WO2009100767A1 - Process for producing red iron oxide - Google Patents
Process for producing red iron oxide Download PDFInfo
- Publication number
- WO2009100767A1 WO2009100767A1 PCT/EP2008/051896 EP2008051896W WO2009100767A1 WO 2009100767 A1 WO2009100767 A1 WO 2009100767A1 EP 2008051896 W EP2008051896 W EP 2008051896W WO 2009100767 A1 WO2009100767 A1 WO 2009100767A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- lepidocrocite
- seeds
- ferrous chloride
- surface area
- feedstock
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 50
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 title claims abstract description 23
- AEIXRCIKZIZYPM-UHFFFAOYSA-M hydroxy(oxo)iron Chemical compound [O][Fe]O AEIXRCIKZIZYPM-UHFFFAOYSA-M 0.000 claims abstract description 67
- 229960002089 ferrous chloride Drugs 0.000 claims abstract description 49
- NMCUIPGRVMDVDB-UHFFFAOYSA-L iron dichloride Chemical compound Cl[Fe]Cl NMCUIPGRVMDVDB-UHFFFAOYSA-L 0.000 claims abstract description 49
- 239000003513 alkali Substances 0.000 claims abstract description 25
- 239000000203 mixture Substances 0.000 claims abstract description 21
- 230000001590 oxidative effect Effects 0.000 claims abstract description 9
- 238000002156 mixing Methods 0.000 claims abstract description 8
- 230000001376 precipitating effect Effects 0.000 claims abstract description 6
- 230000003113 alkalizing effect Effects 0.000 claims abstract description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 40
- 229910052742 iron Inorganic materials 0.000 claims description 20
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 18
- 238000007254 oxidation reaction Methods 0.000 claims description 15
- 230000003647 oxidation Effects 0.000 claims description 14
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 13
- 238000001556 precipitation Methods 0.000 claims description 12
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 9
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 claims description 8
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 8
- 239000001301 oxygen Substances 0.000 claims description 8
- 229910052760 oxygen Inorganic materials 0.000 claims description 8
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 4
- 229910021529 ammonia Inorganic materials 0.000 claims description 4
- 150000003841 chloride salts Chemical class 0.000 claims description 4
- 239000003570 air Substances 0.000 claims description 2
- 239000007800 oxidant agent Substances 0.000 claims description 2
- 229910052598 goethite Inorganic materials 0.000 abstract description 24
- 239000007858 starting material Substances 0.000 abstract description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 24
- 235000013980 iron oxide Nutrition 0.000 description 16
- 239000000243 solution Substances 0.000 description 12
- 229910052595 hematite Inorganic materials 0.000 description 10
- 239000011019 hematite Substances 0.000 description 10
- LIKBJVNGSGBSGK-UHFFFAOYSA-N iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Fe+3].[Fe+3] LIKBJVNGSGBSGK-UHFFFAOYSA-N 0.000 description 10
- VBMVTYDPPZVILR-UHFFFAOYSA-N iron(2+);oxygen(2-) Chemical class [O-2].[Fe+2] VBMVTYDPPZVILR-UHFFFAOYSA-N 0.000 description 9
- 239000000047 product Substances 0.000 description 8
- 239000001034 iron oxide pigment Substances 0.000 description 6
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 5
- 239000005569 Iron sulphate Substances 0.000 description 5
- 239000006227 byproduct Substances 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 5
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 238000005554 pickling Methods 0.000 description 5
- 239000011541 reaction mixture Substances 0.000 description 5
- 239000012266 salt solution Substances 0.000 description 5
- 239000000523 sample Substances 0.000 description 5
- 239000002699 waste material Substances 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 4
- 239000013078 crystal Substances 0.000 description 4
- 239000011790 ferrous sulphate Substances 0.000 description 4
- 235000003891 ferrous sulphate Nutrition 0.000 description 4
- 239000000049 pigment Substances 0.000 description 4
- 150000003839 salts Chemical class 0.000 description 4
- 239000010959 steel Substances 0.000 description 4
- 229910021653 sulphate ion Inorganic materials 0.000 description 4
- 239000001117 sulphuric acid Substances 0.000 description 4
- 235000011149 sulphuric acid Nutrition 0.000 description 4
