Abstract: The disclosure relates to a process for purifying crude, concentrated wet-processed phosphoric acid. To this end, the disclosure provides:(a) for the organic solvent to be mixed with the starting product in a ratio by volume of more than 4:1 to effect in a single process step the extraction--from the crude wet-processed phosphoric acid--of a quantity of phosphoric acid necessary for 40 to 70 weight % of the P.sub.2 O.sub.5 used to go into the organic phase, and for the resulting aqueous phosphoric acid raffinate to contain at most 28-32 weight % P.sub.2 O.sub.

Abstract: The disclosure relates to a process for removing foreign components, especially zinc, from the product cycle during the production of yellow phosphorus inside and electrothermal furnace. To this end, the disclosure provides for molten ferrophosphorus and a calcium metasilicate slag and also a dust-containing gas mixture consisting essentially of carbon monoxide and phosphorus in vapor form to be taken from the furnace charged with phosphate pellets, coke and gravel. After electrostatic separation of the dust from the gas mixture, the dust is water-treated and made into a dust suspension. Crude phosphate is granulated on a granulating means using a mixture of dust suspension and binder which preferably is a clay suspension. The granulated material is calcined on a sintering device and made into phosphate pellets. A portion of the molten slag taken from the electrothermal furnace is allowed to solidify and the solidified slag is ground.

Abstract: Red amorphous phosphorus is formed by thermal conversion of yellow phosphorus by a process wherein thermal conversion is effected while simultaneously the heat of conversion is permitted to effect evaporation of yellow phosphorus. The evaporated yellow phosphorus is condensed, collected and used in a subsequent conversion batch. The red amorphous phosphorus is obtained substantially free from residual unconverted yellow phosphorus and in a physical form which allows ready further processing to particulate form.

Abstract: Processes and compositions of matter are disclosed for the production of liquid fertilizers wherein wastewater from a phosphorus smelting furnace is incorporated in liquid fertilizer processes. The wastewater replaces water evaporated and the wastewater dissolves fertilizer salts. A serious water pollution problem is avoided when wastewater is incorporated in liquid fertilizers. The invention discloses a process for making orthophosphate suspension fertilizer wherein impure phosphoric acid is neutralized in the condensing system, water from the condensing system is bled off, and a suspending clay is added to produce orthophosphate suspension fertilizer. In this process, phosphorus sludge made at phosphorus furnaces is used to produce suspension fertilizer, and wastewater from phosphate smelting furnaces is recovered. New compositions of matter are disclosed.

Abstract: High phosphorus polyphosphides, namely MP.sub.x, where M is an alkali metal (Li, Na, K, Rb, and Cs) or metals mimicking the bonding behavior of an alkali metal, and where x=7 to 15 or very much greater than 15 (new forms of phosphorus) are useful semiconductors in their crystalline, polycrystalline and amorphous forms (boules and films). MP.sub.15 appears to have the best properties and KP.sub.15 is the easier to synthesize. P may include other pnictides as well as other trivalent atomic species. Resistance lowering may be accomplished by doping with Ni, Fe, Cr, and other metals having occupied d or f outer electronic levels; or by incorporation of As and other pnictides. Rectifying Schottky junction devices doped with Ni and employing Ni as a back contact comprise Cu, Al, Mg, Ni, Au, Ag, and Ti as junction forming top contacts. Photovoltaic, photoresistive, and photoluminescent devices are also disclosed. All semiconductor applications appear feasible.

Abstract: Particulate red amorphous phosphorus is stabilized against oxidation and phosphine formation by the use of a combination of titanium dioxide or titanium phosphate and an organic resin, usually an epoxy resin, a melamine-formaldehyde resin or a urea-formaldehyde resin.

Abstract: A continuous process for reducing the arsenic content of phosphorus is described in which the impure phosphorus is continually passed through a heat exchanger and heated to vaporize a portion of the phosphorus at a temperature not above 200.degree. C., separating the vaporized phosphorus in a disengaging zone under subatmospheric pressure and introducing it into a fractionating zone under subatmospheric pressure, fractionating the phosphorus from the less volatile arsenic, condensing under subatmospheric pressure low-arsenic phosphorus rising from the fractionating zone, returning a portion of the low-arsenic phosphorus condensate as reflux to the column, removing high-arsenic liquid phosphorus as bottoms from the fractionating zone, and recovering the remaining portion of low-arsenic phosphorus condensate as product.

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: Liquid phosphorus as produced by the reduction of a phosphate ore in an electric arc furnace while of high purity contains color-causing impurities that impart to the phosphorus a black color by reflected light. Such liquid phosphorus is polished or refined to exhibit a yellow or yellow brown cast by mixing it with hot water and subjecting the mixture to intense agitation. The refined phosphorus is separated from the water phase which retains the impurities.

