CN1557773A - Ion-exchange process for preparation of super-thin sheet-shaped M-type barium ferrite particulates - Google Patents
Ion-exchange process for preparation of super-thin sheet-shaped M-type barium ferrite particulates Download PDFInfo
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- CN1557773A CN1557773A CNA2004100139595A CN200410013959A CN1557773A CN 1557773 A CN1557773 A CN 1557773A CN A2004100139595 A CNA2004100139595 A CN A2004100139595A CN 200410013959 A CN200410013959 A CN 200410013959A CN 1557773 A CN1557773 A CN 1557773A
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- ion
- exchange
- resin
- barium ferrite
- thin sheet
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- AJCDFVKYMIUXCR-UHFFFAOYSA-N oxobarium;oxo(oxoferriooxy)iron Chemical compound [Ba]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O AJCDFVKYMIUXCR-UHFFFAOYSA-N 0.000 title claims abstract description 23
- 238000005342 ion exchange Methods 0.000 title claims description 3
- 238000002360 preparation method Methods 0.000 title description 12
- 238000000034 method Methods 0.000 claims abstract description 22
- 150000002500 ions Chemical class 0.000 claims abstract description 19
- 239000003456 ion exchange resin Substances 0.000 claims abstract description 17
- 229920003303 ion-exchange polymer Polymers 0.000 claims abstract description 17
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000011347 resin Substances 0.000 claims abstract description 16
- 229920005989 resin Polymers 0.000 claims abstract description 16
- 229910052788 barium Inorganic materials 0.000 claims abstract description 8
- NMCUIPGRVMDVDB-UHFFFAOYSA-L iron dichloride Chemical compound Cl[Fe]Cl NMCUIPGRVMDVDB-UHFFFAOYSA-L 0.000 claims abstract description 7
- -1 barium halide Chemical class 0.000 claims abstract description 5
- 235000003891 ferrous sulphate Nutrition 0.000 claims abstract description 5
- 239000011790 ferrous sulphate Substances 0.000 claims abstract description 5
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 claims abstract description 5
- 229910000359 iron(II) sulfate Inorganic materials 0.000 claims abstract description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 25
- 238000010438 heat treatment Methods 0.000 claims description 8
- 239000002994 raw material Substances 0.000 claims description 7
- 230000003252 repetitive effect Effects 0.000 claims description 6
- 238000005201 scrubbing Methods 0.000 claims description 6
- 238000001179 sorption measurement Methods 0.000 claims description 6
- 238000000354 decomposition reaction Methods 0.000 claims description 3
- 238000007669 thermal treatment Methods 0.000 claims description 2
- 239000000463 material Substances 0.000 abstract description 11
- 230000005415 magnetization Effects 0.000 abstract description 10
- 239000002245 particle Substances 0.000 abstract description 10
- 229910001422 barium ion Inorganic materials 0.000 abstract description 2
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 abstract 1
- 229960002089 ferrous chloride Drugs 0.000 abstract 1
- 229910001448 ferrous ion Inorganic materials 0.000 abstract 1
- 229920006395 saturated elastomer Polymers 0.000 abstract 1
- 238000005406 washing Methods 0.000 abstract 1
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 5
- 229910052742 iron Inorganic materials 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- WDIHJSXYQDMJHN-UHFFFAOYSA-L barium chloride Chemical compound [Cl-].[Cl-].[Ba+2] WDIHJSXYQDMJHN-UHFFFAOYSA-L 0.000 description 4
- 229940045511 barium chloride Drugs 0.000 description 4
- 229910001626 barium chloride Inorganic materials 0.000 description 4
- 238000000975 co-precipitation Methods 0.000 description 4
- 238000001816 cooling Methods 0.000 description 4
- 239000012153 distilled water Substances 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 238000010792 warming Methods 0.000 description 4
- 239000000443 aerosol Substances 0.000 description 2
- 229910021529 ammonia Inorganic materials 0.000 description 2
- NKQIMNKPSDEDMO-UHFFFAOYSA-L barium bromide Chemical compound [Br-].[Br-].[Ba+2] NKQIMNKPSDEDMO-UHFFFAOYSA-L 0.000 description 2
- 229910001620 barium bromide Inorganic materials 0.000 description 2
- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 description 2
- 238000000593 microemulsion method Methods 0.000 description 2
- 238000003746 solid phase reaction Methods 0.000 description 2
- 238000010671 solid-state reaction Methods 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000001308 synthesis method Methods 0.000 description 2
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 239000003963 antioxidant agent Substances 0.000 description 1
