The plastic/toluene mixture is cooled slightly so that the low density polyethylene (LDPE) can reform into a solid. Some evaporating toluene condenses on the ceiling of the holding container, is funneled on the slanted surface, and is piped back to the toluene supply.

Because one plastic is a solid and one plastic is dissolved in a liquid, the two separate very nicely. This holding container is slanted slightly, so the liquid runs off into a distilling container. This container is where the toluene is distilled, or evaporated, and is reused in the manufacturing process. The fast evaporation rate of the toluene makes distillation a quick process. In fact, toluene is one of the most commonly used industrial solvents because of the fast evaporation rate.

The original solid (when the plastic and toluene were still mixed) is LDPE. The plastic left after toluene distillation is polypropylene.

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