Inga H. Musselman - US grants

0933563
Ferraris


This NSF award by the Chemical and Biological Separations program supports the work by Professor John P. Ferraris, Kenneth J. Balkus, Jr., and Inga H. Musselman at the University of Texas at Dallas to design, fabricate and test mixed matrix membranes (MMMs) for gas separations. This project will utilize novel materials that simultaneously target selected separations and provide improved interfacial contact with the polymer matrix. We have discovered that high loadings of nanoporous metal-organic frameworks (MOFs) in polymers can provide the long sought after breakthrough technology. MOFs offer some of the highest surface areas ever reported as well as the selective adsorption of gases involved in industrially important separations including CO2, CH4, O2, and N2. Many of these metal-organic frameworks have exceptional thermal and chemical stability such that MOFs could be competitive with zeolites for commercial separations. This novel class of materials has enabled us to fabricate MMMs with unprecedented loadings [>80% (w/w)], which we believe is the key to finally realizing the promise of mixed-matrix membranes for gas separations.

The broader impacts of this project on energy and the environment include numerous tasks that will lead to the integration of research and multilevel education in the area of membrane science and novel nanomaterials. The success of this potentially high impact research effort will lead to significant benefits to society including replacement of energy-intensive separations with membranes resulting in both energy and economic savings. A strong educational component will coincide with the research activities that will engage students at both the graduate and undergraduate levels as well as students from underrepresented groups and women. The skills acquired by students during this project will enhance their preparation for careers in membrane engineering, nanotechnology, energy, and materials science. In addition to seminars and course development on membranes and their applications, we seek to engage students at all levels in the study of membranes and nanomaterials. We are also committed to high school student research experiences through a number of summer programs and anticipate that this project will also impact the community at large by educating our high school teachers and students.

Ferraris, John
1403950
Novel Nanostructured Membranes for Gas Separations

Polymer membranes for gas pair separations exhibit an inverse relationship between gas selectivity and gas flux. Maximizing both would be a significant advance. The idea of combining the selective separation properties of porous inorganic materials with the processability of polymers has resulted in several advances. Nevertheless, it appears that the performance of such membranes has reached a plateau, and a new approach will be needed to achieve a revolutionary breakthrough in membrane-based gas separations. The PIs have discovered that membranes constructed from otherwise immiscible polymers can be engineered at the nanoscale through the addition of small amounts of porous nanoparticles.

The major limitation with current mixed matrix membranes (MMMs) for gas separations is their low gas flux, primarily due to the membrane thickness (>several tens of micrometers) that is required to accommodate the porous additives. Colloidal ZIFs with particle diameters of <60 nm will enable the selective polymer layer to be submicrometer in thickness, and the matrix-droplet geometry will increase the interfacial surface area by 50 to 100X compared to a layer-by-layer morphology, greatly increasing flux while maintaining superior permselectivity. In order to fully utilize this novel membrane architecture, a thorough understanding of the thermodynamic and kinetic factors that control the structure will also be researched.

Combining the selective separation properties of inorganic molecular sieves with the processability of polymers to form mixed-matrix membranes (MMMs) has resulted in several advances including the incorporation of porous additives such as metal organic frameworks (MOFs) and zeolitic imidazolate frameworks (ZIFs). The organic-inorganic hybrid nature of these additives has afforded improved interfacial contact with the polymer matrix, enabling very high loadings in the MMMs.

The PIs propose a unique membrane architecture comprising blends of otherwise immiscible polymers that can be engineered at the nanoscale through the addition of small amounts of ZIFs. By choosing component materials with appropriate interfacial/surface tensions, the ZIF nanoparticles localize at the interface between the polymers. This has the advantage of compatibilizing high performance immiscible polymers thus greatly expanding the number of polymer combinations that can be utilized.

The proposed research will develop membranes comprising thin, continuous ribbons of a highly selective polymer embedded in a discontinuous matrix of a second, highly permeable polymer, somewhat akin to the marbling in USDA Prime Beef. Such architectures will significantly improve the performance of membranes, especially by increasing flux and selectivity at lower additive loadings, thus reducing cost. This project on energy and the environment includes numerous tasks that will lead to the integration of research and multilevel education in the area of membrane science and novel nanomaterials. The replacement of energy intensive separations with membranes could result in economic savings. This level of structural control could also be potentially useful for fuel cell applications and other separations. Additionally, the strong educational component coinciding with the research activities will engage students at both the graduate and undergraduate levels, as well as students from underrepresented groups and women. The skills acquired by students during this project will enhance their preparation for careers in membrane engineering, nanotechnology, energy, and materials science. We are also committed to high school student research experiences and we anticipate that this project will also impact the community at large by educating our high school teachers and students.





SIGNATURE

Name: Rosemarie D. Wesson
Title: Program Director
Program: Chemical and Biological Separations


DATE: April 2014

The University of Texas at Dallas (UT Dallas) will be Adapting Successful Practices to foster an Inclusive, Respectful, and Equitable Environment (ASPIRE2) to significantly and systematically transform the campus in ways that will expand and enrich the diversity of its faculty in STEM fields and beyond. Through the ASPIRE2 Project, UT Dallas will adapt and implement successful activities to foster a more inclusive campus climate, recruit more women in STEM fields, (including women of color and women from underrepresented minority groups), and aid in the retention of all women faculty, in STEM and across campus. The goal of the project is help UT Dallas, a major research university, better reflect and represent the world in terms of gender and racial diversity. By doing so, UT Dallas can better serve its community, state and country, helping solve the national crisis of the disproportionate lack of tenured-system women, especially in STEM fields.

The outcomes of the ASPIRE2 Project are expected to bring about structural and cultural transformation and tackle persistent problems in innovative and intersectional ways. The ASPIRE2 activities include: Climate (training for deans, department/program heads, and faculty will be conducted; a department/program head council will be formed; an Advocates and Allies Program will be developed; a biennial climate survey will be administered; and equity dashboards for the University and individual schools will be instituted), Identification and Recruitment (Activities include future faculty career development workshops, paying careful attention to the composition of and training for search committees, and providing faculty liaisons to search committees), and Retention and Advancement (strengthening the existing faculty mentoring program, creating a Women in STEM employee resource group, and augmenting existing workshops for faculty promotion and tenure). This project will enhance the climate on the UT Dallas campus while broadening the participation and success among women faculty, particularly women of color and women from underrepresented minority groups. Building on existing efforts, UT DALLAS is well-poised to create a more welcoming and inclusive environment by adapting previously vetted initiatives and strengthening the relationships across campus between administrators, faculty, and staff through the ASPIRE2 activities. Increasing faculty diversity will fuel new research collaborations while enriching teaching, learning and the overall student experience. The NSF ADVANCE program is designed to foster gender equity through a focus on the identification and elimination of organizational barriers that impede the full participation and advancement of diverse faculty in academic institutions. Organizational barriers that inhibit equity may exist in policies, processes, practices, and the organizational culture and climate. ADVANCE "Adaptation" awards provide support for the adaptation and adoption of evidence-based strategies to academic, non-profit institutions of higher education as well as non-academic, non-profit organizations.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.