Porous ceramic based on phlogopite from the polymeric sponge method

Porous ceramics are technologically great applicability materials, their characteristics and properties as mechanical resistance, low density and thermal conductivity, high surface areas make them attractive for use as filter media, catalytic support, thermal and acoustic insulation1-3. Its obtainment is by the conventional method of the PU polymeric sponge coated with ceramic suspension, posteriorly drought, calcined and sintered4. This method allows obtaining micrometric pores, with structure interconnected and identical to the substrate4. In this work, a porous ceramic based on phlogopite was obtained using the replica method. The methodology used in the production of the ceramic suspension (pH = 9) was: 25.0 g phlogopite, 1.0 mL NaSiO3 and 40.0 mL distilled water, a ball mill with a speed 600 rpm/24h. The sponge was measured and dipped to the ceramic suspension, the excess removed and dried at 25ºC. The samples were treated thermally at 400°C/1h, then calcined at 900°C and sintered at 1300°C/2h. The TG/DTG analysis, maximum mass loss occurred at 500ºC, by dilatometry, maximum sintering temperature occurred at 1200ºC and by MEV, the pores presented hexagonal and uniform geometries with 500μm. The obtained porous ceramic had good mechanical resistance and interconnected pores, regular and large.