Abstract:

In order to solve the problems of low beryllium purity, low beryllium yield and large amount of hazardous waste residue in the modern beryllium metallurgy process, the team focused on the basic theories of beryllium metallurgy and proposed a new beryllium extraction method of low-temperature dissociation of beryllium ores plus physical purification of beryllium-containing compounds. For the decontamination process of aluminum-containing fluorides in beryllium ores, the solubility law and purification mechanism of AlF₃ impurities were investigated in the context of the HF system. From the results of the solubility experiments, the concentration of Al³⁺ and the concentration of F^- from the direct dissociation of AlF₃ were very low, at the level of 10^-5, and it was difficult to form the AlF${}_{\mathrm{6}}^{\mathrm{3}-}$ complex. Therefore, the solubility of AlF₃ in the H₂O system was lower than that in the HF system, while under the HF-H₂O-AlF₃ system, the ligand ion of F would be formed so that the originally insoluble AlF₃ had certain solubility instead. Based on this, low-temperature calcination was used to destroy the structure of H₃AlF₆ and decompose H₃AlF₆ into AlF₃, avoiding the effect of H₃AlF₆ on the solubility of AlF₃, and thus solving the separation problem of impurities.

Key words: HF system, beryllium metallurgy, beryl, AlF₃, solubility

摘要：

为了解决现代铍冶金工艺中铍纯度低、铍收得率低以及危废渣量大等难题，本文聚焦铍冶金基础理论，提出了低温解离铍矿+物理纯化含铍化合物的提铍新方法。针对铍矿中含铝氟化物的除杂过程，在HF体系背景下，研究了AlF₃杂质的溶解度规律和纯化机理，从溶解度实验结果来看，AlF₃直接解离出来的Al³⁺浓度和F^-浓度是很低的，在10^-5级别，难以形成AlF${}_{\mathrm{6}}^{\mathrm{3}-}$配合物，所以在H₂O体系中AlF₃的溶解度要低于在HF体系中的溶解度，而在HF-H₂O-AlF₃体系下，会形成F的配位离子，使原本不溶的AlF₃反而有了一定的溶解度。以此为基础，采用低温煅烧的方式破坏H₃AlF₆结构，将H₃AlF₆分解成AlF₃，避免了H₃AlF₆对AlF₃溶解度产生的影响，从而解决了杂质的分离难题。

关键词: 氟化氢体系, 铍冶金, 绿柱石, 氟化铝, 溶解度