2635. Cupric Chromite

Nomenclature

CAS number: 12018-10-9
Cupric chromate(III).
Cr2CuO4; mol wt 231.54.
Cr 44.91%, Cu 27.44%, O 27.64%.
CuCr2O4.

Description and references

Prepd by heating CuCrO4 at 400°: Stroupe, J. Am. Chem. Soc. 71, 569 (1949); or by decompn of (NH4)2Cu(CrO4)2.2NH3 at 700°: Whipple, Wold, J. Inorg. Nucl. Chem. 24, 23 (1962).

Properties

Grayish-black to black tetragonal crystals. Dec to CuCrO2 and CrO3 above 900°. Practically insol in water, dil acids, concd HCl.

Derivative

Copper-chromium oxide.

Properties

A mixture of CuCr2O4 and CuO formed on decompn at temps below 400°, of orange copper ammonium chromate complex prepd from Cu(NO3)2, Na2Cr2O7 and NH4OH: Adkins et al., J. Am. Chem. Soc. 72, 2626 (1950); Wagner in Handbook of Preparative Inorganic Chemistry vol. 2, G. Brauer, Ed. (Academic Press, New York, 2nd ed., 1965) p 1672. Fine, brownish-black to black powder. Stable in atmospheric O2 and moisture. Practically insol in water, dil acids.

Use

Selective hydrogenation catalysts.