Foam - The Gelling Preparation Of Porous Ceramic Balls

Porous ceramic was applied widely as a result of its excellentphysical and chemical properties, so the method of fabrication porousceramic was paid extensive attention, but the traditional methods havemany drawbacks. A method of multi-phase emulsion was used forpreparation of porous ceramic pellets in this paper. The project focusedon dispersion stability of sepiolite suspension, the method of fabricationof porous ceramic pellets and sintering. According to the principle ofmulti-phase emulsion, the Foaming-Gel technology was adopted toprepare porous ceramic pellets.The adsorption of sodium dodecylbenzenesulfonate (SDBS) onto aceramic slurry mixture composed of sepiolite suspension was investigatedin this study. Both adsorption isothermals and the average particle zetapotential were studied in order to understand the suspension stability as afunction of pH value and surfaetant concentration. The results showedthat SDBS under the optimal conditions such as 11of pH value, 0.8wt%of concentration, sepiolite slurry acquired fine dispersion stability.Through comparing ceramic slurry with different surfactants, many kindsof ceramic slurry had bad dispersion stability, but the ceramic clay withSDBS had better dispersion stability than other dispersants. So we choseSDBS as the surfactant.The important parameters of thermal treatment were determinedaccording to experiments. The thermal property of porous ceramic pelletsand ceramic clay at different temperature were detected via X-raydiffraction, simultaneous differential scanning calorimetry and thermalgravity analysis. The morphology of surface and diameter of the pelletwas characterized by SEM and digital camera. The results showed thatthe diameter of pellet is in the range of 1～4mm. The optimal parametersof thermal treating in oxidation atmosphere was 1100℃of temperature,20 min for heat preservation. The porous ceramic pellets with 0.08%foaming agent treated at 1100℃had physical properties, and the densityof pellets was 1.1～1.3g/cm~3 and the porosity was 60～75%.