The Experts below are selected from a list of 23787 Experts worldwide ranked by ideXlab platform

Karim Adil - One of the best experts on this subject based on the ideXlab platform.

Glatz Jean-paul - One of the best experts on this subject based on the ideXlab platform.

  • Spent Fuel Dissolution and Reprocessing Processes
    Elsevier Ltd., 2012
    Co-Authors: Glatz Jean-paul
    Abstract:

    The initial motivation for the development of reprocessing technologies was to obtain pure fissile material for nuclear weapon production. Most prominent is the PUREX (Plutonium and Uranium Extraction) process, still used today world-wide to reprocess commercial LWR (Light Water Reactor) fuels at a few thousand tons per year scale. The fuels dissolved in nitric acid are contacted with a TBP (Tributyl Phosphate) based solvent, the extracted uranium and plutonium are further purified and the raffinate vitrified for a safe final disposal. Plutonium is partly recycled as MOX fuel. Since the beginning of this century a new generation of nuclear reactors is being developed in the frame of the so-called generation IV initiative. To comply with the sustainability goals defined for the innovative reactor systems mainly the waste minimization through recycling of all actinides, the corresponding fuel cycles will play a central role in trying to achieve these goals. The new concept of a grouped actinide Separation can be derived from aqueous or pyro-chemical partitioning processes. For the aqueous schemes a direct link to PUREX is obvious, namely with co-extraction of Np. The extraction of the remaining actinides can be achieved by using specially designed solvents based on phosphine oxide or diamide molecules. A major focus is on the very Challenging Separation of lanthanides from the trivalent actinides. The process implementation, especially for the less pyro-metallurgy, require a good basic understanding on the extraction mechanisms. Pyro-reprocessing where all actinides are recycled is based on metallic fuels, those are dissolved in molten salts at around 500-900°C and actinides are selectively recovered, either by electrorefining or extraction into a liquid metal phase. The fuels of new generation reactors will, at least in the beginning, most likely be oxides. Thus, for pyro-processes a head-end reduction step for oxide- into metals fuels is needed. A very specific reprocessing technology, the so-called DUPIC (Direct Use of Pressurized Water Reactor Spent Fuel in CANDU) process, is being developed in Korea. Here used PWR (Pressurized Water Reactor) fuel is recycled to CANDU (CANada Deuterium Uranium) reactors after a dry treatment where volatile fission products are being removed.JRC.E.5-Nuclear chemistr

  • Spent fuel dissolution and reprocessing processes
    Elsevier Ltd, 2011
    Co-Authors: Glatz Jean-paul
    Abstract:

    The initial motivation for the development of reprocessing technologies was to obtain pure fissile material for nuclear weapon production. Most prominent is the PUREX (Plutonium and Uranium Extraction) process, still used today world-wide to reprocess commercial LWR (Light Water Reactor) fuels at a few thousand tons per year scale. The fuels dissolved in nitric acid are contacted with a TBP (Tributyl Phosphate) based solvent, the extracted uranium and plutonium are further purified and the raffinate vitrified for a safe final disposal. Plutonium is partly recycled as MOX fuel. Since the beginning of this century a new generation of nuclear reactors is being developed in the frame of the so-called generation IV initiative. To comply with the sustainability goals defined for the innovative reactor systems mainly the waste minimization through recycling of all actinides, the corresponding fuel cycles will play a central role in trying to achieve these goals. The new concept of a grouped actinide Separation can be derived from aqueous or pyro-chemical partitioning processes. For the aqueous schemes a direct link to PUREX is obvious, namely with co-extraction of Np. The extraction of the remaining actinides can be achieved by using specially designed solvents based on phosphine oxide or diamide molecules. A major focus is on the very Challenging Separation of lanthanides from the trivalent actinides. The process implementation, especially for the less pyro-metallurgy, require a good basic understanding on the extraction mechanisms. Pyro-reprocessing where all actinides are recycled is based on metallic fuels, those are dissolved in molten salts at around 500-900°C and actinides are selectively recovered, either by electrorefining or extraction into a liquid metal phase. The fuels of new generation reactors will, at least in the beginning, most likely be oxides. Thus, for pyro-processes a head-end reduction step for oxide- into metals fuels is needed. A very specific reprocessing technology, the so-called DUPIC (Direct Use of Pressurized Water Reactor Spent Fuel in CANDU) process, is being developed in Korea. Here used PWR (Pressurized Water Reactor) fuel is recycled to CANDU (CANada Deuterium Uranium) reactors after a dry treatment where volatile fission products are being removed.JRC.E-Institute for Transuranium Elements (Karlsruhe

Pfennig Andreas - One of the best experts on this subject based on the ideXlab platform.

