To explore the evolution of characteristics of pore structure of a weathered crust elution-deposited rare earth orebody during the leaching process with different valence cations, leaching solutions with NH₄⁺, Mg²⁺, Al³⁺ as cations were prepared to carry out simulated column leaching experiments. Nuclear magnetic resonance (NMR), scanning electron microscope (SEM) and energy dispersive spectrometry (EDS) were used to measure the microscopic characteristics of samples, then the and mechanisms of pore structure evolution of samples during leaching with different valence cations were analyzed. The results showed that: in the main reaction stage, ion displacement reaction in three different leaching solutions resulted in the top-down migration of solid fine particles; then the continuous evolution of secondary pore structure occurred, and then the drainage characteristics of leaching solution were affected. The evolution of pore structure of rare earth orebody induced by leaching solution with different valence cations was generally similar: the pore structure of the orebody firstly evolved from large pores to small pores; whereas at the end of ion exchange, the pore structure evolved from small pores to larger pores. However, there were significant differences in the pore proportion of different sizes. The number of large pores and extra-large pores in the samples of the ammonium sulfate leaching group was the largest, followed by the magnesium sulfate leaching group, and the least were found in the aluminum sulfate leaching group. The mechanism study showed that this difference was caused by the dynamic transformation (deposition and release) of fine particles of rare earth ore on the pore surface, which was affected by the change of ionic strength, the valence cation and the pH value of leaching solution caused by ion substitution.

探讨不同价态阳离子，NH ₄ ⁺，Mg 2 ⁺，Al ^3+的浸出溶液浸出过程中风化硬壳洗脱沉积稀土矿体孔隙结构特征的演变。制备阳离子以进行模拟柱浸出实验。利用核磁共振（NMR），扫描电子显微镜（SEM）和能谱仪（EDS）测量样品的微观特性，分析了不同价阳离子浸出过程中样品的孔结构演变及机理。结果表明：在主要反应阶段，三种不同浸出溶液中的离子置换反应导致固体细颗粒自上而下的迁移；继而发生次生孔隙结构的连续演化，进而影响浸出液的排水特性。不同价阳离子的浸出溶液诱导稀土矿体孔隙结构的演化大致相似：矿体的孔隙结构首先从大孔隙演化为小孔隙。而在离子交换结束时，孔结构从小孔演变为大孔。但是，不同尺寸的孔比例存在显着差异。硫酸铵浸出组样品中大孔和特大孔的数量最多，其次是硫酸镁浸出组，最少的是硫酸铝浸出组。机理研究表明，这种差异是由于孔隙表面上稀土矿细颗粒的动态转变（沉积和释放）引起的，而离子转变，化合价和pH值的变化会影响稀土矿细颗粒的动态转变（沉积和释放）。由离子取代引起。