Selective depression of silicates in phosphate flotation using polyacrylamide-grafted nanoparticles.

In this study, novel in-house synthesized hybrid polyacrylamide-grafted nanoparticles (Hy-PAM) were used to enhance the recovery of phosphorus bearing minerals from plant tailing by the froth flotation process. Characterization assays, including X-ray diffraction (XRD) and mineral liberation analysis (MLA) indicated that apatite, fluorapatite and quartz are the major crystalline phases in the tailing sample. Flotation experiments were performed using a bench scale Denver flotation cell with 1 L capacity in the presence of sodium oleate, which was used as a collector. Several influencing parameters such as polymer dosage, pH, and the flotation time were investigated to optimize the flotation outcomes in terms of recovery and grade of phosphorus pentoxide (P 2 O 5 ). Results indicated that the P 2 O 5 content in the plant tailings can be enriched from 21.6% to 28.6% at a recovery value of 80.5% in the first 4 min of flotation without the need to add a pH modifier. Moreover, flotation kinetics was investigated using classical first order kinetic model which was evaluated based on the flotation rate constant, the ultimate phosphorous recovery and the correlation coefficients obtained by non-linear regression analysis. Results indicated that the ultimate recoveries and the flotation rate constant values were affected by the change of the pulp’s pH. [ABSTRACT FROM AUTHOR]