1 Girma Gonfa, 1,2 Sintayehu Mekuria Hailegiorgis
Applications of Silica Gel
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| 5. Applications of Silica Gel
Silica gel is one of the most signifcant inorganic materials that have been broadly known for stable and desirable properties with respect to temperature and mechanical in- fuences [12]. Silica gel has been exploited potentially for raw materials to produce silicon carbide and soluble silicates. Both of these materials are used in diferent applications such as ceramics, electronics components, refractory in- dustries, manufacture of glass, rubber tire flling material, chromatographic stationary phase, adhesive, components in the ceramic, detergent, and pharmaceuticals. As we know, the price of mineral silica is quite expensive. Hence, the use of biosilica has become better alternative for silicon chip manufacturing [13]. Hence, it needs an efective production of high value-added biosilica from a low-cost material that can be an alternate way compared with the conventional production method. Some of the major applications of silica gel were presented as follows. 5.1. Applications of Nanosilica. Recently, a signifcant amount of silica has been extensively used in diferent in- dustries. In specifc, nanostructured silica has a potential characteristic that is required for recent applications [150] for biosensors, bioimaging, drug delivery systems [3], drinking water, and wastewater treatment [46], CO 2 capture applications [151, 152], superhydrophobic coatings [153], toothpastes as a cleansing agent, reinforcing agent, anti- caking agent in salts, cosmetics applications [11], uses as (a) (b) (c) Figure 6: SEM examination of samples of biosilica made from tef straw (a) and (b) synthetically [97] and (c) silica gel from rice husk [15]. Si-OH Si-CH Si-O Si-O-Si Si-O Si-O BS500 BS700 BS900 1200 1600 2000 800 3200 2400 3600 2800 400 4000 Wave number (cm -1 ) 0 20 40 60 80 100 Tra nsmi tt an ce (%) (a) 3691.76 3750.83 3395.49 1640.69 1073.02 1077.78 805.76 777.09 611.09 469.13 3000 2000 4000 1000 Wavenumber (cm -1 ) 0 40 80 120 Tra nsmi tt an ce (%) (b) Figure 5: FTIR spectra of samples of biosilica produced synthetically from tef straw (a) [97] and palm kernel shell (b) [145]. Advances in Materials Science and Engineering 15 a catalytic support in acetic acid steam reforming [19], in agricultural and environmental remediation potential ap- plicability [38], and so on. In other, silica gel is commonly applied to absorb excess moisture present in the environ- ment. It is put forefront of refrigerant drying, process in- dustries, insulating glass industry, desiccant powder, and packaging desiccants [106]. Silica gel desiccant in sachets is considered to have a scavenger property for water [105]. Utilizing silica nanoparticles as reinforcement or fller in sophisticated composite materials is one of their most well- known uses. Te capacity to achieve homogeneous fller dispersion, which afects how well silica-polymer nano- composites perform overall, is one of its key features [121]. An essential step in preparing silica-polymer nano- composites is the chemical modifcation of silica surfaces with organofunctional groups. It has been noted that surface changes promote the dispersion of silica nanoparticles inside the polymer matrix while also improving the afnity be- tween the organic and inorganic phases [154]. In the con- crete industry, silica nanoparticles have the potential to solve numerous technical problems relating to concrete materials and signifcantly improve the mechanical characteristics of concrete [155]. Tis nanomaterial also has efective since it has a signifcant pozzolanic activity [156]. Concrete and mortar materials can be benefted from the microstructure- improving efects due to the colloidal silica nanoparticle attachment [157]. 5.2. Chemical Applications of Silica Gel. Typically, trialkox- ysilanes with organo-substituted co-condensation or post- synthesis grafting are used to functionalize silica particles [158]. For instance, one of the most often used metals functionalized onto mesoporous silica nanoparticles for catalytic applications is aluminum. It was utilized to deliver drugs [159]. Titanium oxide and iron oxide are incorporated in produced silica nanoparticles. Te synthesized substance was utilized in catalytic processes [160]. Silver nanoparticles based on silica have recently been created and will be utilized to treat Mycobacterium tuberculosis [161]. Similar to this, copper, silver, and copper hydroxy salt were employed to create the corresponding metallic silica nanoparticles, which displayed positive and encouraging outcomes when used as antibacterial agents [162]. 5.3. Biomedical Application of Silica. A widely acknowledged characteristic currently being researched is the use of tai- lored nanostructures for the targeted administration of medications to patients [38, 163]. Tese nanostructures can serve as transporters and direct substances to particular organs or human tissues. Due to their large surface area and porous structure, mesoporous silica nanoparticles have gained considerable respect in this regard. Recently, these tải về 1.86 Mb. Chia sẻ với bạn bè của bạn:
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