A Sustainable Route for the Preparation of Activated Carbon and Silica from Rice Husk

College of Chemistry, Jilin University, Qianjin Street, 2699, Changchun 130012, China.
Journal of hazardous materials (Impact Factor: 4.53). 02/2011; 186(2-3):1314-9. DOI: 10.1016/j.jhazmat.2010.12.007
Source: PubMed


An environmentally friendly and economically effective process to produce silica and activated carbon form rice husk ask simultaneously has been developed in this study. An extraction yield of silica of 72-98% was obtained and the particle size was 40-50 nm. The microstructures of the as-obtained silica powders were characterized by X-ray diffraction (XRD) and infrared spectra (IR). The surface area, iodine number and capacitance value of activated carbon could achieve 570 m(2)/g, 1708 mg/g, 180 F/g, respectively. In the whole synthetic procedure, the wastewater and the carbon dioxide were collected and reutilized. The recovery rate of sodium carbonate was achieved 92.25%. The process is inexpensive, sustainable, environmentally friendly and suitable for large-scale production.

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    • "Silica (SiO 2 ), consisting of two of the most abundant elements in the earth's lithosphere, is an extremely important inorganic material that has been extensively utilized in a wide range of applications, such as glasses, optical fibers, food additives, electric and thermal insulators , absorbents, pharmaceutical products [1] [2]. The common process to manufacture silica involves reacting minerals, such as quartz sand, with sodium carbonate at above 1000 °C, which demands significant energy input for not only the purification of minerals but also the high temperatures [3]. In contrast, low temperature extraction of amorphous silica from biomass has presented to be an eco-friendly and costeffective alternative to the high energy processing of the inorganics [4]. "
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