- 239000011701 zinc Substances 0.000 description 4
- 229910052725 zinc Inorganic materials 0.000 description 4
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 3
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 3
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 3
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 3
- 238000002441 X-ray diffraction Methods 0.000 description 3
- 239000004411 aluminium Substances 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000001354 calcination Methods 0.000 description 3
- 229910052791 calcium Inorganic materials 0.000 description 3
- 239000011575 calcium Substances 0.000 description 3
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 3
- 239000004568 cement Substances 0.000 description 3
- 229910052804 chromium Inorganic materials 0.000 description 3
- 239000011651 chromium Substances 0.000 description 3
- 238000004040 coloring Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- 229910052749 magnesium Inorganic materials 0.000 description 3
- 239000011777 magnesium Substances 0.000 description 3
- 229910052748 manganese Inorganic materials 0.000 description 3
- 239000011572 manganese Substances 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- 241000894007 species Species 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 2
- 241000196324 Embryophyta Species 0.000 description 2
- YNQLUTRBYVCPMQ-UHFFFAOYSA-N Ethylbenzene Chemical compound CCC1=CC=CC=C1 YNQLUTRBYVCPMQ-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 230000002378 acidificating effect Effects 0.000 description 2
- 238000013019 agitation Methods 0.000 description 2
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 2
- 150000001342 alkaline earth metals Chemical class 0.000 description 2
- 239000011324 bead Substances 0.000 description 2
- 239000000356 contaminant Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- YDZQQRWRVYGNER-UHFFFAOYSA-N iron;titanium;trihydrate Chemical compound O.O.O.[Ti].[Fe] YDZQQRWRVYGNER-UHFFFAOYSA-N 0.000 description 2
- 238000002386 leaching Methods 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000000123 paper Substances 0.000 description 2
- YPFNIPKMNMDDDB-UHFFFAOYSA-K 2-[2-[bis(carboxylatomethyl)amino]ethyl-(2-hydroxyethyl)amino]acetate;iron(3+) Chemical compound [Fe+3].OCCN(CC([O-])=O)CCN(CC([O-])=O)CC([O-])=O YPFNIPKMNMDDDB-UHFFFAOYSA-K 0.000 description 1
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical compound [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 description 1
- 241000871495 Heeria argentea Species 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 239000005864 Sulphur Substances 0.000 description 1
- 150000001447 alkali salts Chemical class 0.000 description 1
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 description 1
- 229910052921 ammonium sulfate Inorganic materials 0.000 description 1
- 239000001166 ammonium sulphate Substances 0.000 description 1
- 235000011130 ammonium sulphate Nutrition 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000001110 calcium chloride Substances 0.000 description 1
- 229910001628 calcium chloride Inorganic materials 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 239000000920 calcium hydroxide Substances 0.000 description 1
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- JOPOVCBBYLSVDA-UHFFFAOYSA-N chromium(6+) Chemical compound [Cr+6] JOPOVCBBYLSVDA-UHFFFAOYSA-N 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 239000003086 colorant Substances 0.000 description 1
- 239000004035 construction material Substances 0.000 description 1
- 239000013068 control sample Substances 0.000 description 1
- 239000002537 cosmetic Substances 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000012065 filter cake Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 229910052602 gypsum Inorganic materials 0.000 description 1
- 239000010440 gypsum Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 235000014413 iron hydroxide Nutrition 0.000 description 1
- IEECXTSVVFWGSE-UHFFFAOYSA-M iron(3+);oxygen(2-);hydroxide Chemical compound [OH-].[O-2].[Fe+3] IEECXTSVVFWGSE-UHFFFAOYSA-M 0.000 description 1
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 1
- NCNCGGDMXMBVIA-UHFFFAOYSA-L iron(ii) hydroxide Chemical compound [OH-].[OH-].[Fe+2] NCNCGGDMXMBVIA-UHFFFAOYSA-L 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 238000010943 off-gassing Methods 0.000 description 1
