CN115612480A - Carbon nano tube/perfluorosilane composite sol material and synthesis method and application thereof - Google Patents
Carbon nano tube/perfluorosilane composite sol material and synthesis method and application thereof Download PDFInfo
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Abstract
The invention provides a synthesis method of a carbon nano tube/perfluorosilane composite sol material, the carbon nano tube/perfluorosilane composite sol material and application thereof in preparation of a self-suspending proppant, wherein the method comprises the following steps: carrying out sol-gel reaction on a silicon source and fluoroalkyl alkoxy silane to prepare a sol solution of fluorinated silane; and mixing the fluorinated silane sol solution with the carbon nano tube with the hydroxylated surface to prepare the carbon nano tube/perfluorosilane composite sol material. Also provided is a self-suspending proppant and uses thereof, the method comprising: forming a coating on the surface of the quartz sand by using the carbon nano tube/perfluorosilane composite sol material; and heating the coated quartz sand in vacuum to obtain the self-suspending proppant. The composite material disclosed by the invention is hydrophobic and oleophobic, is easy to coat on the surface of a propping agent, is difficult to normally sink, reduces the flow resistance and realizes a long-term stable yield effect.
Description
Technical Field
The invention relates to the field of fracturing fracture proppants in the petroleum industry, relates to a technology of a modified amphiphobic coating of a hydroxylated carbon nanotube, and particularly relates to a synthesis method of a carbon nanotube/perfluorosilane composite sol material with a self-suspending function, the carbon nanotube/perfluorosilane composite sol material prepared by the method and application thereof in preparation of a self-suspending proppant, a preparation method of the self-suspending proppant and the self-suspending proppant prepared by the method.
Background
Currently, as a necessary material in fracturing, a variety of series such as a quartz sand series and a ceramsite series have been developed, and in addition, in order to increase a transport distance and a supporting height in a longitudinal direction of a proppant, an ultra-low density proppant has been developed. But the application at high closure stresses is greatly limited, as the lower the density, the lower the compression resistance. In order to solve the problem, the self-suspending proppant with low settling velocity and good supporting effect is developed by combining the characteristics of the fracturing fluid and the common proppant. The self-suspension function of the propping agent is improved as much as possible, the length and the height of the propping seams can be improved, more propping seams can enter the steering branch cracks, and the self-suspension propping agent is of great importance for improving the overall modification volume of the cracks and the stable yield effect after pressing. In addition, the self-suspending proppant has a certain promotion effect on the balanced extension and control of multiple fractures because the self-suspending proppant is not easy to settle at the bottom of a horizontal well bore or a fracture.
Chinese patent application CN 111088030A, "a fracturing used self-suspension proppant and its preparation method" relates to a polymer coating self-suspension proppant, mainly uses the hydrophilic groups in the polymer shell, such as carboxyl, amide group, sulfonic acid group, etc., to make a large amount of water molecules enter the interior of the polymer structure, thereby increasing the water absorption of the coated proppant shell layer, and to prop open the flexible molecular chain, so that the proppant volume is increased, thereby improving the suspension performance of the proppant in water. The focus is on the hydrophilic and supporting properties of the film itself. However, the water-swellable polymer material equivalently increases the drainage volume of the proppant, so that the water-swellable polymer material has a certain effect of damaging the flow conductivity of the proppant and is not beneficial to degradation and flowback at the later stage of construction. In addition, in the case of high sand-to-liquid ratio construction, there is a high possibility that the application is limited due to high friction resistance.
Chinese patent application CN 110358523A, "a special polymer for self-suspending proppant and its application" provides a design idea of a hydrophobically associating polymer for self-suspending proppant coating. Compared with the supporting volume formed by simple physical winding among chain segments of the common water-soluble polymer in water, the hydrophobic association polymer mainly depends on a network structure generated by hydrophobic association bonds, although the hydrophobic association polymer has unique rheological characteristics, and the supporting strength is obviously improved. However, at the same time, the apparent viscosity of the hydrophobically associative polymer is also much higher, which is not conducive to flowback after completion of fracturing.
Zhou Shanshan provides a design idea of hydroxylation of the surface of a carbon nanotube in a document [ research on synthesis of a hydroxylated carbon nanotube/polysilane composite material [ D ].2013, harbin university ], and polysilane is grafted on the surface of the carbon nanotube by a Grafting-From method to obtain a polysilane/carbon nanotube composite.
