Preparation of porous carbons from sugars and their application for carbon capture

Porous carbon materials derived from sugars have been prepared by a new method using silica aerogel as a template. The silica aerogels were prepared by the reaction of tetramethyl orthosilicate (TMOS) and formic acid in the presence of sugar (D-fructose, D-glucose, or sucrose). Prepared silica aerogels containing sugar were carbonized under inert atmosphere followed by the removal of silicate with KOH solution to obtain the porous carbon materials. Prepared porous carbons with smaller amount of TMOS show higher surface areas (up to 312.2 m²/g) than the carbons prepared sugars themselves without using TMOS (108.7-277.3 m²/g). However, the surface areas of porous carbons decreased dramatically at the weight ratios of TMOS/sugar over 0.25. By increasing the surface areas of porous carbons, CO₂ adsorption capacities of porous carbon materials increased up to 3.73 mmol/g.