Abstract: A hydrometallurgical process for producing zinc oxide from an aqueous solution containing zinc ions is provided. The process comprises the steps of contacting a zinc solution with an insoluble organic solvent selective to the extraction of zinc and thereby produce a zinc-loaded organic solvent. The zinc is then stripped from the zinc-loaded organic solvent with a solution of nitric acid to form a solution of zinc nitrate. The zinc nitrate solution is subjected to thermal hydrolysis at an elevated temperature in the presence of pressurized water vapor, the temperature being at least sufficient to decompose the zinc nitrate to zinc oxide which is thereafter recovered.

Abstract: Disclosed are compositions for application to a surface to protect the surface from ultra-violet radiation, which include zinc oxide particles having a substantially rod shape.

Abstract: The composite oxide comprises, by weight, 100 parts of zinc oxide and at least one member, incorporated therein, selected from seven specific oxides in their specific amounts such as 0.001 to 5.0 parts of lanthanum oxide, 1.0 to 10.0 parts of cobalt oxide, 1.0 to 30.0 parts of titanium oxide, the composite oxide being surface treated with a silicone oil or a fatty acid to provide a surface-treated composite oxide of the present invention which has excellent ultraviolet screening capability and high visible light transmittance, these superior properties being well balanced with each other, and can maintain said superior properties over a long period of time. In one embodiment, there is provided a process for producing the ultraviolet screening surface-treated composite oxide.

Abstract: A composite metal hydroxide is provided for use as a flame-retardant in a resin or rubber composition. The composite metal hydroxide is a solid solution having the formula (1) Ca.sub.1-x M.sup.2+ x(OH).sub.2. M is at least one member selected from the group consisting of Mg, Mn, Fe, Co, Ni, Cu and Zn and x is in the range of 0.001.ltoreq.x<0.995. Two preferred composite metal hydroxides have the formula (2) Ca.sub.1-x Mg.sup.2+ x(OH).sub.2 wherein x is in the range of 0.001.ltoreq.x<0.995 and the formula (3) Ca.sub.1-x (Mg, Ni, Mn).sub.x (OH).sub.2 wherein x is in the range of 0.001.ltoreq.x<0.

Abstract: A piezoelectric semiconductor is a single crystal composed mainly of ZnO having properties such as electrical conductivity of 10.sup.-11 .about.10.sup.-3 1/.OMEGA..multidot.cm suitable for use as an acoustoelectric element, by adding a given amount of H.sub.2 O.sub.2 to the alkali solvent, or by using NH.sub.4 OH in the alkali solvent, or by doping the ZnO single crystal with Li or a trivalent metal. The piezoelectric semiconductor can be suitably used as a ultrasonic transducer material of acoustoelectric type and can also be used as a material for ultrasonic amplification, an surface acoustic wave filter, a piezoelectric transducer, a fluorescent material for emitting a low-velocity electron beam, etc.

Abstract: A vapor of diethylzinc or dimethylzinc is reacted with water vapor to form very small particles of depleted zinc oxide which are entrained in the gas flow. In accordance with one version of the method, a spray nozzle is used to mix liquid diethylzinc with dry nitrogen to prevent combustion. The nozzle sprays the diluted diethylzinc into a chamber heated up to its boiling point of 118.degree. C. to completely vaporize the diethylzinc. The diluted diethylzinc gas is then reacted with water vapor to form a fume of very small zinc oxide particles entrained in ethane gas without combustion. A similar process can be used to convert dimethylzinc into depleted zinc oxide powder. In accordance with another version of the process, an inert gas stream is saturated with diethylzinc or dimethylzinc vapor by passing a dry inert gas through a vessel containing liquid diethylzinc or dimethylzinc. A second inert gas stream is saturated with water vapor in a similar manner.

Abstract: There is disclosed a pleasant tasting oral rinse composition and a method of using the same. The composition consists essentially of cayenne pepper, calendula, echinacea, goldenseal, propolis, vinegar, and water in certain proportions.

