Isooctane (2,2,4-Trimethylpentane)

About This Product

Isooctane is the common name of 2,2,4-trimethylpentane, formula C8H18 and CAS number 540-84-1, a highly branched eight-carbon paraffin. It is a clear, colourless liquid boiling at about 99 °C, insoluble in water and fully miscible with hydrocarbons. Its branched structure makes it exceptionally resistant to autoignition, and for that reason it was chosen to define 100 on the octane scale, with n-heptane at zero: every octane rating is a comparison against blends of the two. Engine and fuel laboratories therefore need material whose purity is beyond question, and this grade is specified at 99 percent minimum 2,2,4-trimethylpentane, typically 99.9, with light components, aromatics, olefins as bromine index, sulphur and water all held to tight limits. The same low reactivity and transparency to ultraviolet light make it a standard analytical solvent, specified for example in the acetic acid–isooctane method for peroxide value and in the anisidine value method for fats and oils. It is used in primary reference fuels for octane rating, as an analytical and spectroscopic solvent, in fats and oils testing, as a non-polar solvent and extractant, and as a raw material in organic synthesis. Bio Green Chem supplies isooctane at 99.9 percent purity to specification on 2,2,4-trimethylpentane content, light components, aromatics, bromine index, sulphur, water, non-volatile matter, distillation range, aniline point and density, in 142 kg drums or ISO tanks. It is highly flammable and an aspiration hazard; handle to the safety data sheet.