. Therefore, it is of great practical significance to provide a method with high dewaxing efficiency, simple process and easy implementation, and short treatment period.

Contents of the invention

The purpose of the present invention is to overcome the problems of high cloud point and poor low-temperature fluidity of the product oil caused by the residual n-alkanes still existing in the oil prepared by the Fischer-Tropsch synthesis process after the isomerization treatment, and the existing In solvent dewaxing technology, the solvent recovery process is complicated and the energy consumption is high. A method to reduce the cloud point of Fischer-Tropsch synthetic oil and the application of complexing agent and complexing agent are provided.

In order to achieve the above object, the first aspect of the present invention provides a complexing agent for reducing the cloud point of Fischer-Tropsch synthetic oil, the complexing agent comprises component A and component B, and said component A is cellulose, glucose , at least one of urea, thiourea, acetamide, and propionamide, and the component B is at least one of diatomite, clay, kaolin, titanium dioxide, and pseudoboehmite; wherein,

The mass ratio of component A:component B is (1-50):1.

A second aspect of the present invention provides a method for reducing the cloud point of Fischer-Tropsch synthetic oil, the method comprising:

(A) carry out complexation reaction with Fischer-Tropsch synthetic oil and complexing agent, obtain reaction product;

(B) carry out the first filtration separation to described reaction product, obtain dewaxed oil and wax paste;

Wherein, in step (A), the complexing agent is the complexing agent provided by the first aspect of the present invention.

The third aspect of the present invention provides the application of the complexing agent described in the aforementioned first aspect in reducing the cloud point of Fischer-Tropsch synthetic oil.

Through the above technical scheme, the method provided by the present invention has the following beneficial effects:

(1) There is no need to use activators and solvents in the dewaxing process, which avoids the process of multiple solvent recovery, thereby simplifying the process and reducing energy consumption;

(2) The high-efficiency separation of normal paraffins and isoparaffins in the Fischer-Tropsch synthetic oil treated by isomerization is realized, and the content of isoparaffins in the obtained dewaxed oil is higher than 98wt%;

(3) The cloud point of the Fischer-Tropsch synthetic oil can be significantly reduced. After being treated by the method of the present invention, the cloud point of the obtained dewaxed oil can be reduced to -30° C., and the low-temperature flow performance is greatly improved;

(4) It is not only suitable for removing residual n-alkanes in lubricating base oil prepared by isomerization of Fischer-Tropsch synthetic oil, but also can effectively reduce the cloud point of diesel and white oil products prepared from Fischer-Tropsch synthetic oil.

Detailed ways

Neither the endpoints nor any values of the ranges disclosed herein are limited to such precise ranges or values, and these ranges or values are understood to include values approaching these ranges or values. For numerical ranges, between the endpoints of each range, between the endpoints of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, these values Ranges should be considered as specifically disclosed herein.

Specific embodiments of the present invention will be described in detail below. It should be understood that the specific embodiments described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

The first aspect of the present invention provides a complexing agent for reducing the cloud point of Fischer-Tropsch synthetic oil, the complexing agent comprises component A and component B, and the component A is cellulose, glucose, urea, thiourea , at least one of acetamide, propionamide, the component B is at least one of diatomite, clay, kaolin, titanium dioxide, pseudo-boehmite; wherein,

The mass ratio of component A:component B is (1-50):1.

In the present invention, the inventors found that the use of a solid complexing agent comprising component A and component B can perform highly selective complexation with residual n-alkanes in Fischer-Tropsch synthetic oil after isomerization treatment reaction, the resulting dewaxed oil can be used for subsequent finishing, and the generated complex product can be heated and decomposed to obtain n-alkanes and solid complexing agents. Among them, n-alkanes can be recovered, and solid complexing agents can be added again To be recycled in the raw material oil to be processed. Applying the solid complexing agent to the complexation dewaxing of Fischer-Tropsch synthetic oil treated by isomerization can eliminate the use of activators and solvents in conventional dewaxing methods, avoiding the lengthy solvent recovery process, and through complexation The research on the specific component A, component B and dewaxing process conditions in the mixture can realize the efficient separation of normal paraffins and isoparaffins in the Fischer-Tropsch synthetic oil treated by isomerization, and the isomerization in the obtained dewaxed oil The content of alkane is higher than 98wt%, which greatly reduces the cloud point of the Fischer-Tropsch synthetic oil, and further improves the low-temperature fluidity.