- 230000003078 antioxidant effect Effects 0.000 description 1
- 235000006708 antioxidants Nutrition 0.000 description 1
- QVQLCTNNEUAWMS-UHFFFAOYSA-N barium oxide Chemical compound [Ba]=O QVQLCTNNEUAWMS-UHFFFAOYSA-N 0.000 description 1
- 229910001864 baryta Inorganic materials 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- MVFCKEFYUDZOCX-UHFFFAOYSA-N iron(2+);dinitrate Chemical compound [Fe+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O MVFCKEFYUDZOCX-UHFFFAOYSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 238000003980 solgel method Methods 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
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- Hard Magnetic Materials (AREA)
- Compounds Of Iron (AREA)
Abstract
The ion exchange resin process for preparing superthin M-type barium ferrite particle uses ferrous chloride or ferrous sulfate, barium halide and H+ type ion exchange resin as material, with the material having Ba/Fe ratio of 1 to 11.5-12; and includes exchanging Ba ion and ferrous ion onto ion exchange resin, and repeated washing the resin to eliminate excessive physically adsorbed ion, high temperature roasting of exchanged resin at 700-1100 deg.c for 1-10 hr. The barium ferrite particle prepared in the method of the present invention has saturated magnetization intensity up to 71 sq Am/kg near the theoretic value and moderate coercive force.
Description
One, technical field
The present invention relates to ion-exchange-resin process and prepare high saturation and magnetic intensity, the moderate super-thin sheet-shaped barium ferrite particulate of coercive force.
Two, prior art
M-type barium ferrite (BaFe
12O
19) belong to hexaplanar, obtained using very widely as permanent magnet material, ultra-high frequency magneticsubstance, microwave and millimeter wave material.Because it has monadic magnetocrystalline anisotropy, easy magnetizing axis is perpendicular to the plane of particle, and has extraordinary anticorrosive, anti-oxidant and abrasion resistance properties, is ideal high-density perpendicular magnetic recording material therefore.For the coercive force of regulating barium ferrite to satisfy the needs of different field, adopt the method for ionic replacement to reduce coercive force usually.As using (Co
2++ Ti
4+), (Co
2++ Sn
4+), (Mn
2++ Ti
4+), (Zn
2++ Ti
4+) wait part to replace Fe
3+, can reduce the coercive force of barium ferrite significantly, the saturation magnetization that replaces the back product is generally at 50-60Am
2/ kg.Preparation polycrystalline M-type barium ferrite (BaFe
12O
19), the past is adopted solid state reaction (china-clay method) mostly, and it is a kind of preparation method who is generated new sosoloid by ion that participates in reaction or atom through thermodiffusion, usually need very high maturing temperature, the product easy-sintering is easily reunited between particle, product particle is bigger, is generally more than tens microns.In order to obtain tiny, the homogeneous of particle diameter, high performance barium ferrite particulate, people have taked a lot of preparation methods, as chemical coprecipitation, micro emulsion method, aerosol synthesis method and cryochem process etc.These methods are compared with traditional in the past solid state reaction (china-clay method), maximum characteristics are that preparation process all is that raw material begins with solution, because barium, iron two components all exist with ionic species in the solution, can reach the mixing of atomic level, the blended homogeneity is the highest.But in entire reaction course, keep this homogeneity very difficult from start to finish.As chemical coprecipitation, be difficult to barium, iron two components are synchronously fully precipitated, most cases is that barium ion is adsorbed among the throw out of iron; The micro emulsion method can be regarded the chemical coprecipitation reaction of being carried out as in numerous nano level microreactor, it can prepare the superfine throw out, but can't guarantee each component ionic homogeneity of granule interior; In aerosol synthesis method and cryochem process,, cause the ununiformity of forming because the difference of nitrate of baryta and iron nitrate solubleness in water is difficult to avoid separating out in advance of barium component.Ion-exchange-resin process of the present invention then can keep high homogeneity, the dispersiveness between each component in the entire reaction course that ferrite generates, the sample that makes has high shape anisotropy, be laminar, having high saturation magnetization, moderate coercive force, is the Perfected process of preparation magnetic recording with the barium ferrite particulate.
