ABSTRACT
This chapter limits to the less usual adsubble methods. It deals primarily with foam fractionation as representative of the foam separations, and bubble fractionation as representative of the nonfoaming separations. The adsubble methods comprise the various ways of separating dissolved or suspended material by means of adsorption or attachment at the surfaces of bubbles rising through the liquid. The most important subdivision is ore flotation or mineral flotation. After fine grinding, desirable mineral constituents are separated from undesirable constituents by selective attachment of one or the other to air bubbles which form an overflowing froth. Continuing with the classification, macroflotation is the removal of macroscopic particles, while microflotation refers to microscopic particles, especially microorganisms or colloids. In precipitate flotation a precipitate is removed by means of a collector which is other than the precipitating agent. However, this operation has been redefined more restrictively as precipitate flotation of the first kind.
