Abstract: Hexagonal phosphorus pentoxide of diminished reactivity is made by burning liquid yellow phosphorus with a mixture of dry air and pure oxygen inside a combustion zone with the resulting formation of a gas stream containing phosphorus pentoxide; next, the gas stream coming from the combustion zone is passed initially through an intermediary zone indirectly cooled by means of fluidized matter and then through a condensing zone fitted with an immersion tube indirectly cooled by means of fluidized matter; the gas stream is passed through the immersion tube at a mean temperature of 450.degree. to 600.degree. C. and allowed to remain in the immersion tube over a period of 2 to 5 seconds.

Abstract: Phosphorus mud and other phosphorus-containing waste materials are processed to remove water and phosphorus and to leave a solid mass which is safe for disposal. The phosphorus mud is heated to boil off the water and then to boil off yellow phosphorus, which is subsequently condensed. The residual phosphorus then is removed mainly by burning off in air along with some volatilization, so as to increase the recovery rate of solids from the waste material, when compared to removal of residual phosphorus by volatilization under nitrogen. A significant improvement in processing rate is achieved at the expense of a loss of a minor amount of recoverable phosphorus.

Abstract: A process for purifying a gaseous mixture comprising arsine, phosphine, ammonia, and/or inert gases, to remove Lewis acid and/or oxidant impurities therefrom, comprising contacting the mixture with a scavenger including a support having associated therewith an anion which is effective to remove such impurities, such anion being selected from one or more members of the group consisting of: (i) carbanions whose corresponding protonated compounds have a pK.sub.a value of from about 22 to about 36; and (ii) anions formed by reaction of such carbanions with the primary component of the mixture.

Abstract: This disclosure involves a process for treating wet phospho-gypsum, a by-product from wet phosphoric acid manufacture, to remove fluorine values so as to make the sulfur values in the phospho-gypsum usable in making sulfuric acid in a contact sulfuric acid plant. The process involves drying the phospho-gypsum at 400.degree.-600.degree. C. to vaporize the fluorine values, the P.sub.2 O.sub.5 values and water and reacting the hot vapors with lime or limestone to remove the fluorine values as fluorspar. The P.sub.2 O.sub.5 values are subsequently condensed and used in a phosphoric acid plant. The dry phospho-gypsum is heated to 1200.degree.-1250.degree. C. under reducing conditions to produce SO.sub.2 gas and siliceous lime. The SO.sub.2 is then passed through a lime or limestone scrubber to eliminate any remaining fluorine values, dried and utilized in a contact sulfuric acid plant.

Abstract: Wet process phosphoric acid is freed from heavy metal ions, especially from ions of cadmium, copper, mercury, lead and arsenic and optionally also from organic compounds and sulfuric acid. To this end, the phosphoric acid is contacted with a diorganyldithiophosphoric acid ester and an adsorbent, if desired. Prior to or after said treatment with the ester, the phosphoric acid is admixed with a reductant. The adsorbent, if any is used alone or in combination with an alkaline earth metal compound soluble in phosphoric acid.

Abstract: Heat is recovered from the phosphorus combustion chamber of a furnace phosphoric acid plant by placing in the combustion chamber a heat exchange surface having a protective meta acid coating thereon. Pressurized water can be used as a heat exchange fluid.

Abstract: The reactivity of phosphorus pentoxide is reduced and its flow behavior improved. To this end, phosphorus pentoxide in the form of its hexagonal modification is annealed over a period of 0.5 to 8 hours at temperatures of 200.degree. to 390.degree. C.

Abstract: Aqueous phorphoric acid solutions are produced by contacting an elemental phosphorus-containing material with an oxygen-containing gas, while both are finely divided and well mixed together in a reactor vessel, while the phosphorus-containing material is otherwise protected from direct contact with oxygen in the atmosphere by being blanketed with a protective aqueous layer, and removing and recovering the heat generated in the reactor vessel (e.g., by means of a heat exchanger) due to the contact between the oxygen in the oxygen-containing gas and the elemental phosphorus in the elemental phosphorus-containing material. The technique is useful for the production of phosphoric acid from substantially pure elemental phosphrous.

