Granted Patent
Utility
US 5,877,331 · App. 08/968,172
Prevention of catalyst attrition and tar formation in manufacture of maleic anhydride
Inventors:
Michael J. Mummey, Robert A. Keppel, A. Lamar Reeves
Patented Case
View Patent ↗
Granted: Mar 2, 1999
Filed: Nov 12, 1997
Inventors
Michael J. Mummey
Robert A. Keppel
A. Lamar Reeves
Assignee (at issue)
HUNTSMAN PETROCHEMICAL LLC
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.