Meso/macroporous AlPO-5 spherical macrostructures tailored by resin templating

A multi-step procedure for the preparation of meso/macroporous AlPO-5 spherical macrostructures using cation exchange resin beads as macrotemplates is presented. Firstly, aluminum species were introduced into the resin beads by ion exchange resulting in a resin-aluminum composite. Thereafter, the resin-aluminum composite was mixed with TEAOH, H3PO4 and distilled water and hydrothermally treated at 150 °C to yield resin-AlPO-5 composite. Finally, the resin was removed by calcination leaving behind self-bonded AlPO-5 spheres. The product AlPO-5 macrostructures were thoroughly characterized by SEM, XRD, nitrogen adsorption measurements, 31P and 27Al solid state NMR spectroscopy. The influence of various components of the synthesis mixture on the crystallinity, phase purity and stability of the AlPO-5 spheres was systematically studied. Samples prepared for different treatment times using the initial synthesis composition that gives spheres of the highest quality were used to study the crystallization process within the resin.