CN103191712B - Cerium oxide and zirconium oxide based composite rare earth oxide with favorable ageing resistance and high reduction activity and preparation method of cerium oxide and zirconium oxide based composite rare earth oxide - Google Patents

Cerium oxide and zirconium oxide based composite rare earth oxide with favorable ageing resistance and high reduction activity and preparation method of cerium oxide and zirconium oxide based composite rare earth oxide Download PDF

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CN103191712B
CN103191712B CN201310116959.7A CN201310116959A CN103191712B CN 103191712 B CN103191712 B CN 103191712B CN 201310116959 A CN201310116959 A CN 201310116959A CN 103191712 B CN103191712 B CN 103191712B
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oxide
cerium
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earth oxide
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CN103191712A (en
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肖景鲁
黄壮昌
郭喜斌
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Chaozhou Three Circle Group Co Ltd
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    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/0009—Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F17/00—Compounds of rare earth metals
    • C01F17/30—Compounds containing rare earth metals and at least one element other than a rare earth metal, oxygen or hydrogen, e.g. La4S3Br6
    • C01F17/32—Compounds containing rare earth metals and at least one element other than a rare earth metal, oxygen or hydrogen, e.g. La4S3Br6 oxide or hydroxide being the only anion, e.g. NaCeO2 or MgxCayEuO
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Abstract

The invention discloses a preparation method of a cerium oxide and zirconium oxide based composite rare earth oxide. The method comprises the following steps of: (1) weighting zircon salt with a certain mass and preparing a zircon salt solution; (2) mixing urea and sulfuric acid or sulfate to prepare an activating agent solution; (3) heating the zircon salt solution under the room temperature, meanwhile, slowly and dropwise adding the activating agent solution, controlling the temperature rise speed to ensure that the temperature is raised to 60 DEG C after the addition of the activating agent solution is finished, continuing to raising the temperature to 90-95 DEG C, and keeping the temperature for 20-100min to form a basic zirconium sulfate composite salt precursor solution; (4) preparing soluble cerate and rare earth metal salt, adding the soluble cerate and the rare earth metal salt into the basic zirconium sulfate composite salt precursor solution, and settling by using a soluble hydroxide or an aqueous solution of ammonia; and (5) filtering and cleaning precipitates, and then, calcining the precipitates to obtain the cerium oxide and zirconium oxide based composite rare earth oxide. The cerium oxide and zirconium oxide based composite rare earth oxide prepared by using the method provided by the invention has favorable ageing resistance and high reduction activity.

Description

A kind of cerium oxide zirconia base composite rare-earth oxide and preparation method thereof with good ageing resistace, high reducing activity
Technical field
The present invention relates to a kind of cerium oxide zirconia base composite rare-earth oxide and preparation method thereof, especially a kind of cerium oxide zirconia base composite rare-earth oxide and preparation method thereof with good ageing resistace, high reducing activity.
Background technology
Because the exhaust emissions of automobile, motorcycle and the tractor particularly motor vehicle such as automobile has become the main source of atmospheric pollution in big and medium-sized cities, the world, and controller motor-car pollution emission, most effective measures are the outer automobile exhaust purifiers of fitting machine.As the active carbon layer of automobile exhaust purifier carrier, cerium pick composite has become the indispensable material of automobile catalyst.Cerium pick composite has good oxygen storage capacity and high-temperature hydrothermal stability, effectively can widen the air-fuel ratio window of auto-exhaust catalyst, improves the performance and used life of catalyst.Particularly cerium pick can improve the decentralization of precious metal catalyst particle and the availability of noble metal, reduces noble metal dosage, thus reduces the preparation cost of catalyst.Cerium pick composite oxides both effectively can reduce the atmosphere pollution that motor vehicle exhaust emission causes, and can promote again the industry of pick chemicals and ZrO 2product develops to field of deep, also the structural adjustment of promotion rare-earth products is transformed to high value added product.