Abstract: Zinc borate compositions having a ZnO:B.sub.2 O.sub.3 ratio of 4:1. The hydrated zinc borate 4ZnO.B.sub.2 O.sub.3.H.sub.2 O and anhydrous zinc borate 4ZnO.B.sub.2 O.sub.3 are especially useful as fire-retardants and smoke-suppressant additives for polymeric compositions.

Abstract: A method is provided for the high yield production of white, electrically conductive zinc oxide which comprises the simultaneous addition to a reactor of (1) an aqueous solution containing a water-soluble zinc compound and at least one water-soluble compound of a metal selected from the group consisting of tin, aluminum, gallium and indium, and (2) an aqueous alkaline solution, while maintaining the resulting neutralization reaction solution at a pH from 6 to 12.5 to obtain coprecipitates, and then calcining the coprecipitates in a reducing atmosphere to obtain said conductive zinc oxide.

Abstract: A lanthanum chromite ceramic powder consisting essentially of 1 mol of LaCr.sub.1-x M.sub.x O.sub.3, where M is a divalent metal selected from the group of zinc, copper and mixtures thereof and x ranges from about 0.02 to 0.2, y mols of B.sub.2 O.sub.3, where y ranges from 0.0005 to 0.04, and z mols of La.sub.2 O.sub.3, where the ratio z/y ranges from 1 to 3, the powder is sintered to high density by firing a compact thereof at a temperature of about 1400.degree. C. in air or other atmosphere, and is particularly suited for use as interconnect material for solid oxide fuel cells.

Abstract: A sinter-reactive lanthanum chromite powder is prepared from the lanthanum chromite precursor LaCr.sub.1-x M.sub.x O.sub.3 (Adsorbate). The powder is crystalline, has the formula LaCr.sub.1-x M.sub.x O.sub.3, where M is selected from the group consisting of zinc, copper and mixtures thereof and x ranges from about 0.02 to 0.2, and sinters to densities higher than about 95% of theoretical density at temperature as low as 1400.degree. C. in oxidizing atmospheres. Sintering to such high density at temperatures in the vicinity of 1400.degree. C. makes the powder particularly suited for use as interconnect material for solid oxide fuel cells.

Abstract: A novel zinc oxide crystal has an octahedral nucleus whose faces are alternately zinc faces and oxide faces, and this crystal has such a geometric shape that a needle is grown on each of the faces. The needle grown on the oxide face is branched into three sections which are disposed in parallel relation, and the needle on the oxide face is shorter than the needle on the zinc face. This novel crystal having oxide films can be produced in a homogeneous manner by mixing zinc-tin alloy powder or tin powder with zinc powder, having an oxide film formed on each particle thereof, to form a powder mixture and then by heating the powder mixture at 820.degree. C. to 1100.degree. C. in an oxidizing atmosphere to oxide the same. The tin concentration in the power mixture is less than 40 wt. %.

Abstract: A new composition and method of making same for a doped zinc oxide microsphere and articles made therefrom for use in an electrical surge arrestor which has increased solid content, uniform grain size and is in the form of a gel.

Abstract: A voltage non-linear resistor element mainly comprising ZnO, substantially free from internal defects, exhibiting an excellent current impulse withstand capability, can be manufactured by a process wherein an SiC inclusion in the starting ZnO powder is restricted to at most 10 ppm, preferably at most 0.1 ppm, by weight, whereby formation of closed pores in the element is prevented, which is otherwise caused by decomposition of considerable amount of SiC during firing. The starting ZnO powder has an average particle diameter (R) of 0.1-2.0 .mu.m, preferably 0.3-0.8 .mu.m, a particle size distribution within the range of between 0.5R and 2R, of at least 70%, preferably 80%, by weight, needle-like crystals of at most 20%, preferably at most 10%, by weight, and an SiC content as an impurity of at most 10 ppm, preferably at most 0.1 ppm, by weight.

Abstract: The present invention provides an improved method of extracting zinc from geothermal brines and synthetic brines which can be performed in a continuous, in-line process and which provides for the advantageous recycling of NH.sub.3 in the process.

Abstract: The present invention provides a novel method of extracting zinc from geothermal brines and synthetic brines which can be performed in a continuous, in-line process.

