Process for preparing ethylene and/or propylene

Abstract

The present invention provides a process for preparing ethylene and / or propylene, wherein oxygenates and olefins are converted to ethylene and / or propylene over a zeolite-comprising catalyst, comprising the steps of: a) reacting in a first reactor an oxygenate feed over the zeolite-comprising catalyst at a temperature in the range of from 350 to 1000 °C and retrieving from the first reactor a first reactor effluent stream comprising gaseous products, including ethylene and / or propylene, and zeolite-comprising catalyst; b) reacting in a second reactor an olefin feed over the zeolite-comprising catalyst at a temperature in the range of from 500 to 700 °C and retrieving from the second reactor a second reactor effluent stream comprising gaseous products, including ethylene and / or propylene, and zeolite-comprising catalyst; c) providing the first and second reactor effluent stream to one or more gas / solid separators to retrieve zeolite-comprising catalyst from the first and second reactor effluent; d) providing part of the zeolite-comprising catalyst retrieved in step (c) to the first reactor; e) regenerating another part of the zeolite-comprising catalyst retrieved in step (c) by contacting the zeolite-comprising catalyst with oxygen at elevated temperatures to provide a hot regenerated zeolite-comprising catalyst; and f) providing part of the hot regenerated zeolite-comprising catalyst to the first reactor and another part of the hot regenerated zeolite-comprising catalyst to the second reactor. The invention further provides a system suitable for preparing ethylene and propylene and the use thereof.

Description

technical field [0001] The present invention relates to a process for the production of ethylene and / or propylene, a reaction system suitable for this process and the use of said reaction system. Background technique [0002] Typically, ethylene and propylene are produced by steam cracking paraffinic feedstocks comprising ethane, propane, naphtha, and wax oils. An alternative route to ethylene and propylene is the oxygenate to olefin (OTO) process. Due to the increasing availability of natural gas, interest in OTO processes for the production of ethylene and propylene is increasing. Methane in natural gas can be converted to, for example, methanol or dimethyl ether (DME), both of which are suitable feedstocks for use as OTO processes. [0003] In an OTO process, an oxygenate such as methanol is supplied to a reaction zone comprising a suitable conversion catalyst and converted to ethylene and propylene. Apart from the desired ethylene and propylene, most of the methanol i...

AI Technical Summary

Problems solved by technology

However, it was suggested in the course of WO2009 / 156433 that catalyst from the XTO zone, i.e. catalyst with high coke on it, be sent directly to the OC zone, which may negatively affect the olefin cracking selectivity

[0012] Another disadvantage of the WO2009 / 156433 process is that the process requires both the XTO zone and the OC zone to have separate gas / solid sections to separate the product from the catalyst

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