Elemental Phosphorus Patents (Class 423/322)
  • Patent number: 5670126
    Abstract: A process for purifying elemental phosphorus, by dosing a multi-phase elemental phosphorus system, having an aqueous phase and an immiscible, elemental phosphorus phase containing antimony, with a conditioning agent selected from the group consisting of iron (II) salt or iron (III) salt with free iodine; iron (II) iodide; free iodine; iron (II) sulfate; or iron (III) sulfate in an amount effective to lower the amount of antimony in the phosphorus; agitating the resultant mixture at a temperature above the melting point of phosphorus, but below the boiling point of water, and then separating the aqueous phase from the phosphorus phase to recover a phosphorus lower in antimony content.
    Type: Grant
    Filed: February 5, 1996
    Date of Patent: September 23, 1997
    Assignee: FMC Corporation
    Inventor: Louis T. Gunkel
  • Patent number: 5588969
    Abstract: In accordance with the invention, phosphorous vapor is provided by in situ conversion of red phosphorous to white phosphorous and permitting the flow of vapor from said white phosphorous. The conversion is effected in a low pressure cell having a high temperature region for evaporating red phosphorous and a low temperature region for condensing the resulting vapor into white phosphorous. At room temperature equilibrium, the vapor pressure is dominated by the white phosphorous.
    Type: Grant
    Filed: March 29, 1995
    Date of Patent: December 31, 1996
    Assignee: Lucent Technologies Inc.
    Inventors: James N. Baillargeon, Alfred Y. Cho
  • Patent number: 5549878
    Abstract: Phossy water is a toxic liquid waste that is generated when elemental phosphorus is manufactured, stored, or processed into phosphorus-containing products. Elemental phosphorus may be prsent as a solution, as colloidal particles, and as settleable particles.The primary objects of the invention are as follows:1. To provide a process for the disposal of phossy water stored at the TVA National Fertilizer and Environmental Research Center.2. To provide a process for the recovery of phossy water that will be generated when hazardous wastes stored at the TVA National Fertilizer and Environmental Research Center are recycled.Phossy water can be disposed of by using it to quench and granulate molten slag at electric furnaces used to manufacture elemental phosphorus. The elemental phosphorus content of the phossy water is limited to about 2 parts per million.Phossy water that will be generated during recycling of hazardous wastes can be recovered by using it in the process to produce fluid fertilizers.
    Type: Grant
    Filed: May 24, 1995
    Date of Patent: August 27, 1996
    Inventor: James C. Barber
  • Patent number: 5543444
    Abstract: Disclosed is a red phosphorus flame retardant comprising a fine red phosphorus powder subjected to a surface modification treatment, said fine red phosphorus powder consisting of spherical red phosphorus particles and/or agglomerates thereof directly obtained by the thermal conversion of white phosphorus in the presence of a dispersant and has an average particle size of 10 .mu.m or smaller and of which at least 80% by weight is accounted for by particles having particle sizes of 20 .mu.m or smaller, said flame retardant having an average particle size of 15 .mu.m or smaller, with the particles having particle sizes of 35 .mu.m or smaller accounting for at least 80% by weight of the flame retardant; and a nonflammable resinous composition composed of a synthetic resin and the red phosphorus flame retardant.
    Type: Grant
    Filed: August 9, 1994
    Date of Patent: August 6, 1996
    Assignee: Rinkagaku Kogyo Co., Ltd.
    Inventors: Tsuyoshi Kobayashi, Ichiro Sakon, Shigeo Nakashima, Sachiko Numa, Yoshikazu Inao
  • Patent number: 5538702
    Abstract: A method for the treatment of a stream of exhaust gases including phosphine in which the stream is heated to a sufficiently high temperature to decompose the phosphine to phosphorus vapor and the stream is then passed into a reactor containing calcium oxide heated to above about 100.degree. C. An oxygen containing stream is also passed into the reactor.
    Type: Grant
    Filed: February 8, 1994
    Date of Patent: July 23, 1996
    Assignee: The BOC Group plc
    Inventors: James R. Smith, Peter L. Timms
  • Patent number: 5514352
    Abstract: Apparatus and process for high speed air dispersion (HSAD) and oxidation of elemental phosphorus in aqueous medium. The HSAD apparatus is an element used in a process designed for treating the highly toxic and hazardous phosphorus sludge wastes with oxygen-containing gas microbubbles at high shear rates in which the elemental phosphorus is quantitatively converted to soluble oxyphosphorus compounds which can be recovered after neutralization as fertilizer by products or disposed of as inert nonhazardous landfill material.