The document Jie Dong, colorful Superporous Coatings with Low slip Coatings and High Dual Based on Natural nanorods, ACS Applied Materials & Interfaces, 2017, volume 9 (1941-1952) provides a process for the preparation of a colored amphiphobic coating with Low interfacial tension and High Durability by a technique of compounding Natural Palygorskite (PAL) nanorods with organosilanes. The superhydrophobicity of the coating depends on, among other things, the surface morphology and chemical composition of the coating, and can be adjusted by the concentrations of PAL and organosilane. The coating exhibits high mechanical, environmental, chemical and thermal durability even under harsh conditions. The principle is to prepare different color coatings with amphiphobic and durable properties by adding different cationic dyes to various substrates by the same method.
In summary, the conventional method for manufacturing the self-suspending proppant mainly coats a water-swellable polymer material on the surface of the proppant, which is equivalent to increase the drainage volume of the proppant, thereby realizing the near-equilibrium effect of buoyancy and gravity. The proppant is applied to oil fields on a certain scale, but the high polymer materials used for coating have certain damage effect on the flow conductivity of the proppant, so that the proppant cannot be completely degraded and flowback after fracturing is finished. In addition, during high sand-to-liquid ratio construction, friction resistance is a problem which is not negligible in the construction process, a traditional propping agent generally has a water-wet characteristic, and the resistance is relatively large in the flowback process after pressing, so that the flowback rate can be reduced to a certain extent. In the production process after the oil gas is pressed, the oil gas is slowly converted into oil moisture due to the long-time soaking and scouring of the oil gas, so that the flow resistance of the oil gas is relatively large. It is clear that the existing self-suspending proppants have not been improved in any way in this respect to reducing the friction resistance.
Therefore, in view of the above two problems, there is a need to develop a novel self-suspending proppant to solve the limitations of the existing self-suspending proppant.
Disclosure of Invention
In view of this, in order to solve at least one of the above problems in the prior art, the present invention provides a carbon nanotube/perfluorosilane composite sol material, and a synthesis method and an application thereof, the carbon nanotube/perfluorosilane composite sol material of the present invention is coated on a surface of a support agent, is hydrophobic and oleophobic, can reduce flow resistance, realizes a longer-term stable yield effect, and can further improve young's modulus, tensile strength and fracture toughness of the coated support agent.
In a first aspect, the invention provides a method for synthesizing a carbon nanotube/perfluorosilane composite sol material. The carbon nano tube/perfluorosilane composite sol material can be used for coating a propping agent.
As a specific embodiment of the present invention, the synthesis method comprises the steps of:
(1) Carrying out sol-gel reaction on a silicon source and fluoroalkyl alkoxy silane to prepare a sol solution of fluorinated silane;
(2) And mixing the sol solution of fluorinated silane with the carbon nano tube with the hydroxylated surface to prepare the carbon nano tube/perfluorosilane composite sol material.
Optionally, the preparation method of the surface hydroxylated carbon nanotube includes: adding strong base into the carbon nano tube, treating the carbon nano tube by adopting high-energy ball milling, and washing and drying the carbon nano tube.
In the present invention, the term "high energy ball milling" refers to a method of pulverizing a powder into nano-sized particles or mixing by using rotation or vibration of ball milling to make hard balls (e.g., steel balls) collide with a raw material, grind and stir it.
Preferably, the strong base is an alkali metal hydroxide, preferably at least one of potassium hydroxide and sodium hydroxide; and/or the carbon nanotubes are multi-walled carbon nanotubes; and/or the weight ratio of the carbon nanotubes to the strong base is 10 to 60, 30 to 50, for example 40; and/or the ball milling time is 30-35 hours; and/or ethanol is used as a ball milling medium, and the ratio of the volume of the ethanol to the mass of the carbon nano tubes is 4-6 ml/g.
In step 1), the silicon source is tetraethoxysilane and/or
The fluoroalkyl group of the fluoroalkyl alkoxy silane is a C6-C12 fluoroalkyl group having 10-20 fluorine atoms, and is preferably a C8-C12 fluoroalkyl group having 12-17 fluorine atoms; and/or the alkoxy group is a C1-C6 alkoxy group, preferably a C1-C3 alkoxy group, for example a methoxy or ethoxy group.
Preferably, the fluoroalkylalkoxysilane is heptadecafluorodecyltriethoxysilane, perfluorooctyltrimethoxysilane, or dodecafluoroheptylpropyltrimethoxysilane; and/or
The weight ratio of the surface hydroxylated carbon nanotube, the silicon source and the fluoroalkyl alkoxy silane is 10-30 and is (400-600) as follows, and/or the temperature of sol-gel reaction is 80-100 ℃, and/or the surface hydroxylated carbon nanotube is mixed with the sol solution of the fluorinated silane in the form of dispersion liquid according to the mass ratio of 1-3:6-10, wherein the dispersion liquid contains 10-30 g of the surface hydroxylated carbon nanotube and 700-1300 ml of ethanol.
