Thermal decomposition of barium valerate in argon

•The thermal decomposition of Barium valerate has been studied in Ar.•The compound melts in two steps prior to decomposition.•Solidification during decomposition results in stochastic gas release and mass loss.•5-nonanone and CO2 are the main evolving gas species.

The thermal decomposition of barium valerate (Ba(C4H9CO2)2/Ba-pentanoate) was studied in argon by means of thermogravimetry, differential thermal analysis, IR-spectroscopy, X-ray diffraction and hot-stage optical microscopy. Melting takes place in two different steps, at 200 °C and 280 °C and evidence was found for the solidification of the melt at 380–440 °C, i.e. simultaneously with the onset of decomposition. Between 400 °C and 520 °C (Ba(C4H9CO2)2 decomposes in two main steps, first into BaCO3 with release of C4H9COC4H9 (5-nonanone), whereas final conversion to BaO takes place with release of CO2. Elemental carbon that is left as a by-product is finally slowly burned by the residual oxygen present in the Ar atmosphere.