Abstract: Processes for inhibiting scale produced during wet process phosphoric acid production by adding a scale-inhibiting amount of a reagent having a primary amine-containing polymer to at least one stage of a wet process phosphoric acid production process are provided herein, wherein said primary amine-containing polymer includes one or more organic moieties that reduce the polymer's solubility in an aqueous environment as compared to its native form, thereby reducing or preventing scale in the wet process phosphoric acid production process.

Abstract: The present invention includes a partially continuous countercurrent process for converting gypsum, by reaction with ammonium carbonate, to products of ammonium sulfate and calcium carbonate by introducing the reactants into reactors, mixing the reactants for a predetermined amount of time, employing a novel combination of countercurrent flows coupled with the reactors operated in a batch manner with process recycle of liquids, removing materials from the reactor and separating solids from solutions wherein no reactants are added during the removal process and thus the reactants have sufficient time to react and ensure the desired degree of reaction, yield and purity of product calcium carbonate and ammonium sulfate while minimizing the reaction time.

Abstract: Methods for preventing or reducing the formation of scale in a wet-process phosphoric acid production process by intermixing a water-soluble functional organic reagent with a phosphoric acid at one or more step of the phosphoric acid production process in an amount sufficient to prevent or reduce at least one species of scale are provided.

Abstract: A process for the preparation of amorphous aluminum phosphate or polyphosphate-based pigment by reacting aluminum phosphate and sodium aluminate is provided. The amorphous aluminum phosphate or polyphosphate is characterized by a skeletal density of less than 2.50 grams per cubic centimeter and a phosphorus to aluminum mole ratio of greater than 0.8. In one embodiment, the composition is useful in paints as a substitute for titanium dioxide.

Abstract: A method for the manufacture of concentrated phosphorous acid starting from pure P4O6 is disclosed. The P4O6 is hydrolyzed, preferably under stirring in water in the presence of a homogeneous Broensted acid catalyst while maintaining in the hydrolysis/reaction medium a pH below 5 whereby the free water level, at the completion of the hydrolysis, is in the range from 0 to 40%.

Abstract: A method for producing phosphoric acid, comprising attack in an aqueous medium of phosphated rock with sulfuric acid, with formation of a first dihydrate slurry suspended in an aqueous phase having a free P2O5 content between 38 and 50% and a free SO3 content of less than 0.5%, conversion of this first slurry by heating with recrystallization of the solubilized calcium sulfate giving rise to a second hemihydrate slurry, and separation in the second slurry between a production phosphoric acid and a hemihydrate cake, characterized in that it comprises during the attack, addition of a fluorine source in the first slurry in a content from 1% to 5% by weight of F relatively to the P2O5 contained in the phosphated rock.

Abstract: The present invention generally relates to processes for recovery of phosphorus values and salt impurities from aqueous waste streams. In particular, the present invention relates to processes for recovery of phosphorus values and salt impurities from aqueous waste streams generated in the manufacture of phospho-herbicides, including N-(phosphonomethyl)glycine and glufosinate.

Abstract: Phosphate depletion, a physiological condition commonly seen in certain patient populations, including alcoholics, malnourished, acutely ill patients, patients receiving parenteral nutrition, patients being re-fed after prolong fasting, and dialysis patients, requires intravenous supplementation when oral repletion is not feasible. This invention provides a method and pharmaceutical composition for therapeutic administration of pyrophosphate, instead of phosphate, for phosphate or pyrophosphate repletion. During hemodialysis or peritoneal dialysis significant removal of phosphate and pyrophosphate occurs. Pyrophosphate depletion predisposes patients to vascular calcification. This invention further provides a method and pharmaceutical composition for therapeutic administration of pyrophosphate for phosphate or pyrophosphate repletion by addition of pyrophosphate to hemodialysis or peritoneal dialysis solutions.

Abstract: A method for the manufacture of concentrated phosphorous acid starting from pure P4O6 is disclosed. The P4O6 is hydrolysed, preferably under stirring in water in the presence of a homogeneous Broensted acid catalyst while maintaining in the hydrolysis/reaction medium a pH below 5 whereby the free water level, at the completion of the hydrolysis, is in the range from 0 to 40%.

