CN102701273A - Preparation method of nano dysprosium titanate powder - Google Patents
Preparation method of nano dysprosium titanate powder Download PDFInfo
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- CN102701273A CN102701273A CN2012101601586A CN201210160158A CN102701273A CN 102701273 A CN102701273 A CN 102701273A CN 2012101601586 A CN2012101601586 A CN 2012101601586A CN 201210160158 A CN201210160158 A CN 201210160158A CN 102701273 A CN102701273 A CN 102701273A
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Abstract
The invention relates to a preparation method of nano dysprosium titanate powder. The method comprises the steps of dropping alcohol/water/glacial acetic acid mixed solution containing dysprosium nitrate into titanium acid butyl ester alcohol solution according to the molar ratio of Dy:Ti=(1-2:1); ageing obtained colloidal sol at the room temperature so as to obtain gel; drying and crushing the gel, arranging the gel into an aluminum oxide crucible, sintering the gel at 8001100 DEG C so as to obtain the nano dysprosium titanate powder. The nano dysprosium titanate powder preparation process is simple, the grain size of the powder is even and small, and the purity is high; and the powder can be used as neutron absorbing materials.
Description
Technical field
The present invention relates to a kind of preparation method who is used as the nano barium titanate dysprosium powder of neutron absorbing material, belong to neutron absorbing material technical field.
Background technology
The main effect of nuclear radiation shield material is absorption or weakens neutron and gamma-rays.In nuclear reactor, be thermal neutron or epithermal neutrons by slowing down through the neutron major part behind pressure vessel and the gas-tight silo, this type of neutron needs the bigger material of thermal neutron absorption cross section effectively to absorb and is unlikely to overflow.
The B10 isotropic substance has very big thermal neutron absorption cross section, thus in nuclear industry norbide and boron steel is used in the rod and as shielding material.But, owing to B when radiation
10Take place (n, α) reaction makes these materials behind irradiation, occur " expansion ", the formation nuclear vacuole.For boron carbide ceramics, irradiation " expansion " can cause the inefficacy of covering.Therefore, in the work-ing life of absorbing material, be decided by the irradiation stability of material rather than the decline of neutron assimilated efficiency to a great extent.In view of more than, hope to utilize and to take place (n, α) the alternative boron materials of stupalith such as the dysprosium of reaction and absorption thermal neutron, europium, samarium, gadolinium, hafnium base.The irradiation experiment of pottery absorbing material shows that fluorite type lanthanide oxide base pottery demonstrates best Antiradiation injury property.In these materials; The metatitanic acid dysprosium once was used in Muscovite water-water power reactor 15 years [referring to Amit Sinha and Beant Prakash Sharma.Development of Dysprosium Titanate Based Ceramics; J.Am.Ceram.Soc., 88 [4] 1064 – 1066 (2005)].Metatitanic acid dysprosium pottery as the neutron absorbing material except high neutron assimilated efficiency; Do not have very big swelling, under neutron radiation, do not exit, HMP (~ 1870 ° of C) and more than 1000 ℃ not with the coating effect etc., can be with ball ball or particulate state as rod.
V.D.Risovany etc. are with Dy
2O
3, TiO
2Be raw material; An amount of metal molybdenum of admixture; Metatitanic acid dysprosium powder has been synthesized in high-temperature calcination, referring to V.D.Risovany, and E.E.Varlashova; D.N.Suslov.Dysprosium titanate as an absorber material for control rods.Journal ofNuclear Materials, 281 (2000) 84-89; People such as Amit Sinha are also with Dy
2O
3, TiO
2Be raw material; Through adding an amount of molybdenum oxide as stablizer; Calcining obtained metatitanic acid dysprosium powder in 4 hours under 1600 ℃, and mean particle size is more than 5 μ m, referring to Amit Sinha and Beant Prakash Sharma.Development of Dysprosium Titanate Based Ceramics; J.Am.Ceram.Soc., 88 [4] 1064 – 1066 (2005).Adopt the solid phase method reaction method can synthesize metatitanic acid dysprosium powder, but with respect to chemical process, the particle diameter of synthetic powder is big, mixes impurity easily.
