Mullite-Based Ceramics from Mining Waste: A Review

Abstract

Mullite (3Al2O3·2SiO2) is an aluminosilicate characterized by excellent physical properties, which makes it an important ceramic material. In this way, ceramics based on mullite find applications in different technological fields as refractory material (metallurgy, glass, ceramics, etc.), matrix in composite materials for high temperature applications, substrate in multilayer packaging, protective coatings, components of turbine engines, windows transparent to infrared radiation, etc. However, mullite is scarce in nature so it has to be manufactured through different synthesis methods, such as sintering, melting-crystallization or through a sol-gel route. Commonly, mullite is fabricated from pure technical grade raw materials, making the manufacturing process expensive. An alternative to lowering the cost is the use of mining waste as silica (SiO2) and alumina (Al2O3) feedstock, which are the necessary chemical compounds required to manufacture mullite ceramics. In addition to the economic benefits, the use of mining waste brings out environmental benefits as it prevents the over-exploitation of natural resources and reduces the volume of mining waste that needs to be managed. This article reviews the scientific studies carried out in order to use waste (steriles and tailings) generated in mining activities for the manufacture of clay-based ceramic materials containing mullite as a main crystalline phase.

Mechanical properties of in situ synthesized mullite‐based composite ceramics with three‐dimensional network structure

“…Coal gangue has become widespread with the development of the coal industry in China. Large amounts of coal gangue exist in the form of bulk industrial solid waste, resulting in environmental pollution 1–5 . Coal gangue can be considered as a potential mineral resource since it has a high content of aluminum and silicon oxides.…”

“…Large amounts of coal gangue exist in the form of bulk industrial solid waste, resulting in environmental pollution. [1][2][3][4][5] Coal gangue can be considered as a potential mineral resource since it has a high content of aluminum and silicon oxides. In recent years, as building materials, coal gangue can be used to prepare refractory bricks, filling of underground mined areas, cement, lightweight aggregate, and ceramsite.…”

Study of a Waste Kaolin as Raw Material for Mullite Ceramics and Mullite Refractories by Reaction Sintering

“…Several important industries use this kind of refractories, for instance iron and steel, cement, catalysts, petrochemicals, glass and many other advanced functional applications [20][21][22][23][24][25][26][27][28][29][30][31][32]. Thus, it is very important and a real problem the valorization of mining residues by the production of mullite-based ceramic materials [32][33][34][35][36][37][38][39][40][41]. This investigation is a contribution for this purpose.…”

Feasibility Study on the Potential Replacement of Primary Raw Materials in Traditional Ceramics by Clayey Overburden Sterile from the Prosilio Region (Western Macedonia, Greece)

“…Their uses have tripled since 1970, in accordance with mining excavations and/or drilling exploitations [1]. The mining activities alone produce a large amount of wastes, exceeding 100 billion tones/year, and they are responsible for about 50% of global greenhouse gas emissions [1,2]. These wastes include different materials, such as tailings, waste rocks (steriles), and slags, which all require appropriate treatment and management under the frame of environmental and economic sustainability [3].…”