Molybdenum trioxide

Molybdenum trioxide titration from yellow ppt. M0O3 0.047979... 

Molybdenum trioxide Chlorine trifluoride, interhalogens, metals... 

Molybdenum. The commonly used molybdenum materials are sodium molybdate [7631-95-0] ammonium molybdate [12027-67-7] molybdenum trioxide [1313-27-5] molybdenum sulfate [51016-80-9] and frits. Molybdenum is used in smaller amounts than any of the other micronutrients, ranging from a few grams to 3 kg/hm of Mo. 

Molybdenum trioxide is a condensed-phase flame retardant (26). Its decomposition products ate nonvolatile and tend to increase chat yields. Two parts of molybdic oxide added to flexible poly(vinyl chloride) that contains 30 parts of plasticizer have been shown to increase the chat yield from 9.9 to 23.5%. Ninety percent of the molybdenum was recovered from the chat after the sample was burned. A reaction between the flame retardant and the chlorine to form M0O2 012 H20, a nonvolatile compound, was assumed. This compound was assumed to promote chat formation (26,27). 

Chemical products are produced from technical-grade oxide in two very different ways. Molybdenum trioxide can be purified by a sublimation process because molybdenum trioxide has an appreciable vapor pressure above 650°C, a temperature at which most impurities have very low volatiUty. The alternative process uses wet chemical methods in which the molybdenum oxide is dissolved in ammonium hydroxide, leaving the gangue impurities behind. An ammonium molybdate is crystallized from the resulting solution. The ammonium molybdate can be used either directly or thermally decomposed to produce the pure oxide, MoO. ... 

Manufacturing Processes. Ammonium molybdate or molybdenum trioxide is reduced to molybdenum metal powder by hydrogen in a two-stage process. In the first stage, MoO or ammonium molybdate is reduced to molybdenum dioxide, M0O2, at temperatures around 600°C in the... 

Oxidation Catalysis. The multiple oxidation states available in molybdenum oxide species make these exceUent catalysts in oxidation reactions. The oxidation of methanol (qv) to formaldehyde (qv) is generally carried out commercially on mixed ferric molybdate—molybdenum trioxide catalysts. The oxidation of propylene (qv) to acrolein (77) and the ammoxidation of propylene to acrylonitrile (qv) (78) are each carried out over bismuth—molybdenum oxide catalyst systems. The latter (Sohio) process produces in excess of 3.6 x 10 t/yr of acrylonitrile, which finds use in the production of fibers (qv), elastomers (qv), and water-soluble polymers. 

Chemical Designations - Synonyms Molybdenum trioxide Molybdic anhydride Chemical Formula M0O3... 

The crystal structures observed during the oxidation of molybdenum consist of stable molybdenum dioxide in contact with the metal throughout the range 300-700°C. As the film thickens in the low-temperature range, the trioxide predominates on the surface. At 400°C, molybdenum trioxide is no longer observed and molybdenum dioxide is the only oxide observed. 

Molybdate-strychnine reagent This reagent is prepared in two parts these are mixed just before use, since the addition of the acid molybdate solution to the strychnine sulphate solution produces a precipitate after 24 hours. Solution A (acid molybdate solution) place 30 g molybdenum trioxide in a 500 mL conical flask, add 10 g sodium carbonate and 200 mL water. Boil the mixture until a clear solution is obtained. Filter the hot solution, if necessary. Add 200 mL 5M sulphuric acid, allow to cool, and dilute to 500 mL. 

Molybdenum Trioxide (Molybdenum Anhydride, Moiybdic Oxide, Moiybdic Acid Anhydride). Mo03, mw 143.95, white powd, mp 795°, bp 1155°, d 4.696g/cc at 26/4°, SI sol in w, sol in acids, alk sulfates and amm hydroxide. Prepn is by first boiling coned nitric acid with NH4... 

Molybdenum hexafluoride. 3,1412 Molybdenum-iron-sulfur complexes, 4,241 Molybdenum oxide amino acid formation prebiotic systems, 6, 872 Molybdenum storage protein microorganisms, 6, 681 Molybdenum telluride, 3, 1431 Molybdenum tetraalkoxides physical properties, 2, 347 Molybdenum tribromide, 3,1330 Molybdenum trichloride, 3,1330 Molybdenum trifluoride, 3, 1330 Molybdenum trihalides, 3, 1330 bond lengths, 3, 1330 magnetic moments, 3,1330 preparation, 3,1330 properties, 3, 1330 structure, 3,1330 Molybdenum triiodide, 3,1330 Molybdenum trioxide complexes, 3, 1379 Molybdenum triselenide, 3, 143)... 

After having described molybdenum trioxide, we intend to specify the best finite clusters allowing to represent each of the (010), (001) and (100) faces in order to study surface properties such as energy and electronic distribution. For this purpose, the evolution of the electronic properties will be studied as a function of the cluster size and referred to the results of an EHT - band calculation [12] all calculations have been made with QCPE programs [13,14] and Hoffmann parameters [15],... 

Molybdenum trioxide has a layered structure with orthorhombic symetry [16] (a=3.963, b=ll855, c=3.696 A), this structure consists of double layer sheets parallel to the (010) cleavage plane. The building unit is a distorted M0O6 octahedron, with Mo-0 distances 1.67, 1.73, 1.95 (twice), 2.25 and 2.33 A (Fig.l)... 

Fig. 1 a) Cristallographic structure of orthorhombic molybdenum trioxide M0O3 b) Distorde octahedron M0O6 with different types of oxygen 0, On, Om... 

Molybdenum trioxide gives rise to a violent reaction when it is heated with lithium during which temperatures sometimes reach 1400°C. With sodium or potassium, under the same conditions, the mixture incandesces whereas with magnesium it detonates. 

The reduction of molybdenum trioxide to the metal by hydrogen is also a three-stage process which can be represented as... 

Pure molybdenum trioxide, a higher quality product, is in great demand with regard to chemicals and catalyst manufacturers, superalloy producers, and molybdenum metal producers. This refined quality oxide is produced by the volatilization of the technical grade... 

Aluminium oxide, arsenic trioxide, bismuth trioxide, calcium oxide, chromic oxide, lanthanum oxide, lead dioxide, magnesium oxide, manganese dioxide, molybdenum trioxide, phosphorus pentoxide, stannic oxide, sulfur dioxide (explodes), tantalum pentoxide, tungsten trioxide, vanadium pentoxide. 

Lithium is used to reduce metallic oxides in metallurgical operations, and the reactions, after initiation at moderate temperatures, are violently exothermic and rapid. Chromium(III) oxide reacts at 185°C, reaching 965° similarly molybdenum trioxide (180 to 1400°), niobium pentoxide (320 to 490°), titanium dioxide (200-400 to 1400°), tungsten trioxide (200 to 1030°), vanadium pentoxide (394 to 768°) also iron(II) sulfide (260 to 945°), and manganese tclluridc (230 to 600°C)... 

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