Molybdenite chlorination

Molybdenite is another sulfide ore amenable to processing by chlorination. The reaction between molybdenum disulfide and chlorine, i.e.,... 

Molybdenum pentachloride may be prepared by heating molybdenite in chlorine. Sulfur chloride formed in the reaction is removed by distillation ... 

Molybdenum disulphide is decomposed— yielding the sesquisulphide and molybdenum—only at the temperature of the electric furnace. It is attacked by chlorine, bromine, nitric acid, sulphuric acid, and, when strongly heated, by hydrogen or water-vapour, but not by alkalies. The specific heat of the naturally occurring molybdenite is 0T067 (Neumann), and of the artificial, 0T233 (Regnault). 

I. From molybdenite, the extraction may be made in several ways, (a) The mineral is roasted as long as sulfur dioxide is given off. The residue which contains MoOs is leached with dilute ammonia and the solution evaporated until the ammonium molybdate crystallizes. Japanese patent 37420 (1920) extracts the roasted ore with Na2COj solution, then precipitates calcium molybdate by adding CaCb. (6) The finely ground ore is heated with nitric acid and the MoOj dissolved in ammonia, (c) A current of chlorine is passed over the dry pulverized ore at a temperature of 208°. The molybdenum chloride distills over and may be separated from sulfur and other chlorides by fractional condensation.2 (d) A British patent describes the extraction with an alkaline sulfide or polysulfide solution which removes the molybdenum from the ore as the soluble thio-molybdates. These may be converted to the molybdates by acidification or by contact with more ore. 

Bertrand Pelletier (Bayonne, 30 July 1761-Paris, 21 July 1797 (after inhaling chlorine)) was first an assistant to D Arcet, then an apothecary, finally from 1795 professor in the ficole Polytechnique, and a member of government commissions. He worked on arsenic acid, which he obtained by heating arsenious oxide with ammonium nitrate, the crystallisation of deliquescent salts, chlorine, discovering chlorine hydrate independently of Berthollet (see p. 504), ethers, plumbago and molybdenite, and the preparation of phosphorus and its compounds, including phosphorous acid, phosphoric acid, and hydrogen phosphide (discovered by Gei embre) he was severely burned by an accident with phosphorus, which he showed would bum in air under water. He also published on strontium compounds, the analyses of... 

Iron and manganese occur in a number of soil minerals. Sodium and chlorine (as chloride) occur naturally in soil and are transported as atmospheric particulate matter from marine sprays (see Chapter 10). Some of the other micronutrients and trace elements are found in primary (unweathered) minerals that occur in soil. Boron is substituted isomorphically for Si in some micas and is present in tourmaline, a mineral with the formula NaMg3AlgB3Sig027(0H,F)4. Copper is isomorphically substituted for other elements in feldspars, amphiboles, olivines, p5Toxenes, and micas it also occurs as trace levels of copper sulfides in silicate minerals. Molybdenum occurs as molybdenite (M0S2). Vanadium is isomorphically substituted for Fe or A1 in oxides, pyroxenes, amphiboles, and micas. Zinc is present as the result of isomorphic substitution for Mg, Fe, and Mn in oxides, amphiboles, olivines, and pyroxenes and as trace zinc sulfide in silicates. Other trace elements that occur as specific minerals, sulfide inclusions, or by isomorphic substitution for other elements in minerals are chromium, cobalt, arsenic, selenium, nickel, lead, and cadmium. 

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