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A porous ceramic membrane for the nano-filtration range was fabricated from a mixture of ball clay and starch. Sayong ball clay powders were mixed with starch as a pore former and compacted under a pressure of 200 MPa. The mixture was sintered at temperatures ranging from 900°C to 1200°C. It was found that the porous structure and crystalline phase of the sintered membrane were greatly dependent on the sintering temperature. The membranes exhibited bulk density varying from 1.5 g/cm 3 to 1.9 g/cm 3 , an apparent porosity ranging from 40.2% to 0.34%, an average pore size of 23.16 to 5.11 nm and flexural strength ranging from 1 to 21 MPa as the sintering temperature was increased. The pore size observed by SEM is much larger than these values, and these observed pores are believed to construct open channels that act as the main paths for filtration, as discuss later. The permeation flux greatly dependent on the transmembrane pressure and sintering temperatures. The membrane synthesized at 1050°C displayed the optimum properties as a nanofiltration membrane with a bulk density of 1.6 g/cm 3 , apparent porosity of 18%, pore size of 9.84 nm and flexural strength of 6 MPa.

The fabrication of low cost ceramic membranes for microfiltration were studied by using a natural materials (shirasu balloon) which are produced from glassy volcanic materials. The shirasu powder was formed into cylindrical shaped membranes and sintered at five different temperatures from 600 °C to 800 °C using spark plasma sintering (SPS). The porosity and density of membranes were measured according to Archimedes method. The effect of sintering temperatures on microstructure and phase of the membranes has been investigated using FESEM and XRD. A filtration experiment was carried out to study the membrane performance for waste water filtration. The quality of the filtered water was determined by analyse the pH, turbidity, suspended solid, chemical oxygen demand (COD) and biochemical oxygen demand (BOD5). The porosity reduced from 48.9% to 40.32% while the membrane density increased from 1.15 g/cm3 to 1.33 g/cm3 with increasing sintering temperatures from 600 °C to 800 °C. A little shrinkage occur during spark plasma sintering process. From the FESEM microstrcture, the maximum pore size of the membrane that has been observed at 600 °C is about 4.7 µm. Shirasu membrane are able to produce clean and clear treated water during the microfiltration test with membrane sintered at 800 °C and there is an improvement in quality of water that has been filtered. The ceramic water filter was successfully produced without the involvement of the high-tech, sophisticated machines and methods as well as complex materials

Microfiltration membrane made from Sayong ball clay by using uniaxial dry compaction method was used to treat natural organic matter (NOM) source water. A sintering temperature of 900 °C to 1000 °C were applied. The effect of sintering temperature on membrane porosity, strength and water flux were identified. The porosity of the membrane decreased with increasing sintering temperature and the strength and flux increased with temperature. The membrane was subjected to NOM filtration experiments. The results showed an improvement to the quality of permeate water, where there is a reduction in COD, TSS, BOD5, turbidity, hardness and salinity; and an increased pH value. The effect of chemical cleaning on the fouled membrane also was studied. After cleaning with NaOH solution, a high flux recovery was achieved (up to 50% from the initial pure water flux). The degree of cleanliness of fouled membranes after chemical cleaning was further observed with SEM and EDX analysis.

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