Patents by Inventor Thomas Tarka

Thomas Tarka 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).

  • Step-Leaching Process of Rare Earth Elements from Ash Materials Using Mild Inorganic Acids at Ambient Conditions
    Publication number: 20250115979
    Abstract: The invention provides a method for extracting REEs from ash having the steps of contacting ash with a first acid solution to generate leachate having a pH between approximately 5.0 and approximately 5.5; contacting the ash with a second acid solution to generate leachate having a pH between approximately 2.8 and approximately 3.5; and contacting the ash with a third acid solution to generate leachate having a pH between approximately ?0.6 and approximately 0.5. The invention also provides a method for leaching REEs from ash having the steps of: contacting ash with a first amount of acid sufficient to leach Ca and Al from the ash without leaching REEs; contacting the ash with a second amount of acid sufficient to leach REEs from the ash without leaching Fe and Sc; and contacting ash with a third amount of acid sufficient to leach Fe and Sc from the ash.
    Type: Application
    Filed: December 16, 2024
    Publication date: April 10, 2025
    Inventors: Mengling Stuckman, Christina L. Lopano, Thomas Tarka
  • Step-leaching process of rare earth elements from ash materials using mild inorganic acids at ambient conditions
    Patent number: 12221672
    Abstract: The invention provides a method for extracting REEs from ash having the steps of contacting ash with a first acid solution to generate leachate having a pH between approximately 5.0 and approximately 5.5; contacting the ash with a second acid solution to generate leachate having a pH between approximately 2.8 and approximately 3.5; and contacting the ash with a third acid solution to generate leachate having a pH between approximately ?0.6 and approximately 0.5. The invention also provides a method for leaching REEs from ash having the steps of: contacting ash with a first amount of acid sufficient to leach Ca and AJ from the ash without leaching REEs; contacting the ash with a second amount of acid sufficient to leach REEs from the ash without leaching Fe and Sc; and contacting ash with a third amount of acid sufficient to leach Fe and Sc from the ash.
    Type: Grant
    Filed: July 15, 2021
    Date of Patent: February 11, 2025
    Assignee: United States Department of Energy
    Inventors: Mengling Stuckman, Christina L. Lopano, Thomas Tarka
  • Step-Leaching Process of Rare Earth Elements from Ash Materials Using Mild Inorganic Acids at Ambient Conditions
    Publication number: 20220017992
    Abstract: The invention provides a method for extracting REEs from ash having the steps of contacting ash with a first acid solution to generate leachate having a pH between approximately 5.0 and approximately 5.5; contacting the ash with a second acid solution to generate leachate having a pH between approximately 2.8 and approximately 3.5; and contacting the ash with a third acid solution to generate leachate having a pH between approximately ?0.6 and approximately 0.5. The invention also provides a method for leaching REEs from ash having the steps of: contacting ash with a first amount of acid sufficient to leach Ca and AJ from the ash without leaching REEs; contacting the ash with a second amount of acid sufficient to leach REEs from the ash without leaching Fe and Sc; and contacting ash with a third amount of acid sufficient to leach Fe and Sc from the ash.
    Type: Application
    Filed: July 15, 2021
    Publication date: January 20, 2022
    Inventors: Mengling Stuckman, Christina L. Lopano, Thomas Tarka