A New Concept for the Fabrication of Hydrogen Selective Silica Membranes

Michael Tsapatsis

关键词: CARBON DIOXIDE;    FABRICATION;    HYDROGEN;    MATRICES;    MEMBRANES;    MIXTURES;    MOLECULAR SIEVES;    NITROGEN;    SILICA;    SURFACE COATING;    SYNTHESIS;    ZEOLITES;   

DOI  :  10.2172/945017
RP-ID  :  None
PID  :  OSTI ID: 945017
Others  :  TRN: US200903%%56

学科分类：再生能源与代替技术

美国|英语

来源: SciTech Connect

【 摘 要 】

It was proposed to investigate a new concept for the synthesis of molecular sieve hydrogen selective membranes. This concept is based on the use of exfoliated layered zeolite precursors in coating processes to make nanocomposite films with inorganic or polymeric matrices. We discovered that creating exfoliated zeolite layers was much more difficult than anticipated because the methods originally proposed (based on existing literature reports) were not successful in providing exfoliated layers while preserving their porous structure. Although the original goals of fabricating high-selectivity-high-flux membranes that are stable under conditions present in a water-gas-shift reactor and that are able to selectively permeate hydrogen over all other components of the mixtures present in these reactors were not accomplished fully, significant progress has been made as follows: (1) Proof-of-concept hydrogen-selective nanocomposite membranes have been fabricated; (2) Methods to exfoliate layered zeolite precursors preserving the layer structure were identified; and (3) Unexpectedly, membranes exhibiting high ideal selectivity for carbon dioxide over nitrogen at room temperature were produced. The findings listed above provide confidence that the proposed novel concept can eventually be realized.