The effect of CaF2 addition on the processing of CaO - Al2O3 – SiO2 based ceramics properties from waste

In this study, the effect of CaF2 additive on the properties of CaO – Al2O3 – SiO2 (CAS) based ceramics from granulated blast furnace slag, thermal power plant waste fly ash, boron production waste, waste glass, and magnesite refractory production waste mixtures was investigated. Compositions were prepared by adding 0, 3, 6, 9, and 12% by weight CaF2 to the mixture of granulated blast furnace slag; thermal power plant fly ash, boron production waste, magnesite refractory waste, and waste glass. Cylindrical samples were shaped by pressing and sintered at 900, 950, 1000, 1050 and 1100 °C for 2 hours and characterized. For this purpose, microstructures with scanning electron microscopy (SEM) and phase analyses with X-ray diffraction (XRD) were made, and firing shrinkage, bulk density, apparent porosity, water absorption, freezing, cottonization properties, and compression strength values of sintered samples were determined. Thus, the effects of CaF2 additive on the properties of ceramics produced from mixtures of granulated blast furnace slag, thermal power plant fly ash, boron production waste, magnesite refractory waste, and waste glass powder were investigated. It was observed that the CaF2 additive caused a decrease in the amount of pores and water absorption values with the increase of the sintering temperature and an increase in the density values. The results showed that CAS-based ceramics produced from waste mixtures could be used as building materials.