Hybrid extruded mixed zeolite catalysts for synthesis of light olefins
A catalyst for converting dimethyl ether into light olefins, including ethylene and propylene. The catalyst comprises a mixture of two zeolites, ZSM-5 and ZSM-35, intimately mixed and kept in close proximity in a porous extruded binder system. The resulting combination of zeolites demonstrates a synergistic effect with respect to the conversion of the dimethyl ether and has improved resistance to deactivation due to carbon and coke formation than the individual zeolites alone when operating in this reaction. The catalyst is used to produce ethylene and propylene from a feed mixture containing methanol, dimethyl ether and water.
1. A composition comprising at least one catalyst particle, wherein each of said at least one catalyst particle(s) contains a ZSM-5 zeolite, a ZSM-35 zeolite, and a binder.
2. The composition of claim 1 wherein said ZSM-5 zeolite is present in an amount of from about 10 wt. % to about 95 wt. % of the total amount of zeolite in said composition.
3. The composition of claim 2 wherein said ZSM-5 zeolite is present in an amount of from about 10 wt. % to about 90 wt. % of the total amount of zeolite in said composition.
4. The composition of claim 3 wherein said ZSM-5 zeolite is present in an amount of from about 40 wt % to about 90 wt. % of the total amount of zeolite in said composition.
5. The composition of claim 4 wherein said ZSM-5 zeolite is present in an amount of from about 55 wt. % to about 85 wt. % of the total amount of zeolite in said composition.
6. The composition of claim 1 wherein said ZSM-35 zeolite is present in an amount of from about 5 wt. % to about 90 wt. % of the total amount of zeolite in said composition.
7. The composition of claim 6 wherein said ZSM-35 zeolite is present in an amount of from about 10 wt. % to about 90 wt. % of the total amount of zeolite in said composition.
8. The composition of claim 7 wherein said ZSM-35 zeolite is present in an amount of from about 10 wt. % to about 60 wt. % of the total amount of zeolite in said composition.
9. The composition of claim 8 wherein said ZSM-35 zeolite is present in an amount of from about 15 wt % to about 45 wt. % of the total amount of zeolite in said composition.
10. The composition of claim 1 wherein said binder is selected from the group consisting of silicas, clays, aluminas, and mixtures thereof.
11. The composition of claim 10 wherein said binder is a silica.
12. The composition of claim 11 wherein said silica is derived from colloidal silica.
13. The composition of claim 11 wherein said silica is an amorphous silica.
14. The composition of claim 10 wherein said binder is a clay.
15. The composition of claim 10 wherein said binder is an alumina.
16. The composition of claim 15 wherein said alumina is an amorphous alumina.