A Technique to Study the Adsorption of Oily Collectors onto Coal and Gangue Minerals

Abstract

A technique has been developed to study the adsorption of paraffinic i.e. alkane (or other hydrocarbon oil) collectors onto coal and gangue mineral surfaces under dynamic conditions. The oily collector is present as the dispersed phase of a dilute oil-in-water dispersion. Solid particles are added to this dispersion and agitated to give a system analagous to that found in flotation cells prior to aeration, i.e. during conditioning. The technique enables study of the overall or apparent kinetics involved in the collision and effective adsorption of collector droplets onto coal or mineral particles. Results obtained show that adsorption is very rapid and tenacious, even under turbulent conditions. The hydrocarbon collectors are selective. Adsorption onto gangue (undesirable minerals) is limited and decreasing adsorption is evident as coal fractions become increasingly dense, i.e. as their gangue (ash) content increases. Commercial kerosene (Shellsol K) behaved in a similar way to the pure alkane collector with similar boiling point (dodecane).