In some embodiments of the present invention, the complexing agent comprises component A and component B, and the component A is preferably at least one of cellulose, glucose, urea, thiourea, acetamide, propionamide ; The component B is preferably at least one of diatomite, white clay, kaolin, titanium dioxide, and pseudo-boehmite; the mass ratio of the component A: is (1-50):1.

In the present invention, the complexing agent is solid, and its preparation process may include: (1) pulverizing the component A to obtain the component A powder, the particle size of the component A powder is preferably 100-200 mesh; (2) pulverize the component B to obtain the component B powder, the particle size of the component B powder is preferably 80-100 mesh; (3) the component A The powder is fully mixed with the component B powder, and then kneaded to form the complexing agent, wherein the mass ratio of the component A to the component B can be (1-50): 1 , the shape of the complexing agent can be one of spherical, clover, four-leaf and butterfly. The present invention has no special limitation on the pulverization and kneading molding in the preparation process of the complexing agent, and conventional pulverization and kneading molding methods in the art can be used.

In the present invention, in order to enable the complexing agent to have a better selective complexing effect on normal alkanes, thereby obtaining a better dewaxing effect, more preferably, the component A is cellulose, urea , at least one of thiourea, propionamide; said component B is at least one of clay, kaolin, titanium dioxide; said component A: the mass ratio of component B can be (2-40): 1;

Further preferably, the component A is at least one of urea, propionamide and thiourea, wherein thiourea accounts for 1/2-5/6 of the total mass of the component A; the component B is White clay and kaolin, wherein white clay accounts for 1/2-7/8 of the total mass of component B; the mass ratio of component A:component B is (15-30):1.

A second aspect of the present invention provides a method for reducing the cloud point of Fischer-Tropsch synthetic oil, the method comprising:

(A) carry out complexation reaction with Fischer-Tropsch synthetic oil and complexing agent, obtain reaction product;

(B) carry out the first filtration separation to described reaction product, obtain dewaxed oil and wax paste;

Wherein, in step (A), the complexing agent is the complexing agent provided in the first aspect of the present invention.

In some embodiments of the present invention, the Fischer-Tropsch synthetic oil is a product obtained by isomerization treatment of the oil prepared by the Fischer-Tropsch synthesis process, preferably with a cloud point of -30°C to 60°C. The isomerization treatment can adopt the conventional method in the art to carry out isomerization treatment to the oil product prepared by the Fischer-Tropsch synthesis process, for example, in the presence of a catalyst, the whole fraction including the Fischer-Tropsch hydrorefining tail oil At least one of the narrow fraction of Fischer-Tropsch hydrorefining tail oil and the full fraction of Fischer-Tropsch hydrocracking tail oil is subjected to isomerization treatment. Wherein, the catalyst includes at least one of ZSM-12, ZSM-22, ZSM-23, ZSM-48, SAPO-11 and catalysts supported by mordenite.

Preferably, the initial boiling point of the Fischer-Tropsch synthetic oil may be 150-200°C, and the final boiling point may be 650-700°C.

More preferably, the initial boiling point of the Fischer-Tropsch synthetic oil may be 180-200°C, and the final boiling point may be 650-680°C.

In some embodiments of the present invention, in step (A), the complexing reaction is preferably to add the complexing agent to the Fischer-Tropsch synthetic oil for thorough mixing and reaction. Wherein, the mass ratio of the Fischer-Tropsch synthetic oil:complexing agent may be (50-1):1, preferably (20-1):1.

In the present invention, in step (A), the conditions of the complexation reaction include: the temperature may be -5°C to 100°C, preferably -5°C to 80°C; the time may be 0.5-72h, preferably 1 -48h.

Preferably, in order to make the complexation reaction more fully, and then better separate the residual n-alkanes in the Fischer-Tropsch synthetic oil, the conditions of the complexation reaction also include stirring, and the stirring rate can be It is 30-800 rev/min, preferably 100-600 rev/min.

In some embodiments of the present invention, in step (B), the first filtration separation can adopt a conventional filtration separation method in the art, preferably one of suction filtration, pressure filtration and centrifugation. The temperature of the first filtration separation may be -35°C to 100°C.

Preferably, in order to obtain a better filtering and separating effect on the reaction product, the temperature of the first filtering and separating may be -35°C to 60°C.

