Influences of Bentonite Modification Methods on the Physical and Chemical Properties of Bentonite

The current study focuses on the artificial modification of natural bentonite using pulping sodium, stacking sodium, extrusion sodium, wheel rolling sodium, and microwave sodium treatments. The effects of these methods on the physical and chemical properties of bentonite are investigated. The results indicate that the wheel rolling sodium treatment, which features the effects of extrusion and kneading, facilitated maximum separation and sodium treatment of Ca2+ and Mg2+ in the lattice of bentonite. This method produced highly efficient Ca-bentonite with full modification. When the wheel rolling sodium treatment was performed for 60 min, the modified bentonite exhibited a colloid index of 300 mL/3 g, swelling value of 275 mL/2 g, swelling volume of 94 mL/g, and 2 h water absorption of 755%. The modified bentonite has desirable cohesiveness, dilatability, suspension property, dispersibility, and high physical and chemical performances, which are suitable for use as iron ore concentrate pallet and casting bentonite binders.