Titanium dioxide-based porous ceramic composite material with photothermal performance and preparation method thereof

Abstract

The present application relates to the technical field of inorganic composite materials, and particularly relates to a titanium dioxide-based porous ceramic composite material with photothermal performance and a preparation method thereof. The preparation method of the titanium dioxide-based porous ceramic composite material with photothermal performance comprises the following steps: 1) preparing materials: mixing titanium dioxide, graphite powder, steel slag, starch and a binder, pressing and drying to obtain a mixture; wherein the mass ratio of the titanium dioxide, the graphite powder, the steel slag, the starch and the binder is 1:0.5:2:0.25-0.75:1; 2) reduction roasting: reduction roasting the mixture of step 1) to obtain the titanium dioxide-based porous ceramic composite material with photothermal performance. The titanium dioxide-based porous ceramic composite material has excellent photothermal performance, and makes full use of titanium resources and metallurgical solid waste, and realizes high-value application of titanium resources.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of inorganic composite materials, in particular to a titanium dioxide-based porous ceramic composite material with photothermal performance and a preparation method thereof. BACKGROUND

[0002] The photothermal conversion technology is an effective method for directly or indirectly capturing solar energy. In particular, the photothermal conversion induced water evaporation is a significant solar energy utilization approach. The new concept of "solar heating air-water interface" becomes one of the efficient means for solving the problem of obtaining clean fresh water from sewage and seawater. The concept of "solar heating air-water interface" focuses on the air-water interface in the water evaporation process, that is, the evaporation process can be abstracted as a process in which a very thin layer of water molecules in the air-water interface changes from a high-energy state to a vapor phase, thereby effectively reducing the heat energy loss. Based on this concept and theory, a structure and route for realizing the conversion of solar energy-heat-water vapor-pure water by using sunlight are reasonably designed, and finally clean fresh water is extracted from brackish water or wastewater. The core of this process is a new high-efficiency photothermal conversion material.

[0003] At present, the materials for realizing the photothermal conversion technology include carbon-based photothermal materials, noble metal photothermal materials, transition metal composites, etc. Although the carbon-based photothermal materials have shown good application prospects in the photothermal field, their preparation cost is high, and the secondary pollution in the preparation process is serious, which limits their large-scale application in the photothermal field. The noble metal photothermal materials will encounter a bottleneck in large-scale application due to their high raw material cost, poor scalability, complex manufacturing method, and instability and toxicity of these photothermal materials. The transition metal composites, especially black TiO2, have great potential in large-scale photothermal application. For example, Ye et al. (Adv Energy Mater, 2016: 1601811.) prepared black TiO2 nanoparticles by magnesium thermal reduction to form a self-floating photothermal film, and the solar photothermal conversion efficiency of the photothermal film under simulated sunlight reached 50%. Zhu et al. (ACS Appl Mater Inter, 2016, 8(46): 31716.) obtained black TiO2 nanocages by aluminum thermal reduction of TiO2 nanocrystals through a low-temperature molten salt method, and assembled them into a PVDF film to form a self-floating porous photothermal film. The photothermal seawater evaporation efficiency of the film under simulated sunlight reached 70.9%. Zheng et al. (Surf Interfaces, 2021, 22: 100901) synthesized black TiO2 by using commercial TiO2 as raw material through a deflagration method. The evaporation rate and photothermal conversion efficiency of the material under simulated sunlight reached 1.624 kgm -2 h -1The current synthesis process of black TiO2 is complex, the preparation cost is high, and the durability is not good because the black TiO2 is applied in the form of a thin film.

[0004] Therefore, it is of great significance to provide a new titanium dioxide-based porous ceramic composite material with photothermal properties. SUMMARY

[0005] In order to overcome the above technical defects, the application provides a titanium dioxide-based porous ceramic composite material with photothermal properties and a preparation method thereof.

