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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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At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Evaluating the Physisorption and Chemisorption of Iodine on Bismuth-Functionalized Carbon Foams

Bismuth-containing carbon materials have been shown to be highly promising sorbents for the capture of radioiodine. However, there is still a need to understand the effects of carbon and bismuth on the iodine sorption mechanism. In this study, we show the relationship between the physical and chemical sorption of iodine under different bismuth loading conditions. Here, highly porous and non-friable conductive carbon foams were prepared and bismuth was electrodeposited to provide strong iodine binding sites. For pure carbon foams, equal ratios of physisorbed and chemisorbed iodine-carbon phases were detected before desorption. As the concentration of bismuth increased, the chemisorption between bismuth and iodine dominated the total capture mechanism and physisorption was almost completely eliminated. Additionally, chemisorption of iodine depended upon the size and specific surface area of the bismuth particles present within the framework of the foam.

36 MATERIALS SCIENCE↗
DOE OSTI2023

From ash to oxides: Recovery of rare-earth elements as a step towards valorization of coal fly ash waste

Coal fly ash (CFA) is both a valuable waste material and a potential source of environmental contamination. The inclusion of metals such as rare-earth elements offer a possible incentive towards waste valorization if the metals can be extracted and recovered in an economical manner. Rare-earth elements (REEs) have many technological applications and are critically important in the manufacture of electric vehicles, communication devices, and industrial magnets. However, the global supply of rare-earth elements has faced shortages and price shocks. Current methods for separating and isolating individual rare-earth elements use large amounts of energy and organic solvents, raising concerns over environmental impacts. These factors have led to the investigation of nontraditional sources and separation techniques for these elements. Here, we describe a column-based system that uses a newly developed ligand-associated organosilica sorbent to concentrate and separate rare-earth elements from fly ash leachate. The fly ash used in this study originally contained 0.024 wt% rare-earth elements and the final oxide powder after enrichment contained > 10 wt% rare-earth elements, which is a enrichment of > 400 times. This process requires no additional organic solvents after the sorbent media has been synthesized, offering an alternative to the current standard using solvent extraction for rare-earth element recovery.

42 ENGINEERING↗
DOE OSTI2025

Self-Supported Branched Poly(ethylenimine) Monoliths from Inverse Template 3D Printing for Direct Air Capture

3D-printed inverse templates are combined with ice templating to develop self-supported branched poly(ethylenimine) monoliths with regular channels of varying channel density and ordered macropores. A maximum uptake of 0.96 mmol of CO 2 /g of monolith from ambient air containing 45.5% RH is achieved from dynamic breakthrough experiments, which is a 31% increase compared to the CO 2 uptake from adsorption under dry conditions for the same duration. The breakthrough experiments show characteristics of internal mass-transfer limitations. The cyclic dynamic breakthrough experiments indicate stable operation without significant loss in CO 2 uptake across eight cycles. Moreover, the self-supported monolith shows minimal loss in adsorption capacity (7.7%) upon exposure to air containing 21% oxygen at 110 °C, in comparison to a conventional sorbent consisting of poly(ethylenimine) impregnated on Al 2 O 3 (18.9%). The monoliths exhibit good mechanical stability, contributed by elastic deformation, corresponding to up to 74% strain and lower pressure drop compared to many existing monoliths in the literature.

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

Iodine Sorption on AgZ-PAN

The Department of Energy (DOE) Nuclear Fuel Cycle and Supply Chain Program Material Recovery and Waste Form Development (MRWFD) Campaign Off-gas Sigma Team has performed research and development on iodine control and iodine waste forms for the past several years. This research and development has included iodine adsorption tests using a laboratory-scale test system containing multiple-segmented fixed beds of iodine adsorbents. Iodine capture performance has been tested using (a) non-radioactive synthetic gas mixtures blended from air, nitrogen, NO, NO 2 , water, to simulate dissolver off-gas (DOG) and vessel off-gas (VOG) streams from used nuclear fuel aqueous reprocessing, (b) inorganic and organic iodine species, and (c) different sorbents. An initial test of silver-functionalized mordenite in polyacrylonitrile matrix (AgZ-PAN) was conducted to assess if this sorbent, initially designed for selective sorption of Xe that evolves into used fuel reprocessing off-gas streams, could also be a candidate for iodine sorption. This test was conducted using the same deep-bed test system and methodologies used in many prior iodine sorption tests using other sorbents. Diatomic iodine (I2) was used as the target iodide in a gas stream containing air, NO, NO 2 , and moisture designed to simulate an aqueous reprocessing dissolver off-gas (DOG) stream.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2025

