Monitoring and modelling of variables affecting isomerate octane number produced from an industrial isomerization process

Petroleum refineries are now facing much tighter and stricter transportation and fuel specification standards, as well as environmental regulations, than in previous years. Therefore, tough rules have been applied on gasoline specifications. Octane number is a key variable of gasoline quality. Isomerization is one of many processes that generate profit by increasing low gasoline octane numbers, with better environmental impacts compared to other processes. Here we analyzed and optimized the various variables affecting the isomerate octane numbers produced by isomerization. Feed composition (naphthenes and benzene content in the feed) and operating conditions (temperature, hydrogen consumption and liquid hourly space velocity) data were collected from the Midor isomerization plant (Egypt) over a 4-year period based on the catalyst lifetime. These data were then used to predict the influence of feed composition and operating conditions on isomerate research octane number using a Response Surface Methodology (RSM) approach (Design Expert software). Thus, we were able to predict isomerate research octane number under various operating conditions. All of the studied variables were found to influence octane number. Keywords: Isomerization process, Operating variables, Octane number, Gasoline