Summary of the invention
To the deficiency of prior art, the present invention provides a kind of method for preparing high purity, evengranular nano barium titanate dysprosium powder.
Technical scheme of the present invention is following:
A kind of preparation method of nano barium titanate dysprosium powder, step is following:
(1) butyl(tetra)titanate is under agitation joined in the absolute ethyl alcohol, the volume ratio of butyl(tetra)titanate and absolute ethyl alcohol is 0.5 ~ 3:1, gets the butyl(tetra)titanate alcoholic solution;
(2) it is even absolute ethyl alcohol to be joined deionized water for stirring, absolute ethyl alcohol and deionized water volume ratio 3: (1～2), alcohol solution, add hydrochloric acid and regulate pH 0 ~ 3; Add Glacial acetic acid min. 99.5 and Dysprosium trinitrate, stirring is dissolved it fully, processes the mixing solutions that Dysprosium trinitrate content is 40-65wt%; The dosage of Glacial acetic acid min. 99.5 is the 3-13wt% of Dysprosium trinitrate weight;
(3) Dy:Ti=1 ~ 2:1 in molar ratio is added drop-wise to the mixing solutions that contains Dysprosium trinitrate of step (2) in the butyl(tetra)titanate alcoholic solution of step (1), fully stir, mixed sols;
(4) mixed sols that step (3) is made is ageing 20～30h at room temperature, obtains gel; Then that gel is dry under 50～80 ℃, pulverize, cross 100～200 mesh sieves, obtain metatitanic acid dysprosium presoma xerogel powder;
(5) metatitanic acid dysprosium presoma xerogel is packed in the alumina crucible, at 800～1100 ℃ temperature lower calcination, insulation 0.5 ~ 2h obtains nano barium titanate dysprosium powder.
Preferably, the volume ratio of the butyl(tetra)titanate of said step (1) and absolute ethyl alcohol is 1 ~ 2.5:1;
In the said step (2), preferred absolute ethyl alcohol and deionized water volume ratio 3: (1～1.5), and pH=0 ~ 2, mol ratio Dy:Ti is 1 ~ 1.2:1; The metering specific energy of strict control dysprosium and titanium improves product purity well.
Preferably, the calcining temperature of said step (5) is incubated 1 ~ 2h at 850 ~ 1000 ℃.
But the raw material among the present invention is all buied in market, and wherein Dysprosium trinitrate can directly be bought the commercially available prod, also can make the Dysprosium trinitrate powder through dysprosium oxide and nitric acid reaction, drying by prior art.
Nano barium titanate dysprosium powder of the present invention is to be raw material with Dysprosium trinitrate and butyl(tetra)titanate, adopts chemical sol-gel technology to prepare metatitanic acid dysprosium presoma xerogel, and high-temperature calcination is prepared from the alumina-ceramic crucible then; The present invention in Dysprosium trinitrate solution, add an amount of Glacial acetic acid min. 99.5 when being added in the Dysprosium trinitrate solution to slow down the butyl(tetra)titanate drips of solution butyl(tetra)titanate hydrolysis with polymeric speed.This method technology is simple, in conjunction with sol gel process can prepare advantages such as the less and size distribution of powder crystal grain is even, under relatively low temperature, synthesized metatitanic acid dysprosium nano-powder.Compare with solid reaction process and the invention has the advantages that:
1. the raw material of the synthetic metatitanic acid dysprosium use of the present invention is easy to get, and mild condition does not increase raw material and technology cost;
2. dysprosium can strict be controlled with the element metering ratio of titanium in the synthetic metatitanic acid dysprosium process of the present invention, and product purity is high;
3. the synthetic metatitanic acid dysprosium powder crystallization formation temperature of the present invention is lower;
4. the metatitanic acid dysprosium powder granularity prepared of the present invention is even, and particle diameter is at the nano level yardstick;
The nano barium titanate dysprosium powder of the present invention's preparation can be used for preparing the metatitanic acid dysprosium neutron absorbing material of fine crystalline structure, can be used as the stupalith of command bundle rods for nuclear reactors, regulating rod, emergency rod, safety rod, shielding rod.