In a second aspect, the present invention provides a carbon nanotube/perfluorosilane composite sol material prepared according to the synthesis method of any one of the embodiments of the first aspect of the present invention.
In a third aspect, the present invention provides a carbon nanotube/perfluorosilane composite sol material prepared according to the synthesis method of any one of the embodiments of the first aspect of the present invention or a carbon nanotube/perfluorosilane composite sol material according to the second aspect of the present invention for use in preparing a self-suspending proppant.
In a third aspect, the present invention provides a self-suspending proppant.
In a specific embodiment, the self-suspending proppant comprises quartz sand and a coating film formed by the carbon nanotube/perfluorosilane composite sol material prepared according to the synthesis method of any one of the first aspect of the invention or the carbon nanotube/perfluorosilane composite sol material according to the second aspect of the invention.
In a fourth aspect, the invention provides a preparation method of a self-suspending proppant.
In a specific embodiment, the preparation method comprises the following steps:
1) Forming a coating film on the surface of quartz sand on the carbon nanotube/perfluorosilane composite sol material prepared by the synthesis method according to any one of the first aspect of the present invention or the carbon nanotube/perfluorosilane composite sol material according to the second aspect of the present invention;
2) And (3) heating the quartz sand coated with the carbon nano tube/perfluorosilane composite sol material in vacuum to obtain the self-suspending proppant.
Preferably, the coating is formed on the surface of quartz sand by mixing the carbon nanotube/perfluorosilane composite sol material with heated quartz sand, wherein the mass ratio of the carbon nanotube/perfluorosilane composite sol material to the quartz sand is 1-10, preferably 5-10; or the carbon nano tube/perfluorosilane composite sol material is used for spraying quartz sand.
Preferably, the heating temperature of the quartz sand is 100-150 ℃; the temperature during spraying is 80-90 ℃.
Optionally, heating the coated quartz sand particles at 160-180 ℃ for 5-6 hours in vacuum.
The invention has the following advantages:
(1) The proppant in the prior art has relatively large resistance in the flowback process after being pressed, and can reduce the flowback rate to a certain extent. Compared with the prior art, the carbon nano tube/perfluorosilane composite sol material disclosed by the invention is hydrophobic and oleophobic, is easy to coat on the surface of a propping agent, has a super-hydrophobic characteristic, can make a liquid-solid interface difficult to completely contact in a fracturing sand adding process, and forms an effect similar to a buoyancy liquid film around the propping agent so that the propping agent is difficult to normally sink. And for the oleophobic characteristic, the flow resistance can be greatly reduced in the production process after pressing, so that the long-term stable production effect can be realized. The carbon nano tube/perfluorosilane composite sol material can modify the micro-nano microstructure on the surface of the proppant, and the modification does not damage the original structural strength of the proppant.
(2) The carbon nanotube/perfluorosilane composite sol material adopts a Carbon Nanotube (CNT) technology, and when the surface of the proppant is modified, the CNT is considered to have excellent physical and mechanical properties and interface properties, so that the Young modulus, tensile strength and fracture toughness of the coated proppant can be improved while a microstructure is introduced.
Drawings
FIG. 1 is a schematic diagram of a process for hydroxylating the surface of a carbon nanotube using a strong base;
fig. 2 is a schematic diagram of a process for modifying the surface of a carbon nanotube by using a hydrophobic and oleophobic group.
Detailed Description
The present invention is further illustrated by the following examples, which are not to be construed as limiting the invention in any way.
1. Preparing the carbon nano tube/perfluorosilane composite sol material for coating the propping agent.
1) Preparing the surface hydroxylated carbon nano tube by adopting a technology combining strong base addition and high-energy ball milling:
40g of multi-walled carbon nanotubes and 1000g of potassium hydroxide were added to a laboratory ball mill, and about 200ml of ethanol was added thereto, and ball-milled for 30 to 35 hours. After ball milling was completed, the reactants were washed with deionized water to neutral pH. Then the reactant is put into a vacuum drying oven and dried for 20 to 24 hours at 120 to 150 ℃ (preferably 140 ℃) to obtain the carbon nano tube with the hydroxylated surface.
2) Preparing a carbon nano tube/perfluorosilane composite sol material:
in water bath, 20g of carbon nano tube with hydroxylated surface is added into 1000ml of ethanol for ultrasonic dispersion for 3-5 hours to prepare ethanol dispersion liquid of the carbon nano tube. A sol solution of fluorinated silane is prepared by mixing 500g of ethyl orthosilicate and 500g of a fluoroalkylalkoxysilane such as heptadecafluorodecyltriethoxysilane, tridecafluorooctyltrimethoxysilane or dodecafluoroheptylpropyltrimethoxysilane, etc., preferably tridecafluorooctyltrimethoxysilane, and adding 3000ml of water and 2000ml of ethanol to the mixture to continuously conduct a sol-gel reaction at 80 to 100 ℃. And then mixing the fluorinated silane sol solution with the carbon nanotube ethanol dispersion liquid according to the mass ratio of 8:2 to obtain the carbon nanotube/perfluorosilane composite sol material for coating the propping agent, wherein the carbon nanotube/perfluorosilane composite sol material is a amphiphobic composite material.