    Type: Grant
    Filed: July 1, 1994
    Date of Patent: May 7, 1996
    Inventors: John Hanna, Joon-Oh Jung
  • Patent number: 5310530
    Abstract: A method for purifying phosphorus to insure a low sulfur content involves intensively mixing phosphorus and concentrated sulfuric acid to form an emulsion, breaking the emulsion by contact with water or dilute sulfuric acid, and then immediately separating the phosphorus and diluted sulfuric acid. The separated phosphorus is then stored in water until further processing is desired and is characterized by a sulfur content as low as about 50 ppm.
    Type: Grant
    Filed: September 7, 1993
    Date of Patent: May 10, 1994
    Assignee: Chemie AG Bitterfeld-Wolfen
    Inventors: Arndt Zschalich, Rudolf Schumann
  • Patent number: 5296212
    Abstract: A method for purifying white phosphorus contaminated with sulfur bound thereto involves contacting contaminated white phosphorus with water, steam, aqueous solutions, or vaporized aqueous solutions, preferably alkaline, to remove bound sulfur from the phosphorus. The purified phosphorus is characterized by a sulfur content as low as 50 ppm.
    Type: Grant
    Filed: April 21, 1992
    Date of Patent: March 22, 1994
    Assignee: Chemie AG Bitterfeld-Wolfen
    Inventors: Arndt Zschalich, Rudolf Schumann
  • Patent number: 5292494
    Abstract: A process for the production of a red phosphorus powder, which comprises heating a yellow phosphorus at the boiling point therof in the presence of a dispersant selected from the group of a surfactant, a sparingly in water, finely powdered inorganic compound, an inorganic ammonium salt or an organic compound containing an amino group, thereby to partly convert the yellow phosphorus to red phosphorus, removing most of the unconverted yellow phosphorus by distillation at the boiling point of yellow phosphorus, and further removing the slight amount of the still remaining yellow phosphorus by heating a temperature not lower than the boiling point of yellow phosphorus to obtain a red phosphorus fine powder which is less apt to undergo a disproportionation reaction.
    Type: Grant
    Filed: February 18, 1993
    Date of Patent: March 8, 1994
    Assignee: Rinkagaku Kogyo Company, Ltd.
    Inventors: Yoshikazu Inao, Yasuo Nojiri, Katsutoshi Shibata
  • Patent number: 5283042
    Abstract: Impure white phosphorus values are purified to such extent as to be useful, e.g., for the preparation of P.sub.4 S.sub.10 therefrom, by (a) reacting liquid, impure white phosphorus with an aqueous suspension of a purifying amount of active charcoal to provide a mixture of purification, (b) separating such mixture of purification into a phosphorus-containing phase and an aqueous phase, (c) separating this phosphorus-containing phase, e.g., by means of a silica filter, into purified liquid white phosphorus and spent active charcoal, and (d) recovering the white phosphorus thus purified.
    Type: Grant
    Filed: December 23, 1991
    Date of Patent: February 1, 1994
    Assignee: Atochem
    Inventors: Jean-Claude Legrand, Philippe Bourdauducq, Thierry Bulinge
  • Patent number: 5270370
    Abstract: Evolution of phosphine from red phosphorus is reduced by means of acyclic, aliphatic compounds having at least one carbon-to-carbon double bond, in the alpha-position relative to an electron-withdrawing group. A preferred example of such a compound is trans-cinnamaldehyde.
    Type: Grant
    Filed: September 21, 1992
    Date of Patent: December 14, 1993
    Assignee: Albright & Wilson Limited
    Inventors: Colin A. Chilles, Tom Dutton, Mohsen Zakikihani, Simon J. Oakley
  • Patent number: 5122359
    Abstract: A process for reprocessing sulfuric acid obtained in the purification of yellow phosphorous, which comprises mixing the contaminated sulfuric acid with hydrogen peroxide and reacting this mixture in a vessel containing hot concentrated sulfuric acid at 110.degree. to 210.degree. C. in the presence of FeSO.sub.4, MnSO.sub.4 or NiSO.sub.4 as a catalyst is described.
