CA2020306A1 - Synthetic coarse particled iron oxide, a process for its preparation and its use - Google Patents
Synthetic coarse particled iron oxide, a process for its preparation and its useInfo
- Publication number
- CA2020306A1 CA2020306A1 CA002020306A CA2020306A CA2020306A1 CA 2020306 A1 CA2020306 A1 CA 2020306A1 CA 002020306 A CA002020306 A CA 002020306A CA 2020306 A CA2020306 A CA 2020306A CA 2020306 A1 CA2020306 A1 CA 2020306A1
- Authority
- CA
- Canada
- Prior art keywords
- iron oxide
- synthetic coarse
- feooh
- coarse particled
- iron
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G49/00—Compounds of iron
- C01G49/02—Oxides; Hydroxides
- C01G49/06—Ferric oxide [Fe2O3]
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/74—Iron group metals
- B01J23/745—Iron
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G49/00—Compounds of iron
- C01G49/02—Oxides; Hydroxides
- C01G49/08—Ferroso-ferric oxide [Fe3O4]
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K3/00—Materials not provided for elsewhere
- C09K3/14—Anti-slip materials; Abrasives
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/03—Particle morphology depicted by an image obtained by SEM
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/10—Solid density
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/12—Surface area
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Compounds Of Iron (AREA)
- Catalysts (AREA)
Abstract
SYNTHETIC COARSE PARTICLED IRON OXIDE, A PROCESS FOR ITS
PREPARATION AND ITS USE
ABSTRACT OF THE DISCLOSURE
Synthetic coarse particled iron oxide is disclosed which has an average particle size of 1 to 50 microns and a surface SBET of 1 to 5 m2/g.
Le A 26 961
PREPARATION AND ITS USE
ABSTRACT OF THE DISCLOSURE
Synthetic coarse particled iron oxide is disclosed which has an average particle size of 1 to 50 microns and a surface SBET of 1 to 5 m2/g.
Le A 26 961
Description
~Q20306 Synthetic Coarse Particled Iron Oxide, a Process forits Preparation and its Use _ This invention relates to a synthetic coarse particled iron oxide, to a process for its preparation and to is use.
Synthetic iron oxides are conventionally prepared by the aniline process, the Penniman process, the precipitation process or the roasting process ~Winnacker Kuchler, Chemische Technologie, Volume 3, Anorganische Technologie II, 9th Edition, 1983, pages 376 to 38n). The iron oxides thus obtained are generally iron oxide pigments and accordingly are finely divided. Synthetic coarse particled iron oxides suitable for use as grinding and polishing agents and as catalysts have not hitherto heen obtainable in a pure form.
Although naturally occurring iron oxides frequently fulfil the criterion of being coarse particled, they are very inhomogeneous in their composition and they contain many impurities, in particular large proportions of SiO2 and LeA 26 961 20203~6 manganese.
Coarse particled iron oxide granulates having diameters from 0 3 to 0 7 mm are known from DE-A-2 940 156 but these granulates are prepared from iron oxide colour pigments by an additional granulating step and hreak down into their individual particles under only slight mechanical stresses, e.g. when they are incorporated in lacquers or concrete.
It is an object of the present invention to provide a suitable iron oxide which is free from the above described disadvantages of the state of the art.
It has now been found that synthetic coarse particled iron oxide has an average particle size of from 1 to 50 ~m and that its sur~ace SBET is from 1 to 5 m'/g, determined by the 1 point nitrogen method. Synthetic coarse particled iron oxides according to the invention o~ining only a small amcunt of impurities are particularly suitable. Thus in a preferred embodiment, the .SiO2 content is less than 0 5%, most preferably less than ~-1%, and the manganese content is less than 0 1%. A preferred embodiment of the synthetic coarse particled iron oxide according to the invention has a tamping density of ~1 g/cm 3 .
The synthetic coarse particled iron oxide according to the invention may consist of c-FeOOH (Goethite), c-Fe2O3 (haematite), ~-Fe2O3 (maghaemite), Fe3O4 (magnetite) or a bertholoide iron oxide.
This invention also relates to a process for the preparation of synthetic coarse particled iron oxides according to the invention. It has surprisingly been possible to prepare this iron oxide according to the invention in a specific form by a single process step. For this purpose, very coarse particled iron oxide was prepared by a method analoyous to the Penniman-Zoph process (~S-A-1 327 061 and LeA 26 961 202030~
~S-A-1 368 748) in which Fe(II) is oxidized to Fe(III) and the acid released dissolves the iron scrap present to form iron(II).
