What Is Isobutyl Alcohol?
Isobutyl alcohol (IBA), a branched-chain alcohol, has the structural formula (CH3)2CHCH2OH and a molecular weight of 74.12. It is a clear, colorless liquid at room temperature with a characteristic odor similar to that of magic ink or markers. IBA is almost insoluble in water but soluble in most organic solvents.
In IUPAC nomenclature, isobutyl alcohol is more formally known as 2-methyl-1-propanol, although ‘isobutyl alcohol’ is widely accepted in industrial and patent publications. Its isomers include 1-butanol, 2-butanol, and tert-butyl alcohol.
Naturally, isobutyl alcohol is a major component of tea leaves, like black and green tea, and is also found as an aromatic ingredient in various foods such as fruits.
| Chemical formula | C4H10O |
| English name | 2-Methyl-1-propanol |
| Molecular weight | 74.12 |
Uses of Isobutyl Alcohol
Isobutyl alcohol is primarily used as a raw material in organic synthesis. It serves as the starting material for isobutyl acetate, used in lacquers, and paints, and as a flavoring agent in the food industry. Isobutyl acetate is noted for its pungent, fermented-like odor at high concentrations.
Additionally, IBA is used in the production of various chemical esters, including isobutyl acrylate, isobutyl phthalate (DIBP), and isobutyl methacrylate, which are used as plasticizers in plastics and rubbers, and as dispersing agents. It is also a solvent in chemical reactions, paints, and inks, reducing the viscosity of paint and preventing oil separation. Furthermore, IBA is added to gasoline as a cleaner and used in waxes and cleaning products.
IBA can be directly applied to fuel blendstocks, and it can be blended with or substituted for high-octane gasoline, ethanol, and other oxygenated fuel compounds. It is also a raw material for fragrances, pharmaceuticals, and analytical reagents, and is increasingly used in biofuel production, particularly in Sustainable Aviation Fuel (SAF), which can significantly reduce carbon dioxide emissions.
Properties of Isobutyl Alcohol
Isobutanol is a primary alcohol with properties similar to its isomer 1-butanol. It has a melting point of -108°C, a boiling point of 108°C, a flash point of 30°C, and a specific gravity of 0.8 g/mL (at 25°C). Its refractive index is n20/D 1.40, and it is liquid at room temperature. Isobutanol is miscible with many organic solvents like ether and alcohol, with a water solubility of 87 g/L (at 20°C).
Other Information on Isobutyl Alcohol
1. Isobutyl Alcohol Production Process
Isobutanol is produced by the reduction of isobutyraldehyde ((CH3)2CHCHO), formed by hydroformylation of propylene (CH2CHCH3). It is also a fermentation product of carbohydrates and a decomposition product of industrial chemicals.
2. Legal Information
Isobutanol is classified as an inflammable liquid and petroleum, non-water soluble liquid under the Fire Service Law.
3. Handling and Storage Precautions
Handling and storage precautions for isobutanol include:
- Storing in a cool, well-ventilated place with the container tightly closed.
- Using explosion-proof equipment and avoiding heat, sparks, and other ignition sources.
- Use only in well-ventilated areas or outdoors.
- Wearing protective gloves and glasses, and avoiding inhalation of mists or vapors.
- Washing hands thoroughly after handling and taking precautions against ignition by electrostatic discharge.
- Removing contaminated clothing and washing skin under running water if exposed.
- Rinsing eyes cautiously with water for several minutes in case of eye contact.