Inorganic Membranes and Their Reactive Applications
Worcester Polytechnic Institute: William W. Durgin,
Yi Hua Ma, Francis B. Manning of Chemical Engineering, Co-Principal
Investigator
University of Southern California: Theo Tsotsis, Robert E. Vivian Professor of
Chemical Engineering, Co-Principal Investigator
Arizona State University, Jerry Y. S. Lin, Professor of Chemical Engineering,
Co-Principal Investigator
Abstract
Inorganic membranes have gained considerable attention in the past several years.
Both porous and dense inorganic membranes are suited for gas separation and reaction
applications. Although dense inorganic membranes have the advantage of high separation
factors (theoretically infinite), their low permeation flux is a major drawback. Operating
the membrane at high temperatures and using a thinner membrane layer supported on a
porous structure can increase the flux to a commercially viable level. On the other hand,
supported porous ceramic membranes possess the unique properties of the unusual
chemical and thermal stability although their separation factor for gaseous mixtures in
some cases, may be too low for some practical applications. However, the synthesis of
membranes with pore size of molecular dimension can increase the separation factor
possibly comparable to their dense counterpart. This proposal describes the collaboration
among academic institutions, national laboratories and industry for three important areas
of inorganic membrane research.
1. Fundamental understanding of mechanisms for the synthesis of composite Pd/Pdalloy porous stainless membranes for reforming reaction applications including
methane steam reforming and dry reforming with CO2
The application of membrane technology to a thermodynamically restricted reaction,
such as steam reforming of natural gas to form hydrogen and carbon dioxide and the
dry reforming of natural gas with carbon dioxide to obtain hydrogen and carbon
monoxide, is a research field of great interest nowadays. The steam reforming of
natural gas is currently the most efficient and economic process for hydrogen
production, while the dry reforming reaction is an interesting alternative for carbon
dioxide recycling by converting it to synthesis gas, which can be used in chemical
energy transmission systems or utilized in the Fischer-Tropsch reaction to produce
liquids. This latter approach would be especially useful at remote natural gas fields
containing large amounts of CO2 and at petroleum fields where natural gas is now
being flared because liquids can be transported less expensively than gases. Carbon
dioxide recycling would have a significant impact on reducing emissions of this green
house gas in a large-scale energy conversion process.
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Possible collaboration organizations with WPI’s group for this project include Shell
International Exploration and Production Inc., Shell Hydrogen, NETL (National
Energy Technology Laboratory) and Oak Ridge National Laboratories (ORNL).
2. Membrane Applications under Supercritical Conditions.
In this project we will focus on the application of nanoporous membranes under
supercritical (SC) conditions involving “green” solvents like SC CO2. This project
will be carried out collaboratively between USC and the University of Montpellier,
France, under the direction of Professors M. Rios and J. Sanchez of the Department
of Chemical Engineering. USC has been specializing in the separation of
hydrocarbon mixtures under supercritical conditions using nanoporous carbon
molecular sieve membranes (CMSM), while the focus of the French group is mostly
on membrane reactor applications. The collaborative effort will focus on combining
the expertise of the USC group in the preparation of defect-free CMSM, and their
ability to model transport/reaction phenomena under such conditions, with the
expertise from industries.
Possible collaboration organizations with USC’s group for this project include
Chevron Texaco, Johnson and Matthey and the Gas Company of Southern California.
3. Zeolite membrane reactors for reactions with controlled reaction pathway
Almost all work reported on the membrane reactors is based on the concept of
manipulating the reactant contact mode or product removal scheme to facilitate
separation of products/reactant and improve the reaction selectivity and yield. Few
studies have been reported on membrane reactor that can manipulate the reaction
mechanism to favor the formation of desired products or improve the properties of
specific products. In his project we will work on developing zeolite membrane
reactors for chemical reactions with reaction mechanism manipulated to obtain
desired products or improve product yield. In particular, we will focus on ZSM-5
type zeolite reactors for effective synthesis of para-xylene, an important raw material
for polyester fibers and films.
Possible collaboration organizations with ASU’s group for this project include Oak
Ridge National Labs, Corning Inc, The BOC Group, Gas Technology Institute and
Sintef.
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