    Type: Grant
    Filed: July 25, 1990
    Date of Patent: June 16, 1992
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Werner Pieper, Walter Biermann
  • Patent number: 5093199
    Abstract: In a stabilized, pulverulent red phosphorus comprising phosphorus particles having a maximum particle size of 2 mm whose surface is covered with a thin layer of an oxidation stabilizer, the oxidation stabilizer is composed of tin oxide hydrate.
    Type: Grant
    Filed: December 29, 1989
    Date of Patent: March 3, 1992
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Horst Staendeke, Ursus Thummler
  • Patent number: 5075088
    Abstract: Amorphous red phosphorus useful for matches, or as flame retardant is made by forming a slurry of 10-45% red phosphorus in molten white phosphorus, reducing the content of yellow phosphorus to less than 20% of the red phosphorus by separation at less than 280.degree. C., and then heating the product at above 295.degree. C. to convert, and preferably also evaporate, the white phosphorus.
    Type: Grant
    Filed: November 19, 1990
    Date of Patent: December 24, 1991
    Assignee: Albright & Wilson Limited
    Inventors: Edward J. Lowe, William S. Holmes
  • Patent number: 5041490
    Abstract: Red phosphorus flame retardants for synthetic resin are produced by a method comprising the steps of heating yellow phosphorus at temperatures of 250.degree. to 600.degree. C. to effect a partial conversion of yellow phosphorus to red phosphorus; removing unconverted yellow phosphorus; and coating particles of the resulting red phosphorus with at least one of thermosetting resin and metal hydroxide. The thus obtained red phosphorus flame retardants are very stable because of significantly improved heat resistance, water resistance and weatherability and thus can provide nonflammable resinous compositions which can be used for long period of time. The nonflammable composition consists essentially of 100 parts by weight of polyolefine resin, 20 to 200 parts by weight of hydrated inorganic filler and 0.1 to 30 parts by weight of the coated red phosphorus flame retardant.
    Type: Grant
    Filed: November 15, 1989
    Date of Patent: August 20, 1991
    Assignee: Rinkagaku Kogyo Co., Ltd.
    Inventors: Ichiro Sakon, Masao Sekiguchi, Atsushi Kanayama
  • Patent number: 5026757
    Abstract: A flame retardant comprising of spherical red phosphorus free of pulverized face which is directly produced in the form of fine powder by conversion of yellow phosphorus, without pulverizing process. The red phosphorus characterized by its surface state and shape entirely different from any prior pulverized red phosphorus has not only a high flame retarding ability, but also a superior combination of chemical and physical properties, particularly with regard to corrosion resistance, moisture resistance, mechanical strength and dielectric properties which make it highly valuable and useful as a flame retardant for various nonflammable resinous compositions used in electric articles including electronic parts, machines, automobiles and buildings. The flame retardant is desirably coated with thermosetting rein and/or hydroxide of aluminum and/or zinc, thereby greatly improved in its stability.
    Type: Grant
    Filed: July 25, 1989
    Date of Patent: June 25, 1991
    Assignee: Rinkagaku Kogyo Co., Ltd.
    Inventors: Ichiro Sakon, Masao Sekiguchi, Atsushi Kanayama
  • Patent number: 5002745
    Abstract: A process is described for the separation and recovery of phosphorus from phosphorus-dirt mixtures by adding a quaternary ammonium compound to the mixture, while it is under an aqueous cover, agitating same, and separating a lower phosphorus phase from an upper dirt phase. The mixtures are treated prior to addition of the quaternary ammonium compound, where required, by lowering their dirt to phosphorus levels sufficiently low to permit them to be destabilized.
    Type: Grant
    Filed: May 7, 1990
    Date of Patent: March 26, 1991
    Assignee: FMC Corporation
    Inventors: Alan S. Michaels, Wayne H. Lee, Theodore F. Munday
  • Patent number: 4985221
    Abstract: Phlegmatized, pulverulent red phosphorus with good free-flowing properties comprises 95 to 99.95% by weight of red phosphorus having a particle size of up to 2 mm, and 0.05 to 5% by weight of polyurethane as phlegmatization agent.This red phosphorus is prepared by introducing an aqueous polyurethane dispersion into an aqueous suspension of red phosphorus having a particle size of up to 2 mm, after a pH of from 5 to 9 has been set, in a manner such that 5 to 0.05 parts by weight of polyurethane are present per 95 to 99.95 parts by weight of red phosphorus, then stirring the mixture at a temperature of from 20 to 90.degree. C. for 0.5 to 3 hours, and finally drying the phlegmatized red phosphorus at elevated temperature after filtration.