Abstract: In the process of purifying yellow phosphorus by treating liquid yellow phosphorus with active carbon and separating the purified phosphorus from the spent active carbon containing adhering phosphorus, the spent active carbon is mixed with sufficient liquid phosphorus to form a slurry which is pumped to a disposal zone. The disposal zone is preferably a phosphorus furnace.

Abstract: Processes are disclosed for recovering solid wastes containing elemental phosphorus. The wastes may cause serious environmental problems at phosphorus furnaces because elemental phosphorus is toxic to marine animals. Recovery of the wastes was considered for the following.1 At phosphorus furnace plants making phosphoric acid as one of the products, when the objective is to produce only high-quality phosphoric acid.2. At phosphorus furnace plants making elemental phosphorus as a final product, and the objective is to produce only high-quality phosphorus.3. At plant sites where neither phosphoric acid nor phosphorus is produced.The processes include recycling the wastes to phosphorus furnaces. All of the phosphoric acid produced in 1 can be highly concentrated with low impurities content. In 2, all the low-quality phosphorus is recycled to the phosphorus furnaces and all the product is high grade. In 3, phosphorus furnaces are not available at the plant site and recycling the solid wastes is impractical.

Abstract: There is disclosed a process for the recovery of the heat values produced during the combustion of phosphorus to phosphorus pentoxide. The disclosed process dries ambient air to produce dry air, and combusts elemental phosphorus in said dry air in at least one fluid bed having in intimate contact therewith steam generating means containing steam generating fluid.

Abstract: A demolition agent for brittle materials which is prepared by pulverizing a quick lime clinker including 0.5 to 10.0% by weight of phosphorus components in terms of P.sub.2 O.sub.5.

Abstract: This disclosure concerns an improved phospho-gypsum recovery process in which phospho-gypsum waste product and coke are first heated to remove moisture, some SO.sub.2 and other vaporous matter, then heated to a higher temperature in a reducing atmosphere to remove and separately recover SO.sub.2, then further heated in an oxidizing atmosphere to about 1200.degree. to 1250.degree. C. to remove any unreacted carbon and calcium sulfide before entering an electric furnace. The disclosure also concerns passing the gas stream from the condenser-heat exchanger over the clinker from the electric furnace to scrub SO.sub.2 from said gas stream. The essence of the invention is the unique absorber system used to remove any and all remaining fluorine in the gases from the calciner/furnace. If not removed, the fluorine will severely harm the catalyst used in the contact sulfuric acid plant to which the gases are sent for recovery of sulfur values.

Abstract: The disclosure relates to a process for making phosphorus pentoxide by subjecting elemental yellow phosphorus to combustion with dried air inside a steel-made combustion chamber with utilization of the reaction heat for the production of energy.

Abstract: The disclosure relates to a process for making phosphorus pentoxide by subjecting elemental yellow phosphorus to combustion with dried air inside a steel-made combustion chamber with utilization of the reaction heat for the production of energy. To this end, the disclosure provides for the combustion to be effected inside a combustion chamber of which the walls are arranged so as to form a cooling system with cavities therein; for a liquid or liquid/steam-mixture as a heat carrier abstracting the reaction heat to be circulated through the cooling system, the liquid or liquid/steam-mixture assuming an increased temperature being preferably so circulated under increased pressure; for steam formed in the cooling system to be continuously taken therefrom; for an equivalent proportion of fresh liquid to be introduced into the cooling system; for hot P.sub.2 O.sub.

Abstract: New compositions of matter which are halogenated derivatives of borates are disclosed which are catalytically active in the polymerization of halogenated phosphazene trimers and other oligomers are disclosed.

Abstract: The disclosure relates to a process for making alkali metal hypophosphite solutions by reacting yellow phosphorus with an aqueous solution of an alkali metal hydroxide and/or carbonate. The disclosure provides more particularly for an aqueous hydrogen peroxide solution to be added to the mixture obtained by reacting the phosphorus with the alkali metal compound solution specified.

