CA2131326C - Production of cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures - Google Patents
Production of cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures Download PDFInfo
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- H01F1/346—[(TO4) 3] with T= Si, Al, Fe, Ga
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Abstract
This invention relates to a generic process for producing a refractory oxide at a temperature below the melting point of the pure refractory oxide, by the steps of heating a fully hydrated halide or a hydrated halide-oxide dried cationically homogeneous nanostructured mixture to a temperature at which a cationically homogeneous nanostructured solid state hydroxyhalide is produced. The solid state hydroxyhalide is then heated to its decomposition-temperature, at which it decomposes, by heat alone, into a cationically homogeneous nanostructured solid state oxyhalide; and performing one of the following heating steps: (i) heating the solid state oxyhalide to a solid state oxyhalide decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically homogeneous nanostructured solid state refractory oxide; or (ii) heating the solid state oxyhalide to a molten state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically homogeneous nanostructured solid state refractory oxide; or (iii) heating the solid state oxyhalide to a vapor state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically homogeneous nanostructured solid state refractory oxide.
Description
PRODUCTION OF CATIONICALLY HOMOGENEOUS
REFRACTORY OXIDES OF NANOMETER-SCALE PARTICLE SIZE
DIAMETERS AT REDUCED TEMPERATURES
Background of the Invention This invention relates to a generic and novel process, hereinafter called the Uniform Cation Distribution Process (UCDP), for producing, at reduced temperatures, cationically homogeneous nanostructured refractory metal hydroxyhalides, metal oxyhalides and metal oxides and to the novel products thereof.
More particularly, this invention relates to a process for the manufacture, from small to commercial size quantities, of refractory oxides of all compositional categories including undoped, doped, solid solution, congruent melting, incongruent melting, stoichiometric and non-stoichiometric compositions as polycrystalline, glass or three-dimensional single crystalline entities, by thermochemical reactions of hydrated homogeneous ly dispersed colloidal mixtures of halides or halide-oxides which form and decompose as precursor complexes into refrac tory oxide end products.
Prior art halide hydrolysis practiced consisted of vapor phased hydrolysis, as exemplified by the below references, or by crystallizing small, thin, stoichiometric, binary oxide single crystals from programmed temperature-cooled solutions.
The purity and quality of the resultant crystals were poor mainly because of inevitable solvent inclusions in the crys-tals and the very low acceptable crystal yields were seldom reproducible due to insufficient hydration for complete ther-mochemical hydrolysis of metal halides.
Some references describing thermohydrolytic prior art procedures for synthesizing refractory oxide compounds, are:
_. _..~.n 1. Popov, A.I.; Knudson, G.E., "Preparation and Properties of the Rare Earth Fluorides and Oxyfluorides,"J. Am.
Chem. Soc., 76, Feb. 1954, p. 3921.
REFRACTORY OXIDES OF NANOMETER-SCALE PARTICLE SIZE
DIAMETERS AT REDUCED TEMPERATURES
Background of the Invention This invention relates to a generic and novel process, hereinafter called the Uniform Cation Distribution Process (UCDP), for producing, at reduced temperatures, cationically homogeneous nanostructured refractory metal hydroxyhalides, metal oxyhalides and metal oxides and to the novel products thereof.
More particularly, this invention relates to a process for the manufacture, from small to commercial size quantities, of refractory oxides of all compositional categories including undoped, doped, solid solution, congruent melting, incongruent melting, stoichiometric and non-stoichiometric compositions as polycrystalline, glass or three-dimensional single crystalline entities, by thermochemical reactions of hydrated homogeneous ly dispersed colloidal mixtures of halides or halide-oxides which form and decompose as precursor complexes into refrac tory oxide end products.
Prior art halide hydrolysis practiced consisted of vapor phased hydrolysis, as exemplified by the below references, or by crystallizing small, thin, stoichiometric, binary oxide single crystals from programmed temperature-cooled solutions.
The purity and quality of the resultant crystals were poor mainly because of inevitable solvent inclusions in the crys-tals and the very low acceptable crystal yields were seldom reproducible due to insufficient hydration for complete ther-mochemical hydrolysis of metal halides.
Some references describing thermohydrolytic prior art procedures for synthesizing refractory oxide compounds, are:
_. _..~.n 1. Popov, A.I.; Knudson, G.E., "Preparation and Properties of the Rare Earth Fluorides and Oxyfluorides,"J. Am.
Chem. Soc., 76, Feb. 1954, p. 3921.
2. Brixner, L.H., "Ferromagnetic Material Produced From Fer-ric Oxide And Barium Halide or Strontium Halide, And Process For Making Same," U.S. Patent 3,113,109, Dec.
3, 1963.
3. Messier, D.R.; Pask, J.A., "Kinetics of High Temperature Hydrolysis of Magnesium Fluoride: II, Influence of Speci-men Geometry and Type and of Product Layers", J. Am. Cer.
Soc., Vol 48, No. 8, Sept. 1965, p. 459.
3. Messier, D.R.; Pask, J.A., "Kinetics of High Temperature Hydrolysis of Magnesium Fluoride: II, Influence of Speci-men Geometry and Type and of Product Layers", J. Am. Cer.
Soc., Vol 48, No. 8, Sept. 1965, p. 459.
4. bugger. C.O., "The Growth of Pink Magnesium Aluminate (MgA1204) Single Crystals," J. of Electrochem. Soc., Vol 113, No. 3, March 1966, p. 306.
5. bugger, C.O. , "Solution Growth of Oxidic Spinel and Other Oxide Single Crystals Following The Hydrolysis of Some Fluorides," J. of Phys. & Chem. of Solids Supplement, 1st Ed., Pergamon Press, New York, 1967, p. 493.
6. bugger, C.O., "Method For Growing Oxide Single Crystals,"
U.S. Patent 3,595,803, July 27, 1971.
U.S. Patent 3,595,803, July 27, 1971.
7. Utsunomya, T.; Hoshino, Y.; Sato, M., "Process of Hydro-lysis Reaction from YF3 to Y203 in a Humid Air at High Temperatures," Bulletin of the Tokyo Institute of Techno-logy, No. 108, 1972.
Brixner, U. S. Patent No. 3,113,109, discloses a process for the production of a ferromagnetic refractory oxide material from ferric oxide and barium halide or strontium halide, in the presence of water vapor, oxygen or a mixture thereof, at 700-1350°C. In one aspect, a molten mixture of the ferric ox-ide and a 2-3 times stoichiometric excess of the metal halide is employed as the reaction medium. In such a technique, the cation composition of the molten mixture differs from that of the oxide product, i.e., the molar ratio of the metal halide is greater in the reaction medium than its molar ratio in the refractory oxide product. Even though the product is in the form of single crystals, the product inherently is not cation-ically homogeneous because of occluded cations from the reac-tion medium. Also, although transparent single crystals were obtained, they were in the form of thin substantially two di mensional platelets (10-100 microns thick and up to 2 mm in diameter); unlike three-dimensional single crystals of this invention.
The UCDP differs from the prior art refractory oxide man-ufacturing processes in that the refractory oxides are pro-duced from a cationically homogeneous nanostructured substan-tially pure oxyhalides. The UCDP also differs in that it can produce on both large and small scales, a wide variety of nov-el and known crystalline refractory oxides of all composition-al categories from the three states of matter [solid, liquid (molten) and vapor states].
While the UCDP is a generic process for producing pre cisely high reproducible yields of all of the refractory oxide compositional categories, there is some scientific uncertainty as to the actual precursor (intermediate) reactions that occur in thermochemically converting a hydrated metal halide to a refractory oxide end product; hydroxyhalide and oxyhalide com plexes are reported in the literature. In addition, it is not certain if all hydrated metal halides convert to both interme-diate complexes. In this invention, however, it is assumed that all hydrated metal halides are thermochemically converted to both hydroxyhalide and oxyhalide complexes only, and the hydroxyhalide and the oxyhalide complexes are considered to be low temperature (s 500°C) and high temperature complexes, re-spectively. A chemical complex composition of this invention consists of one or more metal halides bonded to oxygen, hy-droxyl groups or both. Thus, hydroxyhalides and oxyhalides are chemical complexes which may exhibit an overall excess electric charge(s).
