Multi-stage reactor system and method for converting oxygenates

Abstract

An exemplary method for converting one or more oxygenates to one or more olefins is disclosed. In one exemplary embodiment, the method can include introducing a first input feed into an adiabatic multi-stage reactor having a first reactor bed and a second reactor bed. The method can also include contacting the first input feed with the first reactor bed to maintain a first temperature of the first reactor bed within a first temperature range and produce a first reaction mixture, and introducing a second input feed into the multi-stage reactor such that the first reaction mixture is mixed with the second input feed to produce a first effluent. The method can also include contacting the first effluent with the second reactor bed to maintain a second temperature of the second reactor bed within a second temperature range and produce a second reaction mixture. An exemplary system is also disclosed.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Application No. 63 / 488,867, filed March 7, 2023, the entire contents of which are expressly incorporated herein by reference.

[0002] A multi-reactor system and process for converting oxygenates (e.g., alcohols or ethers), and more particularly, an adiabatic process for converting oxygenates to olefins, is provided.

[0003] Background technology A multi-reactor system and process for converting oxygenates (e.g., alcohols or ethers), and more particularly, an adiabatic process for converting oxygenates to olefins, is provided.

[0004] Fixed-bed adiabatic reactors are among the least expensive reactors available, but they present challenges for processes that release or absorb significant amounts of heat. Endothermic reactions reduce the process temperature depending on the reaction rate and, if heat is not added, can rapidly cool the process. Exothermic reactions increase the process temperature depending on the reaction rate and, if heat is not removed, the reaction can lose selectivity or proceed uncontrollably. Adding or removing heat in such processes requires expensive heat exchangers, ultimately increasing the net heat demand, increasing the system pressure drop, and increasing the difficulty of controlling the process. For processes with high heat exchange demands, it is common to split the fixed bed, add heating or cooling stages, or use generally more expensive multi-tubular fixed-bed reactors in which the reactor itself functions as a heat exchanger. However, such systems can be inefficient, and their applicability can be significantly limited (e.g., steam methane reforming or partial oxidation of propylene to acrylic acid, among others), and they generally cannot accommodate systems that combine exothermic and endothermic processes.

[0005] Thus, there remains a need for improved, efficient, cost-effective, and more versatile systems and methods that can include and combine endothermic and exothermic reactions.

[0006] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate certain aspects of the subject matter disclosed herein and, together with the description, serve to explain some of the principles associated with the disclosed implementations. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram of an exemplary system for converting oxygenates, wherein the first input material comprises at least ethanol. [Figure 2] FIG. 2 is a schematic diagram of another exemplary system for converting oxygenates, wherein the first input material comprises at least methanol and ethanol.

[0008] Wherever practical, like reference numerals refer to like structures, features, or elements.

[0009] Summary of the Invention In certain embodiments of the present subject matter, challenges associated with the conversion of oxygenates can be addressed by including one or more of the features described herein or equivalent / equivalent approaches, as would be understood by one of skill in the art. Aspects of the present subject matter relate to methods and systems for converting one or more oxygenates to one or more olefins.

[0010] In some embodiments, one or more of the following features may optionally be included in any workable combination.

[0011] An exemplary method for converting one or more oxygenates to one or more olefins is disclosed. In one exemplary embodiment, the method includes introducing a first input feedstock into a first end of an adiabatic multi-stage reactor, the first input feedstock including one or more first oxygenates and one or more first olefins, the multi-stage reactor having at least a first reaction stage and a second reaction stage. The first reaction stage is upstream of the second reaction stage, the first reaction stage having a first reactor bed, and the second reaction stage having a second reactor bed. The method also includes contacting the first input feed with the first reactor bed, thereby maintaining a first temperature of the first reactor bed within a first temperature range of about 300°C to 550°C to produce a first reaction mixture, and introducing a second input feed into the multi-stage reactor downstream of the first reaction stage, such that upon exiting the first reaction stage, the first reaction mixture combines with the second input feed to produce a first effluent having a different composition than the first reaction mixture, the second input feed comprising one or more second oxygenates. The method also includes contacting the first effluent with the second reactor bed, thereby maintaining a second temperature of the second reactor bed within a second temperature range of about 300°C to 550°C to produce a second reaction mixture.

[0012] In some embodiments, the multi-stage reactor can have a third reaction stage, the third reaction stage having a third reactor bed. In this case, the method can further include introducing a third input feed into the multi-stage reactor downstream of the second reaction stage, such that upon exiting the second reaction stage, the second reaction mixture can be mixed with the third input feed to produce a second effluent having a different composition from the second reaction mixture, the third input feed comprising one or more third oxygenates. The method also includes contacting the second effluent with the third reactor bed, thereby maintaining a third temperature of the third reactor bed within a third temperature range of about 300°C to 550°C, and producing a third reaction mixture.

[0013] In some embodiments, no external heat is added to the multi-stage reactor during and between each reaction stage. In some embodiments, no heat is removed from the multi-stage reactor during and between each reaction stage. In some embodiments, no first effluent is removed from the multi-stage reactor. In some embodiments, no second effluent is removed from the multi-stage reactor. In some embodiments, no heat is removed from the first reaction mixture before it is combined with the second input feed. In some embodiments, no heat is removed from the second reaction mixture before it is removed from the multi-stage reactor or before it is subsequently combined with the third input feed. In some embodiments, no heat is removed from the third reaction mixture before it is removed from the multi-stage reactor or before it is subsequently combined with the fourth input feed.

[0014] In some embodiments, the one or more first oxygenates comprise a predominant first oxygenate, and the one or more first olefins comprise a predominant first olefin, where the predominant first oxygenate can be ethanol, and the predominant first olefin can be ethylene. In some embodiments, the molar ratio of ethylene to ethanol in the first feedstock can be about 0.25 to 10. In some embodiments, the molar ratio of ethylene to ethanol in the first feedstock can be about 0.25 to 5. In some embodiments, the first temperature range can be about 350°C to 500°C. In some embodiments, the second temperature range can be about 350°C to 500°C. In some embodiments, the third temperature range can be about 350°C to 500°C.

[0015] In some embodiments, at least one of the first reactor bed or the second reactor bed can be a fixed bed. In some embodiments, the third reactor bed can be a fixed bed. In some embodiments, at least one of the first reactor bed or the second reactor bed can be a fluidized bed. In some embodiments, the third reactor bed can be a fluidized bed. In some embodiments, at least one of the first reactor bed or the second reactor bed can be a moving bed. In some embodiments, the third reactor bed can be a moving bed.

[0016] In some embodiments, one or more first oxygenates and one or more second oxygenates can be the same. In some embodiments, one or more first oxygenates, one or more second oxygenates, and one or more tertiary oxygenates can be the same. In some embodiments, one or more first oxygenates comprise one or more C2+ alcohols. In some embodiments, one or more second oxygenates comprise one or more C2+ alcohols. In some embodiments, one or more tertiary oxygenates comprise one or more C2+ alcohols.

[0017] In some embodiments, the one or more first oxygenates comprise a predominant first oxygenate, and the predominant oxygenate can be ethanol. In some embodiments, the one or more second oxygenates comprise a predominant second oxygenate, and the predominant oxygenate can be ethanol. In some embodiments, the one or more tertiary oxygenates comprise a predominant tertiary oxygenate, and the predominant oxygenate can be ethanol.

[0018] In some embodiments, the method may further include introducing the second reaction mixture into a single-stage reactor, the single-stage reactor comprising one or more catalysts, and contacting the second reaction mixture with the one or more catalysts to produce an output stream comprising one or more product olefins. Prior to introducing the second reaction mixture into the single-stage reactor, the method may include reducing the temperature of the second reaction mixture.

[0019] In some embodiments, the method may further include introducing the output stream into a separation subsystem to produce a first stream and a second stream.

[0020] In some embodiments, the second stream can comprise at least one C3+ olefin. In some embodiments, the method can further include combining the first stream with one or more first oxygenates to produce a first input stock. In some embodiments, the first stream can comprise a predominant olefin, which can be ethylene.

[0021] In some embodiments, the method may further include condensing the output stream into a condensed output stream and introducing the condensed output stream into a separation subsystem to produce a first stream and a second stream. In some embodiments, the method may further include combining the first stream with one or more first oxygenates to produce a first input feed. In some embodiments, the first stream may comprise a predominant olefin, which may be ethylene. In some embodiments, the second stream may comprise at least one C3+ olefin.

[0022] In some embodiments, the method may further include introducing the third reaction mixture into a single-stage reactor, the single-stage reactor comprising one or more catalysts, and contacting the third reaction mixture with the one or more catalysts to produce an output stream comprising one or more product olefins.

[0023] In some embodiments, the method may further include reducing the temperature of the third reaction mixture before introducing the third reaction mixture into the single-stage reactor. In some embodiments, the method may further include introducing the output stream into a separation system to produce a first stream and a second stream. In some embodiments, the method may further include combining the first stream with one or more first oxygenates to produce a first input feedstock. In some embodiments, the first stream may comprise a predominant olefin, and the predominant olefin may be ethylene. In some embodiments, the second stream may comprise at least one C3+ olefin.

[0024] In some embodiments, the method may further include condensing the output stream into a condensed output stream and introducing the condensed reaction mixture into a separation subsystem to produce a first stream and a second stream. In some embodiments, the method may further include combining the first stream with one or more first oxygenates to produce a first input material. In some embodiments, the first stream may comprise a predominant olefin, which may be ethylene. In some embodiments, the second stream may comprise at least one C3+ olefin.

[0025] In some embodiments, the method may further include superheating one or more first oxygenates before introducing the first input stream into the adiabatic multi-stage reactor. In some embodiments, the method may further include superheating one or more second oxygenates before introducing the second input stream into the adiabatic multi-stage reactor. In some embodiments, the method may further include superheating one or more third oxygenates before introducing the third input stream into the adiabatic multi-stage reactor.

[0026] In some embodiments, the multi-stage reactor can be at a gauge pressure of from 0 to about 30 bar. In some embodiments, the multi-stage reactor can be at a weight hourly space velocity (WHSV) of from about 0.25 to 15.

[0027] In some embodiments, at least one of the first reactor bed or the second reactor bed can comprise a mixture of catalysts. In some embodiments, the mixture of catalysts can comprise a zeolite and an alcohol dehydration catalyst. In some embodiments, the third reactor bed can comprise a mixture of catalysts. In some embodiments, the mixture of catalysts in the third reactor bed can comprise a zeolite and an alcohol dehydration catalyst.

[0028] In some embodiments, the second feedstock may be introduced into the adiabatic multi-stage reactor at a temperature that may be greater than the temperature of the first reaction mixture. In some embodiments, the third feedstock may be introduced into the adiabatic multi-stage reactor at a temperature that may be greater than the temperature of the second reaction mixture.

[0029] In some embodiments, the multi-stage reactor can include one or more additional reaction stages downstream of the third reaction stage, each having a corresponding reactor bed. In this case, the method can further include introducing a next feedstock into the multi-stage reactor downstream of the previous reaction stage, such that upon exiting the previous reaction stage, the previous reaction mixture can be mixed with the next feedstock to produce an additional effluent having a different composition from the previous reaction mixture, the next feedstock comprising one or more additional oxygenates. The method can also include contacting the previous effluent with a respective reactor bed of one of the one or more additional reaction stages, thereby maintaining the temperature of the respective reactor bed within a temperature range of about 300°C to 550°C, to produce the additional reaction mixture downstream of the previous reaction stage.

[0030] In some embodiments, the one or more first oxygenates can include ethanol and methanol, hi some embodiments, the one or more first olefins can include ethylene, propylene, butene, or any combination thereof.

[0031] In some embodiments, the one or more first oxygenates are methanol-free. In some embodiments, the one or more second oxygenates are methanol-free. In some embodiments, the one or more third oxygenates are methanol-free.

