The fly ash, from the combustion of coal to produce energy and heat, is an industrial waste, in which large accumulations represent a serious environmental threat. To reduce the environmental burden and improve the economic benefits of energy production, the science and industry focus on the transformation of coal combustion byproducts into new functional materials. The fly ash was studied by modern analytical methods. As a result of the hydrothermal reaction, several types of zeolites were synthesised from the fly ash: analcime, faujasite (zeolite X) and gismondine (zeolite P). It was shown that the experimental conditions (temperature, reaction time and alkali concentration) have a significant influence on the type of zeolite and its content in the reaction products. The series of experiments resulted in building approximate crystallisation field of zeolites and other phases as the first stage of the formation of ceramic membrane and other materials.

DOI: 10.31897/PMI.2022.43 The growing demand for mullite raw materials, which meet industrial requirements originates the search for new and alternative sources, as well as efficient technologies for obtaining the target products (nanocomposites). The article suggests a method for obtaining mullite from kaolinite experimentally (Vezhayu-Vorykvinsky deposit, Russia)....