In the context of this invention, the term "hydrolysis"
as used herein is the chemical reaction of a substance with liquid water or its ions.
The use of liquid water as a reactant is a substantial improvement over the prior art technique of using indetermi-nate moist gases or waters of crystallization as the water-source reactant. The halides used in the UCDP are not only fully hydrated, which ensures complete hydrolytic reactions, but also the liquid water, of appropriate pH, is a homogeneous reactant-mixing medium. The combined simultaneous chemical exothermic halide-hydration reaction and homogeneous physical water-mixing produces a homogeneously dispersed colloidal re-actant mixture from which all the UCDP precursors and refrac-tory oxides are produced.
The term "refractory oxide" is used herein in its conven-tional sense . It is a metal oxide, usually of one or more met-al cations and which has a fusion point, i.e. , it becomes mol-ten upon heating. In this invention, the Chemical Periodic Ta-ble metals of Groups IA - VA, IB - VIIB and VIII, the lantha-nides, and the actinides, thorium and uranium can be used to produce metal halides and oxides. A cation is a positively charged ion.
The term "cationically homogeneous" means that the re-fractory oxide is substantially free of occluded extraneous cations.
A refractory oxide is called either a nanostructured or nanophased composition when its colloidal particle size dia-meters are less than about a hundred nanometers. These nano phased materials can be used to produce new classes of ceram ics and ceramic composites which demonstrate enhanced magnet ic, electronic and mechanical properties and can lead to ad vanced materials, engineering breakthroughs and new techno logies.
The term "substantially pure" as used herein means the actual cationic composition thereof differs by no more than about 5 wt% from theoretical based upon chemical analysis, preferably less than 2 wt%, and most preferably, e.g., in the .~"
t ' _..
case of refractory oxides to be used in a laser or a superconductor, 0.25 wt~ or less.
Objects of the Invention A primary object of this invention is to provide a novel, generic and highly reliable process which, on a commercial scale, can produce refractory oxides that are cationically homogeneous, nanostructured and substantially pure.
Another object is the provision of a process for the manufacture of such refractory oxides at temperatures ranging from 100°C to 1500°C below their pure melting points.
Yet another object is the manufacture of novel refractory oxide compositions.
A further object of this invention is to provide a process which markedly reduces or eliminates the prior art disadvantages attendant to refractory oxide materials pre-paration.
Still further objects of advantages and features of this invention will become apparent upon consideration of the following detailed description thereof.
Suamo~ary of the Invention In a process aspect, this invention relates to a pro cess which comprises producing a cationically homogeneous nanostructured substantially pure metal oxyhalide which is thermochemically decomposes, by heat alone, into its refractory oxide.
In a preferred process aspect, this invention relates to a generic process for producing a refractory oxide which comprises (a) reacting and dispersal-blending liquid water with: (i) at least one metal halide reactant; (ii)at least one metal halide reactant and at least one metal oxide reactant; (iii) at least one metal oxide reactant and a hydrogen halide composition, to produce fully - hydrated, cation-{ E3009570.DOC;3 } E3009570.DOC;1 }
ically-homogeneous nanostructured colloidal mixture; (b) heating the colloidal mixture to produce a solid state metal hydroxyhalide; (c) further heating the metal hy-droxyhalide to a higher temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state metal oxyhalide; and performing one of the following heating steps: (i) heating the metal oxyhalide to a solid state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide; (ii) heating the metal oxyhalide to a molten state decomposition-temperature at which it chemi-cally decomposes, by heat alone, into a cationically-homo-geneous nanostructured solid state refractory oxide;
(iii) heating the metal oxyhalide to a vapor state decom-position-temperature at Which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide.
In a composition aspect, this invention relates to cationically homogeneous nanostructured refractory oxides, most of which are transparent and many of which have one or both of electrostatic and magnetic properties.
In another composition aspect, this invention relates to chemically novel refractory oxides.
In yet another composition aspect, this invention re-lates to the hydroxyhalide and oxyhalide precursors of the refractory oxides of this invention.
Detailed Description of the Invention The UCDP is an extraordinary and powerful manufacturing process because of its generic capability to manufacture virtually any refractory oxide that can be produced at atmospheric pressure.
Additionally, UCDP's novel products' properties /E3009570.DOC;3}E3009570.DOC;1 }
enable the products to be used in all refractory oxide pro-cedures and applications such as sensors, filters, photonics, wave-guides, high strength near-net-shape structures, super-conductors, insulators, catalysts, films, fibers nuclear waste management, etc.
As illustrated in the examples below, the number of dif-ferent rations and their concentrations in the end products can vary widely. The purity, quality and homogeneity of the end products are very high and precisely reproducible.
In a preferred aspect, the refractory oxides of this in-vention are produced from a metal oxyhalide precursor thereto selected from the group consisting of:
a) Bat_(p+S+o.5x>R0.67pDsUxMg1-yD~'lto-(z+wZ~'TzQ0.75w~17,-0.5 G9 DS=Ca, Sr, Pb; G=F, cl; Q=Si, ~e;
J=Cr, Ga, Ti, Mn, V, Fe, Co; U=Na, K;
Dy=Co, Cu, Ge, Ni, Zn; R=Y, lanthanides;
gs33.7; Osps0.6; Osssl.0;
Osxsl.2; Osysl; Oszs0.6; Osws7.5;
b ) Baz-pNat _ (x)KxRO. b7pNb5-yTayOt 5-0.5gG
G = F, C1; R = Y, Lantghanides gs29.7; Osps0.6; Osxsl.0; Osys5.0;
c) Srt-(x+Zp+z>BGxLTpR~~Jo. 7zNb2-yTay06-o.5 Gs C~; U = Na, f~;
J = Cr, Fe; R = Y, Lanthanides;
gsl.7; Osps0.18; Osxsl; Osys2; Oszs0.18;
d) Ba _ D Ti _ J Zr O _ G
t x D 1 (yr '75zP~ z Ca 3 0.5g 9 $ ~ 1J ~
G = F, C1; J = Fe, Cr gs5.7; Osxsl; Osysl; Oszs0.l;
a) KTat,(x+0 6yNbx'7y~3-0.5gG
G = F, C~; J = Cr, ~'e;
gs5.7; Osxsl; Osys0.l;
f ) Llt-(x+Z+d)D0.5xD0.5d'T0.33zTa1~by~3-0.5gG
Dx = Ni, Co, Fe, Mg; G = ~, C1;
Dd= Ni, Co, Cu, Zn; J = Cr, Fe; G = F, Cl Osds0.12; gs5.7; Osxsl; Osysl; Oszs0.4;
g) Mgt; (x+y+z)Dz'T0.67yR0.67x~t-0.5 Gg D = Ni, Co, Fe, Cu, Ge, ~Ln;
w~
J = Cr, Fe, Ti; G = F, C1; R = Lanthanides gsl.7; Osxs0.005; Osysl; Oszsl;
h) Mg1-zDzAl2-(x+Y>RxJ 04-o.5gG9 G = F, C1; D = Co, Nvi, Cu, Zn, Ge J = Co, Cr, Fe, Mn, Ti, V; R = Lanthanides gs7.7; Osxsl; Osys2; Oszsl;
i ) Dbz-zDBa1-x)ca xNb GvTavO~ 5-C ~9G9 - . , , gs29.7; Osxsl, Osys5, Oszs2;
] ) Y2-(x+d)Rx'Td~3-0.596 G = F, Cl; R = Lant~hanides;
J = Cr, Ga, Ti, Fe, Al, V, Co, Ni, Cu, Mn;
Osds0.15; gs5.7; Osxs2;
k) AlZ-(x+y+W>Rx'TyQ0.75w~3-0.5 Gg J = Cr, Ga, Ti, Fe, V, Lo, Mn;
G=F, Cl; Q= Si, Ge, Sn; R = Lanthanides;
gs5.7; Osxs0.12; Osys0.12; Oswsl.8;
1 ) Y3-xRxAl (y+W)JYQ0.75W~12-0.5g~,'g G = F, C~; R = Lanthanides J = Cr, Ga, Ti, Fe, V, Co, Mn;
Q = Si, Ge gs23.7; Osws5; Osxs3; Osys0.5;
m) Y3-xR Fe5 JYO~2_0 5 Gs G = F, C~; ~ = Lansthanides J = Cr, A1, Ga, Co, Mn;
gs23.7; Osxs3; Osys5; and where "U", "D", "R", "J", and "Q" are one or more: univalent, divalent, rare-earth, trivalent and tetravalent cations, re-spectively; and, "G" is one or more halogen ions; and, each lower-case letter of the formulae denotes a variable numerical value of the atomic ratio of that chemical element in the com-position. The preferred refractory oxides of this invention otherwise correspond to the above formulae without the G9 ele-ment.
