阅读说明：本技术 一种碳纳米管/纤维改性的自加热多孔疏水/亲油陶瓷及其制备方法 (Carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic and preparation method thereof ) 是由 张海军 黄仲 张俊 张少伟 于 2020-11-20 设计创作，主要内容包括：本发明提供一种碳纳米管/纤维改性的自加热多孔疏水/亲油陶瓷及其制备方法,所述自加热多孔疏水/亲油陶瓷由多孔陶瓷改性得到,在多孔陶瓷内外表面均包覆一层疏水/亲油的碳纳米管/纤维层。本发明提供的碳纳米管/纤维改性的自加热多孔疏水/亲油陶瓷具有陶瓷材料优异的机械强度和化学稳定性,孔隙率高,透气度高,导热性能好,而且具有良好的疏水亲油性,可在外加电场的作用下进行自加热,所产生的热量能快速扩散到周围的高粘度原油,增大其流动性,从而实现高粘度原油的高效分离。(The invention provides a carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic and a preparation method thereof. The carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic provided by the invention has the advantages of excellent mechanical strength and chemical stability of ceramic materials, high porosity, high air permeability, good heat conductivity, good hydrophobicity and oleophylic property, and can be self-heated under the action of an external electric field, and the generated heat can be rapidly diffused to surrounding high-viscosity crude oil to increase the fluidity of the crude oil, so that the high-efficiency separation of the high-viscosity crude oil is realized.)

1. A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is characterized in that the self-heating porous hydrophobic/oleophylic ceramic is obtained by modifying porous ceramic, and a layer of hydrophobic/oleophylic carbon nanotube/fiber layer is coated on the inner surface and the outer surface of the porous ceramic;

the preparation method comprises the following steps: mixing sodium carboxymethylcellulose, a transition metal precursor and deionized water to prepare a catalyst precursor solution; immersing the porous ceramic in the obtained catalyst precursor solution, fully vacuum impregnating, drying, covering the porous ceramic subjected to impregnation and drying with waste plastic powder, and calcining to obtain the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic.

2. The carbon nanotube/fiber modified self-heating porous hydrophobic/oleophilic ceramic as claimed in claim 1, wherein the transition metal precursor is one or more of ferric nitrate, cobalt nitrate, nickel nitrate, ferric chloride, cobalt chloride, nickel chloride, all of which are industrially pure or analytically pure, and the particle size is less than or equal to 100 μm;

the mass ratio of the sodium carboxymethylcellulose to the transition metal precursor to the deionized water is 1: 100: 300 to 3000.

3. The carbon nanotube/fiber modified self-heating porous hydrophobic/oleophilic ceramic according to claim 1, wherein the porous ceramic is one of porous sepiolite ceramic, porous diatomaceous earth ceramic, porous mullite ceramic, porous magnesia alumina spinel ceramic, porous calcium titanate ceramic, porous alumina ceramic, porous zirconia ceramic, porous titanium carbide ceramic, porous silicon carbide ceramic and porous silicon nitride ceramic, and has a porosity of 50 to 90%, a compressive strength of 0.5 to 25.0MPa, and a density of 0.5 to 1.5g/cm³。

4. The carbon nanotube/fiber modified, self-heating, porous, hydrophobic/oleophilic ceramic of claim 1, wherein the mass ratio of the porous ceramic to the catalyst precursor solution is 1: 10 to 12.

5. The carbon nanotube/fiber modified self-heating porous hydrophobic/oleophilic ceramic of claim 1, wherein the vacuum impregnation process conditions are: dipping for 0.5-2 hours under the vacuum degree of 1-100 Pa;

the drying conditions are as follows: heating for 10-14 hours at 60-80 ℃.

6. The carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic according to claim 1, wherein the waste plastic powder is one or more of polyethylene, polypropylene and polyvinyl chloride, and the particle size is less than or equal to 10 μm;

the mass ratio of the porous ceramic to the waste plastic powder is 1: 5 to 10.

7. The carbon nanotube/fiber modified self-heating porous hydrophobic/oleophilic ceramic according to claim 1, wherein the calcination treatment process conditions are: at H₂And in the mixed atmosphere of Ar and the mixture, heating to 500-900 ℃ at the heating rate of 2-10 ℃/min, and preserving heat for 1-5 hours.

