Nanosized ZnS particles were synthesized in bis(2-ethylhexyl) suffosuccinate (AOT) reverse micelles and then recovered by dissolving compressed CO2 into the micellar solution. The size of the obtained ZnS nanoparticles can be tailored in the range of 1-100 nm by varying the experimental conditions. The particles' size decreases with increasing pressure of CO2. The size of the particles recovered at 308.2 K is smaller than that of the particles recovered at 298.2 K. Stirring of the solution in the recovery process can reduce the particle size effectively. Increase in molar ratio of water to AOT (w) results in an increase in the particle size. However, the effect of the concentration of AOT in the micellar solution on the size of the products is very limited. (C) 2003 Elsevier B.V. All rights reserved.