[0032] In another aspect, another method for converting one or more oxygenates to one or more olefins is provided. In some aspects, the method includes introducing a first input feed into a first end of an adiabatic multi-stage reactor, the first input feed comprising one or more first oxygenates, the one or more first oxygenates comprising ethanol and at least one of methanol or dimethyl ether, the multi-stage reactor having at least a first reaction stage and a second reaction stage, the first reaction stage being upstream of the second reaction stage, the first reaction stage comprising a first reactor bed, and the second reaction stage comprising a second reactor bed. The method also includes contacting the first input feed with the first reactor bed, thereby maintaining a first temperature of the first reactor bed within a first temperature range of about 300°C to 550°C to produce a first reaction mixture, and introducing a second input feed into the multi-stage reactor downstream of the first reaction stage, such that upon exiting the first reaction stage, the first reaction mixture combines with the second input feed to produce a first effluent having a different composition than the first reaction mixture, the second input feed comprising one or more second oxygenates. The method further includes contacting the first effluent with the second reactor bed, thereby maintaining a second temperature of the second reactor bed within a second temperature range of about 300°C to 550°C to produce a second reaction mixture.

[0033] In some embodiments, the multi-stage reactor can have a third reaction stage having a third reactor bed, and the method can further include introducing a third input feedstock into the multi-stage reactor downstream of the second reaction stage, such that upon exiting the second reaction stage, the second reaction mixture can be mixed with the third input feedstock to produce a second effluent having a different composition from the second reaction mixture, the third input feedstock comprising one or more third oxygenates. The method can also include contacting the second effluent with the third reactor bed, thereby maintaining a third temperature of the third reactor bed within a third temperature range of about 300°C to 550°C, and producing a third reaction mixture. In some embodiments, the one or more first oxygenates can include ethanol and methanol. In some embodiments, the one or more first oxygenates can include ethanol or dimethyl ether. In such embodiments, the one or more first oxygenates can further include methanol.

[0034] In some embodiments, the one or more second oxygenates can comprise ethanol, methanol, or a combination thereof, hi some embodiments, the one or more second oxygenates do not comprise methanol.

[0035] In some embodiments, the one or more third oxygenates can comprise ethanol, methanol, or a combination thereof, hi some embodiments, the one or more third oxygenates do not comprise methanol.

[0036] In another aspect, a system configured to convert one or more oxygenates to one or more olefins using the above-described method is provided. In some aspects, the system can include the above-described adiabatic multi-stage reactor.

[0037] In another aspect, a method for converting one or more oxygenates to one or more olefins can include introducing a first input feed into a first end of an adiabatic multi-stage reactor assembly, the first input feed can include one or more first oxygenates and at least one or more first olefins and methanol, the multi-stage reactor assembly having at least a first reaction stage and a second reaction stage, the first reaction stage can include the first input feed upstream of the second reaction stage, the first reaction stage having a first reactor bed and the second reaction stage having a second reactor bed. The method also includes contacting the first input feed with the first reactor bed, thereby maintaining a first temperature of the first reactor bed within a first temperature range of about 300°C to 550°C to produce a first reaction mixture, and introducing a second input feed into the multi-stage reactor assembly downstream of the first reaction stage, such that upon exiting the first reaction stage, the first reaction mixture is mixed with the second input feed to produce a first effluent having a different composition from the first reaction mixture. The second input feed comprises one or more second oxygenates. The method also includes contacting the first effluent with the second reactor bed, thereby maintaining a second temperature of the second reactor bed within a second temperature range of about 300°C to 550°C to produce a second reaction mixture.

[0038] In some embodiments, the multi-stage reactor assembly can include a third reaction stage, the third reaction stage including a third reactor bed. In such embodiments, the method can include introducing a third input feedstock into the multi-stage reactor assembly downstream of the second reaction stage, such that upon exiting the second reaction stage, the second reaction mixture can be mixed with the third input feedstock to produce a second effluent, which can have a different composition from the second reaction mixture. The third input feedstock can include one or more third oxygenates. The method can also include contacting the second effluent with the third reactor bed, thereby maintaining a third temperature of the third reactor bed within a third temperature range of about 300°C to 550°C, to produce a third reaction mixture.

[0039] In some embodiments, the multi-stage reactor assembly can include two or more reactors, and the first and second stages can be carried out in a first reactor, and the third stage can be carried out in a second reactor.

[0040] In some embodiments, the multi-stage reactor assembly can include two or more reactors, and the first reactor bed can be disposed within the first reactor, the second reactor bed can be disposed within the second reactor, and in such embodiments, the third reactor bed can be disposed within the third reactor.

[0041] In some embodiments, the first input material can include one or more first oxygenates, one or more first olefins, and methanol.

[0042] In some embodiments, the first input material can include one or more first oxygenates and methanol.

[0043] In some embodiments, the first input material can include one or more first oxygenates and one or more first olefins.

[0044] In some embodiments, the one or more second oxygenates are free of methanol.

[0045] In some embodiments, the one or more third oxygenates do not include methanol.

[0046] In some embodiments, the one or more first olefins can comprise one or more recycled olefins, and the one or more recycled olefins can comprise ethylene, propylene, butene, pentene, or any combination thereof.

[0047] MODE FOR CARRYING OUT THE INVENTION Certain exemplary embodiments will now be described to provide a general understanding of the principles of the structure, function, manufacture, and use of the systems and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those skilled in the art will understand that the systems and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments, and that the scope of the invention is not defined solely by the claims. Features shown or described in connection with one exemplary embodiment may be combined with features of other embodiments. Such modifications and variations are intended to be within the scope of the present invention.

[0048] Dehydration of alcohols to olefins (e.g., ethanol to ethylene) is particularly difficult to achieve in a cost-effective manner. This is a significant issue because, as an example, the production of ethylene from ethanol is the first step in many of the productions of available quantities of renewable chemicals (e.g., bio-based polyethylene or bio-based ethylene glycol), as well as the first step in several commercial processes for producing renewable hydrocarbon fuels from ethanol, particularly sustainable aviation fuel (SAF). Because the dehydration reaction is highly endothermic, achieving high conversions generally requires multiple reaction stages, very high recycle levels, or low feedstock concentrations. All conventional approaches result in very high capital costs and energy usage.

[0049] In the systems and methods described herein, one or more oxygenates (e.g., C1+ alcohols, dimethyl ether, or mixtures thereof), and optionally an olefin co-feed, are converted to a mixture of olefins. The conversion process involves a combination of endothermic dehydration of alcohols or ethers to olefins, followed by net exothermic oligomerization and cracking of the resulting lower carbon number olefins to higher carbon number olefins. To maximize the potential for heat integration between these reactions and minimize capital costs and overall process heat demand, the systems and methods are designed to balance the heat released or absorbed from the overall process by controlling the relative proportions of these two reactions through the staged addition of one or more oxygenates while the overall process is running.

[0050] In the present disclosure, the adiabatic multi-stage reactor is designed to balance the endothermic oxygenate dehydration and exothermic olefin oligomerization reactions by splitting the oxygenate feed into multiple stages within the adiabatic reactor to use the endothermic oxygenate dehydration reaction to offset the heat generated by the exothermic olefin oligomerization process and maintain the internal reactor temperature within desired limits throughout the reactor bed. Thus, the conversion process operates with a more uniform temperature profile throughout the adiabatic multi-stage reactor compared to conventional conversion processes involving only a single oxygenate charge. Furthermore, this heat offset eliminates the need for intermediate removal of material from the reactor during use, significant recycle of unconverted or partially converted oxygenates, or excessive dilution of the oxygenate feedstock, which would be necessary if the oxygenate feed were run as a single charge. It should be noted that the reactor contents can be cooled or heated without removing or adding heat by providing a secondary feedstock at a lower or higher temperature than the reactor contents at that stage.

[0051] Generally, the system disclosed herein for converting one or more oxygenates to one or more olefins includes an adiabatic multi-stage reactor having multiple inputs (e.g., at least first and second input feeds), at least a first reaction stage and a second reaction stage, the first reaction stage being upstream of the second reaction stage. The first reaction stage includes a first reactor bed, and the second reaction stage includes a second reactor bed. During use, the first input feed can be fed into a first end (e.g., inlet) of the adiabatic multi-stage reactor and then contacted with the first reactor bed to produce a first reaction mixture. A second input feed can be introduced into the adiabatic multi-stage reactor downstream of the first reaction stage, and then mixed with the first reaction mixture to produce a first effluent having a different composition from the first reaction mixture. The first effluent can then be contacted with the second reactor bed to produce a second reaction mixture. This second reaction mixture can then pass through the outlet of the reactor or otherwise proceed to the next reaction stage of the reactor (eg, the third reaction stage).

[0052] In some embodiments, no external heat is added to the adiabatic multi-stage reactor during and between each reaction stage. The phrase "external heat" refers to heat supplied to the adiabatic multi-stage reactor that is not otherwise generated by chemical reactions within the adiabatic multi-stage reactor or provided by any of the input raw materials (e.g., the first, second, or third input raw materials). Alternatively or additionally, no heat is removed from the adiabatic multi-stage reactor during and between each reaction stage.

[0053] In some embodiments, a first effluent is not removed from the adiabatic multi-stage reactor. The first effluent can include water, oxygenates, and by-products. Alternatively or additionally, in some embodiments, a second effluent is not removed from the adiabatic multi-stage reactor. The second effluent can include water, oxygenates, olefins, and by-products (e.g., paraffins and aromatics).

[0054] In some embodiments, heat is not removed from the first reaction mixture before it is combined with the second feedstock. Alternatively or additionally, in some embodiments, heat is not removed from the second reaction mixture before it is removed from the adiabatic multi-stage reactor or before it is subsequently combined with the third feedstock.

[0055] The first input feedstock comprises one or more first oxygenates. In the present disclosure, an "oxygenate" is a hydrocarbon containing oxygen as part of its chemical structure. Non-limiting examples of first oxygenates include methanol, ethanol, butanol, pentanol, one or more esters, and / or one or more ethers. In some embodiments, the one or more first oxygenates do not comprise methanol. In some embodiments, the one or more first oxygenates can comprise the same oxygenate, while in other embodiments, the one or more first oxygenates can comprise a mixture of different oxygenates. For example, in some embodiments, the one or more first oxygenates can comprise a predominant first oxygenate, such as ethanol. In such embodiments, the one or more first oxygenates can also comprise one or more other oxygenates, such as methanol, propanol, one or more esters, and / or one or more ethers. As used herein, a "primary first oxygenate" can be present in one or more first oxygenates at a higher weight percent than any other individual oxygenate, e.g., at least 25%, at least 50%, or at least 75% by weight of the one or more first oxygenates. In some embodiments, the primary first oxygenate can be present in an amount of 25% to 99% by weight of the one or more first oxygenates, in an amount of 25% to 90% by weight of the one or more first oxygenates, in an amount of 50% to 99% by weight of the one or more first oxygenates, or in an amount of 75% to 99% by weight of the one or more first oxygenates. It is further contemplated that the primary first oxygenate can be present between any of these recited ranges.

[0056] In some embodiments, the one or more first oxygenates can include ethanol and methanol. Alternatively or additionally, the one or more first oxygenates can include dimethyl ether. Further, the molar ratio of methanol to ethanol in the first feedstock can be about 0.5 to 6, or the molar ratio can be about 1 to 5, or the molar ratio can be about 2 to 5, or the molar ratio can be about 3 to 6, or the molar ratio can be about 3 to 5.

[0057] The one or more first oxygenates can be introduced into the adiabatic multi-stage reactor at a variety of temperatures. For example, in some embodiments, the temperature of the one or more first oxygenates can be about 300°C to 550°C or about 400°C to 500°C. In one embodiment, the temperature of the one or more first oxygenates can be about 300°C to 480°C. In another embodiment, the temperature of the one or more first oxygenates can be about 480°C to 550°C or about 450°C to 500°C. It is contemplated that the temperature of the one or more first oxygenates will not fall outside any of these recited ranges. It is further contemplated that the temperature of the one or more first oxygenates can be between any of these recited ranges.