Abstract: A method for the recovery of zinc oxide from industrial waste materials of various components, including zinc, lead, iron and cadmium, comprising the steps of treating the waste material with an ammonium chloride solution maintained at an elevated temperature, separating the undissolved components from the solution, treating the solution with zinc metal to displace undesired metal ions from the solution, cooling the solution to precipitate therefrom zinc compounds, washing the precipitated zinc compounds to remove unwanted compounds such as diamino zinc dichloride, and drying the remaining zinc compound which is essentially hydrated zinc oxide, resulting in essentially pure zinc oxide.

Abstract: A process is provided for obtaining high quality high surface area zinc oxide from a roasted zinc sulphide concentrate by leaching with an ammoniacal ammonium carbonate solution. The process utilizes optional preliminary oxidation and water leaching steps to remove soluble impurities and an optional aqueous sulphur dioxide leaching step to selectively remove readily soluble zinc oxide. The process includes an improved source of roasted zinc sulphide concentrate. The process also includes an optional reduced pressure calcining step to produce zinc oxide with further increased surface area.

Abstract: A method for producing a lead niobate-based complex oxide with an elevated proportion of pervoskite phase and lead niobate-based complex oxide produced by such method enables manufacture of small actuator or capacitor with an elevated dielectric constant k. Treatment of a raw material represented by a general formula Pb(A.sub.1/3 Nb.sub.#)x(ZN.sub.1/3 Nb.sub.2/3) yO.sub.3 or Pb(Fe.sub.1/2 Nb.sub.1/2)x(Zn.sub.1/3 Nb.sub.2/3) yO.sub.3 (wherein A is Mg or Ni; x is an atomic ratio in a range of 0-1; and y is an atomic ratio in a range of 1-0, with a relation x+y=1) and containing pyrochlore phase, under a high temperature of 500.degree.-1300.degree. C. and a high pressure of 1000-4000 kg/cm.sup.2, causes transition of pyrochlore phase into perovskite phase, thereby increasing the proportion of perovskite phase. Also treatment of a raw material represented by a general formula uPb(.sub.1/3 Nb.sub.2/3)O.sub.3 -vPbTiO.sub.3 (wherein u is an atomic ratio in a range of 0.5-1; and v is an atomic ratio in a range of 0.

Abstract: A conductive composition containing at least zinc oxide whiskers. The conductive composition can be used to provide a conductive resing composition and a conductive coating composition, which have various uses, particularly in conductive layers, conductive supports or protective layers of electrophotographic photosensitive members.

Abstract: A zinc- and lead-containing residue from a metallurgical plant is reprocessed by a thermal treatment in a circulating fluidized bed system. A major part of the heat demand is satisfied by a combustion of solid carbonaceous material in the fluidized bed reactor of the circulating fluidized bed system. A reducing fluidizing gas, which is virtually free of free oxygen, is fed to the lower part of the fluidized bed reactor. A solid carbon content of from 5 to 30% is adjusted in the fluidized bed in the lower portion of the fluidized bed reactor, which is supplied in its upper portion with oxygen-containing gases and in which CO.sub.2 is formed only at such a rate that zinc metal is not reoxidized. Substantially all solids are removed in a recycling cyclone from the suspension discharged from the reactor and the removed solids are recycled. The gas is cooled to a temperature at which zinc metal is oxidized to ZnO. The dust-like zinc compounds and lead compounds are removed from the gas.

Abstract: Process for the manufacture of a powder of mixed metal oxides by cohydrolysis of metal alcoholates in the presence of an acidic organic compound and mixed metal oxide powders in which the molar relationships R1 and R2 of a metal oxide to the sum of the metal oxides in the powder and in a particle of the powder are such that ##EQU1## The process applies especially well to powders of zirconia doped with yttrium oxide or other oxides.

Abstract: A method for manufacturing a precursor powder for use in making a varistor is disclosed. This precursor powder is produced by preparing a homogeneous aqueous dispersion of metal oxides and/or metal hydroxides and heating the dispersion in a closed pressure reactor to a temperature between 200.degree. C. and 350.degree. C. for hydrothermally treating the homogeneous dispersion. The precursor powder produced in the afore-described method is highly homogeneous and of controlled crystal phase and morphology and after mixing with zinc oxide powder can homogeneously be reacted with the zinc oxide in a ceramic process.

