Measurement of the Solubilities of Scheelite and Ferberite in Hydrothermal Solutions With In-Situ pH Measurement

通过原位 pH 测量测量热液中白钨矿和镁铁矿的溶解度

基本信息

批准号：
0087065
负责人：
Scott Wood
金额：
$ 20.51万
依托单位：
Regents of the University of Idaho
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2001
资助国家：
美国
起止时间：
2001-01-01 至 2004-12-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=0087065&HistoricalAwards=false
关键词：
Measurement Solubilities Scheelite Ferberite Hydrothermal

项目摘要

WoodEAR-0087065Tungsten is a metal of strategic importance. Reliable thermodynamic data with which to calculate the solubilities of the most important tungsten ores, scheelite (CaWO4) and ferberite (FeWO4), and the mass transfer of tungsten, in hydrothermal solutions are generally not available. Yet, such data are required to develop comprehensive genetic models of hydrothermal tungsten deposits; these models can guide exploration for new tungsten resources. A study is therefore proposed in which the solubilities of scheelite and ferberite will be measured in non-complexing solutions at saturated water vapor pressure as a function of temperature from 50 degrees to 290 degrees C, pH and ionic strength. The pH will be monitored directly in-situ using a hydrogen electrode concentration cell (HECC) of the type developed and used successfully at Oak Ridge National Laboratory. From the solubilities measured as a function of pH and ionic strength, the solubility products for scheelite and ferberite, and the dissociation constants for tungstic acid (H2WO40), all of which are essential thermodynamic data for the calculation of W mass transfer, can be derived. The project will involve one Ph.D. student who will be trained in hydrothermal geochemistry and high-pressure/high-temperature experimental methods. This project will not only result in the acquisition of high-quality thermodynamic data with which to calculate tungsten mineral solubilities and W mass transfer in hydrothermal solutions, but will also provide the PI with an HECC for future studies of other systems of geochemical interest.

Woodear-0087065Tungsten是一种具有战略重要性的金属。在水热溶液中，使用可靠的热力学数据来计算最重要的钨矿石，Scheelite（Cawo4）和Ferberite（Like4）的溶解度以及钨的质量转移。然而，需要这样的数据来开发水热钨沉积物的综合遗传模型；这些模型可以指导探索新的钨资源。因此，提出了一项研究，其中将在饱和的水蒸气压力下以非复合溶液在50度至290度C，pH和离子强度的温度下测量Scheelite和Ferberite的溶解度。将使用在Oak Ridge国家实验室成功使用并成功使用的氢电极浓度电池（HECC）直接在原位中监测pH。根据pH和离子强度的函数测量的溶解度，Scheelite和Ferberite的溶解性产物以及钨酸的解离常数（H2WO40），所有这些都是用于计算W质量传递的必不可少的热力学数据，可以得出。该项目将涉及一位博士学位。将接受水热地球化学和高压/高温实验方法培训的学生。该项目不仅会导致获得高质量的热力学数据，以计算水热溶液中的钨矿物溶解度和W质量转移，而且还将为PI提供HECC，以供未来对地球化学兴趣系统的未来研究。