[0058] The first input material may also include other materials, such as, for example, one or more first olefins. Non-limiting examples of first olefins include ethylene, propylene, butene, and the like. In some embodiments, the one or more first olefins may include the same olefin, while in other embodiments, the one or more first olefins may include a mixture of different olefins. By way of example, in some embodiments, the one or more first olefins may include a predominant first olefin, such as ethylene. As used herein, a "predominant first olefin" may be present in the one or more first olefins at a higher weight percent than any other individual olefin, for example, in an amount of at least 25%, at least 50%, or at least 75% by weight of the one or more first olefins. In some embodiments, the predominant first olefin can be present in an amount of 25% to 99% by weight of the one or more first olefins, in an amount of 25% to 90% by weight of the one or more first olefins, in an amount of 50% to 99% by weight of the one or more first olefins, or in an amount of 75% to 99% by weight of the one or more first olefins. It is further contemplated that the predominant first olefin can be present between any of these recited ranges. In some embodiments, the first feedstock can comprise ethanol and ethylene. For example, the molar ratio of ethylene to ethanol in the first feedstock can be about 0.25 to 10, or the molar ratio of ethylene to ethanol in the first feedstock can be about 0.25 to 5.

[0059] In some embodiments, at least one of the one or more first olefins is provided by recycling olefins within the adiabatic multi-stage system. Such olefins are referred to herein as "recycle olefins." Non-limiting examples of suitable recycled olefins include ethylene, propylene, butene, pentene, or any combination thereof. By way of example, in some embodiments, at least one of the one or more first olefins can include ethylene, alone or in combination with other olefins, e.g., one or more C3+ olefins, by recycling ethylene produced within the adiabatic multi-stage reactor and combining it with one or more first oxygenates (e.g., ethanol) to form the first feedstock. In some embodiments, at least one of the one or more first olefins can include a mixture of recycled C2-C4 olefins, while in other embodiments, at least one of the one or more first olefins can include a C2-C5 olefin.

[0060] The first feedstock can be introduced into the adiabatic multi-stage reactor at a variety of temperatures. For example, in some embodiments, the temperature of the first feedstock can be about 300°C to 550°C or about 400°C to 500°C. It is contemplated that the temperature of the first feedstock will not fall outside any of these recited ranges. It is further contemplated that the temperature of the first feedstock can be between any of these recited ranges.

[0061] During use, the composition of the first feedstock is designed to maintain a first temperature in the first reactor bed within a first temperature range. In some embodiments, the first temperature range can be about 300°C to 550°C. In some embodiments, the first temperature range can be about 300°C to 500°C, about 350°C to 500°C, about 300°C to 400°C, about 350°C to 450°C, about 400°C to 460°C, about 400°C to 480°C, or about 370°C to 480°C. It is contemplated that the first temperature will not fall outside any of these recited ranges. It is further contemplated that the first temperature can be between any of these recited ranges.

[0062] In addition to the composition of the first feedstock, the temperature of the first reactor bed can also depend at least in part on the composition of the first reactor bed. The first reactor bed can include one or more first catalysts. Thus, in some embodiments, the first reactor bed can include one catalyst, while in other embodiments, the first reactor bed includes a mixture of two or more catalysts. Note that the first reactor bed should be designed to overconvert the one or more first oxygenates and one or more olefins (e.g., low-carbon olefins) present in the first feedstock, thereby avoiding overcooling or overheating the first reaction stage, respectively. Thus, the composition of the first reactor bed can be designed based on the desired ratio and composition of the one or more first olefins relative to the total flow rate of the one or more first oxygenates.

[0063] In some embodiments, the one or more first catalysts comprise a doped or undoped zeolite catalyst. Non-limiting examples of suitable zeolite catalysts include molecular sieves of the pentasil type, e.g., ZSM-5 (with MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, having a Si / Al ratio greater than 10, or dealuminated crystalline silicates of the group ZSM-5 (with MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, having a Si / Al ratio greater than 10, or phosphorus- and / or boron-modified crystalline silicates of the group ZSM-5 (with MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, having a Si / Al ratio greater than 10, or silicoaluminophosphate type of the group AEL. Non-limiting examples of suitable dopants for the zeolite catalyst include phosphorus and / or boron. In some embodiments, the zeolite catalyst can be a boron and phosphorus doped zeolite. Additional additives for mixing with the doped zeolite include a SiO2 support doped with a metal dopant, which may include sodium (Na), potassium (K), lithium (Li), beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium, radium, iron (Fe), cobalt (Co), nickel (Ni), lanthanum (La), chromium (Cr), zirconium (Zr), ruthenium (Ru), molybdenum (Mo), iridium (Ir), tungsten (W), copper (Cu), manganese (Mn), vanadium (V), zinc (Zn), titanium (Ti), rhodium (Rh), rhenium (Re), gallium (Ga), palladium (Pd), silver (Ag), indium (In), or any combination thereof.

[0064] In further embodiments, the one or more first catalysts can also include alcohol or ether dehydration specific catalysts, e.g., solid acids, doped or undoped aluminas such as zirconized alumina, gamma alumina, high-purity gamma alumina, or doped gamma alumina, or doped or undoped zeolites with limited olefin oligomerization activity (e.g., when such zeolites selectively dehydrate alcohols to their corresponding olefins in at least 80 mole % under the applied conditions), e.g., H-MFI type zeolites with high Si / Al ratios (e.g., greater than 190) or dealuminated; under certain conditions, Si / Al ratios, H-FER, H-BEA, or HY type zeolites can also be considered monofunctional dehydration catalysts.

[0065] Exemplary catalyst combinations physically mixed in the first reactor bed include a portion (e.g., a first catalyst of the one or more first catalysts) of a doped zeolite, such as a crystalline silicate of the group ZSM-5 (MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT, or TON, with a Si / Al greater than 10, or a crystalline silicate of the group ZSM-5 (MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT, or TON, with a Si / Al greater than 10. The molecular sieve may comprise a dealuminated crystalline silicate of FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, or a phosphorus and / or boron modified crystalline silicate of group ZSM-5 (MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, with Si / Al greater than 10, or a silicoaluminophosphate type molecular sieve of group AEL. An additional additive for mixing with the doped zeolite can be a SiO2 support doped with a metal dopant, including iron (Fe), strontium (Sr), cobalt (Co), nickel (Ni), lanthanum (La), chromium (Cr), zirconium (Zr), ruthenium (Ru), molybdenum (Mo), iridium (Ir), magnesium (Mg), tungsten (W), copper (Cu), manganese (Mn), vanadium (V), zinc (Zn), titanium (Ti), rhodium (Rh), rhenium (Re), gallium (Ga), palladium (Pd), silver (Ag), indium (In), or any combination thereof. The second portion of the catalyst mixture (e.g., the second catalyst of the one or more first catalysts) can include an alcohol or ether dehydration-specific catalyst, as described above.

[0066] The first reactor bed can have a variety of structural configurations. For example, in some embodiments, the first reactor bed is a fixed reactor bed. In some embodiments, the fixed bed reactor is an axial flow fixed bed reactor. In some embodiments, the fixed bed reactor is a radial flow fixed bed reactor. In other embodiments, the first reactor bed is a fluidized bed. In still other embodiments, the first reactor bed is a moving bed.

[0067] The second input feedstock comprises one or more second oxygenates, so named because they are the second oxygenates introduced into the second stage or reactor bed within the reactor. Non-limiting examples of second oxygenates include methanol, ethanol, butanol, pentanol, one or more esters, and / or one or more ethers. In some embodiments, the one or more second oxygenates do not comprise methanol. In some embodiments, the one or more second oxygenates can comprise the same oxygenate, while in other embodiments, the one or more second oxygenates can comprise a mixture of different oxygenates. For example, in some embodiments, the one or more second oxygenates can comprise the second primary oxygenate, such as ethanol. As used herein, a "primary secondary oxygenate" can be present in one or more secondary oxygenates in a higher weight percent than any other individual oxygenate, e.g., at least 25%, at least 50%, or at least 75% by weight of the one or more secondary oxygenates. In some embodiments, the primary secondary oxygenate can be present in an amount of 25% to 99% by weight of the one or more secondary oxygenates, in an amount of 25% to 90% by weight of the one or more secondary oxygenates, in an amount of 50% to 99% by weight of the one or more secondary oxygenates, or in an amount of 75% to 99% by weight of the one or more secondary oxygenates. It is further contemplated that the primary secondary oxygenate can be present between any of these recited ranges.

[0068] Generally, the one or more second oxygenates are the same as the one or more first oxygenates, such that the overall conversion process in the adiabatic multi-stage reactor includes two or more injections of oxygenates, more specifically, separate injections of oxygenates at different reaction stages. This allows the system to control the temperature of the reactor bed, thereby maximizing heat integration throughout the adiabatic multi-stage reactor. In some embodiments, the primary second oxygenate of the one or more second oxygenates can include ethanol. In such embodiments, the one or more second oxygenates can also include one or more other oxygenates, such as methanol, propanol, butanol, pentanol, one or more esters, and / or one or more ethers.

[0069] The one or more second oxygenates can be introduced into the adiabatic multi-stage reactor at a variety of temperatures. For example, in some embodiments, the temperature of the one or more second oxygenates can be about 300°C to 550°C or about 400°C to 500°C. In one embodiment, the temperature of the one or more second oxygenates can be about 300°C to 480°C. In another embodiment, the temperature of the one or more second oxygenates can be about 480°C to 550°C or about 450°C to 500°C. It is contemplated that the temperature of the one or more second oxygenates will not fall outside any of these recited ranges. It is further contemplated that the temperature of the one or more second oxygenates can be between any of these recited ranges.

[0070] The second feedstock can be introduced into the adiabatic multi-stage reactor at a variety of temperatures. For example, in some embodiments, the temperature of the second feedstock can be about 200°C to 550°C, about 200°C to 500°C, about 300°C to 500°C, about 360°C to 400°C, about 400°C to 500°C, or about 450°C to 550°C. It is also contemplated that the temperature of one or more second feedstocks will not fall outside any of these recited ranges. It is further contemplated that the temperature of the second feedstock can be between any of these recited ranges. In some embodiments, the second feedstock is introduced into the adiabatic multi-stage reactor at a temperature that can be higher than the temperature of the first reaction mixture.

[0071] During use, the composition of the second feedstock is designed to maintain a second temperature of the second reactor bed within a second temperature range. In some embodiments, the second temperature range can be about 300°C to 550°C. In some embodiments, the second temperature range can be about 300°C to 500°C, about 350°C to 500°C, about 300°C to 400°C, about 350°C to 450°C, about 400°C to 480°C, or about 380°C to 450°C. It is also contemplated that the second temperature will not fall outside any of these recited ranges. It is further contemplated that the second temperature can be between any of these recited ranges.

[0072] In addition to the composition of the second input feedstock, the temperature of the second reactor bed can also depend at least on the composition of the bifunctional catalyst or particular mixture of catalysts in the second reactor bed. The second reactor bed can contain one or more second catalysts. Thus, in some embodiments, the second reactor bed can contain one catalyst, while in other embodiments, the second reactor bed contains a mixture of two or more monofunctional or bifunctional catalysts. Note that the second reactor bed should be designed to overconvert the one or more second oxygenates and one or more second olefins (e.g., low-carbon olefins) present in the first reaction mixture, thereby avoiding overcooling or overheating the second reaction stage, respectively. Therefore, the composition of the second reactor bed can be designed based on the desired ratio and composition of the one or more second olefins relative to the total flow rate of the one or more second oxygenates.

[0073] In some embodiments, the one or more second catalysts comprise a doped or undoped zeolite catalyst. Non-limiting examples of suitable zeolite catalysts include molecular sieves of the pentasil type, e.g., ZSM-5 (with MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, having a Si / Al ratio greater than 10, or dealuminated crystalline silicates of the group ZSM-5 (with MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, having a Si / Al ratio greater than 10, or phosphorus- and / or boron-modified crystalline silicates of the group ZSM-5 (with MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, having a Si / Al ratio greater than 10, or silicoaluminophosphate type of the group AEL. Non-limiting examples of suitable dopants for zeolite catalysts include phosphorus and / or boron. Additional additives for mixing with doped zeolites include SiO2 supports doped with metal dopants, which may include sodium (Na), potassium (K), lithium (Li), beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium, radium, iron (Fe), cobalt (Co), nickel (Ni), lanthanum (La), chromium (Cr), zirconium (Zr), ruthenium (Ru), molybdenum (Mo), iridium (Ir), tungsten (W), copper (Cu), manganese (Mn), vanadium (V), zinc (Zn), titanium (Ti), rhodium (Rh), rhenium (Re), gallium (Ga), palladium (Pd), silver (Ag), and / or indium (In).

