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Nickel Boride (other)
Nickel boride Nickel boride is the common name of materials composed chiefly of the elements nickel and boron that are widely used as catalysts in organic chemistry. Their approximate chemical composition is Ni2.5B, and they are often incorrectly denoted "" in ... is the common name of material composed chiefly of the elements nickel and boron that are widely used as catalysts in organic chemistry. Nickel boride may also refer to: * Dinickel boride (Ni2B) * Trinickel boride (Ni3B) {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel Boride
Nickel boride is the common name of materials composed chiefly of the elements nickel and boron that are widely used as catalysts in organic chemistry. Their approximate chemical composition is Ni2.5B, and they are often incorrectly denoted "" in organic chemistry publications. Nickel boride catalysts are typically prepared by reacting a salt of nickel with sodium borohydride. The composition and properties vary depending on the specific preparation method. The two most common forms, described and evaluated in detail by Herbert C. Brown and Charles Allan Brown in 1963, are known as P−1 nickel and P−2 nickel. These catalysts are usually obtained as black granules (P−1) or colloidal suspensions (P−2). They are air-stable, non-magnetic and non-pyrophoric, but slowly react with water to form nickel hydroxide . They are insoluble in all solvents, but react with concentrated mineral acids. They are claimed to be more effective hydrogenation catalysts than Raney nickel. Histo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinickel Boride
Dinickel boride is a chemical compound of nickel and boron with formula . It is one of the borides of nickel. The formula "" and the name "nickel boride" are often used for a nickel-boron catalyst obtained by reacting nickel salts with sodium borohydride. However, that product is not a well-defined compound, and its bulk formula is closer to (sic). Synthesis Dinickel boride can be obtained (together with other nickel borides) by heating sodium borohydride with powdered nickel metal up to 670 °C in a closed vessel, so that the released hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, an ... creates a pressure of up to 3.4 MPa. The main reactions can be summarized as : 2 ↔ 2NaH + : 2Ni + 2 + NaH ↔ + 3 + 2 + Na but other reactions occur, yielding other borides. Se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
