Patents by Inventor Wilhelmina Du Plessis

Wilhelmina Du Plessis has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Treatment of chemical feedstocks
    Patent number: 9468975
    Abstract: A process for treating a zirconium containing feedstock includes fluorinating a feedstock comprising dissociated zircon (‘DZ’) to obtain a zirconium fluorine compound and a silicon fluorine compound. The zirconium fluorine compound is separated from the silicon fluorine compound is provided. Optionally, the zirconium fluorine compound is reacted with a non-fluorine halogen, an alkali metal non-fluorine halide or an alkaline-earth metal non-fluorine halide, thereby to obtain a zirconium non-fluorine halide. The zirconium fluorine compound or, when present, the zirconium non-fluorine halide is subjected to plasma reduction, in a plasma reduction stage, in the presence of a reductant, to obtain metallic zirconium.
    Type: Grant
    Filed: October 11, 2012
    Date of Patent: October 18, 2016
    Assignee: The South African Nuclear Energy Corporation Limited
    Inventors: Johannes Theodorus Nel, Willem Liebenberg Retief, Johan Louis Havenga, Wilhelmina Du Plessis, Johannes Petrus Le Roux
  • Treatment of minerals
    Patent number: 9416431
    Abstract: A process for treating a feedstock is provided. The feedstock comprises a mineral and/or a metal oxide/silicate derived from or associated with a mineral. The process comprises treating the feedstock by reacting, in a reaction step, the mineral and/or the metal oxide/silicate derived from or associated with a mineral, with an ammonium acid fluoride having the generic formula NH4F.xHF, wherein 1<x?5. An ammonium fluorometallate compound is produced as a reaction product.
    Type: Grant
    Filed: September 9, 2010
    Date of Patent: August 16, 2016
    Assignee: The South African Nuclear Energy Corporation Limited
    Inventors: Willem Liebenberg Retief, Nelius Dempers Retief, Johannes Theodorus Nel, Wilhelmina Du Plessis, Philippus Lodewyk Crouse, Johannes Petrus Le Roux
  • TREATMENT OF CHEMICAL FEEDSTOCKS
    Publication number: 20140238195
    Abstract: A process for treating a zirconium containing feedstock includes fluorinating a feedstock comprising dissociated zircon (‘DZ’) to obtain a zirconium fluorine compound and a silicon fluorine compound. The zirconium fluorine compound is separated from the silicon fluorine compound is provided. Optionally, the zirconium fluorine compound is reacted with a non-fluorine halogen, an alkali metal non-fluorine halide or an alkaline-earth metal non-fluorine halide, thereby to obtain a zirconium non-fluorine halide. The zirconium fluorine compound or, when present, the zirconium non-fluorine halide is subjected to plasma reduction, in a plasma reduction stage, in the presence of a reductant, to obtain metallic zirconium.
    Type: Application
    Filed: October 11, 2012
    Publication date: August 28, 2014
    Applicant: The South African Nuclear Energy Corporation Limited
    Inventors: Johannes Theodorus Nel, Willem Liebenberg Retief, Johan Louis Havenga, Wilhelmina Du Plessis, Johannes Petrus Le Roux
  • Treatment of zirconia-based material with ammonium bi-fluoride
    Patent number: 8778291
    Abstract: A process for treating a zirconia-based material comprises reacting, in a reaction step, the zirconia-based material with ammonium bifluoride, NH4F.HF. An ammonium fluorozirconic compound is produced.
    Type: Grant
    Filed: July 29, 2010
    Date of Patent: July 15, 2014
    Assignee: The South African Nuclear Energy Corporation Limited
    Inventors: Johannes Theodorus Nel, Wilhelmina Du Plessis, Philippus Lodewyk Crouse, Nelius Dempers Retief
  • TREATMENT OF ZIRCONIA-BASED MATERIAL WITH AMMONIUM BI-FLUORIDE
    Publication number: 20130011329
    Abstract: A process for treating a zirconia-based material comprises reacting, in a reaction step, the zirconia-based material with ammonium bifluoride, NH4F.HF. An ammonium fluorozirconic compound is produced.
    Type: Application
    Filed: July 29, 2010
    Publication date: January 10, 2013
    Inventors: Willem Liebenberg Retief, Nelius Dempers Refief, Johannes Theodorus Nel, Wilhelmina Du Plessis, Philippus Lodewyk Crouse
  • TREATMENT OF MINERALS
    Publication number: 20120328496
    Abstract: A process for treating a feedstock is provided. The feedstock comprises a mineral and/or a metal oxide/silicate derived from or associated with a mineral. The process comprises treating the feedstock by reacting, in a reaction step, the mineral and/or the metal oxide/silicate derived from or associated with a mineral, with an ammonium acid fluoride having the generic formula NH4F.xHF, wherein 1<x?5. An ammonium fluorometallate compound is produced as a reaction product.
    Type: Application
    Filed: September 9, 2010
    Publication date: December 27, 2012
    Inventors: Willem Liebenberg Retief, Nelius Dempers Retief, Johannes Theodorus Nel, Wilhelmina Du Plessis, Philippus Lodewyk Crouse, Johannes Petrus Le Roux