摘要:
The present invention discloses a reduction-oxidation furnace for thermally refining phosphorus. The reduction-oxidation furnace comprises a furnace body and a blow gun, wherein the furnace body has a slag outlet, a fume outlet, and a melt inlet for feeding melts formed by melting rock phosphate into the furnace body and wherein the blow gun has an end inserted into the furnace body. The content of impurities in fumes containing phosphorus pentaoxide is low, the phosphorus pentaoxide can be easily extracted with a high purity of the phosphorus pentaoxide and at low cost by means of the reduction-oxidation furnace for thermally refining phosphorus according to the present invention.
摘要:
In general, the present invention relates to the production of ultrapure phosphorus. In particular, the present invention relates to the method for the production of ultrapure phosphorus by zone melting in a Non-flammable environment and the equipments used in such method. The process of the present invention is clean, chemical free, fast, and energy efficient.
摘要:
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.
摘要:
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. The other habit formed in the presence of potassium and rubidium is in the form of a truncated pyramid up to 4 mm.times.3 mm.times.2 mm high. This habit is hard to cleave. The crystals are semiconductors with a band gap, indicated by photoluminescence, of about 2.1 eV at room temperature. Powder X-ray diffraction, and differential thermal analysis are consistent with that reported for Hittorf's phosphorus prepared according to the prior art. The crystals are a deep red on transmission and birefringent, rotating the plane of polarization in a polarizing microscope. They contain from 50 to 2000 parts per million of alkali metal and therefore may be utilized as a form of very pure phosphorus as well as for their semiconducting and birefringent qualities and as phosphors.
摘要:
A process for separating heavy metals from a phosphoric starting material includes, in a step (i), heating the starting material to a temperature between 700 and 1,100° C. in a first reactor and withdrawing combustion gas. In a step (ii), the heated starting material at the temperature between 700 and 1,100° C. is transferred to a second reactor, chlorides of alkaline and earth alkaline metals are added and process gas is withdrawn.
摘要:
Provided is a method for preparing high-purity elemental phosphorus capable of simultaneously reducing both arsenic and antimony from crude white phosphorus containing a great amount of arsenic and antimony as impurities. Provided is a method for preparing high-purity elemental phosphorus, the method including bringing liquid crude white phosphorus into contact with an iodic acid-containing compound selected from iodic acid and iodates in an aqueous solvent in the presence of a chelating agent, wherein the chelating agent is selected from polyvalent carboxylic acids, polyvalent carboxylates, phosphonic acid and phosphonates.
摘要:
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.
摘要:
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 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. 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.These semiconductors belong to the class of polymer forming, trivalent atomic species forming homatomic, covalent bonds having a coordination number slightly less than 3. The predominant local order appears to be all parallel pentagonal tubes in all forms, including amorphous, except for the monoclinic and twisted fiber allotropes of phosphorus.Large crystal monoclinic phosphorus (a birefringent material) in two habits, a twisted fiber phosphorus allotrope and a star shaped fibrous high phosphorus material are also disclosed.Single and multiple source vapor transport, condensed phase, melt quench, flash evaporation, chemical vapor deposition, and molecular flow deposition may be employed in synthesizing these materials. Vapor transport may be employed to purify phosphorus.
摘要:
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 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. 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.These semiconductors belong to the class of polymer forming, trivalent atomic species forming homatomic, covalent bonds having a coordination number slightly less than 3. The predominant local order appears to be all parallel pentagonal tubes in all forms, including amorphous, except for the monoclinic and twisted fiber allotropes of phosphorus.Large crystal monoclinic phosphorus (a birefringent material) in two habits, a twisted fiber phosphorus allotrope and a star shaped fibrous high phosphorus material are also disclosed.Single and multiple source vapor transport, condensed phase, melt quench, flash evaporation, chemical vapor deposition, and molecular flow deposition may be employed in synthesizing these materials. Vapor transport may be employed to purify phosphorus.The materials may be employed as protective coatings, optical coatings, fire retardants, fillers and reinforcing fillers for plastics and glasses, antireflection coatings for infrared optics, infrared transmitting windows, and optical rotators.