Abstract: Processes and reagents for inhibiting or eliminating scale formation during wet-process phosphoric acid production are provided and include adding to a wet-process phosphoric acid production stream a scale inhibiting amount of a reagent having an aliphatic or aromatic compound containing at least two hydroxy groups, and at least one amine.

Abstract: Methods for preventing or reducing the formation of scale in a wet-process phosphoric acid production process by intermixing a water-soluble functional organic reagent with a phosphoric acid at one or more step of the phosphoric acid production process in an amount sufficient to prevent or reduce at least one species of scale are provided.

Abstract: The present invention provides novel indole derivatives useful to inhibit cancer or sensitize cancer cells to chemotherapeutic agents, radiation or other anti-cancer treatments.

Abstract: The present invention provides a purification method of phosphoric acid, which includes bringing phosphoric acid containing arsenic into contact with hydrogen halide, thereby to remove the arsenic from the phosphoric acid, and a purification method of phosphoric acid, which includes bringing phosphoric acid containing arsenic into contact with hydrogen halide in the presence of a compound capable of generating hydrogen halide under acidic conditions. According to the method for purifying phosphoric acid of the present invention, a completely new method for removing arsenic in phosphoric acid is provided, which does not require a filtration or deaeration step or shows a great amount of residual sodium, unlike a sulfide coagulation method. This method is applicable to high concentration phosphoric acid, particularly polyphosphoric acid, and can be practiced at a low cost.

Abstract: The present invention is directed to a synthetic biomaterial compound based on stabilized calcium phosphates and more particularly to the molecular, structural and physical characterization of this compound. The compound comprises calcium, oxygen and phosphorous, wherein at least one of the elements is substituted with an element having an ionic radius of approximately 0.1 to 1.1 ?. The knowledge of the specific molecular and chemical properties of the compound allows for the development of several uses of the compound in various bone-related clinical conditions.

Abstract: Benzamidine derivatives of the following formula, analogs thereof and pharmaceutically acceptable salts thereof are provided. These compounds have an effect of inhibiting activated blood-coagulation factor X, and they are useful as agents for preventing or treating various diseases caused by thrombi or emboli.

Abstract: An improved method for making polyphosphoric acid from phosphoric acid includes the steps of introducing a first phosphoric acid feed stream into the top end of a packed column, introducing a second phosphoric acid feed stream into a stream of hot air to form a stream of hot air and acid, introducing the stream of hot air and acid into the bottom end of the column, and polymerizing phosphoric acid of the first and second phosphoric acid feed streams to make polyphosphoric acid. By-product phosphoric acids containing organic contaminants may be substituted for all or part of the phosphoric acid stream being introduced into the bottom end of the column to allow recovery of the phosphorus values of the by-product phosphoric acids.

Abstract: The invention provides novel &bgr;-lactamase inhibitors, which are structurally unrelated to the natural product and semi-synthetic &bgr;-lactamase inhibitors presently available, and which do not possess &bgr;-lactam pharmacophore. These new inhibitors are fully synthetic, allowing ready access to a wide variety of structurally related analogs. Certain embodiments of these new inhibitors also bind bacterial DD-peptidases, thus potentially acting both as &bgr;-lactamase inhibitors and as antibiotics.

Abstract: The invention provides novel &bgr;-lactamase inhibitors, which are structurally unrelated to the natural product and semi-synthetic &bgr;-lactamase inhibitors presently available, and which do not possess a &bgr;-lactam pharmacophore. These new inhibitors are fully synthetic, allowing ready access to a wide variety of structurally related analogs. Certain embodiments of these new inhibitors also bind bacterial DD-peptidases, thus potentially acting both as &bgr;-lactamase inhibitors and as antibiotics.

Abstract: The present invention is directed to a synthetic biomaterial compound based on stabilized calcium phosphates and more particularly to the molecular, structural and physical characterization of this compound. The compound comprises calcium, oxygen and phosphorous, wherein at least one of the elements is substituted with an element having an ionic radius of approximately 0.1 to 1.1 Å. The knowledge of the specific molecular and chemical properties of the compound allows for the development of several uses of the compound in various bone-related clinical conditions.

