Recovery of high purity cobalt from spent ammonia cracker catalyst

With the ever-increasing demand for cobalt in India it is worthwhile exploiting secondary resources. A step in this direction has been taken in our laboratory at BARC by recovering cobalt from spent ammonia cracker catalyst after leaching with sulfuric acid. The removal of Fe3+ and Al3+ from the leach liquor can be achieved by either chemical precipitation or solvent extraction using DEHPA as an organic extractant. When nickel is present as an impurity, it is separated by extraction with LIX 84I. This process has been scaled up and it has been possible to obtain a cobalt recovery of ∼85% with a purity greater than 99.9%.