[0074] In further embodiments, the one or more second catalysts can also include alcohol or ether dehydration specific catalysts, e.g., solid acids, doped or undoped aluminas such as zirconized alumina, gamma alumina, high-purity gamma alumina, or doped gamma alumina, or doped or undoped zeolites with limited olefin oligomerization activity (e.g., when such zeolites selectively dehydrate alcohols to their corresponding olefins in at least 80 mole % under the applied conditions), e.g., H-MFI type zeolites with high Si / Al ratios (e.g., greater than 190) or dealuminated; under certain conditions, Si / Al ratios, H-FER, H-BEA, or HY type zeolites can also be considered monofunctional dehydration catalysts.

[0075] Exemplary catalyst combinations physically mixed in the second reactor bed include a portion (e.g., a first catalyst of the one or more second catalysts) doped with a zeolite, such as a crystalline silicate of the group ZSM-5 (MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT, or TON, with a Si / Al greater than 10, or a crystalline silicate of the group ZSM-5 (MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT, or TON, with a Si / Al greater than 10. The molecular sieve may comprise a dealuminated crystalline silicate of FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, or a phosphorus and / or boron modified crystalline silicate of group ZSM-5 (MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, with Si / Al greater than 10, or a silicoaluminophosphate type molecular sieve of group AEL. An additional additive for mixing with the doped zeolite can be a SiO2 support doped with a metal dopant, including iron (Fe), strontium (Sr), cobalt (Co), nickel (Ni), lanthanum (La), chromium (Cr), zirconium (Zr), ruthenium (Ru), molybdenum (Mo), iridium (Ir), magnesium (Mg), tungsten (W), copper (Cu), manganese (Mn), vanadium (V), zinc (Zn), titanium (Ti), rhodium (Rh), rhenium (Re), gallium (Ga), palladium (Pd), silver (Ag), and / or indium (In). The second portion of the catalyst mixture (e.g., a second catalyst of the one or more first catalysts) can include a specific catalyst for alcohol or ether dehydration, as described above.

[0076] The second reactor bed can have a variety of structural configurations. For example, in some embodiments, the second reactor bed is a fixed reactor bed. In some embodiments, the fixed bed reactor is an axial flow fixed bed reactor. In some embodiments, the fixed bed reactor is a radial flow fixed bed reactor. In other embodiments, the second reactor bed is a fluidized bed. In still other embodiments, the second reactor bed is a moving bed.

[0077] In some embodiments, the adiabatic multi-stage reactor can include one or more additional reaction stages, each with a corresponding reactor bed. For example, the adiabatic multi-stage reactor can include a third reaction stage having a third reactor bed. The third reactor bed can have a variety of configurations. For example, in some embodiments, the third reactor bed is a fixed reactor bed. In some embodiments, the fixed bed reactor is an axial flow fixed bed reactor. In some embodiments, the fixed bed reactor is a radial flow fixed bed reactor. In other embodiments, the third reactor bed is a fluidized bed. In still other embodiments, the third reactor bed is a moving bed.

[0078] In use, a third input feed is introduced into the adiabatic multi-stage reactor downstream of the second reaction stage such that upon exiting the second reaction stage, the second reaction mixture can be mixed with the third input feed to produce a second effluent having a different composition from the second reaction mixture. The second effluent then contacts the third reactor bed, thereby maintaining a third temperature of the third reactor bed within a third temperature range of about 300°C to 550°C and producing a third reaction mixture. In some embodiments, heat is not removed from the third reaction mixture before it is removed from the adiabatic multi-stage reactor or before it is subsequently mixed with the fourth input feed.

[0079] The third input material comprises one or more third oxygenates, so named because the one or more third oxygenates are the third oxygenates introduced into the third stage or reactor bed within the reactor. Non-limiting examples of third oxygenates include methanol, ethanol, propanol, butanol, pentanol, one or more esters, and / or one or more ethers. In some embodiments, the one or more third oxygenates do not comprise methanol. In some embodiments, the one or more third oxygenates can comprise the same oxygenate, while in other embodiments, the one or more third oxygenates can comprise a mixture of different oxygenates. For example, in some embodiments, the one or more third oxygenates can comprise a predominant third oxygenate, such as ethanol. As used herein, a "primary tertiary oxygenate" can be present in one or more tertiary oxygenates at a higher weight percent than any other individual oxygenate, e.g., at least 25%, at least 50%, or at least 75% by weight of the one or more tertiary oxygenates. In some embodiments, the primary tertiary oxygenate can be present in an amount of 25% to 99% by weight of the one or more tertiary oxygenates, in an amount of 25% to 90% by weight of the one or more tertiary oxygenates, in an amount of 50% to 99% by weight of the one or more tertiary oxygenates, or in an amount of 75% to 99% by weight of the one or more tertiary oxygenates. It is further contemplated that the primary tertiary oxygenate can be present between any of these recited ranges.

[0080] Generally, the one or more third oxygenates are the same as the one or more first oxygenates and the one or more second oxygenates, such that the overall conversion process in the adiabatic multi-stage reactor includes two or more injections of oxygenates, more specifically, separate injections of oxygenates at different reaction stages. This further enables the system to control the temperature of the reactor bed, thereby maximizing heat integration throughout the adiabatic multi-stage reactor. In some embodiments, the primary third oxygenate of the one or more third oxygenates can include ethanol. In such embodiments, the one or more third oxygenates can also include one or more other oxygenates, such as methanol, propanol, one or more esters, and / or one or more ethers.

[0081] The one or more third oxygenates can be introduced into the adiabatic multi-stage reactor at a variety of temperatures. For example, in some embodiments, the temperature of the one or more third oxygenates can be about 300°C to 550°C or about 400°C to 500°C. In one embodiment, the temperature of the one or more third oxygenates can be about 300°C to 480°C. In another embodiment, the temperature of the one or more third oxygenates can be about 480°C to 550°C or about 450°C to 500°C. It is contemplated that the temperature of the one or more third oxygenates will not fall outside any of these recited ranges. It is further contemplated that the temperature of the one or more third oxygenates can be between any of these recited ranges.

[0082] The third feedstock can be introduced into the adiabatic multi-stage reactor at a variety of temperatures. For example, in some embodiments, the temperature of the third feedstock can be about 200° C. to 550° C., about 200° C. to 500° C., or about 300° C. to 500° C. In some embodiments, the third feedstock is introduced into the adiabatic multi-stage reactor at a temperature that can be higher than the temperature of the second reaction mixture.

[0083] In use, the composition of the third input feedstock is designed to maintain a third temperature of the third reactor bed within a third temperature range. In some embodiments, the third temperature range can be about 300°C to 550°C. In some embodiments, the third temperature range can be about 300°C to 500°C, about 350°C to 500°C, about 300°C to 400°C, about 350°C to 450°C, about 400°C to 460°C, about 400°C to 480°C, or about 370°C to 480°C. It is also contemplated that the third temperature will not fall outside any of these recited ranges. It is further contemplated that the second temperature can be between any of these recited ranges.

[0084] In addition to the composition of the third input feedstock, the temperature of the third reactor bed can also depend at least in part on the composition of the third reactor bed. The third reactor bed can include one or more third catalysts (e.g., bifunctional catalysts). Thus, in some embodiments, the third reactor bed can include one catalyst, while in other embodiments, the third reactor bed includes a mixture of two or more catalysts. Note that the third reactor bed should be designed to overconvert the one or more third oxygenates and one or more third olefins (e.g., low-carbon olefins) present in the second reaction mixture, thereby avoiding overcooling or overheating the third reaction stage, respectively. Thus, the composition of the third reactor bed can be designed based on the desired ratio and composition of the one or more third olefins relative to the total flow rate of the one or more third oxygenates.

[0085] In some embodiments, the one or more third catalysts comprise a doped or undoped zeolite catalyst. Non-limiting examples of suitable zeolite catalysts include molecular sieves of the pentasil type, e.g., ZSM-5 (with MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, having a Si / Al ratio greater than 10, or dealuminated crystalline silicates of the group ZSM-5 (with MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, having a Si / Al ratio greater than 10, or phosphorus- and / or boron-modified crystalline silicates of the group ZSM-5 (with MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, having a Si / Al ratio greater than 10, or silicoaluminophosphate type of the group AEL. Non-limiting examples of suitable dopants for the zeolite catalyst include phosphorus and / or boron. In some embodiments, the zeolite catalyst can be a boron and phosphorus doped zeolite. Additional additives for mixing with doped zeolites include SiO2 supports doped with metal dopants, which may include sodium (Na), potassium (K), lithium (Li), beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium, radium, iron (Fe), cobalt (Co), nickel (Ni), lanthanum (La), chromium (Cr), zirconium (Zr), ruthenium (Ru), molybdenum (Mo), iridium (Ir), tungsten (W), copper (Cu), manganese (Mn), vanadium (V), zinc (Zn), titanium (Ti), rhodium (Rh), rhenium (Re), gallium (Ga), palladium (Pd), silver (Ag), and / or indium (In).

[0086] In further embodiments, the one or more third catalysts can also include alcohol or ether dehydration specific catalysts, e.g., solid acids, doped or undoped aluminas such as zirconized alumina, gamma alumina, high-purity gamma alumina, or doped gamma alumina, or doped or undoped zeolites with limited olefin oligomerization activity (e.g., when such zeolites selectively dehydrate alcohols to their corresponding olefins in at least 80 mole % under the applied conditions), e.g., H-MFI type zeolites with high Si / Al ratios (e.g., greater than 190) or dealuminated; under certain conditions, Si / Al ratios, H-FER, H-BEA, or HY type zeolites can also be considered monofunctional dehydration catalysts.

[0087] Exemplary catalyst combinations physically mixed in the third reactor bed include a portion (e.g., a first catalyst of the one or more third catalysts) doped with a crystalline silicate of the group ZSM-5 (MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT, or TON, with a Si / Al greater than 10, or a crystalline silicate of the group ZSM-5 (MFI or BEA framework), CHA, , FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON dealuminated crystalline silicates, or phosphorus and / or boron modified crystalline silicates of group ZSM-5 (MFI or BEA framework), CHA, FER, FAU, MWW, MOR, EUO, MFS, ZSM-48, MTT or TON, with Si / Al greater than 10, or silicoaluminophosphate type molecular sieves of group AEL. An additional additive for mixing with the doped zeolite can be a SiO2 support doped with a metal dopant, including iron (Fe), strontium (Sr), cobalt (Co), nickel (Ni), lanthanum (La), chromium (Cr), zirconium (Zr), ruthenium (Ru), molybdenum (Mo), iridium (Ir), magnesium (Mg), tungsten (W), copper (Cu), manganese (Mn), vanadium (V), zinc (Zn), titanium (Ti), rhodium (Rh), rhenium (Re), gallium (Ga), palladium (Pd), silver (Ag), and / or indium (In). The second portion of the catalyst mixture (e.g., a second catalyst of the one or more first catalysts) can include a specific catalyst for alcohol or ether dehydration, as described above.

[0088] As described above, an adiabatic multi-stage reactor can include any number of reaction stages, two or more, to achieve a desired output composition. Accordingly, in a further embodiment, the multi-stage reactor includes one or more additional reaction stages downstream of the third reaction stage. Each of the one or more additional reaction stages has a corresponding reactor bed. During use, a subsequent feedstock is introduced into the multi-stage reactor downstream of a previous reaction stage (e.g., the first, second, and third reaction stages) so that, upon exiting the previous reaction stage (e.g., the third reaction stage), the previous reaction mixture (e.g., the third reaction mixture) is mixed with the subsequent feedstock to produce an additional effluent having a different composition from the previous reaction mixture. The subsequent feedstock may include one or more additional oxygenates. The previous effluent then contacts a respective reactor bed of one of the one or more additional reaction stages, thereby maintaining the temperature of the respective reactor bed within a temperature range (e.g., about 300°C to 550°C) and producing an additional reaction mixture downstream of the previous reaction stage.