Cerium zirconium compound catalyze material has the advantages that high stable, high reducing power and height store oxygen ability, makes three-way catalyst have very high low-temperature catalyzed conversion capability.Its excellent properties derives from the special electronic structure of rare earth in characteristic.Cerium has valence state changeability, excess of oxygen can be stored and be converted into quadrivalent cerium, promote the reduction purification of waste gas under oxygen enrichment state.When oxygen deprivation, can oxygen evolution be transferred to trivalent cerium, promote the oxidation, purification of waste gas.And ZrO 2the high-temperature stability of material can be improved, keep the specific area that material is higher.CeO 2and ZrO 2can compound in very large ratio range, form stable cerium zirconium sosoloid, there is the characteristic advantage not available for single Ce, Zr.In addition, in cerium oxide, ZrO is mixed 2with the cubic fluorite structure of stable cerium oxide, the high-temperature stability of catalyst can be improved, reduce Ce 4+activation energy and the initial reduction temperature of phase body, make the oxygen storage capacity of cerium zirconia material (OSC) have higher conversion efficiency in larger temperature range.
The interpolation of different proportion rare earth element prevents the growth of cerium zirconium crystal grain, and the high temperature sintering phenomenon that inhibit catalyst and the effect causing catalyst activity significantly to reduce thereof, improve the high high-temp stability of catalyst.In order to the discharge standard of the combustion conditions and increasingly stringent that meet Automobile Complex, auto-exhaust catalyst generally uses under high-speed and high temperature (sometimes reaching more than 1000 DEG C) condition, and its installation site is more and more close to engine, and serviceability temperature is more and more higher.Cerium Zr catalyst prepared by conventional method at high temperature can keep good Oxygen storage capacity, the requirement of high-performing car tail gas clean-up three-way catalyst to hydrogen-storing material Oxygen storage capacity and high-temperature stability thereof can be met, but cerium zirconium sosoloid at high temperature structure is thermally-stabilised poor, and specific area is less than normal.As reported, prepared cerium zirconium hydrogen-storing material is after 1000 DEG C of roasting 4hr, and at 200 DEG C, oxygen storage capacity still can reach 300 μm of more than ol/g, but specific area is less than 10g/m 2.Three-way catalyst must have stronger durability under high-speed, and conventional cerium zirconia material dissociates Tetragonal ZrO at relatively high temperatures 2, make single cubic phase transition be multiphase coexistence, be separated and can cause the degradation of catalyst performance with the instability of texture property.
Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art part and provide a kind of total pore to hold large, fresh specific area is high, specific area Heat stability is good at high temperature, have the cerium oxide zirconia base composite rare-earth oxide of good ageing resistace and high reducing activity; Meanwhile, present invention also offers the preparation method of described cerium oxide zirconia base composite rare-earth oxide.
For achieving the above object, the technical scheme that the present invention takes is: a kind of preparation method of cerium oxide zirconia base composite rare-earth oxide, comprises the following steps:
(1) solubility zirconates is prepared: take certain mass zirconates, zirconates is water-soluble, be mixed with zirconium salt solution;
(2) activator solution is prepared: urea and sulfuric acid or sulfate are hybridly prepared into activator solution, the mass ratio of wherein said urea and the middle zirconates of step (1) is 1:99 ~ 2:98, and the mass ratio of described sulfate radical and the middle zirconates of step (1) is 1:3 ~ 3:5;
(3) under room temperature, the zirconium salt solution in step (1) is heated, slowly drip the activator solution in step (2) simultaneously, control programming rate, when activator solution is dropwised, temperature rises to 60 DEG C, then continue to heat up, be warming up to 90 ~ 95 DEG C from 60 DEG C in 30min, insulation 20 ~ 100min, form zirconium basic sulphate complex salt precursor solution;
(4) prepare solubility cerium salt and rare earth metal salt, and described solubility cerium salt and rare earth metal salt are added in the zirconium basic sulphate complex salt precursor solution of step (3) gained, then precipitate with soluble hydroxide or ammonia spirit, obtain sediment;
(5) by step (4) gained sediment filtration washing, then calcine, obtain cerium oxide zirconia base composite rare-earth oxide.
