Fractal characteristics of particle groups and mechanochemical effects of Yellow River sediment after mechanical grinding

Abstract

This paper investigated the fractal characteristics of particle groups and the mechanochemical effects of mechanically grinding Yellow River Sediment (MGYRS). The particle groups of MGYRS had good fractal characteristics, and the fractal dimension had a better correlation with the particle size, distribution and specific surface area of MGYRS, which could well reflect the changes in the physical properties of MGYRS. After mechanical milling, the analysis by XRD, FT-IR and XPS microscopic tests revealed that: the crystallinity and grain size of mineral crystals in MGYRS decreased with the increase in milling time. The electron binding energy of Si2p, Al2p and O1s shifted to the low-energy direction, and the chemical valence state of silicon atoms appeared Si3+ due to the breakage of the Si-O-Si/Al chemical bond. These changes in internal structure and chemical valence state were the microscopic manifestations of mechanochemical effects. The activation rate of MGYRS increased with the increase of grinding time, which was the macroscopic manifestation of mechanochemical effects.