[0089] While the foregoing description of the adiabatic multi-stage reactor includes all beds within a single adiabatic multi-stage reactor, it is also contemplated herein that each reactor bed may be arranged with a separate adiabatic reactor. For example, in some embodiments, the first, second, and third reactor beds described above are each arranged within a corresponding adiabatic reactor. Such an approach allows for the use of moving beds and, among other things, allows for individual access to each bed for maintenance or replacement. It is further contemplated herein that two or more adiabatic reactors may be implemented, with at least one of the two or more adiabatic reactors containing two or more catalyst beds. For example, in some embodiments, the first adiabatic reactor includes the first and second reactor beds, and the second adiabatic reactor includes the third and, optionally, fourth reactor beds.

[0090] When there are two or more adiabatic reactors, the reactors may be collectively referred to herein as a reactor assembly (e.g., two or more adiabatic multi-stage reactors may be collectively referred to herein as an adiabatic multi-stage reactor assembly). In some embodiments, a method for converting one or more oxygenates to one or more olefins may include introducing a first input feed to a first end of an adiabatic multi-stage reactor assembly, the multi-stage reactor assembly having at least a first reaction stage and a second reaction stage, the first reaction stage being upstream of the second reaction stage, the first reaction stage having a first reactor bed, and the second reaction stage having a second reactor bed. The first input feed may include one or more first oxygenates and at least one of one or more first olefins or methanol. The method may also include contacting the first input feed with a first reactor bed, thereby maintaining a first temperature of the first reactor bed within a first temperature range of about 300°C to 550°C and producing a first reaction mixture, and introducing a second input feed into the multi-stage reactor assembly downstream of the first reaction stage, such that upon exiting the first reaction stage, the first reaction mixture is mixed with the second input feed to produce a first effluent having a different composition from the first reaction mixture. The second input feed may include one or more second oxygenates. The method may also further include contacting the first effluent with a second reactor bed, thereby maintaining a second temperature of the second reactor bed within a second temperature range of about 300°C to 550°C and producing a second reaction mixture.

[0091] In some embodiments, the multi-stage reactor assembly can include a third reaction stage, the third reaction stage having a third reactor bed. In such embodiments, the method can further include introducing a third input feedstock into the multi-stage reactor system downstream of the second reaction stage, such that upon exiting the second reaction stage, the second reaction mixture is mixed with the third input feedstock to produce a second effluent having a different composition from the second reaction mixture. The third input feedstock can include one or more third oxygenates. The method can also include contacting the second effluent with the third reactor bed, thereby maintaining a third temperature of the third reactor bed within a third temperature range of about 300°C to 550°C, and producing a third reaction mixture.

[0092] In some embodiments, the multi-stage reactor assembly can include two or more reactors, and the first and second stages can be carried out in a first reactor, and the third stage can be carried out in a second reactor.

[0093] In some embodiments, the multi-stage reactor assembly can include two or more reactors, and the first reactor bed can be disposed within the first reactor, the second reactor bed can be disposed within the second reactor, and in such embodiments, the third reactor bed can be disposed within the third reactor.

[0094] In embodiments where the adiabatic multi-stage reactor contains only two reactor beds, the output of the adiabatic multi-stage reactor is a second reaction mixture. The composition of the second reaction mixture can include oxygenates, such as alcohols and / or ethers, olefins, such as C5+ olefins, water, and by-products, such as saturates. In some embodiments, the alcohols include ethanol, propanol, butanol, etc.

[0095] In embodiments where the adiabatic multi-stage reactor comprises three reactor beds, the output of the adiabatic multi-stage reactor is a third reaction mixture. The composition of the third reaction mixture can include oxygenates, e.g., alcohols and / or ethers, olefins, e.g., C5+ olefins, water, and by-products, e.g., saturates. In some embodiments, the alcohols include ethanol, propanol, butanol, etc.

[0096] The present system for converting oxygenates can include additional elements. For example, the present system can include, in addition to the adiabatic multi-stage reactor, one or more of the following: a single-stage reactor, one or more heat exchanger units, a condenser, a separation subsystem (e.g., a distillation system), one or more furnaces, or any combination thereof. It should be noted that additional elements present in the system, not described in detail herein, are also contemplated herein.

[0097] In some embodiments, the system can include a single-stage reactor comprising a reactor bed having one or more catalysts. During use, the output of the adiabatic multi-stage reactor (e.g., the second reaction mixture or the third reaction mixture) can be introduced into the single-stage reactor and contacted with one or more catalysts to produce an output stream comprising one or more product olefins. The one or more product olefins can comprise C2 to C7 olefins, e.g., ethylene, propylene, butene, pentene, etc., or any combination thereof. In one embodiment, the one or more product olefins can comprise at least ethylene.

[0098] In embodiments where the adiabatic multi-stage reactor contains only two reactor beds, the temperature of the second reaction mixture can be reduced before the second reaction mixture is introduced into the single-stage reactor. In embodiments where the adiabatic multi-stage reactor contains only three reactor beds, the temperature of the third reaction mixture can be reduced before the third reaction mixture is introduced into the single-stage reactor. In either case, this temperature reduction can be accomplished, for example, by a heat exchanger unit.

[0099] In some embodiments, the output stream can be introduced into a separation subsystem to produce a first stream and a second stream. In certain embodiments, the output stream can be condensed into a condensed output stream before introducing the output stream into the separation subsystem, and the condensed output stream can be introduced into the separation subsystem. The separation subsystem can include various separation units, such as a distillation system, a liquid-liquid separation system, a liquid extraction system, a membrane separation system, and an adsorbent system, for performing a separation process to produce the first and second streams.

[0100] The first stream can comprise ethylene, propylene, butane, or any combination thereof. In one embodiment, the first stream can comprise a predominant olefin, such as ethylene. As used herein, a "predominant olefin" can be present in the first stream at a higher weight percent than any other individual olefin, for example, at least 50 weight percent, at least 75 weight percent, or at least 95 weight percent of the olefins in the first stream. In some embodiments, the primary olefin may be present in an amount of 25% to 99% by weight of the olefin in the first stream, 25% to 90% by weight of the olefin in the first stream, 35% to 90% by weight of the olefin in the first stream, 40% to 90% by weight of the olefin in the first stream, 45% to 90% by weight of the olefin in the first stream, 50% to 99% by weight of the olefin in the first stream, 55% to 99% by weight of the olefin in the first stream, 60% to 99% by weight of the olefin in the first stream, or 75% to 99% by weight of the olefin in the first stream. In some embodiments, the primary olefin may be present in an amount of 35% to 65% by weight of the olefin in the first stream. It is further contemplated that the primary olefin may be present between any of these recited ranges.

[0101] The second stream can include at least one C3+ olefin, such as a C3-C7 olefin. Additionally, in some embodiments, the second stream can include by-products, such as aromatics and saturates.

[0102] In embodiments where olefin recycle is incorporated into the system, the first stream can be combined with one or more first oxygenates to produce a first input feedstock. In some embodiments, the one or more first oxygenates can be heated, for example, to a temperature of about 200°C to 500°C, about 200°C to 500°C, about 375°C to 500°C, about 360°C to 550°C, or about 400°C to 500°C, before introducing the first input stream into the adiabatic multi-stage reactor. Alternatively or additionally, the one or more second oxygenates can be heated, for example, to a temperature of about 200°C to 500°C, about 200°C to 500°C, about 375°C to 500°C, about 360°C to 550°C, or about 400°C to 500°C, before introducing the second input stream into the adiabatic multi-stage reactor. Alternatively or additionally, prior to introducing the third input stream into the adiabatic multi-stage reactor, the one or more second oxygenates can be heated, for example, to a temperature of about 200°C to 500°C, about 200°C to 500°C, about 375°C to 500°C, about 360°C to 550°C, or about 400°C to 500°C. In some embodiments, the one or more first oxygenates, the one or more second oxygenates, and / or the one or more third oxygenates can be heated by a heat exchanger, e.g., a single furnace. In other embodiments, the one or more first oxygenates, the one or more second oxygenates, and / or the one or more third oxygenates can be heated by two or more heat exchangers, e.g., respective furnaces.

[0103] In some embodiments, the adiabatic staged reactor can have a weight hourly space velocity (WHSV) of about 0.25 to 15. As used herein, "weight hourly space velocity" is defined as the weight of hydrocarbon compound flowing per hour per total weight of catalyst in the staged reactor.

[0104] It should be understood that the net thermodynamics of the oxygenate-to-olefins process depends at least on the oxygenate characteristics, the desired olefin product mixture, and the presence or absence of side reactions. For example, in some embodiments, especially when the recycle rate of light olefins is higher, the net process may be exothermic, requiring heat to be removed from the system. This cooling can be achieved in several ways. For example, a heat exchanger can be used to reduce the temperature of the adiabatic multi-stage reactor output before subjecting it to the final stage, or the olefin oligomerization and cracking stage. This heat exchanger can be separate from the adiabatic multi-stage reactor or can be incorporated into the reactor. The final stage of the reaction can be carried out in a separate vessel, such as in a single reactor downstream of the adiabatic multi-stage reactor, or a side stream from the adiabatic multi-stage reactor can be cooled and then reintroduced into the adiabatic multi-stage reactor. Another approach would be to have lower temperature second and third oxygenate input feeds that cool each reactor bed.

[0105] In some embodiments, particularly when the recycle rate of light olefins is low or zero, or when the first input material contains lower amounts of methanol or light olefins, the net process may be endothermic, requiring the addition of heat to the system. This heating can be achieved in several ways. One approach would be to heat the one or more first oxygenates to a temperature higher than the temperature of the first reactor bed. To maintain the process temperature in one or more early stages of the adiabatic multi-stage reactor, a recycle of some amount of one or more olefins (e.g., recycle of light olefins) may be required. Subsequent additions of one or more oxygenates (e.g., one or more second oxygenates and / or one or more third oxygenates) can be heated to a temperature higher than the highest desired temperature of the adiabatic multi-stage reactor to ensure that the total process temperature before each reaction stage is high enough to simultaneously continue the dehydration of the one or more oxygenates and the oligomerization of olefins present in the reaction mixtures (e.g., the first reaction mixture, the second reaction mixture, and / or the third reaction mixture). By increasing the number of reaction stages, the net recycle of lower olefins can be reduced, possibly to almost negligible values, but the selectivity to the olefins may decrease because the olefins are exposed to the catalyst for a longer period of time.

[0106] An exemplary schematic of a system 100 for converting oxygenates is shown in Figure 1. For simplicity's sake only, this exemplary system 100 will be described with respect to one or more first, second, and third oxygenates being ethanol, and one or more olefins being ethylene. Those skilled in the art will understand that this exemplary system can be used with other oxygenates and olefins, and thus is not limited to ethanol or ethylene.

[0107] In the illustrated system 100, the system 100 includes an ethanol source 102, an optional heat integration subsystem 104, and an adiabatic multi-stage reactor 106. While the adiabatic multi-stage reactor 106 can have more than two reaction stages, in this illustrated example, the adiabatic multi-stage reactor includes three reaction stages. The first reaction stage includes a first reactor bed 108, the second reaction stage includes a second reactor bed 110, and the third reaction stage includes a third reactor bed 112. Each reactor bed 108, 110, 112 includes one or more catalysts. As described in more detail below, in this illustrated system, heated ethanol is fed to the adiabatic multi-stage reactor 106 in three portions. Although the heat integration subsystem can have a variety of configurations, in this illustrated system, the heat integration subsystem includes a preheater configured to preheat ethanol, for example, to a temperature of about 450° C., and a condenser configured to condense an output stream (e.g., the output stream of the single-stage reactor) into a condensed output stream.

[0108] During use, ethanol 102 is introduced into a preheater (not shown) and heated. A first portion of the heated ethanol 102a is then combined with an ethylene recycle stream 114 (e.g., a first stream) to produce a first input feed 116, which is then introduced into a first end 118 (e.g., a first inlet) of the adiabatic multi-stage reactor 106. The first input feed 116 then contacts a first reactor bed 108, thereby maintaining a first temperature of the first reactor bed 108 within a first temperature range and producing a first reaction mixture (not shown). The first reactor bed 108 is designed so that the heat generated from the expected exothermic olefin oligomerization substantially or completely balances the heat absorbed by the dehydration of ethanol.