In the present invention, after the first filtration and separation, the wax paste obtained is a complexation reaction product in the form of a white paste, and its main components include complexed normal alkanes, complexing agents and attached A small amount of isoparaffins; the obtained dewaxed oil is a product, wherein the content of isoparaffins is higher than 98wt%, and the content of residual normal paraffins is very low, which is similar to that of the Fischer-Tropsch synthetic oil before the method of the present invention is used. Compared with that, the cloud point of the dewaxed oil is greatly reduced, and then the low-temperature flow performance is greatly improved, which can meet the raw material index requirements of high-quality diesel oil and lubricating oil base oil.

In some embodiments of the present invention, preferably, the method for reducing the cloud point of Fischer-Tropsch synthetic oil further includes: successively heating and second filtering the wax paste to obtain normal alkanes and the complexing agent ; Wherein, the complexing agent is returned to step (A) for recycling.

In the present invention, the wax paste is heated for the purpose of decomposing the wax paste so as to release and recover the complexed n-alkanes therein. The heating can be done in a conventional manner in the art, which is not particularly limited in the present application. The heating conditions include: the temperature may be 80-200°C, and the time may be 1-72h; preferably, the temperature may be 80-180°C, and the time may be 2-48h.

In the present invention, the conditions for the second filtration and separation are not specifically limited, as long as the n-alkanes and the complexing agent can be fully separated.

In the present invention, the recycling can return the complexing agent obtained by the second filtration and separation to step (A) to be used alone as a dewaxing complexing agent, or it can be mixed with fresh complexing agent Common return step (A) uses as dewaxing complexing agent.

The third aspect of the present invention provides the application of the complexing agent described in the aforementioned first aspect in reducing the cloud point of Fischer-Tropsch synthetic oil.

The present invention will be described in detail below by way of examples. In the following examples and comparative examples,

The preparation process of complexing agent used in the present invention is as follows:

(1) Component A is placed in a pulverizer for pulverization to obtain component A powder with a particle size of 100-200 mesh;

(2) Component B is placed in a pulverizer for pulverization to obtain component B powder with a particle size of 80-100 mesh;

(3) Fully mix the component A powder and the component B powder respectively prepared above according to the mass ratio, and then knead them in a kneader to form a complexing agent.

The complexing agents used in Examples 1-11 (respectively denoted as L1-L11) were prepared by the above-mentioned process respectively, and the composition parameters of the complexing agents are shown in Table 1.

Table 1

The Fischer-Tropsch synthetic oil used was purchased from the coal-to-oil branch of Ningxia Coal Industry Group Co., Ltd. of the National Energy Group.

Example 1

(A) Add complexing agent L1 to Fischer-Tropsch synthetic oil (cloud point is 42°C, initial boiling point is 200°C, final boiling point is 650°C), and complexation reaction (Fischer-Tropsch synthesis) is carried out under stirring conditions. The mass ratio of oil:complexing agent L1 is 10:1), the reaction temperature is -5°C, the reaction time is 48h, and the stirring rate is 300 rpm to obtain the reaction product;

(B) performing the first filtration and separation of the reaction product at -35°C to obtain dewaxed oil P1 and wax paste;

(C) heating the wax paste at 80° C. for 2 hours, and then performing a second filtration separation to obtain normal alkanes and complexing agents. Recover the normal alkanes, and return the complexing agent to step (A) for recycling.

Example 2

According to the method of embodiment 1, the difference only lies in the use of complexing agent L2. Other conditions are identical with embodiment 1. Dewaxed oil P2 is obtained.

Example 3

According to the method of embodiment 1, the difference only lies in the use of complexing agent L3. Other conditions are identical with embodiment 1. Dewaxed oil P3 is obtained.

Example 4

(A) Add the complexing agent L4 to the Fischer-Tropsch synthetic oil (the cloud point is 23°C, the initial boiling point is 200°C, and the final boiling point is 680°C), and the complexation reaction (Fischer-Tropsch synthesis) is carried out under stirring conditions. The mass ratio of oil:complexing agent L4 is 20:1), the reaction temperature is 50°C, the reaction time is 10h, and the stirring rate is 600 rpm to obtain the reaction product;

(B) performing the first filtration and separation of the reaction product at 60°C to obtain dewaxed oil P4 and wax paste;

(C) heating the wax paste at 100° C. for 35 hours, and then performing a second filtration separation to obtain normal alkanes and complexing agents. Recover the normal alkanes, and return the complexing agent to step (A) for recycling.