UCDP compositions are manufactured by the below thermo-chemical Reactions I-IV. For example, in the case of yttrium oxide (Y203), the overall reaction equation is:
Brixner, U. S. Patent No. 3,113,109, discloses a process for the production of a ferromagnetic refractory oxide material from ferric oxide and barium halide or strontium halide, in the presence of water vapor, oxygen or a mixture thereof, at 700-1350°C. In one aspect, a molten mixture of the ferric ox-ide and a 2-3 times stoichiometric excess of the metal halide is employed as the reaction medium. In such a technique, the cation composition of the molten mixture differs from that of the oxide product, i.e., the molar ratio of the metal halide is greater in the reaction medium than its molar ratio in the refractory oxide product. Even though the product is in the form of single crystals, the product inherently is not cation-ically homogeneous because of occluded cations from the reac-tion medium. Also, although transparent single crystals were obtained, they were in the form of thin substantially two di mensional platelets (10-100 microns thick and up to 2 mm in diameter); unlike three-dimensional single crystals of this invention.
The UCDP differs from the prior art refractory oxide man-ufacturing processes in that the refractory oxides are pro-duced from a cationically homogeneous nanostructured substan-tially pure oxyhalides. The UCDP also differs in that it can produce on both large and small scales, a wide variety of nov-el and known crystalline refractory oxides of all composition-al categories from the three states of matter [solid, liquid (molten) and vapor states].
While the UCDP is a generic process for producing pre cisely high reproducible yields of all of the refractory oxide compositional categories, there is some scientific uncertainty as to the actual precursor (intermediate) reactions that occur in thermochemically converting a hydrated metal halide to a refractory oxide end product; hydroxyhalide and oxyhalide com plexes are reported in the literature. In addition, it is not certain if all hydrated metal halides convert to both interme-diate complexes. In this invention, however, it is assumed that all hydrated metal halides are thermochemically converted to both hydroxyhalide and oxyhalide complexes only, and the hydroxyhalide and the oxyhalide complexes are considered to be low temperature (s 500°C) and high temperature complexes, re-spectively. A chemical complex composition of this invention consists of one or more metal halides bonded to oxygen, hy-droxyl groups or both. Thus, hydroxyhalides and oxyhalides are chemical complexes which may exhibit an overall excess electric charge(s).
In the context of this invention, the term "hydrolysis"
as used herein is the chemical reaction of a substance with liquid water or its ions.
The use of liquid water as a reactant is a substantial improvement over the prior art technique of using indetermi-nate moist gases or waters of crystallization as the water-source reactant. The halides used in the UCDP are not only fully hydrated, which ensures complete hydrolytic reactions, but also the liquid water, of appropriate pH, is a homogeneous reactant-mixing medium. The combined simultaneous chemical exothermic halide-hydration reaction and homogeneous physical water-mixing produces a homogeneously dispersed colloidal re-actant mixture from which all the UCDP precursors and refrac-tory oxides are produced.
The term "refractory oxide" is used herein in its conven-tional sense . It is a metal oxide, usually of one or more met-al cations and which has a fusion point, i.e. , it becomes mol-ten upon heating. In this invention, the Chemical Periodic Ta-ble metals of Groups IA - VA, IB - VIIB and VIII, the lantha-nides, and the actinides, thorium and uranium can be used to produce metal halides and oxides. A cation is a positively charged ion.
The term "cationically homogeneous" means that the re-fractory oxide is substantially free of occluded extraneous cations.
A refractory oxide is called either a nanostructured or nanophased composition when its colloidal particle size dia-meters are less than about a hundred nanometers. These nano phased materials can be used to produce new classes of ceram ics and ceramic composites which demonstrate enhanced magnet ic, electronic and mechanical properties and can lead to ad vanced materials, engineering breakthroughs and new techno logies.
The term "substantially pure" as used herein means the actual cationic composition thereof differs by no more than about 5 wt% from theoretical based upon chemical analysis, preferably less than 2 wt%, and most preferably, e.g., in the .~"
t ' _..
case of refractory oxides to be used in a laser or a superconductor, 0.25 wt~ or less.
Objects of the Invention A primary object of this invention is to provide a novel, generic and highly reliable process which, on a commercial scale, can produce refractory oxides that are cationically homogeneous, nanostructured and substantially pure.
Another object is the provision of a process for the manufacture of such refractory oxides at temperatures ranging from 100°C to 1500°C below their pure melting points.
Yet another object is the manufacture of novel refractory oxide compositions.
A further object of this invention is to provide a process which markedly reduces or eliminates the prior art disadvantages attendant to refractory oxide materials pre-paration.
Still further objects of advantages and features of this invention will become apparent upon consideration of the following detailed description thereof.
Suamo~ary of the Invention In a process aspect, this invention relates to a pro cess which comprises producing a cationically homogeneous nanostructured substantially pure metal oxyhalide which is thermochemically decomposes, by heat alone, into its refractory oxide.
In a preferred process aspect, this invention relates to a generic process for producing a refractory oxide which comprises (a) reacting and dispersal-blending liquid water with: (i) at least one metal halide reactant; (ii)at least one metal halide reactant and at least one metal oxide reactant; (iii) at least one metal oxide reactant and a hydrogen halide composition, to produce fully - hydrated, cation-{ E3009570.DOC;3 } E3009570.DOC;1 }
ically-homogeneous nanostructured colloidal mixture; (b) heating the colloidal mixture to produce a solid state metal hydroxyhalide; (c) further heating the metal hy-droxyhalide to a higher temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state metal oxyhalide; and performing one of the following heating steps: (i) heating the metal oxyhalide to a solid state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide; (ii) heating the metal oxyhalide to a molten state decomposition-temperature at which it chemi-cally decomposes, by heat alone, into a cationically-homo-geneous nanostructured solid state refractory oxide;
(iii) heating the metal oxyhalide to a vapor state decom-position-temperature at Which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide.
In a composition aspect, this invention relates to cationically homogeneous nanostructured refractory oxides, most of which are transparent and many of which have one or both of electrostatic and magnetic properties.
In another composition aspect, this invention relates to chemically novel refractory oxides.
In yet another composition aspect, this invention re-lates to the hydroxyhalide and oxyhalide precursors of the refractory oxides of this invention.
Detailed Description of the Invention The UCDP is an extraordinary and powerful manufacturing process because of its generic capability to manufacture virtually any refractory oxide that can be produced at atmospheric pressure.
