| The adsorption refrigeration system will be applied in house, car, ship, etc., because possessing the merits of being driven directly by solar energy or low grade industrial waste heat, simple structure, no moving parts, no noise and long operating life, as well as employing no chlorofluorocarbons as refrigerating agents. Now, there exists an increasing interest in adsorptive refrigeration at home and abroad due to the dual effect of energy saving and environment protecting. However, from the view of commercial application, the technology of solid adsorption refrigeration is not available to wholesale industrialization standard, for existing problem of low specific cooling power per unit of adsorbent, high processing price, as well as low rate of heat utilizing. In the refrigeration cycles, leading cause lies in poor adsorption performance and low heat transfer of solid adsorbents.In this paper, two crucial problems, developing new advanced adsorbents suitable for adsorption refrigeration and enhancing heat transfer of adsorbents, access to the industrialized adsorptive refrigeration are focused on. A series of advanced composite adsorbents provided with high adsorption capacity, low regenerating temperature and suitable adsorption velocity are developed. Raw material proportions for composite adsorbents are optimized. Adsorption performance and adsorptive refrigeration performance of water or alcohol on proposed composite adsorbents were experimentally researched. "Hybrid adsorbents" were prepared through adding additives with good thermal conductivity to raw material, as well as their heat transfer performance, adsorption performance and adsorption refrigeration performance being measured. Process for making adsorbent-coated substrate was discussed. Influence of concentration of the binder and the pore-clearing agent to adsorptive performance of the substrate was researched. The results show that:1,In this paper, the main adsorptive materials were composited with other materials, as a result, two optimized composite adsorbents, with the name QC-1 and QC-2, were prepared. Adsorption capacity of water on sorbent QC-1 is 58.5%, while alcohol on QC-2 can get 0.724, which is remarkably higher than water on 13X molecular sieve and alcohol on activated carbon respectively (At present, they are commonly recognized as the most preferred adsorbents to adsorptive refrigeration system). 2,Adsorption isotherms of water and alcohol on composite sorbent QC-1 and QC-2 were determined respectively, and fitting for isotherms were carried out with D-A equation, whose error can satisfy requirement of engineering design. Adsorptive velocity of water on composite adsorbent (QC-1, QC-2) is higher than that on silica gel.3,Adsorptive working pairs of water and alcohol with composite sorbents respectively take on higher adsorption refrigeration volume and specific cooling power. QC-1-water and QC-2 pairs which take on higher adsorption refrigeration volume and specific cooling power are two kinds of desirable working pairs, which can be applied to the adsorption refrigeration system driven by solar energy or other low-grade heat source.4,Hybrid adsorbents prepared through adding additives with good thermal conductivity take on better heat transfer performance. Heat transfer performance of hybrid adsorbent added with aluminum power with the content of 13%, is distinctly higher than that of the original composite adsorbent, and adsorption refrigeration capacity per unit of the adsorbents is improved 7.5～17.5%. Heat conductivity of adsorptive bed can be remarkably improved through mixing heat conductive material, such as aluminum power or iron power, with composite adsorbents.5,Adsorbent-coated substrates with high adhesion and large adsorption capacity are developed, which helps to solve the cracking-off problem of said substrates after saturated with water. The preferred contents of the pore-clearing agent (5%～10%) and the binder (20%～30%) are gained experimentally. At the condition of the same regenerating tempe...
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