Preparation method of spinnable CeO2-ZrO2 sol and CeO2-ZrO2 ceramic fiber

Abstract

The invention discloses a spinnable CeO2-ZrO2 sol and a preparation method of CeO2-ZrO2 ceramic fibers. The preparation method of the spinnable CeO2-ZrO2 sol comprises the following steps: preparing zirconium polyacetylacetonate; preparing a first mixed solution from a zirconium polyacetylacetonate solution and cerium nitrate; adding a pore-forming agent and a seed crystal into the first mixed solution to prepare a second mixed solution; the second mixed solution is concentrated and aged, and a spinnable CeO2-ZrO2 sol is obtained; the solid content of the CeO2-ZrO2 sol with the spinnability is 30 to 50 percent; the mass fraction of the CeO2 is 8.6 to 36.8 percent, and the mass fraction of the ZrO2 is 3.1 to 26.3 percent; the cerium catalyst is high in catalytic efficiency, is fibrous and can be recycled, treated and repeatedly used after being used.

Description

Technical Field

[0001] The present invention relates to the field of cerium catalysts, and in particular to the field of a method for preparing spinnable CeO2-ZrO2 sol and CeO2-ZrO2 ceramic fibers. Background Art

[0002] Photocatalytic purification materials have become the main materials for decomposing and purifying pollutants in water, gas, and automobile exhaust. Cerium oxide has a face-centered cubic fluorite structure, which can release oxygen and convert into CeO2-x with oxygen vacancies. At the same time, Ce also has Ce3+ / Ce4+ valence change activity. As an emerging catalytic material, it can be used to oxidize and degrade organic wastewater, purify air, automobile exhaust, etc.

[0003] Existing cerium oxide catalysts are powdered photocatalysts, but when used in wastewater, exhaust gas, and automobile exhaust treatment, once the photocatalytic effect weakens, the powder is difficult to recover and regenerate in water, becoming solid waste that causes secondary pollution and has high usage costs.

[0004] Therefore, how to prepare a recyclable cerium oxide catalyst with high catalytic efficiency has become a difficult problem that needs to be solved urgently in this field. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for preparing a spinnable CeO2-ZrO2 sol and CeO2-ZrO2 ceramic fiber, which achieves high catalytic efficiency of the cerium catalyst and is in fibrous form and can be recovered, processed and reused after use.

[0006] One aspect of the present invention provides a method for preparing a spinnable CeO2-ZrO2 sol, comprising the following steps: preparing zirconium polyacetylacetonate;

[0007] preparing a first mixed solution by using a zirconium polyacetylacetonate solution and cerium nitrate;

[0008] Adding a pore-forming agent and a seed crystal into the first mixed solution to prepare a second mixed solution;

[0009] The second mixed solution is concentrated and aged to obtain a spinnable CeO2-ZrO2 sol; the spinnable CeO2-ZrO2 sol has a solid content of 30-50%; the mass fraction of CeO2 is 8.6-36.8%, and the mass fraction of ZrO2 is 3.1-26.3%; Ce 4+ Calculated based on CeO2, Zr 4+ Calculated as ZrO2.

[0010] The present invention has the beneficial effects over the prior art in that the spinnable CeO2-ZrO2 sol prepared by the spinnable CeO2-ZrO2 sol preparation method can be used to prepare CeO2-ZrO2 ceramic fibers, and the CeO2-ZrO2 ceramic fibers have high porosity and large specific surface area, so the catalytic efficiency is high, and the fibrous CeO2-ZrO2 can be screened and collected after use, and then processed for secondary use;

[0011] A first mixed solution is prepared by using a polyacetylacetonate zirconium solution and cerium nitrate, thereby preparing a spinnable CeO2-ZrO2 sol comprising CeO2 and ZrO2;

[0012] By adding a pore-forming agent and seed crystals to the first mixed solution to prepare a second mixed solution, the porosity of the subsequently prepared CeO2-ZrO2 ceramic fiber is high and the fiber contains long grains. This ultimately achieves a high specific surface area and high catalytic efficiency of the CeO2-ZrO2 ceramic fiber. However, the presence of long grains increases the strength and avoids problems such as fiber pulverization during recycling.

