High strength porous ceramics and its potential in adsorption and building materials: A short process to co-disposal secondary aluminum dross and quicklime

Abstract

Porous ceramics with hierarchical pore and high strength were prepared by secondary aluminum dross and quicklime as main raw materials. The influence of quicklime content and thermal treatment on the porosity, pore morphology, compressive strength and bulk density of porous ceramics has been investigated. Scanning electron microscopy, computed tomography, x-ray diffraction and thermal analysis were used to characterize the microstructure, phase transition and high-temperature reaction of the samples. The formation temperature of the liquid phase in the micro-region starts at around 973 °C, close to the temperature at which the mixture starts to produce the liquid phase as calculated by FactSage7.1 software. The achieved porous ceramics exhibited excellent compressive strength of 12.4–51.0 MPa at a relatively high porosity of 63.7%-79.6%. Furthermore, the potential application of the obtained porous ceramics as adsorbent was verified by the adsorption of malachite green solution. Due to the high connectivity of the pores and the presence of a large number of thin lamellar crystalline phases, the adsorption rate of the sample to malachite green solution can be as high as 98.4%.