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WO1999035083A1 - Procede de production d'une suspension homogene et stable composee de produits initiaux oxydes - Google Patents

Procede de production d'une suspension homogene et stable composee de produits initiaux oxydes Download PDF

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Publication number
WO1999035083A1
WO1999035083A1 PCT/EP1998/007644 EP9807644W WO9935083A1 WO 1999035083 A1 WO1999035083 A1 WO 1999035083A1 EP 9807644 W EP9807644 W EP 9807644W WO 9935083 A1 WO9935083 A1 WO 9935083A1
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WO
WIPO (PCT)
Prior art keywords
suspension
water
range
dispersed
polymers
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.)
Ceased
Application number
PCT/EP1998/007644
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German (de)
English (en)
Inventor
Günther RIEDEL
Frank Willems
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.)
Aventis Research and Technologies GmbH and Co KG
Original Assignee
Aventis Research and Technologies GmbH and Co KG
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 Aventis Research and Technologies GmbH and Co KG filed Critical Aventis Research and Technologies GmbH and Co KG
Publication of WO1999035083A1 publication Critical patent/WO1999035083A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N60/00—Superconducting devices
    • H10N60/01—Manufacture or treatment
    • H10N60/0268—Manufacture or treatment of devices comprising copper oxide
    • H10N60/0772—Processes including the use of non-gaseous precursors
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
    • C01B13/14—Methods for preparing oxides or hydroxides in general
    • C01B13/145—After-treatment of oxides or hydroxides, e.g. pulverising, drying, decreasing the acidity
    • 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
    • C09K23/00—Use of substances as emulsifying, wetting, dispersing, or foam-producing agents
    • 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
    • C09K23/00—Use of substances as emulsifying, wetting, dispersing, or foam-producing agents
    • C09K23/017—Mixtures of compounds
    • 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
    • C09K23/00—Use of substances as emulsifying, wetting, dispersing, or foam-producing agents
    • C09K23/017—Mixtures of compounds
    • C09K23/018—Mixtures of two or more different organic oxygen-containing compounds
    • 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
    • C01P2006/22—Rheological behaviour as dispersion, e.g. viscosity, sedimentation stability
    • 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
    • C09K23/00—Use of substances as emulsifying, wetting, dispersing, or foam-producing agents
    • C09K23/34—Higher-molecular-weight carboxylic acid esters

