Michael Tsapatsis, Ph.D. - US grants

CTS-9512485 Tsapatsis U of Massachusetts A Powder X-ray Diffractometer (PXRD) will be procured for research in material characterization. The PXRD will have capabilities for in situ high temperature, controlled environment and thin film XRD. Uses for the equipment include characterization of synthetic zeolites, polymeric materials and amphiphilic association structures, as well as identification of layered silicates and other minerals in geological samples. It will support various research projects in advanced materials processing and manufacturing. The PXRD will also be used for training of graduate students.

Watkins - 9811088 The development of functional, nanostructured metal composite membranes will have a substantial economic impact on the separation, purification and recovery of gases as well as novel membrane reactor applications for oxygen-enriched combustion, controlled partial oxidation and equilibrium limited dehydrogenation reactions. Despite progress that has been achieved to date, precise control of deposit microstructure, composition and distribution within the support has not been realized. The challenge for porous-inorganic support/metal composites remains the development of methodologies for the controlled infiltration and deposition of nanostructured metal and metal alloys within interior pores at a prescribed depth and thickness. These architectures are inaccessible by current techniques including chemical vapor deposition, metal sputtering and electroless plating due to constraints of these processes that do not allow for optimization of deposit microstructure or composition. Polymer/metal composites membranes are plagued by poor and to rectify this deficiency, processes leading to gradient interfaces are required. The PI's plan to integrate materials synthesis, characterization and multi-scale simulations for the development of a processing strategy based on the concept of chemical fluid deposition (CFD). CFD is a form of metal deposition that involves the chemical reduction of soluble organometallic compounds in supercritical carbon dioxide solution. The key to the process is physicochemical properties of the solvent which lie intermediate to those of liquids and gases. Transport and reduction in solution offers low process temperatures, high reagent concentrations and eliminates precursor volatility requirements associated with vapor phase techniques. The absence of surface tension and low viscosity of supercritical fluid (SCF) solutions are well suited to the delivery of relatively high concentrations of organometallic precursors within porous environments. Deposi tion is triggered by the introduction of a reducing agent to produce metal deposits. This reaction scheme can be used to dictate deposit composition and microstructure via direct control of nucleation and growth kinetics by precise adjustments in stoichiometry of the soluble precursors. Mass-transport limitations are largely eliminated due to high precursor concentration and favorable transport properties of the SCF solution which is similar to those of a gas. The permeability of polymer substrates to SCF/organometallic solutions can be exploited to produce composite membranes with adherent, gradient polymer/metal interfaces and metal interlayers.

ABSTRACT
CTS-0079451
Michael Tsapatsis

The Department of Chemical Engineering at the University of Massachusetts Amherst will purchase a gravimetric system for sorption studies in porous solids. The system that will be acquired and assembled is built around an in situ gravimetric adsorption system designed to operate from vacuum (10-6 torr) to 10 bar and from -195 C to 500 C. This system measures the weight of a powdered sample in contact with a flowing gas or mixture of gases. The adsorption, desorption or
reaction on the solid is followed by the change of mass in time. On-line mass spectrometry or an on-line infrared detection system monitors the compositions of the gases passing over the sample allowing competitive adsorption studies.

A common theme in the current projects of the investigators to be supported under this effort is the adsorption and transport properties of gases and vapors in microporous and mesoporous media. A wide range of activities is centered in this theme ranging from fundamental studies of adsorption equilibrium in porous media to practical applications of these materials in the forms of powders, monoliths and membranes for gas and organic vapor separations. Examples of activities include:
Development of zeolites and other molecular sieve adsorbents and
membranes
Understanding hysteresis in adsorption isotherms
Adsorbent structure modification during adsorption
Phase transitions in porous media
Development of new techniques for microstructural characterization of
fabricated porous media

The research to be carried out using the system is all currently funded from Federal sources and grants from private research foundations and US industry (NSF, ATP, NASA, DOE, The David and Lucile Packard Foundation, The Camille and Henry Dreyfus Foundation, Engelhard Co.). Five faculty members and their research groups currently consisting of over twenty-five graduate students and post-doctoral workers and more than ten undergraduate students will use the equipment requested in this proposal.

