Eutectic salts

An important iadustrial use of NaH involves its in situ formation ia molten NaOH or ia fused eutectic salt baths. At concentrations of 1—2% NaH, these compositions are powerful reducing systems for metal salts and oxides (5). They have been used industrially for descaling metals such as high alloy steels, titanium, zirconium, etc. 

The overall chemical reaction of the chlorinated organics by Li2C03-Na2C03 eutectic salt is given by the following equation. 

The LCM baths use a mixture of nitrate/nitrite eutectic salts. As it contains up to 40% sodium nitrite the salt system is toxic and can cause water pollution, and also cause nitrosation of volatile secondary amines. 

Humidity Equilibration. The clays were humidified at 25°C in desiccators using a series of eutectic salts. Each dessicator was controlled at a different relative humidity using one of the saturated salt solutions listed in Table II. The samples were weighed repeatedly until equilibrium (constant weight) was reached. After the spectra were obtained, the samples were broken into three aliquots, reweighed and dried for -24 hours at 105°C to obtain the dry weights of the clay, from which the water contents were calculated. The water contents, as percent dry weight of the clay, are also shown in Table II. 

Table II. Eutectic Salts and Desiccants Used in Relative...

Representative reactions and products are listed in Table 1. Lithium and Na hydride reductions are performed in ether, although with SiCl eutectic salts can be used. In large-scale syntheses NaH is prepared in situ from reaction of Na with In the Al-AlClj-Hj or AlClj-NaCl-Hj reductant systems, intermediate alanes AlH Clj, are the active reductant. 

The Rocky Flats Plant (RFP) has a large recovery facility to recover plutonium from miscellaneous scraps and residues a byproduct in the plutonium recovery stream is americium from the decay of plutonium-241. Currently a NaCl-KCl-MgClo eutectic salt is used at Rocky Flats to separate americium from plutonium in a molten salt extraction (MSE) process. 

Molten eutectic salt mixtures have been reported to be active catalysts in graphite and coal char gasification [4, 5]. A major reason probably is the contact between soot and catalyst which is increased by wetting of the soot with the catalyst. 

An exploratory study was carried out with respect to the performance of molten salts as diesel soot oxidation catalyst. The activity of two binary eutectic salts, with a low melting point, was measured and compared with the activity of two very active solid single oxides. Also the influence of NO on the oxidation rate was investigated. 

The use of a liquid catalyst is new in the field of exhaust gas cleaning and there are many unanswered questions and unsolved problems. In this exploratory work, it will be shown that the application of molten eutectic salt mixtures as liquid catalysts might result in sufficiently... 

In earlier work, [1, 2] it has been shown that the contact between soot and catalyst is crucial for the performance of the catalyst. McKee et al. reported that eutectic salt mixtures can be more active than their individual pure components in the catalysed gasification of graphite and coal char [3]. McKee also reported that the activity of a eutectic mixture increases dramatically above the melting point [4] and argued that this was caused by migration of the small salt droplets over the carbon surface. 

Two long-term tests have been performed with copper sulfide electrodes, one in a small investigative cell of the type shown in Figure 1, the other in a sealed 25-W-hr cell which will be described later. The starting active material in both cells was CuS. In both cases, the lithium electrodes consisted of porous metal plates impregnated with molten lithium metal. The electrolyte was the LiCl-KCl eutectic salt mixture, saturated with Li2S and maintained at 380-400°C. 

Figure 5, Gas chromatograms of Rexco coal-tar recorded on glass column with eutectic salt on Chromosorb. Key a, total alkanes and b, branched cyclic alkanes following molecular-sieve removal of most of the n-alkanes.

Figure 6-11 shows Ce02 nanoparticles synthesized by this technique at 1073 K with the addition of the eutectic salts of sodium and potassium nitrate to the precursor solution prior to the aerosol decomposition [89]. The particles are composed of isolated nanoparticles whose mean size was 51 nm. 

Eutectic Salts - Sait mixtures with potential applications as solar thermal energy storage materials. 

The heat of the reaction is removed by means of an eutectic salt bath of potassium nitrate/sodium nitrite (59%/41%) with a melting point of around 141 °C and is used to generate high pressure steam. 

Although mercury was initially used in high temperature processes as a coolant, from 1940 onwards the eutectic salt mixture of potassium nitrate and sodium nitrite has been used as a substitute. 

E. L. Compere, H. C. Savage, and J. M. Baker, High Intensity Gamma Irradiation of Molten Salt Fluoroborate-Sodium Fluoride Eutectic Salt, J. of Nuclear Materials, 34(1), 97 (1970). 

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