Process for making high octane gasoline with reduced benzene content by benzene alkylation at high benzene conversion

US8395006B2 · kind B2 · utility

Assignee

• EXXONMOBIL RESEARCH AND ENGINEERING COMPANY · US

Inventors

• Michael C. Clark · Seabrook, US
• Benjamin S. Umansky · Fairfax, US
• Elizabeth A. Nye · Houston, US
• Mark J. REICHENSPERGER · Billings, US
• William Christopher Lewis · Burns Lake, CA

Key dates

• Filing date: Mar 9, 2010
• Grant date: Mar 12, 2013
• Expiry date: Sep 16, 2030

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/52
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

A process for the alkylation of a benzene-containing refinery stream such as reformate with light refinery olefins which is capable of achieving high benzene conversion levels operates in a fixed bed of an MWW zeolite catalyst, preferably MCM-22, in single pass mode in the liquid phase at a relatively low to moderate temperatures with pressure maintained at a value adequate to ensure subcritical operation. High levels of benzene conversion with conversions of at least 90% and higher, e.g. 92% or 95% or even higher are achievable. A high octane product is produced, comprising mono-, di- and tri-alkylbenzenes with lesser levels of the tetra-substituted products. By operating with staged olefin injection, the end point of the alkylation product can be maintained at a low value while, at the same time, achieving high levels of benzene and olefin conversion.