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Adsorption desalination and cooling is a promising technology that has recently been investigated. In this study, a silica gel powder composite (SGPC) with nano-copper (NC) and polyvinyl pyrrolidone (PVP) was synthesized by mechanical grinding and melt blending for the first time. It can improve the thermal conductivity of silica gel powder (SGP) and the operation efficiency of the adsorption desalination and cooling system (ADCS). By measuring the curve of temperature variation to compare the four thermal conductivity enhancers (TCE), graphite powder (GP), carbon nanotubes (CNT), nano-alumina (NA) and NC, it was found that NC had the best thermal conductivity enhancement. The microstructure, adsorption and thermal properties of the SGPC samples were systematically characterized by scanning electron microscopy (SEM), thermogravimetric analyzer (TGA) and thermal constant analyzer. The results showed that the adsorption capacity of SGPC with NC content of 0–1.6 wt% was in the range of 0.29–0.33 g −1. The thermal conductivity of SGPC with NC content of 0.8wt%, 1.2 wt%, and 1.6 wt% was found to be improved by 114%, 156% and 185% compared to the parent SGP, and the thermal conductivity was effectively enhanced. Thus, the developed adsorbent has eximious water adsorbability and thermal conductivity and has good adsorption/desorption cycle stability, which is attractive for ADCS. [ABSTRACT FROM AUTHOR]

In order to solve undercooling and phase separation of sodium acetate trihydrate (SAT), experimental screening method was used to select nucleating agents and thickeners that are suitable for SAT, and the optimal ratio was identified. Through screening experiments of nucleating agents, it is found that disodium hydrogen phosphate can be used as an effective nucleating agent for SAT. When the weight content of disodium hydrogen phosphate in SAT is 2%, the degree of undercooling was reduced to approximately 2 K. The addition of 1–1.5% (weight) of xanthan gum (XG) to SAT can effectively inhibit the phase separation. Since the properties of SAT changes after the modification, the corresponding comparison analysis was performed. The results showed that XG has a significant influence on the SAT performance of SAT. With the addition of 1.5 wt % of XG in pure SAT, the latent heat of fusion and solid/liquid volume expansion reduce by 5.2% and 5.4% respectively, and the thermal conductivity and solid/liquid density also decreases accordingly. [ABSTRACT FROM AUTHOR]

Calcium ions can react with polyethylene glycol (PEG) to form a form-stable phase change material, but the low thermal conductivity hinders its practical application. In this paper, hydroxylated multi-walled carbon nanotubes (MWCNTs) with different mass are introduced into PEG1500·CaCl2 form-stable phase change material to prepare a new type of energy storage material. Carbon nanotubes increased the mean free path (MFP) of phonons and effectively reduced the interfacial thermal resistance between pure PEG and PEG1500·CaCl2 3D skeleton structure. Thermal conductivity was significant improved after increasing MWCNTs mass, while the latent heat decreases. At 1.5 wt%, composite material shows the highest phase change temperature of 42 °C, and its thermal conductivity is 291.30% higher than pure PEG1500·CaCl2. This article can provide some suggestions for the preparation and application of high thermal conductivity form-stable phase change materials. [ABSTRACT FROM AUTHOR]