A new successful short time synthesis route for the preparation of FSM is developed using the leached natural aluminosilicate saponite, in combination with a low concentration of cetyltrimethylammoniumbromide [C16H33N+(CH3)(3)Br- or CTMA] as surfactant. The leaching of the smectite increases with higher acid concentrations (5-10 M HCI) and temperature (25 degreesC and 100 degreesC). The leached saponite generated by these acid treatments allows the formation of mesoporous aluminosilicate hexagonal structures (FSM-16) with high porosity (max. 0.6 cm(3)/g), high specific surface area (max. 900 m(2)/g), thick pore wall, and uniform pore structure.