- NDLPOXTZKUMGOV-UHFFFAOYSA-N oxo(oxoferriooxy)iron hydrate Chemical compound O.O=[Fe]O[Fe]=O NDLPOXTZKUMGOV-UHFFFAOYSA-N 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- JTJMJGYZQZDUJJ-UHFFFAOYSA-N phencyclidine Chemical compound C1CCCCN1C1(C=2C=CC=CC=2)CCCCC1 JTJMJGYZQZDUJJ-UHFFFAOYSA-N 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 238000011085 pressure filtration Methods 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000002829 reductive effect Effects 0.000 description 1
- 239000002760 rocket fuel Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000007873 sieving Methods 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- PMZURENOXWZQFD-UHFFFAOYSA-L sodium sulphate Substances [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 1
- 235000011152 sodium sulphate Nutrition 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000007669 thermal treatment Methods 0.000 description 1
- 239000004408 titanium dioxide Substances 0.000 description 1
- 238000003828 vacuum filtration Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 229910006299 γ-FeOOH Inorganic materials 0.000 description 1
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
-
- 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]
-
- 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
- C01P2006/12—Surface area
- C01P2006/13—Surface area thermal stability thereof at high temperatures
-
- 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 process for producing red iron oxide and, more particularly, to a process for producing red iron oxide with only marginal goethite content.
- Red iron oxides are commonly used as pigments for colouring of construction materials, paints and coatings, plastics, paper, cosmetics and the like. In addition they may be used as catalysts in chemical reactions such as conversion of ethylbenzene to styrene and as burn rate control agents for solid rocket fuel. For these applications products typically have a small (0.1 micron to 3 micron particle size and preferably consist of pure hematite crystals with minimal content of other iron oxide crystal types.
- red iron oxides production processes based on iron sulphate.
- sulphur gases are released which must be collected and converted back to sulphuric acid in a sulphuric acid plant while not reacted iron sulphate in the product is typically neutralized to give a gypsum waste stream.
- precipitation processes a salt solution is generated which must be treated before release to the environment, typically by evaporation to sodium or ammonium sulphate.
- red iron oxides obtained from sulphate precipitation processes usually contain significant quantities of goethite which reduces the brightness and colouring strength of the hematite pigment.
- ferrous chloride solutions are more readily available, for example, from pickling of steel or benef ⁇ ciation of ilmenite ores by acid leaching processes.
- ferrous chloride pickling wastes have been disposed by roasting to recycle the hydrochloric acid value while generating a very low value iron oxide by-product.
- ferrous chloride pickling wastes are neutralized and disposed in a landfill.
- the ferrous chloride by-products contain a significant level of impurities such as manganese and zinc, which can have negative effects on pigment production processes.
- French patent 1498479 describes a process for precipitation of an iron hydroxide gel or goethite from a ferric salt solution and subsequent thermal treatment under hydrothermal conditions (above 100 0 C), typically above 12O 0 C and up to 25O 0 C to transform this gel to ferric oxide.
- a process for production of red iron oxide pigments from ferrous chloride solutions with the added advantage of calcium chloride recovery is described in Indian patent 174841.
- the process involves neutralization of the ferrous chloride with calcium hydroxide followed by oxidation over 4 to 6 hours, separation of the calcium chloride solution for recovery, washing, drying and calcining the product iron oxide at 750 0 C to 800 0 C to achieve the target iron oxide.
- German patent 1040155 discloses a process for precipitation of red iron oxides without a calcination step.
- Metallic iron is treated with oxygen containing gases in an aqueous iron (II) salt solution containing seeds of iron oxide or iron oxide hydroxide, wherein the seeds are prepared from precipitation of iron (II) ions by addition of alkali or alkaline earth hydroxides or carbonates. Both ferrous sulphate and ferrous chloride are suitable.