Three, summary of the invention
The objective of the invention is to seek a kind of novel method--ion-exchange-resin process for preparing high-performance, can be used for the M-type barium ferrite particulate of magnetic recording media, key step is: containing Ba
2+Ion and Fe
2+In the ionic mixing solutions, utilize H
+Required Ba is gone up in the exchange of type ion exchange resin
2+Ion and Fe
2+Ion, make and respectively form in the three-dimensional net structure that ion is evenly dispersed in this ion exchange resin, and remain in solution in entire reaction course intermediate ion dispersed uniform, therefore can under very low maturing temperature, generate single barium ferrite thing phase in liquid state.The characteristics of this method are: raw material is mixed very even, the segregation that can not produce component, and composition is easy to control.
Technical scheme of the present invention is with iron protochloride or ferrous sulfate, barium halide, H
+Type ion exchange resin is raw material, earlier with Ba
2+Ion and Fe
2+Ion-exchange is to ion exchange resin, and repetitive scrubbing is removed the unnecessary ion of physical adsorption, adopts first pre-burning to decompose two step heat treating process of high-temperature roasting again, and thermal treatment temp is 700-1100 ℃, heat treatment time 1-10 hour.The injected volume of raw material: (mol ratio) Ba/Fe=1: 11.5～1: 12, (Ba
2++ Fe
2+) ion total yield sum is the normal 40-80% of resin maximum exchange.The barium ferrite product that adopts method of the present invention to prepare is the hexagonal flaky texture of perfect crystalline, thickness is less than 30 nanometers, particle diameter has very high shape anisotropy less than 300 nanometers, and the diameter thickness ratio is up to 13 (Renminbi coins that suitable face amount is 1 yuan).
Also can adopt first pre-burning to decompose two step heat treating process of high-temperature roasting again, the decomposition heat treatment temp of pre-burning is 550-650 ℃, heat treatment time 1-5 hour.
Adopt the barium ferrite particle of method preparation of the present invention, saturation magnetization is up to 71Am
2/ kg, near theoretical expected value, and the coercive force of product is moderate, for about 300kA/m (3800Oe), than the sample of the close particle diameter that adopts the preparation of sol-gel method and chemical coprecipitation low about 160kA/m (2000Oe).
Product with the present invention preparation carries out structure and performance characterization by following means: the thing that the D/Max-RA rotating anode X-ray diffractometer (XRD) that adopts Japanese Rigaku company to produce is determined magnetic nanometer particles mutually; Utilize the shape and size of JEM-200 CX transmission electron microscope (TEM) the direct viewing product that Japanese JEOL company produces; The magnetic property of product adopts U.S. Lakeshore vibrating sample magnetometer (VSM) to measure.
Four, description of drawings
Fig. 1 is the XRD spectra of the product of embodiment 3 preparations.
Fig. 2 is the TEM photo of the product of embodiment 3 preparations.
Fig. 3 is the magnetic measurement results of the product of embodiment 4 preparations.
Five, embodiment
Below be embodiments of the invention (agents useful for same is a chemical pure among the embodiment).
