Advances in Methods for Recovery of Ferrous, Alumina, and Silica Nanoparticles from Fly Ash Waste

Ceramics

MadhusudanHiraman Fulekar¹  VirendraKumar Yadav² 

[1] School of Environment & Sustainable Development, Central University of Gujarat, Gandhinagar, Gujarat 382030, India;School of Nanosciences, Central University of Gujarat, Gandhinagar, Gujarat 382030, India;

关键词: fly ash;    ferro-alumino-silicate (FAS);    alumina;    silica;    zeolites;    ferrous;   

DOI  :  10.3390/ceramics3030034

来源: DOAJ

【 摘 要 】

Fly ash or coal fly ash causes major global pollution in the form of solid waste and is classified as a “hazardous waste”, which is a by-product of thermal power plants produced during electricity production. Si, Al, Fe Ca, and Mg alone form more than 85% of the chemical compounds and glasses of most fly ashes. Fly ash has a chemical composition of 70–90%, as well as glasses of ferrous, alumina, silica, and CaO. Therefore, fly ash could act as a reliable and alternative source for ferrous, alumina, and silica. The ferrous fractions can be recovered by a simple magnetic separation method, while alumina and silica can be extracted by chemical or biological approaches. Alumina extraction is possible using both alkali- and acid-based methods, while silica is extracted by strong alkali, such as NaOH. Chemical extraction has a higher yield than the biological approaches, but the bio-based approaches are more environmentally friendly. Fly ash can also be used for the synthesis of zeolites by NaOH treatment of variable types, as fly ash is rich in alumino-silicates. The present review work deals with the recent advances in the field of the recovery and synthesis of ferrous, alumina, and silica micro and nanoparticles from fly ash.

【 授权许可】

Unknown