Abstract: A process for the manufacture of phosphorus (I) species, phosphorus (III) species, and lower hydrides of phosphorus from phosphorus (V) species is provided. Particularly, the present invention is directed to a process for the preparation of P(I) species, P(III) species, and lower hydrides of phosphorus, wherein the process comprises contacting a P(V) species with a reducing agent in the presence of a catalyst effective to promote reduction of the P(V) species by reaction with a reducing agent. Preferably the reducing agent comprises hydrogen.

Abstract: Benzamidine derivatives of the following formula, analogs thereof and pharmaceutically acceptable salts thereof are provided. These compounds have an effect of inhibiting activated blood-coagulation factor X, and they are useful as agents for preventing or treating various diseases caused by thrombi or emboli.

Abstract: The invention encompasses compounds represented by formula I: as well as compositions and methods of treatment. The compounds are inhibitors of the PTP-1B enzyme.

Abstract: The present invention is directed to a synthetic biomaterial compound based on stabilized calcium phosphates and more particularly to the molecular, structural and physical characterization of this compound. The compound comprises calcium, oxygen and phosphorous, wherein at least one of the elements is substituted with an element having an ionic radius of approximately 0.1 to 1.1 Å. The knowledge of the specific molecular and chemical properties of the compound allows for the development of several uses of the compound in various bone-related clinical conditions.

Abstract: A process for the preparation of an oxyacid of phosphorus comprising contacting elemental phosphorus with water in the presence of a catalyst effective to promote oxidation of phosphorus by reaction with water. The use of a noble metal catalyst such as Pd under moderate agitation and low severity conditions is effective for the preparation of P(III) oxyacid in high selectivity. Other suitable catalysts may comprise, for example, other Group VIII metals (particularly other platinum metals); oxides, salts, phosphides, and/or coordination compounds of Group VIII metals; Group IB metals; and/or oxides, salts, phosphides, and/or coordination compounds of Group IB metals. Various apparatus and process as schemes for the preparation of phosphoric and phosphorous acid are also disclosed.

Abstract: The invention relates to a process for producing a unique phosphation reagent and to a simple, single-stage process utilizing is reagent to produce alkyl phosphate esters having high monoalkyl phosphate content in combination with low dialkyl phosphate, trialkyl phosphate, phosphoric acid and residual alcohol.

Abstract: Disclosed is a method of making phosphorous acid or hypophosphorous acid by reacting hydrogen chloride with a sodium phosphite or a sodium hypophosphite, respectively, in the presence of water to precipitate sodium chloride crystals and form the acid. The acid is separated from the sodium chloride crystals and can be passed through an anion exchange column that is preferably loaded with phosphite or hypophosphite ions, respectively, to remove residual chloride ions.

Abstract: There is disclosed a process for the controlled hydrolysis of phosphorus trichloride which avoids the formation of lower oxides of phosphorus, phophines and diphosphines wherein phosphorus pentachloride is added to the phosphorus trichloride from about 20 to about 90 percent by weight of the phosphorus trichloride and then water in the form of finely divided droplets is added over the surface of the phosphorus trichloride while the temperature is controlled to below about 80.degree. C.

Abstract: In a continuous process for the preparation of phosphorous acid with simultaneous production of hydrochloric acid, a reaction zone is provided which is in open communication with a first scrubbing zone. A portion of the reaction product is recycled from the bottom of the reaction zone into the top of the scrubbing zone and phosphorous acid is removed from the circulation. Hydrogen chloride gas escaping from the top of the first scrubbing zone is brought into contact, in a cooled, second scrubbing zone, with an overstoichiometric amount of water. Hydrochloric acid is obtained which is passed as starting material into the reaction zone or into the top of the first scrubbing zone. The external cooling of the second scrubbing zone is controlled such that the temperature in the reaction zone is kept constant at a desired value between 90.degree. and 130.degree. C. without adding any external cooling or heating energy. Pure hydrochloric acid is recovered in an absorption zone.

Abstract: Phosphorous acid is made by a continuous recycling process from a mixture of phosphorous and hydrochloric acids, comprising:(i) continuously recycling the mixture in a loop apparatus;(ii) adding water to and passing phosphorus trichloride into said recycling mixture so as to generate a condition of turbulent flow at the point of contact of the phosphorus trichloride and the recycling mixture, whereby a reaction product, comprising an aqueous solution of phosphorous and hydrochloric acids as a continuous liquid phase and gaseous hydrogen chloride as gas bubbles of disperse phase, is produced;(iii) separating said gaseous hydrogen chloride;(iv) cooling said reaction product; and(v) recycling at least a portion of said reaction product and repeating steps (ii), (iii) and (iv) thereon to produce a more highly concentrated solution of phosphorus acid.

