Separation of plastic particles by froth flotation
The quantity of plastic waste is rising every year which calls for the development of appropriate technology for proper management. Froth flotation of plastics is one of the promising methods for separating plastics and solving one of the major problems in recycling. Nonetheless, this method suffers from a shortage of knowledge in surface chemistry.
The formation of bubble nuclei at the surface of plastics can change the surface characteristic by increasing the particle contact angle, attachment force, and particles aggregation, minimizing surface coating by the use of depressant/reagent consumption. In this regard, understanding the behavior of air bubbles after adding reagents is an important subject in the flotation process of polymer separation since the larger bubbles can increase the efficiency of the flotation system.
In this project, aspects of the flotation of micro- and mesoscopic particles are explored. One focus is on understanding the promotion of formation of microbubbles at the surface of the plastic particle by surfactants. In addition, the growth behavior of bubble nuclei at the surface of plastic particles, contact angle changes and their relationship to surface roughness has been considered. To further enhance our study, we have described the surface property of the plastic particle and that is quantified with a new method representing detailed topographical data of the surface.
Mitra Nikpay, Akira Otsuki, Frans Munnik, Kerstin Eckert (2017), Separation of plastic particles by froth flotation: effect of surfactant in bubble nuclei growth, in preparation for J. Waste Managment