Abstract: A method of manufacturing calcium phosphate using phosphorus in plants. The method comprising the steps of firstly slurrying raw material containing phosphorus, including plants particularly such as soybean, corn, oil meal of the rice bran and the like; adding one or more selected among oxide, hydroxide and carbonate of calcium to the slurry and mixing them; controlling Mg component derived from the raw material so that the Mg/Ca mole ratio is in the range of 0.25 or less; dehydrating and drying them; controlling pH of the slurry and 7.5 or higher and slowly heating them within the temperature range from 150.degree. C. to 650.degree. C. in the oxidation atmosphere to dissipate and remove carbon; and finally raising the temperature to burn them within the temperature range from 700.degree. C. to 1550.degree. C. in the oxidation atmosphere.

Abstract: A process for producing a calcium phosphate comprising the steps of (a) dissolving at least one member selected from the group consisting of calcium hydroxide and calcium oxide in water with at least one member selected from the group consisting of a sugar, a sugar alcohol, and a polyhydric alcohol; (b) and adding phosphoric acid to the solution obtained to precipitate a calcium phosphate.

Abstract: A process for the preparation of rapidly soluble DCP and TCP. The process comprises adding calcium to phosphoric acid, during continuous agitation, while regulating the pH and temperature. The resultant slurry is quickly dried. The TCP which is formed is rapidly soluble in an acidic aqueous solution, such as a dry beverage mix.

Abstract: A method of producing fluorapatite wherein predetermined amounts of calcium monohydrogen phosphate, calcium carbonate, and calcium fluoride are weighed, subjected to a mechanochemical action, and caused to react with one another in water. With this method, a fluorapatite having a uniform composition can be obtained without the accompaniment of by-products. A moisture sensitive resistor of the present invention can be obtained by sintering the fluorapatite produced in accordance with this method. This moisture sensitive resistor has a sufficiently low resistance corresponding to a humidity, and has substantially no hysteresis.

Abstract: This invention relates to the manufacture of hydroxylapatite in a through-solution process wherein monobasic calcium phosphate is reacted with a calcium hydroxide solution. In a preferred embodiment, an acidic premix is formed by reacting phosphoric acid and calcium hydroxide with high shear agitation in a first stage, and thereafter reacting the acidic premix with a saturated solution of calcium hydroxide also under high shear agitation in a second stage. The second stage reaction is carried out in an alkaline solution by carefully metering the acid premix into the calcium hydroxide solution whereby the pH of the solution is maintained above 11 until the reaction is near completion. It is particularly preferred to use a stoichiometric portion of calcium hydroxide in carrying out the reactions. After the hydroxylapatite precipitate is recovered, it may be sintered at a temperature between about 700.degree. C. and 1100.degree. C. for about 5 to 30 minutes to form a crystalline hydroxylapatite.

Abstract: The present invention relates to a process for preparing a calcium-phosphorus-apatite, essentially characterized by admixing a single solvent of water or an organic solvent compatible with water or a mixed solvent of water with an organic solvent compatible with water with calcium and phosphorus compounds soluble in said single or mixed solvent to prepare a raw material solution, and atomizing the raw material solution into a flame or a heating zone for effecting a thermal decomposition reaction thereof to form a calcium-phosphorus-apatite; a calcium-phosphorus-apatite obtained by the process and having novel characteristics; and the use of the calcium-phosphorus-apatite as a chromatographic packing material.

Abstract: A calcium-phosphate type hydroxyapatite which belongs to a series of hexagonal systems has unit lattice constants of 9.58.+-.0.08 .ANG. for the a axis and 7.00.+-.0.05 .ANG. for the c axis. Its Ca/P ratio is in the range of 1.50 to 1.90. It is for use as a column packing material for chromatographic separation of biopolymers. The hydroxyapatite is produced by firing it in the form of a gel or powder at a temperature of 400.degree. to 700.degree. C. As a gel the hydroxyapatite takes the form of a suspension or slurry. A powder is prepared by removing moisture from the hydroxyapatite in the gel form and then drying. Either gel or powder is fired by heating in the presence of oxygen or air at 500.degree. to 600.degree.0 C.

