Cellulose-mineral interactions based on the DLVO theory and their correlation with flotability

Nowadays, humankind undergoes intensive efforts to minimize the environmental pollution worldwide. One main challenge is the reduction of chemicals based on mineral oil and petroleum by the employment of sustainable and environment-friendly alternatives. A promising candidate is cellulose, which is a green, sustainable and abundant polymer. Cellulose can be treated physically and chemically to obtain tailored properties, which enable the employment of cellulose in industrial processes, such as flotation. Nonetheless, the structure of cellulose, which differs substantially from conventional flotation reagents, leads to different behaviour in ore dressing and in subsequent particle-bubble attachment. Therefore, the interactions between cellulose and the minerals under different conditions is investigated using the Derjaguin-Landau, Verwey-Overbeek (DLVO) theory, comprising van-der-Waals and electrostatic interactions, and the results are put in context with flotation recoveries using a single gas capillary Hallimond tube. The results obtained indicate that van-der-Waals interactions are dominant at very close distances and electrostatic interactions at distances of several nanometres between cellulose and the minerals. Accordingly, this study illuminates that the occurrence of physisorption phenomena between cellulose and the minerals and efficient particle-bubble attachment depend on electrostatic interactions between them.