[0013] By concentrating and aging the second mixed solution, the CeO2-ZrO2 gel fiber prepared from the spinnable CeO2-ZrO2 sol has high strength, thereby avoiding problems such as fiber breakage or damage during the preparation of CeO2-ZrO2 ceramic fibers.

[0014] Furthermore, the preparation process of zirconium polyacetylacetonate comprises the following steps:

[0015] Mix zirconium n-propoxide and acetylacetone, stir at 50-80°C; then add deionized water dropwise, and continue stirring at 50-80°C for 0.5-2h after the addition is complete;

[0016] Then, the polymerization reaction is carried out at a temperature of 50-80° C. and a negative pressure environment for 0.5-3 hours to obtain orange-red zirconium polyacetylacetonate; the vacuum degree of the negative pressure environment is 0.95-0.98 bar.

[0017] The beneficial effect of the previous step is that by mixing zirconium n-propoxide and acetylacetone, stirring at 50-80°C and then adding deionized water, it is conducive to achieving high activity of zirconium n-propoxide and acetylacetone and starting prepolymerization. At the same time, by adding deionized water, energy accumulation in some parts of the temperature during prepolymerization is avoided, resulting in an excessively fast polymerization rate during subsequent polymerization, resulting in short molecular chains after polymerization, thereby reducing the strength of the prepared CeO2-ZrO2 ceramic fiber.

[0018] After adding deionized water, stirring at 50-80°C for 0.5-2h can avoid the activity reduction after adding deionized water; then polymerization reaction is carried out at 50-80°C under negative pressure environment to achieve stable polymerization and long polymer molecular chain length, which is conducive to achieving high strength of the subsequent CeO2-ZrO2 ceramic fiber.

[0019] Furthermore, the molar ratio of zirconium n-propoxide to acetylacetone is 1:(1-1.5), and the molar ratio of zirconium n-propoxide to deionized water is 1:(5-6).

[0020] Furthermore, the preparation process of the first mixed solution includes the following steps: adding zirconium polyacetylacetonate to an organic alcohol and then stirring at room temperature until it is completely dissolved; then adding cerium nitrate and stirring at room temperature to obtain a first mixed solution; the organic alcohol includes one or two saturated monohydric alcohols with 1-5 C atoms; the molar ratio of zirconium polyacetylacetonate to cerium nitrate is 1:(1-2).

[0021] The beneficial effect of adopting the above step is that the polyacetylacetonate zirconium is combined with the cerium element, and the combination is uniform.

[0022] Furthermore, the preparation process of the second mixed solution includes the following steps:

[0023] Stirring the pore-forming agent and the seed crystal in the first mixed solution in sequence to obtain a second mixed solution;

[0024] The pore-forming agent includes one or two of ammonium bicarbonate, urea, PVP, PEG, and PVA;

[0025] The seed crystal is hexagonal zirconia nanopowder;

[0026] The mass ratio of the polyacetylacetonate zirconium, the pore-forming agent and the seed crystal is 100:(10-25):(0.5-1).

[0027] The beneficial effect of the above step is that the porosity of the prepared CeO2-ZrO2 ceramic fiber is high by the pore-forming agent, thereby ultimately achieving a high specific surface area and high catalytic efficiency of the CeO2-ZrO2 ceramic fiber; the second mixed solution includes grains, and the seed crystal is hexagonal zirconia nanopowder, so that the CeO2-ZrO2 ceramic fiber contains long strip-shaped grains, thereby improving the strength of the CeO2-ZrO2 ceramic fiber;

[0028] By setting the mass ratio of the polyacetylacetonate zirconium, pore-forming agent and seed crystal to 100:(10-25):(0.5-1), the CeO2-ZrO2 ceramic fiber has a high specific surface area, high catalytic efficiency and high strength.

