Resistance properties of a macroporous silica-based N,N,N′,N′-tetraoctyl-3-oxapentane-1,5-diamide-impregnated polymeric adsorption material against nitric acid, temperature and γ-irradiation

The resistance of a novel silica-based N,N,N′,N′-tetraoctyl-3-oxapentane-1,5-diamide (TODGA) polymeric adsorption material (TODGA/SiO2-P) against nitric acid, temperature and γ-irradiation had been investigated. The adsorption property of the treated TODGA/SiO2-P was evaluated by a 3 M HNO3 solution containing 0.01 M Nd(III). It was found that both 3 and 0.01 M HNO3 concentrations did not decrease the stability of TODGA/SiO2-P at 25°C. The quantity of TODGA leaked from TODGA/SiO2-P was equivalent to its solubility in the corresponding HNO3 aqueous solution. The effect of 3 M HNO3 on the leakage of TODGA at 80°C was significantly higher than that in 0.01 M HNO3 as well as in all cases at 25°C. The amount of Nd(III) adsorbed towards the treated TODGA/SiO2-P was determined in the range of 0.143-0.148 mmol/g for the HNO3 concentration effect and 0.142-0.0506 mmol/g for the temperature effect. γ-Irradiation showed a more noticeable destruction effect on TODGA/SiO2-P. The content of TODGA leaked increased with an increase in the γ-irradiation dose (ID) from 1.06 to 3.72 MGy in terms of the linear equation [TODGA]=794.5ID+84.0. The amount of Nd(III) adsorbed onto the irradiated TODGA/SiO2-P decreased rapidly from 0.134 to 0.0438 mmol/g, which was lower than 0.153 mmol/g, the adsorption of fresh TODGA/SiO2-P for Nd(III), according to the equation QNd(III)=−0.0301ID+0.160, showing that a large quantity of TODGA leaked from TODGA/SiO2-P. The adsorbed amount of Nd(III) decreased obviously in this order: the HNO3 concentration effect, temperature effect and γ-irradiation.