Abstract
CTS-0103010
P. Monson, U of Massachusetts Amherst

This proposal was submitted in response to solicitation "Nanoscale Science and Engineering (NSF 00-119)" and requests support for an interdisciplinary research program concerned with understanding the growth of nanoporous materials- focusing on zeolitic materials. A research program in this area will have immediate impact on an enormous worldwide effort for developing porous materials with properties tailored at the nanoscale for applications such as catalysis or separations. Moreover, a central feature in the growth of such materials is the assembly of supramolecular precursor particles to form complex organic-inorganic structures with crystalline order. This mechanism is paradigmatic for the synthesis of a whole range of new materials, ranging from substrates for quantum confinement and laser applications to biomaterial implants with controlled porosity and nanostructure.


The proposal has its origin in a collaboration among some of the PI's on the problem of crystal growth of silicalitc-1 zeolite, in which important features of a growth mechanism involving the formation and assembly of subcolloidal zeolite particles were elucidated. The collaboration featured both experimental work and modeling of the growth process. As this work developed it became clear that further progress would be greatly enhanced with a larger research team. In particular, it was clear that expertise was required in detailed atomistic modeling of the growth process as well as in characterization by light scattering and atomic force microscopy. The NSF NIRT initiative has created an opportunity for this research team to come to full fruition. Our interdisciplinary team involves researchers in four departments at the Universities of Massachusetts and Delaware, partnerships with companies at the forefront of applications of nanoporous materials and collaboration with a government laboratory.

The project is divided into two main research areas:

Synthesis, Purification and Structure of Subcolloidal Particles:

Assembly of Subcolloidal Particles and Silicalite Crystal Growth

In addition to elucidating fundamental aspects of zeolite growth, we anticipate that in the longer term our research will lead to novel assembly methods and the development of new materials grown by assembly of subcolloidal zeolite particles. Each of our research areas will feature both experimental and modeling investigations. A spectrum of modeling techniques will be employed spanning length scales from the atomistic level, required to understand the formation and structure of subcolloidal zeolite particles, to the mesoscopic level, required to understand the crystal growth habit of zeolite materials.

The research program has substantial educational component including: the development of new graduate courses on nanoscale materials and on computational materials science at both partner Universities, industrial internships for graduate students and postdoctoral scholars, as well as involvement of undergraduate students in the research.

CTS-0107488
Eva Marand
Virginia Polytechnic Institute and State University
The Development of Mixed-Matrix Membranes


Abstract


Membrane separations represent a growing technological area with potentially high economic reward due to low energy requirements and facile scale-up of membrane modular design. Advances in membrane technology, especially in novel membrane materials, will make this technology even more competitive with traditional, highly energy-intensive, and costly processes such as low-temperature distillation and adsorption. In particular, there is need for large-scale gas-separation-membrane systems that can accomplish processes such as nitrogen and oxygen enrichment, hydrogen recovery, acid gas (CO2, H2S) removal from natural gas, and capture of greenhouse gases as well as separation of various hydrocarbon mixtures. Materials employed in these applications must offer durability, productivity, and highly selective separation performance if they are to be economically viable. Currently, polymers and certain inorganic membranes are the only candidates, and each of these two classes has limitations.

The goal of this research is to develop structured composite zeolite/polyimide thin-film membranes that will exhibit gas-separation performance superior to that of existing polymer-based membranes and which will retain their processing versatility and ruggedness compared to inorganic membranes. This work incorporates anisotropic ETS-4, ZSM-2, LTL and MFI plate-like molecular sieves in mixed-matrix membranes. These zeolites can be produced with controlled nanometer-scale size distribution and surface functionalization. The success of the mixed-matrix materials lies in the elimination of defects at the molecular sieve/polymer interface and in the control of the film's microstructure at the sub-nanometer level. This can be achieved by employing zeolite nanoparticles with functionalized surfaces to promote bonding with the polymer matrix. A series of new, well-characterized polyimides has been developed with pendant carboxylic functional groups to serve as the membrane matrix. These polyimides already have excellent separation properties for various gas mixtures and are thermally stable above 400oC in air. A defect-free polymer-zeolite interface is achieved by forming hydrogen bonds or direct covalent linkages between the polyimide chains and the functionalized zeolite nano-particles.

