Misch metal

Lanthanum is found in rare-earth minerals such as cerite, monazite, allanite, and bastnasite. Monazite and bastnasite are principal ores in which lanthanum occurs in percentages up to 25 percent and 38 percent respectively. Misch metal, used in making lighter flints, contains about 25 percent lanthanum. 

Cerium is a component of misch metal, which is extensively used in the manufacture of pyrophoric alloys for cigarette lighters. While cerium is not radioactive, the impure commercial grade may contain traces of thorium, which is radioactive. The oxide is an important constituent of incandescent gas mantles and is emerging as a hydrocarbon catalyst in self cleaning ovens. In this application it can be incorporated into oven walls to prevent the collection of cooking residues. 

Gr. neos, new, and didymos, twin) In 1841, Mosander, extracted from cerite a new rose-colored oxide, which he believed contained a new element. He named the element didymium, as it was an inseparable twin brother of lanthanum. In 1885 von Welsbach separated didymium into two new elemental components, neodymia and praseodymia, by repeated fractionation of ammonium didymium nitrate. While the free metal is in misch metal, long known and used as a pyrophoric alloy for light flints, the element was not isolated in relatively pure form until 1925. Neodymium is present in misch metal to the extent of about 18%. It is present in the minerals monazite and bastnasite, which are principal sources of rare-earth metals. 

Mischmetal [62379-61-7] Misch metal [8049-20-5] Misch metal hydride Miscible blend Miscible liquids... 

A critical issue is the stabiUty of the hydride electrode in the cell environment. A number of hydride formulations have been developed. Table 5 shows hydride materials that are now the focus of attention. Most of these are Misch metal hydrides containing additions of cobalt, aluminum, or manganese. The hydrides are prepared by making melts of the formulations and then grinding to fine powers. The electrodes are prepared by pasting and or pressing the powders into metal screens or felt. The additives are reported to retard the formation of passive oxide films on the hydrides. 

Cermischmetall, n. mixed metal, misch metal (a mixture of rare-earth metals). 

Figure 16 shows the charge-discharge cycle characteristics of alloys in which part of the nickel component was replaced with cobalt. Misch metal (Mm), which is a mixture of rare earth elements such as lanthanum, cerium, praseodymium, and neodymium, was used in place of lanthanum. It was found that the partial replacement of nickel with cobalt and the substi-... 

N.E. Tran, S.G. Lambrakos, M.A. Imam, Analyses of hydrogen sorption kinetics and thermodynamics of magnesium-misch metal alloy, J. Alloys Compd. 407 (2006) 240-248. 

A commercial mixture of several of the rare-earth elements is called didymium (Di). It is neither an element nor a compound, but is used to name the mixture of oxides and salts of most of the rare-earth elements that are extracted from the ore monazite. Another unique substance, called misch metal, is an alloy of iron and several rare-earth elements (La, Ce, and Pr). This mixture is pyrophoric, which means it sparks when scratched. This is why it is used for cigarette-lighter flints. 

The prices of lanthanide elements are somewhat reasonable and are less than gold per kilogram. (Gold is about 1,800 per kg.) Cesium (Ce), which is relatively common, is often alloyed with La, Nd, and Pr and iron to form misch metal. This alloy has several uses based on its unique ability to spark when scratched. The most common use is as flints for cigarette lighters. 

The compound cerium oxide (either Ce Oj or CeO ) is used to coat the inside of ovens because it was discovered that food cannot stick to oven walls that are coated with cerium oxide. Cerium compounds are used as electrodes in high-intensity lamps and film projectors used by the motion picture industry. Cerium is also used in the manufacturing and polishing of high-refraction lenses for cameras and telescopes and in the manufacture of incandescent lantern mantles. It additionally acts as a chemical reagent, a misch metal, and a chemical catalyst. Cerium halides are an important component of the textile and photographic industries, as an additive to other metals, and in automobile catalytic converters. Cerium is also used as an alloy to make special steel for jet engines, solid-state instruments, and rocket propellants. 

It is used to manufacture safety goggles that filter out strong yellow light (used in welding, for example). Misch metal uses about 5% Pr in the manufacture of cigarette lighter flints. 

Misch metal, an alloy of cerium with other lanthanides is a pyrophoric substance and is used to make gas lighters and ignition devices. Some other applications of the metal or its alloys are in solid state devices rocket propellant compositions as getter in vacuum tubes and as a diluent for plutonium in nuclear fuel. 

PYROPHORIC MATERIAL. Any liquid or solid that will ignite spontaneously in air at about 130F (54.4C). Titanium dichloride and phosphorus are examples of pyrophoric solids tnbutylaluminum and related compounds are pyrophoric liquids. Sodium, butyLithium, and lithium hydride are spontaneously flammable in moist air because they react exothermically with water, Such materials must be stored in an atmosphere of inert gas or under kerosene. Some alloys (barium, misch metal) are called pyrophoric because they spark when slight friclion is applied. 

Cerium, Ce at wt 140.13,at No 58 one of the "rare earth elements gray, ductile, maleable metal which tarnishes in moist air d 6.78 mp 645°, bp 1400° sol in dil acids insol in cold w slowly oxidizes in hot w forms numerous alloys salts. It occurs in monazite sand which is an orthophosphate of thorium and rare earths. Ce-Fe pyrophoric alloys are used as sparking flints for lighters, tracer bullets for military signalling. Ce metal is used as component of some rocket proplnts and in alloys for jet engines. Toxicity, fire expln hazards of Ce are discussed in Ref 5- Ce alloy, called Misch Metal Ce 52, Nd 18, Pr 5, Sm 1 other substances(such as La, Ca, Al, C, Si Fe) 24%, has many applications. Mixt of Ce ... 

Misch metal A manufactured mix of lanthanide elements and iron that easily produces sparks when struck or rubbed. 

These deposits may prove useful for the same purposes as those to which the cerium-iron alloys (Misch Metall) have been adapted. 

An interesting stage in the development of primer mixes was the use of pyrophoric metal alloys, first patented in 1936 and improved in 1964. These rare earth alloys, as used in cigarette lighter flints, give a shower of sparks when lightly scraped. A typical pyrophoric alloy is misch metal, which has the following approximate composition cerium 50%, lanthanum 40%, other rare earth elements 3%, and iron 7%. 

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