abstract
A zeolite phillipsite (PHI) analogue with low silica contents has been synthesized from a NH(4)F-Al(2)O(3)-SiO(2)-piperazine-H(2)O system. The obtained zeolite PHI analogue grows as agglomerates of intergrown submicron-sized crystals. The synthesis process in fluoride-based media has been investigated. It has been unequivocally demonstrated that no zeolite phase occurred in the absence of piperazine or NH(4)F. The results of CHN elemental analyses as well as of TG analyses confirmed that both piperazine and NH(4)(+) had been incorporated into the zeolitic structure. Thus, the zeolite PHI analogue is seemingly derived from the cooperative structure-directing effect of the organic molecule piperazine and the inorganic cation NH(4)(+). The use of a suitable combination of inorganic cation and organic molecule in fluoride-based media may provide an effective means of exploring new frameworks with low Si/Al ratios. (C) 2009 Elsevier Inc. All rights reserved.
keywords
POWDER DIFFRACTION; CRYSTAL STRUCTURE; HARMOTOME; SYSTEM
subject category
Chemistry; Science & Technology - Other Topics; Materials Science
authors
Shi, Q; Xu, H; Li, JP; Lin, Z; Dong, JX
our authors
Zhi Lin
Principal Researcheracknowledgements
The authors are thankful for the Natural Science Foundation of China (20373047) for financial support. Z.L. acknowledges the funding from FCT, POCI2010 and FEDER.