8. The carbon nanotube/fiber modified self-heating porous hydrophobic/oleophilic ceramic of claim 1, wherein the H is₂And H in Ar mixed atmosphere₂The volume percentage content is 5 percent.

9. A method for preparing the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic according to any one of claims 1 to 8, which is characterized by comprising the following steps: mixing sodium carboxymethylcellulose, a transition metal precursor and deionized water to prepare a catalyst precursor solution; immersing the porous ceramic in the obtained catalyst precursor solution, fully vacuum impregnating, drying, covering the porous ceramic subjected to impregnation and drying with waste plastic powder, and calcining to obtain the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic.

10. Use of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophilic ceramic of any one of claims 1-8 for oil-water separation.

Technical Field

The invention belongs to the technical field of contact separation of a solid phase which can be preferentially wetted, and particularly relates to a carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic and a preparation method thereof.

Background

With the rapid development of offshore oil exploitation and industry, offshore oil leakage accidents frequently occur, and oil drainage accidents cause large-area sea areas to be covered and polluted by crude oil, so that not only is the ecological environment irreversibly damaged, but also the non-renewable energy resources are greatly wasted. How to simply and efficiently collect and treat crude oil leakage pollution has become a world-level challenge, and has attracted extensive attention of researchers. The traditional methods for treating oil pollution mainly comprise a fence method, a combustion method, a chemical dispersion method, a biodegradation method and the like, but the methods have high cost and low efficiency and sometimes even cause secondary pollution. In contrast, the recovery of crude oil by means of a physical separation method by means of hydrophobic/oleophilic materials has little influence on the environment and is the main consideration method for treating oil leakage at present. However, 40% of crude oil in the world has a viscosity of up to 10 at normal temperature³～10⁵mPa · s, the recovery of high viscosity crude oil, often requires thermal pretreatment of the crude oil to reduce its viscosity and increase its fluidity. Many current hydrophobic/oleophilic materials such as films, aerogels, modified foams and sponges, for low viscosity oils: (<500mPa · s), but these materials have poor separation ability for high viscosity crude oil, and all have the disadvantages of low mechanical strength, poor chemical stability, no high temperature resistance, etc., to varying degrees, so it is difficult to reduce the viscosity of crude oil by self-heating.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides the carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic which has low cost and simple synthesis process and is suitable for industrial production and the preparation method thereof; the carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic has high porosity, high strength, high air permeability and good heat conductivity, can be self-heated under the action of an external voltage, and has high oil-water separation efficiency when used for crude oil.

In order to achieve the purpose, the invention adopts the technical scheme that:

providing a carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic, wherein the self-heating porous hydrophobic/oleophylic ceramic is obtained by modifying porous ceramic, and a hydrophobic/oleophylic carbon nanotube/fiber layer is coated on the inner surface and the outer surface of the porous ceramic;

the preparation method comprises the following steps: mixing sodium carboxymethylcellulose, a transition metal precursor and deionized water to prepare a catalyst precursor solution; immersing the porous ceramic in the obtained catalyst precursor solution, fully vacuum impregnating, drying, covering the porous ceramic subjected to impregnation and drying with waste plastic powder, and calcining to obtain the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic.

According to the scheme, the compressive strength of the self-heating porous hydrophobic/oleophylic ceramic is 1.2-16.5 MPa; the contact angle between the surface and water is 139-147 degrees, and the contact angle with vacuum pump oil is 1-6 degrees.

According to the scheme, the transition metal precursor is one or more of ferric nitrate, cobalt nitrate, nickel nitrate, ferric chloride, cobalt chloride and nickel chloride, and is of industrial purity or analytical purity, and the particle size is less than or equal to 100 mu m. The invention takes the transition metal precursor as the catalyst precursor, can synthesize the carbon nano tube/fiber at lower temperature, does not need high-temperature treatment, and reduces the energy consumption.

According to the scheme, the mass ratio of the sodium carboxymethylcellulose to the transition metal precursor to the deionized water is 1: 100: 300 to 3000.

