Characteristics of functional water retaining porous ceramics prepared from waste diatomite and waste ceramics tiles

Abstract

This paper reports on the use of waste ceramics tiles and waste diatomite in the synthesis of a novel porous ceramics construction material (WRPC) for moisture retention. Experiments were performed to elucidate the impact of sintering temperature (1000 °C–1200 °C) and the proportion of waste ceramics tiles (0 %–40 %) on mechanical properties and water absorption performance. The crystalline phases and constituent minerals were identified using X-ray diffraction and Fourier transform infrared spectroscopy. The proportion of waste ceramic material in the mix was positively correlated with volume shrinkage and inversely correlated with porosity. Sintering temperature was positively correlated with density and compressive strength, and negatively correlated with porosity and water absorption capacity. The primary crystal phase in the WRPC was identified as cristobalite, the intensity of which decreased with an increase in the content of material derived from waste ceramics tile. Under high heating temperatures, all of the quartz in the WRPC samples transformed into cristobalite, resulting in good chemical and thermal stability. The WRPC samples exhibited high compressive strength (>3 MPa), high water absorption capacity (>0.15 g/m2), and slow water-releasing behavior (t1/2 = 4.1−17.3 h). Experiment results confirmed that waste ceramic tiles and waste diatomite could be transformed into construction materials of practical value.