    Type: Grant
    Filed: February 2, 1990
    Date of Patent: January 15, 1991
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Horst Staendeke, Ursus Themmler
  • Patent number: 4968499
    Abstract: A process is disclosed for converting precipitator dust obtained during production of elemental phosphorus into feedstock for the submerged-arc electric furnace. Precipitator dust is agglomerated and indurated to prepare furnace feedstock. A binder is made by reacting acidic phosphorus compounds with alkaline substances. The preferred acidic phosphorus compound is phosphoric acid, and the preferred alkaline substance is ground phosphate ore. Precipitator dust is tumbled with the binder to form agglomerates, and the agglomerates are then indurated by heating. Gases evolved during preparation of binder, agglomeration of precipitator dust, and induration of the agglomerates are scrubbed with an aqueous medium having a pH in the range of 5.5 to 6.0. Scrubber effluent is used as feedstock for the production of suspension fertilizer. The indurated agglomerates are smelted in a submerged-arc electric furnace.
    Type: Grant
    Filed: October 13, 1989
    Date of Patent: November 6, 1990
    Assignee: James C. Barber and Associates, Inc.
    Inventor: James C. Barber
  • Patent number: 4961912
    Abstract: Elemental phosphorus contained in waste ponds can be appropriately passivated to render them substantially less pyrophoric by bringing the elemental phosphorus-containing wastes into contact with an oxygen-containing gas. Substantially pure oxygen can be used to appropriately sparge the elemental phosphorus-containing wastes submerged in the waste pond. If desired, phosphorus values can be recovered in the form of an aqueous phosphate solution.
    Type: Grant
    Filed: December 31, 1987
    Date of Patent: October 9, 1990
    Assignee: Rhone-Poulenc Basic Chemicals Co.
    Inventors: Auston K. Roberts, William E. Trainer, Mark L. Blumenfeld, David L. Biederman
  • Patent number: 4902491
    Abstract: Compacted shapes of phosphatic material, suitable as a charge for a phosphorus furnace, are produced by compacting a mixture of calcined phosphate fines and phosphoric acid. The compacted shapes are conveniently produced on a roll briquetting press.
    Type: Grant
    Filed: April 18, 1989
    Date of Patent: February 20, 1990
    Assignee: FMC Corporation
    Inventors: Joseph H. Finley, Lewis L. Hammermeister, Jared S. Sproul
  • Patent number: 4889702
    Abstract: Metallic constituents, especially heavy metal constituents are removed from dust electrostatically separated from a gas mixture consisting substantially of carbon monoxide and phosphorus in vapor form obtained during the electrothermal production of yellow phosphorus. To this end, the dust is initially calcined with continuous agitation under oxidizing conditions at temperatures of 300.degree. to 800.degree. C.; next, the resulting calcined matter is mixed with carbon and the mixture is treated at temperatures of 950.degree. to 1200.degree. C. under reducing conditions with volatilization of the metallic constituents; and the volatized metallic constituents are ultimately condensed and separated.
    Type: Grant
    Filed: November 29, 1988
    Date of Patent: December 26, 1989
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Friedrich Kolkmann, Klaus Jodden
  • Patent number: 4879067
    Abstract: A flame retardant comprising of spherical red phosphorus free of pulverized face which is directly produced in the form of fine powder by conversion of yellow phosphorus, without pulverizing process. The red phosphorus characterized by its surface state and shape entirely different from any prior pulverized red phosphorus has not only a high flame retarding ability, but also a superior combination of chemical and physical properties, particularly with regard to corrosion resistance, moisture resistance, mechanical strength and dielectric properties which make it highly valuable and useful as a flame retardant for various nonflammable resinous compositions used in electric articles including electronic parts, machines, automobiles and buildings. The flame retardant is desirably coated with thermosetting resin and/or hydroxide of aluminum and/or zinc, thereby greatly improved in its stability.
    Type: Grant
    Filed: April 17, 1987
    Date of Patent: November 7, 1989
    Assignee: Rinkagaku Kogyo Co., Ltd.
