Molecular Sieve Synthesis using Metallocenes as Structure Directing Agents

ABSTRACTWe have been exploring molecular sieve synthesis using metal complexes as templates. Our objectives were to affect the crystallization of new structures as well as prepare bifunctional catalysts via the encapsulation of metal complexes during synthesis. In this paper the results for the synthesis of SiO2, AlPO4 and SAPO molecular sieves in the presence of metallocenes will be presented. In particular, Cobalticinium ion, Cp2Co+, was found to be a template for Nonasil, AlPO4−5, AlPO4−16, SAPO−16 and CoAPO−16 which are known phases but require templates. The larger decamethyl derivative, CP*2Co+ has produced a novel high silica zeolite molecular sieve, UTD-1 as well as a new SAPO phase UTD-2 which appear to be large pore materials. In all cases, the metal complex is occluded intact and cannot be extracted. Aspects of the synthesis and characterization of these microporous materials are presented below.

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Synthesis and Characterization of GaPO4 Molecular Sieves Using Metal Complexes as Templates

MRS Proceedings ◽

10.1557/proc-454-217 ◽

1996 ◽

Vol 454 ◽

Cited By ~ 5

Author(s):

Kenneth J. Balkus ◽

Sung J. Kim ◽

Alan M. Sargeson

Keyword(s):

Metal Complex ◽

Metal Complexes ◽

Molecular Sieves ◽

Membered Ring ◽

Synthesis And Characterization ◽

Zeolite Synthesis ◽

The Novel ◽

Unknown Structure ◽

High Silica

ABSTRACTOur work on the preparation of zeolite ship-in-a-bottle complexes, which involves the encapsulation of metal complexes during zeolite synthesis, encouraged us to explore the relatively unknown structure directing properties of metal complexes. In particular, we have shown that bis(pentamethylcyclopentadienyl) cobalt(III) hydroxide, Cp*2CoOH was a template for the novel high silica zeolite UTD-1 which is the first zeolite having greater than a 12 membered ring pore structure. We have extended this strategy to other oxide compositions and metal complexes. In this paper we describe the preparation and characterization (XRD, SEM) of the gallophosphates Cloverite and UTD-10 using the metal complex [Co(NMe3)2sar]5+ (where (NMe3)2sar = 1,8-bis(trimethylammonio)-3,6,10,13,16,19-hexaazabicyclo[6.6.6]-icosane) as the template.

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Synthesis and characterization of large pore vanadium aluminosilicate beta molecular sieves

Zeolites ◽

10.1016/s0144-2449(97)00003-1 ◽

1997 ◽

Vol 18 (5-6) ◽

pp. 334-339 ◽

Cited By ~ 8

Author(s):

Hongbin Du ◽

Min Fang ◽

Yunling Liu ◽

Shilun Qiu ◽

Wenqin Pang

Keyword(s):

Molecular Sieves ◽

Synthesis And Characterization ◽

Large Pore

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Synthesis and Characterization of a New Aluminosilicate Molecular Sieve from Aluminosilica Perhydrate Hydrogel

Materials ◽

10.3390/ma13235469 ◽

2020 ◽

Vol 13 (23) ◽

pp. 5469

Author(s):

Haiqiang Ma ◽

Kun Jiao ◽

Xiangyu Xu ◽

Jiaqing Song

Keyword(s):

Molecular Sieves ◽

Molecular Sieve ◽

Critical Factor ◽

Synthesis And Characterization ◽

X Ray ◽

Cell Parameters ◽

Structure And Morphology ◽

Novel Structure ◽

Pure Phase

A novel structure aluminosilicate molecular sieve, named BUCT-3, was prepared by dynamic hydrothermal synthesis, and the critical factor to obtain the new structure is using an active silicon and aluminum source, aluminosilica perhydrate hydrogel. Meanwhile, only high content of O-O bonds can ensure the pure phase of BUCT-3. Through the characterization of x-ray powder diffraction (XRD), Fourier transform infrared spectra (FTIR), scanning electron microscopy (SEM), and so on, some structure and morphology information of BUCT-3 molecular sieves as well as the special silicon and aluminum source was obtained. It’s worth noticing that the O-O bonds of reactants can be reserved in the products, and thus, help us to get a new structure with cell parameters a = 8.9645 Å, b = 15.2727 Å, c = 11.3907 Å, α = 90°, β = 93.858°, γ = 90°. The crystal system is monoclinic. Though the thermostability of BUCT-3 is not satisfactory, its potential application derived from O-O bonds cannot be neglected.

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