[0029] Furthermore, the preparation process of the second mixed solution further comprises the following steps:

[0030] The pore-forming agent and the seed crystal are sequentially added to the first mixed solution, followed by the addition of liquid wax, and the solution temperature is heated to maintain at 50-60° C. after the addition of the liquid wax; the mass ratio of the polyacetylacetonate zirconium to the liquid wax is 100:(1-5);

[0031] The liquid wax is C9-C 13 The latter is light liquid paraffin.

[0032] The beneficial effect of adopting the previous step is that the spinnable CeO2-ZrO2 sol is realized by adding liquid wax, and when the spinnable CeO2-ZrO2 sol is subsequently spun into yarn, the spinnable CeO2-ZrO2 sol is avoided from being spun into the surrounding environment, and at the same time, it is beneficial to improve the strength of the CeO2-ZrO2 gel fiber, and the liquid wax evaporates after sintering, thereby improving the porosity of the CeO2-ZrO2 ceramic fiber; at the same time, due to the light density of the liquid wax, when spinning, the liquid wax is located on the surface of the CeO2-ZrO2 gel fiber, so that when the glue is discharged, the liquid wax evaporates from the surface, i.e., pores are formed on the surface, and at the same time, it is beneficial for the pore-forming agent and other macromolecular organic volatiles inside the CeO2-ZrO2 gel fiber to volatilize through this channel, thereby avoiding the cracking of the CeO2-ZrO2 ceramic fiber, and at the same time, it is beneficial for the formation of uniform pores inside and outside the CeO2-ZrO2 ceramic fiber.

[0033] Furthermore, the preparation process of the second mixed solution further comprises the following steps:

[0034] Adding the pore-forming agent and the seed crystal to the first mixed solution in sequence, and then adding the heat curing system material and stirring to obtain the second mixed solution;

[0035] The thermal curing system materials include polymerization monomers, initiators, and cross-linking agents;

[0036] The polymerizable monomers include one or more of polyethylene glycol diacrylate, dipropylene glycol diacrylate, and 1,6-hexanediol diacrylate;

[0037] The cross-linking agent is N,N-methylenebisacrylamide; the initiator is one of di-tert-butyl peroxide and potassium persulfate.

[0038] Furthermore, the mass ratio of the poly(zirconium) acetylacetonate, the polymerization monomer, the initiator, and the cross-linking agent is 100:(5-10):(0.08-0.15):(0.1-0.3).

[0039] The beneficial effect of adopting the previous step is that, since the second mixed solution also includes a heat-curing system material, it is beneficial to improve the spinning performance of the spinnable CeO2-ZrO2 sol, improve the strength of the CeO2-ZrO2 gel fiber, and when the CeO2-ZrO2 gel fiber is heat-treated, the high molecular compound after the polymerization of the polymer monomer is volatilized, thereby increasing the porosity of the CeO2-ZrO2 ceramic fiber, thereby further increasing the specific surface area of ​​the CeO2-ZrO2 ceramic fiber, and ultimately improving the catalytic performance of the CeO2-ZrO2 ceramic fiber;

[0040] The polymerization monomers include one or more of polyethylene glycol diacrylate, dipropylene glycol diacrylate, and 1,6-hexanediol diacrylate, that is, the polymerization monomers contain two double bonds, so that the organic matter after polymerization has higher strength and is less difficult to volatilize; this is beneficial to improving the strength of the CeO2-ZrO2 gel fiber, and avoids damage or cracking of the CeO2-ZrO2 gel fiber when the high molecular organic matter after polymerization volatilizes.

[0041] Furthermore, the concentration aging process of the second mixed solution is to react the second mixed solution at a temperature of 60-130° C. in a negative pressure environment for 0.2-1 h; the vacuum degree of the negative pressure environment is 0.96-0.98 bar.

[0042] The beneficial effect of adopting the previous step is that by increasing the viscosity of the second mixed solution during the aging process, the spinning performance of the spinnable CeO2-ZrO2 sol is further improved, and it is also helpful to avoid the difficulty of volatilization of volatile substances in the subsequent CeO2-ZrO2 gel fiber.