    Inventors: Ichiro Sakon, Masao Sekiguchi, Atsushi Kanayama
  • Patent number: 4874593
    Abstract: A process for treating a pyrophoric P.sub.4 -containing material to convert it to a substantially non-pyrophoric P.sub.2 O.sub.5 material is described. The process comprises supplying streams of fluid P.sub.4 -containing material and an oxygen-containing gas to a reactor filled with water. The P.sub.4 -containing material and the oxygen and the oxygen-containing gas react with one another after both have entered the aqueous medium within the reactor to thereby form the desired P.sub.2 O.sub.5 material.
    Type: Grant
    Filed: July 27, 1987
    Date of Patent: October 17, 1989
    Assignee: Stauffer Chemical Company
    Inventors: Auston K. Roberts, William E. Trainer, David L. Biederman
  • Patent number: 4853288
    Abstract: Stabilized pulverulent red phosphorus consisting substantially of particles with a size of at most 2 mm, encapsulated in a thin layer of an oxidation stabilizer consisting of at least one scarcely water-soluble or water-insoluble metal hydroxide and a melamine/formaldehyde-polycondensation product.
    Type: Grant
    Filed: March 10, 1988
    Date of Patent: August 1, 1989
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Horst Staendeke, Ursus Thummler, Wilhelm Adam
  • Patent number: 4822583
    Abstract: Compacted shapes of phosphatic material, suitable as a charge for a phosphorus furnace, are produced by compacting a mixture of calcined phosphate fines and phosphoric acid. The compacted shapes are conveniently produced on a roll briquetting press.
    Type: Grant
    Filed: August 17, 1987
    Date of Patent: April 18, 1989
    Assignee: FMC Corporation
    Inventors: Joseph H. Finley, Lewis L. Hammermeister, Jared S. Sproul
  • Patent number: 4822581
    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 x=7 to 15 or very much greater than 15 (new forms of phosphorus) are useful semiconducutors 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. Top contacts forming junction devices doped with Ni and employing Ni as a back contact comprise Cu, Al, Mg, Ni, Au, Ag, and Ti. Photovoltaic, photoresistive, and photoluminescent devices are also disclosed. All semiconductor applications appear feasible.
    Type: Grant
    Filed: December 4, 1984
    Date of Patent: April 18, 1989
    Assignee: Stauffer Chemical Company
    Inventors: Christian G. Michel, Rozalie Schachter, Mark A. Kuck, John A. Baumann, Paul M. Raccah
  • Patent number: 4822584
    Abstract: A process for obtaining phosphorus from an aqueous suspension of a phosphorus slime comprising subjecting the aqueous suspension to at least one electric discharge of an energy of from 20 to 180 J as calculated per kg of the phosphorus slime in a DC electric field, or the aqueous suspension of the phosphorus slime is subjected to the effect of an AC electric field with a power of 85-250 W. The process is conducted at a temperature not below the melting point of phosphorus.
    Type: Grant
    Filed: February 3, 1988
    Date of Patent: April 18, 1989
    Assignee: Institute Organitcheskogo Sinteza I Uglekhimii An Kaz SSR
    Inventors: Murat Z. Zhurinov, Kappas Kusaiynov, Tleubai M. Alzhanov, Zhanaly S. Bekturganov, Abduali Baeshov, Asyk-At Z. Zhagufarov, Kanat S. Ibishev, Mukan D. Atabaev, Klim A. Kim
  • Patent number: 4806326
    Abstract: Nodule fines, formed by abrasion of an electric furnace feed material of phosphate shale nodules, are utilized by mixing a recycle stream of the nodule fines with fresh phosphate in the presence of phosphoric acid prior to forming the shale into nodules. The phosphoric acid prevents loss in mechanical strength of the nodule caused by admixture with the nodule fines.
    Type: Grant
    Filed: August 17, 1987
    Date of Patent: February 21, 1989
    Assignee: FMC Corporation
    Inventor: Joseph H. Finley
  • Patent number: 4806325
    Abstract: Ferrophos is treated in a plasma furnace by maintaining an electric arc between a cathode and at least one point on the surface of the ferrophos which serves as the anode in the presence of an inert plasma gas, maintaining the average temperature of the ferrophos at about 2,000.degree. C. to about 2,700.degree. C., evolving gaseous phosphorus from the ferrophos until it contains less than about 7% by weight phosphorus, removing a purified phosphorus gas as one product and a metal concentrate having a reduced phosphorus content as a coproduct.
