Study On The Dispersion Of Collophanite Fines

In this graduation thesis, four species of dispersing agent—sodium silicate, sodiumhexametaphosphate, sodium tripolyphosphate and sodium pyrophosphate—wereinvestigated wholly by the sedimentation and liquid removal experiment, as well as otherpotential factors such as pH of dispersion media and stirring speed. Meanwhile, thedispersion behavior and mechamism of collophanite fines were analysed by the measuringof surface potential and wetting contact angle.The results of the experiment indicate that compared with sodium hydroxide, sodiumcarbonate has an obvious effect on the dispersion of collophanite fines. While in the samecondition, the rate of dispersion could be greatly increased by sodium pyrophosphate,followed by sodium tripolyphosphate, sodium hexametaphosphate and sodium silicate.And the effect of dispersion agent is beyond the pH of dispersion media. When the dosageof dispersion agent is enough, the rate of dispersion is steady although the pH keeps anupward trend. After a certain speed, the dispersion rate is steady.As the statistic of measuring inferred, the surface potential and wetting contact angleare the significant factors of dispersion mechamism. The rate of dispersion keeps anupward trend while the absolute value of surface potential increases or the wetting contactangle decreases. On the contrary, the surface tension fluctuates around the value of surfacetension of distilled water although the rate of dispersion changes significant.