Abstract: A calcium-phosphate type hydroxyapatite for chromatographic separation is in the form of spherulites having a mean particle diameter of 0.5 to 50 .mu.m, preferably 1 to 10 .mu.m. The spherulites are each an aggregate mainly of acicular crystallites belonging to a series of hexagonal systems and having unit lattice constants of 9.58.+-.0.08 .ANG. for the a axis and 7.00.+-.0.05 .ANG. for the c axis. The hydroxyapatite is produced by granulating a calcium-phosphate type hydroxyapatite in the form of a gel and then firing the granular apatite at 400.degree. to 700.degree. C., preferably at 500.degree. to 600.degree. C. The firing is performed by heating the granules in the presence of oxygen or air for a given period of time.

Abstract: Process for production of desired phosphates from naturally occurring phosphates is characterized by treating naturally occurring phosphates under alkaline conditions to produce a material comprising trisodium and/or tripotassium orthophosphates, carbonating said material in solution, and recovering the desired phosphates from the carbonated solution. The desired phosphates include di- and mono-sodium orthophosphate; pentasodium tripolyphosphate; sodium metaphosphate and its polymers; tetrasodium pyrophosphate; ammonium phosphate; sodium ammonium hydrogen phosphate, magnesium ammonium phosphate; and the corresponding potassium salts thereof.

Abstract: An anti-corrosion coating and pigment therefore, the latter comprising the combination of condensed aluminum phosphate with a comminuted zeolite or silica and process for the preparation thereof.

Abstract: Porous spheres of calcium phosphate compound are produced by preparing an aqueous solution containing a water-soluble calcium salt, a calcium ion complexing agent, and a water-soluble phosphate, adjusting the pH of the aqueous solution, adding hydrogen peroxide to the aqueous solution, and heating the resultant mixture.

Abstract: A microfine .beta.-tricalcium phosphate powder is produced by mixing hydrogen calcium phosphate powder, calcium carbonate powder, and water in amounts calculated to give a slurry having a solids concentration in the range of 5 to 15% by weight and a CA:P atomic ratio in the range of 1:1.4.about.1.6 and subjecting the slurry to attrition.

Abstract: The present invention relates to a process for preparing a calcium-phosphorus-apatite, essentially characterized by admixing a single solvent of water or an organic solvent compatible with water or a mixed solvent of water with an organic solvent compatible with water with calcium and phosphorus compounds soluble in said single or mixed solvent to prepare a raw material solution, and atomizing the raw material solution into a flame or a heating zone for effecting a thermal decomposition reaction thereof to form a calcium-phosphorus-apatite; a calcium-phosphorus-apatite obtained by the process and having novel characteristics; and the use of the calcium-phosphorus-apatite as a chromatographic packing material.

Abstract: The process for producing microsized amorphous particles of a metal phosphate incorporates the steps offorming a solution of a metal alkoxide in an organic solvent,forming an aqueous phosphoric acid solution,introducing the alkoxide and the phosphoric acid solutions into a reactor vessel wherein the solutions are immiscible and forming two separate liquid phases with an interface,applying agitation to at least the region of the interface to promote a reaction between the metal alkoxide and said phosphoric acid at the interface,collecting the reaction product, andfiring it in an oxygen containing environment at a temperature sufficiently high to drive off the organic residue.

Abstract: Ultrapure silicon nitride precursor is made by: (a) continuously reacting liquid silicon halide (SiCl.sub.4) with an excess of liquid ammonia (NH.sub.3) (i) in the effective absence of contaminants, (ii) at a reaction situs in an inert atmosphere to form the silicon nitride precursor as a precipitate, and (iii) with a ratio of liquid ammonia to silicon halide (equal to or greater than 21 molar) effective to solubilize any gas reaction products; (b) providing a pressure differential to simultaneously and continuously withdraw a filtered portion of the excess liquid ammonia to leave the silicon nitride precursor precipitate in the reaction situs; and (c) adding ammonia to the excess of ammonia in said reaction situs to replace the withdrawn filtered portion of the liquid ammonia.The reaction is carried out with vigorous stirring of the liquid mixture and the atmosphere over the entire mixture is regulated to contain only ammonia vapor and nitrogen.

Abstract: The present invention relates to a granular product comprising a reaction product between magnesium oxide and phosphoric acid; this product exhibiting high solubility in neutral citrate solubility tests and the weight ratio of magnesium to phoshorous being smaller than 1.8:1.