[0043] Another aspect of the present invention provides a method for preparing CeO2-ZrO2 ceramic fibers, including a method for preparing a spinnable CeO2-ZrO2 sol;

[0044] The preparation of CeO2-ZrO2 ceramic fiber also includes the following steps:

[0045] The spinnable CeO2-ZrO2 sol is centrifugally spun at a temperature of 60-130°C and a rotation speed of 3000-5000 r / min to obtain CeO2-ZrO2 gel fiber;

[0046] The CeO2-ZrO2 gel fiber was heat treated in the following process: heating from room temperature to 90-110°C at a heating rate of 9-10°C / min; heating from 90-110°C to 220-230°C at a heating rate of 6-7°C / min; heating from 220-230°C to 280-320°C at a heating rate of 4-5°C / min; heating from 280-320°C to 580-620°C at a heating rate of 2-3°C / min;

[0047] The heat-treated CeO2-ZrO2 gel fiber is sintered at a temperature of 1-5°C / min to 1100-1300°C and kept at this temperature for 0.5-3h to obtain CeO2-ZrO2 ceramic fiber;

[0048] The CeO2-ZrO2 ceramic fiber component includes CeO2 with a mass fraction of 58.3-73.7% and ZrO2 with a mass fraction of 26.3-41.7%.

[0049] The present invention has the beneficial effects over the prior art in that a spinnable CeO2-ZrO2 sol is prepared by a spinnable CeO2-ZrO2 sol preparation method, and CeO2-ZrO2 ceramic fibers are prepared using the spinnable CeO2-ZrO2 sol; the CeO2-ZrO2 ceramic fibers have high porosity and large specific surface area, and thus high catalytic efficiency; and the fibrous CeO2-ZrO2 can be screened and collected after use, and then processed for secondary use;

[0050] CeO2-ZrO2 gel fiber can be obtained by centrifugally spinning spinnable CeO2-ZrO2 sol at a temperature of 60-130°C. The CeO2-ZrO2 gel fiber has high strength and will not be thrown into the surrounding environment.

[0051] By heating the temperature from room temperature to 90-110°C at a heating rate of 9-10°C / min, small molecular volatiles can be quickly volatilized to form through-holes with small pores; by heating the temperature from 90-110°C to 220-230°C at a heating rate of 6-7°C / min, larger molecular volatiles can be volatilized on the basis of the small pores formed by the small molecular volatiles to obtain channels with larger pores; by heating the temperature from 220-230°C to 280-320°C at a heating rate of 4-5°C / min, liquid wax can be volatilized in larger pores; by heating the temperature from 280-320°C to 580-620°C at a heating rate of 2-3°C / min, the macromolecular organic compounds formed by the polymerization monomers can be slowly decomposed, and after decomposition, they can be slowly volatilized on the basis of channels with larger pores, thereby achieving uniform pores, high porosity and high strength inside the CeO2-ZrO2 ceramic fiber. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is the GPC chart of zirconium polyacetylacetonate;

[0053] Figure 2 This is the SEM image of porous CeO2-ZrO2 ceramic fiber. DETAILED DESCRIPTION

[0054] In order to better understand the technical solution of the present invention, the present invention is further described below in conjunction with specific embodiments and the accompanying drawings.

[0055] Example 1:

[0056] One aspect of this embodiment provides a method for preparing a spinnable CeO2-ZrO2 sol, comprising the following steps:

[0057] Preparation of zirconium polyacetylacetonate; the preparation process of zirconium polyacetylacetonate comprises the following steps:

[0058] Mix zirconium n-propoxide and acetylacetone and stir at 65°C; then add deionized water dropwise, and continue stirring at 65°C for 1.3 hours after the addition is complete; the molar ratio of zirconium n-propoxide to acetylacetone is 1:1.2, and the molar ratio of zirconium n-propoxide to deionized water is 1:5.5;

[0059] Then, the polymerization reaction was carried out at a temperature of 65° C. and a negative pressure environment for 1.8 hours to obtain orange-red zirconium polyacetylacetonate; the vacuum degree of the negative pressure environment was 0.96 bar.