2. Self-suspending proppants were prepared.
1) Washing 10-20 mesh quartz sand with ethanol and water, and air drying at 60-80 deg.C for 2-3 hr.
2) In ethanol water solution, heating the quartz sand after cleaning and air drying to 100-150 ℃, and adding a carbon nano tube/perfluorosilane composite sol material under stirring, wherein the mass ratio of the carbon nano tube/perfluorosilane composite sol material to the quartz sand is 1-10. Or the surface of the quartz sand can be coated by adopting a spraying method at the temperature of 80-90 ℃. It is believed that the amphiphobic composite can be copolymerized to the quartz sand surface through Si-O-Si bonds.
3) The prepared quartz sand particles coated with the carbon nano tube/perfluorosilane are heated for 5 to 6 hours in vacuum at the temperature of between 160 and 180 ℃, residual chemical substances (ethanol, water, unreacted tetraethoxysilane, tridecafluorooctyltrimethoxysilane and the like) can be removed, and sol coating is cured.
4) And filtering, cooling, crushing and sieving the quartz sand to obtain the proppant coated with the carbon nano tube/perfluorosilane composite material.
Example 1
Raw materials: multi-walled carbon nanotubes (Sigma-Aldrich multi-walled carbon nanotubes), potassium hydroxide (analytical grade), ethanol, ethyl orthosilicate, tridecafluorooctyltrimethoxysilane, quartz sand, pH test paper and the like;
quartz sand: the grain size range is 10-20 meshes;
the preparation method comprises the following steps:
1) 40g of multi-walled carbon nanotubes and 1000g of potassium hydroxide were added in a laboratory ball mill and about 200ml of ethanol were added and ball milled for 30 hours.
2) After ball milling was complete, all reactants were washed with deionized water to neutral pH.
3) And (3) putting the neutral carbon nano tube sample into a vacuum drying oven, and drying for 24 hours at 140 ℃ to obtain the carbon nano tube with the surface hydroxylated.
4) 20g of the carbon nano tube with the hydroxylated surface is taken to be dispersed in 1000ml of ethanol in a water bath for 4 hours by ultrasonic.
5) 500g of ethyl orthosilicate, 500g of tridecafluorooctyltrimethoxysilane, 3000ml of water and 2000ml of ethanol are mixed and subjected to sol-gel reaction continuously at 90 ℃ to prepare a sol solution of fluorinated silane.
6) Mixing the silane sol solution with the uniformly dispersed carbon nanotube solution obtained in the step 4) according to the mass ratio of 8:2 to obtain the carbon nanotube/perfluorosilane composite sol material for the proppant.
7) The 10-20 mesh quartz sand was washed in ethanol and water, and air dried at 70 ℃ for 2.5 hours.
8) Heating the cleaned and dried quartz sand to 120 ℃ in an ethanol water solution, adding the carbon nano tube/perfluorosilane composite sol obtained in the step 6) under stirring, stirring for 1 hour, and standing for 10min to complete the reaction. Wherein the mass ratio of the carbon nano tube/perfluorosilane composite sol material to the quartz sand is 6.
9) Heating the quartz sand particles coated with the carbon nano tube/perfluorosilane prepared in the step 8) at 160 ℃ for 5 hours in vacuum, removing residual chemical substances (ethanol, water, unreacted tetraethoxysilane, tridecafluorooctyltrimethoxysilane and the like), and curing sol coating.
10 Quartz sand is filtered, cooled, crushed and sieved to obtain the proppant coated with the carbon nano tube/perfluorosilane composite material.
Example 2
Raw materials: multi-walled carbon nanotubes (Sigma-Aldrich multi-walled carbon nanotubes), potassium hydroxide (analytically pure), ethanol, ethyl orthosilicate, heptadecafluorotriethoxysilane, quartz sand, pH test paper and the like;
quartz sand: the grain size range is 10-20 meshes;
the preparation method comprises the following steps:
1) 40g of multi-walled carbon nanotubes and 1000g of potassium hydroxide were mixed in a laboratory ball mill and about 200ml of ethanol were added and ball milled for 30 hours.
2) After ball milling was complete, all reactants were washed with deionized water to neutral pH.