Frontiers of Ionic Liquids in Carbon Dioxide Separation and Valorization

Ionic liquids (ILs) have emerged as highly tunable sorbents and membranes for gas separation, especially in the purification of CO 2 -containing gas streams such as air, natural gas, biogas, and syngas. Their negligible volatility, high thermal stability, and chemical versatility position them as promising alternatives to conventional amine and alkaline metal derivative-based systems, effectively addressing key challenges such as volatility, stability, and high regeneration energy. Here, this Review explores IL-derived systems for CO 2 -related gas separation across dense, porous, and supported categories. At the dense liquid level, we discuss strategies for tailoring IL properties to optimize CO 2 sorption, focusing on the correlation between IL-CO 2 interaction strength, uptake capacity, and regeneration energy. Key advancements in carbon capture, including amino-functionalized (AILs) and superbase-derived ILs (SILs), are highlighted, along with strategies such as chemical structure engineering, multiple binding site integration, alternative driving force exploration, and stability enhancement. Then, the porous liquids (PLs) scale focuses on the emerging field integrating IL properties with permanent porosity engineering, spanning ultramicropores (<5 Å) to macropores (around 100 nm). These innovations improve gas uptake capacity, accelerate transport kinetics, introduce the gating effect, and enable the coexistence of active sites with antagonistic properties within a single IL medium. At the supported IL scale, the discussion shifts to IL- and ionic pair-modified sorbents and membranes, emphasizing the modulation of cations and anions, confinement effects from porous supports, and the IL–interface interaction to enhance CO 2 separation performance, particularly in diluted gas streams. Beyond separation, this Review highlights IL-based integrated processes for CO 2 capture and conversion into value-added chemicals via thermocatalytic, electrocatalytic, and photocatalytic pathways. At each scale, advanced computational and experimental tools for IL design are also discussed, providing insights into stability enhancement, sorption efficiency, and process integration. The Review concludes by addressing existing challenges and outlining future directions for IL-driven innovations in gas separation technologies.

Qiu, Liqi [Univ. of Tennessee, Knoxville, TN (Unit↗
DOE OSTI2022

Direct Observation of Ammonia Storage in UiO-66 Incorporating Cu(II) Binding Sites

The presence of active sites in metal–organic framework (MOF) materials can control and affect their performance significantly in adsorption and catalysis. However, revealing the interactions between the substrate and active sites in MOFs at atomic precision remains a challenging task. Here, we report the direct observation of binding of NH 3 in a series of UiO-66 materials containing atomically dispersed defects and open Cu(I) and Cu(II) sites. While all MOFs in this series exhibit similar surface areas (1111–1135 m 2 g –1 ), decoration of the -OH site in UiO-66-defect with Cu(II) results in a 43% enhancement of the isothermal uptake of NH 3 at 273 K and 1.0 bar from 11.8 in UiO-66-defect to 16.9 mmol g –1 in UiO-66-Cu II . A 100% enhancement of dynamic adsorption of NH 3 at a concentration level of 630 ppm from 2.07 mmol g –1 in UiO-66-defect to 4.15 mmol g –1 in UiO-66-Cu II at 298 K is observed. In situ neutron powder diffraction, inelastic neutron scattering, and electron paramagnetic resonance, solid-state nuclear magnetic resonance, and infrared spectroscopies, coupled with modeling reveal that the enhanced NH 3 uptake in UiO-66-Cu II originates from a {Cu(II)···NH 3 } interaction, with a reversible change in geometry at Cu(II) from near-linear to trigonal coordination. This work represents the first example of structural elucidation of NH 3 binding in MOFs containing open metal sites and will inform the design of new efficient MOF sorbents by targeted control of active sites for NH 3 capture and storage.