[0060] A first mixed solution is prepared by using a zirconium polyacetylacetonate solution and cerium nitrate. The preparation process of the first mixed solution includes the following steps: adding zirconium polyacetylacetonate to an organic alcohol and stirring at room temperature until it is completely dissolved; then adding cerium nitrate and stirring at room temperature to obtain the first mixed solution. The organic alcohol includes ethanol; and the molar ratio of the zirconium polyacetylacetonate to the cerium nitrate is 1:1.5.

[0061] A pore-forming agent and seed crystals are added to the first mixed solution to prepare a second mixed solution; the preparation process of the second mixed solution comprises the following steps:

[0062] Stirring the pore-forming agent and the seed crystal in the first mixed solution in sequence to obtain a second mixed solution;

[0063] The pore-forming agent includes ammonium bicarbonate and urea; the seed crystal is hexagonal zirconium oxide nanopowder; the mass ratio of the polyacetylacetonate zirconium, pore-forming agent and seed crystal is 100:18:0.8;

[0064] Adding the pore-forming agent and the seed crystal to the first mixed solution in sequence, and then adding the heat curing system material and stirring to obtain the second mixed solution;

[0065] The thermal curing system materials include polymerization monomers, initiators, and cross-linking agents;

[0066] The polymerizable monomer includes polyethylene glycol diacrylate;

[0067] The crosslinking agent is N,N-methylenebisacrylamide; the initiator is di-tert-butyl peroxide;

[0068] The mass ratio of the poly(zirconium) acetylacetonate, the polymerization monomer, the initiator, and the cross-linking agent is 100:8:0.11:0.2.

[0069] The second mixed solution is concentrated and aged to obtain a spinnable CeO2-ZrO2 sol; the process of concentrating and aging the second mixed solution is to react the second mixed solution at a temperature of 185°C and in a negative pressure environment for 0.6h; the vacuum degree of the negative pressure environment is 0.97bar.

[0070] The spinnable CeO2-ZrO2 sol has a solid content of 40%; the mass fraction of CeO2 is 22.7%, the mass fraction of ZrO2 is 14.7%; Ce 4+ Calculated based on CeO2, Zr 4+ Calculated as ZrO2.

[0071] Another aspect of the embodiment provides a method for preparing CeO2-ZrO2 ceramic fibers, including a method for preparing a spinnable CeO2-ZrO2 sol;

[0072] The preparation of CeO2-ZrO2 ceramic fiber also includes the following steps:

[0073] The spinnable CeO2-ZrO2 sol is centrifugally spun at a temperature of 95°C and a rotation speed of 4000 r / min to obtain CeO2-ZrO2 gel fibers;

[0074] The CeO2-ZrO2 gel fiber was heat treated in the following steps: from room temperature to 100℃, the heating rate was 9.5℃ / min; from 100℃ to 225℃, the heating rate was 6.5℃ / min; from 225℃ to 300℃, the heating rate was 4.5℃ / min; from 300℃ to 600℃, the heating rate was 2.5℃ / min;

[0075] The heat-treated CeO2-ZrO2 gel fiber was sintered at a temperature of 3°C / min to 1200°C and kept at that temperature for 1.8h to obtain CeO2-ZrO2 ceramic fiber.

[0076] The CeO2-ZrO2 ceramic fiber component includes 66% by mass of CeO2 and 34% by mass of ZrO2.

[0077] Example 2:

[0078] The same contents as those in Example 1 are not described in detail here. The differences between this embodiment and Example 1 are as follows:

[0079] One aspect of this embodiment provides a method for preparing a spinnable CeO2-ZrO2 sol, further comprising the following steps:

[0080] The preparation process of the second mixed solution further comprises the following steps:

[0081] The pore-forming agent and seed crystal are sequentially added to the first mixed solution, and then the liquid wax is added, and the solution temperature is maintained at 55°C after the addition of the liquid wax; the mass ratio of the polyacetylacetonate zirconium to the liquid wax is 100:3; the liquid wax is C9-C 13 The latter is light liquid paraffin.

