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Kinetics and Mechanism of the Hydrolysis and Rearrangement Processes within the Assembly–Disassembly–Organization–Reassembly Synthesis of Zeolites

[Image: see text] The hydrolysis (disassembly, D) and rearrangement (organization, O) steps of the assembly–disassembly–organization–reassembly (ADOR) process for the synthesis of zeolites have been studied. Germanium-rich UTL was subjected to hydrolysis conditions in water to understand the effects...

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Detalles Bibliográficos
Autores principales: Henkelis, Susan E., Mazur, Michal, Rice, Cameron M., Wheatley, Paul S., Ashbrook, Sharon E., Morris, Russell E.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2019
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6515985/
https://www.ncbi.nlm.nih.gov/pubmed/30786710
http://dx.doi.org/10.1021/jacs.9b00643
Descripción
Sumario:[Image: see text] The hydrolysis (disassembly, D) and rearrangement (organization, O) steps of the assembly–disassembly–organization–reassembly (ADOR) process for the synthesis of zeolites have been studied. Germanium-rich UTL was subjected to hydrolysis conditions in water to understand the effects of temperature (100, 92, 85, 81, 77, and 70 °C). Samples were taken periodically over an 8–37 h period, and each sample was analyzed by powder X-ray diffraction. The results show that the hydrolysis step is solely dependent on the presence of liquid water, whereas the rearrangement is dependent on the temperature of the system. The kinetics have been investigated using the Avrami–Erofeev model. With increasing temperature, an increase in the rate of reaction for the rearrangement step was observed, and the Arrhenius equation was used to ascertain an apparent activation energy for the rearrangement from the kinetic product of the disassembly (IPC-1P) to the thermodynamic product of the rearrangement (IPC-2P). From this information, a mechanism for this transformation can be postulated.