Proposal No.: CTS-0091406
Proposal Type: Investigator Initiated
Principal Investigators: Michael Tsapatsis
Institution: University of Massachusetts Amherst


Towards High Selectivity Molecular Sieve Membranes through Microstructural
Optimization

The objective of this project is to relate the microstructure of polycrystalline zeolite films to membrane separation performance. The project involves the study of two classes of films of the same zeolite (high-silica MFI) with distinctly different microstructure, stability and separation performance. These films are prepared by the secondary growth technique. Optical and electron microscopy are combined with X-ray diffraction to unravel the microstructural differences of these films at the nanometer level. The structural information is used to relate these differences to membrane properties like
selectivity and susceptibility to membrane cracking. Approaches for avoiding crack
formation and methods for selective crack sealing are being investigated.

Zeolites and related molecular sieves are crystalline materials with microporous frameworks capable of filtering molecules at the subnanometer level. The formation of crystalline molecular sieve membranes enables separations of molecules with similar physicochemical properties that are difficult to separate by other methods. As a result,
efforts towards zeolite membrane preparation are receiving increasing attention worldwide. Recent advances have resulted in commercialization efforts and suggest new opportunities for applications in gas, liquid and vapor separations. Potential applications include separations of specialty chemicals, hydrocarbon isomers, and permanent gases as well as water/alcohol solutions by pervaporation. In order to sustain the initial success of first-generation zeolite membranes, and to find uses in new processing strategies unattainable with the current membrane technology (e.g., isomerization membrane reactors, chiral separations, etc.), research efforts are required that will combine synthetic innovation with fundamental understanding of the synthesis-microstructure-performance
interrelationships. This work emphasizes the microstructure-performance issues. Its outcome will contribute to the development of rational rather than trial-and-error strategies for the formation of high performance molecular-sieve membranes tailored to specific separation applications.

Abstract

Proposal Title: TSE: Layered Silicates with 3-D Microporous Layers: Synthesis and Modification for Membrane Applications

Proposal Number: CTS-0327811
Principal Investigator: Michael Tsapatsis
Institution: University of Minnesota


The objective of this proposal is to synthesize novel layered silicate materials with three-dimensional porosity (AMH-3) as a new class of membranes. The work will focus on understanding the growth of AMH-3 to guide the synthesis of other three-dimensional microporous layers and to modify AMH-3 to make it compatible with nanocomposite processing techniques and to tailor the gas adsorption properties of the silicate layers. Characterization techniques will include SEM, TEM, NMR, IR, Raman, gas adsorption as well as synchrotron X-ray and neutron powder diffraction at Brookhaven National Laboratory and NIST. When these inorganic materials are incorporated in polymeric materials, they should retain polymer processability while improving permselective properties due to the superior ability for molecular recognition of the microporous component. In terms of the broader impacts, this work should have an impact on membrane technology with wider implications in the generation of nanostructured functional materials such as catalysts, sensors and adsorbents. The work will contribute to the education of graduate and undergraduate students in an emerging area of fundamental interest and of technological and environmental significance.

Proposal Title: NIRT: Fabrication of Hollow-fiber Polymer/Porous-layer Nanocomposite Membranes for Gas Separations
Proposal Number: CTS-0403574
Principal Investigator: Michael Tsapatsis
Institution: University of Minnesota - Twin Cities



This proposal was received in response to Nanoscale Science and Engineering initiative, NSF 03-043, category NIRT. The objective of this project is to study the synthesis and properties of nanostructured inorganic/polymer composites for application in gas separation technology. Flakes of clay will be incorporated into polymers and fabricated into tubes used in gas separation experiments. The blend of experiment and modeling will provide an underlying basis for understanding the compatibility of the polymeric and inorganic constituents. The effect of structural properties on permeability at different length scales will be probed. By spanning several length scales, including the nanoscale, the team will contribute to fundamental knowledge regarding the behavior of nanoscale materials. The team plans to extend their work to developing new approaches to making layered composites. In terms of the broader impacts, education and outreach activities center on undergraduate research and research experiences for K-12 teachers. A collaborative effort with a Czech group will focus on the development of charged, polyelectrolytes, which could be used in the fabrication of porous layer nanocomposite membranes. There are strong ties to industrial partners that can help transfer technology in the fabrication of improved membranes.

