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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Upcycling of Waste Plastics into Carboxylic Acids for Biodegradable Surfactants

This work outlines a process for producing high‐purity (>95%) carboxylate surfactants from post‐consumer recycled high‐density polyethylene (PCR‐HDPE). The approach involves the thermal depolymerization of PCR‐HDPE via pyrolysis, followed by fractional distillation to isolate C9–C14 olefins. These olefins undergo hydroformylation using cobalt carbonyl catalysts to generate aldehydes, which are subsequently oxidized to carboxylic acids using Pinnick oxidation under mild aqueous‐phase conditions. Neutralization of the resulting carboxylic acids with sodium hydroxide produces plastic‐derived carboxylate surfactants (PDCs) in the form of sodium carboxylates. Subsequent purification steps ensure surfactant‐grade purity and enable accurate assessment of physicochemical properties. The resulting PDCs are evaluated for critical micelle concentration (CMC), foamability, surface tension reduction, and calcium ion tolerance, demonstrating competitive behavior with conventional anionic carboxylate surfactants. This route provides a sustainable alternative for surfactant production, reducing reliance on fossil‐derived feedstocks and valorizing plastic waste streams through chemical upcycling.

Biodegradable surfactants↗
DOE OSTI2015

Conceptual process design and economics for the production of high-octane gasoline blendstock via indirect liquefaction of biomass through methanol/dimethyl ether intermediates

This paper describes in detail one potential conversion process for the production of high-octane gasoline blendstock via indirect liquefaction of biomass. The processing steps of this pathway include the conversion of biomass to synthesis gas via indirect gasification, gas clean-up via reforming of tars and other hydrocarbons, catalytic conversion of syngas to methanol, methanol dehydration to dimethyl ether (DME), and the homologation of DME over a zeolite catalyst to high-octane gasoline-range hydrocarbon products. The current process configuration has similarities to conventional methanol-to-gasoline (MTG) technologies, but there are key distinctions, specifically regarding the product slate, catalysts, and reactor conditions. A techno-economic analysis is performed to investigate the production of high-octane gasoline blendstock. The design features a processing daily capacity of 2000 tonnes (2205 short tons) of dry biomass. The process yields 271 liters of liquid fuel per dry tonne of biomass (65 gal/dry ton), for an annual fuel production rate of 178 million liters (47 MM gal) at 90% on-stream time. The estimated total capital investment for an nth-plant is $438 million. The resulting minimum fuel selling price (MFSP) is $0.86 per liter or $3.25 per gallon in 2011 US dollars. A rigorous sensitivity analysis captures uncertainties in costs and plant performance. Sustainability metrics for the conversion process are quantified and assessed. The potential premium value of the high-octane gasoline blendstock is examined and found to be at least as competitive as fossil-derived blendstocks. A simple blending strategy is proposed to demonstrate the potential for blending the biomass-derived blendstock with petroleum-derived intermediates. Published 2015. This article is a U.S. Government work and is in the public domain in the USA. Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd.

09 BIOMASS FUELS↗
DOE OSTI2016

Techno-economic analysis of biodiesel and ethanol co-production from lipid-producing sugarcane: Biodiesel and Ethanol Co-Production from Lipid-Producing Sugarcane

Biodiesel production from vegetable oils has progressively increased over the past two decades. However, due to the low amounts of oil produced per hectare from temperate oilseed crops (e.g. soybean), the opportunities for further increasing biodiesel production are limited. Genetically modified lipid-producing sugarcane (lipid-cane) possesses great potential for producing biodiesel as an alternative feedstock because of sugarcane’s much higher productivity compared with soybean. In this study, techno-economic models were developed for biodiesel and ethanol coproduction from lipid-cane, assuming 2, 5, 10, or 20% lipid concentration in the harvested stem (dry mass basis). The models were compared with a conventional soybean biodiesel process model to assess lipid-cane’s competiveness. In the lipid-cane process model, the extracted lipids were used to produce biodiesel by transesterifi cation, and the remaining sugar was used to produce ethanol by fermentation. The results showed that the biodiesel production cost from lipid-cane decreased from $0.89/L to $0.59 /L as the lipid content increased from 2 to 20%; this cost was lower than that obtained for soybeans ($1.08/L). The ethanol production costs from lipid-cane were between $0.40/L and $0.46/L. The internal rate of return (IRR) for the soybean biodiesel process was 15.0%, and the IRR for the lipid-cane process went from 13.7 to 24.0% as the lipid content increased from 2 to 20%. Because of its high productivity, lipid-cane with 20% lipid content can produce 6700 L of biodiesel from each hectare of land, whereas soybean can only produce approximately 500 L of biodiesel from each hectare of land. This would indicate that continued efforts to achieve lipid-producing sugarcane could make large-scale replacement of fossil-fuel-derived diesel without unrealistic demands on land area.

