Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “glycolization”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

In-Process Melt Separation of Depolymerized PET in PET/PE Blends for Upcycling via Twin-Screw Extrusion

Our previous work focused on depolymerizing polyethylene terephthalate (PET) in twin-screw extrusion, as part of a broader project to continuously separate PET from polyolefins in the melt. This study focused on linear low-density polyethylene (LLDPE) and PET films and the use of ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), and bis(2-hydroxyethyl) terephthalate (BHET) to depolymerize the PET in the extruder to levels above 90% Mw. In this work, the focus will shift to achieving separation of the two polymers in the twin-screw extruder, which is made possible due to a 90% reduction in the Mw of the PET, which caused a decrease of its viscosity by several orders of magnitude. Owing to the viscosity difference and pressure buildup in the die, the low-viscosity PET preferentially exited a degassing vent instead of going through the die. This is because the flow of the PET would travel through a non-pressure vent rather than through a high-pressure die. However, owing to the higher viscosity of the LLDPE, the pressure was too high to pass through such a small diameter vent hole. Supercritical CO 2 (SCCO 2 ) was used to assist in this extraction, but SCCO 2 negatively impacted the overall degree of separation. Through analysis of the separated materials, it was concluded that a high separation of the two materials was achieved. TGA and FTIR confirmed that the material separated from the vent was 100% PET. The material removed from the die was composed of 95% LLDPE and 5% PET.

36 MATERIALS SCIENCE↗
DOE OSTI2026

In‐Process Melt Separation of PE/PET Blends for Upcycling via Twin‐Screw Extrusion. Impact of Catalyst Reagents on PET Depolymerization

Part 1 of this work focused on depolymerizing polyethylene terephthalate (PET) in twin-screw extrusion, as part of a broader project to continuously separate PET from polyolefins in the melt. This study focused on linear low-density polyethylene (LLDPE) and PET films and the use of ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), and bis(2-hydroxyethyl) terephthalate (BHET) to depolymerize the PET in the extruder to levels above 90% Mw. In part 2, the focus will shift to achieving separation of the two polymers in the twin-screw extruder, which is made possible due to a 90% reduction in the Mw of the PET, which caused a decrease of its viscosity by several orders of magnitude. Owing to the viscosity difference and pressure buildup in the die, the low-viscosity PET preferentially exited a degassing vent instead of going through the die. This is because the flow of the PET would travel through a non-pressure vent rather than through a high-pressure die. However, owing to the higher viscosity of the LLDPE, the pressure was too high to pass through such a small diameter vent hole. Supercritical CO₂ (SCCO₂) was used to assist in this extraction, but SCCO₂ negatively impacted the overall degree of separation. Through analysis of the separated materials, it was concluded that a very high separation of the two materials was achieved. TGA and FTIR confirmed that the material separated from the vent was 100% PET. The material removed from the die was composed of 90% LLDPE and 10% PET.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Catalase protects against nonenzymatic decarboxylations during photorespiration in Arabidopsis thaliana

Abstract Photorespiration recovers carbon that would be otherwise lost following the oxygenation reaction of rubisco and production of glycolate. Photorespiration is essential in plants and recycles glycolate into usable metabolic products through reactions spanning the chloroplast, mitochondrion, and peroxisome. Catalase in peroxisomes plays an important role in this process by disproportionating H 2 O 2 resulting from glycolate oxidation into O 2 and water. We hypothesize that catalase in the peroxisome also protects against nonenzymatic decarboxylations between hydrogen peroxide and photorespiratory intermediates (glyoxylate and/or hydroxypyruvate). We test this hypothesis by detailed gas exchange and biochemical analysis of Arabidopsis thaliana mutants lacking peroxisomal catalase. Our results strongly support this hypothesis, with catalase mutants showing gas exchange evidence for an increased stoichiometry of CO 2 release from photorespiration, specifically an increase in the CO 2 compensation point, a photorespiratory‐dependent decrease in the quantum efficiency of CO 2 assimilation, increase in the 12 CO 2 released in a 13 CO 2 background, and an increase in the postillumination CO 2 burst. Further metabolic evidence suggests this excess CO 2 release occurred via the nonenzymatic decarboxylation of hydroxypyruvate. Specifically, the catalase mutant showed an accumulation of photorespiratory intermediates during a transient increase in rubisco oxygenation consistent with this hypothesis. Additionally, end products of alternative hypotheses explaining this excess release were similar between wild type and catalase mutants. Furthermore, the calculated rate of hydroxypyruvate decarboxylation in catalase mutant is much higher than that of glyoxylate decarboxylation. This work provides evidence that these nonenzymatic decarboxylation reactions, predominately hydroxypyruvate decarboxylation, can occur in vivo when photorespiratory metabolism is genetically disrupted.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2025

