Authors : Roger K. M. Rumbu

Volume/Issue : Volume 11 - 2026, Issue 8 - August

Google Scholar : https://tinyurl.com/ycxbmwvz

DOI : https://doi.org/10.38124/ijisrt/26aug1216

Note : A published paper may take 4-5 working days from the publication date to appear in PlumX Metrics, Semantic Scholar, and ResearchGate.

Abstract : Phosphoric-acid treatment is used to remove uranium from selected African Copperbelt cobalt process liquors. This structured critical review develops a comparative decision framework linking uranium-retention mechanisms, phosphorus demand, and cobalt-product acceptance. Industrial accounts, laboratory experiments, dissolution studies, and conceptual process comparisons are appraised separately. The synthesis distinguishes discrete uranyl-phosphate precipitation, adsorption, and incorporation into host solids. It shows why a decrease in filtered uranium does not establish a unique retention mechanism or cobalt selectivity. Calcium-bearing hosts, reagent-derived metals, colloid capture, and uranium already present in seeds change the interpretation of dose and removal. A phosphorus-to-uranium molar ratio of one corresponds conditionally to 0.4117 kg pure H₃PO₄ per kilogram uranium. Sampling-inclusive balances connect this stoichiometric basis to measured transfer, while a downstream balance includes uranium retained in solids, entrained liquor, cobalt yield, and dry or wet product mass. Bicarbonate dissolution evidence makes residue acceptance dependent on exposure chemistry and duration. Economic reconciliation distinguishes reported payback conventions from unresolved reagent-consumption assumptions. The contribution is an evidence-to-decision framework: identify the phosphorus sinks, close uranium and cobalt inventories, discriminate the uranium host, and verify separation and product quality before selecting a site-specific dose.

Keywords : African Copperbelt, Cobalt Liquor, Phosphoric Acid, Uranium, Phosphate Precipitation, Ion Exchange, Mass Balance.

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