Melting Out Patents (Class 23/308R)
  • Patent number: 5976478
    Abstract: Internal porosity is created in dense SiO.sub.2 particles by heating a mixture of the particles with B.sub.2 O.sub.3 at a temperature above about 450.degree. C. Resulting SiO.sub.2 particles have altered morphology, internal porosity, and small to negative volume changes when heated.
    Type: Grant
    Filed: December 21, 1998
    Date of Patent: November 2, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Donald Keith Swanson, Salvatore Anthony Bruno
  • Patent number: 5861134
    Abstract: Internal porosity is created in dense SiO.sub.2 particles by heating a mixture of the particles with B.sub.2 O.sub.3 above the melting point of both mixture components. Resulting SiO.sub.2 particles have altered morphology, internal porosity, and a negative thermal expansion coefficient when heated.
    Type: Grant
    Filed: June 9, 1997
    Date of Patent: January 19, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: Donald Keith Swanson
  • Patent number: 5447542
    Abstract: In the process for separating and purifying substances by crystallization from the melt under pressure, the melt is subjected to pressure under an inert gas atmosphere and then cooled, whereupon it crystallizes. The residual melt is separated from the resulting crystals, after which the crystals are degassed by reducing the pressure and are caused to sweat, and the sweat oil is separated off.
    Type: Grant
    Filed: April 20, 1994
    Date of Patent: September 5, 1995
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Rudolf Steiner, Axel Konig, Siegbert Rittner
  • Patent number: 5447541
    Abstract: Process for separating and purifying substances by crystallization from the melt under high pressuresIn the process for separating or purifying substances by crystallization from melts or highly concentrated solutions under high pressures, gas is dissolved in the melt to be crystallized and is expelled again after the crystallization with reduction in the pressure. Still adhering or occluded impurities are thus removed.
    Type: Grant
    Filed: April 20, 1994
    Date of Patent: September 5, 1995
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Rudolf Steiner, Axel Konig, Siegbert Rittner
  • Patent number: 5338519
    Abstract: A process is provided for the separation of substances by melt crystallization. The organic mixtures which are difficult to crystallize are heated to a temperature sufficient to obtain a melt with the melt then being moved through a three-dimensional crystallization matrix having a large specific area. The melt is slowly cooled over a temperature range so as to achieve a selective crystallization from the supersaturated melt in the carrier matrix. A deposited crystal phase is thereafter melted and separated from the carrier matrix and removed by centrifugation. The carrier matrix may have a crystallization-promoting microstructure surface and may consist of an openpored foam.
    Type: Grant
    Filed: March 24, 1993
    Date of Patent: August 16, 1994
    Assignee: Sulzer Brothers Limited
    Inventors: Slobodan Jancic, Evangelos Sakellariou
  • Patent number: 5230769
    Abstract: A process is provided for the separation of substances by melt crystallization. The organic mixtures which are difficult to crystallize are heated to a temperature sufficient to obtain a melt with the melt then being moved through a three-dimensional crystallization matrix having a large specific area. The melt is slowly cooled over a temperature range so as to achieve a selective crystallization from the supersaturated melt in the carrier matrix. A deposited crystal phase is thereafter melted and separated from the carrier matrix and removed by centrifugation. The carrier matrix may have a crystallization-promoting microstructure surface and may consist of an openpored foam.
    Type: Grant
    Filed: December 10, 1991
    Date of Patent: July 27, 1993
    Assignee: Sulzer Brothers Limited
    Inventors: Slobodan Jancic, Evangelos Sakellariou
  • Patent number: 4584181
    Abstract: An apparatus for producing low cost, high purity solar grade Si wherein a reduction reaction, preferably the reduction of SiF.sub.4, by an alkali metal (Na preferred) is carried out inside a reaction chamber. The chamber wall and bottom surfaces are formed of graphite and configured with drainage channels so as to facilitate the continuous separation of the products of reaction (Si and NaF) and removal of the molten salt by discharging the salt through one or more ports at the bottom of the reaction chamber. Such process is especially useful where it is desirable to discharge the reaction salt products from the reactor and retain silicon within the chamber for later removal.
    Type: Grant
    Filed: December 27, 1982
    Date of Patent: April 22, 1986
    Assignee: SRI International
    Inventors: Leonard Nanis, Angel Sanjurjo
  • Patent number: 4559071
    Abstract: Converting thermally meltable materials to a liquefied state is carried out on a support surface of the unmelted material. As liquefied material is drained from the surface, additional unmelted material is fed onto the surface to maintain a substantially constant layer of the unmelted material.
    Type: Grant
    Filed: October 16, 1984
    Date of Patent: December 17, 1985
    Assignee: PPG Industries, Inc.
    Inventors: Gerald E. Kunkle, Joseph M. Matesa
  • Patent number: 4492627
    Abstract: Process for recovery of elemental phosphorus from waste ponds by dredging the waste pond to obtain an aqueous phosphorus slurry, separating particles larger than 2 mm from the slurry, treating the remaining slurry in an initial hydrocyclone and removing an overflow of solids larger than 500 micrometers, treating the underflow from the initial hydrocyclones in smaller diameter hydrocyclones, removing a second overflow enriched in slimes and diminished in phosphorus, removing a second underflow enriched in phosphorus and diminished in slimes and heating it sufficiently to melt the phosphorus therein, treating the heated second underflow in a centrifugal separator, and separating and recovering a stream of coalesced phosphorus from a heavy fraction of impurities.
    Type: Grant
    Filed: June 14, 1982
    Date of Patent: January 8, 1985
    Assignee: FMC Corporation
    Inventor: David A. Crea
  • Patent number: 4151264
    Abstract: A process of melting down and purifying silicon, which comprises melting silicon in at least half of the amount up to double of the amount of a silicate melt heated by resistance heating up to a temperature of at least 1,420.degree. C., said melt consisting of 2-30% by weight of calcium oxide, 5-35% by weight of magnesium oxide, wherein the sum of calcium oxide and magnesium oxide will be 15-38% by weight, 0.5-28% by weight of aluminum oxide and 45-70% by weight of silicon dioxide, and wherein, to the melt are added at least 0.29% by weight of elementary and/or chemically bound copper, preferably 0.50-3% by weight, calculated on the silicon amount.
    Type: Grant
    Filed: January 25, 1978
    Date of Patent: April 24, 1979
    Assignee: Wacker-Chemie GmbH
    Inventors: Anton More, Rudolf Riedle, Herbert Straussberger, Willi Streckel, Johann Muschi
  • Patent number: 3956414
    Abstract: Melting and cracking of amorphous polyolefin are carried out with a relatively small quantity of heat consumption and also with easiness in separating sludge, in converting it into oil by maintaining amorphous polyolefin at a high temperature of about 130.degree. - 300.degree.C for a relatively long time alone or together with a petroleum hydrocarbon oil to reduce the viscosity of the resultant melt to 5 - 250 CP, spraying the resultant melt upon lumps of amorphous polyolefin, separating impurities in the lumps as sludge, cracking the resultant molten mixture at a temperature of about 250.degree. - 450.degree.C and recovering oily products. For that purpose an apparatus comprising a combination of a holding tank for melt of amorphous polyolefin, a vessel for melting amorphous polyolefin equipped with a perforated plate or a wire-netting, a revolving shaft, a stirrer, etc.
    Type: Grant
    Filed: January 18, 1974
    Date of Patent: May 11, 1976
    Inventor: Katsutoshi Oshima