Present inventor is through studying widely, and found through experiments, by the activator solution in configuration step (2), described activator solution is slowly joined in soluble zirconium salting liquid, constantly heat up in the process dripped, when temperature rises to 60 DEG C, the urea in activator decomposes, sulfate ion and pick ion react simultaneously, control hydrolysis of urea become NH by control programming rate 3and CO 2speed, the NH of generation 3and CO 2play the effect of pore-creating and dispersion, make the zirconium basic sulphate complex salt presoma that finally can form short texture porous, improve its reactivity; In described zirconium basic sulphate complex salt presoma, add cerium salt and rare earth metal salt solutions, then add alkali reaction and generate cerium pick class rare-earth hydroxide, thus form good cerium pick solid solution, improve ageing resistance and the reproducibility of products obtained therefrom.
As the preferred embodiment of the preparation method of cerium oxide zirconia base composite rare-earth oxide of the present invention, the zirconates in described step (1) is at least one in zirconium oxychloride, zirconyl nitrate and oxalic acid zirconium.
As the preferred embodiment of the preparation method of cerium oxide zirconia base composite rare-earth oxide of the present invention, the sulfate in described step (2) is at least one in sodium sulphate, potassium sulfate, ammonium sulfate.
As the preferred embodiment of the preparation method of cerium oxide zirconia base composite rare-earth oxide of the present invention, the solubility cerium salt in described step (4) and rare earth metal salt are at least one in nitrate and chlorate.
As the preferred embodiment of the preparation method of cerium oxide zirconia base composite rare-earth oxide of the present invention, the calcining heat in described step (5) is 400 ~ 900 DEG C, and calcination time is 1 ~ 5h.Calcination atmosphere can be set as in air or oxidizing atmosphere.
As the preferred embodiment of the preparation method of cerium oxide zirconia base composite rare-earth oxide of the present invention, described method is further comprising the steps of:
(6) the cerium oxide zirconia base composite rare-earth oxide after calcining is pulverized, the described at least one pulverized in employing hammer type crushing, planetary mills pulverizing, ball milling, airflow milling.According to different purposes, one or more methods in the pulverizing of hammer type crushing, planetary mills, ball milling, airflow milling can be selected and use.
As the preferred embodiment of the preparation method of cerium oxide zirconia base composite rare-earth oxide of the present invention, the addition of described zirconates, cerium salt and rare earth metal salt contains ZrO according in gained cerium oxide zirconia base composite rare-earth oxide 2: 20 ~ 75wt%, CeO 2: the composition proportion of 15 ~ 75wt%, rare earth oxide: 1 ~ 30wt% takes.The addition of zirconates, cerium salt and rare earth metal salt in described method, contains ZrO according in gained cerium oxide zirconia base composite rare-earth oxide 2: 20 ~ 75wt%, CeO 2: the composition proportion of 15 ~ 75wt%, the stoichiometric proportion required for various oxide takes.
The invention also discloses a kind of cerium oxide zirconia base composite rare-earth oxide adopting method described above to prepare, the component containing following mass percent of described cerium oxide zirconia base composite rare-earth oxide: ZrO 2: 20 ~ 75wt%, CeO 2: 15 ~ 75wt%, rare earth oxide: 1 ~ 30wt%;
The granularity of described cerium oxide zirconia base composite rare-earth oxide is 5 ~ 20nm, wherein ZrO 2, CeO 2exist with the form of solid solution with rare earth oxide.
As the preferred embodiment of cerium oxide zirconia base composite rare-earth oxide of the present invention, described rare earth oxide is at least one in lanthanide oxide, scandium oxide and yittrium oxide.
Adopt the cerium oxide zirconia base composite rare-earth oxide that the method for the invention prepares, its total pore volume is no less than 0.55ml/g, has 10 ~ 100nm pore volume and is not less than 0.25ml/g, has 100nm ~ 10 μm pore volume not higher than 0.2ml/g; Fresh specific area>=70m 2/ g, after 1000 DEG C of heat treatment 3h, aging specific area is not less than 50m 2/ g, is not less than 20m at 1100 DEG C of heat treatment 3h or aging specific area 2/ g; Fresh oxygen storage capacity>=250 μm ol/g, aging oxygen storage capacity>=200 μm ol/g after 1000 DEG C of heat treatment 3h.
