IPEX Solutions has made excellent further progress with process developments for recovery of metals from petroleum refinery residues. Attractive economics have been confirmed for leaching recoveries of >90% at bench and bulk scales. A matrix of parameters was explored to find cost-optimal conditions. These included fly ash comminution, alternative lixiviants, leach temperatures and times.
Current efforts are focussed on hydrometallurgical purification and concentration of leached vanadium and nickel values by laboratory scale ion exchange to produce high-purity pregnant solutions suitable for premium grade products including VRB electrolyte.
The following image shows one of more than one hundred leach trials conducted to explore optimal leach conditions.
Hot plate magnetic stirrer and fly ash leach
Pregnant leach solution is separated from fly ash tailings using a Buchner vacuum filter. Continuous solid-liquid separation will be required for a commercial scale operation.
Buchner filter with blue vanadium solution
These investigations are expected to benefit from ongoing parallel refinements of IPEX SMB IX technology aimed at premium grade vanadium product at >99.9% purity.