- US patent 7144455 relates to a method for precipitating yellow iron oxide pigments (goethite) from ferrous chloride solutions and their use in preparing red iron oxide pigments by calcination.
- red oxides in chloride and sulphate systems there are significant differences between growth of red oxides in chloride and sulphate systems.
- the seed is typically a mixture of various iron oxide species including but not limited to one or more of hematite, goethite, lepidocrocite and/or magnetite. When grown at normal conditions in the presence of metallic iron at elevated temperatures all of these species typically convert to small particle hematite.
- the goethite seeds will not transform to hematite but persist as goethite throughout the growth reaction with a significant negative effect on the red colour quality.
- a process for producing red iron oxide comprising the steps of providing a ferrous chloride feedstock, precipitating high surface area lepidocrocite seeds having a BET surface area of greater than about 175 m 2 /g by mixing the ferrous chloride feedstock with an alkali, oxidizing the obtained mixture, and growing the lepidocrocite seeds, whereby the lepidocrocite converts into red iron oxide.
- high surface area lepidocrocite seeds having a BET surface area of greater than about 175 m 2 /g are provided.
- the high surface area lepidocrocite seeds are obtainable by a process, comprising providing a ferrous chloride feedstock, and precipitating the high surface area lepidocrocite seeds having a BET surface area of greater than about 175 m 2 /g by mixing the ferrous chloride feedstock with an alkali and oxidizing the obtained mixture.
- the ferrous chloride feedstock can have any ferrous iron concentration above 5%, e.g. from 15% to 22%, or about 20%.
- the ferrous chloride feedstock can be diluted for the precipitation of the seeds and can contain iron concentrations from about 5 to 100 g/1, such as from about 20 to 50 g/1, or from about 30 to 40 g/1.
- the ferrous chloride feedstock can be a waste or by-product obtained from industrial processes, e.g., from pickling of steel or benef ⁇ ciation of ilmenite ores by acid leaching processes.
- Ferrous chloride by-product or waste solutions suitable for the process of exemplary embodiments of this invention may contain significant levels of impurities.
- the ferrous chloride feedstock can contain at least one of ferric iron, aluminium, calcium, chromium, magnesium, manganese, or zinc, or any other contaminant typically occurring in technical grade feedstocks.
- ferrous iron can be present in any amount that is soluble in the feedstock, e.g., up to 23%, or at about 20%.
- aluminium can be present in the feedstock in an amount from 0 to 1200 ppm, such as from about 300 to 900 ppm, or at about 600 ppm.
- calcium can be present in an amount from 0 to 2300 ppm, such as from about 750 to 1500 ppm, or at about 1100 ppm.
- chromium can be present in an amount from 0 to 300 ppm, such as from about 80 to 230 ppm, or at about 150 ppm.
- magnesium can be present in an amount from 0 to 4600 ppm, such as from 1500 to 3000 ppm, or at about 2300 ppm.
- manganese can be present in the feedstock in an amount from 0 to 2300 ppm, such as from 750 to 1500 ppm, or at about 1100 ppm.
- zinc can be present in an amount from 0 to 300 ppm, such as from 80 to 230 ppm, or at about 150 ppm.
- the type and amount of impurities can differ from those set out above.
- the ferrous chloride feedstock contains about 15% ferrous iron, and, independently of each other, about 600 ppm aluminium, and/or about 1100 ppm calcium, and/or about 150 ppm chromium, and/or about 225 ppm magnesium, and/or about 1100 ppm manganese and/or about 150 ppm zinc.
- the ferrous chloride feedstock may be pre-treated before use in the process of exemplary embodiments of the invention, for example, to remove contaminants or other undesirable components.
- the process for producing red iron oxide further comprises the step of first purifying the ferrous chloride feedstock, for example, by reacting with one of iron or alkali.
