Granted Patent
Utility
US 4,430,199 · App. 06/265,516
Passivation of contaminant metals on cracking catalysts by phosphorus addition
Inventors:
Vincent A. Durante, Dennis J. Olszanski, William J. Reagan, Stanley M. Brown
Patented Case
View Patent ↗
Granted: Feb 7, 1984
Filed: May 20, 1981
Inventors
Vincent A. Durante
Dennis J. Olszanski
William J. Reagan
Stanley M. Brown
Assignee (at issue)
Engelhard Corporation
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.