The influence of nitric, sulfuric and chlorohydric acids on the morphology, composition of elements, structural and chemical transformation of mineral surface and leaching of eudialyte concentrate is studied using a set of the modern analytical techniques. Specific features are revealed in the nature and degree of eudialyte decomposition under the influence of different acids. These features affect the intensity of removal of basic cations of Al, Na, Ca, Mg, K, Ti, Mn, Fe, Sr and Zr from the mineral surface. The behavior and regular patterns in the formation of silica gel and secondary phases during dissolution of eudialyte concentrates are examined. Sulfuric acid, which ensures the highest extraction of Zr and rare earth metals in pregnant solution, contributes to maximum formation of silica gel and considerable quantity of gypsum and insoluble sulfates, which results in high loss of Zr and rare earth metals. The use of nitric and chlorohydric acids reduces the loss of Zr and rare earth metals by 2-5 times.

中文翻译：

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酸对Eudialyte浓缩液浸出中锆和稀土金属提取效率的影响

使用一套现代分析技术研究了硝酸、硫酸和氯氢酸对形态、元素组成、矿物表面的结构和化学转变以及真透析液精矿浸出的影响。在不同酸的影响下，eudialyte 分解的性质和程度揭示了具体特征。这些特征影响从矿物表面去除 Al、Na、Ca、Mg、K、Ti、Mn、Fe、Sr 和 Zr 碱性阳离子的强度。研究了在 eudialyte 浓缩物溶解过程中形成硅胶和第二相的行为和规则模式。硫酸，可确保对富液中 Zr 和稀土金属的最高提取率，有助于最大限度地形成硅胶和大量的石膏和不溶性硫酸盐，从而导致 Zr 和稀土金属的大量损失。硝酸和氯氢酸的使用使Zr和稀土金属的损失减少了2-5倍。