Abstract

Synthesis and textural properties of nanoporous silica with tunable pore size using economic novel linear alkylbenzene sulphonic acid

Author(s): Mohamed A.Betiha, Essam M.Ezzo, Mohamed F.Menoufy, Maged S.Ghattas, Ahmad A.Al-Sabagh

Large-poremesoporous silica with 3D wormhole framework structures (denoted as MFG) were prepared through S-I+ assembly pathway from teraethylorthosilicate (TEOS) as the silica source and inexpensive commercially available alkylbenzene sulphonic acid (LASH) as structure-directing agent. The structure and basic properties of the obtained materials were well characterized by various approaches. The results showed that textural porosity of the disordered structures was correlated with the concentration of the surfactant in water. The calcined mesostructures exhibited large pore sizes (3-12.7 nm), surface areas (387–525 m2/g) and pore volumes (0.32–1.76 cm3/g), depending on the surfactant concentration. The textural properties of MFG, wormhole mesostructures, are comparable to those of hexagonal SBA-15 derivatives and large pore MCM-48. However, unlike the SBA-15 structure type, wherein the 3D pore network is formed by connecting 1D cylindrical mesopores through micropores, MFG mesophases have wormhole framework structures containing fully interconnected 3D mesopores. Also, unlike large pore MCM-48, that requires cost-intensive tetraethylorthosilicate as a silica source and the use of a cosurfactant as a pore expander under strong acid conditions.