Abstract

An overview of cobalt compounds including the chemistry exhibited by the +2 and +3 valences is presented emphasizing those compounds of industrial significance. Methods of manufacture for many of the commercial compounds are given as is transition-metal separation methodology. The biological role of cobalt in humans and ruminants is discussed.

The two fluorides of cobalt, namely the cobalt(II) fluoride and the cobalt(III) fluoride, are of great importance in the fluorochemical industry owing to the use of the latter as a hard fluorinating agent. It is used for the replacement of hydrogen by fluorine in halocarbons, fluorination of alkynes, and fluorination of aromatic compounds.

The primary use of cobalt compounds is in catalysis for hydrotreating petroleum resulting in hydrodesulfurization. Cobalt catalysts are also used to denitrify, deoxgenate, crack crude oil and gas, and in homogeneous oxidation and the oxo process (hydroformylation). Cobalt compounds are used in pigments for paints and printing inks, as colorants for glass, ceramics, and enamels, and in the form of metallic soaps as driers. Other industrial uses are in electronics, agriculture as feed and soil additives, and as an adhesive in the tire industry.