- the alkali can be, e.g., selected from at least one of sodium hydroxide, potassium hydroxide or ammonia, or other suitable alkalis such as carbonates of alkaline or alkaline earth metals.
- the purification can be carried out at an acidic pH value, for example, a pH from about 3 to 5.
- the high surface area lepidocrocite seeds are precipitated by mixing the ferrous chloride feedstock with an alkali and oxidizing the obtained mixture.
- the high surface area lepidocrocite ( ⁇ -FeOOH) seeds have a BET surface area of greater than about 175 m 2 /g.
- the BET surface area of the precipitated lepidocrocite seeds can be determined using the single point method in accordance with DIN 66131, wherein the seeds previously have been out-gassed under nitrogen for 15 min at a temperature of 150 0 C.
- the precipitation can be carried out at temperatures from about 5 to 25°C, from about 10 to 20 0 C, or from about 12 to 17°C. Without wishing to be bound to any theory, it is believed that low temperatures favour the formation of lepidocrocite seeds having higher surface areas.
- the alkali can be added in an almost stoichiometric amount, e.g. in an amount that is sufficient to precipitate 90 to 110% of the iron present in the ferrous chloride feedstock.
- the alkali can be selected from at least one of sodium hydroxide, potassium hydroxide or ammonia. Other potentially suitable alkalis such as carbonates of alkaline or alkaline earth metals may also be used.
- the final pH value of the mixture can be from about 3 to 9.
- the particle or crystallite size of the seeds should be kept as low as possible. In the embodiments of the invention this can be achieved by one or several measures as described in the following.
- one option is that the oxidation is rapidly carried out in about 20 to 80 minutes, preferably in less than one hour, such as from about 10 to 60 minutes, or from about 15 to 45 minutes.
- the oxidant can be selected from at least one of air, oxygen, or hydrogen peroxide. Rapid oxidation, i.e. oxidation within a short period of time, has a beneficial effect on the formation of high surface area lepidocrocite.
- another option is that the oxidation is carried out simultaneously with mixing the alkali and the ferrous chloride feedstock.
- the oxidation rate in the reaction mixture at the time of alkali addition is sufficient to oxidize the just precipitated seeds substantially instantaneously to lepidocrocite.
- the inventors have observed that a precipitation which proceeds too fast in relation to the oxidation rate will generate lepidocrocite seeds having a low BET surface area (i.e.
- All these options may be used individually or in combination with each other to produce the lepidocrocite having the desired high surface area.
- the processes of the embodiments of the invention can be carried out in any reactor arrangement that is suitable for precipitation and oxidation reactions, e.g., in a vessel with an air sparger, a vessel with a mechanical agitator, particularly a high efficiency agitator to promote gas dispersion, or a vessels arranged with an internal or external recirculation system.
- the processes of the embodiments of the invention can be carried out in the presence of a recycled chloride salt solution which enables a higher salt concentration in the final solution.
- the salts of the final solution are recycled.
- the growing of the lepidocrocite seeds is accomplished by adding further ferrous chloride feedstock and alkali to the obtained mixture comprising the precipitated high surface lepidocrocite seeds.
- the ferrous chloride feedstock can be used undiluted, having an ferrous iron concentration from about 5 to 23%, preferably about 15%.
- the alkali may be one of those described above. The addition may be done simultaneously or sequentially in any order.
- the lepidocrocite converts into red iron oxide.
- the growing of the lepidocrocite seeds can be carried out at temperatures equal or above 80 0 C, such as from about 80 to 110 0 C, such as from about 85 to 95°C, preferably from about 90 to 95°C, at a suitable pH of the mixture, depending on the type, amount and ratio of alkali and ferrous chloride feedstock added.
- the growing of the seeds can be carried out at an overall acidic pH, e.g. a pH value from about 3.5 to 5.5.
- the growing of the lepidocrocite seeds can be accomplished by oxidizing at high temperatures in the presence of metallic iron.
