Abstract
The crystallization behavior of the initial mixture with the composition of Al2O3:4.0P2O5:3.0 diethylene-triamine(DETA):xHF:153H2O was investigated at 180 °C, where 0⩽x⩽3. If x⩽1.8, three-dimensional open-framework aluminophosphate AlPO-CJ31 was obtained. If 2⩽x⩽3, a chain-like aluminophosphate(1) was obtained. The crystallization process of both compounds was investigated by means of powder X-ray diffraction(XRD) and the concentrations of Al and P in the liquid product during the crystallization process were analysed by means of inductively coupled plasma atomic emission spectroscopy(ICP-AES). The evolution of the coordination state of Al, P and F during the crystallization was monitored with 27Al, 31P and 19F MAS NMR technique. The influence of the fluoride ions and the source of fluoride ions on the structure-directing effect of DETA was discussed. It was found that the fluoride ions changed the crystallization direction of the initial mixture, i.e., the structure-directing effect of DETA, via altering the distribution or micro-structure of the inorganic fragments.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
