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在常温常压下,从近中性的混合铈、镨硝酸盐水溶液中,采用臭氧(或氧气)氧化,制得了红棕色的四价铈镨杂多核氧化物,这种在铈的存在下镨的氧化,拟称为“带同氧化”。通过化学分析,X射线衍射物相分析以及与二氧化锰作用的研究,证明了杂多核氧化物中四价镨的存在。该杂多核氧化物溶于浓硝酸、浓盐酸和冰醋酸中,生成血红色的溶液。通过颜色的变化和紫外可见光谱的研究,考察了四价镨在这些溶液中的稳定性。四价镨在冰醋酸中相当稳定,浓硝酸中一小时内逐渐消失,浓盐酸和硫酸(1:1)中则极不稳定。含四价镨的浓硝酸和冰醋酸溶液的吸收光谱,分别在460nm和440nm处呈现宽带特征吸收峰。通过与不含四价镨的纯铈(Ⅳ)、纯错(Ⅲ)及铈钕混合氧化物等光谱的比较,初步认为这两个特征吸收峰与四价镨的存在有关。
At normal temperature and pressure from the nearly neutral mixed cerium, praseodymium nitrate aqueous solution, the use of ozone (or oxygen) oxidation, the reddish brown tetravalent cerium praseodymium heteropoly oxide obtained in the presence of cerium praseodymium The oxidation, to be called “with the oxidation.” Through the chemical analysis, X-ray diffraction phase analysis and the study of the interaction with manganese dioxide, the presence of tetravalent praseodymium in heteropoly-polynuclear oxides was proved. The heteropoly oxide is dissolved in concentrated nitric acid, concentrated hydrochloric acid and glacial acetic acid to form a blood-red solution. Through the study of color change and UV-visible spectrum, the stability of tetravalent praseodymium in these solutions was investigated. Tetravalent praseodymium in the glacial acetic acid is quite stable, concentrated nitric acid gradually disappear within an hour, concentrated hydrochloric acid and sulfuric acid (1: 1) is very unstable. Absorption spectrum of concentrated nitric acid and glacial acetic acid solution containing tetravalent praseodymium showed broad band characteristic absorption peaks at 460nm and 440nm, respectively. The comparison with the spectra of pure cerium (Ⅳ), pure mist (Ⅲ) and mixed oxides of cerium and neodymium without praseodymium shows that these two characteristic absorption peaks are related to the existence of tetravalent praseodymium.