Uranium (VI) Recovery from Black Shale Leaching Solutions Using Ion Exchange: Kinetics and Equilibrium Studies

Abstract

This work studies the removal of uranium ions from chemically leached solutions by sorption using two weak and two strong base anionites. Batch sorption experiments were performed to evaluate the optimum conditions at pH 1.2–2.2, 1.0 g resin dose for 1–12 h contact time at room temperature. These experiments addressed sorption kinetics and sorption isotherm. The maximum sorption capacity reached 55.8 mg/g at room temperature. The kinetics data are well described by the pseudo-second-order kinetic model at initial uranium concentration of 0.62 mg·L−1. To describe sorption kinetics pseudo-first-order, pseudo-second-order and intraparticle diffusion models were proposed. Studies indicated that the sorption of uranium can be fitted by a pseudo-second-order kinetic model very well. Equilibria were described by Langmuir, Freundlich, and Dubinin–Radushkevich equations. The experimental sorption isotherm is successfully described by the Langmuir model.

A Review of In Situ Leaching (ISL) for Uranium Mining

“…The connecting pipelines of the injection and production wells are equipped with header systems, which are linked to the processing plant via trunk lines. Following the extraction of uranium from the production wells, the pregnant solution undergoes specific processing [48,64,65], including uranium recovered by ion exchange, concentration, filtration, and drying. Ultimately, the qualified uranium concentrate, predominantly composed of triuranium octoxide (U 3 O 8 ), known as yellowcake [66], is obtained.…”

Environmental impact of alum shale mining and oil and uranium production in Kvarntorp, Sweden, based on historical archives and environmental monitoring data

“…Some shales are also of interest due to potential metal recovery. Black shale deposits are estimated to be about the 14th most important uranium resource from an economical perspective [10] and there is ongoing research about recovery methods [11].…”