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The aim of this study was to investigate the thermal behaviour of cement-asbestos wastes and to determine whether it is possible to use them in the production of building ceramics, e.g. clinker bricks. In the first part of the research, the process of cement-asbestos thermal decomposition was studied. This asbestos material contained the chrysotile and crocidolite variety of asbestos. The results of this study allowed to determine the lowest temperature of thermal treatment that provides asbestos detoxification. The second part of the paper presents the results of a preliminary study on using previously calcined cement-asbestos wastes as an additive to ceramic masses typical for clinker bricks. Green compacts containing various amounts of cement-asbestos wastes were sintered and then ceramic properties were determined. The results of the study indicate that calcined asbestos-containing materials can be used as one of the secondary raw materials in the production of clinker ceramics.

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X-ray diffraction data revealed that the initial SiO2/Ag nanocomposite, manufactured in a chemical synthesis process, is mainly composed of silica in amorphous phase (95.5 wt.%), crystalline Ag with a cubic structure (Fm-3m) and cristobalite (SiO2) with a tetragonal structure (P41212) in the amount of 4.2 and 0.3 wt.%, respectively. High-temperature diffraction data revealed high stability of the SiO2/Ag composite up to 1000 °C. High-temperature X-ray diffraction measurements revealed phase cristallization temperatures of silica at 1060 °C for cristobalite and 1080 °C for tridymite as well as temperature of silver evaporation starting from the composite (ca. 1000 °C). Infrared spectroscopy data confirmed the presence of amorphous matrix with embedded silver ions and crystalline compounds in the form of cristobalite and tridymite without silver after thermal treatment.

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