09 BIOMASS FUELS↗
DOE OSTI2017

Economic and life cycle assessments of biomass utilization for bioenergy products

A modeling process was developed to examine the economic and environmental benefits of utilizing energy crops for biofuels and bioproducts. Three energy crops (hybrid willow, switchgrass and miscanthus) that can potentially grow on marginal agricultural land or abandoned mine land in the northeastern United States were considered in the analytical process for the production of biofuels, biopower and pellet fuel. The supply chain components for both the economic analysis and life cycle modeling processes included feedstock establishment, harvest, transportation, storage, preprocessing, conversion, distribution and final usage. Sensitivity analysis was also conducted to assess the effects of energy crop yield, transportation distance, conversion rate, facility capacity and internal rate of return (IRR) on the production of bioenergy products. The required selling price (RSP) ranged from $ 7.7/GJ to $ 47.9/GJ for different bioproducts. The production of biopower had the highest RSP and pellet fuel had the lowest. The results also indicated that bioenergy production using hybrid willow demonstrated lower RSP than the two perennial grass feedstocks. Pellet production presented the lowest greenhouse gas (GHG) emissions (less than 10 kg CO 2 eq per 1,000 MJ) and fossil energy consumption (less than 150 MJ per 1,000 MJ). The production of biofuel resulted in the highest GHG emissions. Sensitivity analysis indicated that IRR was the most sensitive factor to RSP and followed by conversion rate for biofuel and biopower production. As a result, conversion rate and transportation distance of feedstock presented a significant effect on environmental impacts during the production of the bioproducts.

09 BIOMASS FUELS↗
DOE OSTI2020

Moving from residual lignocellulosic biomass into high–value products: Outcomes from a long–term international cooperation

Major progress in the bioprocessing of lignocellulose to fuels and value-added chemicals has created the possibility of a low carbon-footprint economy. However, the current complexity and associated costs of lignocellulose conversion result in a higher price for ethanol than for fossil fuels. The cost of cellulosic ethanol production will be lowered by further progress in development of biorefinery technology that produces both ethanol and high-value chemicals with bio-based products that are beginning to penetrate consumer markets in the USA, Brazil, and worldwide. The cost-effectiveness of low carbon-footprint bioproducts will benefit from advances in supplying large amounts of biomass solids to the biorefinery. We describe here outcomes from a successful long-term international cooperation between the Laboratory of Renewable Resources Engineering (LORRE) at Purdue University in the United States and Brazil's Agricultural Research Corporation (EMBRAPA) and Federal University of Sâo Carlos (UFSCar), which has contributed practical pathways to enhance the biorefinery concept. Furthermore, this paper gives an overview of developments that address fundamental knowledge of lignocellulosic biomass pretreatment hydrolysis under optimized operational conditions and bioreactor configurations, and the science and engineering that contributes to the effective production of fuel and ethanol and value-added products from biomass.

09 BIOMASS FUELS↗
DOE OSTI2023

Effects of soybean varieties on life-cycle greenhouse gas emissions of biodiesel and renewable diesel

