![]() By using solid waste as silicon sources, the cost of the aerogel will be reduced significantly. An innovative low cost process was developed to prepare ash-based-aerogel. Moreover, the study also explored the research on making aerogel from fly ash and bottom ash. The paper reported the use of a cellulose-MTES precursor to fabricate hydrophobic aerogel with enhanced physical and thermal insulating properties. This study aims to develop a low cost and high performance aerogel. Furthermore cellulose, the most abundant organic polymer, may prove to be the key to achieving low-cost aerogel. Since aerogel is made up of a network of nano-structured silica chain, its flexibility can be synthetically altered with modification to this network―cross-linking of the silica with organic additives such as cellulose, isocyanate, methyltriethoxysilane (MTES), and methyltrimethoxysilane (MTMS) have been demonstrated to be effective in enhancing the aerogel’s physical properties. ![]() Much research has been focused on improving the flexibility and mechanical strength of aerogel. waste leaves) could be another silica sources with 13% - 48% of silica content. If these wastes could be converted into highly valuable silica aerogels, the environmental pollution problem caused by a stack of fly/bottom ash will be reduced greatly. Fly ash and bottom ash are industrial wastes released by factories and thermal power plants, which consist of high content of silica. In order to reduce the cost of fabrication and realize the commercial production of silica aerogels, green and cheap silica sources are very necessary. The high cost of production lies in expensive silica sources, cumbersome solvent exchange process and high energy cost. High cost of aerogel production on large scale and the fragility of aerogel have limited its practical applications and commercialization. Ĥ) Alkoxysilane aerogels by ambient pressure drying. ģ) Alkoxysilane aerogels by supercritical drying. Herrmann explored this approach.Ģ) Water glass aerogels by ambient pressure drying. Currently, there are at least four routes to produce aerogels via different gel formations and drying processes.ġ) Water glass aerogels by supercritical drying. Shrinkage can be eliminated by either supercritical drying or drying at ambient pressure after modification of gel surface. ![]() During the drying process, shrinkage of the gel caused by capillary force in gel pores will lead to a collapse and thereby a failure of aerogel formation. The process of aerogel includes two steps: formation of lyogel by water glass or alkoxide and drying (replacement of solvent by air). Samuel Kistler produced the first aerogel by water glass, whereas the alkoxides approach is currently more popular because it requires fewer solvent exchanges. Silica aerogel is commonly synthesized by either water glass or alkoxides. As a result of their unique properties, aerogels are being considered for applications as thermal and sound insulation of structural elements in buildings, oil absorbers and catalysts. enhancement of solid waste recycling rate by converting waste to high value-added materials, super thermal and acoustic insulation materials in green building and removal of oil spilled into surface drainage.Īerogels are the world’s lightest solid materials and have the lowest thermal conductivity of solid. The preliminary results showed that the materials have great potential for environmental application, i.e. Preparation of aerogel with solid waste (fly ash/bottom ash) is also discussed. They were hydrophobic in nature and had low thermal conductivity. The fabricated aerogel exhibited high flexibility with a Young’s modulus of compression of 0.33 MPa and the density of 0.132 g/cm3. The physical properties of the resulting aerogels were characterized by thermogravimetry, scanning electron microscopy, nitrogen adsorption-desorption, contact angle, thermal conductivity measurements, compression testing and Fourier transform infrared spectroscopy. This paper presents the synthesis of a highly flexible polymer modified silica aerogel with the use of a cellulose-methyltriethoxysilane (MTES) precursor in a two-step acid-base catalyzed sol-gel process. ![]() Due to their excellent characteristics, such as extremely low thermal conductivity, low density and high porosity, the silica aerogels become promising potential adsorbents, catalysts, thermal insulation, and acoustic absorption materials for environmental purposes. Silica aerogels are light weight, nanostructured, and highly porous materials with an open pore structure. ![]()
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