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用热重分析(TG),差热分析(DTA),傅里叶红外光谱分析(FTIR)和X射线衍射(XRD)等方法研究了Nd(C2H5CO2)3.H2O的热分解性质。在流动的Ar气中加热到1200℃,水合丙酸钕的分解可以分成6个步骤。在经过脱水反应之后,Nd(C2H5CO2)3首先在250℃和292℃之间生成Nd2(C2H5CO2)4.CO3并释放出二乙基甲酮。当温度升高到315℃,伴随着CO2气体的放出,Nd(C2H5CO2)3立即分解成Nd2O(C2H5CO2)4。在424℃之前,伴随着二乙基甲酮和CO2气体产生,Nd2O(C2H5CO2)4首先分解成中间相Nd2O(CO3)2,并立即转化成分解产物Nd2O2CO3。随着温度升高到770℃,含Nd化合物完全转化成Nd2O3。研究表明,Nd(C2H5CO2)3.H2O在空气中的TG曲线和其在Ar气中的没有任何改变。但是,分解产物二乙基甲酮气体在空气中的燃烧会产生很强的放热效应。与其它稀土金属丙酸盐的热分解的研究结果比较而言,Nd(C2H5CO2)3.H2O的分解性质表现出一些有趣的特点。特别是,在其它丙酸盐中没有发现类似中间相Nd2(C2H5CO2)4.CO3的生成的情况。
The thermal decomposition properties of Nd (C2H5CO2) 3.H2O were investigated by TG, DTA, FTIR and XRD. Heating in flowing Ar gas to 1200 ° C, the decomposition of hydrated neodymium propionate can be divided into six steps. After the dehydration reaction, Nd (C2H5CO2) 3 first generates Nd2 (C2H5CO2) 4CO3 between 250 ° C and 292 ° C and releases diethyl ketone. Nd (C2H5CO2) 3 decomposes to Nd2O (C2H5CO2) 4 immediately as the temperature rises to 315 ° C with the evolution of CO2 gas. Nd2O (C2H5CO2) 4 first decomposed into Nd2O3 (CO3) 2 mesophase with the generation of diethylmethanone and CO2 gas at 424 ℃ and was immediately converted into the decomposition product Nd2O2CO3. As the temperature rises to 770 ° C, the Nd-containing compound is completely converted to Nd2O3. Studies have shown that the TG curve of Nd (C2H5CO2) 3.H2O in air does not change in Ar gas. However, the decomposition product of diethyl ketone gas combustion in the air will have a strong exothermic effect. The decomposition of Nd (C2H5CO2) 3.H2O shows some interesting features in comparison with the results of the thermal decomposition of other rare earth metal propionates. In particular, no formation of a similar mesophase Nd2 (C2H5CO2) 4CO3 was found in other propionates.