- the growing of the lepidocrocite seeds can be carried out at temperatures above about 80 0 C.
- the alkali salt formed can be separated and recovered.
- the resulting red iron oxide suspension is filtered and washed, e.g. by conventional processes such as vacuum or pressure filtration, to remove water soluble salts.
- the obtained filter cake can be dried and milled by conventional means to give the useful red iron oxide suitable for colouring applications.
- the chloride salts formed during the processes of the embodiments of the invention can be recycled.
- the filtration is carried out in such a way that a high chloride salt solution is obtained which can be used for salt recovery.
- the crystal phases present in the obtained seeds and red iron oxides can be determined by XRD measurements.
- XRD measurements were done using a Philips XPert-Pro diffractometer using cobalt radiation.
- the BET surface area of the samples was determined using the single point method in accordance with DIN 66131 after out-gassing the sample for 15 minutes at 15O 0 C under nitrogen.
- Colour measurements were performed by preparing a mixture of 0.5 g of the obtained red iron oxide in 30 g of white cement (Acquila Bianca), which has been sieved through a 600 mesh sieve, with 50 g of 3mm glass beads. The mixture was shaken for 16 min. Subsequently, the beads were separated by sieving through a 100 mesh sieve and the coloured cement was pressed out on paper using a glass plate. The colour value was determined using a Gardner spectrophotometer under D65 illumination (2° observer with specular component excluded). The colours were compared to commercial iron oxide pigments supplied by Rockwood Pigments, namely Ferroxide 212 and Ferroxide 218. The data are reported in CIELAB units.
- a 20 1 vessel equipped with an agitator was charged with a ferrous sulphate solution having an iron concentration of 22 g/1.
- the initial temperature was 17°C.
- sodium hydroxide was added in an amount that is sufficient to precipitate 92% of the iron present.
- the mixture was simultaneously oxidized with oxygen at a rate of 300 1/h over a time period of 100 min.
- the final pH was 4.4 and the final temperature 25°C.
- the seed had a BET surface area of 120 m 2 /g and exhibited a significant amount of goethite phase.
- the seed was heated to 90 0 C over 7 hours. After this treatment the seed contained a mixed phase of goethite and hematite with a surface area of 68 m 2 /g.
- a 20 1 vessel equipped with an agitator was charged with a ferrous chloride solution having an iron concentration of 22 g/1.
- the initial temperature was 17°C.
- sodium hydroxide was added in an amount that is sufficient to precipitate 92% of the iron present.
- the mixture was simultaneously oxidized with oxygen at a rate of 750 1/h over a time period of 74 min.
- the final pH was 3.2 and the final temperature 31 0 C.
- the seed had a BET surface area of 95 m 2 /g and exhibited a mixed phase of lepidocrocite and goethite.
- the seed was heated to 90 0 C over 7 hours. After this treatment the seed constituted a goethite phase with a BET surface area of 62 m 2 /g.
- the suspension was oxidized with air at 90 0 C with the simultaneous addition of ferrous chloride and ammonia to maintain a pH around 5.0.
- the final product consisted principally of goethite and was not comparable to the target red shades Ferroxide 212 or Ferroxide 218.
- a 300 1 reactor equipped with an agitator was charged with 180 1 of a ferrous chloride solution having an iron concentration of 24 g/1.
- the initial temperature was 24°C.
- aqueous ammonia was added in an amount that is sufficient to precipitate 95% of the iron present.
- the mixture was simultaneously oxidized with oxygen at a rate of 10 m /h over a time period of 35 min.
- the final pH was 5.0 and the final temperature 33°C.
- the seed had a BET surface area of 120 m 2 /g and exhibited primarily lepidocrocite but with a significant component of goethite.
- the seed was heated to 90 0 C over 3.25 hours.
- the seeds in the reaction mixture were grown by a simultaneous addition of ferrous chloride and aqueous ammonia at a pH of 4.0 to yield 18O g product from 60 g seed. At that point the colour values were very light, much less red and blue compared to standard Ferroxide 212. X-ray diffraction revealed that the sample was a mixture of hematite and goethite.
