Palladium on calcium carbonate

Catalog Number

ACMA00003176

Product Name

Palladium on calcium carbonate

Category

Fuel Cell Catalysts

IUPAC Name

calcium;palladium(2+);dicarbonate

Molecular Weight

266.5g/mol

Molecular Formula

C2CaO6Pd

Canonical SMILES

C(=O)([O-])[O-].C(=O)([O-])[O-].[Ca+2].[Pd+2]

InChI

InChI=1S/2CH₂O3.Ca.Pd/c2*2-1(3)4;;/h2*(H2,2,3,4);;/q;;2*+2/p-4

InChI Key

XGLHAVVVUOEGIO-UHFFFAOYSA-J

Application

Among the platinum group metals, palladium is the least noble metal, exhibiting greater reactivity than other metals of the group. The metal forms mostly bivalent compounds, although a small number of tetravalent and a fewer trivalent compounds are known. Palladium exhibits a strong tendency to form complexes, most of which are four-coordinated square planar complexes of the metal in +2 oxidation state. When heated in air or oxygen above 350°C, palladium forms a black oxide, PdO coated over its surface. On further heating to over 790°C, the oxide decomposes back to the metal. Palladium dissolves more oxygen in molten state than in solid form.

Palladium reacts with fluorine and chlorine at 500°C forming its halides, the black PdF3 and the red deliquescent solid PdCl2.

Palladium is attacked by concentrated nitric acid, particularly in the presence of nitrogen oxides. The reaction is slow in dilute nitric acid. Finely divided palladium metal reacts with warm nitric acid forming palladium(II) nitrate, Pd(NO3)2. Hydrochloric acid has no affect on the metal. Reaction with boiling sulfuric acid yields palladium sulfate, PdSO4, and sulfur dioxide.

Palladium readily dissolves in aqua regia forming chloropalladic acid, H2PdCl6. Evaporation of this solution yields palladium(II) chloride, PdCl2.

Palladium absorbs hydrogen over 800 times its own volume over a range of temperature. By doing so, the metal swells, becoming brittle and cracked. Such absorption of hydrogen decreases the electrical conductivity of the metal. Also, such absorption activates molecular hydrogen, dissociating it to atomic hydrogen.

Storage

In
particular, palladium on carbon should always be handled under an inert atmosphere
(preferably argon), and reaction vessels should be flushed with inert gas before the
catalyst is added. Dry catalyst should never be added to an organic solvent in the
presence of air. Palladium on carbon recovered from catalytic hydrogenation
reactions by filtration requires careful handling because it is usually saturated with
hydrogen and will ignite spontaneously on exposure to air. The filter cake should
never be allowed to dry, and the moist material should be added to a large quantity
of water and disposed of properly.Store at RT.

Complexity

18.8

Covalently-Bonded Unit Count

4

Exact Mass

265.83556g/mol

Formal Charge

0

Heavy Atom Count

10

Monoisotopic Mass

265.83556g/mol

Rotatable Bond Count

0

MSDS

COA

Spec Sheet