Isolation and identification of oxide nanoparticles in fly ashes from Turkish thermal power plants and investigation of their potentials as fillers in polymeric nanocomposites

Fly ash is the waste product of combustion of coal in a thermal power plants. Approximately 800 million tons of fly ash can be produced world wide and this number is expected to increase with the increase the number of thermal power plants. The recycling of fly ash is around 15% worldwide. The impact of these wastes on environmental pollution cannot be underestimated, and for this reason recycling is a global problem. More than 17 million tons of fly ash are produced every year in Turkey and only 16.7% of this amount is used in construction and asphalt sector. The presence of nano and microparticles in fly ash contains the use of these materials as a filler material in high-tech materials. This has led to the need to explore the potential of the return of fly ash to the positive growth of the country's economy. We had developed simple, versatile and economical technique to fractionate oxide based nanoparticles (ONPs) from fly ashes. We obtained selectively SiO2 and Fe3O4 NPs enriched fractions. Total recovery of Fe3O4 and SiO2 were 53.46% and 55%, respectively. In addition, ham fly ash has been successfully removed from heavy metals such as Ga2O3, PbO and ZrO. Furthermore, homogeneously dispersed nanocomposite films in polypropylene(PP) is prepared by using SiO2(content 0.5%-1.5%, and, 2.5%-5% weight).Chemical identification of NPs were conducted with XRF and XPS for structural and chemical analysis, while particle size/size distribution was characterized by TEM and dynamic light scattering. Effective surface areas were measured by Braunnet-Emmet-Teller (BET) analysis. A twin screw extruder was used for nanocomposite preparation. The tensile and bending strength of all nanocomposites were increased. While the impact resistance of the nanocomposites were decreased.The elastic modulus varied with the composition and temperature. Light aerogels have been obtained from silica-rich fly ash which have been removed from harmful heavy metals and increased specific surface areas. In summary, Fe3O4 and SiO2 -enriched Fe3O4 and SiO2 ONPs obtained from fly ash were efficiently recovered from NPs, and a product potential for use as an industrially related product was investigated.