Prospective of effective separation of fission palladium using biomass sorbent

Hirota, Koichi; Parajuli, D.; Seko, Noriaki

The adsorbent (CWP-TU) was prepared by heating a 1:2 mixture of cedar wood powder (CWP) and thiourea using a microwave. Because the high level waste is contained basically in nitric acid, the adsorption test was performed in 3 M nitric acid and found that Pd(II) adsorption is preferred. The Pd(II) only selectivity was revealed by taking simulated HLW solution containing 15 different metals in same molar ratio as in the real fission waste. The feasibility of recovering Pd(II) using CWP-TU from highly radioactive HLW solution was tested by irradiating the mixture of adsorbent and simulated HLW solution by rays for 50 h with total dose of 500 kGy. The results show that, unlike on commercial synthetic extractants, there is no direct effect of radiation on the Pd(II) binding ability of the sorbent.