Prediction of flux and aroma compounds rejection in a reverse osmosis concentration of apple juice model solutions

The aim of this work was to predict the rejection of aroma compounds and pe rmeate flux during the reverse osmosis concentration of model solutions sim ulating apple juice. For the concentration, the MSCB2521 R99 spiral-wound m embrane (Separem SpA, Biella, Italy) was used. The preferential sorption-ca pillary flow model was employed for this purpose. Water and aqueous solutio ns of apple juice aroma were used to determine the parameters included in t he model. Then, the model was tested with aqueous solutions of glucose and aroma compounds. Experiments were performed at different transmembrane pres sures (1.5-3.5 MPa), feed flow rates (200-600 L/h; Reynolds numbers = 51-19 0), temperatures (15-30 degreesC), and glucose concentrations (9.1-17.0 deg rees Brix). Good agreement between experimental and estimated data was obse rved for most of the aroma compounds and operating conditions used.