Description of drawings
Fig. 1 is the SEM figure of the metatitanic acid dysprosium powder of embodiment 3 preparations.
Fig. 2 is the XRD figure of the metatitanic acid dysprosium powder of embodiment 3 preparations.
Embodiment
Below in conjunction with embodiment the present invention is described further, but is not limited thereto.
Embodiment 1: mol ratio Dy:Ti=1:1
1, the 40ml butyl(tetra)titanate is joined in the 20ml absolute ethyl alcohol when stirring, get the butyl(tetra)titanate alcoholic solution;
2, it is even the 30ml absolute ethyl alcohol to be joined the 10ml deionized water for stirring, and adding hydrochloric acid, to regulate pH be 2; Add the 4ml Glacial acetic acid min. 99.5 to slow down butyl(tetra)titanate hydrolysis and polymeric speed, in solution, add the 41g Dysprosium trinitrate then, stirring is dissolved it fully, gets Dysprosium trinitrate solution;
3, the Dysprosium trinitrate solution with step 2 slowly is added drop-wise in the broad liquid of butyl(tetra)titanate of step 1, fully stirs, and gets mixed sols;
4, the mixed sols that step 3 is made is ageing 24h at room temperature, obtains gel; Then that gel is dry under 80 ℃, pulverize, cross 100 mesh sieves, obtain metatitanic acid dysprosium presoma xerogel powder;
5, metatitanic acid dysprosium presoma xerogel is packed in the alumina crucible, put into retort furnace, pressureless sintering under 900 ℃ temperature, insulation 1h obtains 48g metatitanic acid dysprosium nanopowder.
The granularity of the metatitanic acid dysprosium powder that obtains is about 80nm, and purity is more than 97%, and yield is about 90%.
Embodiment 2: mol ratio Dy: Ti=1.7:1
1, the 40ml butyl(tetra)titanate is joined in the 40ml absolute ethyl alcohol when stirring, get butyl(tetra)titanate solution;
2, it is even the 30ml absolute ethyl alcohol to be joined the 20ml deionized water for stirring, and adding hydrochloric acid, to regulate pH be 1.5; Add the 2ml Glacial acetic acid min. 99.5 to slow down butyl(tetra)titanate hydrolysis and polymeric speed, Dy:Ti is 1.7:1 in molar ratio, in solution, adds the 69.7g Dysprosium trinitrate, stirs it is dissolved fully, gets Dysprosium trinitrate solution;
3, the Dysprosium trinitrate solution with step 2 slowly is added drop-wise in the broad liquid of butyl(tetra)titanate of step 1, fully stirs, and gets mixed sols;
4, the mixed sols that step 3 is made is ageing 24h at room temperature, obtains gel; Then that gel is dry under 50 ℃, pulverize, cross 200 mesh sieves, obtain metatitanic acid dysprosium presoma xerogel powder;
5, metatitanic acid dysprosium presoma xerogel is packed in the alumina crucible, be put into pressureless sintering in the sintering oven, 5 ℃/min of heat-up rate, top temperature is 900 ℃, and insulation 1h is a protective gas with the argon gas, and naturally cooling obtains 42g metatitanic acid dysprosium nanopowder.
The granularity of the metatitanic acid dysprosium powder that obtains is about 100nm, and purity is more than 87%, and yield is about 78%.
