PURPOSE: To produce zeolite of an MFI type structure having a monoclinic structure by calcining a crystal which is formed by reaction in an aq. medium contg. an SiO2 source, TiO2, fluoride ions and structure control agent at specific ratios at a specific temp.
CONSTITUTION: The reaction mixture is formed in the aq. medium contg. the SiO2, such as hydrogel, TiO2, such as crystalline the fluoride ions, such as HF, and the structure control agent, such as ternary amine, and further, a co-mobility agent, such as oxalic acid at need. The aq. soln. described above is formed to a Ti/Si molar ratio of 1.5 to 0.002, an F/Si molar ratio of 10 to 0.04, an H2O/Si molar ratio of 400 to 4, a structure control agent/Si molar ratio of 2 to 0.02 and pH of 10.5 to 1.5. The reaction mixture is crystallized at about 50 to 240°C. The crystalline precipitate is then recovered and dried and, is then calcined at 450°C and more particularly about 500°C. As a result, the zeolite of the MFI structure which is mainly composed of the SiO2 and TiO2, contains 0.01 to 0.8 wt.% F, has the formula: (Si96-xTix)O192 (X=0.1 to 6) and has the monoclinic structure and the X-ray diffraction diagram of the table is obtd.
JIYANRIYUKU GUUTO
ANRI KESURERU
| JPS5951273A | 1984-03-24 | |||
| JPS60127217A | 1985-07-06 | |||
| JPS6011222A | 1985-01-21 | |||
| JPS5696720A | 1981-08-05 |