A5072395832- Radioactive element chemistry and processing
- Radioactive contamination and transfer
- Chemical Synthesis and Characterization
- Geochemistry and Elemental Analysis
- Environmental Toxicology and Ecotoxicology
- Water Quality and Pollution Assessment
- Mercury impact and mitigation studies
- Radioactivity and Radon Measurements
- Marine and fisheries research
- Isotope Analysis in Ecology
- Geology and Paleoclimatology Research
- Analytical chemistry methods development
- Electrochemical Analysis and Applications
- Extraction and Separation Processes
- Advanced Data Processing Techniques
- Archaeology and ancient environmental studies
- Per- and polyfluoroalkyl substances research
- Scientific Research and Discoveries
- Smart Materials for Construction
- Non-Destructive Testing Techniques
- Toxic Organic Pollutants Impact
- Water Treatment and Disinfection
- Material Properties and Applications
- Environmental Chemistry and Analysis
- Urban Stormwater Management Solutions
Pacific Northwest National Laboratory
2015-2022
Battelle
2020
The Pacific Northwest National Laboratory (PNNL) is evaluating the performance of adsorption materials to extract uranium from natural seawater. Testing consists measurements and other elements seawater as a function time using flow-through columns recirculating flume determine adsorbent capacity kinetics. amidoxime-based polymer AF1, produced by Oak Ridge (ORNL), had 56-day 3.9 ± 0.2 g U/kg material, saturation 5.4 half-saturation 23 2 days. ORNL AF1 has very high affinity for uranium,...
The Marine Science Laboratory at the Pacific Northwest National evaluated impact of biofouling on performance or uranium adsorbents. A surface-modified polyethylene adsorbent fiber provided by Oak Ridge Laboratory, AF adsorbent, was tested in either presence absence light to simulate deployment shallow deep marine environments. Samples were exposed seawater as loose fibers packed with glass beads columns and >10-cm-long braids placed a flume that continuous flow representative natural ocean...
High-surface-area amidoxime and carboxylic acid grafted polymer adsorbents developed at Oak Ridge National Laboratory were tested for sequestering uranium in a flowing seawater flume system the PNNL-Marine Sciences Laboratory. FTIR spectra indicate that KOH conditioning process is necessary to remove proton from make sorbent effective seawater. The alkaline also converts groups carboxylate adsorbent. Both Na2CO3–H2O2 hydrochloric elution methods can ∼95% of sequestered by adsorbent after 42...
Extraction of uranium (U) from seawater for use as a nuclear fuel is significant challenge due to the low concentration U in (∼3.3 ppb) and difficulties selectively extract background major trace elements seawater. The Pacific Northwest National Laboratory (PNNL)'s Marine Sciences (MSL) has been serving marine test site determining performance characteristics (adsorption capacity, adsorption kinetics, selectivity) novel amidoxime-based polymeric adsorbents developed at Oak Ridge (ORNL) under...
The ability to reuse amidoxime-based polymeric adsorbents is a critical component in reducing the overall cost of technology extract uranium from seawater. This report describes an evaluation adsorbent reusability multiple (adsorption/stripping) cycles real seawater exposures with potassium bicarbonate (KHCO3) elution using several adsorbents. KHCO3 technique achieved ∼100% recovery adsorption capacity first reuse. Subsequent reuses showed significant drops capacity. After fourth ORNL AI8...
Abstract Recent advances in the development of amidoxime‐based adsorbents have made it highly promising for seawater uranium extraction. However, there is a great need to understand influence temperature on sequestration performance natural seawater. Here apparent enthalpy and entropy sorption (VI) vanadium (V) with were determined tests at 8, 20, 31 °C that cover broad range ambient temperature. The U was endothermic, producing enthalpies 57 ± 6.0 59 11 kJ mol −1 entropies 314 21 320 36 J K...
