TY - JOUR

T1 - Solution mechanisms of phosphorus in quenched hydrous and anhydrous granitic glass as a function of peraluminosity

AU - Mysen, B. O.

AU - Holtz, Francois

AU - Pichavant, Michel

AU - Beny, Jean M.

AU - Montel, J. M.

N1 - Funding Information: Acknowledgments--A majority of this work was conducted while one of us (BOM) visited CNRS-CRSCM during the summer of 1994. The hospitality extended by CNRS is greatly appreciated. This work was partially supported by NSF grants EAR9218890 and EAR9614423 to BOM, by a grant from Centre National de la Re-cherce Scientifique through its Programme International de Cooperation Scientifique (PICS 192) and partially by the NSF-sponsored Center for High-Pressure Research (CHiPR). Critical reviews by M. Toplis, D. London, G. Morgan, and F. R. Ryerson improved the manuscript. Copyright: Copyright 2017 Elsevier B.V., All rights reserved.

PY - 1997/9

Y1 - 1997/9

N2 - Solution mechanisms of P in metaluminous to peraluminous quenched, hydrous (∼9 wt% H2O) and anhydrous glasses in the system CaO-Na2O-K2O-Al2O3-SiO 2-P2O5 have been examined with microRaman spectroscopy. The principal aim was to examine relative stability of phosphate complexes as a function of bulk chemical composition. Increasing peraluminosity was accomplished by increasing Al3+ and Ca2+ proportions with constant SiO2 content. The molar ratio Al2O3/(CaO + Na2O + K2O)(A/ CNK) ranged from 1 (metaluminous) to ∼1.3 (peraluminous). In all compositions P5+ is bonded to Al3+ to form AlPO4 complexes. The principal solution mechanism is one where depolymerized species (Q3), involving Al3+ both within and outside the aluminosilicate network, interact with P to form the AlPO4 complex together with Q4 species. The mechanism does not involve alkali metals or alkaline earths. In anhydrous compositions, the spectra are interpreted to suggest Si-O-P cross-linking in the structure. In hydrous compositions, evidence for Si-O-P bonding is less evident. In such glasses, there is, however, possible spectroscopic evidence for Si-OH bonding and possibly P-OH bonding resulting from breakage of cross-linking Si-O-P bonds existing in the anhydrous glasses. Therefore, the water content of peraluminous aluminosilicate melts is likely to affect the solubility behavior of P, and conversely, the solubility behavior of H2O is affected by P in such melts.

AB - Solution mechanisms of P in metaluminous to peraluminous quenched, hydrous (∼9 wt% H2O) and anhydrous glasses in the system CaO-Na2O-K2O-Al2O3-SiO 2-P2O5 have been examined with microRaman spectroscopy. The principal aim was to examine relative stability of phosphate complexes as a function of bulk chemical composition. Increasing peraluminosity was accomplished by increasing Al3+ and Ca2+ proportions with constant SiO2 content. The molar ratio Al2O3/(CaO + Na2O + K2O)(A/ CNK) ranged from 1 (metaluminous) to ∼1.3 (peraluminous). In all compositions P5+ is bonded to Al3+ to form AlPO4 complexes. The principal solution mechanism is one where depolymerized species (Q3), involving Al3+ both within and outside the aluminosilicate network, interact with P to form the AlPO4 complex together with Q4 species. The mechanism does not involve alkali metals or alkaline earths. In anhydrous compositions, the spectra are interpreted to suggest Si-O-P cross-linking in the structure. In hydrous compositions, evidence for Si-O-P bonding is less evident. In such glasses, there is, however, possible spectroscopic evidence for Si-OH bonding and possibly P-OH bonding resulting from breakage of cross-linking Si-O-P bonds existing in the anhydrous glasses. Therefore, the water content of peraluminous aluminosilicate melts is likely to affect the solubility behavior of P, and conversely, the solubility behavior of H2O is affected by P in such melts.

UR - http://www.scopus.com/inward/record.url?scp=0031417072&partnerID=8YFLogxK

U2 - 10.1016/S0016-7037(97)00193-2

DO - 10.1016/S0016-7037(97)00193-2

M3 - Article

AN - SCOPUS:0031417072

VL - 61

SP - 3913

EP - 3926

JO - Geochimica et Cosmochimica Acta

JF - Geochimica et Cosmochimica Acta

SN - 0016-7037

IS - 18

ER -