According to the scheme, the porous ceramic is one of porous sepiolite ceramic, porous diatomite ceramic, porous mullite ceramic, porous magnesia-alumina spinel ceramic, porous calcium titanate ceramic, porous alumina ceramic, porous zirconia ceramic, porous titanium carbide ceramic, porous silicon carbide ceramic and porous silicon nitride ceramic, the porosity is 50-90%, the compressive strength is 0.5-25.0 MPa, and the density is 0.5-1.5 g/cm³。

According to the scheme, the mass ratio of the porous ceramic to the catalyst precursor solution is 1: 10 to 12.

According to the scheme, the vacuum impregnation process conditions are as follows: immersing the substrate in a vacuum of 1-100 Pa for 0.5-2 hours.

According to the scheme, the drying conditions are as follows: heating for 10-14 hours at 60-80 ℃.

According to the scheme, the waste plastic powder is one or more of polyethylene, polypropylene and polyvinyl chloride, and the particle size is less than or equal to 10 microns. The invention synthesizes the carbon nano tube/fiber by using the waste plastic powder as the carbon source, has wide source and low price, and the recycling of the waste plastic is beneficial to solving the environmental problem of white pollution, thereby having good social benefit and ecological benefit.

According to the scheme, the mass ratio of the porous ceramic to the waste plastic powder is 1: 5 to 10.

According to the scheme, the calcination treatment process conditions are as follows: at H₂And in the mixed atmosphere of Ar and the mixture, heating to 500-900 ℃ at the heating rate of 2-10 ℃/min, and preserving heat for 1-5 hours. In the calcining process, the metal precursor is reduced into single metal nano particles under the action of hydrogen, and the single metal nano particles are used as a catalyst to catalyze and crack waste plastics, so that the carbon nano tubes/carbon fibers are synthesized on the surface of the porous ceramic.

According to the scheme, the H₂And H in Ar mixed atmosphere₂The volume percentage content is 5 percent.

The invention also provides a preparation method of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic, which comprises the following specific steps: mixing sodium carboxymethylcellulose, a transition metal precursor and deionized water to prepare a catalyst precursor solution; immersing the porous ceramic in the obtained catalyst precursor solution, fully vacuum impregnating, drying, covering the porous ceramic subjected to impregnation and drying with waste plastic powder, and calcining to obtain the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic.

And the application of the carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic in oil-water separation. The ceramic was mounted in the apparatus described in CN202020613069.2 and the oil/water mixture was separated under an applied voltage.

The application takes porous ceramic as a substrate, and catalyst precursor solution is impregnated into the porous ceramicAfter the solution is added with H₂The transition metal precursor uniformly dispersed in the porous ceramic pores is firstly reduced into transition metal nano particles by hydrogen in the high-temperature calcination treatment process, and then the transition metal nano particles are used as a catalyst to catalyze and crack waste plastic powder to generate carbon nano tubes/fibers on the surface of the porous ceramic in situ, wherein the surface of the internal pores of the porous ceramic integrally covers a layer of carbon nano tubes/fibers. Due to the hydrophobicity and the electrical conductivity of the carbon nano tube/fiber, the self-heating porous hydrophobic/oleophylic ceramic modified by the carbon nano tube/fiber shows the hydrophobic/oleophylic characteristic, and meanwhile, the carbon nano tube/fiber on the surface can generate Joule heat under the action of an external voltage, so that the viscosity of crude oil is reduced, the simultaneous heating and oil-water separation is realized, and the separation efficiency of the crude oil is improved.

The invention has the beneficial effects that:

1. the carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic provided by the invention has the advantages of excellent mechanical strength and chemical stability of ceramic materials, high porosity, high air permeability, good heat conductivity, good hydrophobicity and oleophylic property, and can be self-heated under the action of an external electric field, and the generated heat can be rapidly diffused to surrounding high-viscosity crude oil to increase the fluidity of the crude oil, so that the high-efficiency separation of the high-viscosity crude oil is realized.

2. The invention takes porous ceramic which is a commonly used material in industry as a raw material, has low production cost and simple process flow, is suitable for industrialization and has high economic value.

Drawings

FIG. 1 is a scanning electron micrograph of a porous ceramic used in example 1 of the present invention;

FIG. 2 is a scanning electron microscope image of the carbon nanotube/fiber distribution on the surface of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophilic ceramic prepared in example 1;

FIG. 3 is a scanning electron microscope image of the carbon nanotube/fiber distribution of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophilic ceramic surface prepared in example 1;

fig. 4 is a graph of self-heating temperature over time under applied voltage for the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophilic ceramic prepared in example 1.

