Extraction chromatographic performance of uranium using XAD-4 loaded with di-2-ethylhexylphosphoric acid and nitrate solutions

Chromatographic extraction of uranium from nitrate medium using di-2-ethylhexylphosphoric acid (HDEHP) loaded on XAD-4 (macroporous styrene divinylbenzene) is investigated. Parameters affecting column performance including flow rate, HDEHP concentration and column dimensions are studied in terms of height equivalent to theoretical plate and break-through capacity. The experimental results are analysed based on the Van Deemter equation. The different constants representing the longitudinal diffusion of the solute in the mobile phase, packing irregularities of the column, and rate of transfer of solute between the stationary and aqueous phases are evaluated and discussed. Optimum conditions for uranium removal from comparable simulated high active waste nitrate solution are studied. (author)