Thermodynamics of the minerals of the jarosite group

黄钾铁矾土和相关矿物总是存在于酸雨作用或酸性矿山废水酸化的自然环境中。尽管它们很重要，也很常见，但能够描述元素在黄钾铁矾土和水溶液中的溶解度、沉淀量和分布的数据是支离破碎的或值得怀疑的。在这里，我建议用量热法测定黄钾铁矾族矿物的热力学性质(生成热、生成熵和生成吉布斯自由能)。然后，通过数学规划分析，对测得的热力学参数进行黄钾铁矾石矿物的高P-T实验。结果将是一个内部一致的黄钾铁矾族矿物热力学数据集。所获得的系统学将为酸输入影响环境中的溶解、沉淀、污染物迁移和元素分馏模型提供良好的基础。

Jarosite and related minerals are invariably found in natural environments acidified either through the action of acid rain or by acidic mine drainage. In spite of their importance and common occurrence, the data which could describe the solubility, precipitation, and distribution of elements between jarosite and aqueous solutions are fragmented or questionable. Here I propose to determine the thermodynamic properties (formation enthalpy, entropy, and Gibbs free energy of formation) of the jarosite group of minerals by calorimetric techniques. The measured thermodynamic quantities will be then confronted with high P-T experiments on jarosite minerals via a mathematical programming analysis. The result will be an internally consistent thermodynamic data set for jarosite group minerals. The systematics obtained will provide an excellent basis for models of dissolution, precipitation, pollutant transport, and element fractionation in environments affected by acidic input.