Detailed Description

The invention is further described with reference to specific embodiments, without limiting its scope.

To avoid repetition, the following steps in this embodiment are first performed: the transition metal precursor is one or more of ferric nitrate, cobalt nitrate, nickel nitrate, ferric chloride, cobalt chloride and nickel chloride, and is industrially pure or analytically pure, and the particle size is less than or equal to 100 mu m.

The porous ceramic is one of porous sepiolite ceramic, porous diatomite ceramic, porous mullite ceramic, porous magnesia alumina spinel ceramic, porous calcium titanate ceramic, porous alumina ceramic, porous zirconia ceramic, porous titanium carbide ceramic, porous silicon carbide ceramic and porous silicon nitride ceramic, the porosity is 50-90%, the compressive strength is 0.5-25.0 MPa, and the density is 0.5-1.5 g/cm³。

The waste plastic powder is one or more of polyethylene, polypropylene and polyvinyl chloride, and the particle size is less than or equal to 10 mu m.

The detailed description is omitted in the embodiments.

Example 1

A carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by the following steps:

according to the weight percentage of sodium carboxymethylcellulose: transition metal precursor (ferric nitrate): the mass ratio of the deionized water is 1: 100: 1000, preparing a catalyst precursor solution;

1 part by mass of a porous ceramic (porous sepiolite ceramic, 40X 200 mm)³Compressive strength 1.7MPa) was immersed in 10 parts by mass of the catalyst precursor solution prepared above, vacuum-impregnated at a vacuum degree of 100Pa for 2 hours, and then dried at 80 ℃ for 10 hours, and the resultant porous ceramic after dip-drying treatment was placed in a graphite mold and completely covered with 5 parts by mass of waste plastic powder (polyethylene), and the mold was placed in an atmosphere furnace in H₂Under the atmosphere of/Ar (H)₂5 percent of volume percent), heating to 500 ℃ at the heating rate of 5 ℃/min, and keeping the temperature for 5 hoursAnd cooling to room temperature along with the furnace to obtain the carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic.

The scanning electron microscope image of the porous ceramic used in this example is shown in fig. 1, and the scanning electron microscope image and the further enlarged image of the self-heating porous hydrophobic/oleophilic ceramic obtained after modification are shown in fig. 2 and fig. 3, and it can be seen that a layer of carbon nanotube/fiber layer is distributed on the surface of the ceramic after modification.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 1.8 MPa; the contact angle of the surface and water is 145 degrees, and the contact angle of the surface and vacuum pump oil is 2 degrees. A parallel voltage (24V) is applied to the self-heating porous hydrophobic/oleophylic ceramic modified by the carbon nano tube/fiber, the ceramic is directly electrified and heated, the heating temperature of the ceramic is tested to change along with time, and a test chart is shown in figure 4, and it can be seen that the ceramic can be self-heated to 58 ℃ within 40 seconds after being electrified.

The carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is processed into 20X 150mm³The size of (2) is placed in an oil-water separation device disclosed in application No. 202020613069.2, 24V voltage is applied on the self-heating porous hydrophobic/oleophilic ceramic, the generated heat can be diffused to crude oil to reduce the viscosity of the crude oil, the device is connected with a self-priming pump (rated voltage of 12V, opening flow rate of 2.6L/min, motor rotating speed of 2800r/min, suction lift of 1.5m), the device is placed at an interface of a mixture of crude oil and water (the volume ratio of crude oil to water is 1: 2), and the separation rate and the separation efficiency of the carbon nano tube/fiber modified self-heating porous hydrophobic/oleophilic ceramic to the crude oil/water mixture are measured.

The carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic of this example was tested to separate the crude oil/water mixture at a rate of 120Kg s per unit surface area of time^-1·m^-2(the separation rate is 12Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 96%.