Additionally, UCDP's novel products' properties /E3009570.DOC;3}E3009570.DOC;1 }
enable the products to be used in all refractory oxide pro-cedures and applications such as sensors, filters, photonics, wave-guides, high strength near-net-shape structures, super-conductors, insulators, catalysts, films, fibers nuclear waste management, etc.
As illustrated in the examples below, the number of dif-ferent rations and their concentrations in the end products can vary widely. The purity, quality and homogeneity of the end products are very high and precisely reproducible.
In a preferred aspect, the refractory oxides of this in-vention are produced from a metal oxyhalide precursor thereto selected from the group consisting of:
a) Bat_(p+S+o.5x>R0.67pDsUxMg1-yD~'lto-(z+wZ~'TzQ0.75w~17,-0.5 G9 DS=Ca, Sr, Pb; G=F, cl; Q=Si, ~e;
J=Cr, Ga, Ti, Mn, V, Fe, Co; U=Na, K;
Dy=Co, Cu, Ge, Ni, Zn; R=Y, lanthanides;
gs33.7; Osps0.6; Osssl.0;
Osxsl.2; Osysl; Oszs0.6; Osws7.5;
b ) Baz-pNat _ (x)KxRO. b7pNb5-yTayOt 5-0.5gG
G = F, C1; R = Y, Lantghanides gs29.7; Osps0.6; Osxsl.0; Osys5.0;
c) Srt-(x+Zp+z>BGxLTpR~~Jo. 7zNb2-yTay06-o.5 Gs C~; U = Na, f~;
J = Cr, Fe; R = Y, Lanthanides;
gsl.7; Osps0.18; Osxsl; Osys2; Oszs0.18;
d) Ba _ D Ti _ J Zr O _ G
t x D 1 (yr '75zP~ z Ca 3 0.5g 9 $ ~ 1J ~
G = F, C1; J = Fe, Cr gs5.7; Osxsl; Osysl; Oszs0.l;
a) KTat,(x+0 6yNbx'7y~3-0.5gG
G = F, C~; J = Cr, ~'e;
gs5.7; Osxsl; Osys0.l;
f ) Llt-(x+Z+d)D0.5xD0.5d'T0.33zTa1~by~3-0.5gG
Dx = Ni, Co, Fe, Mg; G = ~, C1;
Dd= Ni, Co, Cu, Zn; J = Cr, Fe; G = F, Cl Osds0.12; gs5.7; Osxsl; Osysl; Oszs0.4;
g) Mgt; (x+y+z)Dz'T0.67yR0.67x~t-0.5 Gg D = Ni, Co, Fe, Cu, Ge, ~Ln;
w~
J = Cr, Fe, Ti; G = F, C1; R = Lanthanides gsl.7; Osxs0.005; Osysl; Oszsl;
h) Mg1-zDzAl2-(x+Y>RxJ 04-o.5gG9 G = F, C1; D = Co, Nvi, Cu, Zn, Ge J = Co, Cr, Fe, Mn, Ti, V; R = Lanthanides gs7.7; Osxsl; Osys2; Oszsl;
i ) Dbz-zDBa1-x)ca xNb GvTavO~ 5-C ~9G9 - . , , gs29.7; Osxsl, Osys5, Oszs2;
] ) Y2-(x+d)Rx'Td~3-0.596 G = F, Cl; R = Lant~hanides;
J = Cr, Ga, Ti, Fe, Al, V, Co, Ni, Cu, Mn;
Osds0.15; gs5.7; Osxs2;
k) AlZ-(x+y+W>Rx'TyQ0.75w~3-0.5 Gg J = Cr, Ga, Ti, Fe, V, Lo, Mn;
G=F, Cl; Q= Si, Ge, Sn; R = Lanthanides;
gs5.7; Osxs0.12; Osys0.12; Oswsl.8;
1 ) Y3-xRxAl (y+W)JYQ0.75W~12-0.5g~,'g G = F, C~; R = Lanthanides J = Cr, Ga, Ti, Fe, V, Co, Mn;
Q = Si, Ge gs23.7; Osws5; Osxs3; Osys0.5;
m) Y3-xR Fe5 JYO~2_0 5 Gs G = F, C~; ~ = Lansthanides J = Cr, A1, Ga, Co, Mn;
gs23.7; Osxs3; Osys5; and where "U", "D", "R", "J", and "Q" are one or more: univalent, divalent, rare-earth, trivalent and tetravalent cations, re-spectively; and, "G" is one or more halogen ions; and, each lower-case letter of the formulae denotes a variable numerical value of the atomic ratio of that chemical element in the com-position. The preferred refractory oxides of this invention otherwise correspond to the above formulae without the G9 ele-ment.
UCDP compositions are manufactured by the below thermo-chemical Reactions I-IV. For example, in the case of yttrium oxide (Y203), the overall reaction equation is:
8 ,..~ ;
2YF3 (p) + 3Hz0 (1) --> Y203 (c) + 6HF (g) The hydrogen fluoride product weight percent loss is ca. 350.
Reaction I: YF3 hydration (chemisorption ca.20°C to ca.
150°C) 2YF3 (p) + 3HZ0 (1) --> 2 [YF3~ 1 . 5H20] (c) + heat .
Reaction II: Thermochemical halide hydrolytic reactions and shifting chemical equilibria cause the forma-tion of a solid state hydroxyfluoride complex from ca. 150°C to ca. 500°C.
2 [YF3~ 1 . 5H20] (c) --> YZ (OH) 3F3 (c) + 3HF (g) Reaction IIA: Oxide-hydrogen halide hydrolytic group alter-nate reaction to Reactions I & II.
YZ03+ 3 HF - - > YZ ( OH ) 3F3 Reaction III: Increasing temperature (>500°C), shifting chemical equilibria and solid state activated hydroxyfluoride decomposition causes the for-mation of a solid state oxyfluoride complex at ca. 1000°C.
Y2 (OH) 3F3 (c) --> YZ03F33- (c) + 3H+ (g) Reaction IIIA: Solid state activated oxyhalide complex decom-position to refractory end product at ca.
1100°C & 80 hrs.
y203F33 ( c ) - - > yZp3 ( c ) + 3 F ( g ) Reaction IV: Molten or vapor state isothermal Y203F33- (m, g) decomposition temperature at ca. 1550°C or programmed cooling to 1250°C over eight hours produces transparent YZ03 crystals.
3O Y203F33~ (m, g) cooling to form Yz03 (c) + 3F- (g) In the above equations, p=powder; 1=liquid; g=gas; c=crys-talline; m=molten; and --> = reaction direction and heating.
The proposed Reactions I-IV are assumed to be molecular complex reactions that proceed by shifting chemical equilibria irreversibly to the right to produce refractory oxides.
2YF3 (p) + 3Hz0 (1) --> Y203 (c) + 6HF (g) The hydrogen fluoride product weight percent loss is ca. 350.
Reaction I: YF3 hydration (chemisorption ca.20°C to ca.
150°C) 2YF3 (p) + 3HZ0 (1) --> 2 [YF3~ 1 . 5H20] (c) + heat .
Reaction II: Thermochemical halide hydrolytic reactions and shifting chemical equilibria cause the forma-tion of a solid state hydroxyfluoride complex from ca. 150°C to ca. 500°C.
2 [YF3~ 1 . 5H20] (c) --> YZ (OH) 3F3 (c) + 3HF (g) Reaction IIA: Oxide-hydrogen halide hydrolytic group alter-nate reaction to Reactions I & II.
YZ03+ 3 HF - - > YZ ( OH ) 3F3 Reaction III: Increasing temperature (>500°C), shifting chemical equilibria and solid state activated hydroxyfluoride decomposition causes the for-mation of a solid state oxyfluoride complex at ca. 1000°C.
