TY - JOUR
T1 - Size-dependent sorption of myo-inositol hexakisphosphate and orthophosphate on nano-¿-Al2O3
AU - Yan, Y.
AU - Koopal, L.K.
AU - Li, W.
AU - Zheng, A.
AU - Yang, J.
AU - Liu, F.
AU - Feng, X.
PY - 2015
Y1 - 2015
N2 - The effects of particle size (5, 35 and 70 nm) on the sorption of myo-inositol hexakisphosphate (IHP) and inorganic phosphate (KH2PO4, Pi) on ¿-Al2O3 nanoparticles were investigated using batch sorption experiments, zeta potential measurements and solid-state nuclear magnetic resonance spectroscopy (NMR). The results show that the maximum sorption densities (µmol m-2) for IHP and Pi increase with decreasing ¿-Al2O3 particle size. The sorption affinity of ¿-Al2O3 for IHP and Pi generally increases with decreasing particle size, and the sorption affinity for IHP is approximately one order of magnitude greater than that for Pi. In our experimental time scale, surface complexation is the main mechanism for IHP and Pi sorption on large size ¿-Al2O3. While an additional surface precipitation mechanism, indicated by solid-state 31P and 27Al NMR data, is partly responsible for the greater sorption density on very small size ¿-Al2O3. Compared with Pi, the effect of particle size on the sorption of IHP is more pronounced. The results suggest a size-dependent surface reactivity of Al2O3 nanoparticles with Pi/IHP. The underlying mechanism will also be relevant for other small nanosize (hydr)oxide particles and is important for our understanding of the role of small nanoparticles in controlling the mobility and fate of organic and inorganic phosphates in the environment.
AB - The effects of particle size (5, 35 and 70 nm) on the sorption of myo-inositol hexakisphosphate (IHP) and inorganic phosphate (KH2PO4, Pi) on ¿-Al2O3 nanoparticles were investigated using batch sorption experiments, zeta potential measurements and solid-state nuclear magnetic resonance spectroscopy (NMR). The results show that the maximum sorption densities (µmol m-2) for IHP and Pi increase with decreasing ¿-Al2O3 particle size. The sorption affinity of ¿-Al2O3 for IHP and Pi generally increases with decreasing particle size, and the sorption affinity for IHP is approximately one order of magnitude greater than that for Pi. In our experimental time scale, surface complexation is the main mechanism for IHP and Pi sorption on large size ¿-Al2O3. While an additional surface precipitation mechanism, indicated by solid-state 31P and 27Al NMR data, is partly responsible for the greater sorption density on very small size ¿-Al2O3. Compared with Pi, the effect of particle size on the sorption of IHP is more pronounced. The results suggest a size-dependent surface reactivity of Al2O3 nanoparticles with Pi/IHP. The underlying mechanism will also be relevant for other small nanosize (hydr)oxide particles and is important for our understanding of the role of small nanoparticles in controlling the mobility and fate of organic and inorganic phosphates in the environment.
KW - Myo-Inositol hexakisphosphate
KW - Nano-γ-Al2O3
KW - Orthophosphate
KW - Particle size
KW - Sorption
KW - Surface precipitation
U2 - 10.1016/j.jcis.2015.03.045
DO - 10.1016/j.jcis.2015.03.045
M3 - Article
SN - 0021-9797
VL - 451
SP - 85
EP - 92
JO - Journal of Colloid and Interface Science
JF - Journal of Colloid and Interface Science
ER -