Use of Phosphorus Modified Molecular Sieves in Conversion of Organics to Olefins

摘要

The present invention relates to a process to make light olefins, in a combined XTO−OCP process, from an oxygen-containing, halogenide-containing or sulphur-containing organic feedstock comprising:contacting said oxygen-containing, halogenide-containing or sulphur-containing organic feedstock in the XTO reactor with a catalyst made of a P-modified zeolite (A) at conditions effective to convert at least a portion of the feedstock to form a XTO reactor effluent comprising light olefins and a heavy hydrocarbon fraction;separating said light olefins from said heavy hydrocarbon fraction;contacting said heavy hydrocarbon fraction in the OCP reactor with a catalyst made of a P-modified zeolite (A) at conditions effective to convert at least a portion of said heavy hydrocarbon fraction to light olefins;wherein said P-modified zeolite (A) is made by a process comprising in that order: selecting a zeolite (advantageously with Si/Al ratio between 4 and 500) among H⁺ or NH₄⁺-form of MFI, MEL, FER, MOR, clinoptilolite;introducing P at conditions effective to introduce advantageously at least 0.05 wt % of P;separation of the solid from the liquid if any;an optional washing step or an optional drying step or an optional drying step followed by a washing step;a calcination step.