A comparative study of porous support from Sayong and Kankara clay

A porous supports were fabricated from Sayong ball clay and Kankara clay for wastewater treatment application using simple compaction method. The influence of sintering temperature (900-1200 °C) and starch addition (5-30 wt%) on the physical properties and flexural strength of the porous support were studied. Thermo-gravimetric analysis, particle size distribution, microstructure, phase, porosimetry analysis and strength analysis were studied to characterize the porous supports. The apparent porosity and pore diameter of Kankara porous support (48-55%; 6.62nm) was found to be higher than that of Sayong porous support (0.07-40%; 5.11nm). In contrast, the bulk density of Sayong porous support (1.15-1.93g/cm3) was higher than that of Kankara porous support (1.08-1.25g/cm3). However, the flexural strength of Kankara porous support (34-3MPa) shows sharp decrease compared with Sayong porous support (21-9MPa). This shows that Sayong porous support has better physical properties and flexural strength compared with Kankara porous support. Starch has been a good pore former in fabrication of the ceramic membrane. Sintering temperature and starch content have strong influence on the physical and flexural strength of the porous support. Therefore, the properties of the porous support can be varied by controlling the sintering temperature and starch content

Chemical cleaning of microfiltration ceramic membrane fouled by nom

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

Preparation of porous ceramic membranes from Sayong ball clay

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/cm3 to 1.9 g/cm3, 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/cm3, apparent porosity of 18%, pore size of 9.84 nm and flexural strength of 6 MPa

Study on fabrication of ceramic membrane from shirasu balloon for waste water filtration

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 material

Effect of starch addition on microstructure and strength of ball clay membrane

The use of starch as pore-forming agent is one of the frequently used methods to produce porous ceramics membrane with controlled microstructure (porosity and pore size) because corn starch are cheap, non- toxic and environmental friendly. A membrane with the mixture 0-35 wt% of corn starch and ball clay were prepared by compaction process and sintered at 1200°C. Thermal analysis has been done to identify the minimum sintering temperature for ball clay. The sintered membranes show the range value of shrinkage is 4.5-22.76% and apparent porosity of 9.14-31.83% depending on the starch content. The pore structures were analyzed by FESEM. The strength of sintered samples was tested by 3-point bending test. The flexural strength reduced from 21-7 MPa. These clay membrane are promising porous ceramic structure for water filtration applications due to their excellent combination physical and mechanical properties