[0006] The first object of the application is to provide a preparation method of a titanium dioxide-based porous ceramic composite material with photothermal properties, comprising the following steps:

[0007] 1) Preparation of raw materials: the titanium dioxide, graphite powder, steel slag, starch and adhesive are uniformly mixed, pressed into a sheet and dried to obtain a mixture; wherein the mass ratio of titanium dioxide, graphite powder, steel slag, starch and adhesive is 1:0.5:2:0.25-0.75:1;

[0008] 2) Reduction roasting: the mixture of step 1) is subjected to reduction roasting to obtain a titanium dioxide-based porous ceramic composite material with photothermal properties.

[0009] In one specific embodiment of the application, in step 1), the adhesive is polyvinyl alcohol; preferably, the adhesive is a polyvinyl alcohol solution with a mass percentage of 5-7wt%.

[0010] In one specific embodiment of the application, in step 1), the starch is analytical pure starch; the graphite powder is analytical pure graphite powder; and the chemical composition and mass percentage of the steel slag are as follows:

[0011] MgO 7.08wt%, Al2O3 5.29wt%, SiO2 13.60wt%, P2O5 1.35wt%, CaO 42.10wt%, Fe2O3 26.70wt%, TiO2 0.91wt%, MnO 0.92wt%.

[0012] In one specific embodiment of the application, in step 1), the crystal structure of the titanium dioxide is anatase type.

[0013] In one specific embodiment of the application, the content of the anatase type crystal structure in the titanium dioxide is greater than or equal to 98.5%.

[0014] In one specific embodiment of the application, in step 1), the sheet pressing is performed by using a powder sheet press.

[0015] In one specific embodiment of the present application, the pressure of the powder tablet press is 5-10 MPa.

[0016] In one specific embodiment of the present application, in step 1), the drying temperature is 120-150℃, and the time is 2-2.5h.

[0017] In one specific embodiment of the present application, in step 1), the temperature of the reduction roasting is 800℃, and the time is 2h.

[0018] In one specific embodiment of the present application, in step 1), the reduction roasting is performed in a crucible, and the mixed material is filled with a graphite layer on the upper and lower sides of the crucible.

[0019] In one specific embodiment of the present application, the thickness of the graphite layer is 1-2cm.

[0020] In one specific embodiment of the present application, the crucible is a graphite crucible.

[0021] A second object of the present application is to provide a titanium dioxide porous ceramic composite material with photothermal properties, which is prepared by the above-mentioned method for preparing a titanium dioxide porous ceramic composite material with photothermal properties.

[0022] The present application has the following beneficial effects:

[0023] 1. The preparation method of the present application can prepare a titanium dioxide-based porous ceramic composite material product with photoelectric properties, which has great potential in large-scale photothermal applications, and the preparation method simplifies the production process of the product with photothermal properties, saves costs, absorbs a large amount of metallurgical solid waste steel slag, and improves production efficiency, economic benefits and social benefits.

[0024] 2. The titanium dioxide-based porous ceramic composite material of the present application has excellent photothermal properties, fully utilizes titanium resources, and realizes high-value application of titanium resources. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 The flow chart of the preparation method of the titanium dioxide-based porous ceramic composite material with photothermal properties of the present application is shown in the figure.

[0026] Figure 2 The XRD pattern of the titanium dioxide-based porous ceramic composite material with photothermal properties of the present application is shown in the figure.

[0027] Figure 3 The ultraviolet-visible absorption spectrum of the titanium dioxide-based porous ceramic composite material with photothermal properties of the present application is shown in the figure. DETAILED DESCRIPTION

[0028] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described in detail below. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the scope of protection of the present application.

[0029] Based on the accompanying drawings Figure 1 A preparation method of a titanium dioxide-based porous ceramic composite material with photothermal performance, comprising the following steps:

[0030] 1) Preparation of raw materials: after mixing titanium dioxide, graphite powder, steel slag, starch and adhesive, tabletting and drying treatment are carried out to obtain a mixture; wherein the mass ratio of titanium dioxide, graphite powder, steel slag, starch and adhesive is 1:0.5:2:0.25-0.75:1;

[0031] 2) Reduction roasting: the mixture of step 1) is subjected to reduction roasting to obtain a titanium dioxide-based porous ceramic composite material with photothermal performance.