Tunable Crosslinked Ether Polymer Network Electrolytes for High‐Performance All‐Solid‐State Sodium Batteries

All-solid-state batteries (ASSBs) are critical for achieving high energy density and enhanced safety. Solid polymer electrolytes (SPEs) offer key advantages over other electrolytes, including improved safety, flexibility, and interfacial contact. Among the SPEs, ether-based polymers are widely studied due to their ease of processing and high ionic conductivity (σi) in the amorphous state. In this work, the introduction of poly(ethylene glycol) methyl ether methacrylate (PEGMEMA) into an SPE matrix composed of poly(ethylene glycol) diacrylate (PEGDA), poly(ethylene glycol) (PEG2k), and sodium bis(fluorosulfonyl)imide (NaFSI) salt is investigated to facilitate the formation of amorphous, high σ i SPEs through end-group engineering and polymer ratio optimization. PEGMEMA enhances structural integrity via crosslinking with PEGDA through its methacrylate group, while its methyl end group aids ion conduction. A 2:1:7 ratio of PEGDA:PEGMEMA:PEG2k exhibits a σi of 1.16 x 10 -4 S cm -1 and oxidative stability up to 4.4 V at 60 °C. A solid-state cell incorporating this SPE, a Na 2/3 Ni 1/3 Mn 2/3 O 2 (NM12) cathode, and a sodium-metal anode demonstrates excellent cycling stability, retaining over 80 % of its initial capacity for 150 cycles at 60 °C. The findings highlight the potential of end-group engineering in improving the electrochemical performance of SPEs.

25 ENERGY STORAGE↗
DOE OSTI2020

Goldilocks and the three glymes: How Na+ solvation controls Na–O 2 battery cycling

In this work we report a framework to understand the role of solvent-salt interactions and how they mediate the performance of sodium-air/O 2 batteries. The utilization of suitable electrolyte materials remains a point of major concern within the research community, as their stability and decomposition pathways during cycling are intimately connected with capacity and cycle life. Glyme based solvents have been widely utilized in Na–O 2 batteries, however, to date no clear correlation between solvent/electrolyte properties and battery performance has been given. Herein, we have examined the effect of glyme chain length (ethylene glycol dimethyl ether DME; diethylene glycol dimethyl ether, DEGDME; and tetraethylene glycol dimethyl ether, TEGME) on the cycling behaviour of Na–O 2 batteries and conclude that overall cell performance is highly dependent on solvent selection, salt concentration and rate of discharge/charge. We demonstrate how solvent selection helps define cell chemistry and performance by linking salt-solvent interactions to enthalpy of dissolution - and subsequently to sodium battery electrolyte properties - through the combination of both experimental and theoretical methodologies. The approaches detailed in this study could be used to predictively prepare electrolytes for Li-air batteries, other glyme-based electrochemical systems and low temperature applications.