Example 5

(A) Add the complexing agent L5 to the Fischer-Tropsch synthetic oil (the cloud point is -30°C, the initial boiling point is 180°C, and the final boiling point is 680°C), and the complexation reaction is carried out under stirring conditions (Fischer-Tropsch Synthetic oil: the mass ratio of complexing agent L5 is 1:1), the reaction temperature is 80°C, the reaction time is 1h, the stirring speed is 100 rpm, and the reaction product is obtained;

(B) performing the first filtration and separation of the reaction product at -5°C to obtain dewaxed oil P5 and wax paste;

(C) heating the wax paste at 150° C. for 48 hours, and then performing a second filtration separation to obtain normal alkanes and complexing agents. Recover the normal alkanes, and return the complexing agent to step (A) for recycling.

Example 6

(A) Add the complexing agent L6 to the Fischer-Tropsch synthetic oil (the cloud point is 60°C, the initial boiling point is 200°C, and the final boiling point is 660°C), and the complexation reaction (Fischer-Tropsch synthesis) is carried out under stirring conditions. The mass ratio of oil:complexing agent L6 is 5:1), the reaction temperature is 20°C, the reaction time is 25h, and the stirring rate is 500 rpm to obtain the reaction product;

(B) performing the first filtration and separation of the reaction product at -15°C to obtain dewaxed oil P6 and wax paste;

(C) heating the wax paste at 180° C. for 10 h, and then performing a second filtration separation to obtain normal alkanes and complexing agents. Recover the normal alkanes, and return the complexing agent to step (A) for recycling.

Example 7

(A) Add complexing agent L7 to Fischer-Tropsch synthetic oil (cloud point is -14 ° C, initial boiling point is 150 ° C, final boiling point is 650 ° C), and complexation reaction is carried out under stirring conditions (Fischer-Tropsch Synthetic oil: the mass ratio of complexing agent L7 is 30:1), the reaction temperature is 100°C, the reaction time is 50h, the stirring speed is 700 rpm, and the reaction product is obtained;

(B) performing the first filtration and separation of the reaction product at 100°C to obtain dewaxed oil P7 and wax paste;

(C) heating the wax paste at 90° C. for 20 h, and then performing a second filtration separation to obtain normal alkanes and complexing agents. Recover the normal alkanes, and return the complexing agent to step (A) for recycling.

Example 8

(A) Add the complexing agent L8 to the Fischer-Tropsch synthetic oil (the cloud point is 60°C, the initial boiling point is 160°C, and the final boiling point is 650°C), and the complexation reaction (Fischer-Tropsch synthesis) is carried out under stirring conditions. The mass ratio of oil:complexing agent L8 is 50:1), the reaction temperature is 40°C, the reaction time is 0.5h, and the stirring rate is 30 rpm to obtain the reaction product;

(B) performing the first filtration and separation of the reaction product at 60°C to obtain dewaxed oil P8 and wax paste;

(C) heating the wax paste at 200° C. for 1 hour, and then performing a second filtration separation to obtain normal alkanes and complexing agents. Recover the normal alkanes, and return the complexing agent to step (A) for recycling.

Example 9

(A) Add the complexing agent L9 to the Fischer-Tropsch synthetic oil (the cloud point is 15°C, the initial boiling point is 175°C, and the final boiling point is 650°C), and the complexation reaction (Fischer-Tropsch synthesis) is carried out under stirring conditions. The mass ratio of oil:complexing agent L9 is 25:1), the reaction temperature is 0°C, the reaction time is 20h, and the stirring rate is 400 rpm to obtain the reaction product;

(B) performing the first filtration and separation of the reaction product at 0°C to obtain dewaxed oil P9 and wax paste;

(C) heating the wax paste at 160° C. for 55 hours, and then performing a second filtration separation to obtain normal alkanes and complexing agents. Recover the normal alkanes, and return the complexing agent to step (A) for recycling.

