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Title: Synergistic Enhancement of CO2 Capture via Amine Decorated Hierarchical MIL-101 (Cr)/SBA-15 Composites
Synthesis of amine incorporated hierarchical metal organic framework (MOF) MIL-101(Cr)/SBA-15, meso/ micro-porous composites, with tailored properties for CO 2 capture is reported. The synthesized composites were characterized in terms of their crystallinity, morphology, functional groups, and textural properties. Isothermal adsorption of CO 2 from concentrated sites as well as ambient conditions were evaluated by gravimetric and volumetric measurements. The optimized composite i.e., MIL-101(Cr)/SBA-15/PEI-25 showed improved pseudo- equilibrium adsorption capacity of 3.2 mmol/g at 303 K and 1 bar, compared to nascent SBA-15 (0.8 mmol/g) and the MOF, i.e., MIL-101(Cr) (1.3 mmol/g). Such adsorption performance can be attributed to the basic sites of the impregnated polyethyleneimine (PEI), unsaturated Cr(III) metal sites, and the hierarchical pore structure of the composite which imparts chemical as well physical adsorption forces towards CO 2 lower amine loading of 25 wt% in the composite resulted in facile CO 2 uptake. Interestingly, desorption at much lower temperature of  more » « less
Award ID(s):
1736173
PAR ID:
10574057
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Elsevier B.V.
Date Published:
Journal Name:
System
Volume:
322
Issue:
August 2024
ISSN:
0346-251X
Page Range / eLocation ID:
129533
Subject(s) / Keyword(s):
MIL-101(Cr) SBA-15Carbon capture Hierarchical
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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