Abstract: An object of this invention is to provide a fine powder of diamond particles of less than 50 nm with a narrow particle size range. The diamond is single crystalline and characterized with a lot of sharp edges and sharp points. Another object is to provide a method for efficiently producing such fine powder. The method comprises mechanically crushing a raw material of single crystalline diamond particles to prepare starting minute particles of diamond, then imparting hydrophilic quality to the surface of diamond particles. As hydrophilic the diamond particles are dispersed in water to form a slurry, which is set and kept weakly alkaline. The slurry is then subjected to a preliminary grading step, whereby the slurry is removed of a top particle size fraction of the diamond particles that has a D50 size of 60 nm or more. Eliminated of said top particle size fraction, the slurry is then diluted with water to regulate the diamond concentration to 0.1% (by weight) or less.

Abstract: The invention concerns a process for separating and/or precipitating of solid and/or liquid particules (disperse phase) from gaseous and/or liquid media (continuous phase) as well as for separating mixed gases (gas-gas-separation) and/or mixed fluids (fluid-fluid-separation) as well as for screening and/or classifying by means of a vortex chamber separator with suction tube 35. For decrease of flow resistance at generation of moment of momentum the contact zone between main flow and eddy is adjusted to cylinder casing that the tangential initial impulse in laminary bottom flow is increased by means of decrease of laminary bottom flow impulse, secondarily circulating in vortex chamber. For reduction of loss of impulse by means of dissipative drop of pressure in flow of main channel, laminary bottom flow is dynamically balanced with constant or mainly constant average main flow rate.