Abstract: Waste heat is recovered during the production of phosphorus pentoxide by a process comprising the combustion of phosphorus and the passing of the combustion gases through a fluid bed, wherein the solids making up the fluid bed are utilized to recover heat values derived from the process by contacting the same with water to produce steam.

Abstract: In a process for producing a defluorinated product containing calcium, sodium and phosphorus, by calcination of a mixture of phosphate rock, with caustic soda, phosphoric acid and water, an improvement comprises maintaining the amount of phosphoric acid in the mixture such that the ratio of phosphorus in percentage by weight on a dry basis in said mixture-to-the phosphorus desired in percentage by weight in the calcined product is substantially equivalent to the ratio of the calcium in percentage by weight on a dry basis in the mixture-to-the calcium in percentage by weight in the calcined product. The process is especially useful where the phosphate rock has a bone phosphate of lime analysis of about 73% or less (e.g., about 71.5%), and also where the caustic soda is added to a mixture of phosphate rock and phosphoric acid prior to the addition of water.

Abstract: A process for producing phosphorus pentoxide from phosphate ore includes the mixing and formulation of a feed mixture of phosphate ore with lime and solid carbonaceous material in amounts to produce a feed mixture having a CaO/SiO.sub.2 mole ratio greater than about 8.0. This mixture is formed into pellets which are then exposed to radiation eminating from an oxidation zone, preferably within a rotary type kiln, in order to heat the pellets to a temperature sufficient to reduce the phosphate by reaction with the solid carbonaceous material to form elemental phosphorus vapor without substantial melting of the pellets. Sufficient oxygen-containing gas is provided to cause oxidation of the elemental phosphorus vapor within the oxidation zone to produce phosphorus pentoxide.

Abstract: This disclosure concerns a process for treating phospho-gypsum waste product from the wet process method of making phosphoric acid including the steps of water washing the phospho-gypsum to remove all but an acceptable level of fluorine before the phospho-gypsum is calcined. The process allows the use of high sulfur coal for the production of steam if desired for use in the overall process. The process also allows for production of SO.sub.3 from part of the phospho-gypsum in an electric furnace to enrich the SO.sub.2 stream for making sulfuric acid.

Abstract: A process is disclosed for the purification of trichlorosilane and other silicon source materials. Trace impurities of boron and phosphorous are removed from trichlorosilane or dichlorosilane by reacting small amounts of oxygen with the trichlorosilane or dichlorosilane at a temperature between about 60.degree. C. and 300.degree. C. The oxygen reacts with the Si--H bond in HSiCl.sub.3 or H.sub.2 SiCl.sub.2 to form a "SiOH" species which in turn complexes impurities such as BCl.sub.3 or PCl.sub.3 present in the chlorosilane. Purification of the chlorosilane is then easily accomplished during a subsequent distillation step which separates the purified chlorosilane from the less volatile complexed boron or phosphorous compounds.

Abstract: A process for producing phosphorus pentoxide from phosphate ore includes the steps of mixing phosphate ore containing silica with solid carbonaceous material and a silica fluxing agent to form a feed mixture and thereafter forming the feed mixture into pellets. Alternatively, pellets may be formed using phosphate ore containing silica and carbonaceous material which are then coated with a silica fluxing agent. The pellets are heated by exposure to radiation eminating from an oxidation zone within a kiln to a temperature enabling the silica fluxing agent to promote melting of the silica proximate to surface areas of the pellet in order to seal internal portions of the pellet from the oxidizing zone and thereby reduce premature oxidation of the carbonaceous material in the pellet. Thereafter the pellets are heated to a temperature sufficient to reduce the phosphate in the pellets by reaction with the solid carbonaceous material to form elemental phosphorus vapor.

