Collaborative Research: A New Class of Chemical Potential Driven Plug Flow Membrane Reactors for Combined Gas Separation and Direct Natural Gas Conversion

University Of South Carolina At Columbia, Columbia SC

Investigators

Abstract

The shale revolution has enabled large volume production of low-cost natural gas. The majority of this resource is still being burned for heat and power, releasing carbon dioxide into the atmosphere and further burdening carbon capture efforts. Meanwhile, directly converting natural gas into valuable chemicals has received significant interest from academia and industry due to the potential profit margin brought by low-cost natural gas. This research project aims to further fundamental scientific knowledge related to carbon dioxide capture, natural gas conversion mechanisms, and catalyst development using a new class of chemical-potential driven (electricity-free), ceramic-based, catalytic plug flow membrane reactors (PFMRs) as a platform. The gas separation and natural gas conversion are unified in a single reactor to be energy efficient and cost-effective. The importance and potential impact of the ongoing scientific advances in carbon dioxide capture and natural gas conversion technologies will be presented to the public during the annual "Edison Lecture Series" program at the University of South Carolina (USC). USC will team up with Benedict College to host a joint summer workshop on energy research topics to promote education and workforce development for students underrepresented in STEM fields. Undergraduate students at Benedict College in engineering majors will be engaged in these research topics by offering summer internships and academic-year part-time jobs, along with having access to USC's and University of Massachusetts at Lowell's (UML) existing undergraduate programs. Two new courses on the topics of gas separation / conversion and computational analysis for electrochemical systems will be independently developed and offered for graduate students at both USC and UML. This research project seeks to develop two specific types of PFMRs. The first is based on a triple carbonate-ion, oxide-ion and electron conductor, and within this reactor the catalytic oxidative coupling of methane will take place using the co-captured carbon dioxide / oxygen mixture to convert natural gas into ethylene in the presence of a suitable catalyst. The second type of PFMR is based on a triple oxide-ion, proton and electron conductor, and within this reactor the catalytic non-oxidative dehydrogenation of methane will be undertaken with the concurrent extraction of hydrogen to convert natural gas into ethylene. For both PFMRs, the influx of carbon dioxide and / or oxygen from the feed side helps significantly mitigate coke formation, thus prolonging the membrane / catalyst life. The fundamental components of the project include developing new membrane compositions and conversion-specific catalysts / supports through a combined experimental and theoretical approach. The fundamental mechanisms governing the methane oxidative and non-oxidative conversions and coke formation will be studied using an isotopic exchange technique and in situ Raman spectroscopy, and the design, testing and modeling of PFMRs via in-house catalytic reactors, multiphysics and system modeling will be performed. 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.