Example 2

A carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by the following steps:

according to the weight percentage of sodium carboxymethylcellulose: transition metal precursor (ferric nitrate): the mass ratio of the deionized water is 1: 100: 2100 preparing a catalyst precursor solution;

1 part by mass of a porous ceramic (porous sepiolite ceramic, 40X 200 mm)³Compressive strength 1.7MPa) was immersed in 11 parts by mass of the catalyst precursor solution prepared above, vacuum-impregnated at 50Pa for 1 hour, and then dried at 70 ℃ for 12 hours, and the resultant porous ceramic after dip-drying treatment was placed in a graphite mold and completely covered with 10 parts by mass of waste plastic powder (polyethylene), and the mold was placed in an atmosphere furnace in H₂Under the atmosphere of/Ar (H)₂5 percent of volume percent), heating to 700 ℃ at the heating rate of 5 ℃/min, preserving heat for 3 hours, and cooling to room temperature along with the furnace to obtain the carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 1.7 MPa; the contact angle between the surface and water is 143 degrees, and the contact angle with vacuum pump oil is 4 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture in the same manner as in example 1, and the separation rate of the crude oil/water mixture per unit surface area per unit time was found to be 102Kg · s^-1·m^-2(the separation rate is 11Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 95%.

Example 3

A carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by the following steps:

according to the weight percentage of sodium carboxymethylcellulose: transition metal precursor (ferric nitrate): the mass ratio of the deionized water is 1: 100: 300 preparing a catalyst precursor solution;

1 part by mass of a porous ceramic (porous sepiolite ceramic, 40X 200 mm)³Compressive strength 1.7MPa) was immersed in 12 parts by mass of the catalyst precursor solution prepared above, vacuum-immersed at 1Pa for 0.5 hour, and then dried at 60 ℃ for 14 hours, followed by subjecting the resultant impregnated and dried porous ceramic to impregnation drying treatmentThe porcelain was placed in a graphite mold, and the porous ceramics were completely covered with 10 parts by mass of waste plastic powder (polyethylene), and the mold was placed in an atmosphere furnace in H₂Under the atmosphere of/Ar (H)₂5 percent of volume percent), heating to 900 ℃ at the heating rate of 10 ℃/min, preserving the heat for 1 hour, and cooling to room temperature along with the furnace to obtain the carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 2.0 MPa; the contact angle between the surface and water is 146 degrees, and the contact angle with vacuum pump oil is 2 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate per unit time and unit surface area of the crude oil/water mixture was found to be 112 Kg.s^-1·m^-2(the separation rate was 14Kg · s without energization^-1·m^-2) The separation efficiency was 95%.

Example 4

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared in the same manner as in example 3 except that the transition metal precursor used is cobalt nitrate.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 1.5 MPa; the contact angle between the surface and water is 142 degrees, and the contact angle with vacuum pump oil is 5 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate of the crude oil/water mixture per unit surface area per unit time was measured to be 96Kg · s^-1·m^-2(the separation rate is 15Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 93%.

Example 5

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared in the same manner as in example 3 except that a transition metal precursor used is nickel nitrate.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 1.8 MPa; surface ofThe contact angle with water is 146 degrees, and the contact angle with vacuum pump oil is 3 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate per unit time and unit surface area of the crude oil/water mixture was measured to be 110Kg · s^-1·m^-2(the separation rate is 10Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 94%.

Example 6

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared in the same manner as in example 3 except that the transition metal precursor used is ferric chloride.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 2.0 MPa; the contact angle between the surface and water is 143 degrees, and the contact angle with vacuum pump oil is 1 degree; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate per unit time and unit surface area of the crude oil/water mixture was found to be 132Kg · s^-1·m^-2(the separation rate is 16Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 97%.

Example 7

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared in the same manner as in example 3 except that the transition metal precursor used is cobalt chloride.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 1.8 MPa; the contact angle between the surface and water is 140 degrees, and the contact angle with vacuum pump oil is 5 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate of the crude oil/water mixture per unit surface area per unit time was measured to be 96Kg · s^-1·m^-2(the separation rate is 8Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 96%.

Example 8

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared in the same manner as in example 3 except that the transition metal precursor is nickel chloride.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 1.9 MPa; the contact angle between the surface and water is 143 degrees, and the contact angle with vacuum pump oil is 6 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture in the same manner as in example 1, and the separation rate per unit time and unit surface area of the crude oil/water mixture was found to be 86 Kg.s^-1·m^-2(the separation rate is 12Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 92%.

