Petroleum Refining: Conversion

Petroleum conversion is the final step in the petroleum refining process.

Petroleum conversion can be broken down into three separate chemical processes: Decomposition, alteration, and unification. Decomposition processes involve the use of thermal or catalytic methods to crack large hydrocarbon molecules into smaller, more valuable hydrocarbons. Alteration processes are used to make small changes to hydrocarbon molecules, resulting in a product with more desirable and valuable properties such as a higher octane number. The unification process uses chemical reactions to combine smaller liquid and gaseous hydrocarbons into medium length molecules. By combining these processes in various configurations, refineries are able to produce a relatively consistent product from a wide range of raw material compositions.


"Petroleum Refining Process." OSHA Technical Manual. Section IV: CHapter 2. United States       Department of Labor, Occupational Safety & Health Administration, n.d. Web. 13 Mar.       2016.

Speight, James G. The Chemistry and Technology of Petroleum. 4th ed. Boca Raton: CRC       Press, 2007. Print.

Photo Credits

Sierra Monitor Corporation , Milpitas, CA

Monroe Environmental Corporation , Monroe, MI

ROBATEL, Inc. , Pittsfield, MA


Jackson Irwin