Aqueous electrolytes and non-electrolytes under hydrothermal conditions

许多地质和工业过程发生在远远超出常规室温测量范围的条件下。 本提案的目的是发展必要的知识基础和理论理解，以描述发电站、核反应堆、地热矿体、深海热液喷口和重油热采中遇到的水系统在极端温度和压力下的行为。 灵敏的流量量热计和密度计由惰性材料制成，可承受腐蚀性条件，将用于确定温度高达400°C和压力高达350个大气压的液态水中简单电解质和有机分子的热力学性质，以检查离子电荷和有机官能团在接近水临界点的条件下的影响。化学物种的形式，以及它们在高温高压下的平衡常数，将通过紫外可见光谱法在新开发的带有蓝宝石窗口的流动系统中，通过静态和流动池溶解度技术，以及能够达到超临界条件的独一无二的高精度电导装置来确定。 金刚石砧和高压流动池将与共焦拉曼显微镜结合使用，以检查相位关系，并通过在极端温度和压力下直接观察来识别主要化学物质。 一个新的项目将研究在热液喷口遇到的条件下生物前分子的稳定性。这项工作的新奇在于正在研究的非常极端的条件，识别不寻常的影响的潜力，以及需要开发专门的仪器技术，以获得这些非常积极的条件下复杂的水溶液体系的定量数据。

Many geological and industrial processes take place at conditions far beyond the range of conventional room temperature measurements.  The objective of this proposal is to develop the knowledge base and theoretical understanding needed to describe the behaviour of aqueous systems at extremes of temperature and pressure encountered in electrical power stations, nuclear reactors, geothermal ore bodies, deep-ocean hydrothermal vents, and the thermal recovery of heavy oil.   Sensitive flow calorimeters and densitometers, constructed of inert materials to withstand the corrosive conditions, will be used to determine the thermodynamic properties of simple electrolytes and organic molecules in liquid water at temperatures up to 400°C and pressures as high as 350 atmospheres, in order to examine the effects of ionic charge and organic functional groups under conditions approaching the critical point of water. The form of the chemical species, and their equilibrium constants at high temperature and pressure, will be determined by UV-visible spectroscopy in a newly-developed flow system with sapphire windows, by static and flow-cell solubility techniques, and with a one-of-a-kind, high-precision conductance apparatus capable of reaching supercritical conditions.  Diamond anvil and high pressure flow cells will be used in conjunction with confocal Raman microscopy to examine phase relations and to identify major chemical species by direct observation at extremes of temperature and pressure.  A new project will examine the stability of pre-biotic molecules under conditions encountered in  hydrothermal vents. The novelty in the work lies in the very extreme conditions being studied, the potential for identifying unusual effects, and the need to develop specialised instrumental techniques to obtain quantitative data for complex aqueous systems under these very aggressive conditions.