Example 9

A carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by the following steps:

according to the weight percentage of sodium carboxymethylcellulose: transition metal precursor (cobalt nitrate): the mass ratio of the deionized water is 1: 100: 2000 preparing a catalyst precursor solution;

1 part by mass of a porous ceramic (porous diatomaceous earth ceramic, 40X 200 mm)³Compressive strength 0.9MPa) was immersed in 12 parts by mass of the catalyst precursor solution prepared above, vacuum-impregnated at 50Pa for 1 hour, and then dried at 80 ℃ for 12 hours, and the resultant porous ceramic after dip-drying treatment was placed in a graphite mold and completely covered with 10 parts by mass of waste plastic powder (polyethylene), and the mold was placed in an atmosphere furnace in H₂Under the atmosphere of/Ar (H)₂5 percent of volume percent), heating to 700 ℃ at the heating rate of 5 ℃/min, preserving the heat for 2 hours, and cooling to room temperature along with the furnace to obtain the carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 1.2 MPa; the contact angle between the surface and water is 145 degrees, and the contact angle with vacuum pump oil is 3 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture in the same manner as in example 1, and the separation rate per unit time and unit surface area of the crude oil/water mixture was found to be 82Kgs^-1·m^-2(the separation rate is 15Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 96%.

Example 10

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by preparing porous mullite ceramic (40 × 40 × 200 mm)³Compressive strength 13.9MPa), the same as in example 9.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 13.8 MPa; the contact angle between the surface and water is 142 degrees, and the contact angle with vacuum pump oil is 4 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate of the crude oil/water mixture per unit surface area per unit time was measured to be 50Kg · s^-1·m^-2(the separation rate is 25Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 95%.

Example 11

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by preparing porous magnesia-alumina spinel ceramic (40 × 40 × 200 mm)³Compressive strength 10.9MPa), the same as in example 9.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 10.5 MPa; the contact angle between the surface and water is 141 degrees, and the contact angle with vacuum pump oil is 6 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate of the crude oil/water mixture per unit surface area per unit time was measured to be 45Kg · s^-1·m^-2(the separation rate is 21Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 96%.

Example 12

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by removing porous ceramic from porous calcium titanate ceramic (40 × 40 × 200 mm)³Compressive strength 6.9MPa), othersThe same as in example 9.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 7.1 MPa; the contact angle between the surface and water is 141 degrees, and the contact angle with vacuum pump oil is 6 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate of the crude oil/water mixture per unit surface area per unit time was measured to be 45Kg · s^-1·m^-2(the separation rate is 11Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 96%.

Example 13

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by preparing porous alumina ceramic (40 × 40 × 200 mm)³Compressive strength 10.9MPa), the same as in example 9.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 10.5 MPa; the contact angle between the surface and water is 141 degrees, and the contact angle with vacuum pump oil is 6 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate of the crude oil/water mixture per unit surface area per unit time was measured to be 45Kg · s^-1·m^-2(the separation rate is 20Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 96%.

Example 14

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by removing porous ceramic from porous zirconia ceramic (40 × 40 × 200 mm)³Compressive strength 16.0MPa), the same as in example 9.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 16.5 MPa; the contact angle between the surface and water is 139 degrees, and the contact angle with vacuum pump oil is 6 degrees; the ceramics were tested for separation rate and separation efficiency of crude oil/water mixture by the same method as in example 1, and the separation rate of crude oil/water mixture per unit surface area per unit time was found to be 35Kg·s^-1·m^-2(the separation rate is 10Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 94%.

Example 15

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by the method except that the porous ceramic is porous titanium carbide ceramic (40 × 40 × 200 mm)³Compressive strength 15.9MPa), the same as in example 9.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 15.5 MPa; the contact angle between the surface and water is 141 degrees, and the contact angle with vacuum pump oil is 6 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate of the crude oil/water mixture per unit surface area per unit time was measured to be 45Kg · s^-1·m^-2(the separation rate was 13Kg · s without energization^-1·m^-2) The separation efficiency was 96%.