This study presents a life-cycle analysis (LCA) of the greenhouse gas (GHG) emissions of biodiesel (BD) and renewable diesel (RD) produced from soybean varieties with altered oil profiles and meal composition. The varieties evaluated include those with high oleic oil content (78% of oil being oleic oil vs. the current content of 25%), high lipid content (25% vs. the current content of 19%) or high protein content (45% vs. the current content of 35%). The results suggest that high-oleic soybean oil could reduce GHG emissions of RD by 1 g CO 2 e/MJ by reducing hydrogen consumption in the hydro-treating stage of RD production. With the default allocation method (mass-based allocation between oil and meal), changes in lipid and protein contents have negligible impacts on GHG emissions of BD/RD pathways. Since high-protein soybean meal has a higher nutrient value, we employed the market-based allocation for sensitivity analysis. Assuming a market price of $1.17/dry kg and an average of two substitute feeds with similar protein contents (corn gluten and fish meal), the allocation factor for soybean meal increases from 63 to 81%. Compared with the results for the case with commodity soybean using mass allocation, GHG emissions could be 1.9 and 1.8 g CO 2 e/MJ lower for BD and RD, respectively. In addition to product-level LCA, we employed a land-based LCA to evaluate the effect of soybean properties on product slates with the same land area and the associated displacement of conventional products. The results suggest that high-lipid soybeans may offer more GHG savings than other varieties as the higher BD/RD yield replaces more fossil diesel. © 2023 UChicago Argonne, LLC, Operator of Argonne National Laboratory and Northrup, Ag. Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd.

09 BIOMASS FUELS↗
DOE OSTI2023

Selective Valorization of CO 2 towards Valuable Hydrocarbons through Methanol-mediated Tandem Catalysis

The thermocatalytic conversion of carbon dioxide (CO 2 ) into valuable hydrocarbons presents a promising solution for mitigating anthropogenic CO 2 emissions while producing drop-in replacements for fossil-derived products. Among the two tandem mechanisms for the direct hydrogenation of CO 2 , the methanol synthesis coupled with the methanol to hydrocarbon (MTH) reaction offers an improvement over the reverse water-gas shift coupled with Fischer-Tropsch synthesis reaction (RWGS-FTS), as it is not limited by Anderson-Schulz-Flory distribution and yields higher selectivity towards specific products (e.g., olefins, aromatics, higher hydrocarbons). Herein, we focus on the recent progress achieved through this pathway and outline the existing knowledge gaps. We discuss the challenges involved in the process and highlight the key descriptors in the selection of catalyst components. Finally, we present several potential solutions to circumvent the current challenges, aiming to expedite the advancement of this route toward an efficient CO 2 hydrogenation process.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Ultrasmall Cu Nanoparticles Supported on Crystalline, Mesoporous ZnO for Selective CO 2 Hydrogenation

Converting CO 2 to value-added chemicals, e. g., CH 3 OH, is highly desirable in terms of the carbon cycling while reducing CO 2 emission from fossil fuel combustion. Cu-based nanocatalysts are among the most efficient for selective CO 2 -to-CH 3 OH transformation; this conversion, however, suffers from low reactivity especially in the thermodynamically favored low temperature range. We herein report ultrasmall copper (Cu) nanocatalysts supported on crystalline, mesoporous zinc oxide nanoplate (Cu@mZnO) with notable activity and selectivity of CO 2 -to-CH 3 OH in the low temperature range of 200–250 °C. Cu@mZnO nanoplates are prepared based on the crystal-crystal transition of mixed Cu and Zn basic carbonates to mesoporous metal oxides and subsequent hydrogen reduction. Under the nanoconfinement of mesopores in crystalline ZnO frameworks, ultrasmall Cu nanoparticles with an average diameter of 2.5 nm are produced. Cu@mZnO catalysts have a peak CH 3 OH formation rate of 1.13 mol h −1 per 1 kg under ambient pressure at 246 °C, about 25 °C lower as compared to that of the benchmark catalyst of Cu−Zn−Al oxides. In conclusion, our new synthetic strategy sheds some valuable insights into the design of porous catalysts for the important conversion of CO 2 -to-CH 3 OH.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2014

Carbon-Fuelled Future

Whether due to changes in policy or consumption of available fossil fuels, alternative sources of energy will be required, especially given the rising global energy demand. However, one of the main factors limiting the widespread utilization of renewable energy, such as wind, solar, wave or geothermal, is our ability to store energy. Storage of energy from carbon-neutral sources, such as electricity from solar or wind, can be accomplished through many routes. One approach is to store energy in the form of chemical bonds, as fuels. The conversion of low-energy compounds, such as water and carbon dioxide, to higher energy molecules, such as hydrogen or carbon-based fuels, enables the storage of carbon-neutral energy on a very large scale. The author¹s work in this area is supported by the US Department of Energy Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

