Patent ID: 11926587
Assignee: LYONDELL CHEMICAL TECHNOLOGY, L.P.
Field: Chemical engineering (Chemistry)
Classification: CPC B  C | IPC C

Claim 0:
1. A process for converting a C4 Raffinate stream to propylene, the process comprising:
a) providing a C4 Raffinate stream comprising 1-butene and 2-butene to a metathesis reactor, the metathesis reactor containing a metathesis catalyst system, wherein the C4 Raffinate stream is provided as a weight hourly space velocity ranging from 1 to 8.3/h;
b) contacting the C4 Raffinate stream with the metathesis catalyst system under conditions suitable for forming an intermediate product stream comprising propylene, a heavy (C4+) component, and ethylene; and
c) discharging the intermediate product stream to a first separation unit and separating the intermediate product stream into fractions comprising [1] a first product stream having a higher propylene concentration than the intermediate product stream and [2] a second product stream having a lower propylene concentration than the intermediate product stream, wherein the second product stream contains ethylene but in an amount less than 15 wt. %, wherein the second product stream is recycled by combining the second product stream with the C4 Raffinate stream or is recycled by introduction into the metathesis reactor, and, wherein the process for converting the C4 Raffinate stream to propylene is performed in the absence of added ethylene.