The heat and mass transfer processes in direct contact membrane distillation (MD) under laminar flow conditions have been analyzed by computational fluid dynamics (CFD). A two-dimensional heat transfer model was developed by coupling the latent heat, which is generated during the MD process, into the energy conservation equation. In combination with the Navies-Stokes equations, the thermal boun...

Xanthan gum is a polysaccharide that is widely used as stabilizer and thickener with many industrial applications in food industry. Our aim was to estimate the ability of Xanthomonas campestris ATCC 13951 for the production of xanthan gum by using whey as a growth medium, a by-product of dairy industry. X. campestris ATCC 13951 has been studied in batch cultures using a complex medium for the d...

It could be shown by the reduction of the spin label (1,14) located within DPPC vesicles, that Na-ascorbate and K-isoascorbate can permeate membranes. At physiologic pH value, these two compounds exist as electroneutral radicals with a cyclic side chain structure. Ascorbic acid and isoascorbic acid, on the contrary, can hardly permeate such an artificial membrane. Since the radical will cause l...

The effects of operating parameters such as feed temperature and permeate-side pressure on the performance of a commercial PVA membrane in the dehydration of toluene by a pervaporation (PV) membrane system is studied in the present work. The results obtained indicate that increasing temperature in the range of 40 to 70 °C and reducing permeate pressure in the range of 1 to 10 mmHg increase memb...

Microfiltration can clarify pomegranate juice; however, fouling is a limiting phenomenon in the process. In current work ultrasound was applied above and below the membrane surface to reduce fouling after removing temperature effect. A hydrophilic mixed cellulose ester membrane with pore size of 0.45 μm was used in lab scale flat sheet module. Membrane module was placed above and below the ultr...