Patents by Inventor Willem Dijkstra

Willem Dijkstra 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: 20230108558
    Abstract: Star-shaped ceramic body, wherein the cross-section of the body has six lobes, the ratio of the maximum radius r2 in the star to radius r1 of a circle connecting the intersections of the lobes being in the range from 1.0 to 3.61, preferably from 2.17 to 3.61, the ratio of the area F1 inside this circle to the summed area F2 of the lobes outside this circle being in the range of from 0.54 to 0.90, the ratio of the distance x2 between the two intersections I of one lobe with neighboring lobes and the radius r1 of the circle being in the range of from 0.67 to 1.11. The ceramic body is used as catalyst-support.
    Type: Application
    Filed: February 4, 2021
    Publication date: April 6, 2023
    Inventors: Robert TERORDE, Harry BOUWMAN, Willem DIJKSTRA, Stefan LIPP, Matthias Georg SCHWAB
  • Patent number: 11547981
    Abstract: A method for producing a three-dimensional porous transition alumina catalyst monolith of stacked catalyst fibers, comprising: a) Preparing a paste in a liquid diluent of hydroxide precursor particles and/or oxyhydroxide precursor particles of transition alumina particles, all particles in the suspension having a number average particle size in the range of from 0.05 to 700 ?m, b) extruding the paste nozzle(s) to form fibers, and depositing the extruded fibers to form a three-dimensional porous catalyst monolith precursor, c) drying the precursor to remove the liquid diluent, d) performing a temperature treatment of the dried porous catalyst monolith precursor to form the transition alumina catalyst monolith, wherein no temperature treatment of the porous catalyst monolith precursor or porous catalyst monolith at temperatures above 1000° C. is performed and wherein no further catalytically active metals, metal oxides or metal compounds are applied to the surface.
    Type: Grant
    Filed: May 28, 2019
    Date of Patent: January 10, 2023
    Inventors: Matthias Georg Schwab, Esther Groeneveld, Peter Berben, Harry Bouwman, Willem Dijkstra, Bart Michielsen, Jasper Lefevere
  • Publication number: 20210213423
    Abstract: A method for producing a three-dimensional porous transition alumina catalyst monolith of stacked catalyst fibers, comprising the following steps: a) Preparing a suspension paste in a liquid diluent of hydroxide precursor particles or oxyhydroxide precursor particles of transition alumina particles or mixtures thereof and which suspension can furthermore comprise a binder material in a maximum amount of 20 wt %, based on the amount of hydroxide precursor particles or oxyhydroxide precursor particles of transition alumina particles or mixtures thereof and/or a plasticizer and/or a dopant in a maximum amount of 10 wt %, based on the amount of hydroxide precursor particles or oxyhydroxide precursor particles of transition alumina particles or mixtures thereof, all particles in the suspension having a number average particle size in the range of from 0.
    Type: Application
    Filed: May 28, 2019
    Publication date: July 15, 2021
    Inventors: Matthias Georg SCHWAB, Esther GROENEVELD, Peter BERBEN, Harry BOUWMAN, Willem DIJKSTRA, Bart MICHIELSEN, Jasper LEFEVERE
  • Publication number: 20080051616
    Abstract: The invention is directed to a process for the hydrogenation of hydrocarbon resins in the presence of a precious metal catalyst, wherein the hydrogenation is performed in the additional presence of at least one metal oxide, capable of reacting with sulfide and/or halogen.
    Type: Application
    Filed: September 5, 2007
    Publication date: February 28, 2008
    Inventors: Bernard Reesink, Willem Dijkstra
  • Patent number: 7285695
    Abstract: The invention is directed to a process for the hydrogenation of hydrocarbon resins in the presence of a precious metal catalyst, wherein the hydrogenation is performed in the additional presence of at least one metal oxide, capable of reacting with sulfide and/or halogen.
    Type: Grant
    Filed: November 1, 2000
    Date of Patent: October 23, 2007
    Assignee: Engelhard Corporation
    Inventors: Bernard Hendrik Reesink, Willem Dijkstra
  • Patent number: 6855245
    Abstract: The invention is directed to a process for the hydrogenation of a sulfur containing feedstock, having a sulfur content of less than 50 ppm, wherein the feedstock is hydrogenated in the presence of a precious metal catalyst and a nickel-catalyst, said process being carried out in such a manner, that the feedstock is contacted with a mixture of precious metal catalyst, metal oxide and nickel catalyst, the feedstock is contacted initially with the precious metal catalyst followed by contact with the metal oxide and nickel catalyst, either in combination or sequentially, or the feedstock is contacted first with a mixture of precious metal catalyst and metal oxide, followed by contact with the nickel catalyst.
    Type: Grant
    Filed: July 20, 1999
    Date of Patent: February 15, 2005
    Assignee: Engelhard Corporation
    Inventors: Bernard Hendrik Reesink, Willem Dijkstra, Pieter Hildegardus Berben, Marius Vaarkamp