Y2 (OH) 3F3 (c) --> YZ03F33- (c) + 3H+ (g) Reaction IIIA: Solid state activated oxyhalide complex decom-position to refractory end product at ca.
1100°C & 80 hrs.
y203F33 ( c ) - - > yZp3 ( c ) + 3 F ( g ) Reaction IV: Molten or vapor state isothermal Y203F33- (m, g) decomposition temperature at ca. 1550°C or programmed cooling to 1250°C over eight hours produces transparent YZ03 crystals.
3O Y203F33~ (m, g) cooling to form Yz03 (c) + 3F- (g) In the above equations, p=powder; 1=liquid; g=gas; c=crys-talline; m=molten; and --> = reaction direction and heating.
The proposed Reactions I-IV are assumed to be molecular complex reactions that proceed by shifting chemical equilibria irreversibly to the right to produce refractory oxides.
9 A general implementation of the above UCDP manufacturing thermochemical reactions is as follows:
1. Write the appropriate chemical equations and calculate:
a) reactant weighs;
b) product weight percent loss for each reaction.
2. Use either ultrapure reactants or off-the-shelf chemical reactants which include: a) at least one halide and li-quid water; or b) at least one oxide, at least one halide and liquid water; or, c) at least one hydrolyzable member of the group consisting of a metal oxide and a hydrogen halide composition or a combination thereof. Calculate and weigh out each reactant and, sequentially, homogene-ously dry-mix the reactants, mix with water to form a ho-mogeneously dispersed colloidal state, dry the uniform mixture up to about 150°C, and pulverize and sieve the mixture through a 200 mesh screen (Reaction I).
3. Place the powdered composition in a pre-weighed empty crucible, weigh and program heat the crucible to the ap-propriate temperature and hold for an appropriate time which ensures complete solid state hydroxyhalide complex formation (Reaction II).
4. Cool the furnace; weigh the crucible and determine the composition's wt% loss; pulverize the composition and sieve through 200 mesh screen. Use X-ray analysis to confirm that the precursor complex phase has completely formed.
5. Compact and place the powdered composition in a pre-weighed empty crucible, weigh and program heat the cru-cible to a Reaction III temperature and maintain the con-tents at that temperature for a period of time sufficient to ensure the oxyhalide reaction has gone to completion.
Determine wt o loss, pulverize, sieve and X-ray to con-firm that the presence of the precursor complex phase.
6 Compact the Step 5 composition and program heat it to a Reaction IIIA temperature. Maintain a constant (isother mal) temperature for a sufficient time period to ensure the decomposition of the solid state activated oxyhalide complex.
7. Compact the Step 5 composition and program heat it to a Reaction IV molten temperature.
8. Program cool the molten temperature to a lower molten or solidification temperature; or, isothermally maintain or program cool an end product seed crystal in contact with the molten complex.
9. Heat the compacted composition from Step 5 to within a temperature range from about twenty (20°C) Celsius de-grees to three hundred (300°C) Celsius degrees above the Reaction IV initial molten temperature to obtain a vapor state temperature.
1. Write the appropriate chemical equations and calculate:
a) reactant weighs;
b) product weight percent loss for each reaction.
2. Use either ultrapure reactants or off-the-shelf chemical reactants which include: a) at least one halide and li-quid water; or b) at least one oxide, at least one halide and liquid water; or, c) at least one hydrolyzable member of the group consisting of a metal oxide and a hydrogen halide composition or a combination thereof. Calculate and weigh out each reactant and, sequentially, homogene-ously dry-mix the reactants, mix with water to form a ho-mogeneously dispersed colloidal state, dry the uniform mixture up to about 150°C, and pulverize and sieve the mixture through a 200 mesh screen (Reaction I).
3. Place the powdered composition in a pre-weighed empty crucible, weigh and program heat the crucible to the ap-propriate temperature and hold for an appropriate time which ensures complete solid state hydroxyhalide complex formation (Reaction II).
4. Cool the furnace; weigh the crucible and determine the composition's wt% loss; pulverize the composition and sieve through 200 mesh screen. Use X-ray analysis to confirm that the precursor complex phase has completely formed.
5. Compact and place the powdered composition in a pre-weighed empty crucible, weigh and program heat the cru-cible to a Reaction III temperature and maintain the con-tents at that temperature for a period of time sufficient to ensure the oxyhalide reaction has gone to completion.
Determine wt o loss, pulverize, sieve and X-ray to con-firm that the presence of the precursor complex phase.
6 Compact the Step 5 composition and program heat it to a Reaction IIIA temperature. Maintain a constant (isother mal) temperature for a sufficient time period to ensure the decomposition of the solid state activated oxyhalide complex.
7. Compact the Step 5 composition and program heat it to a Reaction IV molten temperature.
8. Program cool the molten temperature to a lower molten or solidification temperature; or, isothermally maintain or program cool an end product seed crystal in contact with the molten complex.
9. Heat the compacted composition from Step 5 to within a temperature range from about twenty (20°C) Celsius de-grees to three hundred (300°C) Celsius degrees above the Reaction IV initial molten temperature to obtain a vapor state temperature.
10. Obtain a refractory oxide end product compound by: a) maintaining, isothermally, the higher Step 9 temperature for a sufficient time period to ensure that the shifting chemical equilibria caused by the gas-forming reactions and the consuming decomposition reactions of the vapor state activated complexes to solid oxide are completed.
11. Perform X-ray, chemical and infrared absorption analyses on the end product composition.
12. Anneal, if necessary to impart a specific property to the refractory oxide, in an appropriate gaseous environment, such as dry or moist air, OZ, HZ, NZ, CO/COZ, HF, He or Ar.
The temperatures at which the Reactions I-IV occur in the process of this invention range from about ambient (20°C) tem-perature for the initial reaction to about 1700°C for the fi-nal refractory oxide production step and at virtually any pres-sure which does not adversely affect shifting chemical equi-libria reactions. The length of time for a complex to decom-pose is principally a function of the complex composition, the quantity of the complex and the decomposition temperature em-ployed. The reaction time periods are usually maintained for a plurality of hours at designated temperatures to ensure that a complete complex reaction is achieved. These reaction para-meters can be empirically estimated and roughly in situ deter-mined. More sophisticated known in situ thermoanalytical techniques can be used to determine the optimum UCDP reaction kinetic parameters, which can then be precisely reproduced.
The specific decomposition-temperatures used depend upon the specific oxyhalide being thermochemically decomposed but generally is about 100°C to 1500°C below the true melting ".:, point of the corresponding refractory oxide. Ordinarily the temperatures are maintained substantially constant, e.g., within about 5°C and preferably within about 1°C. The generic process of this invention, therefore, provides a precise, highly reproducible yield process for manufacturing all re-fractory oxide compositional categories at lower temperatures than heretofore possible and produces refractory oxide end products which are cationically homogeneous, with nanometer-scale particle sizes, of high quality and purity as verified by chemical and/or X-ray analyses. The invention also pro-vides a method for the manufacture not only of refractory oxide compositions which are presently commercially available but also heretofore commercially unavailable known refractory oxides. The process also enables the manufacture of a poten-tially inexhaustible number of novel refractory compositions, including those disclosed herein.
In the manufacture of refractory oxides by the UCPD, fluorides, chlorides and fluoride-chloride combinations are used. Also additional reactants may be used, such as other halides, hydroxides, carbonates, nitrates and sulfates; wheth-er anhydrous or hydrated. Although ultrapure pure reactants may be used to produce refractory oxides of the highest of purity, off-the-shelf (reagent grade) chemical reactants gen-erally are used because they become highly purified during the complex formation-decomposition reactions. Thus, UCDP refrac tory oxide end products can be manufactured very economically.
In the UCDP's chemical vapor deposition procedure, chlo rides are generally used rather than fluorides because chlo rides melt at much lower temperatures and exhibit much higher vapor pressures at given temperature than fluorides.