The preparation method of cerium oxide zirconia base composite rare-earth oxide of the present invention, the control of programming rate by the selection of activator solution and when adding activator, the zirconium basic sulphate salt precursor body of porosity and looseness can be formed, improve its reactivity, then by adding cerium salt and metal salt solution, add alkali reaction and generate cerium pick class rare-earth hydroxide, thus form good cerium pick solid solution, improve ageing resistance and the reproducibility of products obtained therefrom.Adopt the cerium oxide zirconia base composite rare-earth oxide that the method for the invention prepares, total pore holds large, and fresh specific area is high, has excellent reactivity, specific area Heat stability is good at high temperature, has good ageing resistace and high reducing activity.
Detailed description of the invention
For better the object, technical solutions and advantages of the present invention being described, below in conjunction with specific embodiment, the invention will be further described.
Embodiment 1
A preparation method for cerium oxide zirconia base composite rare-earth oxide, said method comprising the steps of:
(1) solubility zirconates is prepared: take certain mass zirconium oxychloride, zirconium oxychloride is water-soluble, be mixed with the zirconyl chloride solution of 25wt%;
(2) prepare activator solution: activator solution urea and sulfuric acid being hybridly prepared into 10wt%, the mass ratio of wherein said urea and the middle zirconium oxychloride of step (1) is 1:99, and the mass ratio of described sulfate radical and the middle zirconium oxychloride of step (1) is 3:5;
(3) under room temperature, the zirconyl chloride solution in step (1) is heated, slowly drip the activator solution in step (2) simultaneously, control programming rate, when activator solution is dropwised, temperature rises to 60 DEG C, then continue to heat up, be warming up to 90 DEG C from 60 DEG C in 30min, insulation 100min, form zirconium basic sulphate complex salt precursor solution;
(4) cerous nitrate solution of 20wt% and the lanthanum nitrate hexahydrate of 20wt% is prepared, and described cerous nitrate solution and lanthanum nitrate hexahydrate are added in the zirconium basic sulphate complex salt precursor solution of step (3) gained, then precipitate with the ammoniacal liquor 500g of 25wt%, obtain sediment;
(5) by step (4) gained sediment filtration washing, then calcine, calcining heat is 400 DEG C, and calcination time is 5h, cerium oxide zirconia base composite rare-earth oxide after calcining is adopted ball mill grinding, obtains the cerium oxide zirconia base composite rare-earth oxide that granularity is 20nm.
In the present embodiment, the addition of described zirconium oxychloride, cerous nitrate and lanthanum nitrate contains ZrO according in gained cerium oxide zirconia base composite rare-earth oxide 2: 20wt%, CeO 2: the composition proportion of 75wt%, lanthana: 5wt% takes.
Embodiment 2
A preparation method for cerium oxide zirconia base composite rare-earth oxide, said method comprising the steps of:
(1) solubility zirconates is prepared: take certain mass zirconyl nitrate, zirconyl nitrate is water-soluble, be mixed with the zirconyl nitrate solution of 20wt%;
(2) prepare activator solution: activator solution urea and sodium sulphate being hybridly prepared into 15wt%, the mass ratio of wherein said urea and the middle zirconyl nitrate of step (1) is 2:98, and the mass ratio of described sulfate radical and the middle zirconyl nitrate of step (1) is 1:3;
(3) under room temperature, the zirconyl nitrate solution in step (1) is heated, slowly drip the activator solution in step (2) simultaneously, control programming rate, when activator solution is dropwised, temperature rises to 60 DEG C, then continue to heat up, be warming up to 92 DEG C from 60 DEG C in 30min, insulation 60min, form zirconium basic sulphate complex salt precursor solution;
(4) 20wt% solution of cerium chloride by oxidation and 25wt% praseodymium nitrate solution is prepared, and described solution of cerium chloride by oxidation and praseodymium nitrate solution are added in the zirconium basic sulphate complex salt precursor solution of step (3) gained, then precipitate with the sodium hydroxide solution 550g of 20wt%, obtain sediment;
(5) by step (4) gained sediment filtration washing, then calcine, calcining heat is 900 DEG C, and calcination time is 1h, adopt airflow milling to pulverize the cerium oxide zirconia base composite rare-earth oxide after calcining, obtain the cerium oxide zirconia base composite rare-earth oxide that granularity is 15nm.
In the present embodiment, the addition of described zirconyl nitrate, cerium chloride and praseodymium nitrate contains ZrO according in gained cerium oxide zirconia base composite rare-earth oxide 2: 75wt%, CeO 2: the composition proportion of 15wt%, praseodymium oxide: 10wt% takes.
