Development of extraction chromatographic adsorbent using alkylpyridinedicarboxyamides as extractant for separation of trivalent minor actinides from lanthanides – stability and separation ability against nitric acid exposure and gamma-ray irradiation

Figures & data

Table 1. Physicochemical properties of XAD4 and Gelpack A040 (25 – 45 μm) resin.

	Specific surface area	Pore volume	Average fine pore diameter	Average particle size
	(m^2 g^−1)	(cm^3 g^−1)	(Å)	(μm)
XAD4	750	0.5	40	250–850
Gelpack A040 (25–45 μm)	519	1.09	84	25–45

Figure 1. Synthetic route to and structure of R-PDA (alkylpyridinedicarboxyamide).

Table 2. Concentrations of R-PDA in prepared adsorbent.

	Oct-PDA	Dec-PDA
	(mmol g^−1)
XAD4	0.64	0.63
Gelpack A040 (25–45 μm)	0.84	–

Figure 2. Stability of Oct-PDA/XAD4 adsorbent against nitric acid exposure.

Figure 3. Residual ratios of Oct-PDA and Dec-PDA in adsorbent irradiated by gamma-rays under the dry irradiation condition.

Figure 4. Distribution coefficients, K_d, of Am(III) and Eu(III) onto Oct-PDA/XAD4 (a) and Dec-PDA/XAD4 (b) irradiated by gamma-rays under the dry irradiation condition.

Figure 5. Residual ratios of Oct-PDA in adsorbent irradiated by gamma-rays under the dry and wet irradiation conditions.

Figure 6. Distribution coefficient, K_d, of Am(III) and Eu(III) onto Oct-PDA/XAD4 irradiated by gamma-rays under the wet irradiation condition.

Figure 7. Influence of the flow rate on the separation of Dy(III) from Eu(III) with Oct-PDA/XAD4. Eluent, 5 M HNO₃; flow rate, 0.2 mL min⁻¹ (a) and 0.8 mL min⁻¹ (b).

Figure 8. Influence of the Eu(III) concentration on the separation of Dy(III) from Eu(III) with Oct-PDA/XAD4. [Dy] = 10 mM, [Eu] = 10 mM (a), 50 mM (b), 100 mM (c): eluent, 5 M HNO₃; flow rate, 0.1 mL min⁻¹.

Figure 9. Influence of the Eu(III) concentration on the separation of Am(III) from Eu(III) with R-PDA/XAD4. Oct-PDA/XAD4, [Am] = [Eu] = tracer (a), Dec-PDA/XAD4, [Am] = [Eu] = tracer (b), Oct-PDA/XAD4, [Am] = tracer, [Eu] = 0.1 M (c): eluent, 5 M HNO₃; flow rate, 0.1 mL min⁻¹.

Figure 10. Elution curves of Am(III) and Eu(III) with Oct-PDA/Gelpack A040 (25–45 μm) adsorbent: eluent, 5 M HNO₃; flow rate, 0.1 mL min⁻¹.