Light Naphtha Isomerization Process: A Review

The isomerization process is gaining importance in the present refining context due to limitations on gasoline benzene, aromatics, and olefin contents. The isomerization process upgrades the octane number of light naphtha fractions and also simultaneously reduces benzene content by saturation of the benzene fraction. Isomerization complements catalytic reforming process in upgrading the octane number of refinery naphtha streams. Isomerization is a simple and cost-effective process for octane enhancement compared with other octane-improving processes. Isomerate product contains very low sulfur and benzene, making it ideal blending component in refinery gasoline pool. Due to the significance of isomerization to the modern refining industry, it becomes essential to review the process with respect to catalysts, catalyst poisons, reactions, thermodynamics, and process developments. The present research thrust in this field along with future scope of work is also discussed briefly. The isomerization process is compared with another well-known refinery process called the catalytic reforming process.