Surfactant can improve the agglomeration of ultrafine powder

2021-03-19 15:36:51

Surfactant molecular ordered assemblies have been widely used in various industrial fields due to their various practical functions, such as emulsification, solubilization, wetting, adsorption, permeation, dispersion, defoaming, thickening and lubrication.

It has been used in the production of traditional and special ceramics in ceramic industry. The preparation of ceramics generally has the following processes: powder preparation, powder mixing, molding, glazing and sintering, each step will affect the quality of ceramic products. Surfactant can improve the agglomeration of superfine powder, the uniformity of glaze and the performance of slurry. It has become the main additive in modern ceramic industry.

Surfactant can reduce the interfacial tension and make the wetting angle close to zero. Solid powder can be spontaneously dispersed in surfactant solution. At the same time, the surfactant can help the liquid to wet the inner surface of the solid, make the liquid penetrate into the channels and voids between the aggregates inside the particles, provide a certain pressure, and under the mechanical action, destroy the strengthening bond force of the aggregates.

At the same time, surfactant can help grinding, reduce the surface energy of particles, prevent the damaged surface from recovering bonding, so as to achieve the purpose of preventing particle coalescence. Surfactants as grinding aids also play a lubricating role, which can improve the specific surface area of products, shorten the grinding time and improve the grinding efficiency. The mechanism can be summarized as follows: reducing crushing energy, increasing brittle fracture probability, preventing plastic deformation, controlling flocculation and aggregation of fine particles, strengthening dispersion and adjusting rheological properties of slurry.

Hu Yongping used sodium petroleum sulfonate, sodium oleate surfactant and triethanolamine as grinding aids in superfine grinding of clay minerals. The results showed that the yield of 500 mesh could be increased from 76.5% to 84.9% when 0.155% sodium petroleum sulfonate was added.