Rhodium(III) nitrate

Rhodium nitrate is a dark orange-brown solution with strong corrosive properties. It remains relatively stable at ambient temperatures but begins to decompose when heated to 255 degrees Celsius. It is insoluble in water but dissolves in ammonia solutions, hydroxides, carbonates, and organic acids such as acetic acid, gluconic acid, citric acid, and malic acid. Its primary application is in the manufacture of various catalysts, including hydrogenation catalysts, oxidation catalysts, desulfurization catalysts, and alkylation catalysts.

It acts as a chemical catalyst, it is used as a slurry bed in Hydrogenation reaction. It is an important raw material and intermediate used in Organic Synthesis, Pharmaceuticals industries.

Rhodium nitrate is prepared by reacting rhodium with nitric acid, or by dissolving rhodium(III) oxide pentahydrate in nitric acid and evaporating the solution to dryness over a water bath.

Rhodium(III) nitrate hydrate can be used as a precursor:
    To synthesize Rh-doped catalysts for various chemical transformations.
    With iron(III) nitrate nonahydrate to synthesis Fe–Rh/TiO2 catalysts for hydrogenation reaction.[1]
    For Ethene Hydroformylation, a bimetallic Rh/Co catalyst is synthesized by combining Rhodium(III) nitrate hydrate with Co(NO3)2 .6H2O.[2]
    For the simultaneous electrodeposition of Cu and Rh from an aqueous nitrate solution.[3]

Not classified

[1] ROBERT M. PALOMINO . The effect of Fe–Rh alloying on CO hydrogenation to C2+ oxygenates[J]. Journal of Catalysis, 2015, 329: Pages 87-94. DOI:10.1016/j.jcat.2015.04.033.
[2] NING HUANG. Insights into the Bimetallic Effects of a RhCo Catalyst for Ethene Hydroformylation: Experimental and DFT Investigations[J]. Industrial & Engineering Chemistry Research, 2020, 59 42: 18771-18780. DOI:10.1021/acs.iecr.0c03437.
[3] DIMITRA ANASTASIADOU. A Study of Cu-Rh Electrodeposition**[J]. ChemElectroChem, 2022, 10 1. DOI:10.1002/celc.202200842.
[4] R. CAMINITI. Structure of rhodium(III) nitrate aqueous solutions. An investigation by x-ray diffraction and Raman spectroscopy[J]. The Journal of Physical Chemistry , 1986, 90 2: 238-243. DOI:10.1021/j100274a007.