Title of article :
Process performances and characteristics of powders produced using supercritical CO2 as solvent and antisolvent
Author/Authors :
Subra، نويسنده , , P. and Berroy، نويسنده , , P. and Vega، نويسنده , , A. and Domingo، نويسنده , , C.، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2004
Pages :
10
From page :
13
To page :
22
Abstract :
A carbon dioxide (CO2) soluble compound (cholesterol) was successfully precipitated either by rapid expansion of SCCO2 solutions (RESS process, acronym for Rapid Expansion of Supercritical Solution), or from methylene chloride solutions by antisolvent precipitation (SAS-process, acronym for Supercritical Antisolvent process). The same fluid was thus used either as a solvent or as an antisolvent to precipitate cholesterol. Performances of RESS and SAS were compared through the analysis of the particle characteristics and production rates. Differences were related to supersaturation and time scale of nucleation/growth involved in both processes. Polydispersity, large size and elongated shape were characteristics of particles produced by SAS, especially when experiments were performed under conditions of total miscibility of CO2 and organic solvent. Conditions where vapor–liquid equilibrium exists promoted a confinement of the growth that consequently reduced the final particle size. RESS, by comparison, produced smaller and monodispersed particles. Production of small particles is a key advantage for RESS, but lower production rates and yield might be disadvantages. The combination of the two processes offers the opportunity of tunable sizing of powder, switching from a large production of particles ranging from 10 to 100 μm, to a limited production of fine crystals below 10 μm.
Keywords :
Antisolvent , solvent , Cholesterol , Precipitation , Carbon dioxide
Journal title :
Powder Technology
Serial Year :
2004
Journal title :
Powder Technology
Record number :
1693630
Link To Document :
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