[0082] Mix zirconium n-propoxide and acetylacetone and stir at 60°C; then add deionized water dropwise, and continue stirring at 60°C for 1.8 hours after the addition is complete; the molar ratio of zirconium n-propoxide to acetylacetone is 1:1.4, and the molar ratio of zirconium n-propoxide to deionized water is 1:5.8;

[0083] Then, the polymerization reaction was carried out at a temperature of 60° C. and a negative pressure environment for 2.8 hours to obtain orange-red zirconium polyacetylacetonate; the vacuum degree of the negative pressure environment was 0.97 bar.

[0084] The organic alcohol includes methanol; the molar ratio of the zirconium polyacetylacetonate to cerium nitrate is 1:1.8.

[0085] The pore-forming agent includes ammonium bicarbonate and PVA; the seed crystal is hexagonal zirconium oxide nanopowder; the mass ratio of the polyacetylacetonate zirconium, pore-forming agent and seed crystal is 100:12:0.6;

[0086] The polymerization monomers include polyethylene glycol diacrylate and dipropylene glycol diacrylate; the initiator is potassium persulfate;

[0087] The mass ratio of the polyacetylacetonate zirconium, the polymerization monomer, the initiator, and the cross-linking agent is 100:9:0.14:0.25.

[0088] The second mixed solution was reacted at a temperature of 120° C. under a negative pressure environment for 0.35 h; the vacuum degree of the negative pressure environment was 0.965 bar.

[0089] The spinnable CeO2-ZrO2 sol has a solid content of 45%; the mass fraction of CeO2 is 36.6%, the mass fraction of ZrO2 is 23%; Ce 4+ Calculated based on CeO2, Zr 4+ Calculated as ZrO2.

[0090] Another aspect of the embodiment provides a method for preparing CeO2-ZrO2 ceramic fibers, including a method for preparing a spinnable CeO2-ZrO2 sol;

[0091] The spinnable CeO2-ZrO2 sol is centrifugally spun at a temperature of 120°C and a rotation speed of 4500 r / min to obtain CeO2-ZrO2 gel fibers;

[0092] The CeO2-ZrO2 gel fiber was heat treated in the following steps: heating from room temperature to 105℃ at a heating rate of 9.8℃ / min; heating from 105℃ to 228℃ at a heating rate of 6.8℃ / min; heating from 228℃ to 310℃ at a heating rate of 4.8℃ / min; and heating from 310℃ to 610℃ at a heating rate of 2.8℃ / min.

[0093] The heat-treated CeO2-ZrO2 gel fiber was sintered at a temperature of 4°C / min to 1280°C and kept at that temperature for 0.8h to obtain CeO2-ZrO2 ceramic fiber.

[0094] The CeO2-ZrO2 ceramic fiber component includes 61.4% by mass of CeO2 and 38.6% by mass of ZrO2.

[0095] Example 3:

[0096] The same contents as those in Example 1 are not described in detail here. The differences between this embodiment and Example 1 are as follows:

[0097] One aspect of this embodiment provides a method for preparing a spinnable CeO2-ZrO2 sol, further comprising the following steps:

[0098] The preparation process of the second mixed solution further comprises the following steps:

[0099] The pore-forming agent and the seed crystal are sequentially added to the first mixed solution, followed by the addition of liquid wax, and the solution temperature is heated to maintain at 58° C. after the addition of the liquid wax; the mass ratio of the polyacetylacetonate zirconium to the liquid wax is 100:4.

[0100] Mix zirconium n-propoxide and acetylacetone and stir at 75°C; then add deionized water dropwise, and continue stirring at 75°C for 0.8h after the addition is complete; the molar ratio of zirconium n-propoxide to acetylacetone is 1:1.1, and the molar ratio of zirconium n-propoxide to deionized water is 1:5.2;

[0101] Then, the polymerization reaction was carried out at a temperature of 75° C. and a negative pressure environment for 0.8 h to obtain orange-red zirconium polyacetylacetonate; the vacuum degree of the negative pressure environment was 0.965 bar.

