应用水滑石实时合成分离模拟核素钕

应用水滑石实时合成的方法从高放废液中分离模拟放射性核素钕,通过酸碱滴定、单因素试验及X-射线衍射(XRD)研究确定了最佳分离条件,用红外光谱(FT-IR)、扫描电镜(SEM)、透射电镜(TEM)等对合成的含钕水滑石的结构、形貌进行了分析. 结果表明:模拟放射性核素钕的最佳分离条件,初始ρ(Nd3+)为150 mg/L,pH为10,n(Mg)/［n(Al)+n(Nd)］为3,在该条件下5次平行试验钕的去除率平均值为96.40%,并且钕嵌入到了水滑石的晶格中,合成的含钕水滑石形貌大多为层状六边形；含钕水滑石煅烧产物主要为尖晶石,煅烧产物中未见氧化钕相,表明嵌入到水滑石晶格中的钕在煅烧后仍存在于尖晶石的晶体结构中. 

Separation of Simulated Nuclide Neodymium Using In-Situ Hydrotalcite Synthesis

The simulated radionuclide neodymium was separated from high-level liquid waste using in-situ hydrotalcite synthesis. The optimum conditions of removal of neodymium were determined by the single factor test, acid-base titration and XRD analysis. The structure and morphology of Nd-containing hydrotalcite were analysed by FT-IR, SEM and TEM. The results showed that the optimum conditions of separation were initial Nd3+ concentration below 150 mg/L, pH equal to 10 and Mg/(Al+Nd) molar ratio equal to 3. Under these conditions, the neodymium removal rate was 96.40% by the parallel test. Nd was embedded into the crystal lattice of hydrotalcite, and the main morphology of the Nd-containing hydrotalcite was a layered hexagonal shape. The major calcined product of Nd-containing hydrotalcite was spinel. Nd₂O3 was not observed, which indicated that after calcination, the Nd embedded into the crystal lattice of hydrotalcite still existed in the spinel structure.