Abstract: The phosphorus values from waste phosphoric acid containing organic contaminents such as wastes obtained in the manufacture of quinacridone pigments can be recovered in purified form by hydrolyzing phosphate esters, removing any formed alcohol, dissociating any amine phosphates and separating any free amine. The phosphorus values can be recovered in a purified form as phosphate salts.

Abstract: Phosphorous acid is formed by gaseous phase oxidation of phosphorus with water vapour to form predominantly P.sub.2 O.sub.3 and dissolving the P.sub.2 O.sub.3 so-formed in water. The P.sub.2 O.sub.3 also can be recovered as the product by quenching the P.sub.2 O.sub.3 to a stable temperature using an inert cooling medium rather than water. Oxygen also may be used in conjunction with the water vapour. Sufficiently rapid quenching of reaction products may result in the formation of red amorphous phosphorus from unreacted phosphorus.

Abstract: The purification of phosphorous acid which is formed in halogenations of hydrocarbon derivatives using phosphorus trihalides is carried out in the context of preparing phosphorous acid in a reaction zone by reacting a mixture of phosphorus trichloride and water which has been finely divided by means of steam at temperatures between 150.degree. and 200.degree. C. in the gas phase. In this process, the liquid reaction product drains into a concentrating evaporation zone which has a downstream first separation zone. Inert gas is introduced to the lower part of the first separation zone. A melt is withdrawn from the first separation zone into a crystallizing zone. The waste gases from the reaction zone are treated with a washing liquid in a second separation zone before being passed into the atmosphere. The washing liquid used is an aqueous solution of never-purified phosphorous acid, which can have been prepurified by hydrolysis and stripping.

Abstract: A two-stage oxidation/reduction process for preparing commercially valuable, color enhanced and stabilized low viscosity wet process phosphoric acid is provided which yields improved acid that can be concentrated to superphosphoric acid and/or converted to high quality liquid fertilizer by reaction with ammonia, all without reversion to black color or excessive sludge formation in the fertilizer. The preferred process involves initially oxidizing a starting black acid having a 58-72% P.sub.2 O.sub.5 concentration by addition of an oxidizing agent such as NH.sub.4 NO.sub.3 with heating and agitation until the oxidized acid exhibits an EMF of greater than about 700 mv as compared with a 600 mv standard; the oxidized acid is then subjected to a reduction step to lower the valence of metallic impurities, by aging and/or adding reducing agents such as ferrous iron compounds to the acid.

Abstract: The calcium content of high purity concentrated phosphoric acid is reduced to not more than about 2 ppm by contacting the acid with a strong cation exchange resin.

Abstract: A process for the concentration of phosphoric acid by evaporation under vacuum in two stages to produce superphosphoric acid, the pressure inside the exchanger is kept equal to or greater than 0.35 bar higher than that in the evaporator vessel.

Abstract: Processes for the preparation of phosphoric acid, such as merchant phosphoric acid, and for the provision of phosphoric acid suitable for the preparation of ammonium phosphates, are disclosed. Such processes comprise providing a source stream of phosphoric acid comprising more than about 30% P.sub.2 O.sub.5, said source stream having impurities, and removing from the source stream a minor proportion, 20% or less, to form a treatment stream. The level of impurities in the treatment stream is reduced employing any of the means known to those skilled in the art, especially solvent extraction. At least a portion of the treated treatment stream is combined with the balance of the source stream to form a product stream. The treated treatment stream and source stream are proportioned so as to render the product stream less susceptible to post-precipitation than the source stream.

Abstract: Appreciable inorganic impurities and organic matter are removed from impure phosphoric acid, particularly wet-process phosphoric acid, by pyrolysis of a mixture containing the raw acid and porous carbonaceous matter, including carbohydrates and chars, then leaching the pyrolyzed residue therefrom with a suitable solvent such as water to extract the purified phosphoric acid.

