Reinforced SIL-1 micromembranes integrated on chip: APPLICATION to CO2 separation

A novel 4-step microfabrication process is proposed in this work to prepare arrays of c-oriented silicalite (SIL-1) micromembranes on customized silicon nitride (Si3Nx) microsieves. The arrays are integrated on chip and their overall porosity values can be tuned from 1.6% to 19.9%. A low stress Si3N...

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Detalles Bibliográficos
Autores: Pellejero, Ismael, Urbiztondo, Miguel A., Pina, María Pilar, Santamaría, Jesús
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2014
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/369003
Acceso en línea:http://hdl.handle.net/10261/369003
Access Level:acceso abierto
Palabra clave:Silicon nitride microsieves
Silicalite micromembranes
Adsorption affinity
Carbon dioxide separation
Residual stress
Descripción
Sumario:A novel 4-step microfabrication process is proposed in this work to prepare arrays of c-oriented silicalite (SIL-1) micromembranes on customized silicon nitride (Si3Nx) microsieves. The arrays are integrated on chip and their overall porosity values can be tuned from 1.6% to 19.9%. A low stress Si3Nx microfabricated sieve has been used as support to reinforce via mechanical interlocking and to reduce the effects of the residual stress during membrane processing. The secondary hydrothermal growth over the Si3Nx microsieves also changes the SIL-1 chemistry, improving its affinity towards CO2 adsorption. As a result, the SIL-1/Si3Nx micromembranes integrated on chip facilitate the preferential permeation of CO2 in CO2/H2 mixtures, showing a maximum CO2/H2 separation factor of 16.9 and a CO2 permeance of 8.2×10−7 mol m−2 s−1 Pa−1 at ambient conditions.