Molten Salt Processes

After a study of the three alternatives we concluded that pyroredox offered the most promise for anode residue recovery. Pyroredox is a molten-salt process in which plutonium metal is oxidized chemically into the salt phase and then reduced chemically into the metal phase. Most of the impurities are not oxidized and remain in the metal residue. Thus, for a Pu-Ga anode residual, the reactions would be ... 

Conventional thermal treatment methods, such as rotary kiln, rotary hearth furnace, or fluidized-bed furnace, are used for waste pyrolysis. Molten salt process may also be used for waste pyrolysis. 

Dunbobbin, B. R. and W. R. Brown. 1987. Air separation by a high temperature molten salt process. Gas separation and purification 1 23-29. 

The advantage of electro over thermal incineration is that no noxious materials are added to the environment. It seems likely that rubbish disposal in general will become electrochemical. Low-temperature (-250 °C) molten salt processes may be necessary for tougher cases (Lin, 1997). Low current density Cl2 evolution may be introduced as a biocide when necessary, particularly in treatment of aqueous electrolytic sewage involving urine (Kaba, 1990 Tennakoon, 1993). 

Mishra, B., D.L. Olson and P.D. Ferro, 1994, Application of ceramic membranes in molten salt processing of radioactive wastes, in Proc. 123rd Ann. Meeting of Minerals, Metals, and Mater. Soc., San Francisco, USA, p. 233. 

An example of the gasification of biomass by partial oxidation in which air is supplied without zone separation in the gasifier is the molten salt process (Yosim and Barclay, 1976). In this process, shredded biomass and air are... 

Figure 1. Molten salt process for fuel production from wastes...

Molten salt processes, as the name implies, use a molten medium of an inorganic salt to generate the heat to decompose the coal into products. 

Molten salt processes for refining metals as diverse as lead, beryllium, magnesium, molybdenum and uranium have been described but are probably never used commercially. 

Ping GZ, Du GD, Yanna N, Hassan MF, Liu HK. Ultra-fine porous Sn02 nanopowder prepared via a molten salt process a highly efficient anode material for hthium-ion batteries. J Mater Chem 2009 19 3253-7. 

The tabular ST particles were synthesized by a two-step molten salt process using KCl as a flux. The ST platelets served as templates. Figure 4.59 shows by XRD the random and textured PMN-32.5PT (3 wt% excess PbO, 3 vol% ST) ceramics sintered at 1150 °C for 10 h. The two major peaks in the templated PMN-32.5PT ceramic were (100) and (200), which indicates the high degree of texmring. In the textured XRD, a reflection of the (100) remained, indicating that the texturing did not entirely reach completion. The piezoelectric behavior of the ST and BT6 (i.e.. 

Once the principles of operating in a molten salt environment have been grasped, suitable extrapolations or interpolations of materials requirements and cell and equipment designs can be made between different systems. In bringing a molten salt process into commercial operation, unique materials problems requiring special solutions often limit its progress, but practically never prevent it. Thus, if a desired result may not be achieved for theoretical reasons in any alternative electrolyte, because of electrochemical instability, for example, then initial development costs and difficulties become inconsequential. Such has been the case with thermal batteries, " sodium-sulfur batteries, molten fluoride nuclear reactors, and molten carbonate fuel... 

All processing methods however require far more development before commercial operations. While molten salt processes may be far simpler than solid fuel processes, they still represent a large capital and regulatory burden. As an example, the 1970s 1000 MWe MSBR design called for processing the entire fuel salt every 10 days, which would equate to 5600 tonnes processed per annum. 

TfflS SECTION INCLUDES TESTS for determining the materials of construction requirements for equipment used for manufacturing chemicals. This includes both bulk chemicals, which are typically manufactured in dedicated equipment in large quantities, and specialty chemicals, which are most often made in smaller quantities and often in equipment used for more than one process. Tests for both organic and inorganic chemicals eure included. Because some tests require the presence of an electrolyte, they are not suitable for many pure organic processes. Equipment intended for use in the pharmaceutical, petrochemical, or high-temperature gas phase or molten salt processes have special requirements that are not included in this section. 

Worldwide, the electrolytic production of aluminum is the second largest consumer of electrical energy for electrochemical processes. It is a molten salt process at high temperature ( 1250K). Consumable anodes are used and the overall reaction is ... 

Organic Electrolytes. One of the major drawbacks of any molten salt process for electrodeposition is the energy needed to maintain the system in its molten state. The energy that is added either by external heaters or by Joule heating must add to the cost of the final product. 

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