3) And (3) putting the neutral carbon nano tube sample into a vacuum drying oven, and drying for 24 hours at 140 ℃ to obtain the carbon nano tube with the hydroxylated surface.
4) 20g of the carbon nano tube with the hydroxylated surface is taken to be dispersed in 1000ml of ethanol in a water bath for 4 hours by ultrasonic.
5) 500g of tetraethoxysilane, 500g of heptadecafluorotriethoxysilane, 3000ml of water and 2000ml of ethanol were taken and subjected to a sol-gel reaction continuously at 90 ℃ to prepare a sol solution of fluorinated silane.
6) Mixing the silane sol solution with the uniformly dispersed carbon nanotube solution obtained in the step 4) according to the mass ratio of 8:2 to obtain the carbon nanotube/perfluorosilane composite sol material for coating the propping agent.
7) The quartz sand of 10-20 mesh was washed in ethanol and water, respectively, and air-dried at 70 ℃ for 2.5 hours.
8) In ethanol water, heating the cleaned and dried quartz sand to 120 ℃, adding the carbon nano tube/perfluorosilane composite sol obtained in the step 6) while stirring, stirring for 1 hour, and standing for 10min to complete the reaction. Wherein the mass ratio of the carbon nano tube/perfluorosilane composite sol material to the quartz sand is 6.
9) Heating the quartz sand particles coated with the carbon nano tube/perfluorosilane prepared in the step 8) at 160 ℃ for 5 hours in vacuum, removing residual chemical substances (ethanol, water, unreacted tetraethoxysilane, tridecafluorooctyltrimethoxysilane and the like), and curing sol coating.
10 Quartz sand is filtered, cooled, crushed and sieved to obtain the proppant coated with the carbon nano tube/perfluorosilane composite material.
Example 3
Raw materials: multi-walled carbon nanotubes (Sigma-Aldrich multi-walled carbon nanotubes), potassium hydroxide (analytical grade), ethanol, ethyl orthosilicate, perfluorooctyltrimethoxysilane, quartz sand, pH test paper and the like;
quartz sand: the grain size range is 10-20 meshes;
the preparation method comprises the following steps:
1) 40g of multi-walled carbon nanotubes and 1000g of potassium hydroxide were mixed in a laboratory ball mill, and about 200ml of ethanol was added thereto and ball-milled for 30 hours.
2) After ball milling was complete, all reactants were washed with deionized water to neutral pH.
3) And (3) putting the neutral carbon nano tube sample into a vacuum drying oven, and drying for 24 hours at 140 ℃ to obtain the carbon nano tube with the surface hydroxylated.
4) 20g of the carbon nano tube with the hydroxylated surface is taken to be dispersed in 1000ml of ethanol in a water bath for 4 hours by ultrasonic.
5) 500g of tetraethoxysilane, 500g of perfluorooctyltrimethoxysilane, 3000ml of water and 2000ml of ethanol are taken and subjected to sol-gel reaction continuously at 90 ℃ to prepare a sol solution of fluorinated silane.
6) Mixing the silane sol solution with the uniformly dispersed carbon nanotube solution obtained in the step 4) according to the mass ratio of 8:2 to obtain the carbon nanotube/perfluorosilane composite sol material for coating the propping agent.
7) The quartz sand of 10-20 mesh was washed in ethanol and water, respectively, and air-dried at 70 ℃ for 2.5 hours.
8) Heating the cleaned and dried quartz sand to 120 ℃ in an ethanol water solution, adding the carbon nano tube/perfluorosilane composite sol obtained in the step 6) under stirring, stirring for 1 hour, and standing for 10min to complete the reaction. Wherein the mass ratio of the carbon nano tube/perfluorosilane composite sol material to the quartz sand is 6.
9) Heating the quartz sand particles coated with the carbon nano tube/perfluorosilane prepared in the step 8) at 160 ℃ for 5 hours in vacuum, removing residual chemical substances (ethanol, water, unreacted tetraethoxysilane, tridecafluorooctyltrimethoxysilane and the like), and curing sol coating.
10 Quartz sand is filtered, cooled, crushed and sieved to obtain the proppant coated with the carbon nanotube/perfluorosilane composite material.
Example 4
Raw materials: multi-walled carbon nanotubes (Sigma-Aldrich multi-walled carbon nanotubes), potassium hydroxide (analytical grade), ethanol, ethyl orthosilicate, tridecafluorooctyltrimethoxysilane, quartz sand, pH test paper and the like;
quartz sand: the grain size range is 10-20 meshes;
the preparation method comprises the following steps:
1) 40g of multi-walled carbon nanotubes and 1000g of potassium hydroxide were mixed in a laboratory ball mill and about 200ml of ethanol were added and ball milled for 30 hours.
