The present study
evaluates the transportation, leaching, and stabilization
ability of novel saponin extracted from the fruits of Acacia auriculiformis. To enhance the dispersing
behavior of the fly ash slurry (FAS) at a lower dosage of sodium silicate, A. auriculiformis was incorporated in FAS. In addition
to the rheological study, an attempt has been made to remove heavy
metals through leaching for the safe disposal of FAS. Critical factors
such as the fly ash (FA) concentration, saponin dosage, surface tension,
ζ potential, temperature, and combination of saponin and sodium
silicate, affecting the rheology of FAS, were extensively studied.
The addition of a nonionic natural surfactant saponin has been proved
to enhance the wettability of FA particles by decreasing the surface
tension of FAS. The obtained rheology results were compared with the
stabilization yield of the previously reported commercial surfactant
cetyltrimethylammonium bromide. The incorporation of sodium silicate
in the FAS system was found to be phenomenal in the settling and stabilization
of FAS, thereby developing reaction products like sodium aluminum
silicate (N-A-S). This facilitates the sustainable disposal of FA
preventing air pollution after dewatering. The formation of N-A-S
was further supported by scanning electron microscopy (SEM) and X-ray
diffraction (XRD) studies.