Abstract: A process for producing phosphorus pentoxide from phosphorus ore includes formation of a feed with a phosphate ore, silica and solid carbonaceous material in amounts to produce a feed mixture having a CaO/SiO.sub.2 mole ratio of less than about 0.5. The feed mixture is formed into agglomerated feed particles and the particles are heated by exposure to radiation eminating from an oxidation zone to a temperature sufficient to reduce the phosphate by reaction from the solid carbonaceous material to form elemental phosphorus vapor without substantial melting of the agglomerated feed particles. Sufficient oxygen-containing gas is provided to cause oxidation of the elemental phosphorus vapor within the oxidation zone to produce phosphorus pentoxide.

Abstract: A multiple-stage thermal beneficiation process for phosphate ores which comprises calcining a phosphate ore in a first stage at a temperature sufficient to destroy substantial quantities of organic impurities in the phosphate ore but not so high as to cause excessive sulfide formation; followed by the calcining of the product from the first stage in a second stage at a temperature at which an additional amount of organic carbon impurities are destroyed but at a temperature which does not detrimentally reduce the surface area of the phosphate ore.

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: The invention relates to process for making phosphorus pentoxide by subjecting elementary phosphorus to a combustion reaction with the aid of air, the reaction heat being utilized for the production of energy. To this end, the invention provides for the phosphorus to be subjected to combustion with dry air containing, per m.sup.3, 5 g down to 0.01 g of water, inside a combustion chamber of which the metallic walls are arranged so as to form a cooling system with cavities therein and for a liquid and liquid/steam-mixture, respectively, to be circulated through the cooling system under pressure within the range 1 to 150 bars, the liquid or mixture assuming a temperature of more than 150.degree. C. up to 500.degree. C. Steam which is formed in the cooling system is continuously taken therefrom and replaced by an equivalent proportion of fresh liquid.

Abstract: A process for producing hypophosphorous acid (H.sub.3 PO.sub.2) by reacting, in the absence of a catalyst and under an acidic condition, phosphine with an aqueous solution of hydrogen peroxide to produce an acid solution. The acid solution is then contacted with an non-transition metal hydroxide, oxide or carbonate, e.g. sodium hydroxide, to produce a product composition containing a hypophosphite, e.g. sodium hypophosphite (NaH.sub.2 PO.sub.2.H.sub.2 O). The process of this invention finds particular utility in processes of the type wherein phosphorus is reacted with an aqueous non-transition metal hydroxide composition, e.g. an aqueous suspension of a sodium hydroxide and calcium hydroxide, to produce a hypophosphite and byproduct phosphine. The process of this invention converts a substantial portion of the byproduct phosphine to hypophosphite.

Abstract: Phosphorus in vapor form and phosphanes are separated from gas mixtures which consist of carbon monoxide, with or without hydrogen, nitrogen and steam. Concerned are more particularly the off-gases of phosphorus-producing furnaces. To this end, the gas mixture is admixed with at least the stoichiometric amount of oxygen and/or of oxygen-containing gases necessary to achieve conversion of the total phosphorus contained in the gas mixture to oxidation level V. The resulting mixture is introduced into a reaction zone maintained at a temperature within the range 200.degree. to 700.degree. C. and allowed to remain therein over a period of 0.5 to 20 seconds. Resulting phosphorus-V compounds are finally separated from the gas mixture.

Abstract: A process for reducing phosphate ore includes beneficiating phosphate ore to reduce alumina impurities while allowing fluoride impurities to remain in the beneficiated ore, mixing beneficiated ore with solid carbonaceous material to form a porous bed of agglomerated feed and heating the porous bed in a rotary-type kiln to produce elemental phosphorus and carbon monoxide. The elemental phosphorus may be burned within the kiln to provide heat to the porous bed and an inert gas may be purged through the porous bed to drive the reaction between the phosphate ore and the solid carbonaceous material towards complete reduction of the phosphate ore by removal of carbon monoxide from the porous bed.

