Synthesis of Pure Silica Molecular Sieves MCM 48

Pure silica molecular sieves MCM 48 were synthesized by hydrothermal method using mixed natural p octyl polyethylene glycol phenyl ether (OP) and cationic cetyltrimethyl ammonium bromide (CTAB) as structure directing agent and tetraethylorthosicilate (TEOS) as silica source. In this method, nonionic surfactant OP utilizing strong van der waals and hydrogen bonding can greatly reduce the amount of cationic surfactant necessary to synthesize MCM 48, at the same time, due to introduction of the nonionic surfactant into the system MCM 48 molecular sieves with more extensively cross linked framework and therefore higher thermal and hydrothermal stability and higher crystallinity were obtained. Several mesoporous molecular sieves could be prepared by simply adjusting the molar ratios of OP to CTAB within a certain range.