[0109] A second portion of the heated ethanol is introduced into the adiabatic multi-stage reactor 106 as second input 102b. Upon exiting the first reaction stage, the first reaction mixture (not shown) is mixed with the second input 102b in the adiabatic multi-stage reactor 106 to produce a first effluent (not shown). The first effluent then contacts the second reactor bed 110, thereby maintaining a second temperature of the second reactor bed 110 within a second temperature range and producing a second reaction mixture (not shown). The second reactor bed 110 is designed so that the heat generated from the expected exothermic olefin oligomerization substantially or completely balances the heat absorbed by the dehydration of ethanol to ethylene.

[0110] A third portion of the heated ethanol is introduced into the adiabatic multi-stage reactor 106 as a third input feed 102c. Upon exiting the second reaction stage, the second reaction mixture (not shown) is mixed with the third input feed 102c within the adiabatic multi-stage reactor 106 to produce a second effluent (not shown). The second effluent then contacts the third reactor bed 112, thereby maintaining a second temperature of the third reactor bed 112 within a third temperature range and producing a third reaction mixture 120. The third reactor bed 112 is designed so that the heat generated from the expected exothermic olefin oligomerization substantially or completely balances the heat absorbed by the dehydration of ethanol to ethylene. The third reaction mixture 120 then exits the adiabatic multi-stage reactor 106 at a second end 122 (e.g., an outlet) opposite the first end 118. Those skilled in the art will appreciate that first end 118 and second end 122 may be located at various locations on the adiabatic multi-stage reactor and are therefore not limited to those locations shown in FIG. 1 .

[0111] As further shown in FIG. 1 , system 100 includes a first heat exchanger 124, a single-stage reactor 126, a separation subsystem 128, and a second heat exchanger 130. During use, third reaction mixture 120 is first introduced into first heat exchanger 124 such that the temperature of third reaction mixture 120 is reduced. The resulting cooled third reaction mixture 121 is then introduced as an input feed into single-stage reactor 126. Single-stage reactor 126 includes reactor bed 132 having one or more catalysts such that at least a portion of the ethylene in third reaction mixture 120 is converted to higher carbon number olefins (e.g., C3-C5 olefins). In other words, when third reaction mixture 120 contacts reactor bed 132 of single-stage reactor 126, output stream 134 is produced. Output stream 134 includes one or more product olefins (e.g., C3-C5 olefins) and ethylene.

[0112] Output stream 134 may then optionally be first introduced into a condenser of heat integration subsystem 104. Condensed output stream 136 may then be introduced into separation subsystem 128, which produces first stream 138 and second stream 140 (C3+ olefins). First stream 138 contains ethylene, and second stream contains C3-C5 olefins, water, and by-products (e.g., aromatics and / or saturates). In this illustrated system, first stream 138 is then introduced into second heat exchanger 130 to increase the temperature of the ethylene, which is subsequently mixed with a first portion of ethanol 102a to form first input stream 116. In this manner, at the start of the process, the first input feedstock 116 contains only a first portion of the ethanol 102a, but as the process progresses, the first stream 138 (e.g., a recycle of the produced ethylene) is combined with the first portion of the ethanol 102a upstream of the multi-stage reactor 106, so that the first input stream 116 therefore contains a combination of the ethanol 102a and the recycle 138 of the produced ethylene.

[0113] In some embodiments, a majority of the ethylene is withdrawn from the system rather than being recycled back into the multi-stage reactor. Thus, when a majority of the ethylene is withdrawn from the output stream, it may be desirable to heat the first feedstock, for example, to a temperature of about 450° C., before introducing the ethanol portion into the multi-stage reactor. Heating of the ethanol can be accomplished, for example, by a furnace, electric heater, or other heat source implemented in the system.

[0114] As noted above, in some embodiments, first stream 138 can be ethylene (e.g., ethylene being the most concentrated component of the first stream). In other embodiments, it may be desirable to limit or avoid olefin separation. In such embodiments, the first stream can include a mixture of various olefins. For example, in some embodiments, the first stream can include ethylene and propylene (e.g., ethylene and propylene being the most concentrated components of the first stream). In other embodiments, the first stream can include C2-C4 olefins (e.g., C2-C4 olefins being the most concentrated components). In still other embodiments, the first stream can include C2-C5 olefins. In some embodiments, a portion of the condensed output stream can be added to the first stream before being separated by the separation subsystem.

[0115] In certain embodiments, one or more olefins can be produced directly from C2+ alcohols in a separate reactor using a dehydration-specific catalyst and then used as part of the first input feedstock without separation from unconverted alcohol, produced water, or any by-products.

[0116] In some embodiments, the reactor can have additional streams introduced into the reactor, where the first input material can also include methanol and / or dimethyl ether. An exemplary schematic diagram of an ethanol feed and methanol and / or dimethyl ether feed system for oxygenate conversion is shown in FIG. 2. For simplicity's sake, this exemplary system 200 will be described with respect to two streams that combine to form the first input stream introduced into the adiabatic reactor. More specifically, the first stream is ethanol and the second stream is methanol and / or dimethyl ether. Those skilled in the art will appreciate that this exemplary system can be used with other oxygenates and olefins and is therefore not limited to methanol, dimethyl ether, or ethanol.

[0117] In the illustrated system 200, system 200 includes a methanol source 201, an optional first heat exchanger 203, an ethanol source 202, an optional heat integration subsystem 204, and an adiabatic multi-stage reactor 206. While adiabatic multi-stage reactor 206 can have more than one reaction stage, in this illustrated example, the adiabatic multi-stage reactor includes three reaction stages. The first reaction stage includes a first reactor bed 208, the second reaction stage includes a second reactor bed 210, and the third reaction stage includes a third reactor bed 212. Each reactor bed 208, 210, 212 includes one or more catalysts. As described in more detail below, in this illustrated system, heated methanol is fed to adiabatic multi-stage reactor 206 in one portion, and heated ethanol is fed to adiabatic multi-stage reactor 206 in three portions. In other embodiments, an additional portion of the heated methanol can be fed to an adiabatic multi-stage reactor, e.g., downstream of the first reactor bed. While first heat exchanger 203 can have a variety of configurations, in this illustrated system, the first heat exchanger is configured to preheat the methanol, e.g., to a temperature of about 450°C to 550°C (e.g., about 450°C). Additionally, while heat integration subsystem 204 can have a variety of configurations, the second heat integration subsystem includes a preheater configured to preheat the ethanol, e.g., to a temperature of about 450°C, and a condenser configured to condense the output stream (e.g., the output stream of the single-stage reactor) into a condensed output stream.

[0118] During use, methanol 201 is introduced into a preheater (not shown) and heated, and ethanol 202 is introduced into a preheater (not shown) and heated. A first portion 202a of the heated ethanol is then combined with a heated methanol stream 205 (e.g., a first stream) to produce a first input feed 216, which is then introduced into a first end 218 (e.g., a first inlet) of the adiabatic multi-stage reactor 206. In other embodiments, the heated ethanol first portion 202a and the heated methanol stream 205 may not be introduced into the adiabatic multi-stage reactor 206 as a combined stream, but rather as two separate streams. The first input feed 216 then contacts the first reactor bed 208, thereby maintaining a first temperature of the first reactor bed 208 within a first temperature range and producing a first reaction mixture (not shown). The first reactor bed 208 is designed so that the heat generated from the exothermic conversion of methanol to dimethyl ether, the conversion of methanol and dimethyl ether to olefins, and the potential oligomerization of olefins, substantially or completely balances the heat absorbed by the dehydration of ethanol.

[0119] A second portion of the heated ethanol is introduced into adiabatic multi-stage reactor 206 as second input 202b. Upon exiting the first reaction stage, the first reaction mixture (not shown) is mixed with second input 202b in adiabatic multi-stage reactor 206 to produce a first effluent (not shown). The first effluent then contacts second reactor bed 210, thereby maintaining a second temperature of second reactor bed 210 within a second temperature range and producing a second reaction mixture (not shown). Second reactor bed 210 is designed so that the heat generated from the exothermic conversion of methanol to dimethyl ether, the conversion of methanol and dimethyl ether to olefins, and the potential oligomerization of olefins substantially or completely balances the heat absorbed by the dehydration of ethanol to ethylene.

[0120] A third portion of the heated ethanol is introduced into adiabatic multi-stage reactor 206 as third input 202c. Upon exiting the second reaction stage, the second reaction mixture (not shown) is mixed with second input 202c in adiabatic multi-stage reactor 206 to produce a second effluent (not shown). The second effluent then contacts third reactor bed 212, thereby maintaining a second temperature of third reactor bed 212 within a third temperature range and producing third reaction mixture 220. Third reactor bed 212 is designed so that the heat generated from the expected exothermic olefin oligomerization substantially or completely balances the heat absorbed by the dehydration of ethanol to ethylene. Third reaction mixture 220 then exits adiabatic multi-stage reactor 206 at a second end 222 (e.g., an outlet) opposite first end 218. Those skilled in the art will appreciate that first end 218 and second end 222 may be located in various positions on the adiabatic multi-stage reactor and are therefore not limited to those positions shown in FIG. 2 .

[0121] As further shown in FIG. 2 , system 200 includes a second heat exchanger 224 and a single-stage reactor 226. During use, third reaction mixture 220 is first introduced into second heat exchanger 224 so that the temperature of third reaction mixture 220 is reduced. The resulting cooled third reaction mixture 221 is then introduced as an input feed into single-stage reactor 226. Single-stage reactor 226 includes reactor bed 232 having one or more catalysts such that at least a portion of the ethylene in third reaction mixture 220 is converted to higher carbon number olefins (e.g., C3-C5 olefins). In other words, when third reaction mixture 220 contacts reactor bed 232 of single-stage reactor 226, output stream 234 is produced. Output stream 234 includes one or more product olefins (e.g., C3-C5 olefins) and ethylene.

[0122] Output stream 234 may then optionally be first introduced to a condenser in heat integration subsystem 204. Condensed output stream 236 may then be introduced to a separation subsystem. Although not shown, the separation subsystem may be similar to separation subsystem 128. Additionally, although not shown, a recycle stream of ethanol, such as 114 in FIG. 1, may be generated within system 200 and introduced to adiabatic reactor 206, as described above with respect to FIG. 1.

[0123] An exemplary method for converting one or more oxygenates to one or more olefins can include introducing a first input containing ethanol, water, and methanol and / or olefins into an adiabatic multi-stage reactor, where the temperature of the first input can be about 400°C to 480°C. In this exemplary method, the ethanol can be present in the first input at about 20-25 wt% of the first input, the methanol, ethylene, or other mixed olefins can be present in the first input at about 60-70 wt% of the first input, and the remainder of the first input stream can be water. The temperature of the first reactor bed can be greater than or equal to about 350°C and less than or equal to about 480°C (350°C < first reactor bed temperature < 480°C). Once the first reaction mixture is formed, the first reaction mixture can be combined with a second input of ethanol to form a first effluent, with another portion of the ethanol being at a temperature above about 300°C. The ethanol present in the first effluent is about 15-30% by weight of the first effluent. Water may optionally be added to the second input feed so that the total amount of water in the first effluent does not exceed about 60% by weight. The temperature of the second reactor bed may be about 350°C or higher and about 480°C or lower (350°C < first reactor bed temperature < 480°C). Once the second reaction mixture is formed, the second reaction mixture may be combined with a third input of ethanol to form a second effluent, the ethanol being at a temperature above about 300°C. The ethanol present in the second effluent is about 10-25% by weight of the second effluent. Water may optionally be added to the third input so that the total amount of water in the second effluent does not exceed about 60% by weight. The temperature of the third reactor bed may be about 350°C or higher and about 480°C or lower (350°C < first reactor bed temperature < 480°C). Once the third reaction mixture is formed, the third reaction mixture can then exit the adiabatic multi-stage reactor as an output stream of the adiabatic multi-stage reactor.

[0124] When additional downstream reactor beds are present in the multi-stage reactor, the method can also include the following: Once the third reaction mixture is formed, the third reaction mixture can be combined with a fourth input of ethanol to form a third effluent, the ethanol being at a temperature greater than about 300°C. The ethanol present in the second effluent is about 8-22% by weight of the third effluent. Water may optionally be added to the fourth input so that the total amount of water in the third effluent does not exceed about 60% by weight. The temperature of the fourth reactor bed can be greater than or equal to about 350°C and less than or equal to about 480°C (350°C≦the temperature of the first reactor bed≦480°C). Once the fourth reaction mixture is formed, the fourth reaction mixture can exit the multi-stage reactor as an output stream. Optionally, the output stream can be cooled by a heat exchanger and fed to a fifth reactor bed as a fifth input to the multi-stage reactor, for example, at an input temperature of about 350°C to 400°C. Water may optionally be added to the fifth input stream such that the total amount of water in the fifth feedstock does not exceed about 60% by weight.

