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The application of porous heterogeneous hierarchical materials across industries is limitless; their roles as catalysts, adsorbents, ion-exchangers, membranes, antibacterial agents, etc., are constrained only by the ability to design and fabricate new materials systems optimized for various reactive transport processes. These materials often comprise an inert scaffold designed with multiple levels and distributions of porosities, tortuosities and particle sizes, which are decorated with active sites. While the hierarchical structure and chemical composition of such materials are inextricably linked, most design schemes focus on one aspect or another, owing to the complexity in such a holistic design. By coupling rigorous computational and experimental approaches we are developing a new design paradigm that considers both the material properties along with the fabrication and structural aspects of the material system. In this talk we will discuss initial results including the design and optimization of an activated carbon based flue gas filter.
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MULTI-SCALE COMPUTATIONAL FRAMEWORKS FOR HIERACHICAL POROUS MATERIAL DESIGN
By virtue of their extensive potential in energy conversion and storage, catalysis, photocatalysis, adsorption, separation and life science applications, significant interest has been devoted to the design and synthesis of hierarchical porous materials. The main factors which determines the performance of hierarchical porous materials for an application include structure (pore size, porosity, tortuosity), materials (scaffold, dopants) and operating conditions. Traditionally, these hierarchical porous materials are synthesised and fabricated through a manual trial and error procedure, which is an expensive and time-consuming approach. However, there have been significant advances in mathematical, computational and engineering tools toward solving and optimising multiscale descriptions of physical phenomena. This motivates a computational-aided framework to tailor the fabrication of hierarchical porous materials to be optimised in performance for their specific application. In this work, a reactive-transport system in porous media is modelled using computational fluid dynamics. While microscale descriptions are too computationally expensive and macroscale models fail to accurately describe a physical phenomena in specific parts of computational domains, hybrid - or multiscale - algorithms, are used. Using the information provided by the numerical simulation, multiscale model-based design of experiments are developed to optimise the material’s performance on their particular usage. It is proposed that hierarchical multiscale modeling offers a systematic framework for identification of the important scales and parameters where one should focus experimental efforts on.
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- Award ID(s):
- 1727316
- PAR ID:
- 10098539
- Date Published:
- Journal Name:
- ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY
- Volume:
- 256
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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