[0032] It should be noted that the titanium dioxide-based porous ceramic composite material with photothermal performance is obtained by taking the material immediately after the reduction roasting is completed and cooling to room temperature.

[0033] In some examples, in step 1), the adhesive is polyvinyl alcohol (PVA).

[0034] In some examples, the adhesive is a polyvinyl alcohol solution with a mass percentage of 5-7wt%.

[0035] In some examples, in step 1), the starch is analytical pure starch; and the graphite powder is analytical pure graphite powder.

[0036] In some examples, the chemical composition and mass percentage of the steel slag are as follows:

[0037] MgO 7.08wt%, Al2O3 5.29wt%, SiO2 13.60wt%, P2O5 1.35wt%, CaO 42.10wt%, Fe2O3 26.70wt%, TiO2 0.91wt%, MnO 0.92wt%.

[0038] In some examples, in step 1), the crystal structure of the titanium dioxide is anatase type.

[0039] In some examples, the content of the anatase type crystal structure in the titanium dioxide is ≥98.5%.

[0040] In some examples, in step 1), a powder tabletting machine is used for tabletting.

[0041] In some examples, the pressure of the powder tablet press is 5-10 MPa.

[0042] In some examples, the temperature of the drying in step 1) is 120-150°C, and the time is 2-2.5 h.

[0043] In some examples, the temperature of the reduction roasting in step 1) is 800°C, and the time is 2 h.

[0044] In some examples, the reduction roasting in step 1) is performed in a crucible, and the mixed material is filled with a graphite layer on the upper and lower sides of the crucible.

[0045] In some examples, the thickness of the graphite layer is 1-2 cm.

[0046] In some examples, the crucible is a graphite crucible.

[0047] To further prove the effect of the titanium dioxide-based porous ceramic composite material with photothermal performance prepared by the preparation method of the application in improving the photothermal performance, the following examples and comparative examples are provided:

[0048] The chemical composition and content of the steel slag in the following examples are shown in Table 1.

[0049] Table 1

[0050]

[0051]

[0052] The graphite powder in the following examples is analytical pure graphite powder, and the starch is analytical pure starch.

[0053] The crystal structure of the titanium dioxide in the following examples is anatase type.

[0054] The binder in the following examples is a 5% polyvinyl alcohol (PVA) aqueous solution, which is an analytical pure polyvinyl alcohol and water according to the mass concentration.

[0055] Example 1

[0056] The present example provides a preparation method of a titanium dioxide-based porous ceramic composite material with photothermal performance, comprising the following steps:

[0057] 1. Mix 10 g of titanium dioxide, 5 g of graphite powder, 20 g of steel slag, 2.5 g of starch, and 10 g of binder to obtain a mixed material;

[0058] 2. Use a powder tablet press to press the mixed material into a tablet, and the pressure of the tablet is controlled to be 5 MPa to obtain a tablet-shaped mixed material.

[0059] 3. Dry the flake mixture in an electric heating forced-air drying oven at 120℃ for 2 hours to obtain a dried flake mixture;

[0060] 4. Place the dried flake mixture in a graphite crucible and cover the upper and lower sides of the dried flake mixture with a 1 cm thick graphite layer; place the graphite crucible containing the dried flake mixture in a high-temperature electric furnace and calcine at 800℃ for 2 hours. After calcination, immediately remove the material and cool it to obtain a titanium dioxide-based porous ceramic composite material.

[0061] The porosity of the titanium dioxide-based porous ceramic composite material sample in this embodiment was measured to be 14.33% using an electron densitometer.

[0062] A 500W long-arc xenon lamp was used as the light source, with a distance of 30cm between it and the sample. A control group without photothermal material was used, while the titanium dioxide-based porous ceramic composite material in this embodiment was used as the experimental group for photothermal performance testing. The average evaporation rate of the control group was 49.02gm. -2 min -1 The average evaporation rate of the experimental group was 63.03 gm. -2 min -1 .

