Blake, P.Ralston, J.2025-12-172025-12-171985Colloids and Surfaces, 1985; 16(1):41-530166-6622https://hdl.handle.net/1959.8/25848The flotation behaviour of methylated quartz particles of known surface coverage has been studied as a function of surface coverage and particle size over the range from 13 to 47 μm in diameter. The effects of ionic strength and water structure modifiers, particularly urea, have also been investigated. Certain experiments have been performed with methylated glass ballotini. For a given particle size, a critical surface coverage is required before flotation will occur. Current theory cannot describe this phenomenon nor the recovery versus surface coverage behaviour above the critical value. Ionic strength effects are interpreted in terms of double layer theory. At concentrations above ∼ 0.5 M, urea is shown to increase the rate of flotation of methylated glass ballotini, whilst similarly treated quartz particles remain unaffected. © 1985.enCopyright 1985 Elsevierfloatabilityflotation responsefroth flotation processparticle sizesurface coverageJournal article10.1016/0166-6622(85)80239-02-s2.0-0022146003