Utilizing spectroscopic and microscopic techniques to understand the KOH conditioning process required for preparing high-surface-area amidoxime-based polymer fiber adsorbents sequestering uranium from real seawater.
Passive adsorption using amidoxime-based polymeric adsorbents is being developed for uranium recovery from seawater. The local oceanic current velocity where the adsorbent deployed a key variable in determining locations that will maximize rates. Two independent experimental approaches flow-through columns and recirculating flumes were used to assess influence of linear on uptake kinetics by adsorbent. Little no difference was observed rate vs seawater exposure columns. In contrast, results...
Trace element determinations in seawater by inductively coupled plasma mass spectrometry are analytically challenging due to the typically very low concentrations of trace elements and potential interference salt matrix. In this study, we did a comparison for uranium analysis using (ICP-MS) Sequim Bay samples three certified reference materials (SLEW-3, CASS-5, NASS-6) eight different analytical approaches. The methods evaluated include following: direct analysis, Fe/Pd reductive...
A variety of adsorbent materials have been developed to extract uranium from seawater as an alternative traditional terrestrial mining. large-scale deployment these adsorbents would be necessary recover useful quantities uranium, and this raises a number concerns regarding potential impacts on the surrounding marine environment. Two are whether or not toxic any potentially harmful effects that may result depleting vanadium (also highly concentrated by adsorbents) local To test toxicity with...
Declining primary production has been proposed as an explanation for the declines in coho (Oncorhynchus kisutch) and Chinook tshawytscha) salmon Salish Sea since 1970s. Marine sediments maintain a continuous record of conditions overlying water. We used stable isotopes organic carbon nitrogen measured 21 sediment cores to determine contributions fluxes marine-derived terrigenous matter over time. The flux shows no trend at least last 100 years. An apparent increase marine recent years is due...
Global demand for nuclear energy is expected to rise in the coming decades. To meet these growing needs, new uranium resources must be explored. One of potential alternatives traditional mining oceanic uranium. The capture and recovery from ocean have been under investigation some time, with many recent studies focused on amidoxime-based adsorbents. These adsorbents, while able achieve high capacities, are, nevertheless, expensive produce adsorb a significant amount hard-to-remove vanadium....
Abstract Diffusive gradient in thin films (DGT) potentially better quantifies bioavailable copper (Cu) seawater. Laboratory exposure of DGTs and Mytilus galloprovincialis embryos at varying concentrations dissolved organic carbon Cu were performed to resolve the degree which mimicry toxicity buffering occurs passive sampler quantification. The results provide preliminary median effect (EC50s) ranging from 4.8 11.5 µg/L as C DGT over span 0.896 8.36 mg/L DOC. Environ Toxicol Chem 2019;00:1‐6....
One critical challenge of the development seawater uranium extraction is to make adsorbents perform well in complex real matrix, which comprised many competing ions and natural organic substances. Here, we conducted a systematic study using continuous-flow flume system assess potential impacts dissolved matter (DOM) iron on uptake performance, including adsorbent reusability, amidoxime-based adsorbents. In 28-day exposure, exposed Fe-spiked (low DOM/high Fe) humic acid-spiked (high showed...
Determination of the median effective concentration (EC50) Cu on Mytilus galloprovincialis larvae by diffusive gradient in thin films (DGT) has been shown to effectively reduce need consider dissolved organic carbon (DOC) and quality. A standard toxicity test protocol was used validate previously modeled protective effects, afforded highly sensitive marine ligand competition, 5 diverse site waters. The results demonstrate significant narrowing M. toxicological endpoints, where EC50s ranged...
Abstract This research compares performance, reproducibility, and detection limits of ambient seawater analysis for trace metals using both borohydride reductive coprecipitation an automated chelation column (seaFAST™ 2) preconcentration matrix interferent elimination on total dissolved grab samples in nearshore to marine waters, over a broad concentration range, prior inductively coupled plasma mass spectrometry (ICP‐MS) injection. A move online method minimizes sample preparation,...