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There are numerous impurities in wet-process phosphoric acid, among which manganese is one of detri-mental metallic impurities, and it causes striking negative effects on the industrial phosphoric acid produc-tion and downstream commodity. This article investigated the adsorption behavior of manganese from phosphoric acid employing Sinco-430 cationic ion-exchange resin. Resorting FT-1R and XPS characteriza-tions, the adsorption mechanism was proved to be that manganese was combined with sulfonic acid group. Several crucial parameters such as temperature, phosphoric acid content and resin dose were stud-ied to optimize adsorption efficiency. Through optimization, removal percentage and sorption capacity of manganese reached 53.12 wt%, 28.34 mg?g-1, respectively. Pseudo-2nd-order kinetic model simulated kinetics data best and the activation energy was evaluated as 6.34 kJ ? mol-1 for the sorption reaction of manganese. In addition, the global adsorption rate was first controlled by film diffusion process and second determined by pore diffusion process. It was found that the resin could adsorb up to 50.24 mg?g-1 for man-ganese. Equilibrium studies showed that Toth adsorption isotherm model fitted best, followed by Temkin and Langmuir adsorption isotherm models. Thermodynamic analysis showed that manganese adsorption was an endothermic process with enhanced randomness and spontaneity.