Magnesium economic importance

The ease of oxidation of magnesium is important in the commercial manufacture of titanium metal. Titanium, when quite pure, shows great promise as a structural metal, but the economics of production have thus far inhibited its use. One of the processes currently used, the Kroll process, involves the reduction of liquid titanium tetrachloride with molten metallic magnesium ... 

The United States and Turkey are the world s largest producers of boron.1 Economically important sources are from the ores rasorite (kernite) and tincal, which are both found in the Mojave Desert of California, with borax being the most important source there. The famous 20-Mule-Team Borax, now a part of chemistry folklore, originates from the time when teams of 20 mules used to haul colemanite from Furnace Creek in Death Valley 166 miles south to Mojave. Elemental boron in its impure form can be obtained by the reduction of the oxide B203 by magnesium, and in the pure form by the reduction of BC13 by hydrogen on hot filaments.1... 

For many industrial-scale operations involving the oxidation or reduction of both inorganic and organic substances, and especially for the production of the more active metals such as sodium, calcium, magnesium, and aluminum, the most cost-effective reducing agent is electrons supplied by an external power source. The two most economically important of these processes are described below. 

Economic Importance Magnesium oxide is, after magnesium carbonate, the industrially most important magnesium compound. Worldwide production in 1995 was ca. 5 10 t, with an additional 1 10 t from seawater and brines. 

Economic Importance Since the manufacture of magnesium chloride is closely linked with the manufacture of metallic magnesium, it follows developments in this sector. In the mid-1970 s ca. 600 10 t/a of magnesium chloride was produced in the Western World, whereas it was ca. 520 10 t/a in 1996. 

Economic Importance. The worldwide production of magnesium sulfate products including potassium magnesium sulfate (fertilizer) was 3.4 10 t/a in the mid-1970 s of which 2.3 10 t was kieserite MgS04 H2O (a byproduct of the potash industry). The main producer countries are the USA and the Federal Republic of Germany. The USA consumption in 1996 excluding natural kieserite was 57-10 t. 

Insular phosphates of two different types exist, depending on whether guano interacts with igneous rocks of intermediate or basic types, or whether such action is confined to calcareous accumulation — such as coral. The first type, which will now be discussed, has more diversified mineralogical compositions. Rock phosphates of magnesium, aluminium and iron comprise less extensive deposits than phosphorites and, consequently, are of less economic importance. 

Phosphorus is technologically and economically important in aluminium-silicon alloys. On one hand it regulates the mechanism of solidification of eutectic (12.5 % Si) and nearly eutectic alloys, on the other hand it grain refines the primary silicon in the hypereutectic system (15-25 % Si) When the eutectic or nearly eutectic aluminium-silicon alloys contain less than 5 Mg/g of phosphorus, the alloy solidifies into a lamellar structure. When the phosphorus concentration is above 9 Mg/g a globular structure is obtained. In hypoeutectic alloys with about 7 % of silicon, the solidification is only fine lamellarly at phosphorus contents between 2 ig/g and 4 g/g. When magnesium is present, even below 2 ng/g a globular structure is obtained. 

Recovery from Brines. Natural lithium brines are predominately chloride brines varying widely in composition. The economical recovery of lithium from such sources depends not only on the lithium content but on the concentration of interfering ions, especially calcium and magnesium. If the magnesium content is low, its removal by lime precipitation is feasible. Location and avadabiHty of solar evaporation (qv) are also important factors. 

One of the economically most important areas in the control of plant processes is defoliation—the intentional removal of leaves. Large quantities of several chemicals currently are employed for this purpose, including magnesium chlorate and DEF (S,SyS-tributyl phosphor otrithioate), and the principal commercial value is for defoliation of cotton. Several synthetics such as 4-chlorophenoxyacetic acid and naphthalene-1-acetic acid are used to provide the opposite but related effect of retarding or limiting fruit drop in apples, stone fruits, and grapes. 

The extraction of metals fundamentally relies on their availability in nature. Three terms are important while one refers to availability. One is the crustal abundance and the other two are the terms resources and reserves. The average crustal abundance of the most abundant metals, aluminum, iron and magnesium, are 8.1%, 5.0% and 2.1% respectively. Among the rare metals titanium is the most abundant, constituting 0.53% of the Earth s crust No metal can be economically extracted from a source in which its concentration is the same... 

Abstract. Grignard reactions are of utmost importance in organic synthesis (Lee, 2005), and finding the prime conditions under which to conduct these reactions is really crucial to their usefulness. This work looks at the effects of time, and temperature on yield in the reaction of isopropyl magnesium bromide with 4-methoxyben-zaldehyde to produce l-(4-methoxyphenyl)-2-methylpropan-l-ol. The reaction was first run for 10 min at 25, 50, 75, and 80 °C. Next it was run at 80 °C for 10, 20, and 30 min (see Methods section for more details). Highest yields (85%) were obtained at 80 °C with 10-20 min reaction times. Utilizing conditions that optimize yields will improve the economic practicality of these reactions, and increase their usefulness as a synthetic tool. 

The world s oceans hold 1.37x10 of water (97.2% of the total amount of water of the hydrosphere). They cover 71% of the earth s surface, are actually the biggest reservoir on our planet, and contain many important minerals. The overall content of mineral matter in the oceans is estimated to be about 5 x 10 tons [1,2]. The seas contain virtually all of the naturally occurring elements and are the only universal source of mineral wealth that is available to most nations. For some of them it is the only source. Yet, most of the elements, the microelements, are available in very low concentrations, i.e., in parts per billion (ppb). The products being extracted from seawater with economic profit at present are sodium chloride, magnesium compounds, and bromine [2-4]. During the last two decades there has been growing interest in the possibility of commercial recovery of additional minerals from seawater [5] and brines [6]. 

Some important biogenic elements, such as phosphorus,caIcium and magnesium, have their own characteristic sedimentation cycle. In this type of cycle, elements from biological systems are continuously lost due to erosion and excessive use in economic activities (e.g. phosphorus in the form of industrial fertilizers, detergents, etc.) and they axe finally stored in the sea. 

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