25 ENERGY STORAGE↗
DOE OSTI2026

The effect of hydroxyl spacing in diols on the solvation structure, dynamics, and transport properties of choline chloride-based deep eutectic solvents

Deep eutectic solvents (DESs) are a class of liquids that offer great potential in alleviating some of the challenges present in today's long-term energy storage methods because they have physical properties that are favorable for storable electrolyte solutions. In this work, a series of glycols (ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,5-pentanediol) were studied as potential hydrogen bond donors (HBD) with a common choline chloride (ChCl) as the hydrogen bond acceptor (HBA). The solvation dynamics of the prepared systems were studied by measuring the solvent reorganization response using femtosecond transient absorption spectroscopy (fs-TA). Conductivity, viscosity, density, ET(30) polarity, and dynamics of the prepared DESs were analyzed, with a particular interest in determining the effect of HBD chain length on these parameters. Here, classical molecular dynamics simulations were employed to investigate how the local liquid structure, solvent dynamics, and bulk solvent properties vary with changes in glycol chain length.

Conductivity↗
DOE OSTI2025

Understanding the impact of SPMAK and PEGPEA in crosslinked PEGDA membranes: Methanol-carboxylate co-transport behavior and correlating structure-physicochemical-transport properties

Investigating multicomponent transport in dense, hydrated polymer membranes is necessary in applications such as fuel cells, electrolyzers, and desalination systems. Of particular interest are photoelectrochemical CO 2 reduction cells (PEC-CRC) which produce liquid products such as alcohols (methanol) and carboxylates (formate, acetate). Flux coupling and competitive sorption behavior of these products (solutes) have been found to affect permselectivity, thereby motivating us to investigate fundamental membrane structure-physicochemical-transport relationships. Past research has shown that systematic tuning of crosslinked cation exchange membranes (CEMs) with charge-neutral monoacrylate monomers containing alkyl and phenyl groups (i.e., poly(ethylene glycol) methacrylate (PEGMA), and poly(ethylene glycol) phenyl ether acrylate (PEGPEA)) can suppress acetate transport (permeability) in co-permeation with methanol. To further investigate this transport behavior and to enhance membrane ionic conductivities, 3-sulfopropyl methacrylate potassium (SPMAK), a sulfonated monoacrylate monomer is incorporated here. SPMAK content is varied with neutral PEGPEA and diacrylate crosslinker, poly (ethylene glycol) diacrylate (PEGDA) of two different chain lengths (n = 10 and 13) to prepare membranes of various compositions. Electrochemical and physicochemical properties including ionic conductivity, ion exchange capacity, and water uptake increase with increasing charged SPMAK content. Different states of water within hydrated membranes are probed using differential scanning calorimetry (DSC), where increasing intermediate (loosely bound) water is observed with increasing hydrophilic SPMAK content. The transport behavior of methanol and carboxylates (formate, acetate, propionate) are investigated, where permeabilities vary as methanol > formate > acetate ≈ propionate. Interestingly, permeabilities decrease with increasing PEGPEA content and are more dependent on solute diffusion than sorption. Permeabilities and diffusivities decrease while permselectivities increase with decreasing PEGDA chain length.

25 ENERGY STORAGE↗
DOE OSTI2024

Sub-Ambient Performance of Potassium Sarcosinate for Direct Air Capture Applications: CO 2 Flux and Viscosity Measurements