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: A device for metering liquid yellow phosphorus into a rotating ball mill for the production of red phosphorus therein includes a stationary outer tubular structure surrounding an inner tubular structure rotatably mounted therein. A valve having a valve rod associated with it is installed within the inner tubular structure near its end close to the ball mill. A plug provided with a central bore receiving the valve rod is installed within the inner tubular structure near its end remote from the ball mill. A bellows surrounds a portion of the valve rod inside the inner tubular structure, the bellows being tightly connected to the plug and valve rod.

Abstract: Particulate red amorphous phosphorus is stabilized against oxidative degradation to phosphorus acids and phosphine by the use of titanium dioxide or titanium phosphate.

Abstract: A process and product of waste recovery at phosphorus furnaces is disclosed wherein small sized discrete particles of carbonaceous material or beneficiated phosphate ore are mixed with a mineral acid, an alkaline fluid and water, and the reacted mixture is tumbled in a horizontal cylinder at a temperature below that at which the carbonaceous material oxidizes to form agglomerates which are then indurated to discrete particulate size as desired for a charge component; the agglomerates are fed to a phosphorus smelting furnace together with other materials needed to make elemental phosphorus, furnace gases are cooled with recirculating water, a side stream of the water is taken off, treated, and used as feedstock in fluid fertilizers. Apparatus is disclosed for agglomerating coke and phosphate and, further, for measuring the abrasion and shatter resistance of agglomerates.

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 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 method for purifying yellow phosphorus is disclosed comprising contacting the molten phosphorus with a solid phosphorus acid containing catalyst comprising an oxygen acid of phosphorus carried on an inert absorbant support. The purified phosphorus is thereafter separated from the solid catalyst and preferably is separated therefrom by filtration through the catalyst layer.

Abstract: This invention relates to fire retarded polymeric composition comprising a polymeric material, red phosphorus and a phosphine suppressant which is a copper salt.

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: The invention relates to an apparatus for making red phosphorus by subjecting molten yellow phosphorus to a thermal conversion reaction in a closed reaction zone. To this end, a hollow shaft-provided and closed ball mill is preheated to a reaction temperature within the range 280.degree. to 590.degree. C. Yellow phosphorus is continuously introduced into the ball mill through the hollow shaft in quantities per unit time which permit the reaction temperature prevailing inside the ball mill to be maintained without supply of heat from the outside. More particularly, decreasing quantities of yellow phosphorous are introduced per unit time at increasing temperature and increasing quantities of yellow phosphorus are introduced per unit time at decreasing temperature within the limits specified. Red phosphorus is allowed to cool inside the ball mill, water is poured over it and the whole is subjected to wet-grinding. An aqueous suspension of red phosphorus is finally removed from the ball mill.

Abstract: The invention relates to stabilized, pulverulent red phosphorus, consisting of phosphorus particles having a particle size of at most about 2 mm, and an oxidation stabilizer which envelops the phosphorus particles in the form of a thin layer, wherein(a) the oxidation stabilizer is a combination of aluminum hydroxide and a hardened epoxide resin system having an epoxide equivalent weight of about 170 to 500,(b) the total amount of the oxidation stabilizer is 0.1-5% by weight, based on the amount of red phosphorus, and(c) the proportion of aluminum hydroxide is about 0.01 to 3% by weight, and the proportion of epoxide resin is about 0.09 to 4.99% by weight, in each case based on the amount of the red phosphorous.

Abstract: An improved process for the wet-acid process for manufacture of phosphoric acid with recovery of valuable co-products is provided. Phosphate rock is digested in a sulfuric acid/phosphoric acid mixture. Phosphoric acid is filtered from the digested rock, the gypsum thus formed, and sludge from the phosphoric acid, are second-stage acid treated, washed, and heated in a drier-calciner at 900.degree. to 1300.degree. C. Sulfur dioxide evolved from the gypsum and the fossil fuel is used to replenish the sulfuric acid. The hot impure lime remaining is fused in an electric furnace to form valuable calcium aluminum silicate products, which are then tapped, cooled, stored, and sold. The only waste products from the process are common, sulfur dioxide free combustion gases from the high sulfur content fossil fuel. Nearly 100% recovery of all phosphorus and fluorine values is claimed.

Abstract: The invention is a process for purifying elemental yellow phosphorus by contacting the yellow phosphorus with an aliphatic alcohol-tetraalkyl ammonium halide solution which effectively removes impurities and produces a colorless product.

