Excess nonequilibrium collector adsorption and flotation rates

Experiments using an optically polished Pyrex disk and aqueous dodecylammon ium acetate (DAA) films showed that the velocity with which the films reced e increases markedly if the runs are repeated at short time intervals, wher e equilibrium cannot be reattained. This results from DAA molecules being d esorbed from the disappearing liquid-air interface and being deposited on t he solid-air interface being formed. Controlled experiments with Pyrex part icles in a modified Hallimond tube showed a similar increase in flotation r ate, again due to excess adsorption of DAA molecules that were transferred to the solid-air interface from the bubble on contact.