Patents by Inventor Belma Demirel

Belma Demirel 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: 20090069451
    Abstract: A method of producing an iron catalyst for catalyzing the hydrogenation of carbon monoxide is disclosed. The method comprises using a reduced amount of acid for iron dissolution compared to certain previous methods. The resulting acidic iron mixture is heated without boiling to obtain a nitrate solution having a Fe2+:Fe3+ ratio in the range of about 0.01%:99.99% to about 100%:0% (wt:wt). Iron phases are precipitated at a lower temperature compared to certain previous methods. The recovered catalyst precursor is dried and sized to form particles having a size distribution between 10 microns and 100 microns. In embodiments, the Fe2+:Fe3+ ratio in the nitric acid solution may be in the range of from about 3%:97% to about 30%:70% (wt:wt) and the calcined catalyst may comprise a maghemite:hematite ratio of about 1%:99% to about 70%:30%.
    Type: Application
    Filed: August 11, 2008
    Publication date: March 12, 2009
    Applicant: RENTECH, INC.
    Inventors: Belma Demirel, Charles B. Benham, Jesse W. Taylor, Pandurang V. Nikrad, Sara L. Rolfe, Olga P. Ionkina, Dawid J. Duvenhage, Harold A. Wright
  • Publication number: 20090062108
    Abstract: A method of strengthening a precipitated unsupported iron catalyst by: preparing a precipitated unsupported iron catalyst containing copper and potassium; adding a solution comprising a structural promoter to the previously prepared catalyst; drying the mixture; and calcining the dried catalyst. A method for preparing an iron catalyst, the method comprising: precipitating a catalyst precursor comprising iron phases selected from hydroxides, oxides, and carbonates; adding a promoter to the catalyst precursor to yield a promoted precursor; drying the promoted precursor to yield dried catalyst; and calcining the dried catalyst, wherein the catalyst further comprises copper and potassium. A method of preparing a strengthened precipitated iron catalyst comprising: co-precipitating iron, copper, magnesium, and aluminum; washing the precipitate; alkalizing the precipitate; and drying the precipitate to yield a dried catalyst precursor.
    Type: Application
    Filed: August 26, 2008
    Publication date: March 5, 2009
    Applicant: RENTECH, INC.
    Inventors: Belma Demirel, Charles B. Benham, Dan Fraenkel, Richard A. Bley, Jesse W. Taylor, Sara L. Rolfe, Harold A. Wright
  • Publication number: 20080223046
    Abstract: A method for meeting both base-load and peak-load demand in a power production facility. By integrating a Fischer-Tropsch (FT) hydrocarbon production facility with an electrical power generating facility, peak-load power demand can be met by reducing the temperature of the FT reactor thereby increasing the quantity of tail gases and using FT tail gases to fuel a gas turbine generator set. The method enables rapid power response and allows the synthesis gas generating units and the FT units to operate with constant flow rates.
    Type: Application
    Filed: December 21, 2005
    Publication date: September 18, 2008
    Inventors: Dennis L. Yakobson, Claude C. Corkadel, Charles B. Benham, Belma Demirel, Peter S. Pedersen
  • Publication number: 20080038159
    Abstract: Solvent extraction is used to remove wax and contaminants from an iron-based Fischer-Tropsch catalyst in a natural circulation continuous-flow system. The wax-free catalyst is then subjected to controlled oxidation to convert the iron to its initial oxidized state, Fe203. Reactivation of the oxide catalyst precursor is carried out by addition of synthesis gas.
    Type: Application
    Filed: October 18, 2007
    Publication date: February 14, 2008
    Applicant: RENTECH, INC.
    Inventors: Belma Demirel, Mark Bohn, Charles Benham, James Siebarth, Mark Ibsen
  • Patent number: 7303731
    Abstract: Solvent extraction is used to remove wax and contaminants from an iron-based Fischer-Tropsch catalyst in a natural circulation continuous-flow system. The wax-free catalyst is then subjected to controlled oxidation to convert the iron to its initial oxidized state, Fe2O3. Reactivation of the oxide catalyst precursor is carried out by addition of synthesis gas.
    Type: Grant
    Filed: December 7, 2004
    Date of Patent: December 4, 2007
    Assignee: Rentech, Inc.
    Inventors: Belma Demirel, Mark S. Bohn, Charles B. Benham, James E. Siebarth, Mark D. Ibsen
  • Publication number: 20050196332
    Abstract: Solvent extraction is used to remove wax and contaminants from an iron-based Fischer-Tropsch catalyst in a natural circulation continuous-flow system. The wax-free catalyst is then subjected to controlled oxidation to convert the iron to its initial oxidized state, Fe2O3. Reactivation of the oxide catalyst precursor is carried out by addition of synthesis gas.
    Type: Application
    Filed: December 7, 2004
    Publication date: September 8, 2005
    Inventors: Belma Demirel, Mark Bohn, Charles Benham, James Siebarth, Mark Ibsen
  • Patent number: 6838487
    Abstract: Solvent extraction is used to remove wax and contaminants from an iron-based Fischer-Tropsch catalyst in a natural circulation continuous-flow system. The wax-free catalyst is then subjected to controlled oxidation to convert the iron to its initial oxidized state, Fe2O3. Reactivation of the oxide catalyst precursor is carried out by addition of synthesis gas.
    Type: Grant
    Filed: December 4, 2003
    Date of Patent: January 4, 2005
    Assignee: Rentech, Inc.
    Inventors: Belma Demirel, Mark S. Bohn, Charles B. Benham, James E. Siebarth, Mark D. Ibsen