Abstract: Phosphoric acid containing organic contaminants, such as phosphoric acid recovered from a thiophenol process, is treated to recover usable acid by conducting a hot separation of the contaminated acid into acidic and organic phases, removing the organic phase, preheating the acidic phase, stripping the latter with steam and removing any remaining organic contaminants from the stripped acid.

Abstract: The disclosure relates to a process for removing nitrogen dioxide from off-gas. To this end, the disclosure provides for the off-gas to be intimately contacted with a suspension consisting of red phosphorus and a liquid being inert with respect to red phosphorus, e.g. water.

Abstract: The invention is directed to a process for recovering elemental phosphorus values from phosphorus-containing waste materials. The process comprises reducing the size of the solid particulate materials of the sludge and forming a uniform homogenous sludge which is filtered through a high-pressure thin-cake filter resulting in a filtrate high in phosphorus values.The invention also discloses a pump retrieval means for retrieving the sludge from contaminated disposal areas and a preconditioning dewatering means for thickening and clarifying the sludge prior to comminuting the solids contained therein and filtrating to recover the phosphorus values contained therein.

Abstract: An improved process is provided for preparing highly purified phosphorus acid from industrial waste materials which are produced as by-products from the manufacture of sodium hypophosphite. Such industrial waste materials contain substantial quantities of calcium phosphite, and appreciable quantities of various metals such as iron, magnesium, aluminum and arsenic. The process of the present invention comprises, in a preferred embodiment thereof, reacting a slurry of said waste materials with sodium carbonate to produce calcium carbonate as a precipitate and a solution of sodium phosphite. The sodium phosphite solution is then passed through a cation ion exchange resin in the hydrogen form to produce a highly purified phosphorus acid product having significantly reduced quantities of metallic impurities.

Abstract: A process for the preparation of phosphorous acid from phosphites contained in industrial wastes, wherein the waste material is dissolved in an aqueous solution of phosphorous acid and reacted with a strong mineral acid that will remove the cation of the phosphite producing phosphorus acid. An alternative method for preparation is the passage of the solution of phosphite in phosphorus acid through a cation ion exchange resin to produce phosphorous acid. A typical industrial waste containing phosphites is the waste that occurs from the process of manufacturing sodium hypophosphite.

Abstract: Ultraphosphoric acid containing a phosphorus to hydrogen ratio of greater than 1 can be prepared by bringing together in a reaction zone elemental phosphorus and a sufficient amount of oxygen in a free-oxygen containing gas to form phosphorus pentoxide, and a sufficient amount of water to form ultraphosphoric acid. The mole ratio of water to phosphorus pentoxide is maintained less than 1:1. Heat is removed from the product stream of the reaction zone to condense at least some of the ultraphosphoric acid which is then collected. In the preferred embodiment, a heat exchange fluid such as pressurized water is circulated through a cooling coil positioned to remove heat from the product stream of the reaction zone. The ultraphosphoric acid can be combined with water to provide polyphosphoric acid.

Abstract: The direct reaction of elemental phosphorus acid catalyzed by hydroiodic acid produces orthophosphorus acid free of orthophosphoric acid and phosphine free of diphosphine.

Abstract: Polyphosphoric acid is dearsenicated by placing the polyphosphoric acid in a reactor; adding a phosphorus oxo-compound containing phosphorus in the monovalent or trivalent electropositive oxidation stage; heating the resulting mixture to effect disproportionation of the phosphorus oxo-compound; and removing the resulting off-gas having arsenic therein.

Abstract: Phosphorous acid is produced from PCl.sub.3 and water in an apparatus, the essential parts of which include a reactor and an evaporator, which are connected together by means of a conduit running from the bottom of the reactor to the head of the evaporator. The evaporator communicates with the lower end of a separator of which the upstream end terminates in an off-gas outlet. More particularly, the downstream end of the evaporator is connected to a stripping column which is provided with an off-gas outlet opening into the off-gas outlet associated with the evaporator.

Abstract: The present invention is directed to a synthetic biomaterial compound based on stabilized calcium phosphates and more particularly to the molecular, structural and physical characterization of this compound. The compound comprises calcium, oxygen and phosphorous, wherein at least one of the elements is substituted with an element having an ionic radius of approximately 0.1 to 1.1 ?. The knowledge of the specific molecular and chemical properties of the compound allows for the development of several uses of the compound in various bone-related clinical conditions.