[0063] The X-ray diffraction (XRD) results of the titanium dioxide-based porous ceramic composite material sample in this embodiment (hereinafter referred to as Example 1) are shown in the appendix. Figure 2 .

[0064] The UV-Vis absorption spectroscopy results of the titanium dioxide-based porous ceramic composite material sample in this embodiment (hereinafter referred to as Example 1) are shown in the appendix. Figure 3 .

[0065] Example 2

[0066] This embodiment provides a method for preparing a titanium dioxide-based porous ceramic composite material with photothermal properties, comprising the following steps:

[0067] 1. Take 10g of titanium dioxide, 5g of graphite powder, 20g of steel slag, 5g of starch and 10g of binder and mix them evenly to obtain a mixture;

[0068] 2. Use a powder tablet press to compress the mixture into tablets, controlling the pressing pressure to 5 MPa, to obtain tablet-shaped mixture;

[0069] 3. Dry the flake mixture in an electric heating forced-air drying oven at 120℃ for 2 hours to obtain a dried flake mixture;

[0070] 4. Put the dry sheet-shaped mixture into a graphite crucible, and cover the upper and lower sides of the dry sheet-shaped mixture with a 1 cm thick graphite layer; put the graphite crucible containing the dry sheet-shaped mixture into a high-temperature electric furnace, and calcine at 800 ℃ for 2 h; immediately after the calcination is completed, take out the material and cool it to obtain the titanium dioxide-based porous ceramic composite material.

[0071] The porosity of the titanium dioxide-based porous ceramic composite material sample in this embodiment is tested using an electronic density meter and is 17.74%.

[0072] The photothermal performance of the titanium dioxide-based porous ceramic composite material in this embodiment is tested using a 500 W long-arc xenon lamp as a light source, with a distance of 30 cm from the sample, and using a non-light-heat material as a control group; the average evaporation rate of the control group is 49.02 g -2 min -1 , and the average evaporation rate of the experimental group is 67.33 g -2 min -1 .

[0073] The X-ray diffraction (XRD) test results of the titanium dioxide-based porous ceramic composite material sample in this embodiment (referred to as Example 2) are shown in FIG. 2. Figure 2 .

[0074] The ultraviolet-visible light absorption spectrum test results of the titanium dioxide-based porous ceramic composite material sample in this embodiment (referred to as Example 2) are shown in FIG. 3. Figure 3 .

[0075] Embodiment 3

[0076] The embodiment provides a preparation method of a titanium dioxide-based porous ceramic composite material with photothermal performance, which comprises the following steps:

[0077] 1. Mix 10 g of titanium dioxide, 5 g of graphite powder, 20 g of steel slag, 7.5 g of starch, and 10 g of a binder to obtain a mixture;

[0078] 2. Use a powder tablet press to press the mixture into a sheet-shaped mixture, and the forming pressure is controlled to be 5 MPa;

[0079] 3. Dry the sheet-shaped mixture in an electric heating air drying oven at 120 ℃ for 2 h to obtain a dry sheet-shaped mixture;

[0080] 4. Put the dry sheet-shaped mixture into a graphite crucible, and cover the upper and lower sides of the dry sheet-shaped mixture with a 1 cm thick graphite layer; put the graphite crucible containing the dry sheet-shaped mixture into a high-temperature electric furnace, and calcine at 800 ℃ for 2 h; immediately after the calcination is completed, take out the material and cool it to obtain the titanium dioxide-based porous ceramic composite material.

[0081] The porosity of the sample of the titanium dioxide-based porous ceramic composite of this example was tested using an electronic densimeter and was 23.34%.

[0082] The photo-thermal performance of the sample was tested using a 500W long-arc xenon lamp as a light source, with a distance of 30cm from the sample, and using non-photo-thermal material as a control group and the titanium dioxide-based porous ceramic composite of this example as an experimental group. The average evaporation rate of the control group was 49.02g -2 min -1 , and the average evaporation rate of the experimental group was 75.20g -2 min -1 .

