Bismuth chloride, molten

Mayer SW, Yosim SJ, Topol LE (1960) Cryoscopic studies in the molten bismuth- bismuth chloride system. J Phys Chem 64 238-240... 

This bismuth—calcium—magnesium dross also contains lead that must be removed. The dross is heated in a ketde to free any entrapped lead that melts and forms a pool under the dross. This lead is cast and returned to the bismuth separation cycle. The dross is then melted and treated with chlorine and/or lead chloride to remove the calcium and magnesium. The resulting molten metal is an alloy of bismuth and lead, high in bismuth which is then treated to produce refined bismuth metal. 

Bismuth Trichloride. Bismuth(III) chloride is a colodess, crystalline, dehquescent soHd made up of pyramidal molecules (19). The nearest intermolecular Bi—Cl distances are 0.3216 nm and 0.3450 nm. The density of the soHd is 4.75 g/mL and that of the Hquid at 254°C is 3.851 g/mL. The vapor density corresponds to that of the monomeric species. The compound is monomeric in dilute ether solutions, but association occurs at concentrations greater than 0.1 Af. The electrical conductivity of molten BiCl is of the same order of magnitude as that found for ionic substances. 

Miller A process for purifying and removing silver from gold by passing chlorine gas through the molten metal, covered with borax. The silver forms silver chloride, which floats to the top. Bismuth, antimony, and arsenic are eliminated as their volatile chlorides. Developed by F. B. Miller at the Sydney Mint in Australia in 1867 and soon in world-wide use. 

Bismuth reacts with chlorine, bromine and iodine vapors forming chloride, bromide and iodide of the metal, respectively. Molten bismuth and sulfur combine to form bismuth sulfide, Bi2S3. 

BETTERTON-KROLL PROCESS. A process for obtaining bismuth and purifying desilverized lead that contains bismuth. Metallic calcium or magnesium is added to the molten lead to cause formation of high-melting intennetaHic compounds with bismuth. These separate as a surface scum and are skimmed off. The excess calcium and magnesium are removed from the lead by use of chlorine gas as mixed molten chlorides of lead or zinc. Bismuth of 99.995% purity is produced in this way. 

Molybdates of the Rare Earth Metals. —Salts of the type M2(Mo04)3 have been described. The cerous salt is obtained as yellow crystals by fusing together anhydrous cerous chloride and sodium molybdate. The density of the molten salt is 4-56. The crystals are similar to those of lead and bismuth molybdates, as also are those of didymium molybdate. ... 

Heerman L, OUeslager WD (1991) Electrochemistry of bismuth in a 67 mole% alcl3-33 mole% n-(n-butyl)pyridinium chloride room temperature molten salt. J Electrochem Soc 138 1372-1376... 

J.A. Duffy and M.D. Ingram, Lewis Acid-Base Interactions in Inorganic Oxyacids, Molten Salts and Glasses. III. Co-ordination Studies of Thallium, Lead and Bismuth in Sulphate/Chloride/Bromide Glass Systems, J. Inorg. Nucl. Chem. 36 (1974) 43-47. 

Distribution coefficients may be further modified and operating temperatures reduced by dissolving uranium fuel in a low-melting metal such as bismuth or zinc. Separation of uranium from fission products by liquid extraction between molten bismuth and fused chlorides was extensively studied at Brookhaven National Laboratory [D5] in connection with the liquid-metal fuel reactor (LMFR), which used a dilute solution of in bismuth as fuel. Extraction of fission products from molten plutonium by fused chlorides was studied at Los Alamos [L2] in connection with the LAMPRE reactor. 

Bonds to Halogens.— Two lines with markedly different temperature coefficients are observed in the C1 n.q.r. spectra of solid bismuth trichloride, probably as a result of volume effects associated with different intermolecular bonding. The Raman spectra of the solid and molten trichloride are markedly different, and the latter is best interpreted in terms of the presence of discrete molecules with symmetry. Addition of varying amounts of potassium or caesium chlorides gives BiCl and BiCl, with C v and Oj symmetry, respectively, but AICI4 ions are not produced when aluminium chloride is added, and the melt consists of BiCl3 and AI2CI8. 

In a separate series of experiments the speciation of niobium was studied using exchange reactions of metallic niobium with bismuth, silver or nickel ions in NaCl-KCl melts. The starting NaCl-KCl-BiC melt was prepared by chlorinating bismuth metal (>98%, Reahim) by chlorine gas in the molten salt mixture. Nickel and silver chloride-containing melts were prepared by dissolving anhydrous nickel chloride (98%, Aldrich) and silver chloride (99%, Aldrich), respectively, in NaCl-KCl with HCl gas bubbled through the electrolyte for 2 h to eliminate traces of absorbed moisture. 

Bichloride of mercury (see Mercuric chloride) Bichromates (dichromates) - 663 Biocide -185 Biological solutions - 884 Bismuth carbonate - 28,54,114,124,149,152, 154.156, 253, 264, 393, 398,811,824 Bismuth-lead eutectic, molten - 642, 673, 736 Bismuth, molten - 642, 646, 732, 736 Bismuth nitrate - 613 Bismuth oxycarbonate - 824 Bismuth subcarbonate - 824 Bisulfite in scrubber -109 Bitter almond, oil (see Essential oils)... 

Evidence for Cf(ii) in molten-salt systems has been reported [193]. The distribution coefficient of californium between molten lithium chloride and lithium-bismuth metals at 640°C indicated that divalent californium was present in the salt phase. However, evidence for the existence of Cf(ii) was not found in lithium fluoride-beryllium fluoride melts [193, 194]. 

A modification of this method has been studied in which finely divided thorium from a supernatant mixture of fused chlorides is electrolyti( ally deposited on a molten bi.smuth cathode at the desired temperature [13]. The thorium must be stirred through the interface. Slurries that are satisfactory with respect to thorium content and partiide size and shape have l>een produced by the electrolytic method in batches of up to 10 lb. No e olution of gas has been detected during the thorium-bismuth reaction. 1/iifortunately, the necessary stirring introduces chloride inclu.sions which are difficult to remove completely. Since the.se inclusions would decrea.se... 

The experience in handling salt with larger-sized equipment is quite limited. A small loop built of 347 stainless steel has been operated satisfactorily for a fairly short time. A much larger loop, loop "N, is now being constructed at BNL. This will contact the chloride salt and the bismuth fuel. The. salt part of the loop is constructed of 347 stainless. steel. The bismuth fuel section of the unit is constructed of 2 % Cr-1% Mo steel. The actual contacting units are constructed of both 347 and the low-chrome steels. This pilot plant, when placed in operation, should furnish considerable information on the corrosion characteristics of the molten chloride. salt. 

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