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

A Transferable Force Field for Simulating Adsorption in Metal–Organic Frameworks with Open Metal Sites Based on the 12–6–4 Lennard-Jones Potential

Metal−organic frameworks (MOFs) that contain coordinatively unsaturated open metal sites (OMSs) provide strong host− guest interactions, making them promising sorbents for low-concentration gas adsorption applications such as direct air capture and atmospheric water harvesting. However, accurately modeling host−guest interactions involving OMSs remains challenging for classical force fields (FFs) based on the 12−6 Lennard−Jones (LJ) potential, as the polarization effect of the guest molecule induced by the positively charged OMS is not considered. Here, we introduce an FF based on the 12−6−4 LJ potential, which incorporates charge−induced dipole interactions and is parametrized against a diverse set of host−guest potential energy surfaces (PESs) obtained from density functional theory (DFT). The resulting FF, trained on a generic trimetallic cluster, performs well in both host−guest binding energetics and gas adsorption isotherms across different OMS-containing MOFs, including MOF-74 series and Cu-BTC. These results highlight the excellent transferability of our approach and its potential to enhance the accuracy and robustness of high-throughput MOF discovery workflows, particularly for gas adsorption and separation in large and diverse MOF databases.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Adsorptive denitrogenation of model aviation fuel using mesoporous silica in a packed bed adsorption system

This study aims to understand the effects of system process parameters such as flow rate, adsorbent particle size, and use of recycled adsorbent on denitrogenation performance of a model fuel using mesoporous silica gel. The goal is to reduce the nitrogen content of the model fuel from 1500 parts per million to single-digit ppm to meet ASTM specifications for drop-in fuels. This work was done with the intent of applying adsorptive denitrogenation to sustainable aviation fuel (SAF) product fractions produced via hydrothermal liquefaction (HTL). The adsorption performance of the silica is evaluated via packed column breakthrough data, with data generated from collecting from the column outlet and quantifying nitrogen content via gas chromatography. Select experiments use a significantly larger (2.5x column diameter and length) column to demonstrate linear scalability of the process. Thermogravimetric analysis data is collected to evaluate the effects of thermal calcination as a sorbent regeneration method. Effects of a more complex feed are also investigated using a known reference fuel with additional added nitrogen containing compounds. The results presented in this work successfully demonstrate up to 99.8 % removal of NCCs from a model fuel fraction at an original NCC concentration of approximately 1500 ppm to single-digit parts per million after treatment. We also examine calcination of sorbent materials to remove the adsorbed species to enable sorbent reuse and minimize waste generation and show that the calcined material can be reused up to 5 cycles with reduced adsorption capacity. Overall, this work indicates that adsorptive denitrogenation using silica gel is a viable solution to enable the integration of HTL-derived aviation fuels into existing fuel infrastructure.

Adsorption techniques↗
DOE OSTI2022

Impacts of Forest Fire Ash on Aquatic Mercury Cycling

Mercury (Hg) is a ubiquitous contaminant in the environment and its methylated form, methylmercury (MeHg), poses a worldwide health concern for humans and wildlife, primarily through fish consumption. Global production of forest fire ash, derived from wildfires and prescribed burns, is rapidly increasing due to a warming climate, but their interactions with aqueous and sedimentary Hg are poorly understood. In this study, we compared the differences of wildfire ash with activated carbon and biochar on the sorption of aqueous inorganic Hg and sedimentary Hg methylation. Sorption of aqueous inorganic Hg was greatest for wildfire ash materials (up to 0.21 μg g ₋1 or 2.2 μg g ₋1 C) among all of the solid sorbents evaluated. A similar Hg adsorption mechanism for activated carbon, biochar made of walnut, and wildfire ash was found that involves the formation of complexes between Hg and oxygen-containing functional groups, especially the ₋COO group. Notably, increasing dissolved organic matter from 2.4 to 70 mg C L ₋1 remarkably reduced Hg sorption (up to 40% reduction) and increased the time required to reach Hg–sorbent pseudo-equilibrium. Surprisingly, biochar and wildfire ash, but not activated carbon, stimulated MeHg production during anoxic sediment incubation, possibly due to the release of labile organic matter. Overall, our study indicates that while wildfire ash can sequester aqueous Hg, the leaching of its labile organic matter may promote production of toxic MeHg in anoxic sediments, which has an important implication for potential MeHg contamination in downstream aquatic ecosystems after wildfires.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Design and characterization of hierarchical aluminosilicate composite materials for Cs entrapment: Adsorption efficiency tied to microstructure

