The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 05, 2019
Filed:
Apr. 06, 2016
Univation Technologies, Llc, Houston, TX (US);
Brandon C. Locklear, Houston, TX (US);
R. Eric Pequeno, Baytown, TX (US);
Richard B. Pannell, Kingwood, TX (US);
Fathi David Hussein, Hilton Head Island, SC (US);
Rich John Stolz, Baytown, TX (US);
William A. Matthews, Hilton Head Island, SC (US);
Univation Technologies, LLC, Houston, TX (US);
Abstract
A method for transitioning a gas phase polymerization reactor between metallocene catalysts is provided. The method comprises first reducing the superficial gas velocity and increasing the height of the fluidized bed within the reactor prior to stopping a feed comprising a first metallocene catalyst. The method further comprises introducing a first polymerization neutralizer to the reactor, wherein the first polymerization reactor does not comprise water, and then introducing a second polymerization neutralizer to the reactor, wherein the second polymerization neutralizer is different from the first polymerization neutralizer. After this, the method comprises purging the reactor with an inert gas and then introducing a feed comprising a second metallocene catalyst to the reactor.