Embodiment 3
A preparation method for cerium oxide zirconia base composite rare-earth oxide, said method comprising the steps of:
(1) solubility zirconates is prepared: take certain mass oxalic acid zirconium, by water-soluble for oxalic acid zirconium, be mixed with the zirconium oxalate solution of 25wt%;
(2) prepare activator solution: activator solution urea and potassium sulfate being hybridly prepared into 10wt%, the mass ratio of wherein said urea and step (1) mesoxalic acid zirconium is 1.5:98.5, and the mass ratio of described sulfate radical and step (1) mesoxalic acid zirconium is 2:5;
(3) under room temperature, the zirconium oxalate solution in step (1) is heated, slowly drip the activator solution in step (2) simultaneously, control programming rate, when activator solution is dropwised, temperature rises to 60 DEG C, then continue to heat up, be warming up to 95 DEG C from 60 DEG C in 30min, insulation 20min, form zirconium basic sulphate complex salt precursor solution;
(4) 25wt% cerous nitrate and the mixed solution of cerium chloride, the scandium nitrate solution of 20wt% is prepared, and the mixed solution of described cerous nitrate and cerium chloride, scandium nitrate solution are added in the zirconium basic sulphate complex salt precursor solution of step (3) gained, then precipitate with the potassium hydroxide solution 600g of 15wt%, obtain sediment, in the mixed solution of wherein cerous nitrate and cerium chloride, the mass ratio of cerous nitrate and cerium chloride is 1:1;
(5) by step (4) gained sediment filtration washing, then calcine, calcining heat is 800 DEG C, calcination time is 4h, cerium oxide zirconia base composite rare-earth oxide after calcining is adopted ball milling and planetary mills and method pulverize, obtain the cerium oxide zirconia base composite rare-earth oxide that granularity is 5nm.
In the present embodiment, the addition of described oxalic acid zirconium, cerous nitrate, cerium chloride and scandium nitrate contains ZrO according in gained cerium oxide zirconia base composite rare-earth oxide 2: 75wt%, CeO 2: the composition proportion of 20wt%, scandium oxide: 5wt% takes.
Embodiment 4
A preparation method for cerium oxide zirconia base composite rare-earth oxide, said method comprising the steps of:
(1) prepare solubility zirconates: take certain mass zirconyl nitrate and oxalic acid zirconium, by zirconyl nitrate and oxalic acid zirconium water-soluble, be mixed with the zirconyl nitrate of 25wt% and the mixed solution of oxalic acid zirconium, wherein, the mass ratio of zirconyl nitrate and oxalic acid zirconium is 2:1;
(2) activator solution is prepared: activator solution urea and ammonium sulfate being hybridly prepared into 12wt%, the mass ratio of wherein said urea and the middle zirconyl nitrate of step (1) and oxalic acid zirconium total amount is 1:99, and the mass ratio of described sulfate radical and the middle zirconyl nitrate of step (1) and oxalic acid zirconium total amount is 1:2;
(3) under room temperature, the zirconyl nitrate in step (1) and oxalic acid zirconium mixed solution are heated, slowly drip the activator solution in step (2) simultaneously, control programming rate, when activator solution is dropwised, temperature rises to 60 DEG C, then continue to heat up, be warming up to 93 DEG C from 60 DEG C in 30min, insulation 80min, form zirconium basic sulphate complex salt precursor solution;
(4) mixed solution of 20wt% cerous nitrate solution, 25wt% lanthanum nitrate and praseodymium nitrate is prepared, and the mixed solution of described cerous nitrate solution, lanthanum nitrate and praseodymium nitrate is added in the zirconium basic sulphate complex salt precursor solution of step (3) gained, then precipitate with the NaOH 600g solution of 20wt%, obtain sediment, in the mixed solution of wherein lanthanum nitrate and praseodymium nitrate, the mass ratio of lanthanum nitrate and praseodymium nitrate is 3:1;
(5) by step (4) gained sediment filtration washing, then calcine, calcining heat is 600 DEG C, and calcination time is 3h, cerium oxide zirconia base composite rare-earth oxide after calcining is adopted hammer type crushing, obtains the cerium oxide zirconia base composite rare-earth oxide that granularity is 18nm.
