Technologies

Geopolymers are synthetic inorganic polymers obtained from an aluminosilicate powder and an aqueous solution of alkaline hydroxides or silicates. The material is mesoporous and a multidimensional and functional porosity can be generated through the addition of fillers or the use of specific techniques.

The mix-design of the mixture, pure or composite, allows to change the chemical-physical properties of the final material, also thanks to the nucleation of zeolitic phases. Geopolymers also possess ion exchange and electrostatic interaction capabilities.

The proposed technology is about the development of an innovative sunscreen obtained from cod fish bones, according to the principles of the circular economy. The sunscreen is a reddish powder, which is constituted of hydroxyapatite (a calcium phosphate main component of human bones) modified with iron. It is prepared with a simple and easily scalable process (treatment of the bones in Fe solution and successively at T = 700 oC) and could be adapted for bones of other fishes. 

Geopolymers belong to the class of chemically bonded ceramics: they are synthesized at low temperatures and are eco-friendly, as besides the low consolidation temperature required by the process they can be produced from secondary raw materials and industrial waste of various kinds, thus reducing the energy demand and the environmental impact of the entire production cycle. Materials such as fly ash, steel mill slag, biomass ash, sludge and silt, extractive residues, mineral and ceramic powders, organic or inorganic waste fibers, plastics, etc.