General kinetic observations overall rate coefficient

2 GENERAL KINETIC OBSERVATIONS OVERALL RATE COEFFICIENT 

The wall-effect was investigated by Winkler and Hinshelwood . They concluded that the thermal decomposition of acetone is almost completely homogeneous in a seasoned vessel. 

However, according to Allen , surface increase (/) completely altered the shape of the rate versus pressure curves, (i7) had practically no effect at high temperatures and high pressures, though considerably reduced the rate for instance at 465 °C, and Hi) eliminated the induction period which occurred in an empty vessel. The observations of Allen concerning the induction period and the effect of surface/volume ratio show, without doubt, that the decomposition of acetone is a complex process. 

The first-order rate coefficients and the Arrhenius parameters determined at higher pressures (generally above 100 torr) agree reasonably well, as can be seen from Table 6 and Fig. 5. The straight line drawn by the least-squares method through the points of the Arrhenius plot gives the first-order rate coefficient as 

ARRHENIUS PARAMETERS OF ACETONE PYROLYSIS, DETERMINED AT INITIAL PRESSURES HIGHER THAN 100 TORR 

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