화학공학소재연구정보센터
Applied Catalysis B: Environmental, Vol.163, 50-62, 2015
Preparation of efficient and recoverable organosulfonic acid functionalized alkyl-bridged organosilica nanotubes for esterification and transesterification
A series of arenesulfonic or propylsulfonic acid functionalized ethane- or benzene-bridged organosilica nanotubes hybrid catalysts, Si(Ph/Et)Si-Ar/Pr-SO3H NTs, was demonstrated for the first time by a single step nonionic surfactant-templated sol-gel co-condensation approach. The pore morphologies, textual and acidic properties of as-prepared hybrid catalysts were characterized by TEM observations, nitrogen gas porosimetry measurements and acid-base titration, while the structural integrity of the incorporated organosulfonic acid groups and silica/carbon framework in the hybrid catalysts were studied by C-13 CP-MAS NMR and Si-29 MAS NMR. As the novel solid acid catalysts, the catalytic activity and stability of the Si(Ph/Et)Si-Ar/Pr-SO3H NTs were evaluated by esterification of palmitic acid and transesterification of yellow horn seed oil with methanol under refluxing temperature (65 degrees C) and atmospheric pressure. Based on the physicochemical properties and catalytic testing results, the excellent heterogeneous acid catalytic behaviors of as-prepared tubular hybrid catalysts were revealed in terms of their considerably high Bronsted acid-site density and acid strength, unique textural properties, interesting morphology as well as hydrophobic surface. (C) 2014 Elsevier B.V. All rights reserved.