[0102] The organic alcohol includes ethanol and methanol; the molar ratio of the polyacetylacetonate zirconium to cerium nitrate is 1:1.2.

[0103] The pore-forming agent includes PVA; the mass ratio of the polyacetylacetonate zirconium, the pore-forming agent, and the seed crystal is 100:22:0.8;

[0104] The polymerizable monomers include polyethylene glycol diacrylate and 1,6-hexanediol diacrylate;

[0105] The initiator is potassium persulfate;

[0106] The mass ratio of the polyacetylacetonate zirconium, the polymerization monomer, the initiator, and the cross-linking agent is 100:6.5:1:0.15.

[0107] The second mixed solution was reacted at a temperature of 70° C. under a negative pressure environment for 0.9 h; the vacuum degree of the negative pressure environment was 0.97 bar.

[0108] The spinnable CeO2-ZrO2 sol has a solid content of 36%; the mass fraction of CeO2 is 10.5%, the mass fraction of ZrO2 is 5%; Ce 4+ Calculated based on CeO2, Zr 4+ Calculated as ZrO2.

[0109] Another aspect of the embodiment provides a method for preparing CeO2-ZrO2 ceramic fibers, including a method for preparing a spinnable CeO2-ZrO2 sol;

[0110] The spinnable CeO2-ZrO2 sol is centrifugally spun at a temperature of 70°C and a rotation speed of 3500 r / min to obtain CeO2-ZrO2 gel fiber;

[0111] The CeO2-ZrO2 gel fiber was heat treated in the following steps: heating from room temperature to 95℃ at a heating rate of 9.2℃ / min; heating from 95℃ to 222℃ at a heating rate of 6.2℃ / min; heating from 222℃ to 282℃ at a heating rate of 4.3℃ / min; and heating from 282℃ to 5805℃ at a heating rate of 2.3℃ / min.

[0112] The heat-treated CeO2-ZrO2 gel fiber was sintered at a temperature of 2°C / min to 1120°C and kept at that temperature for 2.8h to obtain CeO2-ZrO2 ceramic fiber.

[0113] The CeO2-ZrO2 ceramic fiber component includes 67.7% by mass of CeO2 and 32.3% by mass of ZrO2.

[0114] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of the invention herein is not limited to the technical solutions formed by the specific combination of the above-mentioned technical features, but also encompasses other technical solutions formed by any combination of the above-mentioned technical features or their equivalents without departing from the inventive concept. For example, the above-mentioned features may have similar functions to (but not limited to) those disclosed in this application.

Claims

1. A method for preparing a spinnable CeO2-ZrO2 sol, characterized in that: The following steps are involved: Preparation of zirconium polyacetylacetonate; preparing a first mixed solution by using a zirconium polyacetylacetonate solution and cerium nitrate; Adding a pore-forming agent and a seed crystal into the first mixed solution to prepare a second mixed solution; The second mixed solution is concentrated and aged to obtain a spinnable CeO2-ZrO2 sol; the spinnable CeO2-ZrO2 sol has a solid content of 30-50%; the mass fraction of CeO2 is 8.6-36.8%, and the mass fraction of ZrO2 is 3.1-26.3%.

2. The method for preparing a spinnable CeO2-ZrO2 sol according to claim 1, wherein: The preparation process of zirconium polyacetylacetonate comprises the following steps: Mix zirconium n-propoxide and acetylacetone, stir at 50-80°C; then add deionized water dropwise, and continue stirring at 50-80°C for 0.5-2h after the addition is complete; Then, the polymerization reaction is carried out at a temperature of 50-80° C. and a negative pressure environment for 0.5-3 hours to obtain orange-red zirconium polyacetylacetonate; the vacuum degree of the negative pressure environment is 0.95-0.98 bar.

3. The method for preparing a spinnable CeO2-ZrO2 sol according to claim 2, wherein: The molar ratio of zirconium n-propoxide to acetylacetone is 1:(1-1.5), and the molar ratio of zirconium n-propoxide to deionized water is 1:(5-6).

