Influence of the cleaning temperature on the permeability of ceramic membranes

Membrane separation technologies applied to protein purification is an interesting development that has seen growth in recent years. However, studies about the long-term effects of the cleaning stage, considering different chemical agents and operating conditions, on the performance of the membranes are scarce in the literature. The purpose of this study was to evaluate experimentally the effect of a caustic–surfactant solution (the most commonly used for protein cleaning) at three different cleaning temperatures (30, 50 and 60°C) upon a 300 kDa tubular ceramic membrane. To this end, 15 repeated fouling and cleaning cycles with a mixture of model proteins, β-lactoglobulin and BSA, were performed. The cleaning temperature of 50°C was found to be the optimal due to: (a) its capability to restore the permeability to the initial values after each operating cycle, (b) the higher yield regarding protein separation. A process of membrane pore erosion was found for the cleaning temperature of 60°C.