In this process, it is necessary to use less than 1 g/l of ~-FeOOH as nucleus which is prepared independently from FeSO4 and sodium hydroxide solution. The smaller the quantity of nucleus, the coarser will be the particles of the iron oxide according to the invention, which is obtained as a pure phase of a-FeOOH but with a sponqy tertiary structure.
These nuclei are then built up further. The process according to the invention for the preparation of synthetic coarse particled iron oxide by the reaction of metallic iron in an acid iron salt solution with air and/or oxygen at an elevated temperature to produce a-FeO~H, optionally followed by conversion of the a-FeOOH into ~-Fe2O3, ~-Fe2O3, Fe3O4 or bertholoi~ iron oxides,is characterised in that suspensions containing less than 1 g/l of a-FeOOH as nucleus are built up until they contain from 50 to 200 g/l of FeOOH, preferably from 80 to 170 g/l of FeOOH.
If the reaction is continued to the stage of a-FeOOH, a dark hrown powder having a high tamping density and low SiO2 and manganese contents is obtained. The a-FeOOH
obtained has a spongy, tertiary structure. The surface SgET of 1 to 5 m'/g at an average particle size of 1 to 50 ~m is unexpected and characterises the spongy, porous tertiary structure of the individual particles according to the invention.
The magnification of the particles of Figure 1 in Figure 2 clearly shows that the surface consists of a large number of individual particles fused together and has a large number of pores.
Building up of the pigment into a-FeOOH could in principle also he carried out by the precipitation process in which LeA 26 961 20203n6 Fe~O4 is oxidized with oxygen and the protons formed are neutralized with sodium hydroxide solution but in view of the large amount of salt formed in this process, it is un-desirable on ecological grounds.
U-Fe2O3 may be prepared in known manner from the coarse particled ~-FeOOH obtained according to the invention. This is achieved by annealing the coarse particled ~-FeOOH at temperatures from 600 to 900C. Fe3o4 or metallic iron may ~e prepared from the ~-Fe2O3 under reducing conditions.
n Fe304 may then be further oxidized to ~-Fe2o3 or to bertholoid iron oxides (Ullmanns Enzyklopadie der technischen Chemie, 4th ~evised Edition, Volume 18, Pigmente anorganisch, pages 600 to 604 and 643 to 644).
This invention also relates to the use of the synthetic coarse particled iron oxides according to the invention as grinding and polishing materials, as catalyst raw materials and as starting materials for the preparation of coarse particled iron powders with a porous structure.
The invention is described below by way of example but is not limited to the examples given.
LeA 26 961 Example 1 Preparà~ion of nuclei: a 30% sodium hydroxide solution i~
ad~ed with stirring to an aqueous solution of iron-(II) sulphate containing 200 g/l of FeSO4 until 40% of the iron can he precipitated as iron-(II) hydroxide. Fe(II) is oxidized to Fe(III) by gassing with air at temperatures from 30 to 35C, the pH at the same time falling from 6 to 3-5.
Formation of the nucleus is then complete .
Multiplication of the nucleus by the Penniman process: a suspension containing 0 5 g/l of nucleus, calculated as FeOOH, 40 g/l of FeSO4 and 90 g/l of iron scrap is prepared.
The suspension is stirred and heated to 85C. After the required temperature has been reached, the suspension is yassed with 120 l/h of air per litre of suspension.
Multiplication of the nucleus is terminated when 130 g/l of FeOOH have been obtained. The product is filtered by the usual methods, washed until free from saltsand dried. A
brown powder is obtained.
Example 2 -This example differs from Example 1 in that the suspension is prepared with 0-1 g/l of nucleus, calculated as FeOOH, and 100 g/l of iron scrap. After 64 hours, the suspension contains 121 g/l of FeOOH, which is worked up as in Example 1 (Table 1).
Example 3 This example differs from Example 1 in that the reaction suspension is prepared without nucleus. After 96 hours, the suspension contains 155 g/l of FeOOH, which is worked up and analysed (Tahle 1).
_5_ LeA 26 961 Example 4 The product from Æxample 2 is annealed for 1 hour at 900C
in a rotary convertor. ~eddish black ~-Fe2O3 is obtained, Table 1.
