$16.\_\_\_\_\_\_\_\_\_\_$ distillation is a technique used to break azeotropes in the solvent recovery phase, ensuring the purity of recovered solvents for future extraction cycles.

$17.$ Supercritical fluid extraction utilizes $\_\_\_\_\_\_\_\_\_\_$ as a solvent, which exhibits unique properties that allow for efficient extraction at temperatures and pressures above its critical point.

$18.$ The $\_\_\_\_\_\_\_\_\_\_$ of a solvent impacts its ability to penetrate the feed material and dissolve solutes, affecting the overall efficiency of the extraction process.

$19.$ Solvent extraction processes are designed to maximize the $\_\_\_\_\_\_\_\_\_\_$ of the target component, ensuring that the most valuable part of the feed is recovered.