CO2 reduction renewable energy↗
DOE OSTI2015

Selective Formation of Indene through the Reaction of Benzyl Radicals with Acetylene

The combustion of fossil fuels forms polycyclic aromatic hydrocarbons (PAHs) composed of five- and six- membered aromatic rings, such as indene (C 9 H 8 ), which are carcinogenic, mutagenic, and deleterious to the environment. Indene, the simplest PAH with single five- and six-membered rings, has been predicted theoretically to be formed through the reaction of benzyl radicals with acetylene. Benzyl radicals are found in significant concentrations in combustion flames, owing to their highly stable aromatic and resonantly stabilized free-radical character. We provide compelling experimental evidence that indene is synthesized through the reaction of the benzyl radical (C 7 H 7 ) with acetylene (C 2 H 2 ) under combustion-like conditions at 600 K. The mechanism involves an initial addition step followed by cyclization and aromatization through atomic hydrogen loss. This reaction was found to form the indene isomer exclusively, which, in conjunction with the high concentrations of benzyl and acetylene in combustion environments, indicates that this pathway is the predominant route to synthesize the prototypical five- and six-membered PAH.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Synchrotron Photoionization Study of the Diisopropyl Ether Oxidation

Abstract Scientific evidence has shown oxygenates help to reduce dangerous pollutants arising from burning fossil fuel in the automotive sector. For this reason, their use as additives has spread widely. The aim of this work consists in providing a comprehensive identification of the main primary oxidation products of diisopropyl ether (DIPE), one of the most promising among etheric oxygenates. The Cl‐initiated oxidation of DIPE is examinated by using a vacuum ultraviolet (VUV) synchrotron radiation at the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory (LBNL). Products are identified on the basis of their mass‐to‐charge ratio, shape of photoionization spectra, adiabatic ionization energies, and chemical kinetic profiles, at three different temperatures (298, 550, and 650 K). Acetone, propanal, propene, and isopropyl acetate have been identified as major reaction products. Acetone is the main primary product. Theoretical calculations using the composite CBS‐QB3 method provided useful tools to validate the postulated reaction mechanisms leading to experimentally observed species. The formation of other species is also discussed.

Giustini, Andrea↗
DOE OSTI2025

Understanding the Active Site Structures and Achieving Catalytic Activity Tuning of Atomically Dispersed FeN 4 Sites for Oxygen Reduction Reaction

Atomically dispersed Fe–—N—C catalysts with high oxygen reduction reaction (ORR) activity have attracted great attention since the last decade. Due to comparable ORR activity and low material cost, they are promising platinum group metal (PGM)-free catalysts that can replace the commercialized Pt/C materials; furthermore, it can facilitate the efficiency of the fuel cell technologies and mitigate dependence on fossil fuels. Great advancements have been made to experimentally optimize the synthesis approach of the Fe–—N—C catalysts, enhance the ORR activity, and improve the catalyst stability. Similarly, recent theoretical studies also provide enriched understanding of the active site structures, properties, and reaction mechanisms. In this review, discussions are made upon utilizing combined experimental and computational spectroscopy to reveal the active site structures, employing mechanistic studies to investigate reaction thermodynamics and kinetics, as well as developing scaling relationships to assist the design and development of future PGM-free catalyst materials. Furthermore, recent advances in studying Fe–—N—C catalysts utilizing electrified surface models and explicit solvation models are also discussed. Not only can these aspects improve the accuracy of theoretical simulation and predictions but also deepen the understanding of the catalyst properties and reaction mechanisms under the effect of surface charges and solvent molecules.

Fe single-atom catalysts↗
DOE OSTI2024

Membrane Separations in Biomass Processing

The development of integrated biorefineries and the greater utilization of biomass resources to reduce dependence on fossil fuel-derived products require research emphasis not just on conversion strategies but also on improving separations associated with biorefining. A significant roadblock towards developing biorefineries is the lack of effective separation techniques evidenced by the relative deficiency of literature in this area. Additionally, high conversion yields may only be realized if effective separations generate feedstock of sufficient purity – this makes research into biomass conversion strategies all the more critical. In this review, the challenges associated with biomass separations are discussed, followed by an overview of the most appropriate separation strategies for processing biomass. One of the unit operations most appealing for biorefining, membrane separations (MS), is then considered along with a review of the recent literature utilizing this technique in biomass processing.