In the present embodiment, the addition of described zirconyl nitrate, oxalic acid zirconium, cerous nitrate, lanthanum nitrate, praseodymium nitrate contains ZrO according in gained cerium oxide zirconia base composite rare-earth oxide 2: 30wt%, CeO 2: the composition proportion of 40wt%, lanthana and praseodymium oxide: 30wt% takes.
Embodiment 5
A preparation method for cerium oxide zirconia base composite rare-earth oxide, said method comprising the steps of:
(1) solubility zirconates is prepared: take certain mass zirconium nitrate, zirconium nitrate is water-soluble, be mixed with the zirconium nitrate solution of 25wt%;
(2) prepare activator solution: urea and potassium sulfate are hybridly prepared into 10wt% activator solution, the mass ratio of wherein said urea and the middle zirconium nitrate of step (1) is 2:98, and the mass ratio of described sulfate radical and the middle zirconium nitrate of step (1) is 9:20;
(3) under room temperature, the zirconium nitrate solution in step (1) is heated, slowly drip the activator solution in step (2) simultaneously, control programming rate, when activator solution is dropwised, temperature rises to 60 DEG C, then continue to heat up, be warming up to 95 DEG C from 60 DEG C in 30min, insulation 40min, form zirconium basic sulphate complex salt precursor solution;
(4) cerous nitrate solution of 25wt% and the yttrium nitrate solution of 20wt% is prepared, and described cerous nitrate solution and yttrium nitrate solution are added in the zirconium basic sulphate complex salt precursor solution of step (3) gained, then precipitate with 25wt% potassium hydroxide solution 500g, obtain sediment;
(5) by step (4) gained sediment filtration washing, then calcine, calcining heat is 500 DEG C, and calcination time is 2, cerium oxide zirconia base composite rare-earth oxide planetary mills after calcining is pulverized, obtains the cerium oxide zirconia base composite rare-earth oxide that granularity is 10nm.
In the present embodiment, the addition of described zirconium nitrate, cerous nitrate and yttrium nitrate contains ZrO according in gained cerium oxide zirconia base composite rare-earth oxide 2: 50wt%, CeO 2: the composition proportion of 49wt%, yittrium oxide: 1wt% takes.
Embodiment 6
The method of the invention is adopted to prepare the mensuration of the physical property of gained cerium oxide zirconia base composite rare-earth oxide
(1) total pore volume
Method of testing: be placed in drying basin at 120 DEG C of dry 2h by cerium oxide zirconia base composite rare-earth oxide to be measured and be dried to room temperature, put into pore-size distribution determinator and measure, measurement range is 0.001 ~ 10 μm.
Adopt said method to measure total pore volume of the cerium oxide zirconia base composite rare-earth oxide of embodiment 1-5 gained respectively, the results are shown in Table shown in 1.
The total pore volume result of table 1
Group Total pore volume 10 ~ 100nm pore volume 100nm ~ 10um pore volume
Embodiment 1 0.65ml/g 0.46ml/g 0.18ml/g
Embodiment 2 0.61ml/g 0.50ml/g 0.17ml/g
Embodiment 3 0.62ml/g 0.44ml/g 0.18ml/g
Embodiment 4 0.59ml/g 0.32ml/g 0.18ml/g
Embodiment 5 0.64ml/g 0.37ml/g 0.19ml/g
As seen from Table 1, total pore volume of the cerium oxide zirconia base composite rare-earth oxide of the method for the invention gained is adopted to be no less than 0.55ml/g, there is 10 ~ 100nm pore volume and be not less than 0.25ml/g, there is 100nm ~ 10 μm pore volume not higher than 0.2ml/g.
(2) specific area
Method of testing: utilize the ratio surface area instrument based on liquid nitrogen absorption method to measure.
Adopt said method to measure the specific area of the cerium oxide zirconia base composite rare-earth oxide of embodiment 1-5 gained respectively, the results are shown in Table shown in 2.
