Synthesis of thermally stable MCM-41 at ambient temperature

A new process to synthesize thermally stable mesoporous molecular sieves of MCM-41 structure based on delayed neutralization at ambient temperature was investigated. All samples synthesized by this new method have BET surface areas of about 1100 m(2)/g and possess high thermal stability up to 900 degrees C. Higher crystallinity and less lattice constriction after calcination were observed for samples with a longer aging period. Those samples with aging time longer than 10 days exhibited four characteristic XRD peaks of MCM-41 both before and after calcination at 560 degrees C. The N-2 adsorption-desorption isotherms of the calcined samples showed larger average pore size and more homogenous pole size distribution. The method was also successfully applied to the synthesis of MCM-41 with different surfactants of hydrocarbon length with 10-18 carbons and proves to be a simple route for obtaining thermally stable MCM-41 at room temperature.