Nisar Ahmed

1. The membrane separation limit expresses the membrane's retention capacity for a specific component. The membrane separation limit depends on the pore diameter in the filter layer and the diameter of the molecule of the substance being retained. The accuracy of membrane filtration is determined by the pore size and pore size distribution. The filtration threshold is more or less blurred, since it is impossible to perform precise separation by molecular weight or molecule diameter.

2. The rate of component separation during membrane filtration depends on the characteristics of the membranes used, i.e., on the membrane thickness, its surface area, and pore diameter. The separation rate also depends on the operating parameters of the filtration modules, namely, pressure, pH, temperature, and hydrodynamic separation parameters.

3. Mechanical and thermal strength. In recent years, semipermeable membranes have been created from metal ceramics, glass, metal oxides, and some other materials. They have high mechanical strength, heat resistance (up to 200 °C), chemical resistance in the pH range from 0 to 14, resistance to high pressure, etc., which creates conditions for their long-term use.