[0083] The X-ray diffraction (XRD) test results of the sample of the titanium dioxide-based porous ceramic composite of this example (Example 3) are shown in FIG. 6. Figure 2 .

[0084] The ultraviolet-visible light absorption spectrum test results of the sample of the titanium dioxide-based porous ceramic composite of this example (Example 3) are shown in FIG. 7. Figure 3 .

Claims

1. A method for preparing a porous titanium dioxide ceramic composite material with photothermal properties, characterized in that, Includes the following steps: 1) Material preparation: Take titanium dioxide, graphite powder, steel slag, starch and binder, mix them evenly, compress them into tablets and dry them to obtain a mixture; wherein, the mass ratio of titanium dioxide, graphite powder, steel slag, starch and binder is 1:0.5:2:0.25~0.75:1; 2) Reduction calcination: The mixture prepared in step 1) is subjected to reduction calcination to obtain a titanium dioxide-based porous ceramic composite material with photothermal properties.

2. The method for preparing the porous titanium dioxide ceramic composite material with photothermal properties according to claim 1, characterized in that: Step 1) Material preparation, wherein the adhesive is polyvinyl alcohol.

3. The method for preparing the porous titanium dioxide ceramic composite material with photothermal properties according to claim 2, characterized in that: The adhesive is a polyvinyl alcohol solution with a mass percentage of 5-7 wt%.

4. The method for preparing the porous titanium dioxide ceramic composite material with photothermal properties according to claim 1, characterized in that: Step 1) Material preparation: The starch is analytical grade starch; the graphite powder is analytical grade graphite powder; the chemical composition and mass percentage of the steel slag are as follows: MgO 7.08wt%, Al2O3 5.29wt%, SiO2 13.60wt%, P2O5 1.35wt%, CaO 42.10wt%, Fe2O326.70wt%, TiO2 0.91wt%, MnO 0.92wt%.

5. The method for preparing the porous titanium dioxide ceramic composite material with photothermal properties according to claim 1, characterized in that: Step 1) Material preparation: The titanium dioxide has anatase crystal structure.

6. The method for preparing the porous titanium dioxide ceramic composite material with photothermal properties according to claim 5, characterized in that: The content of anatase crystal structure in the titanium dioxide is ≥98.5%.

7. The method for preparing the porous titanium dioxide ceramic composite material with photothermal properties according to claim 1, characterized in that: Step 1) Material preparation: The tableting is performed using a powder tableting machine.

8. The method for preparing the porous titanium dioxide ceramic composite material with photothermal properties according to claim 7, characterized in that: The pressure of the powder tablet press is 5-10 MPa.

9. The method for preparing the porous titanium dioxide ceramic composite material with photothermal properties according to claim 1, characterized in that: Step 1) Prepare materials. The drying temperature is 120-150℃ and the time is 2-2.5h.

10. The method for preparing the porous titanium dioxide ceramic composite material with photothermal properties according to claim 1, characterized in that: Step 2) Reduction roasting, wherein the reduction roasting temperature is 800℃ and the time is 2h.

11. The method for preparing the porous titanium dioxide ceramic composite material with photothermal properties according to claim 1, characterized in that: Step 2) Reduction calcination, wherein the reduction calcination is carried out in a crucible, and the mixture is filled with graphite layers on both the upper and lower sides of the crucible.

12. The method for preparing the porous titanium dioxide ceramic composite material with photothermal properties according to claim 11, characterized in that: The thickness of the graphite layer is 1 to 2 cm.

13. The method for preparing the porous titanium dioxide ceramic composite material with photothermal properties according to claim 11, characterized in that: The crucible is a graphite crucible.

14. A porous titanium dioxide ceramic composite material with photothermal properties, made by the preparation method of the porous titanium dioxide ceramic composite material with photothermal properties according to any one of claims 1-13.

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