Recovery of palladium using chemically modified cedar wood powder

3級アミン型架橋杉を利用したパラジウムの分離回収に関する研究

Parajuli, D.; 広田 耕一

Parajuli, D.; Hirota, Koichi

Japanese cedar wood powder (CWP) was chemically modified to tertiary amine type adsorbent and studied for the selective recovery of Pd(II) from various industrial waters. Batch adsorption tests were performed from 0.1 M to 5 M HCl and HNO conditions. The maximum loading capacity for Pd(II) studied in 0.1, 1, 3, and 5 M HCl conditions were evaluated as 1.4, 0.81, 0.36, and 0.26 mol/kg, respectively. And in 3 M HNO condition it was 0.6 mol/kg. Recovery of Pd(II) from real industrial solution was also performed where only Pd(II) was selectively loaded on modified CWP and was recovered using acidic thiourea with about 95 % recovery factor and 75 times preconcentration factor. Since, Pd(II) adsorption was found to be better in HNO, the possibility of its application on the recovery of Palladium from high level liquid waste (HLW) was also studied. For this, simulated HLW prepared in 3 M HNO was used. The adsorption experiment was conducted in normal and in irradiation conditions. Interestingly, selective separation of Pd(II) was achieved with the capacities of 0.47 mol/kg in normal condition and 0.4 mol/kg for adsorption mixture irradiated for 200 h at a dose rate of 10 kGy/h.