Definitions

  • the invention relates to a method for producing a homogeneous and stable mixture of several inorganic solids by dispersing these substances in water.
  • the resulting suspension is subsequently dried and then further processed so that a high-temperature superconducting mixed oxide consisting of the elements of these substances and oxygen is formed.
  • the invention was based on the object of a method for producing a homogeneous, stable in terms of rheological properties and for the Spray drying to produce a suitable aqueous suspension in which the inorganic raw materials are dispersed according to the later chemical target composition.
  • the object is achieved with a method for producing a homogeneous
  • lanthanides including yttrium are particularly suitable, and particularly preferred among these are yttrium, lanthanum, cerium, neodymium, samarium, ytterbium and luthetium.
  • This is used to produce a well-dispersed, homogeneous, long-term stable slip suitable for spray drying.
  • the hydrolysis properties, the surface charges of the products and the control as well as the setting of a narrow pH value range of the suspension must be taken into account.
  • a combination of electrostatic and static stabilization of the suspension is preferably selected.
  • the electrostatic stabilization is based on the principle that the electrical charge present on the solid surface is identified and modified in such a way that sufficiently high and similar charges are present, which thus lead to the repulsion of the solid particles. This means that the existing agglomerates caused by Van der Waals forces are eliminated and homogeneous mixing of different raw material components can take place.
  • the surface charges are modified by using anionic surfactants as dispersants in the case of negative charges, which increase the amount of charges and thus lead to an improvement in particle repulsion. Positively charged material components are reloaded with the appropriate amount of surfactant before mixing with negatively charged substances.
  • a steric (spatial) stabilizing effect is achieved by additionally adding and incorporating polymers with chain lengths of> 2000, preferably> 3000 monomer units between the solid particles .
  • water-soluble substances which do not decompose in the pH range from 1.5 to 5 or in the preferred range from 2.5 to 4.5 can preferably flocculate or strongly thicken out of the solution, such as polyglycols, for example.
  • Polyoxazolines, polyester urethane, polyvinyl alcohol and cellulose ether can be used.
  • a pH value which is favorable for the dispersion behavior is set in the range from 1.5 to 5, preferably in the range from 2.5 to 4.5, at which the inorganic components of the batch are insoluble or only slightly soluble in water are. This avoids working in the area of the isoelectric points, where dispersion is difficult or impossible due to the absence of repulsive particle charges.
  • a polymer with a number of monomer units of at least 2000, preferably at least 3000 is attached between the solid particles, the particles are kept spatially at a distance, and steric stabilization also takes place.
  • steric stabilization ensures an even more homogeneous distribution of the different cations and long-term stabilization of the suspension despite the solid components, which tend to hydrolysis. Without steric stabilization, the effect of the dispersants or surfactants could decrease due to the hydrolysis.
  • the influencing and control of the pH value is also of particular importance for setting the slip viscosity required for spray drying and its constancy over time.
  • the pH of the various components of the superconductor precursor is different and is subject to a different change over time due to hydrolysis when introduced into water.
  • Table 1 contains this information for the raw material components of a BiPbSrCaCu oxide superconductor. It follows from this that the pH is very strong, in particular due to the relatively high proportion of Bi in these substances influenced and shifted towards lower values. All other components, in particular Ca oxalate, but also bi-hydroxide act in the opposite direction.
  • FIGS. 1 to 3 show the viscosities ( ⁇ ) of the suspensions as a function of the shear rate gradient (D), measured with a Rotovisko RV 20 from Haake. Due to the deviating from the spherical shape
  • Geometry of the solid particles results in the strong increase in viscosity for most non-spherical inorganic powders at very low shear forces or without any shear, which is referred to as the structural viscosity.
  • the processing process of the suspensions is characterized by constant movement of the suspension by stirring or conveying by means of pumps or atomizers, so that good processing properties are available at viscosities ⁇ ⁇ 100 mPa s at shear rates> 100 1 / s.
  • Example 1 corresponds to a substitution of 12.5% of the bi-oxalate by bi-hydrate, as a result of which the pH was in the range from 3 to 4, which is particularly preferred, both immediately after preparation of the suspension and after storage for 24 hours.
  • Example 2 describes the production of a lead-free material, with 15% of the bi-oxalate being replaced by the equivalent amount of bi-hydroxide.
  • the pH value can be adjusted by adding small amounts of an organic acid, e.g. Oxalic acid to lower values or by adding hydroxides such as e.g. Ammonium hydroxide to be corrected to higher values.
  • an organic acid e.g. Oxalic acid
  • hydroxides such as e.g. Ammonium hydroxide
  • Comparative Example 3 describes an approach which contained no Bi (OH) 3 for pH correction and no polymer for steric stabilization.
  • the too low pH of approx. 2 was outside the range required for liquefaction and slip stabilization, where the solution of alkaline earth metal oxalates and copper oxalate must also be expected.
  • Comparative Example 4 a batch was weighed which, after substitution of 50% of Bi 2 (C 2 0 4 ) 3, contained an excessively high proportion of Bi (OH) 3 and thus had pH values> 5 after storage for more than 3 h . At pH values> 5, water-soluble Cu complex compounds can form under the given conditions after a relatively short time. Accordingly, under the above-mentioned conditions no slip which is stable over the long term with regard to viscosity constancy can be produced.
  • Example 1 The following raw materials were weighed out for a 1 kg batch: 304 g Bi 2 (C 2 0 4 ) 3 ; 30 g Bi (OH) 3 ; 51 g Pb (C 2 0 4 ); 220 g Sr (C 2 0 4 ); 145 g Ca (C 2 0 4 ); 250 g Cu (C 2 0 4 ).
  • a pH of 3 to 4 is set by the amount and type of raw materials selected.
  • the raw materials were stirred into 1 liter of deionized water. After one hour, 10 g of ammonium polyacrylate solution with 25% active substance content were added as a dispersing agent with further stirring. This was followed by homogenization for about 1 minute using an agitator operating on the rotor-stator principle at a peripheral speed of approximately 20 m / s.
  • FIG. 1 shows the slip viscosity ⁇ as a function of the shear rate D after immediate measurement (V28) and after 1 h (V28-1), 3 h (V28-2) and 24 h (V28-3).
  • these suspensions are considered to be sprayable, taking into account the time effect, and can be spray dried with a spray dryer that works with a two-substance nozzle.
  • the suspension was produced according to Example 1.
  • the suspension was produced according to Example 1, but without the addition of polyethylene glycol for steric stabilization.
  • the suspension contained no polymer for steric stabilization (ie no addition of polyethylene glycol) and was otherwise prepared as described in Example 1. After all components had been introduced, the pH was initially 4.8 and increased to 5.2 after 3 h and to 5.6 after 24 h.
  • the combination of pH adjustment e.g. by combining oxalate and hydrate additives
  • selection of the type and amount of dispersant and addition of another polymer made it possible to solve the problem from a five-component system of oxide precursors that tended to hydrolyze to produce a long-term stable suspension for spray drying suitable for high-temperature superconductor materials.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Inorganic Chemistry (AREA)
  • Inorganic Compounds Of Heavy Metals (AREA)
  • Compositions Of Oxide Ceramics (AREA)