09 BIOMASS FUELS↗
DOE OSTI2023

Identifying biomass yield potential of tetra, hexa, and octoploid prairie cordgrass populations grown on marginal lands

As the demand for renewable energy sources with reduced carbon emissions to the atmosphere increases, bioenergy crops remain an attractive alternative to fossil fuels. Another appeal of bioenergy crops is the potential utilization of marginal lands not suitable for food crops. Prairie cordgrass is a perennial warm season polyploid grass species being considered as a bioenergy crop that also exhibits a high tolerance for salinity and flooding. The ploidy level of prairie cordgrass has previously been suggested to correlate with agronomic traits. However, little is known about the agricultural performance of prairie cordgrass on marginal lands and if a correlation of ploidy level to stress tolerance exists. In this experiment, the productivity of tetraploids, hexaploids, and octoploids was investigated when grown on three different marginal sites including waterlogged, saline, and low-nutrient gravelly soils. Here we found that prairie cordgrass populations annually produced dry biomass on a wet marginal site comparable to normal cropland. However, the productivity was remarkedly decreased at both a salt-affected site and a limestone mine reclamation site. We were unable to conclude that different ploidy levels affected the biomass yield of prairie cordgrass grown under abiotic stress. However, there was a differential response of populations to various types of marginal sites. Finally, these results indicate potential genetic resources for developing breeding targets and identifying mechanisms of abiotic stress tolerance. Moreover, we highlight the need to generate diverse ploidy levels of prairie cordgrass in the same genetic backgrounds for future testing.

09 BIOMASS FUELS↗
DOE OSTI2016

The Effect of Functional Groups in Bio-Derived Fuel Candidates

Interest in developing renewable fuels is continuing to grow and biomass represents a viable source of renewable carbon with which to replace fossil-based components in transportation fuels. During our own work, we noticed that chemists think in terms of functional groups whereas fuel engineers think in terms of physical fuel properties. In this Concept article, we discuss the effect of carbon and oxygen functional groups on potential fuel properties. This serves as a way of informing our own thinking and provides us with a basis with which to design and synthesize molecules from biomass that could provide useful transportation fuels.

09 BIOMASS FUELS↗
DOE OSTI2017

Artificial Photosynthesis: Beyond Mimicking Nature

In this Editorial, Guest Editors Holger Dau, Etsuko Fujita, and Licheng Sun introduce the Special Issue of ChemSusChem on “Artificial Photosynthesis for Sustainable Fuels”. Here, they discuss the need for non-fossil based fuels, introduce both biological and artificial photosynthesis, and outline various important concepts in artificial photosynthesis, including molecular and solid-state catalysts for water oxidation and hydrogen evolution, catalytic CO 2 reduction, and photoelectrochemical systems.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Integrated Capture and Conversion of CO 2 to Methane Using a Water-lean, Post-Combustion CO 2 Capture Solvent

Integrated Carbon Capture and Conversion of CO 2 into materials (IC3M) is an attractive solution to meet the global energy demand, reduce our dependence on fossil fuels and lower CO 2 emissions. In this work, using a water-lean post combustion capture solvent, (N-(2-ethoxyethyl)-3-morpholinopropan-1-amine) (2-EEMPA), >90% conversion of captured CO2 to hydrocarbons, mostly methane, is achieved in the presence of a heterogenous Ru catalysts under relatively mild reaction conditions (170 °C and <15 bar H 2 pressure). The catalytic performance was better in 2-EEMPA than aqueous 5M monoethanol amine (MEA). Operando NMR study showed in-situ formation of N-formamide intermediate, which underwent further hydrogenation to form methane and other higher hydrocarbons. The technoeconomic analyses (TEA) showed that the proposed integrated process can potentially improve the thermal efficiency by 5% and reduce the total capital investment and minimum synthetic natural gas (SNG) selling price by 32% and 12% respectively compared to conventional Sabatier process, highlighting the energetic and economic benefits of integrated capture and conversion. Methane derived from CO 2 and renewable H 2 source is an attractive fuel, and it has a great potential as a renewable hydrogen carrier as an environmentally responsible carbon capture and utilization approach.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