Preparation and Characterization of Nanostructured Materials from Fly Ash: A Waste from Thermal Power Stations

The Class F fly ash has been subjected to high energy ball milling and has been converted into nanostructured material. The nanostructured fly ash has been characterized for its particle size by using particle size analyzer, specific surface area with the help of BET surface area apparatus, structureby X-ray diffraction studies and FTIR, SEM and TEM have been used to study particle aggregation and shape of the particles. On ball milling, theparticle size got reduced from 60 lm to 148 nm by 405 times and the surface area increased from 0.249 m2/gm to 25.53 m2/gm i.e. by more than 100%.Measurement of surface free energy as well as work of adhesion found that it increased with increased duration of ball milling. The crystallite wasreduced from 36.22 nm to 23.01 nm for quartz and from 33.72 nm to 16.38 nm for mullite during ball milling to 60 h. % crystallinity reduced from35% to 16% during 60 h of ball milling because of destruction of quartz and hematite crystals and the nano structured fly ash is found to be moreamorphous. Surface of the nanostructured fly ash has become more active as is evident from the FTIR studies. Morphological studies revealed that thesurface of the nano structured fly ash is more uneven and rough and shape is irregular, as compared to fresh fly ash which are mostly spherical in shape.

Preparation and Characterization of Nanostructured Materials from Fly Ash: A Waste from Thermal Power Stations Keywords:

High energy ball mill , Fly ash , Nanostructured materials , Quartz , Mullite