[0125] Another exemplary method for converting one or more oxygenates to one or more olefins can include introducing a first input containing ethanol, water, and methanol and / or olefins into an adiabatic multi-stage reactor, where the temperature of the first input can be about 400°C to 480°C. In this exemplary method, the ethanol can be present in the first input at about 25-30 wt% of the first input, the methanol, ethylene, or other mixed olefins can be present in the first input at about 50-60 wt% of the first input, and the remainder of the first input stream can be water. The temperature of the first reactor bed can be about 350°C or higher and about 480°C or lower (350°C < first reactor bed temperature < 480°C). Once the first reaction mixture is formed, the first reaction mixture can be combined with a second input of ethanol to form a first effluent, with another portion of the ethanol being at a temperature above 300°C. The ethanol present in the first effluent is about 20-30% by weight of the first effluent. Water may optionally be added to the second input feed so that the total amount of water in the first effluent does not exceed about 50% by weight. The temperature of the second reactor bed may be about 350°C or higher and about 480°C or lower (350°C < first reactor bed temperature < 480°C). Once the second reaction mixture is formed, the second reaction mixture may be combined with a third input of ethanol to form a second effluent, the ethanol being at a temperature above about 300°C. The ethanol present in the second effluent is about 15-25% by weight of the second effluent. Water may optionally be added to the third input so that the total amount of water in the second effluent does not exceed about 50% by weight. The temperature of the third reactor bed may be about 350°C or higher and about 480°C or lower (350°C < first reactor bed temperature < 480°C). Once the third reaction mixture is formed, the third reaction mixture can then exit the adiabatic multi-stage reactor as an output stream of the adiabatic multi-stage reactor.

[0126] When additional downstream reactor beds are present in the multi-stage reactor, the method can also include the following: Once the third reaction mixture is formed, the third reaction mixture can be combined with a fourth input of ethanol to form a third effluent, the ethanol being at a temperature greater than about 300°C. The ethanol present in the second effluent is about 15-25% by weight of the third effluent. Water may optionally be added to the fourth input so that the total amount of water in the third effluent does not exceed about 50% by weight. The temperature of the fourth reactor bed can be greater than about 350°C and less than about 480°C (350°C≦the temperature of the first reactor bed≦480°C). Once the fourth reaction mixture is formed, the fourth reaction mixture can exit the multi-stage reactor as an output vapor. Optionally, the output stream can be cooled by a heat exchanger and fed to a fifth reactor bed as a fifth input to the multi-stage reactor, e.g., at an input temperature of about 350°C to 400°C. Water may optionally be added to the fifth input stream such that the total amount of water in the fifth feedstock does not exceed about 60% by weight.

[0127] In any of the foregoing exemplary processes described above, when the first input stream comprises at least one or more first oxygenates and one or more first olefins, the net molar ratio of ethylene to ethanol fed across all reaction stages can be, for example, 1:1. This molar ratio can be increased or decreased based on the number of reactor beds in the adiabatic multi-stage reactor. For example, in some embodiments where the multi-stage reactor has more than five reactor beds, the net molar ratio of ethylene to ethanol fed across all reaction stages can be, for example, 1:5 or 1:9.

[0128] The terminology used herein is for the purpose of describing particular embodiments and implementations only and is not intended to be limiting. For example, as used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise.

[0129] In the above description and in the claims, phrases such as "at least one of" or "one or more of" may appear followed by a concatenated list of elements or features. The term "and / or" may also appear in lists of two or more elements or features. Unless otherwise contradicted, implicitly or explicitly by the context of use, such phrases are intended to mean any of the listed elements or features individually, or any of the listed elements or features in combination with any of the other listed elements or features. For example, the phrases "at least one of A and B," "one or more of A and B," and "A and / or B" are intended to mean "A only, B only, or A and B together," respectively. A similar interpretation is intended for lists containing more than two items. For example, the phrases "at least one of A, B, and C," "one or more of A, B, and C," and "A, B, and / or C" are intended to mean "A only, B only, C only, A and B together, A and C together, B and C together, or A, B, and C together," respectively. Use of the term "based on" above and in the claims is intended to mean "based at least in part on," allowing for unrecited features or elements.

[0130] The terms "first" and "second" may be used herein to describe various features / elements (including steps), but these features / elements should not be limited by these terms unless the context indicates otherwise. These terms may be used to distinguish one feature / element from another. Thus, a first feature / element described below could be referred to as a second feature / element, and similarly, a second feature / element described below could be referred to as a first feature / element, without departing from the teachings provided herein.

[0131] As used in this specification and claims, including in the examples, unless expressly specified otherwise, all numbers can be read as if they were preceded by the word "about" or "approximately," even if the term does not explicitly appear. The phrase "about" or "approximately" can be used when describing a size and / or location to indicate that the described value and / or location is within a reasonable expected range of the value and / or location. The word "about" or "approximately" immediately preceding a numerical value refers to a range of plus or minus 10% of that value. For example, "about 50" means 45 to 55, and "about 25,000" means 22,500 to 27,500. Furthermore, the phrases "less than about a value" or "greater than about a value" should be understood in light of the definition of the term "about" provided herein. When a value is disclosed, it is understood that "less than or equal to" that value, "greater than or equal to" that value, and possible ranges between values, as appropriately understood by those of ordinary skill in the art, are also disclosed. For example, if a value "X" is disclosed, "less than or equal to X" as well as "greater than or equal to X" (e.g., where X is a numeric value) is also disclosed. It is understood that throughout this application, data is provided in several different formats, and that this data represents endpoints and starting points, and ranges for any combination of the data points. For example, if a particular data point "10" and a particular data point "15" are disclosed, it is understood that greater than, greater than, less than, less than, less than, and equal to 10 and 15 are considered to be disclosed, as are values ​​between 10 and 15. It is also understood that each unit between two specified units is disclosed. For example, if 10 and 15 are disclosed, then 11, 12, 13, and 14 are also disclosed.

[0132] While various exemplary embodiments have been described above, any of several modifications can be made to the various embodiments without departing from the teachings herein. For example, the order in which various described method steps are performed may often be changed in alternative embodiments, and in other alternative embodiments, one or more method steps may be skipped entirely. Optional features of various device and system embodiments may be included in some embodiments and not in others. Accordingly, the foregoing description has been provided primarily for illustrative purposes and should not be construed as limiting the scope of the claims.

[0133] The examples and descriptions contained herein illustrate, by way of illustration and not limitation, specific embodiments in which the subject matter may be practiced. As noted above, other embodiments may be utilized and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of the present disclosure. Such embodiments of the inventive subject matter may be referred to herein individually or collectively by the term "invention," where more than one is actually disclosed, merely for convenience and without any intention to intentionally limit the scope of the present application to any single invention or inventive concept. Thus, while specific embodiments are illustrated and described herein, any configuration calculated to achieve the same purpose may be substituted for the specific embodiment shown. The present disclosure is intended to cover any and all adaptations or modifications of the various embodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those skilled in the art upon reviewing the above description. The use of the term "based on" in the specification and claims is intended to mean "based at least in part on," allowing for unrecited features or elements.

[0134] The subject matter described herein may be embodied in systems, devices, methods, and / or articles, depending on the desired configuration. The implementations set forth in the foregoing description do not represent all implementations consistent with the subject matter described herein. Instead, they are merely some examples consistent with aspects related to the described subject matter. While some variations have been described in detail herein, other modifications or additions are possible. In particular, additional features and / or variations may be provided in addition to those described herein. For example, the implementations described herein may be directed to various combinations and subcombinations of the disclosed features and / or combinations and subcombinations of certain additional features disclosed herein. Additionally, the logic flow depicted in the accompanying figures and / or described herein does not necessarily require the particular order or sequence shown to achieve desirable results. Other implementations may be within the scope of the following claims.

Claims

1. 1. A process for converting one or more oxygenates to one or more olefins, said process comprising: introducing a first input feed into a first end of an adiabatic multi-stage reactor, said first input feed comprising one or more first oxygenates and one or more first olefins, said multi-stage reactor having at least a first reaction stage and a second reaction stage, said first reaction stage being upstream of said second reaction stage, said first reaction stage having a first reactor bed, and said second reaction stage having a second reactor bed; contacting the first feedstock with the first reactor bed, thereby maintaining a first temperature of the first reactor bed within a first temperature range of about 300°C to 550°C, and producing a first reaction mixture; introducing a second input feed into the multi-stage reactor downstream of the first reaction stage such that upon exiting the first reaction stage, the first reaction mixture combines with the second input feed to produce a first effluent having a different composition than the first reaction mixture, the second input feed comprising one or more second oxygenates; contacting the first effluent with the second reactor bed, thereby maintaining a second temperature of the second reactor bed within a second temperature range of about 300°C to 550°C, and producing a second reaction mixture; A method comprising:

2. the multi-stage reactor has a third reaction stage, the third reaction stage has a third reactor bed, and the process comprises: introducing a third input feed into the multi-stage reactor downstream of the second reaction stage such that upon exiting the second reaction stage, the second reaction mixture combines with the third input feed to produce a second effluent having a different composition than the second reaction mixture, the third input feed comprising one or more third oxygenates; contacting the second effluent with the third reactor bed, thereby maintaining a third temperature of the third reactor bed within a third temperature range of about 300°C to 550°C, and producing a third reaction mixture; The method of claim 1 further comprising:

3. 3. The process of claim 1 or 2, wherein no external heat is added to the multi-stage reactor during and between each reaction stage.

4. 3. The process of claim 1 or 2, wherein no heat is removed from the multi-stage reactor during and between each reaction stage.

5. 5. The method of claim 1, wherein the first effluent is not removed from the multi-stage reactor.

6. 6. The method of claim 1, wherein the second effluent is not removed from the multi-stage reactor.

7. 7. The method of any one of claims 1, 2, 5, and 6, wherein heat is not removed from the first reaction mixture before it is mixed with the second feedstock.

8. 8. The method of any one of claims 1, 2, 5, 6, and 7, wherein heat is not removed from the second reaction mixture before it is removed from the multi-stage reactor or thereafter mixed with the third feedstock.

9. 9. The method of any one of claims 2, 5, 6, 7 and 8, wherein heat is not removed from the third reaction mixture before it is removed from the multi-stage reactor or thereafter mixed with a fourth feedstock.

10. 10. The process of any one of claims 1 to 9, wherein the one or more first oxygenates comprise a predominant first oxygenate, the one or more first olefins comprise a predominant first olefin, the predominant first oxygenate being ethanol, and the predominant first olefin being ethylene.

11. 11. The process of claim 10, wherein the molar ratio of ethylene to ethanol in the first feedstock is from about 0.25 to 10.

12. 12. The process of claim 11, wherein the molar ratio of ethylene to ethanol in the first feedstock is from about 0.25 to 5.

13. 13. The method of any one of claims 1 to 12, wherein the first temperature range is between about 350°C and 500°C.

14. 14. The method of any one of claims 1 to 13, wherein the second temperature range is between about 350°C and 500°C.

15. 15. The method of any one of claims 2 to 14, wherein the third temperature range is between about 350°C and 500°C.

16. 16. The process of any one of claims 1 to 15, wherein at least one of the first reactor bed or the second reactor bed is a fixed bed.

17. 17. The process of any one of claims 2 to 16, wherein the third reactor bed is a fixed bed.

18. 16. The process of any one of claims 1 to 15, wherein at least one of the first reactor bed or the second reactor bed is a fluidized bed.

19. 16. The process of any one of claims 2 to 15, wherein the third reactor bed is a fluidized bed.

20. 16. The process of any one of claims 1 to 15, wherein at least one of the first reactor bed or the second reactor bed is a moving bed.

21. 16. The process of any one of claims 2 to 15, wherein the third reactor bed is a moving bed.

