Phosphate uptake by TiO2: Batch studies and NMR spectroscopic evidence for multisite adsorption

► Phosphate sorption on TiO2 was examined by batch experiments and NMR spectroscopy. ► The sorption of phosphate on TiO2 decreases with increasing pH. ► The phosphate sorption is rapid and mostly irreversible at pH 4.5 and 7.0. ► NMR indicates that the phosphate sorbed on TiO2 forms inner-sphere surface complexes.