Abstract

L'invention concerne un procédé de production d'une suspension homogène pouvant être utilisée pour la production de poudres supraconductrices par voie d'oxydation. Selon ce procédé, des produits initiaux oxydes du groupe de Mg, Ca, Ba, Sr, Bi, Pb, Cu, Al, Zr, Hf, Sc, Y, TI, Pt, Ag, Hg et des éléments terres rares insolubles ou peu solubles dans l'eau sont dispersés dans l'eau. La suspension ainsi obtenue est stabilisée par voie électrostatique à un pH compris entre 1,5 et 5.
PCT/EP1998/007644 1998-01-06 1998-11-26 Procede de production d'une suspension homogene et stable composee de produits initiaux oxydes Ceased WO1999035083A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19800168.1 1998-01-06
DE19800168A DE19800168A1 (de) 1998-01-06 1998-01-06 Verfahren zur Herstellung einer homogenen und stabilen Suspension aus Oxidvorprodukten

Publications (1)

Publication Number Publication Date
WO1999035083A1 true WO1999035083A1 (fr) 1999-07-15

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ID=7854017

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1998/007644 Ceased WO1999035083A1 (fr) 1998-01-06 1998-11-26 Procede de production d'une suspension homogene et stable composee de produits initiaux oxydes

Country Status (2)

Country Link
DE (1) DE19800168A1 (fr)
WO (1) WO1999035083A1 (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001008236A1 (fr) * 1999-07-23 2001-02-01 American Superconductor Corporation Precurseur de film epais a conducteur revetu
US6436317B1 (en) 1999-05-28 2002-08-20 American Superconductor Corporation Oxide bronze compositions and textured articles manufactured in accordance therewith
US6562761B1 (en) 2000-02-09 2003-05-13 American Superconductor Corporation Coated conductor thick film precursor
US6669774B1 (en) 1999-07-23 2003-12-30 American Superconductor Corporation Methods and compositions for making a multi-layer article
US6673387B1 (en) 2000-07-14 2004-01-06 American Superconductor Corporation Control of oxide layer reaction rates
US6730410B1 (en) 1999-08-24 2004-05-04 Electronic Power Research Institute, Incorporated Surface control alloy substrates and methods of manufacture therefor
US6765151B2 (en) 1999-07-23 2004-07-20 American Superconductor Corporation Enhanced high temperature coated superconductors
US6828507B1 (en) 1999-07-23 2004-12-07 American Superconductor Corporation Enhanced high temperature coated superconductors joined at a cap layer
US6974501B1 (en) 1999-11-18 2005-12-13 American Superconductor Corporation Multi-layer articles and methods of making same
US7326434B2 (en) 2000-10-23 2008-02-05 American Superconductor Corporation Precursor solutions and methods of using same

