It was also free of the contamination that occurs through
material settling on the sides of the funnel. Moreover, it proved to
work much better than the centrifuging method since even after 20 min of centrifuging it was observed that it was not possible to produce a distinct separation line between the floats/sinks products at fine sizes.
Discharging the products from the centrifuge tubes was also a very time consuming and inefficient process.
Similar difficulties in using centrifuging were also reported by Dyrkacz and Ruscic (1992).