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. 07, 2000
Filed:
Jun. 10, 1997
Tan-Jen Chen, Kingwood, TX (US);
Luc Roger Martens, Kingwood, TX (US);
Exxon Chemical Patents Inc., Houston, TX (US);
Abstract
The invention provides a process for improving the conversion of a hydrocarbon feedstock to light olefins comprising the steps of first contacting the hydrocarbon feedstock with a light olefin producing cracking catalyst and subsequently thermally cracking the unseparated stream to produce additional ethylene. Preferably the zeolite catalyst is selected from the group consisting of ferrierite, heulandite, phillipsite, faujasite, chabazite, erionite, mordenite, offretite, gmelinite, analcite, ZSM-5, ZSM-11, ZSM-25, gallium silicate zeolite, zeolite Beta, zeolite rho, ZK5, titanosilicate, zeolites having a silica to alumina molar ratio within the range of about 2.0:1 to 2000:1 ferrosilicate; zeolites such as those described in U.S. Pat. No. 4,238,318; borosilicate zeolites such as those described in Belgian Pat. No. 859656; zeolites designated by the Linde Division of Union Carbide by the letters of X, Y, A, L; zeolites such as those described in U.S. Pat. No. 5,552,035; and zeolites such as those described in U.S. Pat. No. 5,348,924. Preferably the catalyst is contacted at a temperature within the range of about 500.degree. C. to about 750.degree. C. and the feedstock flows at a weight hourly space velocity in the range of about 0.1 Hr.sup.-1 WHSV to about 100 Hr.sup.-1 WHSV. The trim thermal cracking is carried out between 650.degree. C. to 900.degree. C. for 0.1 to 20 seconds.