The effects of dissolved inorganic and organic matter in seawater and the characteristics of fouling on the membrane surface were investigated within membrane distillation (MD) process. The changes of the membrane flux of PE and PVDF hollow fiber membranes under natural and synthetic seawater were compared with given variances of temperature. The flux of both membranes under the synthetic seawater, without any organic matter, were higher than that of the natural seawater, indicating the organic fouling on the membrane surface. The surface of the membrane was analyzed using scanning electron microscope (SEM) to examine the fouling. The experiment with organics has shown the formation of thin film over the membrane surface, while the experiment with inorganics has shown only the formation of inorganic crystals. The results indicated the organic matter as the major foulants and that the organics affected the formation of the crystals. Permeate water conductivity of all conditions verified the quality of the water to be better if not similar to that of RO.

The preparation of CaSO4 nanoparticle by vesicles formed spontaneously in cationic OTAC and anionic ADS mixed surfactant solution whose ratio is 0.3/0.7 is investigated. Added electrolytes for preparing nanoparticles reduce vesicle size about 200-300 nm comparing with that of pure vesicle whose size is 700-800 nm by DLS. The core of vesicles has 200 nm size and acts as nanoreactors which same size of monodisperse CaSO4 nanopaticles are formed. Although CaSO4 particles are formed at the outer of vesicles, they are very large and amorphous. The formed particles are identified with XRD analysis after separation due to coinciding with CaSO4 particles.