期刊名称:Eastern-European Journal of Enterprise Technologies
印刷版ISSN:1729-3774
电子版ISSN:1729-4061
出版年度:2018
卷号:1
期号:6
页码:52-58
DOI:10.15587/1729-4061.2018.123896
语种:English
出版社:PC Technology Center
摘要:Heat energy storage is one of the most common technical solutions in the conditions of operation of low-potential and renewable energy sources. Adsorption heat energy storage devices based on the composite media “silica gel – salt” are the most effective in these conditions. The technique and technology of sol-gel synthesis of the composite adsorption materials “silica gel – sodium sulfate” and “silica gel – sodium acetate” have been developed. A special feature of this technique is a two-stage process involving the formation of silicon phase nuclei in the interaction of aqueous solutions of silicate glass and sulphuric or acetic acids in the presence of a polymeric quaternary ammonium salt and subsequent coarsening of the particles with the gradual addition of solutions of silicate glass and the corresponding acids. The essence of the technology consists in successive stages of formation and integration of the silicic phase nuclei, hydrolysis of functional OH- groups, filtration and drying of the fine precipitate. A qualitative difference in the adsorption properties of the synthesized composites and the mechanical mixture of salt – silica gel with sorption capacity inferior to them on average by 30% is revealed by differential thermal analysis. The processes of application of the composite adsorption materials “silica gel – sodium sulfate” and “silica gel – sodium acetate” obtained by the sol-gel method have been studied. A qualitative difference in the kinetics of adsorption of water by the composite adsorbents is shown as compared to massive salts. It is established that the amount of heat of adsorption of water vapor by the composite adsorbents of the materials “silica gel – sodium sulfate” and “silica gel – sodium acetate” is approximately 30 % greater than the linear superposition of salt and silica gel.
关键词:heat-accumulating materials;composite sorbents;sol-gel synthesis;adsorption heat;energy storage density;kinetics of hydration