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US-12617742-B2 - Integrated process to produce aldehydes from synthesis gas

US12617742B2US 12617742 B2US12617742 B2US 12617742B2US-12617742-B2

Abstract

A process for preparing aldehydes from synthesis gas includes introducing a first feed stream comprising hydrogen gas and a carbon-containing gas comprising carbon monoxide into a reaction zone of a first reactor, converting the first feed stream into a first product stream comprising C 2 to C 4 hydrocarbons in the reaction zone in the presence of a first catalyst, wherein the first product stream further comprises carbon dioxide, removing water and C 4 and higher hydrocarbons from the first product stream to form a second feed stream, and converting the second feed stream into a second product stream comprising propionaldehyde in the presence of a second catalyst in a second reactor. The propionaldehyde can further be converted to methyl methacrylate via oxidative esterification.

Inventors

  • JOSEPH F. DEWILDE
  • Kirk W. Limbach
  • Reetam Chakrabarti

Assignees

  • ROHM AND HAAS COMPANY

Dates

Publication Date
20260505
Application Date
20211117

Claims (16)

  1. 1 . A process comprising: introducing a first feed stream comprising hydrogen gas and a carbon-containing gas comprising carbon dioxide and carbon monoxide into a reaction zone of a first reactor, wherein a volume ratio of carbon dioxide to carbon monoxide in the feed stream is from 0.25 to 1.5; converting the first feed stream into a first product stream comprising C 2 to C 4 hydrocarbons in the reaction zone in the presence of a first catalyst, wherein the first product stream further comprises carbon dioxide; removing water and C 4 and higher hydrocarbons from the first product stream to form a second feed stream; converting the second feed stream into a second product stream comprising propionaldehyde in the presence of a second catalyst in a second reactor.
  2. 2 . The process of claim 1 , wherein the carbon dioxide from the first product stream exiting the second reactor is recycled to the first feed stream.
  3. 3 . The process of claim 1 , further comprising recycling unreacted hydrogen and carbon monoxide to the first feed stream.
  4. 4 . The process of claim 1 , wherein the second product stream further comprises butyraldehyde.
  5. 5 . The process of claim 1 , wherein the step of removing water and C 4 hydrocarbons from the first product stream further comprises removing C 3 hydrocarbons from the first product stream.
  6. 6 . The process of claim 1 , further comprising removing the propionaldehyde from the second product stream.
  7. 7 . The process of claim 1 , further comprising removing any paraffins from the second product stream.
  8. 8 . The process of claim 1 , further comprising converting the propionaldehyde to methyl methacrylate via oxidative esterification.
  9. 9 . The process of claim 1 , wherein the reaction zone operates at a pressure of at least 20 bar.
  10. 10 . The process of claim 1 wherein the first catalyst comprises a mixed metal oxide catalyst or comprises a hybrid catalyst comprising a mixed metal oxide catalyst and a microporous catalyst component.
  11. 11 . The process of claim 10 , wherein the mixed metal oxide catalyst component comprises ZrO 2 .
  12. 12 . The process of claim 10 , wherein the mixed metal oxide catalyst component comprises ZrO 2 and Ga 2 O 3 .
  13. 13 . The process of claim 10 , wherein the microporous catalyst component is a molecular sieve having 8-MR pore openings.
  14. 14 . The process of claim 10 , wherein the microporous catalyst component is a molecular sieve having a Chabazite (CHA) framework.
  15. 15 . The process of claim 10 , wherein the microporous catalyst component is SAPO-34.
  16. 16 . The process of claim 1 , wherein the C 2 to C 4 hydrocarbons consist essentially of C 2 to C 4 olefins.

Description

BACKGROUND Field The present specification generally relates to processes that efficiently convert various carbon-containing streams to aldehydes via C2 to C4 hydrocarbons. Technical Background For a number of industrial applications, hydrocarbons are used, or are starting materials used, to produce plastics, fuels, and various downstream chemicals. C2 to C4 hydrocarbons are particularly useful in downstream applications, such as, for example, preparing aldehydes and further products, such as methyl methacrylate (MMA). MMA is a high-value chemical intermediate for the production of (meth)acrylic polymers and copolymers. A variety of processes for producing lower hydrocarbons has been developed, including petroleum cracking and various synthetic processes. Synthesis gas, known as syngas, a combination of carbon monoxide and hydrogen gas, represents a flexible intermediate that can be obtained from the gasification of biomass, waste, or conventional fuels. Synthetic processes for converting syngas to lower hydrocarbons, are known. The Fischer-Tropsch process has been used to convert syngas to a mixture of olefins along with longer chain paraffins. The Fischer-Tropsch process produces a broad product distribution and selectivity of lower olefins is typically relatively limited. To increase selectivity to lower olefins, variations of the Fischer-Tropsch process have been developed, such as the process disclosed in WO 2019/089206. However, there are at least two azeotropes that encumber the separation in typical syngas to olefin plants, including ethylene/carbon dioxide and ethane/carbon dioxide. See Nagahama et al., Journal of Chemical Engineering of Japan, 7, 5, 1974, pp. 323-328. Separating the carbon dioxide from the olefins is a costly process. While extractive distillation can help break one or the other of these azeotropes, the presence of both azeotropes encourages the use of a non-distillation separation, such as amine scrubbing, of CO2 in syngas to olefin operations. Some of these processes include co-feeding CO2 to the process to reduce the net CO2 selectivity, determined by the CO2 in the product stream less the total CO2 in the feed stream, which may be negative. However, this approach typically leads to reduced productivity of the desired C2 to C4 hydrocarbons. Other process, such as that disclosed in U.S. Pat. No. 10,513,471, use a special catalyst to minimize formation of CO2 in a two-reactor process that converts syngas to C2 to C5 hydrocarbons. U.S. Pat. No. 10,676,419 discloses a two-stage catalyst process for converting syngas to acetic acid, acrylic acid, and/or propylene. In a first stage, syngas is contacted with a first catalyst to produce a first product stream comprising C2 and C3 olefins and/or C2 and C3 paraffins, and the first product stream is then contacted with oxygen gas a second catalyst to produce acrylic acid and acetic acid. Accordingly, a need exists for processes and systems in which aldehydes and/or methyl methacrylate can be produced from syngas efficiently and with high yield. SUMMARY One aspect of the present invention relates to a process comprising introducing a first feed stream comprising hydrogen gas and a carbon-containing gas comprising carbon monoxide into a reaction zone of a first reactor, converting the first feed stream into a first product stream comprising C2 to C4 hydrocarbons in the reaction zone in the presence of a first catalyst, wherein the first product stream further comprises carbon dioxide, removing water and C4 and higher hydrocarbons from the first product stream to form a second feed stream, and converting the second feed stream into a second product stream comprising propionaldehyde and/or butyraldehyde in the presence of a second catalyst in a second reactor. 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 and the claims. 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. DETAILED DESCRIPTION As used herein, it is noted that “synthesis gas” and “syngas” are utilized herein to represent a mixture comprising primarily hydrogen, carbon monoxide, and very often some carbon dioxide. Reference will now be made in detail to embodiments of processes utilizing syngas to prepare C2 to C4 hydrocarbons and further to aldehydes and/or methyl methacrylate. In general, in syngas to hydrocarbon processes, it is desirable to achieve a high productivity of the desired C2 to C4 hydrocarbons, while simultaneously reducing the net selectivity of CO2. A known method to reduce the net selectivity of CO2 is by co-fee