  • Aerated extraction columns for in situ Separation of bio-based diamines from cell suspensions
    'Wiley', 2019
    Co-Authors: Bednarz Andreas, Jupke Andreas, Spieß, Antje C., Pfennig Andreas
    Abstract:

    BACKGROUND: Extraction is the method of choice for separating sensitive products. For example, it has been applied in aromatics and rare-earth metal Separation. Recently, biotechnological processes entered the field of bulk chemicals andmight benefit fromprocess intensification by in situ extraction of inhibiting products, however in the presence of cells and/or aeration. This study applies reactive extraction of the polyamide monomer hexane-1,6-diamine fromcell-containingmedium. RESULTS: To prove technical feasibility of this reactive extraction, simulation of the extraction column based on single-drop measurements was validated at pilot-scale. Simulated results show good accordance with experimental data with an error below 20%. The extraction column was subsequently used as a bioreactor with integrated aeration and product extraction applying a four-phase system investigating the effect on drop distributions and holdup of the dispersed phases. Interestingly, aeration increased the holdup up to five-fold and decreased themean drop size of the organic extractive phase by 30%, thereby potentially improving extraction efficiency. CONCLUSION: The ReDrop simulation tool is capable of predicting Challenging Separation processes like the reactive extraction of hexane-1,6-diamine with D2EHPA diluted in oleyl alcohol from a biotransformation medium. The process design enabled four-phase operation of the column with aeration, extractive organic phase and cell-containing continuous aqueous phase.Peer reviewe

  • Aerated extraction columns for in situ Separation of bio-based diamines from cell suspensions
    'Wiley', 2019
    Co-Authors: Bednarz Andreas, Jupke Andreas, Spieß, Antje C., Pfennig Andreas
    Abstract:

    peer reviewedaudience: researcher, professionalBACKGROUND: Extraction is the method of choice for separating sensitive products. For example, it has been applied in aromatics and rare-earth metal Separation. Recently, biotechnological processes entered the field of bulk chemicals andmight benefit fromprocess intensification by in situ extraction of inhibiting products, however in the presence of cells and/or aeration. This study applies reactive extraction of the polyamide monomer hexane-1,6-diamine fromcell-containingmedium. RESULTS: To prove technical feasibility of this reactive extraction, simulation of the extraction column based on single-drop measurements was validated at pilot-scale. Simulated results show good accordance with experimental data with an error below 20%. The extraction column was subsequently used as a bioreactor with integrated aeration and product extraction applying a four-phase system investigating the effect on drop distributions and holdup of the dispersed phases. Interestingly, aeration increased the holdup up to five-fold and decreased themean drop size of the organic extractive phase by 30%, thereby potentially improving extraction efficiency. CONCLUSION: The ReDrop simulation tool is capable of predicting Challenging Separation processes like the reactive extraction of hexane-1,6-diamine with D2EHPA diluted in oleyl alcohol from a biotransformation medium. The process design enabled four-phase operation of the column with aeration, extractive organic phase and cell-containing continuous aqueous phase

Abdul Manan Zainuddin - One of the best experts on this subject based on the ideXlab platform.

  • Effects of ultrasonic waves on vapor-liquid equilibrium of an azeotropic mixture
    'Informa UK Limited', 2009
    Co-Authors: Ripin Adnan, Abdul Mudalip, Siti Kholijah, Sukaimi Zairina, Mohd. Yunus Rosli, Abdul Manan Zainuddin
    Abstract:

    Azeotropic and extractive distillation techniques used to separate azeotropic mixtures are among the most Challenging Separation processes in the chemical industry. In this work, an innovative distillation technique which employed ultrasonic waves was proposed to intensify the conventional multi-column azeotropic distillation method into a single-column alternative. The effects of ultrasonic intensity on the vapor-liquid equilibrium (VLE) of methyl-terf-butyl-ether (MTBE)-methanol was investigated at 50, 100, 200, and 250 W/A. cm2 and at a fixed frequency of 40 kHz. Studies were also done to examine the effects of ultrasonic frequency on the VLE data at 25 and 68 kHz frequencies. It was found that ultrasonic waves at 50 W/A.cm2 intensity and 25 kHz frequency gave the highest relative volatility (a) at 2.654 and completely eliminated the MTBE-methanol azeotrope, thereby allowing highly pure MTBE to be recovered in just a single distillation column. The results revealed that ultrasonic waves had the potential to favorably manipulate a, and hence, the VLE of an azeotropic mixture

Dongxu Xue - One of the best experts on this subject based on the ideXlab platform.