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BR-122026002781-A2 - CHEMICAL COMPLEX FOR OXIDATIVE DEHYDROGENATION OF LOWER ALKANES

BR122026002781A2BR 122026002781 A2BR122026002781 A2BR 122026002781A2BR-122026002781-A2

Abstract

A method for converting one or more alkanes into one or more alkenes that includes feeding a first stream containing one or more alkanes and oxygen to an oxidative dehydrogenation reactor; converting at least a portion of one or more alkanes into one or more alkenes in the oxidative dehydrogenation reactor to provide a second stream exiting the oxidative dehydrogenation reactor containing one or more alkanes, one or more alkenes, and one or more oxygen, carbon monoxide, and acetylene; and feeding the second stream to a second reactor containing a catalyst that includes CuO and ZnO and reacting the second stream to provide a third stream exiting the second reactor containing one or more alkanes, one or more alkenes, and lower or undetectable levels of oxygen and acetylene compared to the second stream.

Inventors

  • Yoonhee KIM
  • Xiaoliang Gao
  • Vasily Simanzhenkov
  • Bolaji Olayiwola
  • Shahin Goodarznia
  • David Gent

Assignees

  • NOVA CHEMICALS (INTERNATIONAL) S.A.

Dates

Publication Date
20260317
Application Date
20201204
Priority Date
20191220

Claims (18)

  1. 1. Chemical complex for oxidative dehydrogenation of lower alkanes, CHARACTERIZED in that the chemical complex comprises in a cooperative arrangement: an oxidative dehydrogenation reactor comprising an oxidative dehydrogenation catalyst and designed to accept, optionally in the presence of a diluent, a feed stream containing oxygen and an alkane, and to produce a product stream comprising the corresponding alkene and unreacted alkane, oxygen, diluent, acetylene, oxygenates, or water, or combinations thereof; a quenching tower for cooling the product stream and for removing water and soluble oxygenates from said product stream; a second reactor containing a catalyst comprising CuO and ZnO to provide a second product stream exiting the second reactor comprising an unreacted alkane, alkene and lower or undetectable levels of oxygen and acetylene compared to the product stream; an amine wash to remove any carbon dioxide from said second product stream; a dryer to remove water from said second product stream; and a distillation tower to remove C2/C2+ hydrocarbons from said second product stream to produce an air stream enriched with C1 hydrocarbons, wherein the components of the chemical complex are connected in series in the defined sequence.
  2. 2. Chemical complex, according to claim 1, CHARACTERIZED in that it further comprises a gas mixer flooded with non-flammable liquid for pre-mixing the oxygen-containing gas, the lower alkane-containing gas and heat removal gases before introduction into the oxidative dehydrogenation reactor.
  3. 3. Chemical complex, according to claim 1, CHARACTERIZED in that the oxidative dehydrogenation reactor comprises a single fixed-bed type reactor.
  4. 4. Chemical complex, according to claim 1, CHARACTERIZED in that the oxidative dehydrogenation reactor comprises a single fluidized bed reactor and/or a moving bed reactor.
  5. 5. Chemical complex, according to claim 1, CHARACTERIZED in that the oxidative dehydrogenation reactor comprises a swaying bed type reactor arrangement.
  6. 6. Chemical complex, according to claim 1, CHARACTERIZED in that the oxidative dehydrogenation reactor comprises at least two oxidative dehydrogenation reactors, each comprising the same or different oxidative dehydrogenation catalyst, connected in series, and wherein the product stream from each oxidative dehydrogenation reactor, except the last oxidative dehydrogenation reactor in the series, is fed into a downstream oxidative dehydrogenation reactor.
  7. 7. Chemical complex, according to claim 1, CHARACTERIZED in that the oxidative dehydrogenation reactor comprises at least two oxidative dehydrogenation reactors connected in parallel, each comprising the same or different oxidative dehydrogenation catalyst.
  8. 8. Chemical complex, according to claim 1, CHARACTERIZED in that the chemical complex further comprises a heat exchanger immediately upstream of said quenching tower.
  9. 9. Chemical complex, according to claim 1, CHARACTERIZED in that the chemical complex further comprises a caustic washing tower immediately downstream of the amine washing.
  10. 10. Chemical complex, according to claim 1, CHARACTERIZED in that the C2/C2+ hydrocarbons leave the distillation tower and are directed to a second distillation tower for the separation of unreacted alkane and the corresponding alkene into an unreacted alkane stream and a corresponding alkene stream.
  11. 11. Chemical complex, according to claim 10, CHARACTERIZED in that the second distillation tower further provides separation of the C2/C2+ hydrocarbon portion of the product stream into an unreacted alkane stream and a corresponding alkene stream.
  12. 12. Chemical complex, according to claim 11, CHARACTERIZED in that the unreacted alkane stream is directed back to the oxidative dehydrogenation reactor as part of the feed stream.
  13. 13. Chemical complex, according to claim 1, CHARACTERIZED in that the oxygenated components comprise acetic acid, ethanol, acrylic acid, acetaldehyde, maleic acid or maleic anhydride, or any combination thereof.
  14. 14. Chemical complex, according to claim 1, CHARACTERIZED in that the feed stream comprises carbon dioxide.
  15. 15. Chemical complex, according to claim 1, CHARACTERIZED in that the oxidative dehydrogenation catalyst is supported on or agglomerated with a ligand comprising AlO(OH) or Nb2O5.
  16. 16. Chemical complex, according to claim 14, CHARACTERIZED in that it further comprises the feed stream and the product stream.
  17. 17. Chemical complex, according to claim 16, CHARACTERIZED in that the oxidative dehydrogenation reactor is configured to convert at least part of the alkane into an alkene in a negative process to carbon dioxide.
  18. 18. Chemical complex, according to claim 17, CHARACTERIZED in that the amount of carbon dioxide in the product stream produced by the oxidative dehydrogenation reactor is in a range of about -5% by volume to about -10% by volume of the amount of carbon dioxide in the feed stream accepted by the oxidative dehydrogenation reactor.

