Solvent · low polarity
Methyl isobutyl ketone C6H12O
Also: MIBK
GC/HPLC solvent of moderate polarity; low water solubility makes it a preferred solvent for liquid-liquid extraction and sample cleanup (e.g. extraction of metals as chelates, organic analytes from aqueous matrices) prior to GC or AAS/ICP; extraction/back-extraction in residue analysis; general medium-polarity solvent for resins, coatings and nitrocellulose. High UV cutoff (334 nm) makes it unsuitable for low-wavelength UV/HPLC detection.
Compiled by Hemant RawatLast reviewed July 2026How we verify
Properties
- Formula
- C6H12O
- CAS number
- 108-10-1
- UV cutoff
- 334 nm
- Snyder polarity index (P′)
- 4.2
- Selectivity group
- VIa
- Eluotropic strength ε° (silica)
- —
- Boiling point
- 115.7 °C
- Viscosity (25 °C)
- 0.545 cP
- Refractive index (nD²⁰)
- 1.3962
- Density
- 0.7965 g/mL
- Water miscibility
- partial
- USP <467> class
- Class 2
Safety
- highly flammable (H225, flash point ~14-18 C, autoignition ~448 C)
- eye irritant (H319)
- harmful if inhaled (H332)
- may cause drowsiness/dizziness - CNS narcotic (H336)
- suspected carcinogen (H351; IARC Group 2B)
- not a significant peroxide former (unlike ethers)
Reference only. Solvents can be flammable, toxic, or peroxide-forming. Always consult the Safety Data Sheet (SDS) and your lab's protocols before handling.
What Methyl isobutyl ketone mixes with
Miscible with: 1-Propanol, 1,2-Dichloroethane, 1,4-Dioxane, 2-Propanol, Acetic acid, Acetone, Acetonitrile, Benzene, Carbon tetrachloride, Chloroform, Cyclohexane, Dichloromethane, Diethyl ether, Dimethyl sulfoxide, Ethanol, Ethyl acetate, Iso-octane, Methanol, Methyl ethyl ketone, MTBE, n-Butanol, n-Butyl acetate, n-Heptane, n-Hexane, N-Methylpyrrolidone, n-Pentane, N,N-Dimethylacetamide, N,N-Dimethylformamide, Pyridine, tert-Butanol, Tetrahydrofuran, Toluene, Triethylamine.
Immiscible with: Water — these form two layers.
Check any specific pair on the interactive miscibility chart.
Using Methyl isobutyl ketone in HPLC/GC
GC/HPLC solvent of moderate polarity; low water solubility makes it a preferred solvent for liquid-liquid extraction and sample cleanup (e.g. extraction of metals as chelates, organic analytes from aqueous matrices) prior to GC or AAS/ICP; extraction/back-extraction in residue analysis; general medium-polarity solvent for resins, coatings and nitrocellulose. High UV cutoff (334 nm) makes it unsuitable for low-wavelength UV/HPLC detection.
Its Snyder polarity index is 4.2 (selectivity group VIa), and its UV cutoff of 334 nm limits low-wavelength UV detection.See what the polarity index means and the full UV cutoff table.
Sources
- University of Toronto (TRACES) — Burdick & Jackson — Solvent UV cutoff table (absorbance = 1 AU, 1 cm cell)
- Stenutz / L. R. Snyder — Solvent polarity index (P′) and selectivity groups
- NIST — Chemistry WebBook — thermophysical properties (BP, density, refractive index)
- PubChem (NIH/NLM) — Compound property records (physical constants, CAS, formula)
- USP <467> / ICH Q3C — Residual Solvents — solvent classification (Class 1/2/3)
Values are compiled from public references and were last verified July 2026. See ourmethodologyfor how we source and verify. Always confirm critical values against primary references and the SDS.
Related solvents
Other selectivity group VIa to compare with Methyl isobutyl ketone.