Embodiment 3: mol ratio Dy:Ti=1.2:1
1, the 40ml butyl(tetra)titanate is joined in the 20ml absolute ethyl alcohol when stirring, get butyl(tetra)titanate solution;
2, it is even the 20ml absolute ethyl alcohol to be joined the 10ml deionized water for stirring, and adding hydrochloric acid, to regulate pH be 0.5～1; Add the 3ml Glacial acetic acid min. 99.5 to slow down butyl(tetra)titanate hydrolysis and polymeric speed, Dy:Ti is 1.2:1 in molar ratio, in solution, adds the 49g Dysprosium trinitrate, stirs it is dissolved fully, gets Dysprosium trinitrate solution;
3, the Dysprosium trinitrate solution with step 2 slowly is added drop-wise in the broad liquid of butyl(tetra)titanate of step 1, fully stirs, and gets mixed sols;
4, the mixed sols that step 3 is made is ageing 24h at room temperature, obtains gel; Then that gel is dry under 70 ℃, pulverize, cross 100 mesh sieves, obtain metatitanic acid dysprosium presoma xerogel powder;
5, metatitanic acid dysprosium presoma xerogel is packed in the alumina crucible, discharge plasma sintering in the sintering oven of packing into, top temperature is 1000 ℃, insulation 0.5h, naturally cooling obtains 44g metatitanic acid dysprosium nanopowder.
The granularity of the metatitanic acid dysprosium powder that obtains is about 100nm, and purity is more than 95%, and yield is about 82%.
Claims (4)
1. the preparation method of a nano barium titanate dysprosium powder, step is following:
(1) butyl(tetra)titanate is under agitation joined in the absolute ethyl alcohol, the volume ratio of butyl(tetra)titanate and absolute ethyl alcohol is 0.5 ~ 3:1, gets the butyl(tetra)titanate alcoholic solution;
(2) it is even absolute ethyl alcohol to be joined deionized water for stirring, absolute ethyl alcohol and deionized water volume ratio 3: (1～2), alcohol solution, add hydrochloric acid and regulate pH 0 ~ 3; Add Glacial acetic acid min. 99.5 and Dysprosium trinitrate, stirring is dissolved it fully, processes the mixing solutions that Dysprosium trinitrate content is 40-65wt%; The dosage of Glacial acetic acid min. 99.5 is the 3-13wt% of Dysprosium trinitrate weight;
(3) Dy:Ti=1 ~ 2:1 in molar ratio is added drop-wise to the mixing solutions that contains Dysprosium trinitrate of step (2) in the butyl(tetra)titanate alcoholic solution of step (1), fully stir, mixed sols;
(4) mixed sols that step (3) is made is ageing 20～30h at room temperature, obtains gel; Then that gel is dry under 50～80 ℃, pulverize, cross 100～200 mesh sieves, obtain metatitanic acid dysprosium presoma xerogel powder;
(5) metatitanic acid dysprosium presoma xerogel is packed in the alumina crucible, at 800～1100 ℃ temperature lower calcination, insulation 0.5 ~ 2h obtains nano barium titanate dysprosium powder.
2. the preparation method of nano barium titanate dysprosium powder as claimed in claim 1 is characterized in that the butyl(tetra)titanate of step (1) and the volume ratio of absolute ethyl alcohol are 1 ~ 2.5:1.
3. the preparation method of nano barium titanate dysprosium powder as claimed in claim 1 is characterized in that in the step (2) absolute ethyl alcohol and deionized water volume ratio 3: (1～1.5), pH=0 ~ 2, mol ratio Dy:Ti is 1 ~ 1.2:1.
