Patents by Inventor Risto Harjula

Risto Harjula 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).

  • Publication number: 20210148024
    Abstract: The invention relates to a new use of spun, continuous inorganic fibers having a diameter smaller than 1 ?m in the form of monolithic structures with at least one dimension equal to or greater than about 50 ?m. The monolithic structures are formed by self-entanglement of the continuous fibers as an ion exchange material. In particular the invention relates to a new ion exchange material bed comprising such fibers and ion exchange unit comprising such bed. The invention improves the efficiency and sustainability of ion exchangers.
    Type: Application
    Filed: May 24, 2018
    Publication date: May 20, 2021
    Inventors: Risto Harjula, Risto Koivula, Mikko Ritala, Eero Santala, Jani Holopainen, Esko Tusa
  • Patent number: 6214234
    Abstract: A method for removal of cesium from aqueous solution, particularly from nuclear waste liquids. The cesium-containing aqueous solution is contacted with a solid-state hexacyanoferrate compound of a transition element for binding cesium to the hexacyanoferrate. The aqueous solution of reduced cesium content is separated from the hexacyanoferrate. Preferably, a nickel or cobalt hexacyanoferrate is utilized having a fraction of exchangeable transition elements smaller than 35 %. The hexacyanoferrate compound of said transition element may be produced by slowly adding an aqueous solution of the hexacyanoferrate into the transition element salt solution, the concentration of the transition element salt solution being at least 0.35 mol/l, stirring the mixture at ambient temperature during the addition, and separating and recovering the resulting hexacyanoferrate precipitate from the mixture.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: April 10, 2001
    Assignee: Ivo Power Engineering Oy
    Inventors: Risto Harjula, Jukka Lehto
  • Patent number: 6106799
    Abstract: A titanate ion exchanger and method of producing same. Solid hydrous titanium oxide in a slurry is reacted with an alkaline agent, such as NaOH, containing an exchangeable cation. A solids fraction containing the titanate product is settled and separated and a granular titanate ion exchanger product recovered from the solids fraction. The ion exchanger is suitable for the separation of radionuclides, such as those containing radioactive strontium, from nuclear waste solutions.
    Type: Grant
    Filed: December 11, 1996
    Date of Patent: August 22, 2000
    Assignee: Ivo International Ltd.
    Inventors: Jukka Lehto, Heikki Leinonen, Risto Harjula