Abstract: In a process for producing crystals in crystallographic point group 32 and corresponding to the comprehensive chemical formula APO.sub.4, wherein symbol A is a chemical element taken from the group Al and Ga, P is phosphorus and O is oxygen, from heated solutions of salts of group A in phosphorus acid, the application of acid concentrations within the range of 12.5 to 20 mol/l, solution temperatures within the range of 110.degree. to 190.degree. C. and total pressures within the range of prevailing static vapour pressure to 2.5 bar provides a simple, safe and cost-effective method of producing perfect, flawless crystals.

Abstract: This invention relates to the formation of a new solid material composed of calcium phosphates and to the reaction method for producing this material. The solid calcium phosphate material is created by chemically reacting calcium ion sources with phosphate ion sources in a molten state and cooling the reaction mixture to room temperature producing the solid material. Depending upon the ratio of components and the parameters of the heating reaction, the resulting material may be a smooth, non-porous material with exceptional hardness, or it may be a porous material. Both types of material can be shaped into desired configurations, such as artificial teeth.

Abstract: A process is provided for the recovery of one or more useful products including fertilizer, animal feed supplements, iron oxide, magnesia, salt, purified brine, and purified water from brines. The source of the brines can be oil and gas field wastes, seawater or effluent from a seawater desalination plant, or other inland brine sources. Iron and magnesium are initially precipitated from the brine. Then phosphoric acid is added to the brine followed by an alkaline agent to produce precipitates useful as fertilizer and animal feed supplements. The remaining salt in the brine may then be removed and recovered along with purified water.

Abstract: The invention is directed to inorganic phosphate aerogels and the method of preparing such inorganic phosphate aerogels which are characterized by high surface areas and high pore volume. The preparation comprises reacting an inorganic alkoxide or metal salt with a phosphate to form a gelled or colloidal material which is further treated with a fluid at or above its critical temperature and pressure to extract the solvent which is then dried to remove surface water.

Abstract: A fine particulate crystalline aluminum orthophosphate is obtained by reacting an aqueous phosphoric acid solution with an aluminum oxide under heating in an organic solvent which is incompatible with water.

Abstract: In a phosphate fluorescent substance including orthophosphate as a parent material and manganese as a main activator, said phosphate fluorescent substance has at least one of the following features (I) and (II): (I) The maximum intensity point in the glow curve is within the range of 200.degree.-400.degree. C. and (II) Ia/Ib is within the range of 0.6-3.0.

Abstract: A process for the recovery of phosphate values from a phosphate ore, wherein the ore is leached with a mixture comprising water, sulphur dioxide and an organic carbonyl compound; the leach liquor containing dissolved phosphate values and calcium hydroxysulphonate is separated from any gangue and other insoluble material; and the leach liquor is treated to recover therefrom a phosphate-rich product and at least part of the sulphur dioxide and the carbonyl compound; characterized in that the leaching is carried out under conditions such that substantially no calcium hydroxysulphonate is precipitated at the leaching stage.

Abstract: There are provided a novel sintered apatite body and a novel sintered apatite-mineral fiber material composite. The crystals of the sintered apatite have fine dense crystalline structures comprising needle-like fine crystals and are entangled together, whereby the mechanical properties of the sintered apatite body or composite are markedly enhanced. The sintered body and composite wherein the apatite is hydroxyapatite are useful for bioceramic uses. The sintered apatite body or composite is produced by baking an apatite material alone or in contact with a reinforcing mineral fiber material in the presence of water under pressure at a temperature lower than 1000.degree. C., and further at a temperature lower than the temperature causing deterioration of the fiber material in the case of the composite.

Abstract: A filler for filling in defects or hollow portions of bones to coalesce with the bone tissues is provided which comprises powders of a calcium phosphate compound having the apatite crystalline structure of each crystallite size of 400 .ANG. or larger and of each crystal grain size of 3 .mu.m or smaller, said calcium phosphate compound being represented by the following general formula of Ca.sub.m (PO.sub.4).sub.n OH (1.33.ltoreq.m/n.ltoreq.1.95), and said powders being fluidized or plasticized.

Abstract: A calcium-phosphorus apatite is obtained by reacting a calcium compound with a phosphorus compound under reflux in a reaction medium consisting mainly of an organic solvent and water.

Abstract: High purity berlinite is prepared by formation of an organoaluminum phosphate hydrogel in an organic solvent and subsequently hydrolyzing the hydrogel by reaction with water at pH less than or equal to 3.0. The berlinite is useful as a replacement for silicon-based quartz in electronic applications and in piezoelectric devices.

