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公开(公告)号：DE2805405A1
公开(公告)日：1979-08-16
申请号：DE2805405
申请日：1978-02-09
Applicant: BASF AG
Inventor： AUTZEN HORST DIPL CHEM DR , MOTZ HERBERT DIPL ING DR , RUDOLF PETER DIPL CHEM DR , SARNECKI WILHELM DIPL CHEM DR , STECK WERNER DIPL CHEM DR , VAETH GUENTER
Abstract: A process for the manufacture of acicular ferrimagnetic iron oxide by converting acicular iron(III) oxide hydroxide at from 300 DEG to 650 DEG C., by treatment with an organic compound which decomposes in this temperature range in the presence of iron oxide, the iron(III) oxide hydroxide used for the reaction being a lepidocrocite which has been heat-treated at from 300 DEG to 700 DEG C.
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公开(公告)号：DE3143870A1
公开(公告)日：1983-05-11
申请号：DE3143870
申请日：1981-11-05
Applicant: BASF AG
Inventor： SARNECKI WILHELM DIPL CHEM DR , KOVACS JENOE DIPL CHEM DR , LOESER WERNER DIPL ING DR , RUDOLF PETER DIPL CHEM DR , VAETH GUENTER
Abstract: Acicular ferrimagnetic iron oxides are prepared by a process in which iron (III) oxide hydroxide consisting essentially of lepidocrocite is reduced at from 350 DEG to 600 DEG C. by means of an organic compound which is a synthetic polymer with a molecular weight of from 3,000 to 40,000 to give magnetite, which, if desired, is subsequently partially or completely oxidized with an oxygen-containing gas at from 200 DEG to 450 DEG C.
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公开(公告)号：DE2805621A1
公开(公告)日：1979-08-23
申请号：DE2805621
申请日：1978-02-10
Applicant: BASF AG
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公开(公告)号：DE3026696A1
公开(公告)日：1982-02-18
申请号：DE3026696
申请日：1980-07-15
Applicant: BASF AG
Inventor： STECK WERNER DIPL CHEM DR , ROLLER HERMANN , SARNECKI WILHELM DIPL CHEM DR , BALZ WERNER DIPL CHEM DR
Abstract: Ferromagnetic metal particles, consisting essentially of iron and comprising a core, containing not less than 85% by weight of metallic iron, and an iron oxide plus chromium oxide surface layer surrounding this core, which layer additionally contains one or more elements selected from the group comprising zinc, phosphorus in the form of phosphate, aluminum, calcium, strontium, barium, cadmium, lead, cobalt and nickel in a total amount of not more than 9.5% by weight, based on the total amount of the metal particles, and a process for the production of such particles.
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公开(公告)号：DE2935444A1
公开(公告)日：1981-03-19
申请号：DE2935444
申请日：1979-09-01
Applicant: BASF AG
Inventor： SARNECKI WILHELM DIPL CHEM DR , MAROSI LASZLO DIPL CHEM DR , AUTZEN HORST DIPL CHEM DR , OHLINGER MANFRED DIPL CHEM DR , STECK WERNER DIPL CHEM DR
Abstract: A process for the manufacture of acicular ferrimagnetic iron oxide by heating iron(III) oxide or iron(III) oxide hydroxide at 220 DEG -460 DEG C. under a water vapor partial pressure of not less than 30 mbar, reducing the resulting product to magnetite by means of hydrogen and/or CO and/or an organic compound which can decompose in the presence of iron oxide, and then oxidizing the magnetite with an oxygen-containing gas to give acicular ferrimagnetic iron oxide of the formula FeOX, where X is from 1.33 to 1.50.
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Patent Agency Ranking
公开(公告)号：DE2651418A1
公开(公告)日：1978-05-24
申请号：DE2651418
申请日：1976-11-11
Applicant: BASF AG
Inventor： REICH HANS HEINER DIPL CHEM DR , KIENER VOLKER DIPL CHEM DR , SARNECKI WILHELM DIPL CHEM DR , SCHREINER SIEGFRIED DIPL CHEM , WUNSCH GERD DIPL CHEM DR
IPC: C01B17/66 , C01D20060101 , C07C53/06
Abstract: Treating residual mother liquor from prepn. of Na dithionate by reacting SO2 with Na formate and a Na cpd. with a basic reaction in aq. alcoholic medium, comprises distn to separate the alcohol and the organic formate, then acidification to pH 3.0-4.5, heating the soln. to 75-110 degrees C sepg. the S. pptd., and isolating the Na formate by evapn. and cooling. Alternatively, the soln. can be evapd. to dryness, then taken up at 50-100 degrees C in a soln. of Na formate satd. at 20-30 degrees C, filtering, cooling and sepn. of the crystallised formate. No polluting substance is released, while some of the initial reactants of the dithionate prepn. can be recycled.
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公开(公告)号：DE2916403A1
公开(公告)日：1980-11-06
申请号：DE2916403
申请日：1979-04-23
Applicant: BASF AG
Inventor： RUDOLF PETER DIPL CHEM DR , STECK WERNER DIPL CHEM DR , SARNECKI WILHELM DIPL CHEM DR , JAECKH CHRISTOF DIPL CHEM DR
IPC: C01G49/00 , C01G49/02 , C09D5/23 , C09D7/12 , G11B5/70 , G11B5/706 , H01F1/11 , H01F1/36 , G11B5/62 , H01F1/00
Abstract: A process for the manufacture of acicular magnetic iron oxides which consist of a core of gamma-iron(III) oxide and a shell of a magnetite modified with zinc(II) ions and/or manganese(II) ions and which contain, based on the total modified gamma-iron(III) oxide, from 0.1 to 20 percent by weight of iron(II) ions, from 0.1 to 10 percent by weight of zinc(II) ions and/or from 0.1 to 10 percent by weight of manganese(II) ions.
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公开(公告)号：DE2714588A1
公开(公告)日：1978-10-12
申请号：DE2714588
申请日：1977-04-01
Applicant: BASF AG
Inventor： STECK WERNER DIPL CHEM DR , BRODT RUDOLF DIPL CHEM DR , SARNECKI WILHELM DIPL CHEM DR , JAKUSCH HELMUT DIPL PHYS DR , OHLINGER MANFRED DIPL CHEM DR , KOESTER EBERHARD DIPL PHYS DR
IPC: G11B5/706 , B22F9/22 , C09D5/23 , C09D7/12 , C21B15/00 , G11B5/712 , G11B5/714 , H01F1/06 , B22F9/00
Abstract: A process for the manufacture of acicular ferromagnetic iron particles by reducing acicular iron(III) oxide hydroxides which consist of pure synthetic lepidocrocite or a mixture of synthetic goethite and at least 70% by weight of synthetic lepidocrocite. The iron(III) oxide hydroxides used carry, on their surface, an alkaline earth metal cation and an anion of a monobasic, dibasic or tribasic aliphatic carboxylic acid of up to 6 carbon atoms or an organic compound containing at least two groups capable of chelating the alkaline earth metal cation, and are produced in such a way that they consist of at least 70 percent by weight of lepidocrocite and have a length-to-width ratio of not less than 15:1. Reduction of such iron(III) oxide hydroxides gives iron particles with pronounced shape anisotropy, which exhibit both good magnetic properties and a narrow field strength distribution.
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