Independent temperature and humidity control technology has been demonstrated to reduce energy consumption by 10-30% in a high-temperature and high-humidity environment. Among the available solutions, liquid desiccant air-conditioning (LDAC) systems are recognized for their high energy efficiency. Beyond dehumidification, LDAC systems can also sterilize and purify the air, making them a promising candidate for next-generation air-conditioning applications, particularly in climates where both temperature and humidity control are essential for comfort and indoor air quality. Despite these advantages, the practical adoption of LDAC systems has been constrained by the properties of traditional absorbents. Lithium chloride (LiCl), the most common liquid desiccant, is effective at moisture removal but exhibits strong corrosiveness toward metals. This characteristic increases maintenance requirements, limits material compatibility, and restricts widespread application. Ionic liquids, a new class of absorbents, present a viable alternative to conventional salt-based desiccants. They are non-corrosive to metals, possess high chemical stability, and can be regenerated at low temperatures. These properties reduce system corrosion risks, lower operating costs, and enable greater flexibility in heat source utilization, including the potential use of low-grade waste heat or renewable thermal energy. In this study, a small-scale LDAC system with an air-handling capacity of 3,000 CMH was constructed to evaluate the performance of a newly developed ionic liquid. Experimental results indicated that the ionic liquid achieved dehumidification performance comparable to that of LiCl, while eliminating the issue of metal corrosion. Given these findings, ionic liquids can effectively replace traditional absorbents, thereby facilitating the broader adoption of independent temperature and humidity control technology and enabling substantial energy savings in air-conditioning systems.
Chen et al. (Tue,) studied this question.