- the oxidation rate at seed formation was apparently insufficient, probably due to insufficient agitation and/or insufficient oxidation rate.
- Example 1 A 20 1 vessel equipped with an agitator was charged with a ferrous chloride solution having an iron concentration of 26 g/1. The initial temperature was 12°C. Over a time period of 20 min sodium hydroxide was added in an amount that is sufficient to precipitate 110% of the iron present. Then, the mixture was oxidized with oxygen at a rate of 700 1/h over a time period of 44 min. The final pH was 8.9 and the final temperature 24°C. The seed had a BET surface area of 190 m 2 /g and exhibited a phase of lepidocrocite.
- the seed was heated to 90 0 C over 2 hours. After this treatment the seed still exhibited a lepidocrocite phase with a BET surface area of 185 m 2 /g.
- the seeds in the reaction mixture were grown by a simultaneous addition of ferrous chloride and aqueous ammonia at a pH of 4.0 to yield 225 g product from 60 g seeds. At that point the colour values were slightly greener than the standard Ferroxide 212.
- a 300 1 reactor equipped with an agitator was charged with 180 1 of a ferrous chloride solution having an iron concentration of 25 g/1.
- the initial temperature was 25°C.
- aqueous ammonia was added in an amount that is sufficient to precipitate 95% of the iron present.
- the mixture was simultaneously oxidized with oxygen at a rate of 15 m 3 /h over a time period of 40 min.
- the final pH was 5.0 and the final temperature 33°C.
- the seed had a BET surface area of 290 m 2 /g and exhibited only lepidocrocite.
- the seed was heated to 90 0 C over 4 hours. After this treatment the seed still exhibited a lepidocrocite phase with a BET surface area of 225 m 2 /g.
- the seeds in the reaction mixture were grown by a simultaneous addition of ferrous chloride and aqueous ammonia at a pH of 4 to yield 17O g product from 60 g seeds. At that point the colour values were slightly redder than the standard Ferroxide 212. X-ray diffraction showed the sample was almost totally converted to hematite.
- This example was performed with an excess of ferrous chloride in the seed reaction mixture and gave a very good colour match and complete conversion to hematite, when using a seed which was free from goethite.
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Abstract
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PCT/EP2008/051896 WO2009100767A1 (en) | 2008-02-15 | 2008-02-15 | Process for producing red iron oxide |
US12/672,455 US8206681B2 (en) | 2008-02-15 | 2008-02-15 | Process for producing red iron oxide |
EP08709045A EP2240410A1 (en) | 2008-02-15 | 2008-02-15 | Process for producing red iron oxide |
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PCT/EP2008/051896 WO2009100767A1 (en) | 2008-02-15 | 2008-02-15 | Process for producing red iron oxide |
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Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
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WO2013045608A1 (en) | 2011-09-30 | 2013-04-04 | Lanxess Deutschland Gmbh | Improved method for producing finely divided haematite and for producing iron oxide red pigments |
WO2016034694A1 (en) | 2014-09-05 | 2016-03-10 | Lanxess Deutschland Gmbh | Preparation of iron (iii) oxide pigments |
WO2016038152A1 (en) | 2014-09-11 | 2016-03-17 | Lanxess Deutschland Gmbh | Red iron-oxide pigments with improved colour values |
EP3216765A1 (en) | 2016-03-09 | 2017-09-13 | LANXESS Deutschland GmbH | Production of iron oxide red pigment |
EP3216764A1 (en) | 2016-03-09 | 2017-09-13 | LANXESS Deutschland GmbH | Production of iron oxide red pigments |
