초록 ▼

A process for the production of propylene from an olefinic feedstock containing at least one olefin of C4 or greater, the process comprising contacting the olefinic feedstock with a catalyst of the MFI-type having a silicon/aluminum atomic ratio of at least about 180 to produce an effluent containin

A process for the production of propylene from an olefinic feedstock containing at least one olefin of C4 or greater, the process comprising contacting the olefinic feedstock with a catalyst of the MFI-type having a silicon/aluminum atomic ratio of at least about 180 to produce an effluent containing propylene, the propylene yield on an olefin basis being from 30 to 50k based on the olefinic content of the feedstock.

대표청구항 ▼

1. A process for the production of propylene from an olefinic feedstock containing at least one olefin of C4 or greater comprising:(a) providing a crystalline silicate catalyst having an MFI structure and containing aluminum and silicon in the catalyst framework to provide a silicon/aluminum atomic

1. A process for the production of propylene from an olefinic feedstock containing at least one olefin of C4 or greater comprising:(a) providing a crystalline silicate catalyst having an MFI structure and containing aluminum and silicon in the catalyst framework to provide a silicon/aluminum atomic ratio;(b) subjecting said catalyst to a pretreatment procedure involving heating the catalyst in steam and thereafter de-aluminating the catalyst by treating the catalyst with a complexing agent for aluminum to remove aluminum from the catalyst framework and providing a catalyst of increased silicon/aluminum atomic ratio within the range of 180 to 1000; and(c) contacting the pretreated catalyst with the olefinic feedstock containing at least one olefin of C4 or greater to produce an effluent containing propylene in which the propylene yield on an olefin basis is from 30 to 50% based on the olefinic content of the feedstock.2. A process according to claim 1, wherein at least 95 wt. % of any C3 compounds in the effluent are present as propylene.3. A process according to claim 1, wherein the feedstock contacts the catalyst at an inlet temperature of from 500 to 600° C.4. A process according to claim 1, wherein the feedstock is passed over the catalyst at an LHSV of from 10 to 30h?1.5. A process according to claim 1, wherein the catalyst of the MFI structure is silicalite.6. A process according to claim 1, wherein the catalyst of the MFI structure is ZSM-5.7. A process for the production of propylene from an olefinic feedstock containing at least one olefin of C4 or greater comprising:(a) providing a crystalline silicate catalyst having an MFI structure and containing aluminum and silicon in the catalyst framework to provide a silicon/aluminum atomic ratio;(b) subjecting said catalyst to a pretreatment procedure involving heating the catalyst in steam to reduce tetrahedral aluminum in the catalyst framework and form amorphous alumina in the pores of the catalyst;(c) thereafter de-aluminating the catalyst by treating the catalyst with a complexing agent for aluminum to remove amorphous alumina from the catalyst framework and provide a catalyst of increased silicon/aluminum atomic ratio within the range of 180 to 1000; and(d) contacting the pretreated catalyst with the olefinic feedstock containing at least one olefin of C4 or greater to produce an effluent containing propylene in which the propylene yield on an olefin basis is from 30 to 50 wt. % based on the olefinic content of the feedstock.8. The process of claim 7 wherein said catalyst is silicalite and is heated in steam to a temperature within the range of 425°?870° C.