2) After ball milling was complete, all reactants were washed with deionized water to neutral pH.
3) And (3) putting the neutral carbon nano tube sample into a vacuum drying oven, and drying for 24 hours at 140 ℃ to obtain the carbon nano tube with the surface hydroxylated.
4) 20g of the carbon nano-tube with the surface hydroxylated is taken to be dispersed in 1000ml of ethanol in a water bath by ultrasonic for 4 hours.
5) 500g of ethyl orthosilicate, 500g of tridecafluorooctyltrimethoxysilane, 3000ml of water and 2000ml of ethanol were taken and subjected to a sol-gel reaction continuously at 80 ℃ to prepare a sol solution of fluorinated silane.
6) Mixing the silane sol solution with the uniformly dispersed carbon nano tube solution obtained in the step 4) according to the mass ratio of 8:2 to obtain the carbon nano tube/perfluorosilane composite sol material for coating the propping agent.
7) The quartz sand of 10-20 mesh was washed in ethanol and water, respectively, and air-dried at 70 ℃ for 2.5 hours.
8) In ethanol water, heating the cleaned and dried quartz sand to 120 ℃, adding the carbon nano tube/perfluorosilane composite sol obtained in the step 6) while stirring, stirring for 1 hour, and standing for 10min to complete the reaction. Wherein the mass ratio of the carbon nano tube/perfluorosilane composite sol material to the quartz sand is 6.
9) Heating the quartz sand particles coated with the carbon nano tube/perfluorosilane prepared in the step 8) at 160 ℃ for 5 hours in vacuum, removing residual chemical substances (ethanol, water, unreacted tetraethoxysilane, tridecafluorooctyltrimethoxysilane and the like), and curing sol coating.
10 Quartz sand is filtered, cooled, crushed and sieved to obtain the proppant coated with the carbon nano tube/perfluorosilane composite material.
The self-suspending proppants of examples 1-4 were mass tested according to standard SY/T5108-2014, and the results are shown in Table 1:
TABLE 1 quality test results for self-suspending proppant products from examples 1-4
Technical effects
The self-suspending proppant synthesized by the application has hydrophobic and oleophobic surface and can resist temperature up to 90 ℃.20 g of self-suspending proppant was weighed into a clean beaker, 200ml of deionized water was added, and mechanical stirring was performed with a timer. Regulating the rotation speed of the mechanical stirrer to 600-700r/min, stirring for 5min, stopping stirring, and standing. And observing the distribution state of the proppant and recording the time for the proppant/water system to be completely stable. The time during which the proppant phase surface and the liquid surface reach a parallel position and remain in a stable state is taken as the stabilization time. The same method is adopted to observe the stabilization time of the self-suspending proppant system under different sand ratios. By adopting a proppant of which the surface is not modified with the carbon nano tube composite material as a contrast experiment, the common quartz sand particles can be found to be rapidly settled after the stirring is stopped, and an obvious interface is formed. The stabilization times for different sand to liquid ratios are shown in table 2.
TABLE 2 suspension stability time of self-suspending proppants at different Sand ratios
As can be seen from Table 2, the self-suspending proppants with different sand ratios can form a self-suspending system within 4min, have better sand suspending performance, and the suspended proppants have no phenomena of agglomeration, line formation and the like in the solution and are distributed more uniformly. And all experiments can be realized at a lower rotating speed, and the requirements on equipment in field application can be effectively controlled.
20g of self-suspending proppant was weighed into a clean beaker, 200ml of deionized water was added, and mechanical stirring and timing was performed. Adjusting the rotation speed of the mechanical stirrer to 600-700r/min, stirring for 5min, stopping, and standing. The resulting mixed system was capped and sealed, placed in a constant temperature water bath (room temperature, 40 ℃, 90 ℃) and allowed to stand, and the time taken for the proppant to settle completely was observed and recorded, as shown in table 3.
TABLE 3 Settlement time of self-suspending proppants at different sand ratios
The experimental result shows that the complete settling time of the proppant particles in the self-suspending proppant solution (normal temperature, 40 ℃ and 90 ℃) is more than 1.5h, which indicates that the self-suspending proppant fracturing fluid has excellent sand suspending stability and better temperature resistance.
20g of self-suspending proppant was weighed into a clean beaker, 200ml of deionized water was added, and mechanical stirring and timing was performed. Regulating the rotation speed of the mechanical stirrer to 600-700r/min, stirring for 5min, stopping stirring, and standing. 0.1% of ammonium persulfate is added into the fracturing fluid of the self-suspending proppant as a gel breaker, gel breaking experiments are carried out under water bath conditions of different temperatures (40 ℃, 60 ℃ and 90 ℃), the apparent viscosity of the solution is measured every 10min, the gel breaking condition is observed and recorded, when the apparent viscosity measured for three times continuously does not change any more, the gel breaking is considered to be completed, and the data is recorded in table 4.
