disintegration otherwise dispersion; comminution (rus. диспергирование) — a fine pulverisation of solids or liquids, leading to formation of disperse systems: powders, suspensions, emulsions, and aerosols.

Description

The dispersion of liquids in gases is usually called spraying, whereas the dispersion of a liquid in another liquid (not mixing with the first one) is called emulsification. The specific work required for dispersion depends on the cohesive characteristics, structural features of the pulverised body and the desired degree of pulverisation, and the surface (interfacial) energy. Introduction of surface-active materials, dispersants and emulsifiers, reduces energy expenditure for dispersion, improves the degree of dispersion of the pulverised phase and stability of the disperse system. Dispersion under high mechanical loads, especially that of solids, is often accompanied by physical and chemical processes that lead to profound changes in the composition, structure and properties of the dispersed solid bodies (see mechanochemical treatment). Depending on the composition and properties of the dispersed phase and dispersion medium and on the method of dispersion, the lower particle size limit of the pulverised body can range from several tens of micrometres to tens of nanometres (for spontaneous dispersion – to several nanometres).

Authors

  • Smirnov Andrey V.
  • Shlyakhtin Oleg A.

Source

  1. Dispergation // Chemical encyclopedia (in Russian). V. 2. — Moscow: Sovetskaja ehnciklopedija, 1990. - 77 p.

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