Abstract
In thesis, I try to add silicalite into PDMS to form a composite membrane, and to see if it can effectively separate the A.A./water solutions. Also, by experimental data, this thesis studies the separation mechanism of pervaporation. We can find that the synthetic silicalite is an irregular crystalline via SEM. Its BET determined surface area is between 350 and 400 m2/g, conforming to the basic characteristics of porous zeolites. But via the PDSA analysis, we know the crystal is greater than 1μm in size. For the material property analyses, we observed the morphology of PDMS /silicalite composite membrane by SEM, and via TGA, we know that the decomposition temperature of the membrane is improved if we add silicalite into pure PDMS. From our experimental data, we know that at 45℃, with a silicalite content of 49.9%, the composite membrane efficiently improve the separation factor of A.A./water mixture over the pure PDMS membrane. At the A.A. feed concentration of between 5wt% and 40wt%, the separation factor (αA.A.) is between 1.84 and 2.29, and the flux is between 96.9 and 221 g/m2-hr. This result is better than that of the pure PDMS membrane. But at a silicalte content of 69.2%, the composite membrane is no longer dense but porous, giving no separation effect.