TABLE 4 evaluation results of gel breaking performance of self-suspending proppant fracturing fluids
According to the experimental results, under the temperature conditions selected by the experiment, the residue content of the gel breaking liquid of the prepared self-suspending proppant fracturing fluid is lower than 100mg/L, and the requirement that the residue content of the water-based fracturing fluid is not more than 600mg/L in 'fracturing fluid general technical conditions' of oil and gas industry standard (SY/T6376-2008) is met. The prepared self-suspending proppant fracturing fluid has low possibility of causing secondary damage to the reservoir.
It should be noted that the above-mentioned embodiments are only for explaining the present invention, and do not constitute any limitation to the present invention. The present invention has been described with reference to exemplary embodiments, but the words which have been used herein are words of description and illustration, rather than words of limitation. The invention can be modified, as prescribed, within the scope of the claims and without departing from the scope and spirit of the invention. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein, but rather extends to all other methods and applications having the same functionality.
Claims (10)
1. The method for synthesizing the carbon nano tube/perfluorosilane composite sol material is characterized by comprising the following steps of:
(1) Carrying out sol-gel reaction on a silicon source and fluoroalkyl alkoxy silane to prepare a sol solution of fluorinated silane;
(2) And mixing the fluorinated silane sol solution with the carbon nano tube with the hydroxylated surface to prepare the carbon nano tube/perfluorosilane composite sol material.
2. The synthesis method according to claim 1, wherein the preparation method of the surface hydroxylated carbon nanotube comprises: adding strong base into the carbon nano tube, treating the carbon nano tube by adopting high-energy ball milling, and washing and drying the carbon nano tube;
preferably, the strong base is an alkali metal hydroxide, preferably at least one of potassium hydroxide and sodium hydroxide; and/or the carbon nanotubes are multi-walled carbon nanotubes; and/or the weight ratio of the carbon nanotubes to the strong base is 10 to 60, 30 to 50, for example 40; and/or the ball milling time is 30-35 hours; and/or ethanol is used as a ball milling medium, and the ratio of the volume of the ethanol to the mass of the carbon nano tubes is 4-6 ml/g.
3. The synthesis method according to claim 1 or 2, wherein in step 1), the silicon source is tetraethoxysilane, and/or
The fluoroalkyl group in the fluoroalkyl alkoxy silane is a C6-C12 fluoroalkyl group with 10-20 fluorine atoms, and is preferably a C8-C12 fluoroalkyl group with 12-17 fluorine atoms; and/or the alkoxy group is a C1-C6 alkoxy group, preferably a C1-C3 alkoxy group, for example, a methoxy or ethoxy group;
preferably, the fluoroalkylalkoxysilane is heptadecafluorodecyltriethoxysilane, tridecafluorooctyltrimethoxysilane or dodecafluoroheptylpropyltrimethoxysilane; and/or
The weight ratio of the surface hydroxylated carbon nanotube to the silicon source to the fluoroalkyl alkoxy silane is 10-30 and is (wt%) 400-600, and/or the temperature of sol-gel reaction is 80-100 ℃, and/or the surface hydroxylated carbon nanotube is mixed with the sol solution of the fluorinated silane in the form of dispersion liquid, wherein the mass ratio of the dispersion liquid to the sol solution of the fluorinated silane is 1-3:6-10, and the dispersion liquid contains 10-30 g of the surface hydroxylated carbon nanotube and 700-1300 ml of ethanol.
4. A carbon nanotube/perfluorosilane composite sol material prepared according to the synthesis method of any one of claims 1 to 3.
5. The use of the carbon nanotube/perfluorosilane composite sol material according to claim 4 for the preparation of self-suspending proppant.
6. Self-suspending proppant, characterized in that it comprises quartz sand and a coating film formed of the carbon nanotube/perfluorosilane composite sol material according to claim 4.
7. A method of making the self-suspending proppant of claim 6, comprising the steps of:
1) Applying the carbon nanotube/perfluorosilane composite sol material according to claim 4 to the surface of quartz sand;
2) And (3) heating the quartz sand with the carbon nano tube/perfluorosilane composite sol material in vacuum to form a coating on the quartz sand.
8. The preparation method according to claim 7, wherein in the step 1), the carbon nanotube/perfluorosilane composite sol material is applied to the surface of quartz sand by mixing or spraying, and the mass ratio of the carbon nanotube/perfluorosilane composite sol material to the quartz sand is 1-10:100.
