Process for making zeolite ZSM-45 with a dimethyldiethylammonium directing agent
AssigneeMobil Oil Corporation
InventorGuenter H. Kuehl
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Abstract
This invention relates to a method for preparing a synthetic porous crystalline aluminosilicate zeolite, characterized as zeolite ZSM-45. This crystalline material may have a silica to alumina molar ratio of at least 8. This synthetic zeolite is analogous, in some respects, to the naturally occurring zeolite, levynite. The ZSM-45 zeolite is prepared with a dimethyldiethylammonium directing agent. ZSM-45 exhibits a characteristic X-ray diffraction pattern.
Claims6
A method for preparing a synthetic porous crystalline aluminosilicate zeolite, said aluminosilicate zeolite having a silica to alumina ratio of at least 8, said aluminosilicate zeolite as calcined further being characterized by an X-ray diffraction pattern exhibiting values substantially as set forth in Table 1 of the specification, said method comprising preparing a mixture capable of forming said aluminosilicate zeolite, said mixture containing sources of alkali metal ions, an oxide of aluminum, an oxide of silicon, a dimethyldiethylammonium ion and water and having a composition in terms of moles of oxides, falling within the following ranges:
- ______________________________________ SiO.sub.2 /Al.sub.2 O.sub.3 10-80 H.sub.2 O/OH.sup.- 15-100 OH.sup.- /SiO.sub.2 0.40-0.80 DMDEA/(DMDEA + Z) 0.75-1.0 ______________________________________
- wherein DMDEA represents said dimethyldiethylammonium ion and Z represents said alkali metal ion, and maintaining said mixture under sufficient conditions until said crystalline aluminosilicate zeolite is formed.
A synthetic porous crystalline aluminosilicate zeolite having a composition, on an anhydrous basis and in terms of moles of oxides per mole of alumina, expressed by the formula:
- (0.8-1.8)R.sub.2 O:(0.0-0.3)Na.sub.2 O:(0.0-0.5)K.sub.2 O:Al.sub.2 O.sub.3 :xSiO.sub.2
- wherein R.sub.2 O is the oxide of dimethyldiethylammonium ions and x is at least 8, said aluminosilicate zeolite as calcined being characterized by an X-ray diffraction pattern exhibiting values substantially as set forth in Table 1 of the specification.
Dependencies are inferred from the claim text.