Abstract: This invention relates to hydroxyapatite, ceramic material, implant material and a process for preparing thereof. The ceramic material is hydroxyapatite ceramic having an excellent thermal stability.

Abstract: Aluminum orthophosphate is prepared by combining a source of phosphate ions with an aluminum salt to form a concentrated mass, combining with sufficient neutralizing agent to partially neutralize, and aging until gellation occurs. The resulting aluminum phosphate is particularly suited for use as a base for a chromium olefin polymerization catalyst.

Abstract: Aluminum orthophosphate is prepared by combining a source of orthophosphate ions with an aluminum salt to form a concentrated mass, gelling, and thereafter converting the resulting hydrogel to a xerogel by removing water. The resulting aluminum phosphate is particularly suited for use as a base for a chromium olefin polymerization catalyst.

Abstract: A filler for filling in defects or hollow portions of bones to coalesce with the bone tissues is provided which comprises powders of a calcium phosphate compound having the apatite crystalline structure of each crystal grain size of from 50 .orgate. to 10 microns and represented by the following general formula of Ca.sub.m (PO.sub.4).sub.n OH (1.33.ltoreq.m/n.ltoreq.1.95); and said powders being adapted for filling in a fluidized or plasticized state. A method of treating a bone with the filler is also provided wherein at least a portion of said filler is filled in to reach the bone-marrow cavity of said bone.

Abstract: Metallic phosphates are prepared by heating mixtures of BPO.sub.4 and a metallic oxide or salt.

Abstract: The invention is the production of crystalline tertiary magnesium phosphate octahydrate having uniform and perfect crystal shape. The process comprises adding a monomagnesium phosphate solution to a magnesium hydroxide slurry at a sufficient temperature and for a sufficient time to form the highly pure crystalline product within a specified pH range.

Abstract: Aluminum zinc phosphate hydrates or basic aluminum zinc phosphate hydrates are manufactured by reacting 1 mole of aluminum hydrogen phosphate with from 2.4 to 4 moles of zinc oxide, if necessary with the addition of up to 0.4 moles of alkali aluminate or the equivalent quantity of alkali hydroxide. A 50% by weight acidic aluminum hydrogen phosphate solution is preferably used for the reaction which is carried out at an elevated temperature in the range from 30.degree. to 80.degree. C. The aluminum zinc phosphate hydrates produced by the method are useful anti-corrosion pigments for use in paints.

Abstract: Crystalline alpha zirconium phosphate Zr(HPO4).sub.2.H.sub.2 O, which can selectively remove ammonia and heavy metal ions from solution by ion exchange, is made by forming a room-temperature solution of zirconyl chloride ZrOCl.sub.2 in hydrochloric acid and adding sodium fluoride; the pH is now at most 1.6, the zirconium concentration is about 0.1M and the molar ratio sodium:zirconium is 5:1. Then, with rapid mixing, this composition is added to 15M phosphoric acid H.sub.3 PO.sub.4 (molar ratio phosphate:zirconium at least 3:1). Zirconium phosphate is precipitated.

Abstract: Phosphosiderite, FePO.sub.4.2H.sub.2 O, is prepared in high yield from molten Fe(NO.sub.3).sub.3.9H.sub.2 O and H.sub.3 PO.sub.4 using a phosphosiderite seed for initiation of precipitation and crystallization.

Abstract: The present invention relates to a process for the oxidation of alkali metal phosphites to alkali metal phosphates at temperatures of between 400.degree. and 500.degree. C. To this end, alkali metal phosphites are employed in the form of an aqueous solution or suspension and, if necessary, the alkali metal : P atomic ratio in this feed material is adjusted to a ratio which at least corresponds to the atomic ratio desired for the final product.More particularly, the solution or suspension is spray-dried in a tower, in a single operational stage, by spraying in a flame zone. Starting material free from alkali metal phosphate and with an alkali metal : P atomic ratio equal to or greater than 3.5 is used for making a trialkali metal phosphate which is obtained in admixture with an alkali metal hydroxide. Starting material which contains from 25 to 45% by weight of alkali metal phosphate, calculated as phosphorus, based on their total phosphorus content, is employed for making alkali metal polyphosphates.

