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Ambient humidity control has a very important practical significance to human health, agricultural and industrial production, goods storage. Adsorption desiccant wheel dehumidification large, high-efficiency, low dew point dry air continuously, such as environmental protection and energy-saving advantages and is widely used. The core of the system for runner adsorption material, it is the key factor to affect system dehumidification performance, therefore, the research and development of high adsorption performance runner adsorption material, has important theoretical significance and practical value. Calcium chloride and lithium chloride, as modifier, ceramic fiber paper is sequentially impregnated with sodium silicate and zeolite mixture, prepared in the modified salt solution, etc., a high adsorbing performance of the ceramic base modified silica / zeolite composite. Investigate the influence of the concentration of sodium silicate, zeolite, salt concentration, soaking temperature and dipping time on the adsorption properties of the complexes; using scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS), Fourier transform infrared (FTIR), X-ray diffraction (XRD), photoelectron spectroscopy (XPS), the porous medium, analysis of the composition of the composite, surface morphology, pore structure characterization; by thermogravimetric (TG), the temperature-programmed desorption (TPD) Evaluation composites desorption performance, and thermal stability. Experiments With the increase of the concentration of sodium silicate, the amount of ceramic sheets on the hanging plastic zeolite coating amount increases, the adsorption performance increases affect the total amount of the composite adsorbent; the amount of the molecular sieve, but too much will be detached from the substrate ; the impregnated salt concentration affect the doping metal ions in the composite adsorbent; as impregnation temperature rise, the saturation adsorption amount increases, but an excessively high impregnation temperature, the specific surface area decreased significantly, the adsorption performance decline. The SEM figure shows that the complexes can be more evenly dispersed in the surface of the substrate and voids; EDS, XPS analysis showed the existence and content of the modified ion; FTIR and XRD showed that the basic structure of the zeolite before and after the modified unchanged; pore size analysis showed that the zeolite after modification reduces the specific surface area, pore volume and pore size is increased; lower TG showed that the temperature under the maximum thermal weight loss rate of the modified composite; the TPD curves indicate modified composite lower desorption temperature and the desorption activation energy. Dynamic and static adsorption results show that: molecular sieve adsorption performance has improved significantly after modification. In RH 60% 25 ° C under static adsorption, zeolite, lithium-modified, the percentage of the saturated adsorption of the calcium-modified adsorbents were 19.49%, 63.66% and 55.87%. Dynamic adsorption: at 25 ° C, low-humidity (RH 40%), lithium modification, the amount of adsorption in the complex of the calcium-modified 13X molecular sieve were 1.54 times and 1.36 times, while at high humidity (RH 80% ), lithium modified, the amount of adsorption on the calcium-modified complexes were 13X molecular sieves, 3.26 times and 3.32 times, but at RH 30% or less, the adsorption properties of the modified composite is lower than the molecular sieve; as the ambient temperature increases , the amount of adsorption of the modified composite is increased, and when elevated to 55 ° C, the adsorption amount is slightly decreased.
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