distillation is a technique that uses a rotating helical band to
create a high number of theoretical plates. The spinning bands can
be made of Teflon or metal. Teflon spinning bands are used for distillations
below 225 °C. Metal bands are used for higher temperature distillations
where Teflon would become soft.
All distillations attempt to separate a lower boiling material (A)
from a higher boiling material (B). Spinning band distillation uses
a spinning band to force the rising vapors into close contact with
the descending condensate. This intimate contact between the two
phases produces a very good separation of the components.