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.