Interfacial properties of natural magnetite particles compared with their synthetic analogue

Abstract

a b s t r a c tUnderstanding of the interactions between iron oxides and flotation reagents is important both for flotation and agglomeration of iron ore. Model systems comprising synthetic iron oxides and pure chemical reagents are commonly applied in experimental work in order to obtain high quality data and to ease the interpretation of the empirical data. Whether the results obtained using model systems are valid for iron ore minerals and commercial reagents is a question seldom addressed in the literature. It is shown in this work that previously reported results obtained from a model system, concerning adsorption of a carboxylate surfactant and sodium metasilicate onto synthetic magnetite nanoparticles, as obtained by in situ ATR-FTIR spectroscopy and contact angle measurements, are applicable to adsorption of flotation reagents on magnetite concentrate. Additionally, the problem of restoring magnetite wetting after flotation is addressed since good wetting of a magnetite concentrate is required to produce iron ore pellets by wet agglomeration. The results from the present work indicate that the wettability of both synthetic magnetite coated with surfactant and magnetite concentrate after flotation can be improved by adsorbing a hydrophilizing agent such as silicate or polyacrylate.

Surface Forces between Nanomagnetite and Silica in Aqueous Ca2+ Solutions Studied with AFM Colloidal Probe Method

“…Iron oxide nanoparticles have attracted significant research interest due to their superparamagnetic properties [8] and high potential to be used in biomedicine [6]. Synthetic nanomagnetite (Fe 3 O 4 ) particles with spherical shapes and known chemical composition can also be used to model natural magnetite when natural particles cannot be used due to their larger size (smaller surface area per gram) and complex chemical composition [4,5,9]. Interaction between natural magnetite and soluble silicate is of importance for mineral processing in processes such as flotation, dispersion, and agglomeration of iron ore concentrate.…”

“…Interaction between natural magnetite and soluble silicate is of importance for mineral processing in processes such as flotation, dispersion, and agglomeration of iron ore concentrate. It is known that silicate anions adsorb onto magnetite even at alkaline solution (7 < pH < 9), although the magnetite surface is negatively charged, indicating a condensation reaction between silicate and magnetite [9,10]. A similar condensation reaction might also appear between magnetite and silica (SiO 2 ) particles.…”

Measurement for Contact Angle of Iron Ore Particles and Water

“…100) Magnetite pellet concentrate after flotation and magnetic separation from the pelletizing plant in Kiruna, Sweden was provided by LKAB and was dried in an oven at 50°C before test. 92) In the experiment of Iveson, ore compositions were determined using a manual point counting technique on a polished surface of each ore. 48) Both Iveson and Huang obtained the true density of samples by volumetric displacement of cyclohexane in a 25 ml flask. [48][49][50] S BET is the specific surface area represents the specific area of the internal and external surfaces was measured by nitrogen adsorption method.…”

“…In the study of Potapoya, 92) for the natural magnetite particles, the contact angle was estimated to be 50-60°. Compared with the value of contact angle for synthetic magnetite nanoparticles, they found that contact angles of natural magnetite particles measured by the Washburn method is normally reported to be higher, which may be partly due to the measuring technique and physical properties of natural particles.…”

Enhancing flotation of smithsonite by using 1,3,5-Triazinane-2,4,6-trithione as sulfidation

“…The hydrophobicity of mineral particles surface could be indirectly indicated by the change in the contact angle before and after treatment (Potapova et al, 2012). Fig.…”