Absorption based direct air capture (DAC) technologies have garnered significant interest in recent years due to their scalability, competitive regeneration energy requirements, and low susceptibility to degradation. One of the key advantages of DAC lies in its flexible siting options and the potential to utilize low-value land. However, most of the research in this field has been focused on ambient climate zones (T > 20 °C), overlooking sub-ambient (–30 °C < T < 20 °C) regions, which comprise approximately 70 % of the Earth’s surface. To fully realize the potential of DAC, it is essential to understand how DAC solvents perform in these sub-ambient conditions before any large-scale deployment can be considered. Among DAC solvents of interest, potassium sarcosinate (K-SAR) has emerged as a promising candidate due to its high CO 2 capacity, fast uptake kinetics, compatibility with contactor packing materials, low volatility, good thermal and oxidative stability, and competitive regeneration energy requirements compared to current industry standards. This paper characterizes the CO 2 flux and viscosity of K-SAR at sub-ambient conditions and explores the potential of using ethylene glycol and triethylene glycol as additives to prevent solvent freezing in DAC applications. For 1 M K-SAR, the CO 2 flux ranges between 1.3 × 10 -5 and 8.0 × 10 -5 mol m –2 s –1 across a temperature range of –5 °C to 45 °C. Ethylene glycol is shown to effectively suppress the freezing point of K-SAR below –30 °C with volumetric loadings of the additive as low as 0.1. Here, a reaction model was developed to predict the CO 2 flux for 1 M K-SAR at different temperatures, demonstrating good agreement between experimental and theoretical fluxes.

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

Simple but tricky: Investigations of terephthalic acid purity obtained from mixed PET waste

In this study, we report for the first time, the basic depolymerization of mixed waste-polyethylene terephthalate (PET) by hydrolysis and subsequent terephthalic acid monomer recovery at high purity using benign reaction conditions. Several conditions were tested for depolymerization such as PET chips size, concentration of aqueous sodium hydroxide (20 or 30%), organic co-solvent (ethylene glycol or ethanol), temperature at which the reaction was run and duration of the heating. More importantly, several batches of PET were utilized as starting materials including a commercial PET, chopped PET obtained from clean bottles whose caps and labels were removed and the purity of the product from each condition was evaluated via nuclear magnetic resonance (1HNMR and 13CNMR), differential scanning calorimetry (DSC) and powder Xray diffraction (XRD). Unsurprisingly, the conversion of PET is dependent on the particle size varying from 100% conversion for fine powder to 73% conversion for (300 µm, mesh 6 – 20 or mesh 14-20). Ethanol appears to be more efficient as a co-solvent than ethylene glycol, with higher PET depolymerization conversions (94% versus 75-80%), shorter reaction times (2h versus 6h) and lower temperatures (80 °C versus 110 °C). The terephthalic acid (TPA) recovered appeared to have only subtle differences among the batches, most notably a pink color when the reaction was run in ethanol/base. The DSC of the compounds produced in ethylene glycol water appear to display a melting point (280-288 °C) while the samples prepared in ethanol as well as a commercial sample did not. Overall, the purity of the various TPA batches is comparable, and similar to commercial TPA, demonstrating the utility of the method to depolymerize realistic waste streams. The method is simple, demonstrated on multigram scale (15-30g) and allows for the complete removal of waste other than PET unaffected by alkaline conditions.

Cosimbescu, Lelia↗
DOE OSTI2022

Self-Assembly of Partially Charged Diblock Copolymer-Homopolymer Ternary Blends

Ternary blends comprising of a diblock copolymer and the corresponding homopolymers provide ready access to a variety of morphologies, but the impact of charge on their phase behavior has not been studied extensively. Here, three partially charged ternary blends consisting of symmetric poly[(oligo(ethylene glycol) methyl ether methacrylate-co-oligo(ethylene glycol) propyl sodium sulfonate methacrylate)] (POEGMA#), polystyrene (PS), and POEGMA#-PS with different charge fractions were prepared, where # denotes the mole fraction of charged monomers in the POEGMA chain. Here, the phase behavior was systematically studied using small-angle X-ray scattering (SAXS), and isothermal phase diagrams at 120 °C were constructed. The resulting isothermal planes contain a wide lamellar (LAM) phase window with a slight deviation from symmetry for ion-containing ternary blends, due to the homopolymer size difference. Given the absence of any significant change in the phase diagrams as the charge fraction increases, the role of charge is primarily to increase the segregation strength in the ternary system, as in the case of partially charged diblock polymers. In addition, examination of the increase in domain size along the volumetrically symmetric isopleth reveals a “dry-brush” like swelling behavior of homopolymers in all three blends, presumably due to the space-filling nature of the oligomeric ethylene glycol side chains on POEGMA.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2023