Each example below exhibits a decomposition-temperature range derived by heating a small sample reactant mixture to each of the temperatures at which a chemical conversion occurs and maintaining the sample at each of those temperatures for .,,~, ~. ~;.
at least about three hours. Microscopic examinations of the compositions can identify the molten state ranges.
A variety of furnaces and techniques can be used to manu facture refractory oxide compositions by the UCDP from solid, molten, or vapor states. The furnace-pressure capabilities can range from negative pressures (vacuums) to overpressures greater than one atmosphere. Compacted reactant-mixture bil-lets or platinum, ceramic or molybdenum crucibles can be used to hold the reacting compositions in the appropriate gas envi-ronments such as air, nitrogen, oxygen and hydrogen.
Each example below is either a specific representative derivative compound of the parent compound or a specific par-ent compound selected for manufacture from the immediate below general formula group series. Each group is of similar chem-ical-type of compounds, within given concentration range and suggests similar UCDP temperature-range manufacture. No new X-ray lattice constants were determined for doped and solid solution compounds if a JCPD X-ray card does not exist. The lattice constants of these compounds are reported as the stan-dard JCPD values for identical constituent compounds but of different concentrations. In general, a parent compound is one in which the elements' atomic ratios (subscript numbers) are integers.
In the examples, air at atmospheric pressure, was the furnace gas environment used; and, lanthanides are the atomic number elements 57 to 71 of the Chemical Periodic Table.
GENERAL FORMULA GROUP SERIES
The novel refractory oxides described below are produced from a metal oxyhalide precursor, whose structure otherwise corresponds thereto except for the absence of the G9 element, selected from the group consisting of:
1 ) B a ~ _ ~ 2~ S+0.5x )UPRPDsp'xMg1-yDyAl l o- c z+w ) 'TzQo. 75w~ ~ 7 2 ) Ba2_2pNa~ _ ~X-P)RxRpNbS-yTaY0~5
The temperatures at which the Reactions I-IV occur in the process of this invention range from about ambient (20°C) tem-perature for the initial reaction to about 1700°C for the fi-nal refractory oxide production step and at virtually any pres-sure which does not adversely affect shifting chemical equi-libria reactions. The length of time for a complex to decom-pose is principally a function of the complex composition, the quantity of the complex and the decomposition temperature em-ployed. The reaction time periods are usually maintained for a plurality of hours at designated temperatures to ensure that a complete complex reaction is achieved. These reaction para-meters can be empirically estimated and roughly in situ deter-mined. More sophisticated known in situ thermoanalytical techniques can be used to determine the optimum UCDP reaction kinetic parameters, which can then be precisely reproduced.
The specific decomposition-temperatures used depend upon the specific oxyhalide being thermochemically decomposed but generally is about 100°C to 1500°C below the true melting ".:, point of the corresponding refractory oxide. Ordinarily the temperatures are maintained substantially constant, e.g., within about 5°C and preferably within about 1°C. The generic process of this invention, therefore, provides a precise, highly reproducible yield process for manufacturing all re-fractory oxide compositional categories at lower temperatures than heretofore possible and produces refractory oxide end products which are cationically homogeneous, with nanometer-scale particle sizes, of high quality and purity as verified by chemical and/or X-ray analyses. The invention also pro-vides a method for the manufacture not only of refractory oxide compositions which are presently commercially available but also heretofore commercially unavailable known refractory oxides. The process also enables the manufacture of a poten-tially inexhaustible number of novel refractory compositions, including those disclosed herein.
In the manufacture of refractory oxides by the UCPD, fluorides, chlorides and fluoride-chloride combinations are used. Also additional reactants may be used, such as other halides, hydroxides, carbonates, nitrates and sulfates; wheth-er anhydrous or hydrated. Although ultrapure pure reactants may be used to produce refractory oxides of the highest of purity, off-the-shelf (reagent grade) chemical reactants gen-erally are used because they become highly purified during the complex formation-decomposition reactions. Thus, UCDP refrac tory oxide end products can be manufactured very economically.
In the UCDP's chemical vapor deposition procedure, chlo rides are generally used rather than fluorides because chlo rides melt at much lower temperatures and exhibit much higher vapor pressures at given temperature than fluorides.
Each example below exhibits a decomposition-temperature range derived by heating a small sample reactant mixture to each of the temperatures at which a chemical conversion occurs and maintaining the sample at each of those temperatures for .,,~, ~. ~;.
at least about three hours. Microscopic examinations of the compositions can identify the molten state ranges.
A variety of furnaces and techniques can be used to manu facture refractory oxide compositions by the UCDP from solid, molten, or vapor states. The furnace-pressure capabilities can range from negative pressures (vacuums) to overpressures greater than one atmosphere. Compacted reactant-mixture bil-lets or platinum, ceramic or molybdenum crucibles can be used to hold the reacting compositions in the appropriate gas envi-ronments such as air, nitrogen, oxygen and hydrogen.
Each example below is either a specific representative derivative compound of the parent compound or a specific par-ent compound selected for manufacture from the immediate below general formula group series. Each group is of similar chem-ical-type of compounds, within given concentration range and suggests similar UCDP temperature-range manufacture. No new X-ray lattice constants were determined for doped and solid solution compounds if a JCPD X-ray card does not exist. The lattice constants of these compounds are reported as the stan-dard JCPD values for identical constituent compounds but of different concentrations. In general, a parent compound is one in which the elements' atomic ratios (subscript numbers) are integers.
In the examples, air at atmospheric pressure, was the furnace gas environment used; and, lanthanides are the atomic number elements 57 to 71 of the Chemical Periodic Table.
GENERAL FORMULA GROUP SERIES
The novel refractory oxides described below are produced from a metal oxyhalide precursor, whose structure otherwise corresponds thereto except for the absence of the G9 element, selected from the group consisting of:
1 ) B a ~ _ ~ 2~ S+0.5x )UPRPDsp'xMg1-yDyAl l o- c z+w ) 'TzQo. 75w~ ~ 7 2 ) Ba2_2pNa~ _ ~X-P)RxRpNbS-yTaY0~5
13 3 ) Sr1-(x+2P)BaxUPRPJ0.67Nb2-yTay~6 4 ) Ba1_xDXTi1_(y+o.75z)JzZry~3 ) KTa1 _ (x+o.by>NbxJy03 6 ) L1.1-(x+Z+d)D0.5xD0.5dJ0.33zTa1-yNby03 5 7) Mg1_(x+y+z)Dz'T0.67yR0.67x~
8 ) Mg1 _xDxAl2_yJY04 9 ) Pb2_zDZK1-xNaxNbS_yTay015 ) Y2_xRxJd03 11 ) AlZ_(x+y+w)RxJyQ0.75w~3 10 12 ) Y3_xRxAlS(v+w)JyQ0.75w~12 13 ) Y3_xRxFeS_yJY012 where "U", "D", "R", "J" and "Q" are as defined hereinabove.
The UCDP manufacturing procedure, which illustrates Reac-tions I-IV, as already set forth, is responsible for the pro-duction of an assortment of compositions. The below examples are given to exemplify the UCDP and the scope of the invention and are not intended to be limiting in the sense of the scope of the invention.
