What is Isobutylene?

Isobutylene is a chemical compound that usually is used in the production of high octane fuel and in the preparation of organic compounds. The chemical structure is C₄H₈. Related compounds include isobutene, 2-methylpropene, and 1-dimethylethylene. At room temperature, isobutylene is a gas, and it becomes a liquid at extreme low temperatures. It is classified as a hazardous material by the U.S. Department of Transportation.

Production of isobutylene can be accomplished through separating the compound from sulfurized isobutylene. Sulfurized isobutylene is heated and then treated with acid which separates the isobutylene from the sulfur molecules. These chemicals then usually are purified with gaseous isobutylene which removes the sulfur molecules. The resulting isobutylene typically is then 99-percent pure.

Butanes, which are related compounds, usually are produced during the production of gasoline. This is accomplished by causing the butanes to react with isobutylene or by combining the two molecules to form octenes. Octenes are used to produce octane for gasoline production. Isobutylene also is used in the production of plastics, and comprises 98-percent of the raw materials used in the production of synthetic rubber.

Special precautions usually are required when working with and storing this material. Isobutylene gas is highly flammable, and it should not be exposed to any open flames, sparks, or come into contact with any oxidizing materials. Smoking usually is not allowed near the gas. Gas and air mixtures are highly explosive; if isobutylene reacts with the oxygen in the air, it can cause an explosion. Precautions typically include using a closed-ventilation system, using non-sparking hand tools, and making sure all electrical equipment is properly grounded.

Exposure to human contact can carry some risks. At room temperature, skin contact is unlikely but can result in irritation. Inhalation of the gas can cause dizziness, drowsiness, dullness, nausea, vomiting, and unconsciousness. Frostbite may result if skin comes in contact with isobutylene in its liquid state. If inhalation or ingestion occurs, it usually is recommended that immediate medical attention should be sought.

Storage of the gas and liquid form typically requires a fireproof container. It can be important to keep it separated from any oxidizing agents to help prevent possible fire or explosion. When disposing of isobutylene, it can be a good idea to always consult an expert. Since it is a hazardous chemical, it should never be disposed of in a sewer system or water supply. Usually, a chemical protection suit with a self-contained breathing apparatus should be used when disposing of the material after any ignition sources have been eliminated.