Impact of Hydrogen Bonds on CO 2 Binding in Eutectic Solvents: An Experimental and Computational Study toward Sorbent Design for CO 2 Capture

Choline-based amino acid ionic liquids with anions glycinate, β-alaninate, phenylalaninate, and prolinate were synthesized and mixed with ethylene glycol to form lower-viscosity benign eutectic solvents for CO 2 capture. The highest capacity measured was 0.7 moles of CO 2 per mole of ionic liquid (2 moles CO 2 per kg solvent) for a 1 to 2 mole ratio mixture of choline prolinate to ethylene glycol at 1 bar of CO 2 and 25 °C. Under 5000 ppm of CO 2 , half of this capacity was realized. Here, through a combined study of quantitative 13 C NMR spectroscopy, molecular dynamics simulations and density functional theory calculations, we show that hydrogen bonding in the eutectic solvent prevents proton-transfer between prolinate anions upon CO 2 absorption, which occurs in the absence of ethylene glycol and deactivates binding sites. Blocking this proton transfer leads to a higher binding capacity compared to neat choline prolinate. This work demonstrates the impact of hydrogen bonding on the CO 2 binding mechanism and energetics, as well as physical and thermal properties in eutectic solvents, thus addressing an unmet need and informing future studies on the development of benign sorbents for capturing CO 2 from dilute streams.

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

Upper critical solution temperature polymer assemblies via variable temperature liquid phase transmission electron microscopy and liquid resonant soft X-ray scattering

Abstract Here, we study the upper critical solution temperature triggered phase transition of thermally responsive poly(ethylene glycol)- block -poly(ethylene glycol) methyl ether acrylate- co -poly(ethylene glycol) phenyl ether acrylate- block -polystyrene nanoassemblies in isopropanol. To gain mechanistic insight into the organic solution-phase dynamics of the upper critical solution temperature polymer, we leverage variable temperature liquid-cell transmission electron microscopy correlated with variable temperature liquid resonant soft X-ray scattering. Heating above the upper critical solution temperature triggers a reduction in particle size and a morphological transition from a spherical core shell particle with a complex, multiphase core to a micelle with a uniform core and Gaussian polymer chains attached to the surface. These correlated solution phase methods, coupled with mass spectral validation and modeling, provide unique insight into these thermoresponsive materials. Moreover, we detail a generalizable workflow for studying complex, solution-phase nanomaterials via correlative methods.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

Solubility-limited depolymerization kinetics in the glycolysis of carbonyl-containing polymers

Chemical recycling of condensation polymers is often rationalized on the basis of the intrinsic reactivity of ester and carbonate functional groups. However, under heterogeneous conditions relevant to plastic waste processing and environmental degradation, bulk depolymerization rates often diverge from trends predicted by homogeneous chemistry. Here, we investigate how polymer–solvent compatibility, catalyst strength, and phase behavior govern the heterogeneous glycolysis of carbonyl-containing polymers. Using poly(ethylene terephthalate) (PET), glycol-modified PET (PETG), and bisphenol-A polycarbonate (PC) as model systems, we examine depolymerization kinetics at 180 °C with ethylene glycol and bisphenol A as diols under both amphoteric organosalt (TBD : MSA) and strong base (TBD) catalysis. Despite substantial differences in crystallinity and glycol uptake, PET and PETG depolymerize at comparable rates under organosalt catalysis, while PC depolymerizes significantly more slowly under identical conditions. Time-resolved molecular weight analysis and thermal characterization demonstrate that these rate differences do not arise from crystallinity, swelling, or inherent carbonyl reactivity, but instead reflect solubility-limited kinetics that constrain the transition from heterogeneous to homogeneous reaction regimes. When polymer solubility is low, depolymerization remains heterogeneous and slow; when solubility is enhanced—either through increased polymer–diol compatibility or stronger base catalysis—rapid homogeneous depolymerization is observed, reversing apparent reactivity trends. These results establish solubility and phase behavior as primary determinants of depolymerization kinetics in heterogeneous polymer recycling systems. By demonstrating how catalyst selection and solvent compatibility can expose or overcome solubility limitations, this work provides mechanistic insight to design more energy-efficient and selective chemical recycling processes. More broadly, these findings suggest that polymers with limited solvent or water compatibility may resist chemical degradation in the environment, favoring fragmentation and persistence as micro- and nanoplastics. Understanding solubility-controlled depolymerization offers a pathway toward more sustainable polymer design and end-of-life chemical recovery.