Table 2 specific area result
Group Fresh S BET(m 2/g) Aging S BET 1000℃/3hr(m 2/g) Aging S BET 1100℃/3hr(m 2/g)
Embodiment 1 76 52 21
Embodiment 2 72 50 25
Embodiment 3 75 56 22
Embodiment 4 74 55 23
Embodiment 5 75 51 20
As seen from Table 2, the fresh specific area>=70m of the cerium oxide zirconia base composite rare-earth oxide of the method for the invention gained is adopted 2/ g, aging specific area>=50m after 1000 DEG C of heat treatment 3hr 2/ g, aging specific area>=20m after 1100 DEG C of heat treatment 3hr 2/ g.
(3) oxygen storage capacity
Method of testing: measure H2-TPR according to programmed temperature method.
Get 0.3g cerium oxide zirconia base composite rare-earth oxide powder and be heated to 600 DEG C and in high purity oxygen gas, keep 60min to carry out fully oxidized.In 5%H2/Ar air-flow, with the firing rate of 10 DEG C/min, cerium oxide zirconia base composite rare-earth oxide powder is heated to 600 DEG C from 120 DEG C, the hydrogen QMS continuous measurement consumed during this period, finally from the burst size of the hydrogen consumption curve obtained and area estimation oxygen, be oxygen storage capacity OSC.
Adopt said method to measure the oxygen storage capacity of the cerium oxide zirconia base composite rare-earth oxide of embodiment 1-5 gained respectively, the results are shown in Table shown in 3.
Table 3 oxygen storage capacity result
Group Fresh OSC (μm ol/g) Aging OSC 1000℃/3hr(μmol/g)
Embodiment 1 255 225
Embodiment 2 257 219
Embodiment 3 253 220
Embodiment 4 250 217
Embodiment 5 251 200
As seen from Table 3, the fresh oxygen storage capacity >=250 μm ol/g of the cerium oxide zirconia base composite rare-earth oxide of the method for the invention gained is adopted, aging oxygen storage capacity >=200 μm ol/g after 1000 DEG C of heat treatment 3hr.
Finally to should be noted that; above embodiment is only in order to illustrate technical scheme of the present invention but not limiting the scope of the invention; although be explained in detail the present invention with reference to preferred embodiment; those of ordinary skill in the art is to be understood that; can modify to technical scheme of the present invention or equivalent replacement, and not depart from essence and the scope of technical solution of the present invention.

Claims (10)

1. a preparation method for cerium oxide zirconia base composite rare-earth oxide, is characterized in that, comprises the following steps:
(1) solubility zirconates is prepared: take certain mass zirconates, zirconates is water-soluble, be mixed with zirconium salt solution;
(2) activator solution is prepared: urea and sulfuric acid or sulfate are hybridly prepared into activator solution, the mass ratio of wherein said urea and the middle zirconates of step (1) is 1:99 ~ 2:98, and the mass ratio of described sulfate radical and the middle zirconates of step (1) is 1:3 ~ 3:5;
(3) under room temperature, the zirconium salt solution in step (1) is heated, slowly drip the activator solution in step (2) simultaneously, control programming rate, when activator solution is dropwised, temperature rises to 60 DEG C, then continue to heat up, be warming up to 90 ~ 95 DEG C from 60 DEG C in 30min, insulation 20 ~ 100min, form zirconium basic sulphate complex salt precursor solution;
(4) solubility cerium salt and rare earth metal salt is prepared, and described solubility cerium salt and rare earth metal salt are added in the zirconium basic sulphate complex salt precursor solution of step (3) gained, then precipitate with soluble hydroxide or ammonia spirit, obtain sediment;
(5) by step (4) gained sediment filtration washing, then calcine, obtain cerium oxide zirconia base composite rare-earth oxide.
2. the preparation method of cerium oxide zirconia base composite rare-earth oxide as claimed in claim 1, it is characterized in that, the zirconates in described step (1) is at least one in zirconium oxychloride, zirconyl nitrate and oxalic acid zirconium.
3. the preparation method of cerium oxide zirconia base composite rare-earth oxide as claimed in claim 1, it is characterized in that, the sulfate in described step (2) is at least one in sodium sulphate, potassium sulfate, ammonium sulfate.
4. the preparation method of cerium oxide zirconia base composite rare-earth oxide as claimed in claim 1, it is characterized in that, the solubility cerium salt in described step (4) and rare earth metal salt are at least one in nitrate and chlorate.
