A5010895520- Radioactive element chemistry and processing
- Chemical Synthesis and Characterization
- Radioactive contamination and transfer
- Nuclear and radioactivity studies
- Photopolymerization techniques and applications
- Fiber-reinforced polymer composites
- Advanced Chemical Physics Studies
- Biodiesel Production and Applications
- Superconducting Materials and Applications
- Epoxy Resin Curing Processes
- Silicone and Siloxane Chemistry
- Thermochemical Biomass Conversion Processes
- Extraction and Separation Processes
- Atomic and Molecular Physics
- Recycling and Waste Management Techniques
- Laser-Matter Interactions and Applications
- Thermography and Photoacoustic Techniques
- Metallurgy and Material Science
- Mass Spectrometry Techniques and Applications
- Additive Manufacturing and 3D Printing Technologies
- HVDC Systems and Fault Protection
- Engineering Applied Research
- Geochemistry and Elemental Analysis
- biodegradable polymer synthesis and properties
- Nuclear Materials and Properties
Oak Ridge National Laboratory
2015-2024
Embry–Riddle Aeronautical University
2024
Goethe University Frankfurt
2016-2022
Government of the United States of America
2021
Oak Ridge Associated Universities
2014-2020
Vaughn College of Aeronautics and Technology
2018
National Transportation Research Center
2018
Greenfield Community College
2017
Nexans (Germany)
2012
Office of Scientific and Technical Information
2012
Uranium recovery from seawater has been investigated for several decades the purpose of securing nuclear fuel energy production. In this study, field column experiments have performed at Marine Sciences Laboratory Pacific Northwest National (PNNL) using a laboratory-proven, amidoxime-based polymeric adsorbent developed Oak Ridge (ORNL). The was packed either in in-line filters or flow-through columns. maximum amount uranium uptake 3.3 mg U/g after 8 weeks contact between and seawater. This...
A new family of high-surface-area polyethylene fiber adsorbents named the AF series was recently developed at Oak Ridge National Laboratory (ORNL). The were synthesized by radiation-induced graft polymerization acrylonitrile and itaconic acid (at different monomer/comonomer mol ratios) onto high surface area fibers. degree grafting (%DOG) found to be 154–354%. grafted nitrile groups converted amidoxime treating with hydroxylamine. amidoximated then conditioned 0.44 M KOH 80 °C followed...
Fiber adsorbents synthesized<italic>via</italic>ATRP.
A new series of adsorbents (AI10 through AI17) were successfully developed at ORNL by radiation induced graft polymerization (RIGP) acrylonitrile (AN) and vinylphosphonic acid (VPA) (at different mole to ratios) onto high surface area polyethylene fiber, with degrees grafting (DOG) varying from 110 300%. The grafted nitrile groups converted amidoxime reaction 5 wt % hydroxylamine 80 °C for 72 h. amidoximated then conditioned 0.44 M KOH followed screening prescreening brine spiked 8 ppm...
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...
The ocean contains uranium with an approximate concentration of 3.34 ppb, which can serve as incredible supply source to sustain nuclear energy in the United States. Unfortunately, technology currently available recover from seawater is not efficient enough and mining on land still more economical. We have developed polymer-based adsorbents high adsorption capacities by grafting amidoxime onto high-surface-area polyethylene (PE) fibers. Various process conditions been screened, combination...
Uranium adsorbed on amidoxime-based polyethylene fiber in simulated seawater can be quantitatively eluted at room temperature using 1 M Na2CO3 containing 0.1 H2O2. This efficient elution process is probably due to the formation of an extremely stable uranyl-peroxo-carbonato complex carbonate solution. After washing with water, sorbent reused minimal loss uranium loading capacity. Possible existence this uranyl species ocean water also discussed.
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...
A laboratory study of uranium uptake from seawater has been conducted using batch and flow-through recycling experiments. Uranium adsorption seawater, amidoxime-based polymeric adsorbents, described by transport kinetic models under the assumption transport-limited or reaction-limited process for Mathematical based on liquid film mass transfer, diffusion, reaction kinetics have evaluated in terms Sherwood number Thiele modulus to provide insight into limiting mechanism. The value suggests...
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...
A high-surface-area polyethylene-fiber adsorbent (AF160-2) has been developed at the Oak Ridge National Laboratory by radiation-induced graft polymerization of acrylonitrile and itaconic acid. The grafted nitriles were converted to amidoxime groups treating with hydroxylamine. amidoximated adsorbents then conditioned potassium hydroxide (KOH) varying different reaction parameters such as KOH concentration (0.2, 0.44, 0.6 M), duration (1, 2, 3 h), temperature (60, 70, 80 °C). Adsorbent...
Alkaline conditioning of the amidoxime based adsorbents is a significant step in preparation adsorbent for uranium uptake from seawater. The effects various alkaline parameters such as type reagent, reaction temperature, and time were investigated with respect to adsorption capacity simulated seawater (spiked 8 ppm uranium) natural (from Sequim Bay, WA). An (AF1) was prepared at Oak Ridge National Laboratory by radiation-induced graft polymerization (RIGP) acrylonitrile itaconic acid onto...
Resistive superconducting fault current limiters (rSFCL) are reliably reacting devices and excellent means to overcome issues of higher short circuit levels resulting from added electricity generation more interconnected networks. Due the strong impedance increase superconductor components initiated by a very low reactance under all operating conditions rSFCL technology is ideal for protection grids. Several systems based on different materials have been designed, built, tested, commissioned...
Seawater contains a large amount of uranium (∼4.5 billion tons) which can serve as nearly limitless supply for an energy source. However, to make the recovery from seawater economically feasible, lower manufacturing and deployment costs are desirable, good solid adsorbents must have high uptake, reusability, selectivity toward uranium. In this study, atom-transfer radical polymerization (ATRP), without high-cost radiation-induced graft polymerization, was used grafting acrylonitrile...
We report on a joint experimental and theoretical study of photoelectron circular dichroism (PECD) in methyloxirane. By detecting O 1s-photoelectrons coincidence with fragment ions, we deduce the molecule's orientation emission direction laboratory frame. Thereby, retrieve fourfold differential PECD clearly beyond 50%. This strong chiral asymmetry is reproduced by ab initio electronic structure calculations. Providing such pronounced contrast makes fixed-in-space molecules an even more...
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...
Brush-on-brush structures are proposed as one method to overcome support effects in grafted polymers. Utilizing glycidyl methacrylate (GMA) on polyethylene (PE) fibers using radiation-induced graft polymerization (RIGP) provides a hydrophilic surface the hydrophobic PE. When integrated with atom transfer radical (ATRP), grafting of acrylonitrile (AN) and hydroxyethyl acrylate (HEA) can be controlled manipulated more easily than RIGP. Poly(acrylonitrile)-co-poly(hydroxyethyl acrylate) chains...
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...
Chirality is omnipresent in living nature. On the single molecule level, response of a chiral species to probe depends on their respective handedness. A prominent example difference interaction with left or right circularly polarized light. In present study, we show by Coulomb explosion imaging that light can also induce fragmentation planar and thus achiral molecule. The observed enantiomer strongly orientation respect propagation direction helicity ionizing This finding might trigger new...
An amidoxime and carboxylate containing chelating adsorbent derived from acrylic fiber shows a fast adsorption rate high uranium low vanadium capacities in real seawater tests.