Watson-Sanders, Shelby [Department of Chemistry, U↗
DOE OSTI2021

Manipulating meso-scale solvent structure from Pd nanoparticle deposits in deep eutectic solvents

Deep Eutectic Solvents (DESs) are complex solutions that present unique challenges compared to traditional electrolytes. Unlike most electrolytes and ionic liquids, DESs have delicate hydrogen bond networks that are responsible for their highly sensitive compositional dependence on the melting point. Prior work has demonstrated unique nanoscale structure both experimentally and theoretically that brings both challenges and opportunities to their adoption in traditional electrochemical processes. In this study, we use in-situ sample-rotated ultra-small angle X-ray scattering to resolve the near-interface solvent structure after electrodepositing Pd nanoparticles onto a glassy carbon electrode in choline chloride:urea and choline chloride:ethylene glycol DESs. Our results indicate that solvent structure can be observed on the meso-scale in the choline chloride:urea and choline chloride:ethylene glycol systems. Importantly, this extended solvent structure peaks at -0.5 V (vs. Ag/AgCl) and decreases slightly with higher overpotentials during Pd electrodeposition. Experimentally, the nature of this structure is more pronounced in the ethylene glycol system, as evidenced by both the X-ray scattering as well as the electrochemical impedance spectroscopy (EIS). Here, molecular dynamics simulations and dipolar orientation analysis reveal that chloride delocalization near the Pd interface and long-range interactions between the choline and each hydrogen bond donor are very different and qualitatively consistent with the experimental data. These results show how the long-range solvent-deposit interactions can be tuned by changing the hydrogen bond donor in the DES and the applied potential.

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

Impact of Catalyst Ink Dispersing Solvent on PEM Fuel Cell Performance and Durability

The dispersing solvent used for fuel cell catalyst ink preparation plays a vital role in establishing the resulting morphology of the electrode layers, which in turn will impact the performance of proton exchange membrane (PEM) fuel cells. In this study, we report the impact of various ionomer dispersion solvents on PEM fuel cell performance and durability; two aqueous (1-propanol/water and 2-propanol/water) and several non-aqueous dispersing solvents (ethylene glycol and 1,2-butanediol) are compared. The cathode catalyst layer (CCL) fabricated using inks prepared with 1-propanol/water (3:1, w/w) exhibited the best initial performance followed by the CCL prepared using ethylene glycol. The CCLs made from non-aqueous ethylene glycol and 1,2-butanediol exhibited the best durability upon accelerated stress testing. Scanning transmission electron microscopy combined with energy dispersive X-ray spectroscopy indicated that, after the stress test, the distribution of both the Nafion ionomer and Pt nanoparticles within the CCLs prepared with non-aqueous ionomer dispersions underwent less change than those prepared with aqueous dispersions, which is responsible for the improved durability