Abstract: A zinc oxide-hydroxide complex produced by heating freshly prepared zinc hydroxide at a temperature from about 150.degree. C. to about 450.degree. C. is useful as an adsorbent for malodorous gases such as hydrogen sulfide, mercaptans and the like. The complex alone or its combination with aluminum dihydrogen tripolyphosphate may be incorporated into a synthetic thermoplastic resin for fabricating shaped plastic articles for deodorant uses.

Abstract: A needle-like monoammine complex of zinc carbonate containing or not containing aluminum useful as a filler or a precursor of needle-like electroconductive zinc oxide, and a process for producing it which comprises steps of dissolving a zinc compound in a solution containing ammonium ion and carbonate ion in the presence or absence of aluminum compound and then lowering pH of the solution to precipitate zinc carbonate.

Abstract: A white colored deodorizer comprising zinc oxide and at least one oxide selected from the group consisting of aluminium oxide and silicon oxide and a method for preparation of it are disclosed.

Abstract: A white colored deodorizer comprising titanium oxide and zinc oxide and a method for its preparation are disclosed.

Abstract: Needle-like electrically conductive zinc oxide filler having low specific volume resistance and excellent electrical conductivity-imparting effect per unit weight thereof is provided, including a method for its preparation.

Abstract: There is disclosed a doped zinc oxide pigment composition and method of preparing said composition, wherein the dopant is uniformly dispersed in the zinc oxide matrix in the form of a solid solution such that the mechanism by which undoped zinc oxide absorbs blue or near ultraviolet light is suppressed, thereby yielding a whiter composition. Preferred dopants are Al and Li.

Abstract: Flaky fine particles of zinc oxide have an average particle diameter of 0.1 to 1 micron, an average particle thickness of 0.01 to 0.2 micron and a mean platy ratio (aspect ratio) of at least 3. They are useful as an ingredient for an external composition containing a medicine or cosmetic.

Abstract: A photoconductive cell comprises a photodetector section which consists of an aggregate of tetrapod-like zinc oxide whiskers. Each whisker consists of a core and needle-shaped crystals extending in four different directions from the core. Since this novel tetrapod-like zinc oxide whisker consists of single crystal zinc oxide, it suffers less deterioration. In addition, since the single crystals are transparent and an aggregate thereof has a high porosity, light tends to enter deep portions of the cell so that it exhibits high sensitivity.

Abstract: Metal oxides prepared by exchange reactions between organosemiconductor oxides (such as disiloxanes) and metal coordination compounds (such as neutral metal complexes, metal chelates and chlorometalates), metallic halides (such as zinc chloride), or organometallic compounds (such as methylithium) in inert environments and anhydrous solvents.

Abstract: Layered divalent metal pentavalent metallate, M(HAO.sub.4).sub.x (RAO.sub.3).sub.y (Z).sub.z wherein M is divalent metal, A is a pentavalent metal, e.g. phosphorus, R is a substituent group other than H or OH, e.g., phenyl, covalently bonded to A, x+y=1, y is greater than 0, z ranges from 0 to 2, inclusive, and Z is an intercalated moiety is prepared by contacting a source of divalent metal with a substituted phosphonic acid-type compound under hydrothermal conditions.

Abstract: Whiskers of zinc oxide whose crystal structure includes a central body and four needle crystal projections radially extending from said central body are described. The whiskers are so unique a structure that they are applicable to various materials such as metals, resins, ceramics and the like as a reinforcing material. The whiskers may be in the form of a mixture of whiskers of zinc oxide having crystal structures including two, three, four and/or five needle crystal projections. A method for preparing such whiskers is also described.

Abstract: Ceramic precursor mixtures containing a metal cation, a carbohydrate, and an anion capable of participating in an anionic oxidation-reduction reaction with the carbohydrate for continuous or batchwise drying and pyrolyzing to provide ceramic powders.