9. the method according to claim 8, wherein the nanotube/perfluorosilane composite sol material is applied to the surface of the quartz sand by mixing at a temperature of 100-150 ℃ and/or by spraying at a temperature of 80-90 ℃.
10. The production method according to any one of claims 7 to 9, wherein the vacuum heating in step 2) is performed at a temperature of 160 to 180 ℃ for 5 to 6 hours.
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Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101268150A (en) * | 2005-09-23 | 2008-09-17 | 川汉油田服务有限公司 | Slurry compositions and methods for making same |
| CN103626403A (en) * | 2012-08-27 | 2014-03-12 | 中国科学院兰州化学物理研究所 | Preparation method of transparent super-amphiphobic coating |
| CN104789124A (en) * | 2014-12-30 | 2015-07-22 | 中国科学院兰州化学物理研究所 | A preparing method of a stable superamphiphobic surface |
| CN105440888A (en) * | 2015-12-17 | 2016-03-30 | 中国科学院兰州化学物理研究所 | Preparation method of stable superhydrophobic hot liquid coating |
| CN105562314A (en) * | 2015-12-17 | 2016-05-11 | 上海必定化工有限公司 | Preparation method of transparent super-amphiphobic hot water and hot oil coating |
| CN105802446A (en) * | 2016-03-31 | 2016-07-27 | 武汉理工大学 | Wear-resistant and super-hydrophobic coating material and preparation method thereof |
| CN106147744A (en) * | 2016-06-30 | 2016-11-23 | 西南科技大学 | A kind of preparation method of the proppant being enclosed with super-hydrophobic polymeric membrane |
| CN106189832A (en) * | 2016-07-13 | 2016-12-07 | 华南理工大学 | Organopolysilazane/inorganic nano material super-hydrophobic coat and preparation method thereof |
| CN106800885A (en) * | 2016-12-21 | 2017-06-06 | 中国科学院兰州化学物理研究所 | A kind of large-scale preparation method of transparent hydrophobic/super-amphiphobic coating |
| CN112424313A (en) * | 2018-05-14 | 2021-02-26 | 沙特阿拉伯石油公司 | Nanocomposite coated proppants and methods of making and using the same |
| CN112680209A (en) * | 2019-10-17 | 2021-04-20 | 中国石油化工股份有限公司 | Proppant and preparation method thereof |
| CN113388293A (en) * | 2021-06-11 | 2021-09-14 | 中国科学院兰州化学物理研究所 | Preparation method of durable photo-thermal real-time self-repairing super-amphiphobic coating |
-
2021
- 2021-07-16 CN CN202110805354.3A patent/CN115612480A/en active Pending
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101268150A (en) * | 2005-09-23 | 2008-09-17 | 川汉油田服务有限公司 | Slurry compositions and methods for making same |
| CN103626403A (en) * | 2012-08-27 | 2014-03-12 | 中国科学院兰州化学物理研究所 | Preparation method of transparent super-amphiphobic coating |
| CN104789124A (en) * | 2014-12-30 | 2015-07-22 | 中国科学院兰州化学物理研究所 | A preparing method of a stable superamphiphobic surface |
| CN105440888A (en) * | 2015-12-17 | 2016-03-30 | 中国科学院兰州化学物理研究所 | Preparation method of stable superhydrophobic hot liquid coating |
| CN105562314A (en) * | 2015-12-17 | 2016-05-11 | 上海必定化工有限公司 | Preparation method of transparent super-amphiphobic hot water and hot oil coating |
| CN105802446A (en) * | 2016-03-31 | 2016-07-27 | 武汉理工大学 | Wear-resistant and super-hydrophobic coating material and preparation method thereof |
| CN106147744A (en) * | 2016-06-30 | 2016-11-23 | 西南科技大学 | A kind of preparation method of the proppant being enclosed with super-hydrophobic polymeric membrane |
| CN106189832A (en) * | 2016-07-13 | 2016-12-07 | 华南理工大学 | Organopolysilazane/inorganic nano material super-hydrophobic coat and preparation method thereof |
| CN106800885A (en) * | 2016-12-21 | 2017-06-06 | 中国科学院兰州化学物理研究所 | A kind of large-scale preparation method of transparent hydrophobic/super-amphiphobic coating |
| CN112424313A (en) * | 2018-05-14 | 2021-02-26 | 沙特阿拉伯石油公司 | Nanocomposite coated proppants and methods of making and using the same |
| CN112680209A (en) * | 2019-10-17 | 2021-04-20 | 中国石油化工股份有限公司 | Proppant and preparation method thereof |
| CN113388293A (en) * | 2021-06-11 | 2021-09-14 | 中国科学院兰州化学物理研究所 | Preparation method of durable photo-thermal real-time self-repairing super-amphiphobic coating |
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