27Al NMR STUDY OF THE EFFECT OF AQUEOUS AND METHANOLIC MEDIA ON DISTRIBUTION OF TETRAPHENYLAMMONIUM ALUMINOSILICATE SPECIES

27Al NMR spectroscopy tetraphenylammonium hydroxide evolution with time methanolic aluminosilicate solutions.

CRYSTAL STRUCTURE OF AN END-ON AZIDO-BRIDGED POLYMERIC ZINC(II) COMPLEX, ВЛИЯНИЕ ПОЛЯРНОСТИ ОРГАНИЧЕСКОГО РАСТВОРИТЕЛЯ НА СТРУКТУРУ АДСОРБЦИОННОГО СЛОЯ НАНОЧАСТИЦ ЗОЛОТА ПО ДАННЫМ ФОТОН-КОРРЕЛЯЦИОННОЙ СПЕКТРОСКОПИИ, ...

2015. 56, 2 - – - . 266 – 274 UDC 541.67:546.621:546.21 27Al NMR STUDY OF THE EFFECT OF AQUEOUS AND METHANOLIC MEDIA ON DISTRIBUTION OF TETRAPHENYLAMMONIUM ALUMINOSILICATE SPECIES N. Goudarzi Faculty of Chemistry, Shahrood University of Technology, P. O. Box 316, Shahrood, Iran E-mail: goudarzi@shahroodut.ac.ir, goudarzi10@gmail.com Received August, 27, 2013 The effects of tetraphenylammonium (TPhA) on the equilibrium distribution of aluminosilicate oligomers in aqueous and methanolic alkaline aluminosilicate solutions were investigated using 27Al NMR spectroscopy. <...> Alkaline solutions containing both silicate and aluminate ions are of considerable research interest inter alia because of their involvement in the synthesis of zeolites. <...> In the present work, we use 27Al NMR to characterize alkaline aqueous and methanolic tetraphenylammonium (TPhA) aluminosilicate solutions with different Al/Si ratios. <...> Tetraphenylammonium (TPhA) used as a cation template and no alkaline metals are used for preparation of aluminosilicate solutions. <...> The distribution of aluminosilicate species was affected by the presence of the alcohol such as methanol and the method of mixing the silicate and aluminosilicate solutions. <...> To understand the reaction between silicate and aluminate ions in this system, the evolutions of 27Al NMR spectra with time are investigated. <...> Keywords: 27Al NMR spectroscopy, tetraphenylammonium hydroxide, evolution with time, methanolic aluminosilicate solutions. <...> Kinrade and Swaddle identified 29Si-NMR peaks due to low molecular weight aluminosilicate anions of sodium aluminate solutions by 29Si NMR spectroscopy [ 18 ]. <...> They also reported the correlation between the partial charge on Si atoms and chemical shift was used to confirm the assignment of 29SiNMR peaks due to cage species containing double-rings, such as prismatic hexamer and cubic octamer, with some replacement by aluminum [ 28 ]. Goudarzi N., 2015 -. 2015. . 56, 2 267 scopies [ 29—35 ]. <...> The notation Qn for silicate solutions, where n refers to the number of siloxane bridges, is well established [10—15 ]. <...> Thus, if aluminum has no silioxane bridges, as for the aluminate anion AlO5 Evidence of dissolved aluminosilicate anions has come from both 29Si and 27Al NMR spectro4 (or its protonated congeners up to Al(OH) ), it is represented as q0, where q1, q2, q3 and q4 indicate Al(1OSi), Al <...>

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