Palladium black

Palladium black is a coarse, sponge-like form of elemental palladium which offers a large surface area for catalytic activity. It is used in organic synthesis as a catalyst for hydrogenation reactions.[1]

Palladium black
Names
IUPAC name
Palladium
Other names
Palladium black
Identifiers
3D model (JSmol)
EC Number
  • 231-115-6
UNII
Properties
Pd
Molar mass 106.42
Appearance Black powder
Solubility Organic Solvents
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

The term palladium black is also used colloquially to refer to a black precipitate of elemental palladium, which forms via decomposition of various palladium complexes[2].

Preparation

Palladium black is typically prepared from palladium(II) chloride or palladium(II)-ammonium chloride.[1] The palladium chloride process entails the formation of palladium hydroxide using lithium hydroxide followed by reduction under hydrogen gas[3] while the palladium(II)-ammonium chloride route employs a solution formic acid followed by the precipitation of the catalyst using potassium hydroxide.[4]

See also

References
  1. Nishimura, Shigeo (2001). Handbook of Heterogeneous Catalytic Hydrogenation for Organic Synthesis (1st ed.). Newyork: Wiley-Interscience. pp. 34–35. ISBN 9780471396987.
  2. Iwasawa, Tetsuo; Tokunaga, Makoto; Obora, Yasushi; Tsuji, Yasushi (2004-06-01). "Homogeneous Palladium Catalyst Suppressing Pd Black Formation in Air Oxidation of Alcohols". Journal of the American Chemical Society. 126 (21): 6554–6555. doi:10.1021/ja031936l. ISSN 0002-7863. PMID 15161274.
  3. Nishimura, Shigeo; Itaya, Takashi; Shiota, Michio (1967). "Reactions of cycloalkanones in the presence of platinum-metal catalysts and hydrogen". Chemical Communications (London) (9): 422–423. doi:10.1039/C19670000422.
  4. Zelinsky, N.; Glinka, N. (1911). "Über gleichzeitige Reduktions- und Oxydationskatalyse" (PDF). Berichte der Deutschen Chemischen Gesellschaft. 44 (3): 2305–2311. doi:10.1002/cber.19110440347.
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