EP1317513A1 - Procede de fabrication d'un germe d'oxyde de fer contenant de l'aluminium - Google Patents

Procede de fabrication d'un germe d'oxyde de fer contenant de l'aluminium

Info

Publication number
EP1317513A1
EP1317513A1 EP01971964A EP01971964A EP1317513A1 EP 1317513 A1 EP1317513 A1 EP 1317513A1 EP 01971964 A EP01971964 A EP 01971964A EP 01971964 A EP01971964 A EP 01971964A EP 1317513 A1 EP1317513 A1 EP 1317513A1
Authority
EP
European Patent Office
Prior art keywords
mol
feooh
total
content
iron oxide
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.)
Withdrawn
Application number
EP01971964A
Other languages
German (de)
English (en)
Inventor
Ulrich Meisen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Lanxess Deutschland GmbH
Original Assignee
Bayer AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Bayer AG filed Critical Bayer AG
Publication of EP1317513A1 publication Critical patent/EP1317513A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
    • C09C1/22—Compounds of iron
    • C09C1/24—Oxides of iron
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G49/00—Compounds of iron
    • C01G49/0018—Mixed oxides or hydroxides
    • C01G49/0045—Mixed oxides or hydroxides containing aluminium
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/60—Compounds characterised by their crystallite size
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
    • C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/54—Particles characterised by their aspect ratio, i.e. the ratio of sizes in the longest to the shortest dimension
    • 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
    • C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
    • 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
    • C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer
    • 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
    • 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
    • C01P2006/60—Optical properties, e.g. expressed in CIELAB-values
    • 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
    • C01P2006/60—Optical properties, e.g. expressed in CIELAB-values
    • C01P2006/62—L* (lightness axis)
    • 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
    • C01P2006/60—Optical properties, e.g. expressed in CIELAB-values
    • C01P2006/63—Optical properties, e.g. expressed in CIELAB-values a* (red-green axis)
    • 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
    • C01P2006/60—Optical properties, e.g. expressed in CIELAB-values
    • C01P2006/64—Optical properties, e.g. expressed in CIELAB-values b* (yellow-blue axis)