Abstract: A process for producing phosphorus pentoxide from phosphate ores in a rotary-type kiln includes heating, by exposure to a flame, a porous bed comprising phosphate ore and solid carbonaceous material to a temperature sufficient to reduce the phosphorus pentoxide to phosphorus vapor. The phosphorus vapor is oxidized in an oxidation zone disposed over the porous bed to heat the porous bed. An inert gas is used to purge the porous bed of carbon monoxide formed during the reduction reaction to drive the reduction reaction more rapidly toward complete reduction of the phosphorus pentoxide and to inhibit oxidation of the phosphorus vapor and carbonaceous material within the porous bed.

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: Phosphosilicate compositions are disclosed for treating foundry molds and like products to enhance mold strength and refractoriness. The phosphosilicates, characterized more specifically as silicyl metaphosphates, may be used in combination with select refractory aggregates and other additives to form mold surface treating compositions, or may be combined directly with foundry sand or other comminuted refractory material for compacting into a mold form.

Abstract: Intimate contacting of plural, physically disparate phases is achieved by establishing a current of axially extending, axially symmetrical helical flow of a first phase; separately establishing a current of coaxially extending, rectilinear flow of a physically disparate second phase, the currents of said first and said second phases being maintained physically separated from each other; circulating and directing said currents which comprise the plural phases to a zone of restricted flow passage with respect to said helical flow, whereby said plural currents converge and are intimately, homogeneously admixed and whereas such zone of convergence the momentum of the first phase helical flow is at least 100 times greater than the momentum of the second phase, coaxial rectilinear flow; and thence abruptly changing the velocity field of at least one of said plural phases, while at the same time maintaining the general direction of flow of said admixed plural phases, and whereby phase separation of the product of ad

Abstract: A process for producing hypophosphorous acid (H.sub.3 PO.sub.2) by reacting, in the absence of a catalyst and under an acidic condition, phosphine with an aqueous solution of hydrogen peroxide to produce an acid solution. The acid solution is then contacted with an non-transition metal hydroxide, oxide or carbonate, e.g. sodium hydroxide, to produce a product composition containing a hypophosphite, e.g. sodium hypophosphite (NaH.sub.2 PO.sub.2.H.sub.2 O). The process of this invention finds particular utility in processes of the type wherein phosphorus is reacted with an aqueous non-transition metal hydroxide composition, e.g. an aqueous suspension of a sodium hydroxide and calcium hydroxide, to produce a hypophosphite and byproduct phosphine. The process of this invention converts a substantial portion of the byproduct phosphine to hypophosphite.

Abstract: Intimate contacting of plural, physically disparate phases is achieved by establishing a current of axially extending, axially symmetrical helical flow of a first phase; separately establishing a current of coaxially extending, rectilinear flow of a physically disparate second phase, the currents of said first and said second phases being maintained physically separated from each other; circulating and directing said currents which comprise the plural phases to a zone of restricted flow passage with respect to said helical flow, whereby said plural currents converge and are intimately, homogeneously admixed and whereat such zone of convergence the momentum of the first phase helical flow is at least 100 times greater than the momentum of the second phase, coaxial rectilinear flow such as to effect atomization via transfer of momentum, and ultimately effecting phase separation of the product of admixture.

Abstract: Hexagonal phosphorus pentoxide is made in an apparatus comprising a combustion chamber (1) which has a plurality of cooling pipes (10) disposed at its inside wall and is connected through a gas cooler (3) to a condensation chamber (4), the gas cooler (3) comprising a system of cooling pipes (5) which terminate, similarly to an open immersion tube, above the bottom portion of the condensation chamber (4), whose walls are provided with a cooling device (6).

Abstract: A process for the treatment of incinerated sewage sludge ash containing silicic compounds and metal values including phosphorus and at least one precious metal comprises leaching the ash in an acid solution in a first leach to dissolve phosphorus. The leach solution is separated from the undissolved residue, which is then treated to recover at least one precious metal.

Abstract: A method for removing small concentrations of phosphine contained in a carbon monoxide gas mixture by preferentially oxidizing the phosphine, in which the phosphine is oxidized with air at a temperature of from 500.degree. C. to 800.degree. C. to form phosphorus pentoxide, which is recovered from the gas mixture preferably as phosphoric acid.

