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CA-3048119-C - PROCESS TO CONVERT SYNTHESIS GAS TO OLEFINS USING A BIFUNCTIONAL CHROMIUM / ZINC OXIDE-SAPO-34 CATALYST

CA3048119CCA 3048119 CCA3048119 CCA 3048119CCA-3048119-C

Abstract

A process for preparing C2 to C3 olefins includes introducing a feed stream having a volumetric ratio of hydrogen to carbon monoxide from greater than 0.5: 1 to less than 5: 1 into a reactor, and contacting the feed stream with a bifunctional catalyst. The bifunctional catalyst includes a Cr/Zn oxide methanol synthesis component having a Cr to Zn molar ratio from greater than 1.0: 1 to less than 2.15: 1, and a SAPO-34 silicoaluminophosphate microporous crystalline material. The reactor operates at a temperature ranging from 350 °C to 450 °C, and a pressure ranging from 10 bar (1.0 MPa) to 60 bar (6.0 MPa). The process has a cumulative productivity of C2 to C3 olefins greater than 15 kg C2 to C3 olefins/kg catalyst.

Inventors

  • Davy L.S. Nieskens
  • Aysegul Ciftci Sandikci
  • Peter E. Groenendijk
  • Andrzej Malek

Assignees

  • DOW GLOBAL TECHNOLOGIES LLC

Dates

Publication Date
20260505
Application Date
20171221
Priority Date
20161222

Claims (11)

  1. 85424428 CLAIMS: 1. A process for preparing C2 to C3 olefms, comprising: introducing a feed stream into a reactor, wherein the feed stream comprises hydrogen gas and carbon monoxide gas, such that a volumetric ratio of hydrogen to carbon monoxide ranges from greater than 0.5: 1 to less than 5: 1; and contacting the feed stream with a bifunctional catalyst in the reactor, wherein the bifunctional catalyst comprises: ( 1) Cr/Zn oxide methanol synthesis component having a Cr to Zn molar ratio from greater than 1.0: 1 to less than 2.15: 1, and (2) a SAPO-34 silicoaluminophosphate microporous crystalline material, wherein the reactor operates at reaction conditions comprising: (a) a reactor temperature ranging from 350 °C to 450 °C; and (b) a pressure ranging from 10 bar (1.0 MPa) to 60 bar (6.0 MPa), and wherein the process has a cumulative productivity of C2 to C3 olefins greater than 15 kg C2 to C3 olefins/kg catalyst, and wherein the methanol synthesis component is calcined at a temperature of from 375 °C to 425 °C.
  2. 2. The process for preparing C2 to C3 olefins according to claim 1, wherein the Cr to Zn molar ratio is at least 1.1:1.
  3. 3. The process for preparing C2 to C3 olefins according to any one of claims 1 and 2, wherein the Cr to Zn molar ratio is at least 1.5:1.
  4. 4. The process for preparing C2 to C3 olefins according to any one of claims 1 to 3, wherein the reaction conditions comprises a pressure greater than 30 bar (3.0 MPa). 5. The process for preparing C2 to C3 olefins according to any one of claims 1 to 4, wherein the reaction conditions comprises a pressure greater than 45 bar (4.
  5. 5 MPa).
  6. 6. The process for preparing C2 to C3 olefins according to any one of claims 1 to 5, further comprising as a reaction condition a gas hourly space velocity of from 500 reciprocal hours to 12,000 reciprocal hours.
  7. 7. The process for preparing C2 to C3 olefins according to any one of claims 1 to 6, wherein the volumetric ratio of hydrogen to carbon monoxide in the feed stream is from 0.5:1 to 3:1. Date Re9ue/Date Received 2024-03-15 85424428
  8. 8. The process for preparing C2 to C3 olefins according to any one of claims 1 to 7, wherein a weight ratio of the Cr/Zn oxide methanol synthesis component to the SAP0-34 silicoaluminophosphate microporous crystalline material is from 0.1: 1 to 10: 1.
  9. 9. The process for preparing C2 to C3 olefins according to any one of claims 1 to 8, wherein the cumulative productivity of C2 to C3 olefins is from greater than 15 kg C2 to C3 olefins/kg catalyst to 90 kg C2 to C3 olefins/kg catalyst.
  10. 10. The process for preparing C2 to C3 olefins according to any one of claims 1 to 9, wherein the bifunctional catalyst is reduced before the feed stream is contacted with the bifunctional catalyst.
  11. 11. The process for preparing C2 to C3 olefins according to claim 10, wherein the reaction conditions comprises a pressure greater than 50 bar (5.0 MPa). Date Re9ue/Date Received 2024-03-15

