A new low-cost carbon-silica composite adsorbent from a by-product of the sugar industry

This research aims at producing a new carbon silica composite adsorbent by using molasses, a by-product of the sugar industry as the carbon source. Sodium silicate (Na2SiO3) and potassium silicate (K2SiO3) were used as low-cost sources of silica, in place of the commonly used and more expensive tetraethyl orthosilicate (C8H20O4Si, TEOS). The effect of carbon:silica sources ratios from 0.1 to 5 on the porous structure of composites were investigated. The composites obtained at optimum condition are also characterized by their moisture and ash contents, FTIR, TGA and SEM. The optimum condition for obtaining the highest surface area was a carbon:silica ratio 1.5 for Na2SiO3 and K2SiO3 with a specific surface area of 329 and 269 m2/g, respectively. These surface areas were comparable with the sample using TEOS as the silica source produced under optimum conditions (carbon:silica ratio 0.5, 460 m2/g). The resulting adsorbents from all three silica sources contained significant mesoporosity (57-70%) with an average pore size of 3.61-5.31 nm. Therefore, a low-cost silica source has the potential to produce a mesoporous carbon-silica composite adsorbent. (c) 2020 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the 17th International Conference on Advanced Nano Materials.