Jeffrey Michael Owen Lewis

Methanol to Olefins Process Using Aluminophosphate Molecular Sieve Catalysts

Publisher Summary Synthesis with organic templates at elevated temperatures and pressures has produced more than twenty small, medium and large pore molecular sieve structures. Some of these structures are analogous to conventional aluminosilicate zeolite structures, but a number have novel molecular structures. These new aluminophosphate molecular sieves have a wide range of catalytic properties, depending on the crystal structure and the type of metallic elements incorporated in the framework. Some of these catalysts have unusually high selectivity in certain reactions when compared to the performance of conventional aluminosilicate zeolites. Catalysts made from medium and large pore silicoaluminophosphates are particularly effective for octane improvement in petroleum refining and for reactions involving aromatics. Various other catalytic transformations have also been identified, such as: condensation reactions, e.g. Aldol; reductive aminations; olefin interconversion; the conversion of synthesis gas and the conversion of methanol to light olefins. Acommercially viable catalyst based on a silicoaluminophosphate catalyst has been developed. Selectivities to ethylene or propylene of over 50wt% have been obtained in a fluidized bed reactor. Selectivities to C 2 -C 4 light olefins of 95% can be obtained. These selectivities were obtained at essentially 100% methanol conversion.