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

Optimization of DARHT Axis 1 Injector Voltage

The Dual-Axis Radiographic Hydrodynamic Test (DARHT) facility provides flash radiography capabilities using two electron Linear Induction Accelerators (LIA’s). Axis-1 of DARHT produces a 20- MeV, 2-kA, 80-ns-FWHM electron beam. The strict requirements for flash radiography require a detailed understanding of the LIA’s performance, including precision measurements of the injector electron beam energy. The technique for time resolved measurement of the electron beam energy using electron Permanent Magnet Spectrometer (ePMSpec) has been developed. The electron energy then is used to infer the voltage produced by the injector pulsed power. The injector pulsed power of DARHT I consists of a 1.5-MV, glycol-insulated Blumlein that is pulsecharged by a step-up transformer and switched by four, laser-triggered spark gaps. A series of increasing impedance transmission lines are used to transform the output voltage of the Blumlein to a maximum of 3.8MV at the diode. Figure 1a shows a graphic of the Axis-1 prime power tank, Blumlein and downstream transmission lines. The injector pulse power is designed to produce voltage on a velvet cathode located in the vacuum vessel. The specifications of the voltage-pulse flat-top over 60ns is +/-1%. A key element in the high-voltage circuit is the ethylene glycol Blumlein. The outer volume, adjacent to the laser triggered switches of the Blumlein, is a peaking capacitor. This is an independent volume that contains a mixture of ethylene glycol and water to make it an adjustable capacitor of 380 to 750 pF.

43 PARTICLE ACCELERATORS↗
DOE OSTI2022

Evaluation of Sludge Solids Returns Impacts on Sludge Batch 10 Flammability, Glass Quality, and Glass Processability

The Savannah River National Laboratory (SRNL) is currently preparing to return ≤ 20 kgs of sludge solids collected over time from Tank Farm characterization activities and demonstrations of the Defense Waste Processing Facility (DWPF) flowsheets (nitric-formic and nitric-glycolic). These sludge solids will be transported and added to Tank 51 which is currently preparing Sludge Batch (SB) 10. DWPF plans to operate the under the nitric-glycolic flowsheet for the processing of SB10. The hydrogen generation rate for the nitric-glycolic flowsheet is 0.024 lb h -1 . The addition of ≤20 kg of sludge solids returns to SB 10 does not have an impact on flammability in the DWPF Chemical Process Cell (CPC) or glass quality and processability. The relatively low mass of the addition (≤20 kg) is insufficient to detect a significant analytical change to the expected SB 10 compositions.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2026

Effect of H 2 O on the ethylene glycol/alkali dismantling of bagasse for high-value conversion

Using a high-boiling alcohol system to dismantle main components of biomass is a feasible technology. Reducing dismantle operating costs and improving dismantle efficiency are essential for promoting the green, economical, and sustainable development of biomass refining. Therefore, based on the low cost and chemical properties of H 2 O at high temperature, the effects of different H 2 O dosages in NaOH-catalyzed ethylene glycol (HBAA) system on the dismantling efficiency of bagasse, surface lignin coverage, recovered-lignin activity and enzymatic hydrolysis efficiency were investigated. Compared with the HBAA dismantling system without H 2 O, the HBAA system with 60% w/v H 2 O can obviously increase the removal rates of lignin and hemicellulose, while recovering up to 99% of cellulose and significantly declining surface lignin coverage, thus enhancing the enzymatic hydrolysis efficiency. Additionally, the results of density functional theory calculations and 2D HSQC NMR analysis prove that the synergy between H 2 O and ethylene glycol can promote the esterification reaction occurrence at the α-C carbon cation in β-O-4 structure of lignin, thereby protecting the β-O-4 aromatic ether bond. Simultaneously, when the H 2 O dosage increase from 0% to 60%, the enzymatic yield increases from 84.51% to 93.74% with an enzyme load of 10 FPU/g. Based on experimental results, this study conducted a techno-economic analysis of bagasse dismantling for ethanol and co-production of lignin, achieving a minimum ethanol selling price of $\$$1.07 per kg. Here, in this study, a green and economical solution for dismantling the main components of bagasse is developed, which is important for the high-value conversion of bagasse.

Ethylene glycol↗