NCL-7, a novel all silica analog of polymorph B rich member of BEA family: synthesis and characterization
| Title | NCL-7, a novel all silica analog of polymorph B rich member of BEA family: synthesis and characterization |
| Publication Type | Journal Article |
| Year of Publication | 2007 |
| Authors | Kadgaonkar, MD, Kasture, MW, Bhange, DS, Joshi, PN, Ramaswamy, V, Kumar, R |
| Journal | Microporous and Mesoporous Materials |
| Volume | 101 |
| Issue | 1-2 |
| Pagination | 108-114 |
| Date Published | APR |
| Type of Article | Article |
| ISSN | 1520-6106 |
| Keywords | B-polymorph, DIFFaX, Promoter, Reitveld refinement, synthesis, zeolite beta |
| Abstract | {Polymorph B-rich BEA type structure, NCL-7, was synthesized using hydrothermal method in fluoride medium using perchloric acid as promoter. The samples were characterized using XRD, low temperature N-2-adsorption and Si-29 MASNMR. As the structure of beta is highly disordered Rietveld refinement of powder XRD patterns is precluded. Phase composition is derived using the simulated patterns for the random intergrowths of polymorph A and B by DIFFaX. The stacking direction c' is perpendicular to the a'b' plane of the layer. The composition of polymorph B is found to be ca. 60-65%. Two other structures namely NCL-5 and NCL-6 with varying degree of polymorph B enrichment were also synthesized. Synthesis parameters such as effect of H2O/SiO2, TEAOH/SiO2, HClO4/SiO2 and crystallization temperature were studied thoroughly. The present article explains for the first time the synthesis and characterization of NCL-7, an analog of BEA type family with enrichment of polymorph B and its comparison with normal beta (* |
| DOI | 10.1016/j.micromeso.2006.10.033 |
| Type of Journal (Indian or Foreign) | Foreign |
| Impact Factor (IF) | 3.349 |