In situ Raman spectroscopy of the decomposition of tertiary butyl peroxy pivalate under high pressure and high temperature

The decomposition of tertiary butyl peroxy pivalate (TBPPI), in n-hexane, u nder a pressure of 1900 bar and at a temperature of 100 degreesC, was studi ed in situ with the use of a transportable high-throughput fiber-optic Rama n spectrometer. The Raman probe was conveniently coupled to an optical high -pressure cell containing the TBPPI, Time-resolved experiments with a 10 wt % solution of TBPPI in n-hexane were carried out, and information on the m echanism of decomposition and the (first-order) kinetics was obtained, It i s shown that the main decomposition products of TBPPI are CO, and t-butanol , From first-order kinetic fits, of the Raman profiles of intensity vs. tim e of reactants and products, the rate constant for the decomposition of TBP PI and the formation of CO, is found to be 1.65 . 10 (3)s (1) (half-life ti me for TBPPI of approximately 420 s). t-Butanol formation occurs at a slowe r rate of approximately 1.22 . 10 (3)s (1) (characteristic time of 566 s).