Abstract: A process is provided for obtaining high quality high surface area zinc oxide from a roasted zinc sulphide concentrate by leaching with an ammoniacal ammonium carbonate solution. The process utilizes optional preliminary oxidation and water leaching steps to remove soluble impurities and an optional aqueous sulphur dioxide leaching step to selectively remove readily soluble zinc oxide. The process also includes an optional reduced pressure calcining step to produce zinc oxide with further increased surface area.

Abstract: This invention relates to the metallurgy of iron and particularly to the separation and recovery of metals from electric arc furnace (EAF) dusts. While the invention discloses a process for the separation and recovery applicable to zinc, lead, cadmium and antimony contained in such EAF dusts, the invention is particularly applicable to the separation and recovery of zinc. This invention describes a method for reducing the zinc contained in an EAF dust, volatilizing the metallic zinc so produced from the mass of the dust, and reoxidizing the metallic zinc to zinc oxide along with the simultaneous regeneration of hydrogen which can be recycled to treat additional EAF dust.

Abstract: Layered divalent metal pentavalent metallate, M(HAO.sub.4).sub.x (RAO.sub.3).sub.y (Z).sub.z wherein M is divalent metal, A is a pentavalent metal, e.g. phosphorus, R is a substituent group other than H or OH, e.g., phenyl, covalently bonded to A, x+y=1, y is greater than O, z ranges from 0 to 2, inclusive, and Z is an intercalated moiety is prepared by contacting a source of divalent metal with a substituted phosphonic acid-type compound under hydrothermal conditions.

Abstract: Crystalline molecular sieves having three-dimensional microporous framework structures of MO.sub.2.sup.n, AlO.sub.2, and PO.sub.2 tetrahedral oxide units are disclosed. These molecular sieves have an empirical chemical composition on an anhydrous basis expressed by the formula:mR:(M.sub.x Al.sub.y P.sub.z)O.sub.2wherein "R" represents at least one organic templating agent present in the intracrystalline pore system; "M" represents iron and/or titanium, and at least one of cobalt, magnesium, manganese and zinc; "n" is 0, -1 or -2; "m" represents the molar amount of "R" present per mole of (M.sub.x Al.sub.y P.sub.z)O.sub.2 ; and "x", "y" and "z" represent the mole fractions of "M", aluminum and phosphorus, respectively, present as tetrahedral oxides. Their use as adsorbents, catalysts, etc. is also disclosed.

Abstract: A process for adjusting at least one of the structural and surface characteristics of an oxide material, e.g. SiO.sub.2 or Al.sub.2 O.sub.3, by dehydration of a water-containing oxide gel under supercritical conditions by extracting the water with an extraction agent such as CO.sub.2 at a pressure above the critical pressure of the extraction agent.

Abstract: Iron-containing zinc sulfide concentrate is processed to recover zinc values therefrom. The concentrate is roasted to convert zinc sulfide and iron sulfide to their oxides while adequate sulfide-sulfur is retained to maintain the iron values in the ferrous state and thereby avoid ferrite formation. Zinc oxide and iron oxide values are recovered from the roast, simultaneously or sequentially, and residual zinc sulfide may be recycled to the roasting step.

Abstract: Here is provided an adsorbent for adsorbing and removing an arsenic compound which becomes a catalyst poison in a selective contact reduction process for removing nitrogen oxides (NOx) from a combustion exhaust gas by the use of an ammonia as a reducing agent and a denitrating catalyst.The adsorbent of the present invention comprises a material in which the total volume of pores is 0.2 to 0.7 cc/g and the volume of the pores having a pore diameter of 300 .ANG. or more is 10% or more with respect to the total pore volume, and the material is a specific element, its oxide, an ion-exchanged zeolite or the like.In addition, the present invention is directed to a method for removing the arsenic compound from the combustion exhaust gas by injecting the adsorbent into the flow of the gas on the upstream side of the denitrating catalyst.