Description

[001] The present disclosure relates generally to the oxidative dehydrogenation (ODH) of lower alkanes into corresponding alkenes. In some embodiments, the present disclosure relates to the control of the output levels of carbon monoxide, oxygen and/or acetylene from an ODH process. [002] Olefins such as ethylene, propylene, and butylene are basic building blocks for a variety of commercially valuable polymers. Since naturally occurring sources of olefins do not exist in commercial quantities, polymer producers rely on methods to convert the more abundant lower alkanes into olefins. The method of choice for commercial-scale producers today is steam cracking, a highly endothermic process in which dilute alkanes in steam are subjected very briefly to a temperature of at least 800 °C. The fuel demand to produce the necessary temperatures and the need for equipment that can withstand this temperature significantly increase the overall cost. In addition, the high temperature promotes the formation of coke that accumulates within the system, resulting in the need for costly periodic reactor shutdowns for maintenance and coke removal. [003] Oxidative dehydrogenation (ODH) is an alternative to steam cracking that is exothermic and produces little or no coke. In ODH, a lower alkane, such as ethane, is mixed with oxygen in the presence of a catalyst to produce the corresponding alkene. [004] Except in operational examples or where otherwise indicated, all numbers or expressions relating to quantities of ingredients, reaction conditions, etc., used in the descriptive report and claims should be understood as modified in all cases by the term "about". Consequently, unless otherwise indicated, the numerical parameters presented in the following descriptive report and appended claims are approximations that may vary depending on the desired properties that the present disclosure seeks to achieve. At least, and not as an attempt to limit the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be interpreted in light of the reported number of significant digits and applying common rounding techniques. [005] Although the numerical ranges and parameters that establish the broad scope of the disclosure are approximations, the numerical values established in the specific examples are reported as accurately as possible. Any numerical values, however, inherently contain certain errors necessarily resulting from the standard deviation found in their respective test measurements. [006] Furthermore, it should be understood that any numerical range cited in this document is intended to include all sub-ranges included therein. For example, a range of "1 to 10" is intended to include all sub-ranges between and including the minimum recited value of 1 and the maximum recited value of 10; that is, with a minimum value equal to or greater than 1 and a maximum value equal to or less than 10. As the numerical ranges disclosed are continuous, they include all values between the minimum and maximum values. Unless expressly stated otherwise, the various numerical ranges specified in this application are approximations. [007] As used in this document, the term "alkane" refers to an acyclic saturated hydrocarbon. In many cases, an alkane consists of hydrogen and carbon atoms arranged in a linear structure in which all carbon-carbon bonds are single bonds. Alkanes have the general chemical formula CnH2n+2. In many embodiments of the disclosure, alkane refers to one or more of ethane, propane, butane, pentane, hexane, octane, decane, and dodecane. In particular embodiments, alkane refers to ethane and propane and, in some embodiments, ethane. [008] As used in this document, the term "alkene" refers to unsaturated hydrocarbons containing at least one carbon-carbon double bond. In many embodiments, alkene refers to alpha olefins. In many embodiments of the disclosure, alkene refers to one or more of ethylene, propylene, 1-butene, butadiene, pentene, pentadiene, hexene, octene, decene, and dodecene. In particular embodiments, alkene refers to ethylene and propylene and, in some embodiments, ethylene. [009] As used in this document, the terms "alpha olefin" or "α-olefin" refer to a family of organic compounds that are alkenes (also known as olefins) with a chemical formula CxH2x, distinguished by having a double bond in the primary position or alpha (α) position. In many embodiments of the disclosure, alpha olefin refers to one or more of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, and 1-dodecene. In particular embodiments, alpha olefins refer to ethylene and propylene and, in some embodiments, ethylene. [010] As used in this document, the term "diluent" refers to a gas that forms a non-explosive mixture with hydrocarbons or oxidation gases. However, in some cases, the diluent may participate in the ODH reaction in the presence of an ODH catalyst. Furthermore, in all cases, the dilu