22. 22. The method of any one of claims 1 to 21, wherein the one or more first oxygenates and the one or more second oxygenates are the same.

23. 23. The method of any one of claims 2 to 22, wherein the one or more first oxygenates, the one or more second oxygenates, and the one or more third oxygenates are the same.

24. 24. The method of any one of claims 1 to 23, wherein the one or more first oxygenates comprise one or more C2+ alcohols.

25. 25. The method of any one of claims 1 to 24, wherein the one or more second oxygenates comprise one or more C2+ alcohols.

26. 26. The method of any one of claims 2 to 25, wherein the one or more third oxygenates comprise one or more C2+ alcohols.

27. 27. The method of any one of claims 1 to 26, wherein the one or more first oxygenates comprise a predominant first oxygenate, and the predominant oxygenate is ethanol.

28. 28. The method of any one of claims 1 to 27, wherein the one or more secondary oxygenates comprises a second predominant oxygenate, and the predominant oxygenate is ethanol.

29. 29. The method of any one of claims 2 to 28, wherein the one or more tertiary oxygenates comprise a predominant tertiary oxygenate, and the predominant oxygenate is ethanol.

30. 30. The process of any one of claims 1, 3 to 22, 24, 25, 27, and 28, further comprising introducing the second reaction mixture into a single-stage reactor, the single-stage reactor comprising one or more catalysts; and contacting the second reaction mixture with the one or more catalysts to produce an output stream comprising one or more product olefins.

31. 31. The method of claim 30, further comprising reducing the temperature of the second reaction mixture prior to introducing the second reaction mixture into the single-stage reactor.

32. 32. The method of claim 30 or 31, further comprising introducing the output stream into a separation subsystem to produce a first stream and a second stream.

33. 32. The process of claim 31 , wherein the second stream comprises at least one C3+ olefin.

34. 34. The method of claim 33, wherein said first stream is combined with said one or more first oxygenates to produce said first input material.

35. 35. The process of any one of claims 32 to 34, wherein the first stream comprises a predominant olefin, and the predominant olefin is ethylene.

36. 32. The method of claim 30 or 31, further comprising condensing the output stream into a condensed output stream and introducing the condensed output stream into a separation subsystem to produce a first stream and a second stream.

37. 37. The method of claim 36, wherein said first stream is combined with said one or more first oxygenates to produce said first input material.

38. 38. The process of claim 36 or 37, wherein the first stream comprises a predominant olefin, the predominant olefin being ethylene.

39. 39. The process of any one of claims 36 to 38, wherein the second stream comprises at least one C3+ olefin.

40. 30. The process of any one of claims 2 to 29, further comprising introducing the third reaction mixture into a single-stage reactor, the single-stage reactor comprising one or more catalysts; and contacting the third reaction mixture with the one or more catalysts to produce an output stream comprising one or more product olefins.

41. 41. The method of claim 40, further comprising reducing the temperature of the third reaction mixture prior to introducing the third reaction mixture into the single-stage reactor.

42. 42. The method of claim 40 or 41, further comprising introducing the output stream into a separation system to produce a first stream and a second stream.

43. 35. The method of claim 34, wherein said first stream is combined with said one or more first oxygenates to produce said first input material.

44. 44. The process of claim 42 or 43, wherein the first stream comprises a predominant olefin, the predominant olefin being ethylene.

45. 45. The process of any one of claims 42 to 44, wherein the second stream comprises at least one C3+ olefin.

46. 42. The method of claim 40 or 41, further comprising condensing the output stream into a condensed output stream and introducing the condensed reaction mixture into a separation subsystem to produce a first stream and a second stream.

47. 48. The method of claim 47, wherein said first stream is combined with said one or more first oxygenates to produce said first input material.

48. 48. The method of claim 46 or 47, wherein the first stream comprises a predominant olefin, the predominant olefin being ethylene.

49. 49. The process of any one of claims 46 to 48, wherein the second stream comprises at least one C3+ olefin.

50. 50. The method of any one of claims 1 to 49, further comprising heating the one or more first oxygenates prior to introducing the first input stream into the adiabatic multi-stage reactor.

51. 51. The method of any one of claims 1 to 50, further comprising heating the one or more second oxygenates prior to introducing the second input stream into the adiabatic multi-stage reactor.

52. 52. The method of any one of claims 2 to 51, further comprising heating the one or more third oxygenates prior to introducing the third input stream into the adiabatic multi-stage reactor.

53. 53. The process of any one of claims 1 to 52, wherein the multi-stage reactor is at a gauge pressure of from 0 to about 30 bar.

54. 54. The process of any one of the preceding claims, wherein the multi-stage reactor has a weight hourly space velocity (WHSV) of about 0.25 to 15.

55. 55. The method of any one of claims 1 to 54, wherein at least one of the first reactor bed or the second reactor bed comprises a mixture of catalysts.

56. 56. The method of claim 55, wherein the mixture of catalysts comprises a zeolite and an alcohol dehydration catalyst.

57. 57. The method of any one of claims 2 to 56, wherein the third reactor bed comprises a mixture of catalysts.

58. 58. The method of claim 57, wherein the mixture of catalysts in the third reactor bed comprises a zeolite and an alcohol dehydration catalyst.

59. 59. The method of any one of claims 1 to 58, wherein the second feedstock is introduced into the adiabatic multi-stage reactor at a temperature greater than the temperature of the first reaction mixture.

60. 59. The method of any one of claims 2 to 58, wherein the third charge is introduced into the adiabatic multi-stage reactor at a temperature greater than the temperature of the second reaction mixture.

61. the multi-stage reactor includes one or more additional reaction stages downstream of the third reaction stage, the one or more additional reaction stages each having a corresponding reactor bed, and the process further comprises: introducing a next feedstock into the multi-stage reactor downstream of a previous reaction stage such that upon exiting the previous reaction stage, the previous reaction mixture mixes with the next feedstock to produce an additional effluent having a different composition from the previous reaction mixture, wherein the next feedstock comprises one or more additional oxygenates; contacting the prior effluent with the respective reactor bed of one of the one or more additional reaction stages, thereby maintaining the temperature of the respective reactor bed within a temperature range of about 300°C to 550°C, and producing an additional reaction mixture downstream of the prior reaction stage; 61. The method of any one of claims 2 to 60, further comprising:

62. 62. The method of any one of claims 1 to 61, wherein the one or more first oxygenates comprise ethanol and methanol.

63. 63. The process of any one of claims 1 to 9, 13 to 34, 36, 37, 39 to 43, 45 to 47, and 49 to 62, wherein the one or more first olefins comprise ethylene, propylene, butene, or any combination thereof.

64. 64. The method of any one of claims 1 to 61 and 63, wherein the one or more first oxygenates are free of methanol.

65. 65. The method of any one of claims 1 to 64, wherein the one or more second oxygenates are free of methanol.

66. 66. The method of any one of claims 1 to 65, wherein the one or more third oxygenates are free of methanol.

67. 1. A process for converting one or more oxygenates to one or more olefins, said process comprising: introducing a first input feed into a first end of an adiabatic multi-stage reactor, the first input feed comprising one or more first oxygenates, the one or more first oxygenates comprising ethanol and at least one of methanol or dimethyl ether, the multi-stage reactor having at least a first reaction stage and a second reaction stage, the first reaction stage being upstream of the second reaction stage, the first reaction stage comprising a first reactor bed, and the second reaction stage comprising a second reactor bed; contacting the first feedstock with the first reactor bed, thereby maintaining a first temperature of the first reactor bed within a first temperature range of about 300°C to 550°C, and producing a first reaction mixture; introducing a second input feed into the multi-stage reactor downstream of the first reaction stage such that upon exiting the first reaction stage, the first reaction mixture combines with the second input feed to produce a first effluent having a different composition than the first reaction mixture, the second input feed comprising one or more second oxygenates; contacting the first effluent with the second reactor bed, thereby maintaining a second temperature of the second reactor bed within a second temperature range of about 300°C to 550°C, and producing a second reaction mixture; A method comprising:

68. the multi-stage reactor has a third reaction stage, the third reaction stage has a third reactor bed, and the process comprises: introducing a third input feed into the multi-stage reactor downstream of the second reaction stage such that upon exiting the second reaction stage, the second reaction mixture combines with the third input feed to produce a second effluent having a different composition than the second reaction mixture, the third input feed comprising one or more third oxygenates; contacting the second effluent with the third reactor bed, thereby maintaining a third temperature of the third reactor bed within a third temperature range of about 300°C to 550°C, and producing a third reaction mixture; 68. The method of claim 67, further comprising:

69. 69. The method of claim 67 or 68, wherein the one or more first oxygenates comprise ethanol and methanol.

70. 69. The method of claim 67 or 68, wherein the one or more first oxygenates comprise ethanol or dimethyl ether.

71. 71. The method of claim 70, wherein the one or more first oxygenates further comprise methanol.

72. 72. The method of any one of claims 67 to 71, wherein the one or more second oxygenates comprise ethanol, methanol, or a combination thereof.

73. 73. The method of any one of claims 67 to 72, wherein the one or more second oxygenates are free of methanol.

74. 74. The method of any one of claims 67 to 73, wherein the one or more third oxygenates comprise ethanol, methanol, or a combination thereof.

75. 75. The method of any one of claims 67 to 74, wherein the one or more third oxygenates are free of methanol.

76. 76. A system comprising the adiabatic multi-stage reactor of any one of claims 1 to 75.

77. 1. A process for converting one or more oxygenates to one or more olefins, said process comprising: introducing a first input feed into a first end of an adiabatic multi-stage reactor assembly, said first input feed comprising one or more first oxygenates and at least one or more first olefins and methanol, said multi-stage reactor assembly having at least a first reaction stage and a second reaction stage, said first reaction stage being upstream of said second reaction stage, said first reaction stage having a first reactor bed, and said second reaction stage having a second reactor bed; contacting the first feedstock with the first reactor bed, thereby maintaining a first temperature of the first reactor bed within a first temperature range of about 300°C to 550°C, and producing a first reaction mixture; introducing a second input feed into the multi-stage reactor assembly downstream of the first reaction stage such that upon exiting the first reaction stage, the first reaction mixture combines with the second input feed to produce a first effluent having a different composition than the first reaction mixture, the second input feed comprising one or more second oxygenates; contacting the first effluent with the second reactor bed, thereby maintaining a second temperature of the second reactor bed within a second temperature range of about 300°C to 550°C, and producing a second reaction mixture; A method comprising:

78. the multi-stage reactor assembly having a third reaction stage, the third reaction stage having a third reactor bed, and the process further comprising: introducing a third input feed into the multi-stage reactor assembly downstream of the second reaction stage such that upon exiting the second reaction stage, the second reaction mixture combines with the third input feed to produce a second effluent having a different composition than the second reaction mixture, the third input feed comprising one or more third oxygenates; contacting the second effluent with the third reactor bed, thereby maintaining a third temperature of the third reactor bed within a third temperature range of about 300°C to 550°C, and producing a third reaction mixture; 78. The method of claim 77, further comprising:

79. 80. The method of claim 77 or 78, wherein the multi-stage reactor assembly comprises two or more reactors, the first and second stages being carried out in the first reactor and the third stage being carried out in the second reactor.

80. 80. The method of claim 77 or 78, wherein the multi-stage reactor assembly comprises two or more reactors, the first reactor bed being disposed within a first reactor and the second reactor bed being disposed within a second reactor.

81. 81. The method of claim 80, wherein the third reactor bed is disposed within a third reactor.

82. 82. The method of any one of claims 77 to 81, wherein the first input material comprises one or more first oxygenates, one or more first olefins, and methanol.

83. 82. The method of any one of claims 77 to 81, wherein the first input feed comprises one or more first oxygenates and methanol.

84. 82. The method of any one of claims 77 to 81, wherein the first input material comprises one or more first oxygenates and one or more first olefins.

85. 85. The method of any one of claims 77 to 84, wherein the one or more second oxygenates are free of methanol.

86. 86. The method of any one of claims 78 to 85, wherein the one or more third oxygenates are free of methanol.

87. 87. The process of any one of claims 77 to 86, wherein the one or more first olefins comprise one or more recycled olefins, wherein the one or more recycled olefins comprise ethylene, propylene, butene, pentene, or any combination thereof.

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