Abstract: The process of treating insoluble phosphate ore in the form of calcium phosphate, such as phosphate rock or bone phosphate, at near ambient conditions with sulfur trioxide or sulfuric acid as reactants in the presence of a liquid anhydrous dispersion media of, preferably, sulfur trioxide, sulfur dioxide, or their mixtures in liquid form so that the contacting of the ore is made in the form of an anhydrous slurry, to make the phosphorous content available as a nutrient or as phosphoric acid, and subsequently separating the dispersion media from the contacted ore preceding aqueous contact or extraction of the phosphorous constituent. The presence of sulfur dioxide in the anhydrous dispersion media is desirable to minimize operational difficulties associated with the proximity of the vaporization and solidification points of sulfur trioxide.

Abstract: The invention is a method for working-up shale while recovering metals therefrom and the sulphur content thereof. The method comprises crushing the shale and leaching and roasting the shale. The sulphur content is oxidized and converted into sulphuric acid, concentrated sulphur dioxide or sulphur. The leaching operation is effected with sulphuric acid. The leached metals are recovered in a manner known per se and the residual solution is passed to the roasting stage.

Abstract: A process for the production of hydrogen fluoride, phosphoric anhydride, calcium polyphosphates and nitric acid, is disclosed, characterized in that natural phosphate is heated by a plasma stream of working gas in the presence of water vapors to form hydrogen fluoride which is recovered as a commercial product. Then the thus defluorinated phosphate is further heated by an air plasma stream having a bulk temperature of at least 3,500.degree. K. and containing nitrogen oxides. Under such conditions, the defluorinated phosphate decomposes to form phosphoric anhydride and calcium oxide.The gas stream carrying the phosphoric anhydride, the calcium oxide and the nitrogen oxides is cooled down to yield, as commercial products, either phosphoric anhydride and nitric acid, or calcium polyphosphates containing up to 70% P.sub.2 O.sub.5 and nitric acid, or else all of the three products, depending on the cooling conditions.

Abstract: A dry alkaline earth metal metasilicate or an alkali metal metasilicate is chemically reacted with a concentrated mineral acid in the ratio of 1:3 mols to produce silicoformic hydrogen salts and an alkali hydrogen salt. The silicoformic hydrogen salt is washed with water then filtered to remove the salt and mineral acid, thereby producing silicoformic acid.

Abstract: Improvement in the oxygen oxidation of phosphorus trihalides, particularly phosphorus trichloride, to phosphorus oxyhalide, particularly oxychloride, by introducing phosphorus trihalide and gaseous oxygen into the bottom of an elongated, substantially vertical reaction zone, passing said phosphorus trihalide and oxygen upwardly through said zone while reacting such together; withdrawing a portion of the upwardly flowing reaction mixture from an intermediate point in said zone; introducing oxygen into admixture with said withdrawn admixture and cooling, agitating and reacting such; returning said admixture reaction mass to said elongated reaction zone; and recovering substantially pure phosphorus oxyhalide from the downstream end of said reaction zone.

Abstract: A process of carbo-chlorination of AlPO.sub.4 wherein AlPO.sub.4 or AlPO.sub.4 -containing material is introduced into a reactor along with chlorinating agents and a source of carbon. The reactor is heated to approximately 600.degree. to 1200.degree.C and forms aluminum chlorides, phosphorous oxides, phosphorous chlorides, phosphorous oxychlorides and carbon oxides. These reaction products are then separated into three fractions by condensation, the first fraction being P.sub.2 O.sub.5, the second fraction being AlCl.sub.3 and AlCl.sub.3 .POCl.sub.3 and the third fraction being remaining gasses, namely PCl.sub.3, PCl.sub.5, P.sub.2 O.sub.3, CO and CO.sub.2. The second fraction is reacted in a further reactor to give AlCl.sub.3 and P.sub.2 O.sub.3 which are separated by distillation. The phosphorous chlorides from the third fraction are oxidized, along with the P.sub.2 O.sub.3 of the second fraction, to form P.sub.2 O.sub.5.