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Membrane reactors could serve as a tool for enzyme-catalyzed reactions and they enable the performance of catalytic reaction, enzyme recovery and product isolation as a one-step process. In the presented work, the use of continuous flat-shape and continuous tubular membrane enzymatic reactors for different enzymatic systems at atmospheric pressure and at supercritical conditions are described. In a high-pressure continuous enzymatic flatshape membrane reactor, where supercritical carbon dioxide (SC-CO2) was used as a solvent, the high-pressure enzyme-catalyzed hydrolysis of sunflower oil was performed. The influence of enzyme concentration and temperature on the production of total free fatty acids and especially oleic acid in biphasic (SC-CO2/H2O) medium were investigated. In the same type of reactor hydrolysis of soybean oil at atmospheric pressure was also performed. The application of tubular ceramic membranes in the high-pressure reaction system was studied on hydrolysis of carboxy-methyl cellulose (CMC) at atmospheric pressure and in biphasic (SC-CO2/H2O) medium. The reaction was catalyzed with covalent linked cellulase from Humicola insolens on the surface of ceramic membrane. The physical characteristics for tubular ceramic membranes before and after immobilization of enzyme onto membrane were defined, as well.

Hydrolase-catalyzed reactions were performed in two different types of continuous operated high-pressure enzymatic membrane reactor; in HP CEFSMR and in HP CETMR. Enzyme-catalyzed hydrolysis of soybean oil performed in CEFSMR at atmospheric pressure was successfully continuously run for 9 h and steady state was achieved already after 2 h of reaction and was constant till the end of reaction performance. The highest amount of total free fatty acids in permeate was achieved at temperature of 323 K. Enzyme-catalyzed hydrolysis of sunflower oil was successfully performed in biphasic (SC-CO2/H2O) medium in HP CEFSMR. Influence of enzyme concentration zc and temperature on free fatty acids production was investigated. The highest activity of lipase preparation from A. niger in biphasic (SC-CO2/ H2O) medium at 20 MPa was obtained at enzyme concentration of 0.017 g/mL and temperature 323 K. In both cases of using continuous operated flat-shape membrane reaction for performance of enzyme-catalyzed reaction at atmospheric pressure as well as in biphasic (SC-CO2/H2O) medium, polysulfon membrane was successfully used as a separation unit. Influence of enzyme immobilization technique on tubular membrane characteristics was studied. Decrease in pore diameter of tubular membrane after enzyme immobilization was observed. Therefore, selection of proper membrane for a defined reaction system should be done before enzyme immobilization due to approximately 90% decrease in membrane pore diameter after immobilization. The application of tubular ceramic membranes in the high-pressure reaction system was studied on hydrolysis of CMC at atmospheric pressure and in biphasic medium (SC-CO2/H2O). Reaction was catalyzed with covalent linked cellulase from H. insulens on the surface of ceramic membrane. Reaction carried out in biphasic medium gave higher productivity than reaction, performed at atmospheric pressure. Benefits of using SC-CO2 along with enzymatic catalysis are its favourable transport properties that can accelerate masstransfer-limited enzymatic reactions. Because of reduced mass-transfer limitations an increase in the reaction rate of the reaction performed at high pressure could appear.