含氯热液流体中锗的溶解度实验研究

锗是当前全球高新科技产业的重要原材料，属于国家重要的战略资源，且需求量近年来大幅度增长，因而其成矿作用研究及找矿勘查均是国际矿床学领域关注的热点。目前，全球锗资源主要来源于铅锌矿和煤矿。研究表明，这些矿床中锗的矿化均与热液流体作用密切相关，且成矿流体多为富氯的中低温热液流体。然而由于缺乏锗在含氯热液流体中的溶解度、络合物种型及相关热力学数据，使得锗在热液成矿过程中的迁移形式、富集及沉淀成矿机制成为锗矿床成因研究中长期备受关注，但一直未得到较好解决的关键科学问题。本项目拟将系统开展锗在含氯热液流体（100-350oC、饱和蒸气压）中的溶解度实验，测定不同物化条件下锗的溶解度，并通过热力学计算确定锗在热液流体中的络合物种型及其形成常数，结合HCh等软件对锗的成矿过程进行模拟，揭示锗在成矿热液流体中的迁移形式、富集及沉淀成矿机制。本研究的开展对深化认识各类矿床中锗的富集及其成矿机制具有重要意义。

Germanium, one of the national and global strategic metals, plays an extremely crucial role in high-tech industries, and so far, no substitutive material has been found to match its properties. Thus, genetic studies of germanium mineralization and its exploration are becoming hot topic of academic front attention. Globally, germanium resources hosted mostly in Pb-Zn deposits and coals, and numerous previous studies shown that the germanium mineralization in these deposits are all closely related to hydrothermal fluid. It is a critical and long-focused issue for study on germanium deposit genesis, however, the migration and super-enrichment mechanism of germanium in hydrothermal solution is still unclear. This is mainly due to the lack of the solubility data and species of aqueous germanium complex, as well as their thermodynamic data. In view of the vital of this problem, in this study, simulation experiments will be carried out, to determine the solubility of Ge in chloride-bearing fluids (100-350 oC, saturated vapor pressure); furthermore, thermodynamic properties will be obtained by the relevant thermodynamic calculation, such as the structures and the formation constants of the main Ge complexes under varying physicochemical conditions; and at last, combining with HCh and Unitherm methods, metallogenic mechanism for the typical germanium deposits will be modeled, and we will further discuss the migration, super-enrichment and deposition mechanism of germanium. Our study will promote better and deepening understanding of the super-enrichment mechanism and metallogenesis of germanium in deposits.