College of Engineering
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The College of Engineering at Montana State University will serve the State of Montana and the nation by fostering lifelong learning, integrating learning and discovery, developing and sharing technical expertise, and empowering students to be tomorrow's leaders.
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Item High Selectivity Reactive Carbon Dioxide Capture over Zeolite Dual-Functional Materials(American Chemical Society, 2024-05) Crawford, James M.; Rasmussen, Matthew J.; McNeary, W. Wilson; Halingstad, Sawyer; Hayden, Steven C.; Dutta, Nikita S.; Pang, Simon H.; Yung, Matthew M.Reactive carbon dioxide capture (RCC) is a process where carbon dioxide (CO2) is captured from a mixed gas stream (such as air) and converted to products without first performing a separation step to concentrate the CO2. In this work, zeolite dual-functional materials (ZFMs) are introduced and evaluated for simulated RCC. The studied ZFMs feature high surface area, crystalline, microporous zeolite faujasite (FAU) as the support. Sodium oxide (“Na2O”) is impregnated as an effective capture agent capable of scavenging low concentration CO2 (1,000 ppm). Exchanged and impregnated sodium on FAU chemisorbs CO2 as carbonates and bicarbonates but does not promote the conversion of sorbed CO2 to products when heated in hydrogen. The addition of Ru promotes the formation of formates, while the addition of Pt generates carbonyl surface species when heated in hydrogen. The active metal then promotes extremely high selectivity for CO2 hydrogenation to either methane on Ru catalyst (∼150 °C) or carbon monoxide on Pt catalyst (∼200 °C) when heated in reducing atmospheres.Item Algal amendment enhances biogenic methane production from coals of different thermal maturity(Frontiers Media SA, 2023-03) Platt, George A.; Davis, Katherine J.; Schweitzer, Hannah D.; Smith, Heidi J.; Fields, Matthew W.; Barnhart, Elliott P.; Gerlach, RobinThe addition of small amounts of algal biomass to stimulate methane production in coal seams is a promising low carbon renewable coalbed methane enhancement technique. However, little is known about how the addition of algal biomass amendment affects methane production from coals of different thermal maturity. Here, we show that biogenic methane can be produced from five coals ranging in rank from lignite to low-volatile bituminous using a coal-derived microbial consortium in batch microcosms with and without algal amendment. The addition of 0.1 g/l algal biomass resulted in maximum methane production rates up to 37 days earlier and decreased the time required to reach maximum methane production by 17–19 days when compared to unamended, analogous microcosms. Cumulative methane production and methane production rate were generally highest in low rank, subbituminous coals, but no clear association between increasing vitrinite reflectance and decreasing methane production could be determined. Microbial community analysis revealed that archaeal populations were correlated with methane production rate (p = 0.01), vitrinite reflectance (p = 0.03), percent volatile matter (p = 0.03), and fixed carbon (p = 0.02), all of which are related to coal rank and composition. Sequences indicative of the acetoclastic methanogenic genus Methanosaeta dominated low rank coal microcosms. Amended treatments that had increased methane production relative to unamended analogs had high relative abundances of the hydrogenotrophic methanogenic genus Methanobacterium and the bacterial family Pseudomonadaceae. These results suggest that algal amendment may shift coal-derived microbial communities towards coal-degrading bacteria and CO2-reducing methanogens. These results have broad implications for understanding subsurface carbon cycling in coal beds and the adoption of low carbon renewable microbially enhanced coalbed methane techniques across a diverse range of coal geology.