Development and experimental checking of an unsteady-state model for ultrafiltration continuous tank reactors

A mathematical model applicable to the analysis, design and simulation of homogeneous enzymatic processes reacting in a ultrafiltration membrane reactor has been formulated. The model develops the unsteady-state design equations, including a first-order model to represent enzyme deactivation kinetics. To check the model, the stereospecific hydrolysis of N-acetyl- DL-butyrine catalysed by L-aminoacylase to give L-butyrine and unmodified N-acetyl- D-butyrine was used as an experimental system. The experiments were carried out at pH 7.0 and 50 ∘ C , using two different flow rates (1.0 and 1.5 cm 3 min - 1 ), three different substrate concentrations at the reactor inlet (25, 50 and 100 mmol dm - 3 in N-acetyl- L-butyrine ( C SL 0 ) ) and two different start-up modes. When the experimental data were compared to those theoretically predicted, the statistical analysis underlined the goodness of the model and the accuracy of the constants calculated.