Electrocatalytically Upgrading Methane to Benzene in a Highly Compacted Microchannel Protonic Ceramic Membrane Reactor
Project Number
FE0031871
Last Reviewed Dated
Goal
The overarching goal of this project is to develop a significantly process-intensified technology for methane dehydrogenation to aromatic (i.e., benzene) (MDA) in highly compacted microchannel protonic ceramic membrane reactors (HCM-PCMRs) by integrating multiple functions of single-atom catalysis, electrocatalysis, membrane catalysis, membrane separation, and advanced manufacturing.
Performer(s)
Clemson University - Clemson, SC 29634
Oak Ridge National Laboratory (ORNL) - Oak Ridge, TN 37830
Background
The current technologies for natural gas to liquid (GTL) are facing significant challenges: 1) the deployment and intermittent operation at isolated sites often lack convenient access to electricity, make-up water, and other required services; and 2) the GTL technologies (e.g., indirect catalytic conversion of methane to liquid chemicals via synthesis gas) are confirmed to be complicated, inefficient, and environment unfriendly (enormous CO2 emission), requiring large economies of scale to compete in existing commodity markets, and relying on extensive supporting infrastructure to be available. This three-year project will be conducted by a multidisciplinary team consisting of researchers from Clemson University and Oak Ridge National Laboratory, to develop a significantly process-intensified technology for methane dehydrogenation to aromatic in highly compacted microchannel protonic ceramic membrane reactors.
Impact
The major benefits of the proposed technology, as compared with state-of-art industrial GTL technology, are: 1) highly intensified process: highly compacted catalytic membrane reactors; 2) long term stability: less coke problem because of single-atom catalyst and small amount oxygen ion; 3) high benzene yield at a lower temperature: single-atom catalyst, membrane separation, and membrane catalysis; 4) high volumetric performance: microchannel design; 5) isolated operation: co-production of electricity or hydrogen; 6) flexible and cost-effective manufacturing: integrated additive manufacturing and laser process.
Accomplishments (most recent listed first)
Tested theoretical energy requirement of MDA in electrocatalytic protonic ceramic membrane reactors.
Reproducible, high-quality, tubular PCMRs with the targeted area (>10cm2 ) and peak power density (300mW/cm2 at 650°C) were fabricated successfully by an Integrated Additive Manufacturing and Laser Processing (I-AMLP) technique. The PCMRs are ready for long-term testing of fuel cell performance.
Completed a long-term test of tubular PCMRs in the fuel cell mode. The successful test lasted for more than 250h.
Manufactured interdigital microchannel PCMRs with channel width around 200μm-300μm and fully dense membranes.
Developed the testing reactor for running MDA using tubular single-cell with packed catalyst powders.
Directly compared fixed-bed type reactor (FBR, black) with co-ionic membrane reactor. Found a catalyst for converting methane to benzene at a low reaction temperature but also demonstrated the effectiveness of the co-ionic membrane reactor.
Promising preliminary results on the fabrication of microchannel membrane reactors by the I-AMLP technique. Appropriate parameters for paste preparation, paste extrusion, CO2 laser drying, and picosecond laser cutting were adopted to manufacture microchannel membrane reactors. Clean and cut-through microchannels and dense microchannel walls were obtained.
Achieved microchannels with a width of ~250μm, a depth of ~2mm, a wall thickness of ~300μm, and a length of 14mm. The six parallel microchannels have a total effective membrane area of ~336mm2.
Installed new gas chromatograph with thermal conductivity detector (TCD) and flame ionization detector (FID), integrated it with mass spectroscopy, and solved reaction production quantification challenges, allowing accurate online analysis of the methane conversion product.
Fabricated more than six (6) tubes using integrated additive manufacturing and laser processing and constructed tubular protonic ceramic membrane reactors. However, the leak was commonly observed. We tried to address this issue by improving the seal.
Developed alternative planar PCMRs by laser 3D printing method. The single cells based on BCZYYb7111 electrolyte and BCZYYb+NiO cathode were fabricated. The sealing issues for planar PCMRs were solved.
Developed alternative planar PCMRs by laser 3D printing method. The single cells based on BCZYYb7111 electrolyte and BCZYYb+NiO cathode were fabricated. The sealing issues for planar PCMRs were solved.
Installed and calibrated the new gas chromatography system for quantifying the MDA reaction products. It is ready to accurately analyze MDA reaction products.
Printed 3-layer single cells comprised of BCZYYb4411+1wt%NiO electrolyte, 40wt%BCZYYb4411 +60wt% NiO anode, BCZY63 cathode scaffold.
Printed and laser sintered 2-layer half cells comprised of BCZYYb4411 + 1wt% NiO electrolyte, 40wt% BCZYYb4411 + 60wt% NiO anode.
Current Status
Current plans for this project include, 1) testing long-term fuel cell operation for PCMR, 2) infiltrate MDA catalyst to PCMR and test MDA in PCMR, 3) continue to improve MDA catalysts, 4) work on microchannel reaction manufacturing and 5) work on manuscripts.