Abstract

Proposal Title: High-flux, High-selectivity MFI Molecular Sieve Membranes: Microstructure Control and High-temperature, High-pressure Use
Proposal Number: CTS-0522518
Principal Investigator: Michael Tsapatsis
Institution: University of Minnesota

The objective of this project is to synthesize highly oriented micrometer-thick MFI films on tubular porous stainless steel supports, and to test their performance under high temperature membrane reactor conditions. It is also proposed to extend the current methodology and prepare for the first time three types of membranes with the three main pore orientations (straight, zig-zag, tortuous) of the MFI structure perpendicular to the film surface and examine their microstructure and separation performance. The level of microstructural control that will be demonstrated will bring practical zeolite polycrystalline thin films as close they can be to single crystals. The microstructure will be characterized and separation performance will be measured. In addition to their practical significance (identifying high performance microstructures), the proposed experiments are of fundamental significance because they will provide the first set of gas and vapor permeation data through zeolite membranes of a given structure type with drastically different preferred orientations. Such a data set is expected to be valuable in providing a connection between microstructure and membrane performance and to guide further developments in the field of inorganic membranes. The proposed research will have broader impacts on the worldwide effort for developing energy efficient separation technologies. High quality film growth on commercial, high-flux, stainless steel supports is a necessary step towards scale up and to make our membranes available to the separations and reaction engineering communities. Moreover, the engineering issues that will be addressed with respect to oriented assembly of inorganic nanoparticles on surfaces and control of templated crystal growth are central for the fabrication of functional nanostructures. Consequently, an entire range of new technologies at the nanoscale, ranging from sensors to catalysts with controlled porosity and nanostructure may be affected by the findings of the current effort. The research program has an educational component including involvement of undergraduate students in the research and a well-defined outreach effort. This project may stimulate the development of new separation processes and catalytic membrane reactors.

This research was received in response to the Active Nanostructures and Nanosystems initiative, NSF 06-595, category NIRT. Its focus is on one of the most promising developments in the field of separations: molecular sieve or zeolite membrane technology. It has become evident that zeolite membrane technology for large scale processes depends on reliable manufacturing that can generate large membrane areas while achieving essential film characteristics: film continuity with low defect density, appropriate pore orientation, and small membrane thickness well under the micrometer range. This NIRT team undertakes the challenge to make the leap forward towards developing such a process.

In the last decade, a set of mechanistic principles for the nucleation and growth of certain molecular sieve materials has been identified. These principles motivated the research experimental efforts, which attempt to control size and shape of zeolite nanoparticles to an unprecedented level and use these nanoparticles as precisely engineered building blocks for molecular sieve thin films made by hierarchical nanomanufacturing. It was hypothesized that synthesis in a confined environment will enable manipulation and control of undesirable aggregation steps and will ultimately yield the desirable perfection in zeolite particle shape and the needed monodispersity in size. The precisely shaped nanoparticles will be used subsequently as building blocks to form closed packed, crystallographically aligned, monolayers using reactive attachment. Following secondary growth, the developed continuous films will be tested for permeation properties, and their microstructure and performance will be compared with the current state-of-the-art. Significant molecular sieve membrane capital and operating cost benefits are the expected outcome of the proposed work. These improvements represent a major leap forward for wider use of energy efficient molecular sieve membrane separation technology. In addition to enabling the thinnest, and consequently most productive, zeolite membranes ever made, the research hierarchical film processing technology may impact other technologies, like microelectronics and sensors. One of these potential uses, i.e., low-k dielectrics for microprocessors, will also be evaluated.
Separations currently represent 15% of global energy consumption. With the global commodity production expected to increase six-fold by 2040, a business as usual scenario is not sustainable. An order of magnitude increase in efficiency of separation and purification processes is a necessary step towards sustainable global prosperity. One of the most promising developments in the field of separations using membranes is that of molecular sieve or zeolite membrane technology. By enabling separations with molecular resolution to replace thermally driven processes, it can meet this efficiency goal and is emerging as an area of nanotechnology and energy research. Zeolites and other molecular sieves are crystalline inorganic frameworks with pores capable of recognizing molecules by shape and size. This ability, along with their thermochemical stability and catalytic activity, has led to their use in a broad variety of applications as catalysts, adsorbents, and ion exchangers. The desire of incorporating these materials in thin film devices with molecular resolution can be traced back in the 1940's. However, it has been only about a decade since the first commercial zeolite membranes targeting small scale distributed applications (i.e., membrane modules of about ten square meters) became available. Since then, commercialization progress has been stagnant, hampered by problems in scale-up from laboratory to commercial scale. The proposed comprehensive and systematic investigations will lead to the development of a scalable and economic fabrication technique resulting in the thinnest zeolite membranes ever made transforming the vision of energy efficient molecular sieve membranes to a commercial reality.

