Granted Patent
Utility
US 5,494,869 · App. 08/219,625
Process for regenerating nitrogen-treated carbonaceous chars used for hydrogen sulfide removal
Inventors:
Richard A. Hayden, Steven L. BUTTERWORTH
Patented Case
View Patent ↗
Granted: Feb 27, 1996
Filed: Mar 29, 1994
Inventors
Richard A. Hayden
Steven L. BUTTERWORTH
Assignee (at issue)
CALGON CARBON 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.