PREPARATION OF POROUS CERAMIC MATERIAL FROM WASTE GLASS AND CALCINED KAOLIN USING YEAST AS PORE FORMING AGENT

Production of light-weight porous ceramic media from metakaolin and waste glass powder with sodium silicate as foaming agent in batch1 and without sodium silicate in batch 2 was investigated. Different weight percentages of yeast (0.1-0.5) as pore forming agent have been added to both batches. All samples were formulated by wet milled, dried, shaped and fired at 700°C for batch 1and at 850°C for batch 2. Chemical and mineralogical analysis, identification and calculation of crystalline to amorphous ratio phases by XRD, microstructure and mechanical and physical properties were investigated to specify the resulting porous article. The predominant closed porosity is found in batch 1 whereas open pores are prevalent in batch 2. The size of pores ranges from 3.794mm to 58µm in batch No. 1 and from 67.5 µm to 1.6 µm in batch No. 2 (millimeter to sub-micron) with approximately spherical shape were found in both batches.