On the extraction of oil from raw comminuted cottonseed kernels with the acetone-hexane-water azeotrope

The effects of particle size on the rate of ex‐traction of oil from raw comminuted cottonseed kernels with the acetone‐hexane‐water azeotrope were examined. Five samples of cottonseed of different average particle sizes and three extrac‐tion times were used in the investigation. The particles were comminuted in such a manner as to be, as a first approximation, essentially spher‐ical in shape; the concentration gradient of oil in the particles was found to follow the relationship L =r‐A +B where L is the oil content of the extracted seed, r is the particle radius, and A and B are constants. The establishment of the concentration gradient was extremely rapid (within 10 seconds), and the constants A and B assume the same values for each of the three extraction times employed. These two facts in‐dicate that mass oil movement in the particles is a dilatation and occurs too rapidly for diffusion phenomena to be evident.