Solid supported evaporation (SSE) is a simple, nonselective
method
for isolating nonvolatile compounds from a solution. The solution
is put in contact with porous polymer beads onto which the compound
deposits upon evaporation of the solvent. This brings some advantages
over direct evaporation to dryness in terms of safety, thermal decomposition,
and solid handling, as the loaded beads form a free-flowing granular
material that is easily recovered. In this paper, SSE in a semicontinuous
operating mode is investigated where the solution is continuously
fed to (respectively sprayed over) an agitated bed of dry beads put
under vacuum. It is found that under conditions where the solvent
evaporation rate is high with respect to the feed rate, high bead
loadings can be achieved before extensive sticking of beads and compound
to the vessel walls occurs. The type of compound and solvent had little
influence on the process performance, and, in cases where this was
explored, the bead loading was found to be homogeneous. Based on a
balance equation for the solvent fed to the system, a model is developed
that results in a simple scale up criterion. The latter was successfully
applied for transferring SSE from lab to the kilo lab scale.