The viability of xenotransplanted cells could be dramatically improved through immunoisolation by permselective encapsulation. The ideal capsule would simultaneously protect the cell from immunological attack, transport nutrients, and release therapeutic cell metabolites (e.g., insulin). Despite recent progress, persistent challenges include the lack of fine control over pore size and encapsulation thickness, the latter leading to mass transport limitations, cell necrosis, and slow cellular response to external stimuli. Material instability and bio-incompatibility also challenge cell encapsulation.

An exploratory research effort is proposed for the formation of permselective coatings on porcine pancreatic islets using silica nanoparticles. Such coatings may allow unprecedented control over thickness, pore size and active chemical functionality. The proposed work will benefit from collaborations with The Diabetes Institute at the University of Minnesota and derives from the recent identification of a benign (i.e., near-physiological conditions) and controllable means for synthesizing stable silica nanoparticles from 5 to 40 nm, and their ordering into colloidal crystal arrays and thin films.

The infliction of more than twenty million Americans with diabetes motivates the proposed research which aims to realize a novel and potentially high impact solution to the challenging problem of islet xenotransplantation. The success of the proposed initiative is of direct interest to the development of novel permselective membrane materials and applications. In addition, it stands to establish fundamental understanding of nanoparticle-cell association for mass transport control, the implications of which may ultimately influence targeted drug and DNA delivery and non-invasive cellular imaging and tracking.

ABSTRACT

PI Name: Michael Tsapatsis
Institution: University of Minnesota-Twin Cities
Proposal Number: 0937706

EFRI: EFRI-HyBi: Conversion of Biomass to Fuels using Molecular
Sieve Catalysts and Millisecond Contact Time Reactors

The practical exploitation of biomass as a carbon-neutral source of fuels requires the development of small distributed production systems capable of processing solids and chemical conversion technologies that can overcome the recalcitrance of lignocellulosic biomass. While several processes for biomass utilization have been proposed, none meets the productivity, scalability, product distribution and economic requirements for commercial implementation. The objective of the proposed research is to develop a continuous and scalable autothermal catalytic process for the "one pot" conversion of lignocellulosic biomass to fuels over metal and zeolites based multifunctional catalysts in a short contact time stratified reactor. Such a process has not been attempted before but feasibility of important elements of the proposed technology were recently demonstrated including: (i) the continuous char-free production of volatile organic compounds from lignocellulosic particles in a short contact time autothermal reactor by Schmidt's group; (ii) the control of mesoporosity at the nanometer level to reduce mass transfer limitations in zeolite catalysts by Tsapatsis' group and (iii) the demonstration of short contact time zeolite catalysis by Bhan using monolith supported thin zeolite films.