Definitions

  • the present invention relates to a method for producing an aluminum-containing iron oxide nucleus with an ⁇ -FeOOH crystal structure from FeCl 2 .
  • This germ is suitable as a starting material for the production of iron oxide yellow and for use as a yellow color pigment.
  • Synthetic iron oxides are usually prepared by the method Laux-, the pen niman- method, the precipitation process, the neutralization process or the roasting process (Ullmann's Encyclopedia of Industrial Chemistry, 5 th edition, 1992, volume A20, page 297 ff).
  • the iron oxides thus obtained are generally used as pigments.
  • an iron (II) component i.e. an iron salt dissolved in water
  • an alkaline component usually an alkali or alkaline earth metal compound or ammonia solution dissolved or suspended in water
  • the amount of alkaline component added is generally between 15% and 70% of the stoichiometrically required amount.
  • the pH is in the weakly acidic range.
  • an oxidizing agent usually atmospheric oxygen, is used for the oxidation.
  • the reaction is carried out at temperatures between 20 ° C and 50 ° C. At significantly higher temperatures the risk of undesirable magnetite formation.
  • the end point of the reaction can be recognized by a sharp drop in the pH value and the redox potential.
  • germ the properties of the product obtained (generally called germ) are determined and, if suitable, this is further processed directly to give the ⁇ -FeOOH pigment.
  • the alkaline process differs from the acid process in the amount of the alkaline component added. In the alkaline process, this is at least 120% of the stoichiometrically required amount, but is generally significantly higher.
  • the temperatures at which this reaction is carried out can be somewhat higher than the temperatures used in the acidic process, since the risk of magnetite formation is lower here.
  • the alkaline process gives relatively long-needle ⁇ -FeOOH crystallites with a length to width ratio of 10: 1 to 30: 1. Since these crystals are also very low in dendrites, this process is particularly suitable for the production of ⁇ -FeOOH as a starting product for magnetic tapes.
  • the germs produced by the alkaline process cannot be used directly, or can only be used to a limited extent, since all of the coloring metals present in the Fe component are incorporated in this process. These metals (especially Mn, Cr, Cu, Ni) significantly impair the color properties and thus restrict the use of germs produced in this way as color pigments.
  • an ⁇ -FeOOH seed is preferably used and this is then coarsened (built up) in acid, which reduces the incorporation of the coloring metals. Furthermore, the build-up may only be carried out at pH values of less than approx. 4, since at higher pH values the coloring metals are incorporated to an increasing extent. Furthermore, the partial the shape of the ⁇ -FeOOH, the color properties, the viscosity of the lacquer and the need for binding agents.
  • short-needle ⁇ -FeOOH particles are required. These can be produced from long-needle ⁇ -FeOOH particles by intensive grinding. A cheaper alternative is the direct production of short-needle ⁇ -FeOOH particles.
  • FeCl 2 Although the use of FeCl 2 is described in this patent, precise conditions for producing an ⁇ -FeOOH nucleus from FeCl are not mentioned. However, since FeCl 2 , especially in the nucleation phase, differs significantly from
  • FeSO differs, the conditions under which a good pigment is obtained with FeSO cannot be transferred to FeCl.
  • the present invention was based on the object of a method for the simple and inexpensive production of a short-needle ⁇ -FeOOH germ after
  • this c-FeOOH seed is built up to an ⁇ -FeOOH pigment.
  • FeOOH crystal structure with an aspect ratio AV of 2100 to 3600 and one BET surface area from 50 to 150 m2 / g.
  • the aspect ratio is the product of the BET surface area and the average crystallite size, which was determined by X-ray analysis from the 110 reflex of the ⁇ -FeOOH.
  • this mixture is heated to a falling temperature between 30 ° C. and 60 ° C., preferably 35-50 degrees,
  • the precipitated suspension is then oxidized with an oxidizing agent at such a rate that the oxidation rate is 2-50 mol% / h, preferably 10-35 mol% / h of the iron to be oxidized and
  • the Al-containing ⁇ -FeOOH nucleus obtained after the oxidation are optionally isolated.
  • the Al-containing ⁇ -FeOOH nucleus obtained after the oxidation can optionally be used without further isolation, after testing the properties, for the production of iron oxide yellow pigments.
  • FeCl 2 solution with an Fe content of 55 g / 1 Fe, of which 1.5 mol% Fe-L ⁇ AlCl solution, NaOH solution with an NaOH content of 300 g / 1 7.5 equivalents of NaOH / 1
  • Oxidation rate 30 - 35 mol% Fe-II / h
  • A1C1 3 (as an aqueous solution) is preferably used as Al component.
  • Si or Ti as a seed modifier, in the form of their chlorides, is also possible, but requires a higher technical outlay in production.
  • Ca (OH) 2 , CaO, CaCO, NH or secondary or tertiary aliphatic amines can be used in aqueous solution or aqueous slurry.
  • Atmospheric oxygen, oxygen, ozone, H 2 O 2 , chlorine, nitrates of the alkali or alkaline earth metals or NH NO 3 are used as oxidizing agents.
