RHI Magnesita is the leading global supplier of high-grade refractory products, systems and solutions which are critical for high-temperature processes in a wide range of industries. With a vertically integrated value chain, RHI Magnesita serves customers around the world, with around 15,000 employees in 47 production sites, 7 recycling facilities and more than 70 sales offices. 

To lead sustainable development in refractory industry, RHI Magnesita is working to optimize the use of raw materials in alignment with circular economy best practices. 

For this to be possible, in some cases it is necessary to pre-treat circular minerals (recycled refractory products returning from customer) in order to ensure the properties required for final application. This is the case, for example, of raw materials with high alkali content, which need to be removed before use. 

The recycling raw materials are, in fact, refractory bricks with varied chemical composition, but divided in two groups: magnesian (>75% MgO) and non-basic(>60%Al2O3). Other compounds include metal oxides such as SiO2, Fe2O3, CaO, among others. 

Alkalis occur in this matrix as Na/K salts and sulfates are also present. The content of these compounds can reach up to 3%. They come from the thermal processes in which refractory are used. In these environments, the alkalis are volatilized and infiltrate the bricks. Upon reaching the coldest parts of the refractories, the alkalis are reprecipitated in the form of salts. 

We are eager to partner with experts in refractories but also welcome collaborations with researchers and companies focused on adjacent spaces, such as ceramics, composites, construction, mineral processing, extractive metallurgy and mining.