    Type: Grant
    Filed: July 14, 1988
    Date of Patent: February 21, 1989
    Assignee: FMC Corporation
    Inventors: Theodore F. Munday, Richard A. Mohr
  • Patent number: 4777029
    Abstract: A method of extracting phosphorus from slime resides in treating the slime with a surfactant and/or a polyamphoteric electrolyte upon heating.
    Type: Grant
    Filed: December 8, 1987
    Date of Patent: October 11, 1988
    Assignee: Kazakhsky Khimiko- Tekhnologichesky Institut
    Inventors: Erken S. Bugenov, Mukan D. Atabaev, Evsei A. Selitsky, Klim A. Kim, Valery V. Klestov, Alfia K. Gaifullina, Isak K. Sataev, Vladimir F. Shulga, Erkebulan S. Murzagaliev, Jury V. Shkarupa, Manat R. Barlybaev
  • Patent number: 4761271
    Abstract: Destabilized elemental phosphorus, for example resulting from fire involvement due to exposure with air, can be treated by placing the destabilized elemental phosphorus in the presence of a weakly basic aqueous solution of an alkali metal hypochlorite as a blanketing agent. Sodium hypochlorite is preferred.
    Type: Grant
    Filed: April 24, 1987
    Date of Patent: August 2, 1988
    Assignee: Stauffer Chemical Company
    Inventors: Arthur D. F. Toy, Fred Jaffe
  • Patent number: 4746500
    Abstract: A fore line trap is located before the forepump in a vacuum system. The trap utilizes a cracker, which may be a heated filament or a plasma, and cold walls. The cracker cracks pnictide gas species such as P.sub.4 into other species such as P.sub.2 which have a higher sticking co-efficient. The pnictides are deposited on the cold walls. The cold walls preferably comprise a sleeve which may be removed from the trap and replaced by a clean one.
    Type: Grant
    Filed: July 16, 1986
    Date of Patent: May 24, 1988
    Assignee: Stauffer Chemical Company
    Inventors: Robert W. Parry, John A. Baumann, Rozalie Schachter
  • Patent number: 4746499
    Abstract: A method of decontaminating a location containing pyrophoric P.sub.4 -contamination is described. It comprises bringing to the location a portable vehicle which comprises at least one of the necessary items needed to accomplish the contacting of the P.sub.4 -contaminated material, while it is under a protective blanket of a nonflammable fluid, with an oxygen-containing gas, such as air, pure oxygen, or mixtures thereof. The portable vehicle may contain, for example, a scrubber, a source of oxygen, a pump, means to convey the oxygen-containing gas to the P.sub.4 -contaminated material, and means to convey any effluent resulting from the treatment to suitable recovery or treatment apparatus.
    Type: Grant
    Filed: July 27, 1987
    Date of Patent: May 24, 1988
    Assignee: Stauffer Chemical Company
    Inventors: Auston K. Roberts, William E. Trainer, David L. Biederman
  • Patent number: 4744971
    Abstract: In the electric arc furnace production of elemental phosphorus, cold phossy water is segregated from hot phossy water. The cold phossy water is discharged to a lined pond wherein solids settle to form a clarified cold water which is recycled for cooling and washing purposes. The hot phossy water is passed through a lamellar settler wherein phosphorus and solids are separated as a sludge to form a clarified hot water. The clarified hot water, without requiring additional heat, is recycled for process use. Phosphorus is recovered from the sludge to reduce to a minimum the amount of phosphorus discharged with dirt from the hot phossy water to the pond.
    Type: Grant
    Filed: November 14, 1986
    Date of Patent: May 17, 1988
    Assignee: FMC Corporation
    Inventors: Gordon H. Scherbel, David A. Crea, Jerry A. Keely, Ronald L. Andersen, Byron L. Nichols
  • Patent number: 4717558
    Abstract: A process is described for recovering phosphorus from pond sludge found in ponds located near phosphorus plants. An aqueous solution of the sludge, which has a phosphorus concentration in the range of 5% to 70% by weight, is heated at a temperature in the range of 165.degree. F. to 212.degree. F., preferably for about 1/2 hour to about 6 hours, washed with water at an elevated temperature, and then reheated. A phosphorus layer having an enhanced concentration of recoverable elemental phosphorus is formed as a result of this process.