4. The method for preparing a spinnable CeO2-ZrO2 sol according to claim 1, wherein: The preparation process of the first mixed solution comprises the following steps: Add zirconium polyacetylacetonate to organic alcohol and stir at room temperature until completely dissolved; Then, cerium nitrate was added and stirred at room temperature to obtain a first mixed solution; The organic alcohol includes one or two of saturated monohydric alcohols with 1 to 5 C atoms; The molar ratio of the zirconium polyacetylacetonate to cerium nitrate is 1:(1-2).

5. The method for preparing spinnable CeO2-ZrO2 sol according to claim 1, characterized in that: The preparation process of the second mixed solution comprises the following steps: Stirring the pore-forming agent and the seed crystal in the first mixed solution in sequence to obtain a second mixed solution; The pore-forming agent includes one or two of ammonium bicarbonate, urea, PVP, PEG, and PVA; The seed crystal is hexagonal zirconia nanopowder; The mass ratio of the polyacetylacetonate zirconium, the pore-forming agent and the seed crystal is 100:(10-25):(0.5-1).

6. The method for preparing spinnable CeO2-ZrO2 sol according to claim 5, characterized in that: The preparation process of the second mixed solution further comprises the following steps: The pore-forming agent and the seed crystal are sequentially added to the first mixed solution, followed by the addition of liquid wax, and the solution temperature is heated to maintain at 50-60° C. after the addition of the liquid wax; the mass ratio of the polyacetylacetonate zirconium to the liquid wax is 100:(1-5); The liquid wax is C9-C 13 The latter is light liquid paraffin.

7. The method for preparing a spinnable CeO2-ZrO2 sol according to claim 1 or 5, characterized in that: The preparation process of the second mixed solution further comprises the following steps: Adding the pore-forming agent and the seed crystal to the first mixed solution in sequence, and then adding the heat curing system material and stirring to obtain the second mixed solution; The thermal curing system materials include polymerization monomers, initiators, and cross-linking agents; The polymerizable monomers include one or more of polyethylene glycol diacrylate, dipropylene glycol diacrylate, and 1,6-hexanediol diacrylate; The cross-linking agent is N,N-methylenebisacrylamide; the initiator is one of di-tert-butyl peroxide and potassium persulfate.

8. The method for preparing spinnable CeO2-ZrO2 sol according to claim 7, characterized in that: The mass ratio of the poly(zirconium) acetylacetonate, the polymerization monomer, the initiator, and the cross-linking agent is 100:(5-10):(0.08-0.15):(0.1-0.3).

9. The method for preparing spinnable CeO2-ZrO2 sol according to claim 1, characterized in that: The concentration aging process of the second mixed solution is to react the second mixed solution at a temperature of 60-130° C. in a negative pressure environment for 0.2-1 h; the vacuum degree of the negative pressure environment is 0.96-0.98 bar.

10. A method for preparing CeO2-ZrO2 ceramic fiber, characterized in that: A method for preparing a spinnable CeO2-ZrO2 sol comprising the steps of any one of claims 1 to 9; The preparation of CeO2-ZrO2 ceramic fiber also includes the following steps: The spinnable CeO2-ZrO2 sol is centrifugally spun at a temperature of 60-130°C and a rotation speed of 3000-5000 r / min to obtain CeO2-ZrO2 gel fiber; The CeO2-ZrO2 gel fiber was heat treated in the following process: heating from room temperature to 90-110°C at a heating rate of 9-10°C / min; heating from 90-110°C to 220-230°C at a heating rate of 6-7°C / min; heating from 220-230°C to 280-320°C at a heating rate of 4-5°C / min; heating from 280-320°C to 580-620°C at a heating rate of 2-3°C / min; The heat-treated CeO2-ZrO2 gel fiber is sintered at a temperature of 1-5°C / min to 1100-1300°C and kept at this temperature for 0.5-3h to obtain CeO2-ZrO2 ceramic fiber; The CeO2-ZrO2 ceramic fiber component includes CeO2 with a mass fraction of 58.3-73.7% and ZrO2 with a mass fraction of 26.3-41.7%.

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