Embodiment 1:
Step 1: quantitative iron protochloride, barium bromide are dissolved in (material molar ratio: Ba/Fe=1: 12), get clear solution in the aquae destillata.
Step 2: a certain amount of E.Merck IV weak-type ion exchange resin (exchange group is-COOH pH scope of application 6-14) is joined in the above-mentioned mixing solutions that contains barium, iron ion (Ba
2++ Fe
2+) ion total yield sum is that the resin maximum exchange is normal 70%, guaranteeing exchange fully, 60 ℃ of constant temperature constantly stir and make exchange more abundant.Slowly dripping weak ammonia in exchange process maintains near the neutrality pH value of solution value.
Step 3: the resin that finishes with distilled water repetitive scrubbing exchange is to remove the unnecessary ion of physical adsorption, 110 ℃ of dried resins are placed retort furnace, speed with 4.5 ℃/min is warming up to 1000 ℃, be incubated 5 hours, furnace cooling obtains average grain size 245 nanometers, mean thickness 20 nanometers, diameter thickness is than the pure barium ferrite particulate that is 12, saturation magnetization 68.2Am
2/ kg, coercive force 295kA/m (3710Oe).
Embodiment 2:
Step 1: quantitative iron protochloride, bariumchloride are dissolved in (material molar ratio: Ba/Fe=1: 11.8), get clear solution in the aquae destillata.
Step 2: a certain amount of E.Merck IV weak-type ion exchange resin is joined in the above-mentioned mixing solutions that contains barium, iron ion (Ba
2++ Fe
2+) ion total yield sum is that the resin maximum exchange is normal 80%, guaranteeing exchange fully, 60 ℃ of constant temperature constantly stir and make exchange more abundant.Slowly dripping weak ammonia in exchange process maintains near the neutrality pH value of solution value.
Step 3: the resin that finishes with distilled water repetitive scrubbing exchange is to remove the unnecessary ion of physical adsorption, 110 ℃ of dried resins are placed retort furnace, speed with 4.5 ℃/min is warming up to 900 ℃, be incubated 5 hours, furnace cooling obtains average grain size 238 nanometers, mean thickness 19 nanometers, diameter thickness is than the pure barium ferrite particulate that is 12.5, saturation magnetization 69.1Am
2/ kg, coercive force 300kA/m (3780Oe).
Under the identical situation of other condition, be incubated 2 hours and do not have obviously difference in 8 hours.
Embodiment 3:
Step 1: quantitative iron protochloride, bariumchloride are dissolved in (material molar ratio: Ba/Fe=1: 11.6), get clear solution in the aquae destillata.
Step 2: with step 2 among the embodiment 2.
Step 3: the resin that finishes with distilled water repetitive scrubbing exchange is to remove the unnecessary ion of physical adsorption, 110 ℃ of dried resins are placed retort furnace, speed with 4.5 ℃/min is warming up to 850 ℃, be incubated 5 hours, furnace cooling obtains average grain size 220 nanometers, mean thickness 17 nanometers, diameter thickness is than the pure barium ferrite particulate that is 13, saturation magnetization 71.0Am
2/ kg, coercive force 300kA/m (3800Oe).
Embodiment 4:
Step 1: quantitative iron protochloride, bariumchloride are dissolved in (material molar ratio: Ba/Fe=1: 11.6), get clear solution in the aquae destillata.
Step 2: with step 2 among the embodiment 2.
Step 3: the resin that finishes with distilled water repetitive scrubbing exchange is to remove the unnecessary ion of physical adsorption, 110 ℃ of dried resins are placed retort furnace, speed with 4.5 ℃/min is warming up to 950 ℃, be incubated 5 hours, furnace cooling obtains average grain size 255 nanometers, mean thickness 23 nanometers, diameter thickness is than the pure barium ferrite particulate that is 11, saturation magnetization 70.5Am
2/ kg, coercive force 291kA/m (3650Oe).