    Type: Grant
    Filed: October 29, 1986
    Date of Patent: January 5, 1988
    Assignee: Occidental Chemical Corporation
    Inventors: Steven M. Beck, Edward H. Cook, Jr.
  • Patent number: 4698215
    Abstract: Stabilized powder of red phosphorus, for use as flame-retardant agent, in particular for compositions on the basis of polymers, constituted by particles of red phosphorus enveloped by a thin capsule constituted by a first layer of Al(OH).sub.3 adhering on to the surface of red phosphorus individual particles, and by a second layer, superimposed onto said first layer, constituted by a crosslinked polyconsensation resin formed by urea-melamine-phenol-formaldehyde.
    Type: Grant
    Filed: December 27, 1985
    Date of Patent: October 6, 1987
    Assignee: Saffa S.p.A.
    Inventors: Giancarlo Albanesi, Gianfranco Rinaldi
  • Patent number: 4695447
    Abstract: Hazardous waste containing inorganic compounds which contain heavy metals or particular hazardous anionic groups or which are hazardous halides or non-metal oxides or sulfides is contacted with molten aluminum to provide reduction to lower less hazardous oxidation state.
    Type: Grant
    Filed: December 17, 1985
    Date of Patent: September 22, 1987
    Assignee: Detox International Corporation
    Inventor: Clifford G. Shultz
  • Patent number: 4689121
    Abstract: A process of recovering elemental phosphorus from sludge is disclosed wherein the sludge is flash evaporated utilizing a heat transfer means and then separated from the solid impurities contained therein.
    Type: Grant
    Filed: June 28, 1982
    Date of Patent: August 25, 1987
    Assignee: Stauffer Chemical Company
    Inventor: George J. Morgan
  • Patent number: 4686094
    Abstract: Pyrophoric elemental phosphorus-containing material, e.g., solid waste containing high levels of elemental phosphorus (P.sub.4), is treated by contact with an oxygen-containing gas, such as air, to reduce the amount of elemental phosphorus contained therein while it is otherwise protected from contact with oxygen in the air by being blanketed by a non-flammable fluid (e.g., while under an aqueous protective layer). This renders the material less pyrophoric and also enables the recovery of phosphorus values therefrom, e.g., in the form of a weak phosphoric acid solution. This treatment, for example, mobilizes highly pyrophoric solid waste into a more flowable sludge or mud form while rendering it substantially more non-pyrophoric.
    Type: Grant
    Filed: August 8, 1986
    Date of Patent: August 11, 1987
    Assignee: Stauffer Chemical Company
    Inventors: Auston K. Roberts, William E. Trainer, Steve Nakamura, Leon C. Duffin, David L. Biederman
  • Patent number: 4670241
    Abstract: MP.sub.15, where M is an alkali metal is used in a generator of P.sub.4 gas. KP.sub.15 is preferred. The generator is heated to produce the P.sub.4 gas. The generator may be used in various deposition processes such as chemical vapor deposition, vacuum evaporation, and molecular beam deposition. It is particularly useful in high vacuum processes below 10.sup.-3 Torr, particularly below 10.sup.-4 Torr such as vacuum evaporation and molecular beam deposition, for example vapor phase epitaxy and molecular beam epitaxy.
    Type: Grant
    Filed: March 13, 1985
    Date of Patent: June 2, 1987
    Assignee: Stauffer Chemical Company
    Inventors: Henry S. Marek, Christian G. Michel, John A. Baumann, Mark A. Kuck
  • Patent number: 4670240
    Abstract: The invention discloses processes for preparing matched sizes of electric furnace feed materials. With the matched sizes, components of the feed mixture do not separate inside the furnace and this decreases the electric energy for smelting. Preparation of matched sizes of materials is made possible by low-temperature agglomeration followed by drying to indurate the agglomerates. Fuel requirements for induration are substantially reduced, and environmental problems associated with high-temperature agglomeration are eliminated. Phospahte ores can be agglomerated and simultaneously the ores are upgraded by increasing the P.sub.2 O.sub.5 content. Unbeneficiated phosphate ores heretofore considered unsuited for smelting can be used as phosphate sources for the production of phosphorus. A combustible gas consisting mainly of carbon monoxide and hydrogen is generated when ores are smelted. Processes are disclosed for cleaning the gas to permit it to be burned in a facility for the cogeneration of electric energy.
