Abstract: A process for preparing crystalline particles of an active principal in the presence of ultrasonic irradiation that comprises contacting a solution of a solute in a solvent in a first flowing stream with an anti-solvent in a second flowing stream causing the mixing thereof, wherein the flow rate ratio of the anti-solvent: solvent is higher than 20:1, and collecting crystals that are generated.

Abstract: This invention provides an oscillating baffled reactor apparatus for preparing crystalline particles of at least one substance comprising: a reactor vessel; means for supplying a first flowing stream; means for oscillating fluid within the reactor vessel; a plurality of baffles; source of ultrasonic radiation; and means for collecting said particles.

Abstract: A process for preparing an emulsion or a dispersion comprising crystalline particles of at least one active principal that comprises contacting a solution of at least one solute in a solvent or mixture of solvents in a first flowing stream with a non-solvent in a second flowing stream wherein the non-solvent and solvent are not miscible with each other, so as to form an emulsion or a dispersion. Super saturation is brought about by suitable means, and the emulsion or dispersion is subjected to ultrasonic irradiation to mediate crystal nucleation.

Abstract: A process for preparing crystalline particles of an active principal in the presence of ultrasonic irradiation that comprises contacting a solution of a solute in a solvent in a first flowing stream with an anti-solvent in a second flowing stream causing the mixing thereof, wherein the flow rate ratio of the anti-solvent: solvent is higher than 20:1, and collecting crystals that are generated.