Experimental Study On The Vapor Pressure Over Lithium Chloride Aqueous Solution

Lithium chloride aqueous solution is working fluid widely used in food industry, chemical industry, air conditioning systems etc, owing to its large solubility, strong hydrophilicity and stable performance.The water vapor pressure difference between the solution and ambient air is the essential drive for absorption and regeneration process. In other words, water vapor pressure is very important for the application of lithium chloride aqueous solution. Therefore, this property is widely studied and is considered to be the best studied one. Although there have been published quite large amount of experimental data, they are subject to short ranges either on temperature or concentration. Noticeably, data for subzero temperature is scares.Recently, some researcher proposed using mixture of calcium chloride and lithium chloride or solutions with ionic liquids such as [Dmim]C1or [Dmim]BF4. However, as a basic property the vapor pressure of lithium chloride aqueous solution still worth some investigation. In view of the proposal of using lithium chloride as working fluid in frost-free air source heat pump system and dehumidifier system, which may encounter subzero temperature situations. This thesis conducts experimental investigation on vapor pressure of lithium chloride aqueous solution in the range of5%～50%,-20℃～90℃by static method, aiming to provide some reference to extend the usage of lithium chloride aqueous solution.Experimental system with high accuracy potassium resistance temperature sensor and capacitance diaphragm gauge, plus thermostat has been developed. The measurement of vapor pressure of pure deionized water showed that this system is reliable. Up to date,5%、10%、15%、20%、30%and40%wt solution have been studied, and solutions of other concentrations will be measured next on.