| In the process of the development of human society, more and more new materials come to the fore. Aerogel is a new technology product born in the last century, with many excellent properties such as thermal properties, acoustic properties, mechanical properties, optical properties and electrical performance and so on. The features of its three-dimensional porous network structure endowed with the aerogel in adsorption material field of value. Now, it has been listed as one of the Top Ten Science and Technology.International aerogel research focuses on three types, inorganic aerogel, organic aerogel and inorganic-organic composite aerogel. The application involve relatively broad, from civil building material to space laboratory with particle collector. Preparation of aerogel is constantly updated, and the selection of raw materials range is gradually expanding. The research of cellulose as raw material for cellulosic aerogel has just started to develop in recent years, but its prospects attract the vision of scholars of all walks of life. It not only has the features of traditional aerogel, but also added a bodegradable, biocompatibility and other properties. The range of raw materials to prepare the cellulosic aerogel is wide, basically have natural cellulose, regenerated cellulose fiber and cellulose derivatives. Compared with the traditional, cellulosic aerogel has a broader application prospects.This research paper use the cellulose from the laboratory-homemade to prepare the lignocellulosic aerogel (LCA), according to the national standard to extract the cellulose from orchroma lagopus, with alkali solution system for solvent, using Sol-Gel wet gel preparation process and supercritical drying technology to prepare out the LCA. The following is the main content:1That take a different quality of wood cellulose dissolved in cryogenic condition, and then put it in the incubator warming to gel, after that, replaced the water by organic solvent, and dried them by supercritical drying, and compared with other drying methods. Determine the best process and basic parameters of the preparation of LCA.2Make the characterization and performance testing of the LCA. Using conventional methods to observe the macroscopic surface morphology and measure the density; Using atomic force microscope (AFM) and scanning electron microscopy (SEM) for the microscopic and internal morphology analysis to determine its internal morphology is network; The infrared spectra (FT-IR) and X-ray diffraction (XRD) analysis methods are used to analyze the functional groups of the LCA and crystal morphology, to detect its structure changes in the forming process; Using BET analysis method to study the pore diameter distribution; The mechanical properties are determined in mechanics experimental, and we know the best performance is toughness. Thermogravimetric analysis and thermal conductivity determination indicated that LCA can be used as the ideal heat insulation materials, and thermal conductivity of LCA will rise with the increasing of the concentration of cellulose. Determination of the LCA in moisture absorption and desorption properties found that the performance of humidity is much higher than the cellulose itself, we analyzed and believed that this is due to the existing pore is humidity regulation.3Research on adsorption effect of LCA on methylene blue organic molecules. Along with the increase of the initial quality concentration of solution, the decoloring ability of LCA decreased. The best temperature of its adsorption is40℃, higher than that temperature; adsorption decoloring ability can be drop quickly. The decoloring ability is obvious, the color removal rate increases rapidly, but it achieves adsorption equilibrium after two hours. The color removal efficiency rapid changes when pH value of dye solution increases below7. But it changes smoothly when pH value increases in the alkaline range. Because of the porous network of LCA, its adsorption effect is better than cellulose itself. |
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