Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-23T03:30:25.319Z Has data issue: false hasContentIssue false

Reaction of Phosphate Compounds with a High-Silica Allophane

Published online by Cambridge University Press:  01 January 2024

Kiyoshi Okada*
Affiliation:
Department of Metallurgy and Ceramics Science, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro, Tokyo 152-8552, Japan
Koji Nishimuta
Affiliation:
Department of Metallurgy and Ceramics Science, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro, Tokyo 152-8552, Japan
Yoshikazu Kameshima
Affiliation:
Department of Metallurgy and Ceramics Science, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro, Tokyo 152-8552, Japan
Akira Nakajima
Affiliation:
Department of Metallurgy and Ceramics Science, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro, Tokyo 152-8552, Japan
Kenneth J. D. MacKenzie
Affiliation:
School of Chemical and Physical Sciences, Victoria University of Wellington, P.O. Box 600 Wellington, New Zealand
*
*E-mail address of corresponding author: [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The loading of various phosphates on the surfaces of nanoparticles of allophane (1–2SiO2·Al2O3·5–6H2O) was investigated. The allophane used was a high-silica type with a Si/Al ratio of 0.85. The phosphate-sorption isotherm was measured using (NH4)2HPO4 solution, which showed the highest phosphate sorption of the seven phosphates examined. This sorption isotherm was in better agreement with the Langmuir equation than the Freundlich equation. The resulting maximum sorption capacity was 4.87 mmol/g and the Langmuir constant was 0.0033 L/mmol. The sorption energy (ΔG) calculated from the Langmuir constant was −2.96 kJ/mol. The amount of loaded phosphate varied greatly according to the phosphate used, being greater for orthophosphates than for polyphosphates. The amount of loaded phosphate also depended on the cation present, in the order Ca-Na-NH4-phosphate. The Si/Al ratios of the samples were decreased by orthophosphate loading due to the partial replacement of SiO4 by PO4 tetrahedra, but this effect was offset by the partial dissolution of the allophane by polyphosphate loading. The 29Si magic angle spinning nuclear magnetic resonance (MAS NMR) spectra of all the phosphateloaded samples showed an increase of a peak at −90 ppm (the Q1Q3 polymerized tetrahedral unit) and the decrease of a peak at −78 ppm peak (the Qo monomeric tetrahedral unit). The 31P MAS NMR spectra showed peaks at ~−10 ppm, assigned to Q2 units corresponding to polymerized tetrahedra which consisted of loaded PO4 together with Si(Al)O4. The structure changes produced in allophane by phosphate loading are discussed in light of these data.

Type
Research Article
Copyright
Copyright © The Clay Minerals Society 2005

References

Clark, C.J. and McBride, M.B., (1985) Adsorption of Cu(II) by allophane as affected by phosphate Soil Science 139 412421 10.1097/00010694-198505000-00006.CrossRefGoogle Scholar
Elhadi, E.A. Matsue, N. and Henmi, T., (2000) Effect of molybdate adsorption on some surface properties of nanoball allophane Clay Science 11 405416.Google Scholar
Hayashi, S. and Hayamizu, K., (1989) High-resolution solidstate 31P NMR of alkali phosphates Bulletin of the Chemical Society of Japan 62 30613068 10.1246/bcsj.62.3061.CrossRefGoogle Scholar
Johan, E. Matsue, N. and Henmi, T., (1997) Phosphate adsorption on nano-ball allophane and its molecular orbital analysis Clay Science 10 259270.Google Scholar
Kitagawa, Y., (1971) The ‘unit particle’ of allophane American Mineralogist 56 465475.Google Scholar
Lindner, G.-G. Nakazawa, H. and Hayashi, S., (1998) Hollow nanospheres, allophanes ‘All-organic’ synthesis and characterization Microporous and Mesoporous Materials 21 381386 10.1016/S1387-1811(98)00002-X.CrossRefGoogle Scholar
MacKenzie, K.J.D. and Smith, M.E. (2002) Multinuclear Solid-State NMR of Inorganic Materials. Pergamon Materials Series, vol. 6, Pergamon, Oxford, UK.CrossRefGoogle Scholar
MacKenzie, K.J.D. Bowden, M.E. and Meinhold, R.H., (1991) The structure and thermal transformations of allophanes studied by 29Si and 27Al high resolution solid-state NMR Clays and Clay Minerals 39 337346 10.1346/CCMN.1991.0390401.CrossRefGoogle Scholar
Naeem, A. Mustafa, S. Rehana, N. Dilara, B. and Murtaza, S., (2002) The sorption of divalent metal ions on AlPO4 Journal of Colloid and Interface Science 252 614 10.1006/jcis.2002.8425.CrossRefGoogle ScholarPubMed
Nanzyo, M., (1987) Formation of noncrystalline aluminum phosphate through phosphate sorption on allophanic Ando soils Communications of Soil Science and Plant Analysis 18 735742 10.1080/00103628709367857.CrossRefGoogle Scholar
Nanzyo, M., (1995) Reactions of phosphate with soil colloids Nendo-Kagaku 35 108119.Google Scholar
Nartey, E. Matsue, N. and Henmi, T., (2001) Charge characteristics modification mechanisms of nano-ball allophane upon orthosilicic acid adsorption Clay Science 11 465477.Google Scholar
Okada, K. Morikawa, H. Iwai, S. Ohira, Y. and Ossaka, J., (1975) A structure model of allophane Clay Science 4 291303.Google Scholar
Padilla, G.N. Matsue, N. and Henmi, T., (2002) Change in surface charge properties of nano-ball allophane as influenced by sulfate adsorption Clay Science 12 3339.Google Scholar
Padilla, G.N. Matsue, N. and Henmi, T., (2002) Adsorption of sulfate and nitrate on nano-ball allophane Clay Science 11 575584.Google Scholar
Parfitt, R.L. Furkert, R.J. and Henmi, T., (1980) Identification and structure of two types of allophane from volcanic ash soils and tephra Clays and Clay Minerals 28 328334 10.1346/CCMN.1980.0280502.CrossRefGoogle Scholar
Rajan, S.S.S., (1975) Mechanism of phosphate adsorption by allophane clays New Zealand Journal of Science 18 93101.Google Scholar
Smith, J.P. and Brown, W.E., (1959) X-ray studies of aluminum and iron phosphates containing potassium or ammonium American Mineralogist 44 138142.Google Scholar
Son, L.T. Matsue, N. and Henmi, T., (1998) Boron adsorption on allophane with nano-ball morphology Clay Science 10 315325.Google Scholar
Stumm, W. and Morgan, J.J., (1996) Aquatic Chemistry 3rd edition Chichester, UK John Wiley & Sons.Google Scholar
Tarasevich, Y.u.I. and Klimova, G.M., (2001) Complex-forming adsorbents based on kaolinite, aluminium oxide and phosphates for the extraction and concentration of heavy metal ions from water solutions Applied Clay Science 19 95101 10.1016/S0169-1317(01)00061-8.CrossRefGoogle Scholar
Wada, K., (1959) Reaction of phosphate with allophane and halloysite Soil Science 87 325330 10.1097/00010694-195905000-00023.CrossRefGoogle Scholar
Wada, K. (1979) Structural Formulas of Allophanes Proceedings of the 6th International Clay Conference, Oxford, 1978 (Mortland, M.M. and Farmer, V.C., editors). Amsterdam Elsevier pp. 537553.Google Scholar