SOHIO process legacy waste treatment: Uranium recovery using ion exchange

[Display omitted] •Greater than 98% uranium loading under batch conditions from sulfate media.•Rapid uranium removal from industrially relevant effluent.•Efficient leach and re-generation of MTS957 IXR via mixed carbonate/sulfate eluent.•Process enables treatment of legacy problematic uranium containing waste.•MTS957 application as an effluent polisher or in the event of mal-operation proposed. The feasibility of employing ion-exchange resins for the selective removal of uranium from a complex waste effluent has been investigated. The source of the effluent is a treatment process to reduce the volume of a spent uranium containing catalyst prior to its immobilisation and disposal in South Korea. Commercial anion exchange and chelation resins have been screened, along with an in-house synthesized polyamine functionalized resin. The Langmuir isotherm model produced the best fit for UO22+ binding to all resins, with Purolite MTS957, a mixed sulfonic/phosphonic acid functionalised resin, showing the highest equilibrium adsorption capacity for UO22+, 96.15mgg−1. The Modified Dose-Response Model was found to adequately represent breakthrough across all flow rates used and for all resins tested under dynamic testing conditions. The maximum uranium loading capacities under dynamic conditions for simulant and real wastes were established as 131.52mgg−1 and 68.62mgg−1, respectively. Purolite MTS957 effectively decontaminated the real effluent to uranium levels below the Korean release limit of 1mgL−1. Over 99.9% uranium was successfully eluted from the resin bed in under 20 BV with a mixed sodium carbonate/sulfate eluent.