Core-Shell Oxidative Aromatization Catalysts for Single Step Liquefaction of Distributed Shale Gas
Project Number
FE0031869
Last Reviewed Dated
Goal
The goal of this project is to design and demonstrate a core-shell structured multifunctional catalyst for single step conversion of the light components of shale gas into liquid aromatic compounds
Performer(s)
North Carolina State University, Raleigh, NC 27695
Background
This project aims to design and demonstrate a core-shell structured multifunctional catalyst for single step conversion of the light components of shale gas into liquid aromatic compounds. Operated in a modular oxidative aromatization system (OAS) under a cyclic redox scheme, the novel catalyst and process can significantly improve the value and transportability of stranded natural gas.
Impact
It is anticipated that the OAS will produce high-value liquid aromatics from low-value natural gas: converting flared and rejected methane (C1) and ethane (C2) alone may lead to a >$5 billion/year value creation. Successful completion of the project will result in optimized OAS redox catalysts with superior aromatics yield (>40% per-pass or 90% overall) and stability (<5% deactivation over 100 hours redox cycles). Realization of these goals will significantly de-risk the scale up and commercialization efforts related to the technology.
Accomplishments (most recent listed first)
Selective Hydrocarbon Combustion (SHC) screening - Seven catalysts screened, four showed satisfactory H2 combustion selectivity (>80%), one showed >200 mol/kgCat-hr activity at 0.1 atm PH2. All four are expected to exceed this activity at >0.5 atm PH2 (based on a reaction order of 1).
Dehydoaromatization Screening (DHA) Catalyst Screening – three (3) or more DHA catalysts screened with > 500 g/kgCat-hr aromatics productivity and > 80% selectivity at <700 °C.
NCSU discovered a steam-resistant catalyst for ethane and ethylene DHA which shows good benzene yield. This DHA catalyst has shown promise to increase the aromatic yield in oxidative coupling of methane OCM + DHA strategy as proposed in the previous quarter.
West Virginia University (WVU), collaborating on this project, continued to improve the zeolite synthesis efficiency by using the microwave-assisted technique and investigated the synthesis conditions on the zeolite yield, crystalline structure and morphology.
Susteon further updated the AspenPlus™ models, which were developed in the previous quarter, to include the OCM+DHA/SHC strategy and estimated a 61% reduction in net energy demand.
Successfully adapted conventional hydrothermal method to be applicable to the microwave synthesizer unit for more efficient catalyst synthesis. Explored a few approaches to further increase the aromatics yield using the OCM+DHA strategy, including changing the space velocity and H2-pretreatment.
The focus was shifted towards the OCM+DHA route which showed significantly higher promise than the original approach due to the lack of stability in steam for the methane DHA catalysts.
Due to the complexity of the aromatic products, focus have been placed on obtaining detailed and reliable carbon balance for the DHA step as detailed in Q11 (this) report. The product yields from OCM catalyst, and the separately tested DHA catalyst performance supports the feasibility of achieving 15% single pass yield under the OCM-DHA approach.
WVU conducted procedural characterizations and catalytic performance testing for the new microwave synthesized catalysts with the newly-developed product analysis procedure. NCSU further optimized the OCM catalyst and the reaction condition to get better catalytic performance for both OCM and OCM+DHA reaction.
Current Status
A final Techno-Economic Assessment (TEA) for the proposed technology will be developed and updated as the research progresses. This project is scheduled to end in June 2023.