Example 5 The product from Example 4 is reduced to Fe3O4 under an atmosphere of hydrogen at 450C in a rotary convertor, Table 1.
ExamPle ~S
The product from Rxample 5 is converted into ~-Fe2O3 under oxidizing conditions at 250C in a rotary convertor, Table 1.
Example 7 The product from Example 4 is reduced to pulverulent metallic iron in a reducing atmosphere at 425C in a fluidized bed.
A metal powder having an SB~T of 7-6 m~/g, a tamped density of 2 21 g/cm3 and a metal content of 99 7% ~e is obtained.
ExamPle 8 The abrasiveness of the product from Example 4 was determined by the method of S. Keifer and A. Wingen, farbe + lack 79 (1973), pages 866 to 873. It was found to be 211%, based on the trade product of ~ayer AG, Bayertitan~ ~-FD-I.
keA 26 961 Ta~le 1 Product from SB~T Average Tamped SiO2Mn Particle Density**
niameter*
(m~/g) (~m) (g/cm3) % %
1st ~xample 3 1 10 1 1 57 0-0200-009 2nd Example 2-6 19-2 2 18 0-0180 014 3rd Example 1 6 25-1 2-21 0-0230-012 4th Example 1-3 18-7 2-42 0-0250-017 5th ~xample 2-2 16-1 2-34 0-0280-015 6th Example 1 8 13 7 2-25 0-0240-019 * according to particle Size Anaylsis, H.~,.Barth, Shao-Thang Sunj ~.M. Nickel; Anal. Chem. 1987, 59, 142 R to 162 ~
** according to DIN 53 194 (ISO DIN 787).
LeA 26 961
Synthetic iron oxides are conventionally prepared by the aniline process, the Penniman process, the precipitation process or the roasting process ~Winnacker Kuchler, Chemische Technologie, Volume 3, Anorganische Technologie II, 9th Edition, 1983, pages 376 to 38n). The iron oxides thus obtained are generally iron oxide pigments and accordingly are finely divided. Synthetic coarse particled iron oxides suitable for use as grinding and polishing agents and as catalysts have not hitherto heen obtainable in a pure form.
Although naturally occurring iron oxides frequently fulfil the criterion of being coarse particled, they are very inhomogeneous in their composition and they contain many impurities, in particular large proportions of SiO2 and LeA 26 961 20203~6 manganese.
Coarse particled iron oxide granulates having diameters from 0 3 to 0 7 mm are known from DE-A-2 940 156 but these granulates are prepared from iron oxide colour pigments by an additional granulating step and hreak down into their individual particles under only slight mechanical stresses, e.g. when they are incorporated in lacquers or concrete.
It is an object of the present invention to provide a suitable iron oxide which is free from the above described disadvantages of the state of the art.
It has now been found that synthetic coarse particled iron oxide has an average particle size of from 1 to 50 ~m and that its sur~ace SBET is from 1 to 5 m'/g, determined by the 1 point nitrogen method. Synthetic coarse particled iron oxides according to the invention o~ining only a small amcunt of impurities are particularly suitable. Thus in a preferred embodiment, the .SiO2 content is less than 0 5%, most preferably less than ~-1%, and the manganese content is less than 0 1%. A preferred embodiment of the synthetic coarse particled iron oxide according to the invention has a tamping density of ~1 g/cm 3 .
The synthetic coarse particled iron oxide according to the invention may consist of c-FeOOH (Goethite), c-Fe2O3 (haematite), ~-Fe2O3 (maghaemite), Fe3O4 (magnetite) or a bertholoide iron oxide.
This invention also relates to a process for the preparation of synthetic coarse particled iron oxides according to the invention. It has surprisingly been possible to prepare this iron oxide according to the invention in a specific form by a single process step. For this purpose, very coarse particled iron oxide was prepared by a method analoyous to the Penniman-Zoph process (~S-A-1 327 061 and LeA 26 961 202030~
~S-A-1 368 748) in which Fe(II) is oxidized to Fe(III) and the acid released dissolves the iron scrap present to form iron(II).
In this process, it is necessary to use less than 1 g/l of ~-FeOOH as nucleus which is prepared independently from FeSO4 and sodium hydroxide solution. The smaller the quantity of nucleus, the coarser will be the particles of the iron oxide according to the invention, which is obtained as a pure phase of a-FeOOH but with a sponqy tertiary structure.