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB929239A (en) * 1960-06-29 1963-06-19 Monsanto Chemicals Process for improving the properties of aqueous dispersions
EP0294991A2 (fr) * 1987-06-10 1988-12-14 Nippon Steel Corporation Poudre apte au frittage du type oxyde perovskite contenant un élément du groupe va et élément laminé obtenu à partir de cette poudre
WO1988010009A1 (fr) * 1987-06-09 1988-12-15 E.I. Du Pont De Nemours And Company Procede ameliore de fabrication de supraconducteurs
EP0341030A2 (fr) * 1988-05-04 1989-11-08 E.I. Du Pont De Nemours And Company Matériau supraconducteur mis en forme
EP0360550A2 (fr) * 1988-09-20 1990-03-28 Minnesota Mining And Manufacturing Company Fibres de YBa2 Cu3 O7
EP0384785A2 (fr) * 1989-02-24 1990-08-29 E.I. Du Pont De Nemours And Company Procédé pour la préparation de fibres supraconductrices à haute densité
US5244872A (en) * 1990-11-27 1993-09-14 International Superconductivity Technology Center Method of preparing Pb-Sr-Ca-Ln-Ca-O metal oxide superconductor
WO1994000385A1 (fr) * 1992-06-23 1994-01-06 The University Of Queensland OBTENTION D'OXYDES SUPRACONDUCTEURS PAR CO-PRECIPITATION A pH CONSTANT

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB929239A (en) * 1960-06-29 1963-06-19 Monsanto Chemicals Process for improving the properties of aqueous dispersions
WO1988010009A1 (fr) * 1987-06-09 1988-12-15 E.I. Du Pont De Nemours And Company Procede ameliore de fabrication de supraconducteurs
EP0294991A2 (fr) * 1987-06-10 1988-12-14 Nippon Steel Corporation Poudre apte au frittage du type oxyde perovskite contenant un élément du groupe va et élément laminé obtenu à partir de cette poudre
EP0341030A2 (fr) * 1988-05-04 1989-11-08 E.I. Du Pont De Nemours And Company Matériau supraconducteur mis en forme
EP0360550A2 (fr) * 1988-09-20 1990-03-28 Minnesota Mining And Manufacturing Company Fibres de YBa2 Cu3 O7
EP0384785A2 (fr) * 1989-02-24 1990-08-29 E.I. Du Pont De Nemours And Company Procédé pour la préparation de fibres supraconductrices à haute densité
US5244872A (en) * 1990-11-27 1993-09-14 International Superconductivity Technology Center Method of preparing Pb-Sr-Ca-Ln-Ca-O metal oxide superconductor
WO1994000385A1 (fr) * 1992-06-23 1994-01-06 The University Of Queensland OBTENTION D'OXYDES SUPRACONDUCTEURS PAR CO-PRECIPITATION A pH CONSTANT

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6436317B1 (en) 1999-05-28 2002-08-20 American Superconductor Corporation Oxide bronze compositions and textured articles manufactured in accordance therewith
WO2001008236A1 (fr) * 1999-07-23 2001-02-01 American Superconductor Corporation Precurseur de film epais a conducteur revetu
US6669774B1 (en) 1999-07-23 2003-12-30 American Superconductor Corporation Methods and compositions for making a multi-layer article
US6765151B2 (en) 1999-07-23 2004-07-20 American Superconductor Corporation Enhanced high temperature coated superconductors
US6828507B1 (en) 1999-07-23 2004-12-07 American Superconductor Corporation Enhanced high temperature coated superconductors joined at a cap layer
US6893732B1 (en) 1999-07-23 2005-05-17 American Superconductor Corporation Multi-layer articles and methods of making same
US6730410B1 (en) 1999-08-24 2004-05-04 Electronic Power Research Institute, Incorporated Surface control alloy substrates and methods of manufacture therefor
US6974501B1 (en) 1999-11-18 2005-12-13 American Superconductor Corporation Multi-layer articles and methods of making same
US6562761B1 (en) 2000-02-09 2003-05-13 American Superconductor Corporation Coated conductor thick film precursor
US6673387B1 (en) 2000-07-14 2004-01-06 American Superconductor Corporation Control of oxide layer reaction rates
US7326434B2 (en) 2000-10-23 2008-02-05 American Superconductor Corporation Precursor solutions and methods of using same
US7939126B2 (en) 2000-10-23 2011-05-10 American Superconductor Corporation Precursor solutions and methods of using same

Also Published As

Publication number Publication date
DE19800168A1 (de) 1999-07-15

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