5. the preparation method of cerium oxide zirconia base composite rare-earth oxide as claimed in claim 1, it is characterized in that, the calcining heat in described step (5) is 400 ~ 900 DEG C, and calcination time is 1 ~ 5h.
6. the preparation method of cerium oxide zirconia base composite rare-earth oxide as claimed in claim 1, it is characterized in that, described method is further comprising the steps of:
(6) the cerium oxide zirconia base composite rare-earth oxide after calcining is pulverized, the described at least one pulverized in employing hammer type crushing, planetary mills pulverizing, ball milling, airflow milling.
7. the preparation method of cerium oxide zirconia base composite rare-earth oxide as claimed in claim 1, is characterized in that, the addition of described zirconates, cerium salt and rare earth metal salt contains ZrO according in gained cerium oxide zirconia base composite rare-earth oxide 2: 20 ~ 75wt%, CeO 2: the composition proportion of 15 ~ 75wt%, rare earth oxide: 1 ~ 30wt% takes.
8. adopt the cerium oxide zirconia base composite rare-earth oxide that method prepares as described in claim 1 or 7, it is characterized in that, the component containing following mass percent of described cerium oxide zirconia base composite rare-earth oxide: ZrO 2: 20 ~ 75wt%, CeO 2: 15 ~ 75wt%, rare earth oxide: 1 ~ 30wt%;
The granularity of described cerium oxide zirconia base composite rare-earth oxide is 5 ~ 20nm, wherein ZrO 2, CeO 2exist with the form of solid solution with rare earth oxide.
9. cerium oxide zirconia base composite rare-earth oxide as claimed in claim 8, it is characterized in that, described rare earth oxide is at least one in lanthanide oxide, scandium oxide and yittrium oxide.
10. cerium oxide zirconia base composite rare-earth oxide as claimed in claim 8, it is characterized in that, total pore volume of described cerium oxide zirconia base composite rare-earth oxide is no less than 0.55ml/g, there is 10 ~ 100nm pore volume and be not less than 0.25ml/g, there is 100nm ~ 10 μm pore volume not higher than 0.2ml/g; Fresh specific area>=70m 2/ g, after 1000 DEG C of heat treatment 3h, aging specific area is not less than 50m 2/ g, after 1100 DEG C of heat treatment 3h, aging specific area is not less than 20m 2/ g; Fresh oxygen storage capacity>=250 μm ol/g, aging oxygen storage capacity>=200 μm ol/g after 1000 DEG C of heat treatment 3h.
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Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE60033328T2 (en) * 1999-03-05 2007-11-22 Daiichi Kigenso Kagaku Kogyo Co. Ltd. Mixed oxide based on cerium and zirconium, process for its preparation; the mixed oxide containing catalyst and application of the catalyst for exhaust gas purification
CN100488623C (en) * 2005-11-10 2009-05-20 北京有色金属研究总院 Solid solution composition of cerium zirconium compound oxide with high specific surface and method for preparing the same
CN100347092C (en) * 2006-04-04 2007-11-07 欧洲海赛有限公司 Preparation method of ziroconium oxide composite nano crystal material
EP1894620B2 (en) * 2006-08-22 2023-06-07 Daiichi Kigenso Kagaku Kogyo Co., Ltd. Method to produce a porous zirconia powder
CN101058443A (en) * 2007-05-11 2007-10-24 华东理工大学 Method for preparing Ce-Zr based nano rare earth composite oxide
JP5164665B2 (en) * 2008-04-09 2013-03-21 第一稀元素化学工業株式会社 Cerium-zirconium composite oxide and method for producing the same
EP2223905A1 (en) * 2009-02-27 2010-09-01 Treibacher Industrie AG Novel zirconia ceria compositions
CN103191711B (en) * 2013-04-03 2014-08-27 潮州三环（集团）股份有限公司 Cerium oxide-zirconium oxide based composite rare-earth oxide with high specific surface area and high oxygen storage capacity and preparation method thereof

Cited By (4)

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RU2743207C2 (en) * 2015-10-27 2021-02-16 Магнезиум Электрон Лимитед Zirconium acid hydroxide
WO2018078313A1 (en) * 2016-10-27 2018-05-03 Magnesium Elektron Limited Acidic zirconium hydroxide

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