EP3219763A1 (en) | 2016-03-16 | 2017-09-20 | LANXESS Deutschland GmbH | Use of iron oxide red pigments in aqueous preparations |
EP3597602A1 (en) | 2018-07-18 | 2020-01-22 | LANXESS Deutschland GmbH | Hematite pigments |
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RU2543189C2 (en) * | 2013-04-30 | 2015-02-27 | Общество с ограниченной ответственностью "Научно исследовательский институт пигментных материалов с опытным производством" (ООО "НИИ ПМ") | Iron oxide pigment and method for production thereof |
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DK3189010T3 (en) | 2014-09-05 | 2019-08-26 | Lanxess Deutschland Gmbh | PREPARATION OF RED IRON OXID PIGMENT |
CN108640162B (en) * | 2018-07-10 | 2024-01-09 | 河南省睿博环境工程技术有限公司 | Alkali circulation iron-containing solid waste iron oxide pigment production equipment system |
CN108516591A (en) * | 2018-07-16 | 2018-09-11 | 太原理工大学 | A kind of bigger serface FeOOH desulfurizing agent and preparation method thereof |
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CN113292103A (en) * | 2021-05-25 | 2021-08-24 | 永兴朗丰色料实业有限公司 | Method for producing nano iron oxide red by utilizing solid waste |
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- 2008-02-15 WO PCT/EP2008/051896 patent/WO2009100767A1/en active Application Filing
- 2008-02-15 EP EP08709045A patent/EP2240410A1/en not_active Ceased
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FR1519503A (en) * | 1963-06-26 | 1968-04-05 | Bayer Ag | Method for preparing variety of hydrated iron oxide |
EP0040722A1 (en) * | 1980-05-23 | 1981-12-02 | BASF Aktiengesellschaft | Process for the preparation of synthetic lepidocrocite |
DE3700943A1 (en) * | 1986-01-17 | 1987-07-23 | Showa Denko Kk | METHOD FOR PRODUCING LEPIDOCROKITE |
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Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
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WO2013045608A1 (en) | 2011-09-30 | 2013-04-04 | Lanxess Deutschland Gmbh | Improved method for producing finely divided haematite and for producing iron oxide red pigments |
WO2016034694A1 (en) | 2014-09-05 | 2016-03-10 | Lanxess Deutschland Gmbh | Preparation of iron (iii) oxide pigments |
WO2016038152A1 (en) | 2014-09-11 | 2016-03-17 | Lanxess Deutschland Gmbh | Red iron-oxide pigments with improved colour values |
WO2017153444A1 (en) | 2016-03-09 | 2017-09-14 | Lanxess Deutschland Gmbh | Preparation of red iron oxide pigment |
EP3216764A1 (en) | 2016-03-09 | 2017-09-13 | LANXESS Deutschland GmbH | Production of iron oxide red pigments |
WO2017153368A1 (en) | 2016-03-09 | 2017-09-14 | Lanxess Deutschland Gmbh | Preparation of red iron oxide pigment |
EP3216765A1 (en) | 2016-03-09 | 2017-09-13 | LANXESS Deutschland GmbH | Production of iron oxide red pigment |
EP3539928A1 (en) | 2016-03-09 | 2019-09-18 | LANXESS Deutschland GmbH | Preparation of iron oxide red pigment |
EP3219763A1 (en) | 2016-03-16 | 2017-09-20 | LANXESS Deutschland GmbH | Use of iron oxide red pigments in aqueous preparations |
EP3597602A1 (en) | 2018-07-18 | 2020-01-22 | LANXESS Deutschland GmbH | Hematite pigments |
WO2020016147A1 (en) | 2018-07-18 | 2020-01-23 | Lanxess Deutschland Gmbh | Hematite pigments |
JP2021532250A (en) * | 2018-07-18 | 2021-11-25 | ランクセス・ドイチュランド・ゲーエムベーハー | Hematite pigment |
JP7239694B2 (en) | 2018-07-18 | 2023-03-14 | ランクセス・ドイチュランド・ゲーエムベーハー | hematite pigment |
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US20110076224A1 (en) | 2011-03-31 |
US8206681B2 (en) | 2012-06-26 |
EP2240410A1 (en) | 2010-10-20 |
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