Abstract: The invention relates to a process for making red phosphorus by subjecting molten yellow phosphorus to a thermal conversion reaction in a closed reaction zone. To this end, a hollow shaft-provided and closed ball mill is preheated to a reaction temperature within the range 280.degree. to 590.degree. C. Yellow phosphorus is continuously introduced into the ball mill through the hollow shaft in quantities per unit time which permit the reaction temperature prevailing inside the ball mill to be maintained without supply of heat from the outside. More particularly, decreasing quantities of yellow phosphorus are introduced per unit time at increasing temperature and increasing quantities of yellow phosphorus are introduced per unit time at decreasing temperature within the limits specified. Red phosphorus is allowed to cool inside the ball mill, water is poured over it and the whole is subjected to wet-grinding. An aqueous suspension of red phosphorus is finally removed from the ball mill.

Abstract: The invention provides stabilized pulverulent red phosphorus comprising a homogeneous blend of red phosphorus particles with a size of at most about 2 mm, aluminum hydroxide and a further metal hydroxide as oxidation stabilizers, wherein the metal hydroxide is lead hydroxide. The homogeneous blend contains aluminum hydroxide and lead hydroxide in a total proportion of about 0.1 to 6 weight %, based on the quantity of red phosphorus, the aluminum hydroxide and lead hydroxide, calculated as Al.sub.2 O.sub.3 to PbO, being used in a quantitative ratio of about 0.5 to 2.0.

Abstract: The method comprises processing slime and off-gases resulting from the production of phosphorus with an aqueous solution of copper sulphate having a concentration of from 15 to 50% at a temperature within the range of from 20.degree. to 80.degree. C. As a result, two products are obtained, i.e. a liquid product and a solid one.The solid product containing mainly copper phosphide as well as fluorides and chlorides of alkali metals and silicon, and silicates of calcium and aluminum, is used as a modifying and refining agent for hypereutectic silumines and for the manufacture of a copper-phosphorus alloy.The liquid product containing phosphoric acid, sulphuric acid and copper sulphate is used as starting product for the preparation of a copper-containing fertilizer.The method according to the present invention makes it possible to modify the production of phosphorus so as to eliminate the formation of secondary wastes and improve the environmental control.

Abstract: Particulate red phosphorus is obtained by thermal conversion of white phosphorus in an essentially dry process in which liquid white phosphorus is injected onto a bed of red phosphorus particles preheated to a temperature above the thermal conversion temperature while controlling the heat generation.

Abstract: Off gases from electric furnace production of phosphorus, consisting essentially of carbon monoxide and phosphine, are heated to 700.degree.-800.degree. C. to decompose the phosphine to red phosphorus and hydrogen; the red phosphorus is separated from the gas--most desirably by passing the gas through aqueous hydrogen peroxide which oxidizes the phosphorus to phosphoric acid,--to obtain a clean gas which can be used as a fuel.

Abstract: Installation for the production of yellow phosphorus comprises an electrothermal furnace and an apparatus for preliminary melting of phosphate-quartzite charge. This apparatus communicates with the bath of the electrothermal furnace via a melt collector and a liquid seal. Said apparatus and the melt collector comprise a pipe unit forming an evaporator circuit. Electrodes are arranged in the electrothermal furnace in such a manner that the first electrode in the direction of flow of melt from the collector to the furnace is located opposite to the liquid seal. A process for the production of yellow phosphorus effected in the above-described installation comprises melting phosphates with grading less than 10 mm and quartzite comminuted into flour in the apparatus for preliminary melting, concurrent defluorination of the melt by treating it in a thin layer with overheated steam obtained from moisture contained in fuel combustion products and feeding the defluorinated melt into the electrothermal furnace.

Abstract: Red phosphorus, usually in amorphous form, is obtained by heating liquid white phosphorus at a temperature of between 250.degree. and 590.degree. C. while the phosphorus is subjected to a pressure greater than the theoretical vapor pressure of white phosphorus at the heating temperature. The application of such pressure minimizes phosphorus vapor formation during the conversion to red phosphorus. The process may be carried out by feeding liquid white phosphorus into an extrusion head heated to the reaction temperature while subjecting the white phosphorus to the appropriate pressure in the extrusion head, the red phosphorus being extruded from the extrusion head into an inert atmosphere. Alternatively, molten white phosphorus in droplet form may be pumped into an inert immiscible heat exchange fluid, such as, lead, at the reaction temperature, the appropriate pressure applied in the fluid and particulate red phosphorus separated from the fluid.

