METHOD FOR PRECIPITATING FINELY DIVIDED SOLID PARTICLES

摘要

The method involves: a) dissolving a compound (C) in a fluid (A) to obtain a solution (A); b) thermostatizing said solution (A) at a temperature ranging between -50~ C and 200~ C; c) adding a fluid (B) to said solution (A) until pressure (P) is attained, whereby the invention is characterized in that the fluid (B) at pressure (P) is miscible with said solution (A) and acts as co- solvent to form solution (AB) and d) reducing pressure of said solution (AB) so that precipitation of said compound (C) will not take place. The method makes it possible to obtain medium-size particles of less than 20 .mu.m, generally less than 10 .mu.m, with a narrow size distribution ranging between 1 and 100 .mu.m, generally between 1 and 20 .mu.m, from a solution and not from a mixture, which contains the compound to be precipitated.