Intellectual Merit: The production of fuels from biomass may be accomplished by its conversion to small fragments, the selective removal of oxygen from carbohydrates, and the conversion of small intermediates into larger hydrocarbons via carbon-carbon bond formation. It is proposed to systematically explore possible ways to combine the metal-based exothermic volatilization of biomass with zeolite-based deoxygenation and C-C bond formation in millisecond contact time reactors thereby avoiding deleterious polyaromatic or solid carbonaceous by-products. To realize this transformative concept, emerging frontiers in heterogeneous catalysis, reaction engineering, material design and systems integration will be advanced in the following synergistic research activities:
1. Schmidt, Bhan and Vlachos will combine experiments and multiscale modeling to tune product selectivity towards carbon chain length preservation during biomass conversion in autothermal (partial oxidation) short contact time reactors.
2. Tsapatsis will control meso- and microporosity in zeolite-based thin film catalysts to enable millisecond contact time operation and Bhan will optimize deoxygenation and chain growth reactions with these catalysts. Floudas will perform computational screening to guide the selection of zeolites frameworks while detailed reaction/diffusion and microkinetic models will be developed by Vlachos.
3. Design principles for the "one pot" reactor will be developed and tested by the team of co-PIs.

Broader Impact: Transforming traditional chemical processing and production into a sustainable future is one of the enormous challenges that global society faces. The development of small scale reactor systems capable of processing ligoncellulosic feedstock will lead to new technologies for harnessing diffuse or currently wasted biomass resources and has the potential to contribute to this transformation and the economic growth of the US. The co-PIs will integrate elements of this work as case studies in undergraduate, graduate and topical courses on renewable energy and chemicals, as well as in teaching modules that will be made available on the internet for widespread dissemination. The scope and breadth of the project and the research team further provide unique opportunities for interdisciplinary education of undergraduate and graduate students and students from underrepresented groups. Moreover, an outreach effort to develop related extracurricular activities for middle school students is proposed.

The co-PIs are committed in communicating their work to the public. This will be facilitated by the infrastructure provided by the Institute on the Environment (IonE) at the Univ. of Minnesota and the Center for Catalytic Science and Technology (CCST) at the Univ. of Delaware. Important findings from this work will be included in IonE and CCST sponsored newsletters, press releases, media briefings and public forums.

0855863
Tsapatsis

The practical exploitation of biomass as a carbon-neutral source of chemicals and fuels is limited by the development of process and reaction engineering technology suited for the chemical transformation of hydrophilic, oxygen-functionalized and thermally unstable biomass feedstock. This research seeks to simultaneously harness the shape selective catalytic properties of zeolitic materials and selective separations for implementation in catalytic membrane reactors that will enable low temperature catalytic and separation processes for conversion of sugar monomers, specifically for dehydration of fructose to hydroxymethylfurfural (HMF). It is predicated upon preliminary data that show HMF can be selectively separated from fructose using zeolite membranes and seeks to extend previous work from the PI on the synthesis of high-selectivity, high-permeability membranes for hydrocarbon separations to integrated reaction-separation systems and to polyfunctional biomass-derived feedstock.

Intellectual Merit The project brings together the complementary and diverse experience of the Tsapatsis (zeolitic membranes), Bhan (zeolite catalysis) and Daoutidis (process design and control) research groups to develop new reaction-separation process technologies using biomass as feedstock. Specifically, the co-PIs plan to:
(i) Determine the kinetics, mechanism and site requirements for the dehydration of fructose using steady state and chemical/isotopic transient experimental studies to provide a rigorous description of reaction rates for process design,
(ii) Investigate the potential of zeolite-membranes to separate fructose-derived oxygenfunctionalized molecules and quantitatively assess the effect of adsorption and transport phenomena on the rate and selectivity of HMF production, and
(iii) Design and optimize an integrated reaction-separation system based on (i) and (ii) and also, compare and contrast this methodology at a process engineering level with other reactionadsorption and reaction-extraction biphasic systems proposed in the literature.

The research encompasses the interaction of transport and adsorption phenomena with kinetics in reaction systems for the design of integrated low-temperature reaction-separation systems adapted for the specific molecular structure of biomass feedstock and extends chemical reaction engineering approaches to process intensification to include biomass processing.