Abstract: Production of stabilized pulverulent red phosphorus. The phosphorus so stabilized comprises a homogeneous blend of red phosphorus particles with a size of at most about 2 mm and a metal compound of the second or third group of the Periodic System as an oxidation stabilizer, wherein the metal compound is the aluminum, calcium or zinc salt of a phosphinic acid of the general formula ##STR1## in which R.sub.1 and R.sub.2 each stand for an alkyl, cycloalkyl, aryl or aralkyl group having 1 to 20 carbon atoms, the metal compound being present in the homogeneous blend in a proportion of about 0.5 to 5 weight %.

Abstract: The invention provides stabilized pulverulent red phosphorus. It comprises a homogeneous blend of red phosphorus particles with a size of at most about 2 mm and a metal compound of the second or third group of the Periodic System as an oxidation stabilizer, wherein the metal compound is the neutral aluminum, magnesium, calcium or zinc salt of orthophosphoric acid, the metal compound being present in the homogeneous blend in a proportion of about 0.5 to 5 weight %.

Abstract: The invention provides stabilized pulverulent red phosphorus. It comprises a homogeneous blend of red phosphorus particles with a size of at most about 2 mm and a metal compound of the second or third group of the Periodic System as an oxidation stabilizer, wherein the metal compound is the aluminum, magnesium, calcium or zinc salt of an alkyl-, cycloalkyl-, aryl- or aralkylphosphonic acid having 1 to 20 carbon atoms, the metal compound being present in the homogeneous blend in a proportion of about 0.5 to 5 weight %.

Abstract: The invention provides stabilized pulverulent red phosphorus. It comprises a homogeneous blend of red phosphorus particles with a size of at most about 2 mm and a metal compound of the second or third group of the Periodic System as an oxidation stabilizer, wherein the metal compound is the aluminum, magnesium, calcium or zinc salt of an acid orthophosphoric acid ester of a long chain aliphatic alcohol, which may be ethoxylated, or phenol, the metal compound being present in the homogeneous blend in a proportion of about 0.25 to 5 weight %.

Abstract: Phosphorus is recovered from phosphorus mud by introducing a skip of phosphorus mud into a furnace, closing the furnace and contacting the skip inside the furnace with a pool of molten lead. Phosphorus vapour is distilled from the mud and recovered.

Abstract: Ferrophosphorus is utilized. To this end, a melt of ferrophosphorus is reacted with a melt of calcium silicide so as to obtain ferrosilicon and calcium phosphide.

Abstract: The invention provides a process for the production of yellow phosphorus. One embodiment involves (a) comminuting a natural phosphate having a grading not exceeding 10 mm. and quartzite into a finely-divided state and mixing together said comminuted phosphates and quartzite to obtain a two-component phosphate-quartzite charge; (b) melting said two-component phosphate-quartzite charge; (c) treating the resulting phosphate-quartzite melt, while in a thin layer, with overheated steam to form fluorine compounds; (d) removing the fluorine compounds; (e) feeding to the surface of the remaining defluorinated melt a three-component charge consisting essentially of a mixture of heat-treated lump phosphate and quartzite having a grading of about from 10-50 mm., together with a reducing agent having a grading of about from 5-25 mm.

Abstract: A process for the production of phosphorus from low-grade phosphate rock containing at least 5% by weight of each of iron and aluminum (calculated as their oxides) by heating a mixture of the rock, calcium oxide and a carbonaceous reductant in a reaction chamber at a temperature of at least 1400.degree. C to produce molten reaction products containing ferrophosphorus and a calcium aluminate slag which is liquid at the reaction temperature, and gaseous reaction products containing elemental phosphorus. The gaseous reaction products are withdrawn from the reaction chamber and elemental phosphorus is recovered therefrom. The ferrophosphorus is separated from the liquid calcium aluminate slag and subjected to an oxidizing treatment in the presence of a calcium-containing material to produce metallic iron and calcium phosphate. Calcium phosphate this produced is recycled to the reaction chamber.

Abstract: There is provided a method for preparing phosphorus compounds wherein phosphorus vapor containing P.sub.2 molecules is condensed at a temperature below the solidification point of red phosphorus and the resulting solid is then reacted with a phosphorus-reactive material. When the phosphorus-reactive material is water at an elevated temperature, phosphine is produced.

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: An agitated reactor is described for use in the continuous conversion of liquid white phosphorus to red phosphorus. Critical relations of the reactor vessel shape and measurements and the agitator measurements are described for preventing build-up of red phosphorus solids in the reactor as the continuous conversion proceeds.

Abstract: Desensitized free-flowing red phosphorus. The phosphorus is comprised of a homogeneous blend consisting of between about 80 and 98 weight% of red phosphorus having a particle size of up to about 2 mm, and of between about 2 and 20 weight% of an organic or organo-silicon compound desensitizer. The desensitizer is liquid, inactive with respect to red phosphorus and has a minor vapor pressure at room temperature at atmospheric pressure.