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2019_EJRNL_PP_Nicholas_Allen_-1.pdf
Terbatas Irwan Sofiyan
» ITB

The adsorption of aqueous ions onto natural mineral surfaces controls numerous mineral?water interactions and is governed by, among other numerous factors, ion dehydration and hydrolysis. This work explored the extent to which dehydration and hydrolysis affect the adsorption of three metal cations, Al3+, Cr3+, and Mn2+, onto quartz (SiO2) and corundum (Al2O3) surfaces at pH 3.8 through the integration of flow microcalorimetry (FMC), quartz crystal microbalance with dissipation (QCM-D) measurements and density functional theory (DFT) calculations. At pH 3.8, negligible amounts of Mn2+ and Al3+ are hydrolyzed, while 78% of Cr3+ exist in hydrolyzed species. QCM-D and FMC measurements showed that Al3+ and Cr3+ adsorb to both surfaces, while Mn2+ adsorbed only to Al2O3. DFT bond energy calculations confirmed the favorable bonding between .....