In situ synchrotron powder diffraction study of the thermal decomposition of cement-asbestos: preliminary results

Abstract

The elimination of asbestos-containing materials like cement-asbestos, is an environmental priority. An industrial process for the safe recovery of cement-asbestos slates was recently developed and permits the thermal transformation of asbestos fibres into non-fibrous crystalline phases in a tunnel kiln. Optimisation of the process requires knowledge of the reaction dynamics. Here, time-resolved synchrotron powder diffraction was used to follow the thermal transformation of cement-asbestos. The use of a closed capillary as sample holder allowed to closely resemble the atmospheric conditions found in the industrial reactor. In this preliminary work, we describe the reaction sequence which undergoes cement-asbestos during its thermal decomposition. The excellent time resolution of the collected data allowed the observation of meta-stable phases at non-ambient conditions.