Preparation of porous ceramics using CaCO3 as the foaming agent

Porous ceramics were synthesized by using oily soil and waste glass as the main materials, calcium carbonate as the foaming agent, and sodium silicate as the fluxing agent by controlling the sintering process. The samples were characterized by using XRD and SEM. The influence of the quantity of oily soil used on the porosity and flexural strength of samples were further evaluated. The results show that when the quantity of the oily soil increased, the porosity increased first and then decreased regularly, and the flexural strength decreased first and then increased. When the quantity of the oily soil was 40 wt%, the corresponding highest porosity was 69.44% and the lowest flexural strength was 2.16 MPa.