  • the iron-chloride solution used contains larger amounts at pH values of less than 4 precipitable coloring metals, these can be precipitated by adding an alkaline component to the iron-II-chloride solution up to pH 4.
  • the resulting solid can be separated from the supernatant clear, purified solution by sedimentation, filtration or centrifugation.
  • Desired coloring metals are also Fe-HI removed, which significantly undesirably influences the reaction to the ⁇ -FeOOH germ (formation of black magnetite).
  • the reaction is carried out in batch or continuous stirred tanks, in
  • the ⁇ -FeOOH nuclei according to the invention After the ⁇ -FeOOH nuclei according to the invention have been produced, they are converted into a pigment, which is done by means of coarsening of the nuclei particles known per se (pigment build-up). However, since the ⁇ -FeOOH nuclei according to the invention are not used as such, it is necessary to describe the pigment structure to form an iron oxide yellow pigment.
  • the Al-containing seed produced by the process according to the invention is pumped to a solution of FeCl or FeSO 4 or another Fe-H salt.
  • 7 - 15 mol of Fe-11 salt as a solution with an Fe content of 30 - 100 g / 1 Fe are added to one mol of FeOOH in the nucleus.
  • Adding higher amounts of Fe-II salt also leads to ⁇ -FeOOH yellow pigments, but the brightness decreases with increasing amount of Fe-II salts added, which is generally undesirable.
  • This suspension is then heated to the reaction temperature, which is between 50 ° C and 90 ° C. After the fall temperature has been reached, oxidation and precipitation are started at the same time.
  • atmospheric oxygen is added via a suitable gassing device and the pH of the suspension is regulated with an alkaline precipitant.
  • the pH value is regulated in a range from 2.4 to 4.8.
  • the oxidation rate should be between 0.5 and 8 mol% Fe-i ⁇ / h.
  • the solid formed is separated off by filtration. It is washed salt-free and can then be dried.
  • the yellow pigment produced by this process is characterized by high color purity, almost isometric particle shape, low oil number and high chemical purity. The sum of its properties makes it particularly suitable for:
  • This process is particularly economical due to the inexpensive raw materials and the high production rate in yellow pigment production. Due to the special reaction procedure and the use of a precisely specified germ, it is possible to safely produce particularly high-quality yellow pigments, which have application advantages compared to pigments produced by other processes. Environmentally relevant chemicals are not used in the production of the yellow pigments according to the invention.
  • the BET surface area is determined according to the so-called 1-point method according to DIN 66131.
  • the crystallite size is determined on the Phillips powder diffractometer.
  • the 110 reflex is used to determine the crystallite size.
  • the determination in goethite is carried out after X-ray diffractometric irradiation by reflection detection.
  • the evaluation is carried out using silicon as an external standard.
  • 2.6.2.2 Place about 1 g sample in the sample holder (4.6) of the diffractometer and start the measurement program.
  • Example 1 Aluminum-containing germ from FeCl 2 and AIC1 3
  • the FeCl 2 amount corresponded to 13.9 mol Fe (Fe-fl and Fe-ITI), the AlCl 3 amount 1.71 mol, the HCl amount 0.989 mol.
  • the Al Fe total ratio accordingly corresponded to 12.3 mol% based on total Fe.
  • This solution was heated to 44 ° C. with stirring and gassing with 300 Nl / h nitrogen. After this temperature had been reached, 1615 ml of sodium hydroxide solution containing 300 g of NaOH / 1 (corresponding to 7.5 equivalents per liter) were pumped in in 6 minutes using a gear pump. Accordingly, 33.8% of the metals Fe + Al were precipitated. Immediately after the precipitation had ended, the gassing was stopped with nitrogen and 97 Nl / h of air were gassed for the purpose of oxidation. 180 minutes after
  • the germ obtained had the following properties:
  • the FeCl 2 amount corresponds to 13.9 mol Fe (Fe-E and Fe-HI), the AlCl 3 amount 1.71 mol, the HCl amount 0.989 mol.
  • the ratio Al / Fe total therefore corresponds to 12.3 mol% based on total Fe.
  • This solution is heated to 34 ° C. with stirring and gassing with 300 Nl / h nitrogen. After this temperature has been reached, 1615 ml of sodium hydroxide solution with a content of 300 g NaOH / 1 (corresponding to 7.5 equivalents per liter) are pumped in in 6 minutes using a gear pump. Accordingly, 33.8% of the Fe + AI metals are precipitated by NaOH.
  • the germ had the following properties:
  • the FeCl 2 amount corresponds to 9.5 mol Fe (Fe-H and Fe-uT), the AlCl 3 amount 1.82 mol, the HCl amount 0.36 mol.
  • the ratio Al / Fe total corresponds accordingly
  • the germ had the following properties:
  • the yellow pigment produced has the following properties:
  • the germ from example 2 is used and the amount of air is set to 76 Nl / h, the reaction conditions obtained are otherwise identical after 1618 minutes (oxidation rate 3.7 mol% / h)
  • Crystallite size 25 nm color strength (against Bayferrox ® 915): 97% da *: 0.1 db *: -2.6 dL * (against Bayferrox ® 915): -3.4 da *: 1.1 db *: -4.0

