An Assessment of a Logarithmic Nonisothermal Storage Test

AbstractThe expected biases in kinetic parameter estimates from a logarithmic nonisothermal storage test have been determined by simulation. The magnitude of the biases depends on heating rate, activation energy (E), and rate constant (k0). Typical errors are -10 to -15% in k0 and +0.5 to +1.0kcal per mole in E. An iterative linear solution is proposed to eliminate these errors.A nonisothermal storage test enables the activation energy and frequency factor of a reaction to be obtained from a single experiment. Several methods have been described which differ in their time-temperature relationships or in the numerical methods used for parameter estimation1-0. Within the pharmaceutical area the first of these methods was devised by Rogers (1963)1.In the Rogers″ method the temperature is programmed so that the reciprocal of the absolute temperature varies logarithmically with time:Substituting this into the Arrhenius and first-order equations and integrating yields:Rogers has suggested that the last term on ...