多分散土壤胶体颗粒的聚集

The dispersion and coagulation of soil colloidal particles concern highly with their mobility and activity, as well as the role played in biogeochemical cycle of elements. Particle size is an important factor that affects both the van der Waals potential energy and electrostatic potential energy. However, the size effect of soil particles on surface charge properties and suspension stability has rarely been investigated. Results showed that the zeta potentials (in absolute values) of soil colloidal particles (CP, particle diameter less than 1000?nm) were higher than soil nanoparticles (NP, particle diameter less than 100?nm) for the same solution pH, while the specific surface area of soil NP was 1.6 times of soil CP; taken together, the surface charge density of soil NP was smaller than that of soil CP and the surface charge number of soil NP was slightly higher than soil CP. The stability of soil NP and CP was also different.