Abstract: An improved process for the manufacture of a metal oxide is disclosed. In the process wherein a hydrolyzable organometallic compound is hydrolyzed by an alkaline hydrolyzing agent in an alkaline organic solvent, and thereafter, the metal oxide is formed by a condensation reaction of a metal hydroxide resulting from the hydrolysis of the organometallic compound, the improvement comprises feeding the organometallic compound and the hydrolyzing agent into the organic solvent so that a concentration of the hydrolyzed compound is initially above a critical level of supersaturation, and thereafter, is maintained in a range from above an upper limit of solubility to the critical level of super-saturation. According to the above process, the metal oxide can be obtained in the form of a powder material with a uniform particle size distribution.

Abstract: Process for the manufacture of vitreous metal oxides in which a metal alcoholate derived from an alcohol, the pka of which is less than 15.74, is hydrolysed with an aqueous medium, the pH of which is greater than 1.5. The process is applied especially to the manufacture of vitreous zirconium oxide.

Abstract: Prepare highly pure zinc oxide spherodial particles of narrow size distribution and having a mean particle diameter of from about 0.1 to about 0.3 .mu.m by hydrolyzing hydrocarbyl zinc hydrocarboxides, such as ethyl zinc t-butoxide.

Abstract: A finely divided metal oxide powdery composition, preferably with a narrow particle size distribution, is produced from a particulate, sol-gel derived composition containing agglomerates by heating the particulate composition in the presence of an effective amount of a composition which decomposes upon heating and forms a gas to break at least a portion of the agglomerates so as to yield the desired finely divided ceramic particle composition. Examples of suitable gas-forming agents for use in the present invention include the ammonium salts or amides of organic and inorganic acids, volatile acids, and gases dissolved in a suitable solvent, such as water, alcohol or ammonia.

Abstract: Ultrafine particles of ceramic or metallic material are obtained at low temperatures from a nitrate source capable of endothermic decomposition by molecularly combining under a nitrogen atmosphere the nitrate source with an inorganic reducing fuel compound, such as hydrazine, to provide a chemical precursor for the ceramic or metallic material and then exothermically decomposing the precursor in a controlled atmosphere by heating to a temperature up to about 200.degree. C. below the endothermic decomposition temperature of the nitrate source. The nitrate source is a metal nitrate or a mixture of nitrate salts. Ferrite particles are recovered when the nitrate source is a mixture of nitrate salts containing ferric nitrate in a 2:1 molar ratio with at least one additional metal nitrate.

Abstract: Durable, porous sulfur sorbents useful in removing hydrogen sulfide from hot coal gas are prepared by water pelletizing a mixture of fine zinc oxide and fine iron oxide with inorganic and organic binders and small amounts of activators such as sodium carbonate and molybdenite; the pellets are dried and then indurated at a high temperature, e.g., 1800.degree. C., for a time sufficient to produce crush-resistant pellets.

Abstract: Efficient, regenerable sorbents for removal of H.sub.2 S from high temperature gas streams comprise porous, high surface area particles. A first class of sorbents comprise a thin film of binary oxides that form a eutectic at the temperature of the gas stream coated onto a porous, high surface area refractory support. The binary oxides are a mixture of a Group VB or VIB metal oxide with a Group IB, IIB or VIII metal oxide such as a film of V-Zn-O, V-Cu-O, Cu-Mo-O, Zn-Mo-O or Fe-Mo-O coated on an alumina support. A second class of sorbents consist of particles of unsupported mixed oxides in the form of highly dispersed solid solutions of solid compounds characterized by small crystallite size, high porosity and relatively high surface area. The mixed oxide sorbents contain one Group IB, IIB or VIIB metal oxide such as copper, zinc or manganese and one or more oxides of Groups IIIA, VIB or VII such as aluminum, iron or molybdenum.

Abstract: A continuous process for the manufacture of a metal salt solution is described which provides more economical products with higher quality than current processes. The process is safer, both to operating personnel and to the environment, than currently used processes. The process comprises feeding an aqueous metal compound slurry, e.g., a metal oxide/hydroxide slurry and a mineral acid, e.g., nitric acid, and water to a reactor which includes a zone of extreme mixing and agitation, most preferably a cross-pipe reactor provided with an optional static in-line mixer. A cross-pipe reactor provides complete and efficient reaction by providing greater surface area, high agitation and a long reaction time.