Description

PROCESS To CONVERT SYNTHESIS GAS TO OLEFINS USING A BIFUNCTIONAL CHROMIUM/ ZINC OXIDE - SAPO-34 CATALYST CROSS REFERENCE TO RELATED APPLICATION [0001] TECHNICAL FIELD [0002] The present disclosure relates to the field of producing olefins from a feed stream containing carbon. More particularly, the disclosure relates to producing a product mixture comprising C2 and C3 olefins from a feed stream containing hydrogen and carbon monoxide in the presence of a bifunctional catalyst. BACKGROUND [0003] For a number of industrial applications a desirable starting material is a lower olefin, particularly olefins comprising C2, C3, or a combination thereof that can then be converted to industrially desirable materials, such as for producing plastics, fuels, and various downstream chemicals. A variety of methods of producing these has been developed, including petroleum cracking of paraffins and various synthetic processes. [0004] For example, some industrial processes for converting a synthesis gas (syngas) feed to olefins have been developed; among them is the well-known Fischer-Tropsch (FT) process where a mixture of olefins can be produced along with, primarily, longer chain paraffins. This broad product distribution is unfortunately typical for FT processes, and the selectivity to the desired lower olefins obtained via the syngas conversion is typically relatively limited. In response to this, some variations of the FT process have been developed to increase the selectivity to lower olefins. [0005] Despite extensive research in this area, problems generally encountered have included unacceptable levels of co-products such as methanol, methane, C2 and C3 paraffins, and/or C4+ products, which require expensive separation and recycling in order to effectively utilize the C2 Date Rei;ue/Date Received 2024-03-15 WO 2018/119195 PCT/0S2017/067822 and C3 olefins for their desired purpose(s). Thus, there remains a need in the art for processes that are effective to produce C2 and C3 olefins-and having reduced amounts of methanol, methane, C2+C3 paraffins, and/or C4 and higher products-that still enable desired levels of feed stream conversion. It is also desirable that a variety of feed streams may be used and still result in the same or a very similar product distribution, which reduces requirements for feed stream purity and/or feed stream costs. It is also desirable that any catalyst(s) used has/have desirably long lifetimes under processing conditions. Finally, it is desirable that such process minimizes or does not involve production of an intermediate product stream of, for example, methanol, dimethyl ether (DME) or other oxygenates which would then need to be separately converted to the desired hydrocarbon product, i.e., a C2 and/or C3 olefin product. SUMMARY [0006] According to one embodiment, a process for preparing C2 to C3 olefins, compnses: introducing a feed stream into a reactor, wherein the feed stream comprises hydrogen gas and carbon monoxide gas, such that a volumetric ratio of hydrogen to carbon monoxide ranges from greater than 0.5:1 to less than 5:1; and contacting the feed stream with a bifunctional catalyst in the reactor. The bifunctional catalyst comprises: (1) Cr/Zn oxide methanol synthesis component having a Cr to Zn molar ratio from greater than 1.0:1 to less than 2.15:1, and (2) a SAPO-34 silicoaluminophosphate microporous crystalline material. The reactor operates at the following reaction conditions comprising: (a) a reactor temperature ranging from 350 °C to 450 °C; and (b) a pressure ranging from 10 bar (1.0 MPa) to 60 bar (6.0 MPa). The process has a cumulative productivity of C2 to C3 olefins greater than 15 kg C2 to C3 olefins/kg catalyst. [0007] Additional features and advantages will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments described herein, including the detailed description which follows, the claims, as well as the appended drawings. [0008] It is to be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and character of the claimed subject matter. The accompanying drawings are included to provide a further understanding of the various embodiments, and are incorporated into and constitute a part of this specification. The drawings WO 2018/119195 PCT/0S2017/067822 illustrate the various embodiments described herein, and together with the description serve to explain the principles and operations of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWING [0009] The Figure is a plot of cumulative C2-C3 olefins productivity versus molar ratio of chromium to zinc in the Cr/Zn oxide catalyst of the bifunctional catalyst according to embodiments disclosed and described herein. DETAILED DESCRIP