Abstract: Silica-based mesoporous molecular sieves was synthesized by hydrothermal method and characterized by N2 sorption and TEM.The results showed that the pore size of the prepared material increased with the increase of crystallization temperature under the same condition.It was also found that pore size became larger with the increase of crystallization time and the largest one was 4.54 nm when it was crystallized for three days.The opposite behavior was observed for the average specific surface area.Both the p...