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Nanotechnology (AREA)
  • Physics & Mathematics (AREA)
  • Composite Materials (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Compounds Of Iron (AREA)

Abstract

La présente invention concerne un procédé de fabrication d'un germe d'oxyde de fer contenant de l'aluminium, présentant une structure cristalline α-FeOOH constituée de FeCl2. Ledit germe sert de matériau de base pour la fabrication d'oxyde de fer jaune et peut être utilisé en tant que pigment jaune.
EP01971964A 2000-09-07 2001-08-27 Procede de fabrication d'un germe d'oxyde de fer contenant de l'aluminium Withdrawn EP1317513A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10044097A DE10044097A1 (de) 2000-09-07 2000-09-07 Verfahren zur Herstellung eines aluminiumhaltigen Eisenoxidkeims
DE10044097 2000-09-07
PCT/EP2001/009835 WO2002020673A1 (fr) 2000-09-07 2001-08-27 Procede de fabrication d'un germe d'oxyde de fer contenant de l'aluminium

Publications (1)

Publication Number Publication Date
EP1317513A1 true EP1317513A1 (fr) 2003-06-11

Family

ID=7655306

Family Applications (1)

Application Number Title Priority Date Filing Date
EP01971964A Withdrawn EP1317513A1 (fr) 2000-09-07 2001-08-27 Procede de fabrication d'un germe d'oxyde de fer contenant de l'aluminium

Country Status (6)

Country Link
US (1) US6508290B2 (fr)
EP (1) EP1317513A1 (fr)
AU (1) AU2001291799A1 (fr)
CA (1) CA2421189A1 (fr)
DE (1) DE10044097A1 (fr)
WO (1) WO2002020673A1 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
PL1512726T3 (pl) * 2003-09-03 2016-03-31 Lanxess Deutschland Gmbh Sposób wytwarzania żółtych pigmentów tlenku żelaza z CaCO3 jako środkiem strącającym
CN104383862B (zh) * 2014-11-22 2016-02-03 山东阳谷华泰化工股份有限公司 用于合成橡胶促进剂ns的生产设备及应用
CN104772098A (zh) * 2015-04-16 2015-07-15 株洲冶炼集团股份有限公司 一种带有加热加氧装置的反应釜
CN111339665A (zh) * 2020-02-27 2020-06-26 中国科学院空天信息创新研究院 一种对流层臭氧廓线计算方法

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3326632A1 (de) 1983-07-23 1985-02-07 Bayer Ag, 5090 Leverkusen Neue eisenoxidgelbpigmente mit niedrigem silking-effekt sowie deren herstellung
US4618375A (en) * 1984-10-04 1986-10-21 Basf Corporation Transparent iron oxide pigments
WO1997034830A1 (fr) * 1996-03-21 1997-09-25 Dowa Mining Co., Ltd. Poudre pour sous-couche de support d'enregistrement magnetique de type a revetement
DE19652953C2 (de) * 1996-12-19 2000-05-18 Bayer Ag Verfahren zur Herstellung von Eisenoxidkeimen und deren Verwendung
DE19746262A1 (de) * 1997-10-20 1999-04-22 Bayer Ag Eisenoxidrotpigmente, Verfahren zur Herstellung von Eisenoxidrotpigmenten und deren Verwendung
DE19746263A1 (de) * 1997-10-20 1999-04-22 Bayer Ag Eisenoxidgelbpigmente, Verfahren zur Herstellung von Eisenoxidgelbpigmenten und deren Verwendung
DE19751141A1 (de) * 1997-11-19 1999-05-20 Bayer Ag Nicht-silkende Eisenoxidgelb-Pigmente mit hoher Buntheit
EP0982377A1 (fr) * 1998-08-28 2000-03-01 Toda Kogyo Corp. Pigment fin composite d'oxyde hydroxyde de fer jaune, et composition de peinture ou de résine le contenant

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0220673A1 *

Also Published As

Publication number Publication date
CA2421189A1 (fr) 2002-03-14
WO2002020673A1 (fr) 2002-03-14
DE10044097A1 (de) 2002-04-04
US20020127176A1 (en) 2002-09-12
AU2001291799A1 (en) 2002-03-22
US6508290B2 (en) 2003-01-21

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