    Type: Grant
    Filed: April 29, 1985
    Date of Patent: June 2, 1987
    Assignee: James C. Barber and Associates, Inc.
    Inventor: James C. Barber
  • Patent number: 4666696
    Abstract: Cholinesterase inhibiting agents such as nerve gas agents and pesticide agents are destroyed by reaction with molten aluminum and the gaseous products are analyzed and recycled if they are not essentially free of such agents.
    Type: Grant
    Filed: March 29, 1985
    Date of Patent: May 19, 1987
    Assignee: Detox International Corporation
    Inventor: Clifford G. Shultz
  • Patent number: 4664896
    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.
    Type: Grant
    Filed: November 14, 1983
    Date of Patent: May 12, 1987
    Assignee: FMC Corporation
    Inventor: Richard E. Hall
  • Patent number: 4656020
    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 provide 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 produce is high grade. In 3, phosphorus furnaces are not available at the plant site and recycling the solid wastes is impractical.
    Type: Grant
    Filed: August 7, 1985
    Date of Patent: April 7, 1987
    Assignee: James C. Barber and Associates, Inc.
    Inventor: James C. Barber
  • Patent number: 4620968
    Abstract: Monoclinic phosphorus is produced in a single source vapor transport apparatus comprising a sealed evacuated ampoule containing a mixture or compound of phosphorus and an alkali metal with the phosphorus to alkali metal ratio being 11 or greater. The charge is heated to 550.degree.-560.degree. C. and the monoclinic phosphorus crystals are formed on the cooler surface at the top of the ampoule over the temperature range of 500.degree.-560.degree. C. The preferred heating temperature is in the neighborhood of 555.degree. C. and the preferred deposition temperature is in the neighborhood of 539.degree. C. Alkali metals that may be employed include sodium, potassium, rubidium and cesium. The monoclinic phosphorus crystals form in two habits. Those formed in the presence of sodium and cesium are in the form of flat square platelets up to 4 mm on a side and 2 mm thick. These platelets may be easily cleaved into thinner platelets, like mica.
    Type: Grant
    Filed: September 17, 1982
    Date of Patent: November 4, 1986
    Assignee: Stauffer Chemical Company
    Inventors: Christian G. Michel, Rozalie Schachter, Mark A. Kuck, John A. Baumann, Paul M. Raccah
  • Patent number: 4618345
    Abstract: Liquid white phosphorus is distilled from red phosphorus in vacuo at 480.degree.-490.degree. C. The vapor is transferred in a conduit maintained at 250.degree. C. and condensed into liquid white phosphorus at room temperature. The liquid white phosphorus is then filtered to eliminate any condensed red phosphorus. The clear, colorless phosphorus produced may be utilized as a source of P.sub.4 species for chemical vapor deposition, sputtering, vacuum deposition, and molecular beam deposition of phosphorus, polyphosphide, and other phosphorus compound films for semiconductor and other applications including insulation and passivation.
    Type: Grant
    Filed: February 17, 1984
    Date of Patent: October 21, 1986
    Assignee: Stauffer Chemical Company
    Inventors: Mark A. Kuck, Susan W. Gersten
  • Patent number: 4608241
    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 phosphorus 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.
    Type: Grant
    Filed: April 29, 1985
    Date of Patent: August 26, 1986
    Assignee: James C. Barber and Associates, Inc.
    Inventor: James C. Barber
  • Patent number: 4605540
    Abstract: The present invention concerns an improvement in the electric furnace process for making elemental phosphorus. The invention features the deliberate addition of an alkali to the burden or charge that is fed to the furnace. Several advantages are gained by the addition of an alkali: pollution is reduced by scavenging fluorine compounds, operating efficiencies are gained, and control over the process is simplified.
    Type: Grant
    Filed: November 1, 1985
    Date of Patent: August 12, 1986
    Inventor: John E. Stauffer
  • Patent number: 4575403
    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.
    Type: Grant
    Filed: June 1, 1984
    Date of Patent: March 11, 1986
    Assignee: FMC Corporation
    Inventors: Harvey Rosenhouse, Jeffrey C. Dore