Search results
Results from the WOW.Com Content Network
Tantalum ores often contain significant amounts of niobium, which is itself a valuable metal.As such, both metals are extracted so that they may be sold. The overall process is one of hydrometallurgy and begins with a leaching step; in which the ore is treated with hydrofluoric acid and sulfuric acid to produce water-soluble hydrogen fluorides, such as the heptafluorotantalate.
Tantalum pentoxide (Ta 2 O 5) is the most important compound from the perspective of applications. Oxides of tantalum in lower oxidation states are numerous, including many defect structures, and are lightly studied or poorly characterized. [38] Tantalates, compounds containing [TaO 4] 3− or [TaO 3] − are numerous.
2 H 2 [NbOF 5] + 10 NH 4 OH → Nb 2 O 5 ↓ + 10 NH 4 F + 7 H 2 O. Several methods are used for the reduction to metallic niobium. The electrolysis of a molten mixture of K 2 [NbOF 5] and sodium chloride is one; the other is the reduction of the fluoride with sodium. With this method, a relatively high purity niobium can be obtained.
Many oxides of tantalum are called tantalates. They are viewed as derivatives of "tantalic acid", hypothetic compounds with the formulas Ta 2 O 5 ·nH 2 O [1] or HTaO 3 [2]). Examples of such tantalates are lithium tantalate (LiTaO 3), lutetium tantalate (LuTaO 4), neodymium tantalate (NdTaO 4) and lead scandium tantalate (PST or Pb(Sc x Ta 1-x ...
[4] 2 Ta + 5 Cl 2 → 2 TaCl 5 2 Ta + 10 HCl → 2 TaCl 5 + 5 H 2. It can also be prepared by a reaction between tantalum pentoxide and thionyl chloride at 240 °C Ta 2 O 5 + 5 SOCl 2 → 2 TaCl 5 + 5 SO 2. Tantalum pentachloride is commercially available, however samples can be contaminated with tantalum(V) oxychloride (TaOCl 3), formed by ...
[3]: 1–3 As with any new technology, the earliest exposures are expected to occur among workers conducting research in laboratories and pilot plants, making it important that they work in a manner that is protective of their safety and health. [4]: 1 A risk management system is composed of three parts.
[2] [3] Tantalum boride films can be deposited from a gas mixture of TaCl 5-BCl 3-H 2-Ar in the temperature range 540–800 °C. TaB 2 (single-phase) is deposited at a source gas flow ratio (BCl 3 /TaCl 5) of six and a temperature above 600 °C. TaB (single-phase) is deposited at BCl 3 /TaCl 5 = 2–4 and T = 600–700 °C. [1]
The mineral group tantalite [(Fe, Mn)Ta 2 O 6] is the primary source of the chemical element tantalum, a corrosion (heat and acid) resistant metal. It is chemically similar to columbite , and the two are often grouped together as a semi-singular mineral called coltan or "columbite-tantalite" in many mineral guides.