The geochemistry of nitrate deposits: I. Thermodynamics of Mg(NO3)2–H2O and solubilities in the Na+–Mg2+–NO3––SO42––H2O system
The geochemistry of nitrate deposits: I. Thermodynamics of Mg(NO3)2–H2O and solubilities in the Na+–Mg2+–NO3––SO42––H2O system
复制标题
硝酸盐矿床地球化学：I. 硝酸镁 - 水体系的热力学性质以及在钠离子 - 镁离子 - 硝酸根离子 - 硫酸根离子 - 水体系中的溶解度
DOI：
10.1016/j.chemgeo.2016.04.028
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发表时间：
2016-10
期刊：
影响因子：
3.9
通讯作者：
M. Steiger
中科院分区：
文献类型：
--
作者：
M. Steiger
Na ~+-Mg ~（2+）-NO ~ 3--SO_（4 2）--H_2 O四元相互作用体系是与地球上（如阿塔卡马沙漠）、大气气溶胶、受大气污染的天然石材或建筑石材以及洞穴硝酸盐有关的几种天然卤水类型的重要子系统。我们报告了一个离子相互作用（Pitzer）模型，该模型用于计算该互惠系统中的活度和溶解度。模型参数化是基于二元和三元的实验数据。本文报道了Mg（NO_3）_2-H_2O及Na ~+-Mg ~（2+）-NO_3--H_2O和Mg ~（2+）-NO_3--SO_（42）--H_2O三元体系的新参数。我们还报告的细节模型参数化的NaNO 3-H2O二进制。计算的溶解度图的完整的倒数系统进行了比较，实验数据。在大多数情况下，计算结果在实验不确定度范围内。几个重要的不变点的倒易系统的计算和各种固体的稳定范围进行了详细讨论。结果表明，在近室温下，钠镁矾（Na_3NO_3SO_4·H_2O）和钠镁矾（Na_2Mg（SO_4）_2·4H_2O）在互反体系中都具有较大的稳定场。这与它们在硝酸盐矿床中的普遍存在是一致的。
The Na+–Mg2+–NO3––SO42––H2O quaternary reciprocal system is an important subsystem of several natural brine types associated with nitrate deposits on earth (e.g. in the Atacama Desert), in atmospheric aerosols, in natural stone or building stones subjected to atmospheric pollution and in cave nitrates. We report on an ion interaction (Pitzer) model that is used to calculate activities and solubilities in this reciprocal system. Model parameterization is based on binary and ternary experimental data. New parameters are reported for Mg(NO3)2–H2O and the ternary systems Na+–Mg2 +–NO3––H2O and Mg2 +–NO3––SO42––H2O. We also report on the details of the model parameterization of the NaNO3–H2O binary. Calculated solubility diagrams of the full reciprocal system are compared to experimental data. In most cases the calculations are within the experimental uncertainty. Several important invariant points of the reciprocal system are calculated and the stability ranges of the various solids are discussed in detail. It is shown that both darapskite, Na3NO3SO4·H2O, and bloedite, Na2Mg(SO4)2·4H2O, have large stability fields in the reciprocal system at near ambient temperatures. This is in agreement with their common occurrence in nitrate deposits.