Correction to "Mechanism of Goethite Precipitation on Magnetite and Maghemite Nanoparticles Studied by Surface Complexation/Precipitation Modeling".

Abstract

Precipitation of goethite on magnetic nanoparticles (MNPs) has been proposed as an effective means to separate goethite from calcium sulfate in the iron removal process of zinc hydrometallurgy, which allows reuse of the hazardous residues. This study focuses on investigating the underlying mechanisms of goethite precipitation on magnetite and maghemite MNPs, providing insights on Fe(III)aq adsorption and nucleation of goethite on MNPs. A predictive surface complexation/precipitation model of the system was developed based on the results from two different types of experiments: the potentiometric titration of MNPs to calculate proton binding constants (Ka) of discrete MNP surface functional groups and the corresponding site concentrations; and adsorption of Fe(III)aq onto MNP surfaces to determine metal binding constants (Kf). The composition of the surface complexes on MNPs was determined by time-of-flight secondary ion mass spectrometry. The results indicated the formation of polynuclear surface complexe...