Health & Environmental Research Online (HERO)


Print Feedback Export to File
8466748 
Journal Article 
Application of phosphorus-31 and aluminum-27 NMR spectroscopic techniques to study aqueous and methanolic solutions of tetraphenylammonium aluminophosphate 
Goudarzi, N; Amin, AH; , 
2017 
Yes 
Journal of Molecular Structure
ISSN: 0022-2860
EISSN: 1872-8014 
ELSEVIER SCIENCE BV 
AMSTERDAM 
1128 
338-344 
English 
WOS:000387194600042 
In this work, aluminum-27 and phosphorus-31 NMR spectroscopic techniques were used to investigate and characterize the distribution of aluminophosphate (AIPO) species soluble in the aqueous and methanolic solutions of tetraphenylammonium (TPhA) chloride. The reaction between hexaaquaaluminum cations, [A1(H2O)(6)](3+), and different phosphate ligands such as H3PO4, H2PO4-, and the acidic dimers H6P2O8 and H5P2O8- resulted in the formation of the soluble AIPO cations. The effective aluminum-27 and phosphorous-31 NMR spectroscopies can be employed to characterize the species present in a solution. Assignment of the peaks present in the aluminum-27 NMR spectra to the aluminate species or aluminate connectivities was done to acquire information about different AIPO complexes. Some resonance lines were observed in the phosphorus-31 {1H} NMR spectra, indicating the existence of different complexes in the AIPO solutions. Some peaks were observed in the methanolic solutions of AIPO at the chemical shifts of-0.41,-6.4,-7.5,-7.9,-13.1,-13.9,-16.6,-18.1, and-20.6 ppm. Four additional peaks were also observed in the phosphorus-31 (1H) NMR spectra of the methanolic solutions of AIPO, whose intensities changed with changes in the methanol:water volume ratio; they were observed in methanol but not in aqueous AIPO. (C) 2016 Elsevier B.V. All rights reserved. 
27Al NMR spectroscopy; Aluminophosphate (AlPO) species; Methanolic solutions of AlPO species; Phosphorus-31 NMR spectroscopy; Tetraphenylammonium (TPhA)