EXAMPLE I
General Formula Ba1_ ~S+0.5x)RQ. 7PDsUxMg1-yD~1110-(z+w 'TzQ0.75wD17 R=Y, ~lant~ani~es; DS=Ca, Sr, ~b; U=K, Na;
Dy=Co, Cu, Ge, Ni, Zn; J=Cr, Ga, Ti, Mn, V, Fe, Co;
Q=Si, Ge;
Osps0.6; 0.05sss1; Osws7.5;
Osxsl.2; Osysl; Oszs0.6 Specific End Product Compound Ba0.9oNao.05Nd0.05Mgp'19.914CrQ.006T10.08~17 ( C ) (New Composition) The temperature of a three gram reactant mixture, con-sisting of, in mole %, 3.12BaFz,+ 0.02NaF + 0.02NdF3 + 3.5MgFZ
+ 20.6A1F3 + 6.9A1Z03 + O.OlTiz03 + 58.5H20, in an alumina crucible, was raised to the isothermal decomposition-temper-ature of 1370°C for five (5) hours. The temperature was then programmed cooled at 15°C per hour to 1175°C and the furnace cooled to room temperature. The cation reactant concentra-tions were: A1=82.6 at.o, Mg=8.3 at.%, Ba=7.5 at.%, Ti=0.7
8 ) Mg1 _xDxAl2_yJY04 9 ) Pb2_zDZK1-xNaxNbS_yTay015 ) Y2_xRxJd03 11 ) AlZ_(x+y+w)RxJyQ0.75w~3 10 12 ) Y3_xRxAlS(v+w)JyQ0.75w~12 13 ) Y3_xRxFeS_yJY012 where "U", "D", "R", "J" and "Q" are as defined hereinabove.
The UCDP manufacturing procedure, which illustrates Reac-tions I-IV, as already set forth, is responsible for the pro-duction of an assortment of compositions. The below examples are given to exemplify the UCDP and the scope of the invention and are not intended to be limiting in the sense of the scope of the invention.
EXAMPLE I
General Formula Ba1_ ~S+0.5x)RQ. 7PDsUxMg1-yD~1110-(z+w 'TzQ0.75wD17 R=Y, ~lant~ani~es; DS=Ca, Sr, ~b; U=K, Na;
Dy=Co, Cu, Ge, Ni, Zn; J=Cr, Ga, Ti, Mn, V, Fe, Co;
Q=Si, Ge;
Osps0.6; 0.05sss1; Osws7.5;
Osxsl.2; Osysl; Oszs0.6 Specific End Product Compound Ba0.9oNao.05Nd0.05Mgp'19.914CrQ.006T10.08~17 ( C ) (New Composition) The temperature of a three gram reactant mixture, con-sisting of, in mole %, 3.12BaFz,+ 0.02NaF + 0.02NdF3 + 3.5MgFZ
+ 20.6A1F3 + 6.9A1Z03 + O.OlTiz03 + 58.5H20, in an alumina crucible, was raised to the isothermal decomposition-temper-ature of 1370°C for five (5) hours. The temperature was then programmed cooled at 15°C per hour to 1175°C and the furnace cooled to room temperature. The cation reactant concentra-tions were: A1=82.6 at.o, Mg=8.3 at.%, Ba=7.5 at.%, Ti=0.7
14 at%, Na=0.4 at.%, Nd=0.4 at.%, Cr=0.1 at.%. The X-ray purity is 99%. The crystal class is hexagonal where a=5.625A and c=22.62A. After materials characterization, the compound is then ready for potential fabrications and applications, such as a solid state electrolyte, phosphor, red or tunable laser.
EXAMPLE II
General Formula Ll~-~x+z+d Do.SxDo.Sd'T0.33zTa1-yNby03 Dx = Ni, Co, ~e, Mg; Dd= Ni, Co, Cu, Zn;
J = Cr, Fe; G = F, Cl;
Osds0.12; Osxsl; Osysl; Oszs0.4 Specific End Product Compound LlTap,65Nb0.35~3 ( C ) The temperature of a three gram reactant mixture, con-sisting of , in mole % , 50LiF + 8 . 8Nbz05 + 16 . 3TaZ05 + 25H20, in an alumina crucible, was raised to the isothermal decomposi-tion-temperature of 1160°C for five (5) hours. The tempe-rature was then programmed cooled at 20°C per hour to 1000°C
and the furnace cooled to room temperature. The crystal structure is rhombohedral with a=5.1539A and c=13.81512A.
After materials characterization, the compound is then ready for potential electro-mechanical transduction fabrications and applications.
EXAMPLE III
General Formula Mg1-(x+y+z Dz'To.67yRo.67x~
D = Ni, Co, ~e, Cu, Ge, Zn;
J = Cr, Fe, Ti; R = Lanthanides Osxs0.005; Osysl; Oszsl Specific End Product Compound Mg0 ( c ) The temperature of a three gram reactant mixture, con-sisting of in mole %, 50MgFZ + 50Hz0, in a magnesium oxide crucible, was raised to the isothermal decomposition-tempera-ture of 1290°C for eight (8) hours. The temperature was then programmed cooled at 20°C per hour to 1050°C and the furnace cooled to room temperature. The cation reactant concentrat-ions was : Mg=100 at . % . The X-ray purity is 100 % . The crystal class is cubic with a=4.213A. The product is suitable for use in infrared transmission and substrate fabrications and appli-cations.
_ _~
~-~ 2131326 EXAMPLE IV
General Formula Pb2_ ZDZK1 _XNaXNbS_YTaY015 DZ = Ba, Ca;
Osxsl; Osys5; Oszs2 Specific End Product Compound Pb2KNb5015 ( C ) The temperature of a three gram reactant mixture, con-sisting of , in mole o , 25PbF2, + 12 . 5KF + 31 . 3Nb205 + 31 . 3H20, in an alumina crucible, was raised to the isothermal decomposi-tion-temperature of 1120°C for five (5) hours. The tempera-ture was then programmed cooled at 10 ° C per hour to 10 70 ° C
and the furnace cooled to room temperature. The cation reactant concentrations were:
Pb=25.0 at.%, K=12.5 at.%, Nb=62.5 at. o.
The crystal class is orthorhombic with a=17.757A, b=18.O11A, c=3.917A. The product can be used in ferroelectric-ferro-elastic fabrications and applications.
EXAMPLE V
General Formula Y3_XRXA15_ (.Y+w)'TYQ0.75w~12 J = Cr, Ga, Ti, Fe, V, Co, Mn;
Q = Si, Ge; R = Lanthanides Osxs3; Osys0.5; Osws5;
Specific End Product Compound Y2.71Nd0.2~14.994Cr0.006~12 ( C ) The temperature of a three gram reactant mixture, con-sisting of in mole% of , 13 . 6YF3, + 1 . 5NdF3 + 14 . 9A1F~ + 5A1203 +
60H20 + 150ppm Cr203, in an alumna crucible, was raised to the isothermal decomposition-temperature of 1430°C for six (6) hours . The temperature was then programmed cooled at 15 ° C per hour to 1150°C and the furnace cooled to room temperature.
The cation reactant concentrations were:
Y=33.87 at.o, Nd=3.63 at.%, A1=62.42 at.%, Cr=0.08 at.%.
The X-rah purity is 99%. The crystal class is cubic where a=12.009A. The product is suitable for use in doubly doped laser fabrications.
While the embodiments described herein are illustrative of the principles of this UCDP invention, various modifica-_~
r.
.e tions and advantages may be achieved by those skilled in the art without departing from the scope and the spirit of this invention; as defined by the following claims.
EXAMPLE II
General Formula Ll~-~x+z+d Do.SxDo.Sd'T0.33zTa1-yNby03 Dx = Ni, Co, ~e, Mg; Dd= Ni, Co, Cu, Zn;
J = Cr, Fe; G = F, Cl;
Osds0.12; Osxsl; Osysl; Oszs0.4 Specific End Product Compound LlTap,65Nb0.35~3 ( C ) The temperature of a three gram reactant mixture, con-sisting of , in mole % , 50LiF + 8 . 8Nbz05 + 16 . 3TaZ05 + 25H20, in an alumina crucible, was raised to the isothermal decomposi-tion-temperature of 1160°C for five (5) hours. The tempe-rature was then programmed cooled at 20°C per hour to 1000°C
and the furnace cooled to room temperature. The crystal structure is rhombohedral with a=5.1539A and c=13.81512A.