The growing quantity of nuclear waste and the serious threats to the environment challenge researchers to innovate and target new waste form technologies. In the past decades, considerable efforts have been devoted to developing highly selective sorbents followed by safe disposal with the assurance of chemical stability and robust retention performance. Zeolite-containing geopolymers are regarded as a possible 2-in-1 material able to both capture and sequester elements such as Cs in bed fixed column application perspective. Here, these composites show promise for combining extraction properties of zeolite powder due to its crystalline structure (high capacity and selective adsorption), with the tunable microstructure and the shaping feasibility of the geopolymer binder. For the development of materials devoted to Cs immobilization, porous zeolite/geopolymer composites were prepared by dispersing NaY zeolite particles in a geopolymer binder. The influence of the structural properties of such composites on their ability to entrap a large amount of Cs by an ionic exchange process was notably studied. Composites' compositions, porosities, morphologies and crystallinity were analyzed by scanning electron microscopy coupled with energy dispersive x-ray spectroscopy (SEM-EDX), x-ray diffraction analysis (XRD) and nitrogen adsorption/desorption studies. Experimental Cs sorption in batch mode was used to follow the ionic exchange phenomenon in these materials. Along with 5 wt% amount of zeolite in geopolymer improves the Cs adsorption performance offering multiple new adsorption sites. Additionally, the geopolymer mesopores are beneficial facilitating the access of Cs and its role as a binder is advantageous to tailor granular hierarchical structure for safer industrial application.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Interactions of Polar and Nonpolar Groups of Alcohols in Zeolite Pores

Understanding the quantitative interactions among zeolite pore walls, Bro̷nsted acid sites, and molecules with both polar and nonpolar regions is essential for scoping out the potential of zeolites as sorbents and catalysts. Purely siliceous zeolites (MFI and Beta in the present study) are hydrophobic, whereas those containing aluminum are considered hydrophilic, preferentially adsorbing organic molecules even in aqueous environments. To characterize these interactions, we use primary alcohols of increasing molecular weight, quantifying their specific interactions in the confined pore space of the alkyl (CH x ) and OH groups. Three types of interactions were identified: (i) alkyl CH x groups interacting with the zeolite pore walls (approximately 10 kJ mol −1 per carbon), (ii) alcohol OH groups interacting with the pore walls (30−35 kJ mol −1 ), and (iii) alcohol OH groups interacting with Bro̷nsted acid sites (37 kJ mol −1 ). All three interactions were well mirrored by computational simulations. The contribution of the alkyl CH x groups was inferred from the incremental increase in sorption enthalpy with increasing molecular weight; the interaction strength of the OH groups was determined by extrapolating the global adsorption enthalpy of the alcohols to a hypothetical OH group without an alkyl group. This value was identical to the adsorption enthalpy of water. The experiments demonstrated that only water has an adsorption enthalpy on zeolite pore walls lower than its condensation enthalpy (30−35 kJ mol −1 vs 45 kJ mol −1 ), limiting the concentration of water that can be adsorbed.

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

The Effects of Iron and Manganese Doping on the Carbonation of Brucite [Mg(OH) 2 ]