Embodiment 5
Quantitatively ferrous sulfate, bariumchloride are dissolved in that (material molar ratio: Ba/Fe=1: 11.5), other condition is with embodiment 2 in the aquae destillata.Obtain average grain size 280 nanometers, mean thickness 30 nanometers, diameter thickness is than the pure barium ferrite particulate that is 9, saturation magnetization 70Am
2/ kg, coercive force 298kA/m (3700Oe).
Embodiment 6
Quantitatively ferrous sulfate, barium bromide are dissolved in that (material molar ratio: Ba/Fe=1: 12) other condition is with embodiment 3 in the aquae destillata.Obtain average grain size 250 nanometers, mean thickness 23 nanometers, diameter thickness is than the pure barium ferrite particulate that is 11, saturation magnetization 70.5Am
2/ kg, coercive force 291kA/m (3650Oe).
Embodiment 7
Above-mentioned raw materials prescription: adopt first pre-burning to decompose two step heat treating process of high-temperature roasting again, the decomposition heat treatment temp of pre-burning is 550-650 ℃, heat treatment time be 1,3 or 5 hour all can, performance is more stable, the yield rate height.
Claims (2)
1, ion-exchange-resin process prepares super-thin sheet-shaped M-type barium ferrite particulate, it is characterized in that with iron protochloride or ferrous sulfate, barium halide, H
+Type ion exchange resin is raw material, earlier with Ba
2+Ion and Fe
2+Ion-exchange is to ion exchange resin, and the resin after the repetitive scrubbing exchange is removed the unnecessary ion of physical adsorption, the injected volume of raw material: (mol ratio) Ba/Fe=1: 11.5 ~ 1: 12, and (Ba
2++ Fe
2+) ion total yield sum is the normal 40-80% of resin maximum exchange; Resin after the exchange is handled through high-temperature roasting, and thermal treatment temp is 700-1100 ℃, heat treatment time 1-10 hour.
2, prepare super-thin sheet-shaped M-type barium ferrite particulate by the described ion-exchange-resin process of claim 1, it is characterized in that adopting first pre-burning to decompose two step heat treating process of high-temperature roasting again, the decomposition heat treatment temp of pre-burning is 550-650 ℃, heat treatment time 1-5 hour.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100139595A CN100484899C (en) | 2004-01-19 | 2004-01-19 | Ion-exchange process for preparation of super-thin sheet-shaped M-type barium ferrite particulates |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100139595A CN100484899C (en) | 2004-01-19 | 2004-01-19 | Ion-exchange process for preparation of super-thin sheet-shaped M-type barium ferrite particulates |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1557773A true CN1557773A (en) | 2004-12-29 |
| CN100484899C CN100484899C (en) | 2009-05-06 |
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|---|---|---|---|
| CNB2004100139595A Expired - Fee Related CN100484899C (en) | 2004-01-19 | 2004-01-19 | Ion-exchange process for preparation of super-thin sheet-shaped M-type barium ferrite particulates |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101830691A (en) * | 2009-03-13 | 2010-09-15 | 中国科学院福建物质结构研究所 | Method for synthesizing nano ferrite soft magnetic material |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1353744A1 (en) * | 1985-06-26 | 1987-11-23 | Всесоюзный Проектно-Технологический Институт По Электробытовым Машинам И Приборам | Apparatus for ion-exchange cleaning of waste water |
| CN1066564C (en) * | 1997-06-14 | 2001-05-30 | 中国科学院山西煤炭化学研究所 | Method for preparing super fine barium ferrite powder |
| CN1179911C (en) * | 2003-04-30 | 2004-12-15 | 武汉众兴磁业技术开发有限公司 | Productive method of sintering anisotropic permanent magnetic ferrite |
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2004
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101830691A (en) * | 2009-03-13 | 2010-09-15 | 中国科学院福建物质结构研究所 | Method for synthesizing nano ferrite soft magnetic material |
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