TY - JOUR

T1 - Synthesis and properties of phosphate cancrinite (PO4-CAN) a synthetic counterpart of depmeierite

AU - Buhl, J. Ch

AU - Petrov, V.

N1 - Funding Information: The authors gratefully acknowledge Dr. M. Fechtelkord from Ruhr-Universität Bochum for performing the 31P MAS NMR measurement. Open access funding enabled and organized by Projekt DEAL.

PY - 2021/9/2

Y1 - 2021/9/2

N2 - Phosphate cancrinite (PO4-CAN) has been synthesized under mild hydrothermal conditions at 473 K using kaolin, sodium orthophosphate-dodecahydrate and strong alkaline conditions (8 M NaOH solution). Cancrinite crystals of rod-like habit and maximum lengths up to 2 μm were observed and characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDXS) and Fourier transform infrared spectroscopy (FTIR). Magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR) of the nucleus 31P, thermogravimetry (TG/DTG) and heating experiments under open conditions in a furnace were additionally performed. The empirical formula Na8[SiAlO4]6(PO4)0.58(CO3)0.13(H2O)4.6 was calculated from EDXS analyses and TG data under consideration of a minor carbonate content, detected by FTIR spectroscopy. PO4-CAN is stable up to 800 °C before thermal destruction rapidly occurs at 825 °C. The final product of TG analyses at 1000 °C is a mixture of a nepheline-like phase and the phosphate content of the initial cancrinite sample. XRD and FTIR results of the synthesis product are in good agreement with literature data of the rare mineral depmeierite.

AB - Phosphate cancrinite (PO4-CAN) has been synthesized under mild hydrothermal conditions at 473 K using kaolin, sodium orthophosphate-dodecahydrate and strong alkaline conditions (8 M NaOH solution). Cancrinite crystals of rod-like habit and maximum lengths up to 2 μm were observed and characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDXS) and Fourier transform infrared spectroscopy (FTIR). Magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR) of the nucleus 31P, thermogravimetry (TG/DTG) and heating experiments under open conditions in a furnace were additionally performed. The empirical formula Na8[SiAlO4]6(PO4)0.58(CO3)0.13(H2O)4.6 was calculated from EDXS analyses and TG data under consideration of a minor carbonate content, detected by FTIR spectroscopy. PO4-CAN is stable up to 800 °C before thermal destruction rapidly occurs at 825 °C. The final product of TG analyses at 1000 °C is a mixture of a nepheline-like phase and the phosphate content of the initial cancrinite sample. XRD and FTIR results of the synthesis product are in good agreement with literature data of the rare mineral depmeierite.

KW - P MAS NMR

KW - framework type CAN

KW - hydrothermal synthesis

KW - microporous solids

KW - phosphate enclathrated zeolites

UR - http://www.scopus.com/inward/record.url?scp=85111571248&partnerID=8YFLogxK

U2 - 10.1002/zaac.202100160

DO - 10.1002/zaac.202100160

M3 - Article

AN - SCOPUS:85111571248

VL - 647

SP - 1647

EP - 1654

JO - Zeitschrift fur Anorganische und Allgemeine Chemie

JF - Zeitschrift fur Anorganische und Allgemeine Chemie

SN - 0044-2313

IS - 16-17

ER -