After materials characterization, the compound is then ready for potential electro-mechanical transduction fabrications and applications.
EXAMPLE III
General Formula Mg1-(x+y+z Dz'To.67yRo.67x~
D = Ni, Co, ~e, Cu, Ge, Zn;
J = Cr, Fe, Ti; R = Lanthanides Osxs0.005; Osysl; Oszsl Specific End Product Compound Mg0 ( c ) The temperature of a three gram reactant mixture, con-sisting of in mole %, 50MgFZ + 50Hz0, in a magnesium oxide crucible, was raised to the isothermal decomposition-tempera-ture of 1290°C for eight (8) hours. The temperature was then programmed cooled at 20°C per hour to 1050°C and the furnace cooled to room temperature. The cation reactant concentrat-ions was : Mg=100 at . % . The X-ray purity is 100 % . The crystal class is cubic with a=4.213A. The product is suitable for use in infrared transmission and substrate fabrications and appli-cations.
_ _~
~-~ 2131326 EXAMPLE IV
General Formula Pb2_ ZDZK1 _XNaXNbS_YTaY015 DZ = Ba, Ca;
Osxsl; Osys5; Oszs2 Specific End Product Compound Pb2KNb5015 ( C ) The temperature of a three gram reactant mixture, con-sisting of , in mole o , 25PbF2, + 12 . 5KF + 31 . 3Nb205 + 31 . 3H20, in an alumina crucible, was raised to the isothermal decomposi-tion-temperature of 1120°C for five (5) hours. The tempera-ture was then programmed cooled at 10 ° C per hour to 10 70 ° C
and the furnace cooled to room temperature. The cation reactant concentrations were:
Pb=25.0 at.%, K=12.5 at.%, Nb=62.5 at. o.
The crystal class is orthorhombic with a=17.757A, b=18.O11A, c=3.917A. The product can be used in ferroelectric-ferro-elastic fabrications and applications.
EXAMPLE V
General Formula Y3_XRXA15_ (.Y+w)'TYQ0.75w~12 J = Cr, Ga, Ti, Fe, V, Co, Mn;
Q = Si, Ge; R = Lanthanides Osxs3; Osys0.5; Osws5;
Specific End Product Compound Y2.71Nd0.2~14.994Cr0.006~12 ( C ) The temperature of a three gram reactant mixture, con-sisting of in mole% of , 13 . 6YF3, + 1 . 5NdF3 + 14 . 9A1F~ + 5A1203 +
60H20 + 150ppm Cr203, in an alumna crucible, was raised to the isothermal decomposition-temperature of 1430°C for six (6) hours . The temperature was then programmed cooled at 15 ° C per hour to 1150°C and the furnace cooled to room temperature.
The cation reactant concentrations were:
Y=33.87 at.o, Nd=3.63 at.%, A1=62.42 at.%, Cr=0.08 at.%.
The X-rah purity is 99%. The crystal class is cubic where a=12.009A. The product is suitable for use in doubly doped laser fabrications.
While the embodiments described herein are illustrative of the principles of this UCDP invention, various modifica-_~
r.
.e tions and advantages may be achieved by those skilled in the art without departing from the scope and the spirit of this invention; as defined by the following claims.
Claims (3)
1. A process for producing a refractory oxide which comprises:
(a) reacting and dispersal-blending liquid water with at least one metal halide reactant to produce a fully-hydrated, cationically-homogeneous nanostructured colloidal mixture;
(b) heating the colloidal mixture to produce a solid state metal hydroxyhalide;
(c) further heating the metal hydroxyhalide to a higher temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state metal oxyhalide; and (d) performing one of the following heating steps:
(i) heating the metal oxyhalide to a solid state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide;
(ii) heating the metal oxyhalide to a molten state decomposition-tempera-ture at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide; or (iii) heating the metal oxyhalide to a vapor state decomposition-tempera-ture at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide.
(a) reacting and dispersal-blending liquid water with at least one metal halide reactant to produce a fully-hydrated, cationically-homogeneous nanostructured colloidal mixture;
(b) heating the colloidal mixture to produce a solid state metal hydroxyhalide;
(c) further heating the metal hydroxyhalide to a higher temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state metal oxyhalide; and (d) performing one of the following heating steps:
(i) heating the metal oxyhalide to a solid state decomposition-temperature at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide;
(ii) heating the metal oxyhalide to a molten state decomposition-tempera-ture at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide; or (iii) heating the metal oxyhalide to a vapor state decomposition-tempera-ture at which it chemically decomposes, by heat alone, into a cationically-homogeneous nanostructured solid state refractory oxide.
2. A process according to claim 1, wherein step (a) comprises reacting and dispersal-blending liquid water with at least one metal halide reactant and at least one metal oxide reactant to produce a fully-hydrated, cationically-homogeneous nano-structured colloidal mixture.
3. A process according to claim 2, wherein the reactants are Y=33.87 at.%, Nd=3.63 at.%, Al=62.42 at.%, Cr=0.08 at.% and the refractory oxide is Y2.71Nd0.29Al4.994Cr0.006O12.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA002455428A CA2455428C (en) | 1992-02-28 | 1993-03-01 | Production of cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US84321892A | 1992-02-28 | 1992-02-28 | |
| US07/843,218 | 1992-02-28 | ||
| PCT/US1993/001846 WO1993017959A1 (en) | 1992-02-28 | 1993-03-01 | Production of transparent cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures |
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| CA002455428A Division CA2455428C (en) | 1992-02-28 | 1993-03-01 | Production of cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures |
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| CA002131326A Expired - Lifetime CA2131326C (en) | 1992-02-28 | 1993-03-01 | Production of cationically homogeneous refractory oxides of nanometer-scale particle size diameters at reduced temperatures |
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| IT1277836B1 (en) * | 1995-03-13 | 1997-11-12 | Colorobbia Italiana Spa | ALUMINATES OF Yttrium AND / OR RARE EARTH WITH PEROVSKITIC STRUCTURE, THEIR PREPARATION AND USE AS PIGMENTS |
| DK172530B1 (en) | 1995-11-10 | 1998-11-23 | Leo Pharm Prod Ltd | Additive product for drinking water and animal feed and method of addition |
| KR100290437B1 (en) * | 1998-10-07 | 2001-09-22 | 박찬구 | Preparation of Niodymium Halogen Complexes Suitable for Continuous 1,3-Butadiene Polymerization |
| US6316377B1 (en) | 1999-09-10 | 2001-11-13 | Battelle Memorial Institute | Rare earth oxide fluoride nanoparticles and hydrothermal method for forming nanoparticles |
| CN105905930B (en) * | 2016-04-12 | 2017-10-20 | 广西华银铝业有限公司 | Sodium aluminate solution refines filter aid and prepared and filter cake Application way in alumina producing |
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| US2942944A (en) * | 1958-11-26 | 1960-06-28 | Harley A Wilhelm | Process of preparing zirconium oxychloride |
| US3148943A (en) * | 1962-12-26 | 1964-09-15 | M & T Chemicals Inc | Novel process for preparing antimony oxychloride |
| US3370017A (en) * | 1963-07-30 | 1968-02-20 | Du Pont | Microcrystalline corundum powder, sols thereof, and processes for preparing both |
| US3607770A (en) * | 1968-10-23 | 1971-09-21 | Gen Electric | Gaseous reaction process for the production of rare earth oxyhalide and oxide luminescent materials |
| US4271131A (en) * | 1979-04-11 | 1981-06-02 | Foote Mineral Company | Production of highly pure lithium chloride from impure brines |
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1993
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| CA2455428A1 (en) | 1993-09-16 |
| CA2455428C (en) | 2004-10-05 |
| WO1993017959A1 (en) | 1993-09-16 |
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