Abstract: Aluminum orthophosphate is prepared by combining a source of orthophosphate ions with an aluminum salt to form a concentrated mass, gelling, and thereafter converting the resulting hydrogel to a xerogel by removing water. The resulting aluminum phosphate is particularly suited for use as a base for a chromium olefin polymerization catalyst.

Abstract: Aluminum orthophosphate is prepared by combining a source of phosphate ions with an aluminum salt to form a concentrated mass, combining with sufficient neutralizing agent to partially neutralize, and aging until gellation occurs. The resulting aluminum phosphate is particularly suited for use as a base for a chromium olefin polymerization catalyst.

Abstract: A photosensitive material in the form of a silver and chlorine-containing polyphosphate which exhibits permanent visible darkening on exposure to ultraviolet or short wavelength visible light, is described.

Abstract: Hydroxyapatite is prepared by heating an aqueous suspension of brushite without boiling at a substantially neutral pH. In this way, hydroxyapatite having rosette-shaped crystals can be prepared, having good flow rate when packed in a column or good resolution between elution peaks.

Abstract: This invention relates to hydroxyapatite, ceramic material, implant material and a process for preparing thereof. The ceramic material is hydroxyapatite ceramic having an excellent thermal stability.

Abstract: Disclosed is a process for the preparation of lead compounds which comprises reacting lead monoxide according to the wet method with an inorganic acid or organic acid in the presence of hydroxylamine under such conditions that the initial pH value of the reaction system is not higher than 7.Lead monoxide according to the wet method has an excellent reactivity with an inorganic acid or organic acid, but it contains higher oxides such as lead dioxide and minium, which cause coloration in lead compound products. According to this process, this undesirable coloration can effectively prevented.

Abstract: Berlinite crystalline powder of uniform particle size and high purity is prepared by repeated thermal cycling to react a mixture of aluminum hydroxide or aluminum oxide and an excess of concentrated phosphoric acid in a sealed pressure vessel. The vessel is preferably held in a horizontal orientation and rotated about a longitudinal axis during the reaction. The product powder is useful in growing large single crystals that have surface acoustic wave applications. Crystalline powder of alpha-gallium orthophosphate may be prepared using the same apparatus and a similar procedure.

Abstract: A continuous process for producing hydroxyapatite which comprises a two-stage reaction in which pH control and reactant flow are carefully regulated.

Abstract: The invention relates to a process for making phosphorus-containing anticorrosive pigments having a size of at most 20 microns by reacting one or more compounds of magnesium, calcium, strontium, barium, zinc, aluminum, iron, chromium or manganese with an oxygen acid of phosphorus or its alkali metal or ammonium salts at temperatures within the range 10.degree. to 100.degree. C. More particularly pigments consisting to an extent of at least 90% of particles with a size between 0.05 and 8 microns are produced by introducing an aqueous suspension or solution of the reactants into a dispersing means rotating at a speed of 3000 to 10,000 rpm, reacting the reactants by intimately mixing them, and separating and drying precipitated pigment.

Abstract: Hydroxyapatite suitable for incorporation as a synthetic bone ash in a "bone" china body is produced by continuously contacting a stream of a slurry of hydrated lime with a stream of at least about 60% by weight phosphoric acid at an approximately stoichiometric ratio of 10 Ca(OH).sub.2 to 6 H.sub.3 PO.sub.4 and a temperature of from about 80.degree. to about 85.degree. C. at a controlled reaction mixture of pH of from about 9.0 to about 11.0 and then calcining at a temperature of at least 1,000.degree. C.

Abstract: The invention relates to a positive active material for an electric cell with a non-aqueous electrolyte. Said active material is constituted by an oxyphosphate whose formula is Cu.sub.n O.sub.p (PO.sub.4).sub.2,n being an integer greater than 3 and lower than or equal to 6 and p being equal to n-3. Application to lithium primary cells.

Abstract: Dental restorative compositions containing a mixture of Ca.sub.4 (PO.sub.4).sub.2 O and at least one different calcium phosphate.

Abstract: Compositions that are useful and unique as dental remineralizers and dental cements, as well as methods for their use, are disclosed. The compositions are mixtures of at least two sparingly soluble calcium phosphates that are present in excess and a dilute aqueous solution approximately saturated withThe invention described herein was made in the course of research partially supported by a grant from the National Institute of Dental Research.