Brucite [Mg(OH) 2 ] is a promising sorbent for carbon dioxide removal (CDR) due to its availability and low calcination temperatures. However, natural and synthetic brucites tend to contain metal impurities, such as iron or manganese, and how these impurities affect the interfacial chemical reactivity is uncertain. Here, in this study, the impact of low concentrations of iron and manganese impurities on the carbonation efficiency of Mg(OH) 2 was examined. Mg(OH) 2 with small amounts (1–5 mol %) of Fe and Mn was synthesized. The increasing substitution of Fe into Mg(OH) 2 was accompanied by the oxidation of Fe. The phase transformation sequence during the carbonation was found to be brucite [Mg(OH) 2 ] → amorphous magnesium carbonate (MgCO 3 ·nH 2 O) → nesquehonite (MgCO 3 ·3H 2 O), regardless of impurity concentration. Both the Fe- and Mn-doped Mg(OH) 2 samples were more reactive than endmember Mg(OH) 2 , possibly due to their higher surface areas and lower stabilities. During carbonation, 3 mol % Fe- and Mn-doped Mg(OH) 2 showed the highest reactivity. The variance in reactivity for Mn-doped Mg(OH) 2 was less than that of Fe-doped Mg(OH) 2 . These results suggest that natural or industrial waste Mg(OH) 2 with less than 5 mol % Fe and Mn impurities may be targeted as more effective CDR sorbents than endmember Mg(OH) 2 .

Carbon dioxide removal↗
DOE OSTI2026

Aqueous Carbon Capture Using Guanidinium-Functionalized Hollow Fiber Sorbent Contactors

As part of the growing suite of technologies aimed at combatting rising temperatures, negative emissions technologies have become a powerful tool in the global effort to minimize the consequences of human-induced climate change. Among these, carbon removal from aqueous sources, which contain much higher carbon concentrations than the atmosphere, remains largely unexplored. Indeed, developing robust and efficient carbon capture materials for usage in complex aqueous environments remains a significant challenge. Here, we explore the potential of functionalizing polyvinylidene fluoride (PVDF) hollow fiber contactors grafted with a guanidinium-derived polymer sorbent for carbon removal from aqueous sources, including saline waters. Computational screening against amine-based analogs is utilized to identify guanidinium as a promising motif for bicarbonate (HCO 3 – ) ions binding. To leverage this finding, synthesis of a guanidinium polymer and subsequent covalent grafting onto PVDF hollow fibers is employed to structured polymer–sorbent–grafted hollow fiber contactors. Our prototype achieves an initial HCO 3 – removal of 34% with an increase to 98% after four cycles. The functionalized fibers demonstrate aqueous stability over 13 adsorption/desorption cycles in model NaHCO 3 solutions where regeneration is facilitated by a mild pH swing. Importantly, the system maintains selective performance in the presence of competitive chloride ions over multiple cycles; carbon removal remained above 10% even at high (10:1) NaCl/NaHCO 3 ratios. These findings demonstrate the feasibility of sorbent-based aqueous carbon removal and highlight its potential as a promising approach for negative emissions.

carbon capture↗
DOE OSTI2024

Effective direct steam regeneration of bis-iminoguanidine solid sorbent used for carbon dioxide capture

A cost-effective, energy-efficient sorbent regeneration process for phase-changing guanidines used for CO 2 capture was developed based on direct-steam stripping. This approach enhances the regeneration rate, simplifies the overall CO 2 capture process, and reduces the energy cost compared to conventional conductive thermal regeneration. A direct-steam sorbent regeneration reactor was developed, demonstrating that aqueous bis(iminoguanidines) (BIG) sorbents, e.g., methylglyoxal-bis(iminoguanidine) (MGBIG) and glyoxal-bis(iminoguanidine) (GBIG), could be efficiently regenerated with up to ~ 99 % CO 2 recovery through direct-steam stripping. Using low-temperature steam at 100 °C, a 4.5 times faster regeneration rate for GBIG carbonate sorbent (e.g., 30 min for 10 g) was demonstrated compared to conductive-heating (e.g., 135 min for 10 g) at 130 °C. Additionally, fully regenerated MGBIG converts into an aqueous MGBIG solution when the steam condenses onto the sorbent surface. Condensed steam with the guanidine can be easily recycled as an aqueous solution into the gas–liquid contactor to achieve a continuous-flow CO 2 -capture process. Molecular dynamics simulation was employed to provide a better understanding of the process. Higher heat transfer rates from steam to guanidine carbonate, compared to air heating, were attributed to the vibration resonance of water molecules within MGBIG with that of vapor molecules and the effective transfer of kinetic energy from vapor to solid. Technoeconomic analysis demonstrated that direct-steam stripping significantly decreases the CO 2 capture cost by 50 % compared to traditional conductive heating methods. Further, enhanced mass transfer facilitated by low-temperature steam and subsequent condensation effectively heats up the H 2 O-containing BIG-carbonate crystals, facilitating the desorption of CO 2 from the solid crystals, thereby leading to fast, effective, and energy-efficient sorbent regeneration.