Example 10

(A) Add complexing agent L10 to Fischer-Tropsch synthetic oil (the cloud point is -30°C, the initial boiling point is 160°C, and the final boiling point is 690°C), and the complexation reaction is carried out under stirring conditions (Fischer-Tropsch Synthetic oil: the mass ratio of complexing agent L10 is 40:1), the reaction temperature is 70°C, the reaction time is 72h, the stirring speed is 800 rpm, and the reaction product is obtained;

(B) performing the first filtration and separation of the reaction product at -35°C to obtain dewaxed oil P10 and wax paste;

(C) heating the wax paste at 120° C. for 72 hours, and then performing a second filtration separation to obtain normal alkanes and complexing agents. Recover the normal alkanes, and return the complexing agent to step (A) for recycling.

Example 11

(A) Add complexing agent L11 to Fischer-Tropsch synthetic oil (cloud point is 35°C, initial boiling point is 155°C, final boiling point is 700°C), and complexation reaction (Fischer-Tropsch synthesis) is carried out under stirring conditions. The mass ratio of oil:complexing agent L11 is 35:1), the reaction temperature is 20°C, the reaction time is 60h, and the stirring rate is 200 rpm to obtain the reaction product;

(B) performing the first filtration and separation of the reaction product at 10°C to obtain dewaxed oil P11 and wax paste;

(C) heating the wax paste at 110° C. for 60 h, and then performing a second filtration separation to obtain normal alkanes and complexing agents. Recover the normal alkanes, and return the complexing agent to step (A) for recycling.

Comparative example 1

According to the method of Example 1, the difference is that the mass ratio of component A in the complexing agent: component B is 60:1. Other conditions are identical with embodiment 1. Dewaxed oil D1 is obtained.

Comparative example 2

According to the method of Example 1, the difference is that the mass ratio of Fischer-Tropsch synthetic oil:complexing agent L1 is 55:1. Other conditions are identical with embodiment 1. A dewaxed oil D2 is obtained.

Comparative example 3

According to the method of Example 1, the difference is that the reaction temperature in step (A) is 110°C. Other conditions are identical with embodiment 1. Dewaxed oil D3 is obtained.

Comparative example 4

According to the method of Example 1, the difference is that the reaction time in step (A) is 0.2h. Other conditions are identical with embodiment 1. Dewaxed oil D4 is obtained.

Comparative example 5

According to the method of Example 1, the difference is that component B is not included in the complexing agent. Other conditions are identical with embodiment 1. A dewaxed oil D5 is obtained.

Comparative example 6

According to the method of Example 1, the difference is that component A is not included in the complexing agent. Other conditions are identical with embodiment 1. Dewaxed oil D6 is obtained.

Comparative example 7

Add the prepared dewaxing solution (urea:isopropanol:water mass ratio 5:4:1) to Fischer-Tropsch synthetic oil (cloud point 42°C, initial boiling point 200°C) at 50°C. The final boiling point is 650°C), wherein the mass ratio of Fischer-Tropsch synthetic oil: dewaxing liquid is 1:3. Stir at a stirring rate of 300 rpm and a temperature of 50°C for 48 hours, then filter and separate at -10°C to obtain dewaxed oil, alcohol aqueous solution and wax paste;

Heat the dewaxed oil to 90°C to remove isopropanol to obtain dewaxed oil D7; recover isopropanol from alcohol aqueous solution by distillation to obtain 85wt% isopropanol aqueous solution; add water to wax paste and heat to 80°C , to obtain aqueous urea and n-paraffins.

test case

The dewaxed oil (P1-P11, D1-D7) obtained in Examples 1-11 and Comparative Examples 1-7 was subjected to cloud point test and isoparaffin content test, and the cloud point of dewaxed oil was compared with dewaxing treatment Compared with the cloud point of the previous Fischer-Tropsch synthetic oil,

Cloud point: adopt automatic pour point cloud point measuring instrument to measure (manufacturer is Haierchao, model HCP-852);

Isoparaffin content: determined by gas chromatography (the manufacturer is Agilent, model 7890B).

The test results are shown in Table 2.

