Authors: J.D. Peña, L.A. Rios
Affilation: Applied Physicochemical Processes Research Group, Colombia
Pages: 145 - 148
Keywords: nanoporous silica, glycerol monostearate, glicerol, tetraethylortosilicate (TEOS)
Silicas are important supports in heterogeneous catalysis because they have very high specific surface areas, large pore volumes and offer the possibility of incorporating a variety of chemical moieties or heteroatoms within their structure or surface, which act as catalytically active species . Besides, silica provides thermal, mechanical and structural stability. Non-ionic templates such as Triton X-100 (C8H17(C6H4)(EO)10H), Brij56 (C16H33(EO)10H) y Pluronic F108 (PEO-PPO-PEO) have been traditionally used for the synthesis of porous silicas [2,3], these templates have critical drawbacks like their high cost and non-renewable nature. Therefore, in this work it was investigated the use of templates that are renewable, cheap and highly available, specifically glycerol (Gly) and glycerol monostearate (ME). These substances are derived from fats and oils, they are not toxic and are environmentally friendly due to their high biodegradability. Tetraethylorthosilicate (TEOS) was employed as the silica precursor while ethanol, isopropanol and a water-ethanol mixture were used as solvents. The conditions for the removal of template, by calcination, were determined by thermal analysis (TGA-DTA). Morphological and textural characteristics were determined by nitrogen physisorption analysis and scanning electron microscopy.