| 摘要 |
A process for oxygenate conversion using a family of crystalline aluminosilicate zeolites that is a layered pentasil zeolite with a silica or fluorine modified surface. These zeolites are represented by the empirical formula:;Mmn+Rrp+Al1-xExSiyOz ;where M is an alkali, alkaline earth, or rare earth metal such as sodium or potassium, R can be a mixture of organoammonium cations and E is a framework element such as gallium, iron, boron, or indium. These zeolites are characterized by unique x-ray diffraction patterns and compositions and have catalytic properties for carrying out oxygenate conversion processes. |
| 主权项 |
1. A process for the conversion of oxygenates to olefins comprising:
passing an oxygenate feedstream to an oxygenate conversion reactor operated at oxygenate conversion reaction conditions, wherein the reactor includes a catalyst having a layered pentasil structure and wherein the surface of the catalyst has been modified with silica or fluorine, to generate a process stream comprising olefins, wherein the catalyst is a zeolite having a microporous crystalline structure comprising a framework of AlO2 and SiO2 tetrahedral units, and an empirical composition in the as synthesized and anhydrous basis expressed by the empirical formula of:
Mmn+Rrp+AlSiyOz where M is at least one exchangeable cation selected from the group consisting of alkali and alkaline earth metals, “m” is the mole ratio of M to Al and varies from 0 to 3, R is at least one organoammonium cation selected from the group consisting of quaternary ammonium cations, diquaternary ammonium cations, quaternary phosphonium cations, methonium cations, and mixtures thereof, “r” is the mole ratio of R to Al and has a value of about 0.1 to about 30, “n” is the weight average valence of M and has a value of about 1 to about 2, “p” is the weighted average valence of R and has a value of about 1 to about 2, “y” is the mole ratio of Si to Al and varies from greater than 32 to about 200 and “z” is the mole ratio of O to Al and has a value determined by the equation:
z=(m·n+r·p+3+4·y)/2. |