Example 16

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by preparing porous silicon carbide ceramic (40 × 40 × 200 mm)³Compressive strength 5.3MPa), the same as in example 9.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 5.5 MPa; the contact angle between the surface and water is 140 degrees, and the contact angle with vacuum pump oil is 4 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture in the same manner as in example 1, and the separation rate of the crude oil/water mixture per unit surface area per unit time was found to be 63 Kg.s^-1·m^-2(the separation rate is 29Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 95%.

Example 17

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by the method except that the porous ceramic is porous silicon nitride ceramic (40 × 40 × 200 mm)³Compressive strength of 12.9MPa), others are the same as those of the aboveExample 9.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 12.3 MPa; the contact angle between the surface and water is 146 degrees, and the contact angle with vacuum pump oil is 3 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture in the same manner as in example 1, and the separation rate per unit time and unit surface area of the crude oil/water mixture was found to be 86 Kg.s^-1·m^-2(the separation rate is 15Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 96%.

Example 18

A carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by the following steps:

according to the weight percentage of sodium carboxymethylcellulose: transition metal precursor (nickel nitrate): the mass ratio of the deionized water is 1: 100: 2000 preparing a catalyst precursor solution;

1 part by mass of a porous ceramic (porous sepiolite ceramic, 40X 200 mm)³Compressive strength 1.9MPa) was immersed in 12 parts by mass of the catalyst precursor solution prepared above, vacuum-impregnated at 50Pa for 2 hours, and then dried at 80 ℃ for 12 hours, and the resultant porous ceramic after dip-drying treatment was placed in a graphite mold and completely covered with 10 parts by mass of waste plastic powder (polypropylene), and the mold was placed in an atmosphere furnace in H₂Under the atmosphere of/Ar (H)₂5 percent of volume percent), heating to 600 ℃ at the heating rate of 5 ℃/min, preserving the heat for 2 hours, and cooling to room temperature along with the furnace to obtain the carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 1.9 MPa; the contact angle between the surface and water is 147 degrees, and the contact angle with vacuum pump oil is 2 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate per unit time and unit surface area of the crude oil/water mixture was found to be 121 Kg.s^-1·m^-2(the separation rate is 23Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 96%.

Example 19

A carbon nano tube/fiber modified self-heating porous hydrophobic/oleophylic ceramic, which is prepared by the method same as that of example 18 except that the waste plastic powder is polyvinyl chloride.

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 1.8 MPa; the contact angle between the surface and water is 146 degrees, and the contact angle with vacuum pump oil is 2 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture in the same manner as in example 1, and the separation rate per unit surface area of the crude oil/water mixture per unit time was measured to be 117Kg · s^-1·m^-2(the separation rate is 15Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 95%.

Example 20

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by the same method as in example 18 except that waste plastic powder is mixed powder of polyethylene and polypropylene (mass ratio is 1: 1).

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 2.0 MPa; the contact angle between the surface and water is 143 degrees, and the contact angle with vacuum pump oil is 3 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture in the same manner as in example 1, and the separation rate per unit time and unit surface area of the crude oil/water mixture was found to be 114 Kg.s^-1·m^-2(the separation rate was 17Kg · s without energization^-1·m^-2) The separation efficiency was 96%.

Example 21

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared by the same method as in example 18 except that waste plastic powder is mixed powder of polyethylene and polyvinyl chloride (mass ratio is 1: 1).

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 2.0MPa; the contact angle between the surface and water is 142 degrees, and the contact angle with vacuum pump oil is 4 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate per unit time and unit surface area of the crude oil/water mixture was measured to be 115 Kg.s^-1·m^-2(the separation rate is 22Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 95%.

Example 22

A carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic is prepared in the same manner as in example 18 except that waste plastic powder is mixed powder of polypropylene and polyvinyl chloride (mass ratio is 1: 1).

The compressive strength of the carbon nanotube/fiber modified self-heating porous hydrophobic/oleophylic ceramic prepared by the embodiment is 2.0 MPa; the contact angle between the surface and water is 146 degrees, and the contact angle with vacuum pump oil is 2 degrees; the ceramics were tested for the separation rate and the separation efficiency of the crude oil/water mixture by the same methods as in example 1, and the separation rate per unit time and unit surface area of the crude oil/water mixture was found to be 116Kg · s^-1·m^-2(the separation rate is 19Kg · s under the condition of no electricity^-1·m^-2) The separation efficiency was 95%.