Broader Impact Transforming traditional chemical processing and production is one of the challenges the global society faces to ensure a sustainable future. Combination of catalyst development, new materials for separations and energy efficient reaction-purification process integration has the potential to contribute to this transformation. In this respect, the research will have broader methodological impact and may stimulate the development of solutions for other problems related to biorefinery processes. The co-PIs will incorporate elements of this work as case studies in an advanced undergraduate/graduate course that focuses on reaction engineering and separations and in teaching-modules that will be made available on the internet. Undergraduate students will be encouraged to work on aspects of the project and emphasis will be given in recruiting efforts to assure continued diversity within the co-PIs research groups.

0968848
Tsapatsis

This proposal requests partial travel support for participants from the USA to attend the 5th International Zeolite Membrane Meeting (IZMM 2010), held between May 23-26, 2010 in Loutraki-Greece. A part of the requested funds will allow plenary and invited speakers from the USA to attend the meeting and present recent developments in the field of molecular sieve membranes.

IZMM 2010 is the continuation of a successful series including the IZMM conferences at Gifu Japan (1998), Purmerend The Netherlands (2001), Breckenridge Colorado (2004), and Zaragoza Spain (2007). In this focused meeting the scientists from both academia and industry all around the world will be given the opportunity to present, share, and discuss their recent findings and ideas about zeolite membranes, as well as to identify the future challenges of the field. Emerging applications of zeolite films as membrane, nano and micro-reactors for applications in the chemical, petrochemical and biorefinery industry and as components of fuel cells and electronic devices will be discussed. Emphasis will be placed on the technological and scientific challenges that should be overcome for further commercial development of zeolite film based products to solve important societal and technological problems.

The IZMM conference is expected to have significant impact. It will allow to identify the future challenges for research in this rapidly evolving field, it will provide the means for young faculty and graduate students to present their work and establish themselves in the international community and it will catalyze the formation of international collaborations.

An estimated 10-15% of the U.S. energy consumption is devoted to industrial chemical separations. Petroleum refining fractionates crude oil to make gasoline, diesel, fuel oil, as well as chemical precursors that serve as the feedstocks for the majority of consumer goods. Among these petroleum-derived chemical feedstocks is a chemical intermediate, called para-xylene, that is mainly used for the production of poly(ethylene terephthalate) (PET) plastic fibers, films, bottles and packaging materials. With the widespread use of PET, the demand for para-xylene will exceed 60 million tons, with a market value exceeding 60 billion US dollars, by 2022. Prior to its conversion to textiles and packaging plastics, para-xylene must be separated other very similar molecules, called isomers, that differ only by the positioning of a few atoms within the molecule. Given their near-identical chemical structure, it is impractical to separate para-xylene and its isomers from each other by distillation, as their volatilities are very similar. The current state of the art to purify para-xylene is to utilize adsorption and/or crystallization, but both processes are energy intensive. This research project is developing new membranes with high permeance and selectivity that allow continuous separation of para-xylene from its isomers with improved energy efficiency compared with the current state-of-the-art.

Zeolites are hydrated aluminosilicates that are commonly used as cation exchange resins, catalysts, and due to their highly controlled pore size, molecular sieves. Zeolites are stable in organic liquids and vapors at high temperatures and pressures, but until recently, were found only as three-dimensional crystals, which are unsuitable for making thin membrane films. Current zeolite membranes remain too thick to allow high flux of a target molecule and are thus not cost-competitive with other technologies. This research projects is exploring fundamental research on zeolite nanosheet synthesis to make the zeolite crystal ultra thin, which will enable a 10-fold reduction in membrane thickness and a corresponding 10-fold increase in permeance through the membrane. Simultaneously, the research is seeking to reduce membrane defects which is anticipated to increase the separation-factor of para-xylene relative to its isomers 20-fold. Through collaboration with the GOALI industrial partner, Exxon-Mobil, the first-ever systematic permeation measurements are being conducted at the high temperatures and high xylene pressures found at industrially relevant conditions and being coupled with membrane microstructure analysis and quantitative permeation modeling. The work is using electronic structure calculations and molecular simulations to aid in the characterization of the membranes and to predict accurate adsorption-diffusion properties, which will aid in further material design and process optimization. This research on alternative separation technologies is being incorporated as examples in the undergraduate and graduate curriculum and as projects in the process and product design senior undergraduate courses at the University of Minnesota.