铼离子液体溶液的热力学性质研究

Rhenium study has always been the focus of international scientific research domain, owing to its profound martial significance. As the originator of perrhenate ionic liquids, which are stable to air and water, also containing strong catalysis ability, we will deeply study the thermodynamic properties of perrhenate ionic liquid solution in this project. The thermal capacity of perrhenate ionic liquid solution and nonaqueous solution will be measured by low temperature adiabatic calorimeter, and then the activity coefficient will be determined by improved freezing point decline method. The solution heat of the perrhenate ionic liquids will be measured by constant temperature online solution heat calorimeter at different temperatures. The density and apparent molar volume will be measured by Anton Paar densimeter. All these data will be approximated by Pitzer equation, which can obtain the Pitzer parameters of thermal capacity, activity coefficient, volume and enthalpy. Thermodynamic properties of the solutions will be predicted by these parameters, which can explore the applicability of Pitzer electrolyte solution theory. The solubility of perrhenate ionic liquids in organic solvents will be measured firstly. The vaporization enthalpy will be tested by constant temperature thermal gravity method, which can calculate the solubility parameter, and then the reliability of this method will be verified by the estimated solubility using solubility parameter. The surface tension of perrhenate ionic liquid solution will be measured at different temperatures, and then some thermodynamic properties will be estimated by parachor. This project will not only provide basic data for application of perrhenate ionic liquids, but also develop solution chemistry.

金属铼研究有深刻的军事意义，历来是国际科研领域的热门课题。申请人作为对空气和水都稳定、同时又具有很强催化性能的铼离子液体的首创者，在本项目中将深入研究铼离子液体溶液的热力学性质：以低温绝热量热法测定不同浓度铼离子液体水溶液和非水溶液的热容，以改进的凝固点下降法确定其活度系数；用在线恒温环境溶解热热量计测定不同温度的溶解热；用Anton Paar密度计测定密度和表观摩尔体积；以这些实验数据分别拟合出热容、活度系数、体积和焓的Pitzer参数，进而预测溶液的热力学性质，探索Pitzer电解质溶液理论的普适性。测定有机物质在铼离子液体中溶解度；以恒温热重法测定汽化焓，计算铼离子液体溶解度参数，用溶解度参数估算其溶解性能，判断溶解度参数法的可靠性。测定不同浓度铼离子液体溶液的表面张力，通过等张比容估算其热力学性质。本项目成果不仅能为铼离子液体应用开发提供基础数据，同时也发展了溶液化学。

稀散金属铼是一种带有浓厚军事色彩的元素，其合金应用于制造飞机涡轮发动机的叶片，含铼的催化剂更是被广泛应用于石油化工催化裂化，铂铼重整等重要过程。本项目研究铼离子液体及其溶液的热力学性质，研制了萃取法制备高纯度离子液体的工艺，制备铼离子液体的纯度可达99.5%以上，收率大于97%。以Pitzer电解质溶液理论系统研究了该溶液体系的热力学性质，探索了Pitzer电解质溶液理论的普适性。通过对合成的离子液体密度，表面张力，折光率，电导率等参数的测定，估算其体积性质和表面性质，通过等张比容估算其热力学性质。将上述理论扩展至各类不同的离子液体，验证空隙模型的可靠性，均取得较好效果。通过恒温热重法测定离子液体的汽化焓，根据Verevkin方法,在统计热力学基础上计算离子液体的气态和液态热容差，利用动力学模拟方法, 在Hildebrand理论基础上,并基于汽化焓数据,提出预测离子液体极性的新标度δμ, 预测离子液体对有机溶剂、药物分子和生物大分子的溶解性能。利用低温量热仪测定了离子液体的摩尔热容并且利用4种方法计算了298.15K的摩尔热容值，计算推导得到了摩尔溶解焓，摩尔溶解熵和冰点常数。探索了离子液体在催化选择性氧化以及燃料油深度脱硫等几个领域的应用，其氧化脱硫工艺可改变原有加氢脱硫体系高温高压运行的现行技术，在常温常压下几分钟内即可使油品中的硫含量降低至10ppm以内，达到欧洲五号标准。本项目以实现我国稀散金属铼资源的高附加值利用为长远建设目标，产生了一系列高水平研究论文，专利，及中国有色行业标准等成果。力争解决铼应用中的基础性问题，为我国铼的应用提供坚实的理论支撑，将资源优势转化为技术优势，提升我国铼工业领域的整体水平。