Table 2

Can find out by the result of embodiment 1-11 and comparative example, adopt complexing agent of the present invention and method to Fischer-Tropsch synthetic oil is processed, the obtained product dewaxed oil is compared with the Fischer-Tropsch synthetic oil before processing, The cloud point has been significantly reduced in different ranges, and then the low-temperature flow performance has been significantly improved. The specific performance is: for the raw material oil with higher cloud point (such as the Fischer-Tropsch synthetic oil used in Examples 1-3, 6 and 8) ), the cloud point appears to be significantly reduced after treatment; for the raw material oil with lower cloud point (such as the Fischer-Tropsch synthetic oil used in Examples 4, 9 and 11), the cloud point also significantly decreases after treatment; Feedstock oil with lower cloud point (such as the Fischer-Tropsch synthetic oil used in Examples 5, 7 and 10), although there is a certain gap between the decline in cloud point and the former two after treatment, in view of the fact that the cloud point of the feedstock oil itself has At a lower level, the effect of reducing the cloud point is also significant. In Examples 1-11, the content of isoparaffins in the obtained dewaxed oil can reach more than 98wt%, and the recovery rate of normal paraffins is high. However, Comparative Examples 1-7 did not use the complexing agent or method of the present invention. Compared with Example 1, the cloud point reduction and low-temperature fluidity improvement effect of the dewaxed oil obtained after treatment were not satisfactory.

In particular, Comparative Example 1, Comparative Example 5 and Comparative Example 6 did not use the complexing agent of the present invention, and the dewaxing effect was poor, resulting in lower cloud point reduction and isoparaffin content of the product dewaxed oil than in Example 1 Component B is not included in the complexing agent used in comparative example 5, and component A is not included in the complexing agent used in comparative example 6, and the cloud point reduction effect they obtain is all significantly lower than that of embodiment 1 (the complexing agent used Comprising component A and component B simultaneously in the mixture); Comparative example 7 has used the conventional solvent dewaxing method, and the cloud point reduction range and isoparaffin content of product dewaxed oil are obviously lower than embodiment 1, and the present application There is a significant difference in technical performance.

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 solution of the present invention, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the content disclosed in the present invention. All belong to the protection scope of the present invention.

Claims (10)

1. a complexing agent for reducing the cloud point of Fischer-Tropsch synthetic oil, characterized in that, the complexing agent comprises component A and component B, and said component A is cellulose, glucose, urea, thiourea , at least one of acetamide, propionamide, the component B is at least one of diatomite, white clay, kaolin, titanium dioxide, pseudo-boehmite; wherein, The mass ratio of component A:component B is (1-50):1. 2. complexing agent according to claim 1, wherein, described component A is at least one in cellulose, urea, thiourea, propionamide; The component B is at least one of clay, kaolin and titanium dioxide; The mass ratio of component A:component B is (2-40):1. 3. A method for reducing the cloud point of Fischer-Tropsch synthetic oil, characterized in that the method comprises: (A) carry out complexation reaction with Fischer-Tropsch synthetic oil and complexing agent, obtain reaction product; (B) carry out the first filtration separation to described reaction product, obtain dewaxed oil and wax paste; Wherein, in step (A), the complexing agent is the complexing agent described in claim 1 or 2. 4. The method according to claim 3, wherein, in step (A), the Fischer-Tropsch synthetic oil is the product obtained by the oil product prepared by the Fischer-Tropsch synthesis process through isomerization; Preferably, the cloud point of the Fischer-Tropsch synthetic oil is -30°C to 60°C; Preferably, the initial boiling point of the Fischer-Tropsch synthetic oil is 150-200°C, more preferably 180-200°C; the final boiling point of the Fischer-Tropsch synthetic oil is 650-700°C, more preferably 650-680°C . 5. The method according to claim 3 or 4, wherein, in step (A), the Fischer-Tropsch synthetic oil: the mass ratio of complexing agent is (1-50): 1, preferably (1-20 ):1. 6. The method according to any one of claims 3-5, wherein, in step (A), the conditions of the complexation reaction include: a temperature of -5°C to 100°C, preferably -5°C to 80°C; the time is 0.5-72h, preferably 1-48h; Preferably, the complexation reaction conditions further include stirring, and the stirring rate is 30-800 rpm, preferably 100-600 rpm. 7. The method according to any one of claims 3-6, wherein, in step (B), the conditions for the first filtration and separation include: a temperature of -35°C to 100°C, preferably -35°C to 60°C. 8. The method according to any one of claims 3-7, wherein the method further comprises: successively heating and second filtering and separating the wax paste to obtain normal alkanes and the complexing agent; Wherein, the complexing agent is returned to step (A) for recycling. 9. The method according to claim 8, wherein the heating conditions include: the temperature is 80-200°C, preferably 80-180°C; the time is 1-72h, preferably 2-48h. 10. the application of the complexing agent described in claim 1 or 2 in reducing the cloud point of Fischer-Tropsch synthetic oil.