Selective separation of Ag(I)/Pd(II) using mesoporous Mn 3 O 4 for 111 Ag production

Mesoporous Mn 3 O 4 was developed as an efficient single-step sorbent for the selective separation of Ag + from Pd 2+ , enabling a practical approach for the production of carrier-free 111 Ag. The material was synthesized via a CTAB-assisted co-precipitation method and characterized using FTIR, XRD, XPS, and EDX techniques. Its performance was evaluated in both batch and column systems. The sorbent, with an average pore size of about 4 nm and a surface area of 24.87 m 2 g −1 , exhibited high adsorption capacities for Ag + of 132 ± 6.6 mg g −1 (batch) and 112 ± 5.5 mg g −1 (column) at pH 3. The separation mechanism is attributed to size-selective mesopore diffusion, facilitated by the smaller hydrated radius of Ag + compared to Pd 2+ , in combination with surface complexation. The material demonstrated excellent chemical stability with negligible manganese leaching. The method was successfully validated for the recovery of 111 Ag from irradiated palladium targets, achieving a yield of 74 % with high radionuclidic purity.