Patents by Inventor Keith Stuart Liddell

Keith Stuart Liddell 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).

  • Patent number: 10988826
    Abstract: This invention relates to a hydrometallurgical process for the recovery and separation of valuable precious, base or rare elements such as platinum group metals (PGMs), gold or silver, and other valuable base and rare metals such as nickel, cobalt, copper, rare earth elements (REE), yttrium and scandium, as well as uranium, thorium, manganese, zinc, cadmium, molybdenum, titanium, tin, and other minor elements such as vanadium, germanium and gallium from a feed material comprising ores, concentrates and other materials. In particular, the process comprises quantitative removal of additional base, rare and gangue elements for increased efficiency of further treatment of the solids for valuable metals recovery and/or recycling and/or separation of valuable metals from pressure leach residue and may be integrated into one or more existing valuable element extraction processes.
    Type: Grant
    Filed: June 21, 2018
    Date of Patent: April 27, 2021
    Assignee: LIFEZONE LIMITED
    Inventors: Keith Stuart Liddell, Michael David Adams
  • Publication number: 20180371578
    Abstract: This invention relates to a hydrometallurgical process for the recovery and separation of valuable precious, base or rare elements such as platinum group metals (PGMs), gold or silver, and other valuable base and rare metals such as nickel, cobalt, copper, rare earth elements (REE), yttrium and scandium, as well as uranium, thorium, manganese, zinc, cadmium, molybdenum, titanium, tin, and other minor elements such as vanadium, germanium and gallium from a feed material comprising ores, concentrates and other materials. In particular, the process comprises quantitative removal of additional base, rare and gangue elements for increased efficiency of further treatment of the solids for valuable metals recovery and/or recycling and/or separation of valuable metals from pressure leach residue and may be integrated into one or more existing valuable element extraction processes.
    Type: Application
    Filed: June 21, 2018
    Publication date: December 27, 2018
    Inventors: Keith Stuart Liddell, Michael David ADAMS
  • Patent number: 10011889
    Abstract: This invention provides a hydrometallurgical process for extracting one or more saleable products from a sulphate or chloride pregnant leach solution (PLS), or both. The products may be any one or more of the products selected from the group consisting of: precious metals including platinum group metals (PGMs), gold and silver, base metals, and rare metal elements, and metal cathodes, powders, salts or precipitates thereof; sulphur; hydrochloric acid (HCl); calcium; and silica.
    Type: Grant
    Filed: November 24, 2015
    Date of Patent: July 3, 2018
    Assignee: LIFEZONE LIMITED
    Inventors: Keith Stuart Liddell, Lisa Anne Smith, Michael David Adams
  • Patent number: 9982320
    Abstract: This invention describes a hydrometallurgical process for the recovery and separation of valuable elements, in particular gold and silver, from a feed material comprising a refractory, intractable or otherwise poorly responding to conventional treatment routes ores, concentrates and other materials. In particular, the process is a process integrated into one or more existing value element extraction processes.
    Type: Grant
    Filed: November 24, 2015
    Date of Patent: May 29, 2018
    Assignee: LIFEZONE LIMITED
    Inventors: Keith Stuart Liddell, Lisa Anne Smith, Michael David Adams
  • Patent number: 9540706
    Abstract: This invention relates to a hydrometallurgical process for extracting platinum group metals (PGMs), gold, silver and base metals from a flotation concentrate (10) containing sulphide minerals such as pentlandite and chalcopyrite, along with pyrite and pyrrohotite. The process includes a modified pressure oxidation step (12) to selectively separate base metals into sulphate medium (14), from the PGMs. The modified pressure oxidation step (12) partially or completely oxidizes sulphide minerals to produce a product slurry (14) containing base metal sulphates in solution and a solid residue containing PGMs along with sulphate and elemental sulphur. The solid residue is subjected to a thermal treatment (18) to remove sulphate and elemental sulphur from the solid residue, and to condition the PGMs to be soluble in chloride medium. The treated solid residue is the subjected to PGM recovery by leaching in chloride leaching medium (20) to recover the PGMs.
    Type: Grant
    Filed: July 12, 2013
    Date of Patent: January 10, 2017
    Assignee: LIFEZONE LIMITED
    Inventors: Keith Stuart Liddell, Michael David Adams
  • Publication number: 20160145715
    Abstract: This invention provides a hydrometallurgical process for extracting one or more saleable products from a sulphate or chloride pregnant leach solution (PLS), or both. The products may be any one or more of the products selected from the group consisting of: precious metals including platinum group metals (PGMs), gold and silver, base metals, and rare metal elements, and metal cathodes, powders, salts or precipitates thereof; sulphur; hydrochloric acid (HCl); calcium; and silica.
    Type: Application
    Filed: November 24, 2015
    Publication date: May 26, 2016
    Inventors: Keith Stuart Liddell, Lisa Anne Smith, Michael David ADAMS
  • Publication number: 20160145714
    Abstract: This invention describes a hydrometallurgical process for the recovery and separation of valuable elements, in particular gold and silver, from a feed material comprising a refractory, intractable or otherwise poorly responding to conventional treatment routes ores, concentrates and other materials. In particular, the process is a process integrated into one or more existing value element extraction processes.
    Type: Application
    Filed: November 24, 2015
    Publication date: May 26, 2016
    Inventors: Keith Stuart Liddell, Lisa Anne Smith, Michael David ADAMS
  • Publication number: 20150344990
    Abstract: This invention relates to a hydrometallurgical process for extracting platinum group metals (PGMs), gold, silver and base metals from a flotation concentrate (10) containing sulphide minerals such as pentlandite and chalcopyrite, along with pyrite and pyrrhotite. The process includes a modified pressure oxidation step (12) to selectively separate base metals into sulphate medium (14), from the PGMs. The modified pressure oxidation step (12) partially or completely oxidizes sulphide minerals to produce a N product slurry (14) containing base metal sulphates in solution and a solid residue containing PGMs along with sulphate and elemental sulphur. The solid residue is subjected to a thermal treatment (18) to remove sulphate and elemental sulphur from the solid residue, and to condition the PGMs to be soluble in chloride medium. The treated solid residue is the subjected to PGM recovery by leaching in chloride leaching medium (20) to recover the PGMs.
    Type: Application
    Filed: July 12, 2013
    Publication date: December 3, 2015
    Applicant: IFEZONE LIMITED
    Inventors: Keith Stuart Liddell, Michael David Adams
  • Patent number: 6579504
    Abstract: A hydrometallurgical treatment process for extracting platinum group metals from a flotation concentrate in which the invention revolves around obviating the matte smelting and granulating process. Instead the concentrate is submitted to pressure leaching, oxidative or reductive roasting and final recovery by means of ion exchange adsorption. Roasting is applied in order to convert the platinum group metals to a form that dissolves in chlorine/HCL and a chlorine/HCL leach that renders the platinum group metals in solution.
    Type: Grant
    Filed: January 12, 2001
    Date of Patent: June 17, 2003
    Inventor: Keith Stuart Liddell