Niobium oxide trichloride

Another method of purifying niobium is by distillation of the anhydrous mixed chlorides (29). Niobium and tantalum pentachlorides boil within about 15°C of one another which makes control of the process difficult. Additionally, process materials must withstand the corrosion effects of the chloride. The system must be kept meticulously anhydrous and air-free to avoid plugging resulting from the formation of niobium oxide trichloride, NbOQ. Distillation has been used commercially in the past. 

Niobium Pent chloride. Niobium pentachloride can be prepared in a variety of ways but most easily by direct chlorination of niobium metal. The reaction takes place at 300—350°C. Chlorination of a niobium pentoxide—carbon mixture also yields the pentachloride however, generally the latter is contaminated with niobium oxide trichloride. The pentachloride is a lemon-yeUow crystalline soHd that melts to a red-orange Hquid and hydrolyzes readily to hydrochloric acid and niobic acid. It is soluble in concentrated hydrochloric and sulfuric acids, sulfur monochloride, and many organic solvents. 

Niobium Oxide Trichloride. Niobium oxide trichloride, NbOCl, also can be prepared in a variety of ways, ie, oxidation of the... 

The pentachloride also may be made by chlorination of niobium pentoxide in the presence of carbon at 300°C. The products, however, contain small amounts of niobium oxide trichloride, NbOCls. 

Niobium pentoxide reacts with hydrogen chloride gas at 400 to 700°C to form niobium oxide trichloride, NbOCls [13597-20-1] ... 

Pentaoxide also reacts with niobium pentachloride at elevated temperatures, forming the oxide trichloride ... 

Numerous methods have been described for the preparation of niobium(V) chloride, among them the reaction of niobium(V) oxide with thionyl chloride in a sealed system. In such a procedure some niobium(V) oxide trichloride, NbOCls, is almost always formed, and it is difficult to obtain the pentachloride completely free from this impurity, even by repeated sublimation. The simple, efficient method described here consists in allowing hydrous niobium(V) oxide to react with thionyl chloride at room temperature. Almost quantitative conversion is observed, the pentachloride dissolving in the thionyl chloride, from which it may be recovered, free of oxide trichloride, by vacuum evaporation... 

Niobium(V) oxide trichloride is a significant impurity in niobium(V) chloride, which is used for the preparation of niobium metal. Indeed oxygen impurities in the high-purity niobium produced in this way originate largely with NbOCl 3, and the feasibility of its removal by phosgene treatment has been examined between 380 and 450 C [223,224] ... 

Tungsten(VI) oxide tetrachloride is a common impurity in tungsten(VI) chloride. By anaiogy with niobium(V) oxide trichloride (Section 9.2.2), phosgene might have been expected to convert WOCi to WClj, according to ... 

One method of separating niobium from tantalum is to pass a gaseous mixture of niobium(V) chloride and tantalum(V) chloride over adjacent beds of calcium oxide and calcium fluoride the niobium emerges as volatile niobium(V) oxide trichloride whilst the tantalum is trapped in the CaO and CaFj beds. The reactions postulated to be responsible for trapping tantalum are [1984b] ... 

The oxychloride is volatile and enters the second reduction stage along with the pentachloride. At about 500°C it tends to be reduced to niobium oxide, which deposits with the trichloride, i.e. 

Chlorination of ferroalloys (ferroniobium-tantalum) is a more economical and simple alternative [30]. The process is performed on a sodium chloride melt that contains iron trichloride, FeCU. Chlorine is passed through the melt yielding NaFeCl4, which interacts as a chlorination agent with the Fe-Nb-Ta alloy. Chlorination of ferroalloys allows for the production of pure tantalum and niobium pentachlorides, which are used further in the production of high purity oxides and other products. 

Manganese trichloride oxide, 4141 Mercury(I) oxide , 4613 Mercury(II) oxide, 4605 Molybdenum(IV) oxide, 4716 Molybdenum(VI) oxide, 4717 Nickel(II) oxide, 4821 Nickel(III) oxide, 4823 Nickel(IV) oxide, 4822 Niobium(V) oxide, 4818 Osmium(IV) oxide, 4833 Osmium(VIII) oxide, 4858 Palladium(II) oxide, 4825 Palladium(III) oxide, 4848 Palladium(IV) oxide, 4835... 

Oxidizer, Poison, Corrosive SAFETY PROFILE Poisonous and corrosive. Very reactive, a powerful oxidizer. Explosive or violent reaction with organic materials, water, acetone, ammonium halides, antimony, antimony trichloride oxide, arsenic, benzene, boron, bromine, carbon, carbon monoxide, carbon tetrachloride, carbon tetraiodide, chloromethane, cobalt, ether, halogens, iodine, powdered molybdenum, niobium, 2-pentanone, phosphoms, potassium hexachloroplatinate, pyridine, silicon, silicone grease, sulfur, tantalum, tin dichloride, titanium, toluene, vanadium, uranium, uranium hexafluoride. 

NaAISI206 JADEITE 1134 NbOCI3 NIOBIUM TRICHLORIDE OXIDE 1176... 

NaAISI206[D] DEHYDRATED ANALCITE 1134 NbOCI3[g] NIOBIUM TRICHLORIDE OXIDE (GAS) 1177... 

The first group 5 cyclopentadienyl complexes with a pendant phosphane ligand were reported very recently by Fryzuk. Ligands 35 and 36 were treated with NbCl3(DME) to give niobium bischelates 207 and 208 in 80% yield (Scheme 35). Carbonylation gave 209 and 210 in 80% yield both were characterized by X-ray structure analyses. Oxidation with PbCL resulted in formation of trichlorides 211 and 212, which can also be obtained from the anionic ligands by treatment with Nb(0)Cl3(THF)2 (Scheme 36). 211 was structurally characterized. ... 

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