Simplified optimization method using the MATLAB function fminbnd was adopted to determine the optimal feed temperature (OFT) for an isothermal packed-bed reactor (PBR) performing hydrogen peroxide decomposition (HPD) by immobilized Terminox Ultra catalase (TUC). The feed temperature was determined to maximize (minimize) the average reactant conversion (reactant concentration) over a fixed period time at the reactor outlet. The optimization was based on material balance and rate equation for enzyme action and decay and considered the effect of mass-transfer limitations on the system behavior. In order to highlight the relevance and applicability of the work reported here, the case of optimality under isothermal operating conditions is considered and the practical example is worked out. Optimisation method under consideration shows that inappropriate selection of the feed temperature may lead to a decrease in the bioreactor productivity.

The demand of energy and the search for alternative energy sources are the reason why scientists are interested in starch hydrolysis. The aim of the work was to experimental study of the hydrolysis of starch by α–amylase from porcine pancreas with α–amylase deactivation. Based on the experiments data, the parameters of starch hydrolysis by α– amylase with deactivation of enzyme was estimated. A mathematical model of temperature impact on the activity of α–amylase from porcine pancreas was used. It has been estimated that the activation energy E_a and the deactivation energy E_d were equal to 66 ± 4 kJ/mol and 161 ± 12 kJ/mol, respectively. Additionally, specific constant of starch hydrolysis k ₀ and specific constant of α–amylase deactivation k _d0 were calculated. The optimum temperature T_opt equal to 318 ± 0.5 K was obtained from mathematical model. The obtained values of E_a, E_d, k ₀ and k _d0 parameters were used to the model starch hydrolysis by α–amylase from porcine pancreas at 310 K and 333 K.