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

Tailoring Chemical Absorption-Precipitation to Lower the Regeneration Energy of a CO 2 Capture Solvent

Solvent-based CO 2 capture consumes significant amounts of energy for solvent regeneration. To improve energy efficiency, this study investigates CO 2 fixation in a solid form through solvation, followed by ionic self-assembly-aided precipitation. Based on the hypothesis that CO 3 2- ions may bind with monovalent metal ions, we introduced Na + into an aqueous hexane-1,6-diamine solution where CO 2 forms carbamate and bicarbonate. Then, Na + ions in the solvent act as a seed for ionic self-assembly with diamine carbamate to form an intermediate ionic complex. The recurring chemical reactions lead to the formation of an ionic solid from a mixture of organic carbamate/carbonate and inorganic sodium bicarbonate (NaHCO 3 ), which can be easily removed from the aqueous solvent through sedimentation or centrifugation and heated to release the captured CO 2 . Mild-temperature heating of the solids at 80–150 °C causes decomposition of the solid CO 2 -diamine-Na molecular aggregates and discharge of CO 2 . This sorbent regeneration process requires 6.5–8.6 GJ/t CO 2 . It was also found that the organic carbamate/carbonate solid, without NaHCO 3 , contains a significant amount of CO 2 , up to 6.2 mmol CO 2 /g-sorbent, requiring as low as 2.9–5.8 GJ/t CO 2 . In conclusion, molecular dynamic simulations support the hypothesis of using Na + to form relatively less stable, yet sufficiently solid, complexes for the least energy-intensive recovery of diamine solvents compared to bivalent carbonate–forming ions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Process of producing ethylene

A process of producing ethylene involving steam cracking ethane to produce a steam cracker product stream containing ethylene; cooling and drying the steam cracker product stream; contacting the cooled and dried steam cracker product stream with a MOF sorbent capable of adsorbing ethylene from the product stream, and desorbing the ethylene from the MOF sorbent using an ethylene sweep gas. The process replaces complex and energy intensive fractionation steps of the prior art with a selective adsorption step for separating ethylene from the steam cracker product stream. An energy efficient ethylene sorbent regeneration method and related apparatus systems are also disclosed.

Weissman, Jeffrey G.↗
DOE OSTI2023

Densification and Immobilization of AgI-Containing Iodine Waste Forms Using Spark Plasma Sintering

Here in this study, porous Ag-xerogel (Ag-Xero), Ag-faujasite (Ag-FAU) zeolite, and Ag-mordenite (Ag-MOR) zeolite sorbents were loaded with iodine gas [I 2 (g)] under saturated conditions at 150 °C for 24 h, followed by densification and consolidation into monolithic waste forms using spark plasma sintering (SPS). For Ag-Xero materials, SPS pellets were made with as-loaded samples, while others were made with preheated (PH; 500 °C for 2 h) samples to help with densification. SPS processing was conducted at 50 MPa under different temperatures (T = 200–800 °C) for different times (t = 0.5–30 min), where eleven AgI-Xero samples, five AgI-FAU, and two AgI-MOR separate samples were produced. The primary goal was to look for the optimum processing parameters for each material to yield pellets with high iodine retentions, high densities, and low porosities while preventing AgI decomposition. The Ag-Xero showed the highest iodine loadings (qe = 470 mg g –1 ) compared to Ag-FAU (qe = 368 mg g –1 ) and Ag-MOR (qe = 108 mg g –1 ). Measured iodine concentrations were the highest in AgI-Xero pellets without PH, followed by AgI-Xero with PH, AgI-FAU, and then AgI-MOR. Silver utilization (I/Ag on a mol % basis) values were in the order of AgI-MOR ≈ AgI-Xero (no PH) > AgI-Xero (PH) > AgI-FAU. Chemical durabilities of SPS-densified AgI-Xero (PH) pellets were very favorable, with lower releases than SPS pellets made from AgI-Xero samples without PH. These results show promise for iodine waste form production.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