These nuclei are then built up further. The process according to the invention for the preparation of synthetic coarse particled iron oxide by the reaction of metallic iron in an acid iron salt solution with air and/or oxygen at an elevated temperature to produce a-FeO~H, optionally followed by conversion of the a-FeOOH into ~-Fe2O3, ~-Fe2O3, Fe3O4 or bertholoi~ iron oxides,is characterised in that suspensions containing less than 1 g/l of a-FeOOH as nucleus are built up until they contain from 50 to 200 g/l of FeOOH, preferably from 80 to 170 g/l of FeOOH.
If the reaction is continued to the stage of a-FeOOH, a dark hrown powder having a high tamping density and low SiO2 and manganese contents is obtained. The a-FeOOH
obtained has a spongy, tertiary structure. The surface SgET of 1 to 5 m'/g at an average particle size of 1 to 50 ~m is unexpected and characterises the spongy, porous tertiary structure of the individual particles according to the invention.
The magnification of the particles of Figure 1 in Figure 2 clearly shows that the surface consists of a large number of individual particles fused together and has a large number of pores.
Building up of the pigment into a-FeOOH could in principle also he carried out by the precipitation process in which LeA 26 961 20203n6 Fe~O4 is oxidized with oxygen and the protons formed are neutralized with sodium hydroxide solution but in view of the large amount of salt formed in this process, it is un-desirable on ecological grounds.
U-Fe2O3 may be prepared in known manner from the coarse particled ~-FeOOH obtained according to the invention. This is achieved by annealing the coarse particled ~-FeOOH at temperatures from 600 to 900C. Fe3o4 or metallic iron may ~e prepared from the ~-Fe2O3 under reducing conditions.
n Fe304 may then be further oxidized to ~-Fe2o3 or to bertholoid iron oxides (Ullmanns Enzyklopadie der technischen Chemie, 4th ~evised Edition, Volume 18, Pigmente anorganisch, pages 600 to 604 and 643 to 644).
This invention also relates to the use of the synthetic coarse particled iron oxides according to the invention as grinding and polishing materials, as catalyst raw materials and as starting materials for the preparation of coarse particled iron powders with a porous structure.
The invention is described below by way of example but is not limited to the examples given.
LeA 26 961 Example 1 Preparà~ion of nuclei: a 30% sodium hydroxide solution i~
ad~ed with stirring to an aqueous solution of iron-(II) sulphate containing 200 g/l of FeSO4 until 40% of the iron can he precipitated as iron-(II) hydroxide. Fe(II) is oxidized to Fe(III) by gassing with air at temperatures from 30 to 35C, the pH at the same time falling from 6 to 3-5.
Formation of the nucleus is then complete .
Multiplication of the nucleus by the Penniman process: a suspension containing 0 5 g/l of nucleus, calculated as FeOOH, 40 g/l of FeSO4 and 90 g/l of iron scrap is prepared.
The suspension is stirred and heated to 85C. After the required temperature has been reached, the suspension is yassed with 120 l/h of air per litre of suspension.
Multiplication of the nucleus is terminated when 130 g/l of FeOOH have been obtained. The product is filtered by the usual methods, washed until free from saltsand dried. A
brown powder is obtained.
Example 2 -This example differs from Example 1 in that the suspension is prepared with 0-1 g/l of nucleus, calculated as FeOOH, and 100 g/l of iron scrap. After 64 hours, the suspension contains 121 g/l of FeOOH, which is worked up as in Example 1 (Table 1).
Example 3 This example differs from Example 1 in that the reaction suspension is prepared without nucleus. After 96 hours, the suspension contains 155 g/l of FeOOH, which is worked up and analysed (Tahle 1).
_5_ LeA 26 961 Example 4 The product from Æxample 2 is annealed for 1 hour at 900C
in a rotary convertor. ~eddish black ~-Fe2O3 is obtained, Table 1.
Example 5 The product from Example 4 is reduced to Fe3O4 under an atmosphere of hydrogen at 450C in a rotary convertor, Table 1.
ExamPle ~S
The product from Rxample 5 is converted into ~-Fe2O3 under oxidizing conditions at 250C in a rotary convertor, Table 1.
Example 7 The product from Example 4 is reduced to pulverulent metallic iron in a reducing atmosphere at 425C in a fluidized bed.