4. the preparation method of nano barium titanate dysprosium powder as claimed in claim 1, the calcining temperature that it is characterized in that step (5) are incubated 1 ~ 2h at 850 ~ 1000 ℃.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104477977A (en) * | 2014-12-11 | 2015-04-01 | 山东大学 | Method for synthesizing Dy2TiO5 powder by molten-salt growth method |
| CN105161144A (en) * | 2015-08-07 | 2015-12-16 | 厦门大学 | Preparation method of dysprosium titanium oxide pellet serving as neutron absorbing material of nuclear reactor core |
| CN107188558A (en) * | 2017-07-20 | 2017-09-22 | 陕西师范大学 | A kind of alumina doped copper titanate cadmium giant dielectric ceramic material of high energy storage density and preparation method thereof |
| CN107216142A (en) * | 2017-07-20 | 2017-09-29 | 陕西师范大学 | A kind of high thermal stability copper titanate cadmium X8R ceramic materials |
| CN107216147A (en) * | 2017-07-20 | 2017-09-29 | 陕西师范大学 | A kind of high breakdown field strength zirconia titanate copper cadmium giant dielectric ceramic material and preparation method thereof |
| CN108439462A (en) * | 2018-03-28 | 2018-08-24 | 江苏师范大学 | A kind of preparation method of pyrochlore-type rare earth titanate powder |
| CN113213916A (en) * | 2021-05-19 | 2021-08-06 | 山东大学 | Fluorite-structured dysprosium titanate reactor control rod and preparation method thereof |
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| CN1803629A (en) * | 2006-01-12 | 2006-07-19 | 景德镇陶瓷学院 | Method for preparing modified aluminium titanate material |
| CN101423243A (en) * | 2008-11-25 | 2009-05-06 | 北京科技大学 | La doped SrTiO3 base oxide pyroelectric material and preparation method |
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| WO2004028971A1 (en) * | 2002-09-24 | 2004-04-08 | Beijing University Of Chemical Technology | The process for preparing a strontium titanate powder |
| CN1803629A (en) * | 2006-01-12 | 2006-07-19 | 景德镇陶瓷学院 | Method for preparing modified aluminium titanate material |
| CN101423243A (en) * | 2008-11-25 | 2009-05-06 | 北京科技大学 | La doped SrTiO3 base oxide pyroelectric material and preparation method |
Cited By (14)
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|---|---|---|---|---|
| CN104477977A (en) * | 2014-12-11 | 2015-04-01 | 山东大学 | Method for synthesizing Dy2TiO5 powder by molten-salt growth method |
| CN104477977B (en) * | 2014-12-11 | 2016-05-11 | 山东大学 | The synthetic Dy of a kind of molten-salt growth method2TiO5The method of powder |
| CN105161144A (en) * | 2015-08-07 | 2015-12-16 | 厦门大学 | Preparation method of dysprosium titanium oxide pellet serving as neutron absorbing material of nuclear reactor core |
| CN105161144B (en) * | 2015-08-07 | 2017-09-08 | 厦门大学 | A kind of preparation method of nuclear reactor neutron absorber material metatitanic acid dysprosium pellet |
| CN107216147A (en) * | 2017-07-20 | 2017-09-29 | 陕西师范大学 | A kind of high breakdown field strength zirconia titanate copper cadmium giant dielectric ceramic material and preparation method thereof |
| CN107216142A (en) * | 2017-07-20 | 2017-09-29 | 陕西师范大学 | A kind of high thermal stability copper titanate cadmium X8R ceramic materials |
| CN107188558A (en) * | 2017-07-20 | 2017-09-22 | 陕西师范大学 | A kind of alumina doped copper titanate cadmium giant dielectric ceramic material of high energy storage density and preparation method thereof |
| CN107216147B (en) * | 2017-07-20 | 2019-10-25 | 陕西师范大学 | A kind of high breakdown field strength zirconia titanate copper cadmium giant dielectric ceramic material and preparation method thereof |
| CN107216142B (en) * | 2017-07-20 | 2019-10-25 | 陕西师范大学 | A kind of high thermal stability copper titanate cadmium X8R ceramic material |
| CN107188558B (en) * | 2017-07-20 | 2019-10-25 | 陕西师范大学 | A kind of alumina doped copper titanate cadmium giant dielectric ceramic material of high energy storage density and preparation method thereof |
| CN108439462A (en) * | 2018-03-28 | 2018-08-24 | 江苏师范大学 | A kind of preparation method of pyrochlore-type rare earth titanate powder |
| CN108439462B (en) * | 2018-03-28 | 2020-09-22 | 新沂市东方硕华光学材料有限公司 | Preparation method of pyrochlore type rare earth titanate powder |
| CN113213916A (en) * | 2021-05-19 | 2021-08-06 | 山东大学 | Fluorite-structured dysprosium titanate reactor control rod and preparation method thereof |
| CN113213916B (en) * | 2021-05-19 | 2022-02-11 | 山东大学 | Fluorite-structured dysprosium titanate reactor control rod and preparation method thereof |
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