A metal powder having an SB~T of 7-6 m~/g, a tamped density of 2 21 g/cm3 and a metal content of 99 7% ~e is obtained.
ExamPle 8 The abrasiveness of the product from Example 4 was determined by the method of S. Keifer and A. Wingen, farbe + lack 79 (1973), pages 866 to 873. It was found to be 211%, based on the trade product of ~ayer AG, Bayertitan~ ~-FD-I.
keA 26 961 Ta~le 1 Product from SB~T Average Tamped SiO2Mn Particle Density**
niameter*
(m~/g) (~m) (g/cm3) % %
1st ~xample 3 1 10 1 1 57 0-0200-009 2nd Example 2-6 19-2 2 18 0-0180 014 3rd Example 1 6 25-1 2-21 0-0230-012 4th Example 1-3 18-7 2-42 0-0250-017 5th ~xample 2-2 16-1 2-34 0-0280-015 6th Example 1 8 13 7 2-25 0-0240-019 * according to particle Size Anaylsis, H.~,.Barth, Shao-Thang Sunj ~.M. Nickel; Anal. Chem. 1987, 59, 142 R to 162 ~
** according to DIN 53 194 (ISO DIN 787).
LeA 26 961
Claims (15)
1. Synthetic coarse particled iron oxide having an average particle size of 1 to 50 microns and a surface SBET between 1 and 5 m2/g.
2. Synthetic coarse particled iron oxide as claimed in Claim 1 having an SiO2 content of <0.5% and a manganese content of <0.1%.
3. Synthetic coarse particled iron oxide as claimed in claim 2 wherein the SiO2 content is <0.1%.
4. Synthetic coarse particled iron oxide as claimed in Claim 1 wherein the tamped density is >lg/cm3.
5. Synthetic coarse particled iron oxide as claimed in Claim 1 wherein the iron oxide is .alpha.-FeOOH.
6. Synthetic coarse particled iron oxide as claimed in Claim 1 wherein the iron oxide is .alpha.-Fe2O3.
7. Synthetic coarse particled iron oxide as claimed in Claim 1 wherein the iron oxide is ?-Fe2O3.
8. Synthetic coarse particled iron oxide as claimed in Claim 1 wherein the iron oxide is Fe3O4.
9. Synthetic coarse particled iron oxide as claimed in Claim 1 wherein the iron oxide is a bertholoid iron oxide.
Le A 26 961 - 8 -
Le A 26 961 - 8 -
10. A process for the preparation of synthetic coarse particled iron oxide comprising reacting metallic iron in an acid iron salt solution with air or oxygen at an elevated temperature to form .alpha.-FeOOH
wherein suspensions containing less than 1 g/l of .alpha.-FeOOH as nucleus are built up to an FeOOH content of from 50 to 200 g/l.
wherein suspensions containing less than 1 g/l of .alpha.-FeOOH as nucleus are built up to an FeOOH content of from 50 to 200 g/l.
11. The process of claim 10 further comprising con-verting the .alpha.-FeOOH to .alpha.-Fe2O2, ?-Fe2O3, Fe3O4 or bertholoid iron oxide
12. The process of claim 10 wherein the suspensions are built up to an FeOOH content of from 80 to 170 g/l.
13. Synthetic coarse particled iron oxides prepared by the method of claim 10
14. Synthetic coarse particled iron oxides prepared by the method of claim 11
15. Grinding materials containing the synthetic coarse particled iron oxides of claim 1 Le A 26 961 - 9 -
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP3922106.7 | 1989-07-05 | ||
| DE3922106A DE3922106A1 (en) | 1989-07-05 | 1989-07-05 | SYNTHETIC LARGE-PARTIC IRON OXIDE, METHOD FOR THE PRODUCTION AND USE THEREOF |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2020306A1 true CA2020306A1 (en) | 1991-01-06 |
Family
ID=6384359
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002020306A Abandoned CA2020306A1 (en) | 1989-07-05 | 1990-07-03 | Synthetic coarse particled iron oxide, a process for its preparation and its use |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0406633B2 (en) |
| JP (1) | JP2654238B2 (en) |
| AU (1) | AU633110B2 (en) |
| CA (1) | CA2020306A1 (en) |
| DE (2) | DE3922106A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6863877B2 (en) | 2000-07-31 | 2005-03-08 | Basf Aktiengesellschaft | Iron oxides of reduced chloride content |
| EP3553149B1 (en) | 2016-12-12 | 2024-01-31 | Powdertech Co., Ltd. | Iron oxide powder for brake friction material |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3918894A1 (en) * | 1989-06-09 | 1990-12-13 | Bayer Ag | METHOD FOR PRODUCING IRON OXIDE YELLOW PIGMENTS |
| AU696088B2 (en) * | 1994-12-14 | 1998-09-03 | Shell Internationale Research Maatschappij B.V. | Large particle dehydrogenation catalyst and process |
| DE10044398A1 (en) | 2000-09-08 | 2002-03-21 | Bayer Ag | Production of iron oxide yellow pigment, used in building material, plastics, paper, color or for producing heterogeneous catalyst e.g. for ethylbenzene dehydrogenation, comprises seeding pre-precipitated iron-II chloride and oxidation |
| DK1512726T3 (en) | 2003-09-03 | 2016-01-18 | Lanxess Deutschland Gmbh | PROCEDURE FOR THE MANUFACTURE OF IRON OXID YELLOW PIGMENTS WITH CACO3 AS A PREPARING AGENT |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1094900A (en) * | 1966-10-12 | 1967-12-13 | Elektrochemisches Kombinat Bitterfeld Veb | Process for the production of iron-ó¾-oxide |
| US4221766A (en) | 1976-12-10 | 1980-09-09 | Cities Service Company | Minimizing soluble iron concentration in a plant effluent |
| US4201761A (en) * | 1977-06-02 | 1980-05-06 | Suntech, Inc. | Process for making iron oxide of controlled particle size |
| WO1982002346A1 (en) * | 1980-12-30 | 1982-07-22 | Sweetener Inc Gas | Scavenging hydrogen sulfide from hydrocarbon gases |
| US4459276A (en) * | 1981-09-17 | 1984-07-10 | Agency Of Industrial Science & Technology | Yellow iron oxide pigment and method for manufacture thereof |
| JPS6038487A (en) * | 1983-08-11 | 1985-02-28 | Nisshinbo Ind Inc | Friction material |
| JP2727187B2 (en) * | 1987-09-30 | 1998-03-11 | 戸田工業株式会社 | Method for producing plate-like hematite particle powder |
| JP2704521B2 (en) * | 1988-04-08 | 1998-01-26 | 戸田工業株式会社 | Plate-like magnetite particle powder and production method thereof |
| DE3821342A1 (en) * | 1988-06-24 | 1989-12-28 | Bayer Ag | NEW IRON OXIDE PIGMENTS, METHOD FOR THE PRODUCTION AND USE THEREOF |
| DE3918894A1 (en) * | 1989-06-09 | 1990-12-13 | Bayer Ag | METHOD FOR PRODUCING IRON OXIDE YELLOW PIGMENTS |
-
1989
- 1989-07-05 DE DE3922106A patent/DE3922106A1/en not_active Withdrawn
-
1990
- 1990-06-22 DE DE59009526T patent/DE59009526D1/en not_active Expired - Fee Related
- 1990-06-22 EP EP90111806A patent/EP0406633B2/en not_active Expired - Lifetime
- 1990-06-29 AU AU58027/90A patent/AU633110B2/en not_active Ceased
- 1990-07-02 JP JP2172829A patent/JP2654238B2/en not_active Expired - Fee Related
- 1990-07-03 CA CA002020306A patent/CA2020306A1/en not_active Abandoned
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6863877B2 (en) | 2000-07-31 | 2005-03-08 | Basf Aktiengesellschaft | Iron oxides of reduced chloride content |
| EP3553149B1 (en) | 2016-12-12 | 2024-01-31 | Powdertech Co., Ltd. | Iron oxide powder for brake friction material |
Also Published As
| Publication number | Publication date |
|---|---|
| DE3922106A1 (en) | 1991-01-17 |
| JP2654238B2 (en) | 1997-09-17 |
| JPH03137023A (en) | 1991-06-11 |
| AU633110B2 (en) | 1993-01-21 |
| AU5802790A (en) | 1991-01-10 |
| DE59009526D1 (en) | 1995-09-21 |
| EP0406633B1 (en) | 1995-08-16 |
| EP0406633A2 (en) | 1991-01-09 |
| EP0406633B2 (en) | 1998-11-11 |
| EP0406633A3 (en) | 1991-12-18 |
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