Reactor and process for endothermic reactions at high temperatures

Abstract

To provide an endothermic catalytic reactor including a furnace and a reactor.SOLUTION: The endothermic catalytic reactor includes a radiant furnace including a burner for supplying thermal energy to the furnace, and a reactor including an inlet portion and an outlet portion and disposed in the furnace and adapted to receive radiant thermal energy. The reactor includes one or more static helical spirals that define a flow path within the reactor moving from an inlet portion to an outlet portion. The helical spiral can retain the catalyst on its outer surface and provides an unobstructed defined flow path. An inlet port disposed in the inlet portion is adapted to receive a reactive starting material. An outlet port is disposed near the outlet portion and is adapted to discharge product from the reactor. The reactor is adapted to allow the starting material to receive radiant heat energy and interact with the catalyst sufficiently to cause a reaction that converts the starting material into a product.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure is directed to an endothermic catalytic reactor that includes a furnace and a reactor. [Background technology]

[0002] This application claims the benefit of U.S. Patent Application No. 17 / 887,792, filed August 15, 2022, and U.S. Provisional Application No. 63 / 315,808, filed March 2, 2022, both of which are incorporated by reference in their entireties.

[0003] An endothermic process is any process in which the enthalpy, or internal energy, of a system increases. In such a process, a closed system typically absorbs heat energy from its surroundings, which can then be transferred to the system. For example, if more energy is required to break bonds than is released, energy is taken up and an endothermic reaction occurs. Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides an endothermic catalytic reaction apparatus that includes a radiant furnace and an endothermic reactor. [Means for solving the problem]

[0005] The present disclosure provides an endothermic catalytic reaction apparatus including a radiant furnace and an endothermic reactor. The radiant furnace includes a burner adapted to provide thermal energy to the furnace. The reactor has an inlet portion and an outlet portion and is located within the furnace and adapted to receive radiant heat energy from the furnace. The reactor includes one or more static helical spirals that define a flow path within the reactor so that materials can move from the inlet portion to the outlet portion according to a defined flow path. The helical spirals can be adapted to support a catalyst on their outer surface. One or more inlet ports are located in the inlet portion and adapted to receive reactive starting materials. The outlet port is located on or near the outlet portion and adapted to discharge products from the reactor. The reactor is adapted to allow the starting materials to receive radiant heat energy and interact with the catalyst sufficiently to cause a reaction that converts the starting materials to products. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a front view of a reactor according to the present disclosure. [Figure 2] FIG. 1 is a front view of a reactor according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0007] It should be understood that the present disclosure contemplates various alternative modifications and step sequences unless expressly specified to the contrary. As a non-limiting example, FIGS. 1 and 2 depict the axis of reactor 105 in a vertical position, with reactant flow proceeding downward, although this is not required. The axis of reactor 105 may be vertical, horizontal, or in any orientation suitable for implementation. Accordingly, unless otherwise indicated, the numerical parameters set forth in the following specification and appended claims are approximations that may vary depending upon the desired properties to be obtained. At the very least, and not as an attempt to limit the scope of the claims by the application of the doctrine of equivalents, each numerical parameter should be construed, at least in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0008] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the present disclosure are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible, however, any numerical value inherently contains certain errors necessarily resulting from the standard variation found in their respective testing measurements.

[0009] It should also be understood that any numerical range recited herein is intended to include all subranges subsumed therein. For example, a range of "1 to 10" is intended to include all subranges between (and including) the stated minimum of 1 and the stated maximum of 10, i.e., ranges having a minimum of 1 or more and a maximum of 10 or less.

[0010] All ranges are inclusive and combinable. For example, the term "in the range of 0.06 to 0.25 wt.%, or 0.06 to 0.08 wt.%" includes 0.06 to 0.25 wt.%, 0.06 to 0.08 wt.%, and 0.08 to 0.25 wt.%, respectively. Furthermore, when ranges are given, any endpoints of those ranges and / or numbers specified within those ranges can be combined within the scope of the present disclosure.

[0011] As used herein, unless expressly specified otherwise, all numerical values, such as those representing values, ranges, amounts, or percentages, may be read as if preceded by the word "about," even if the term is not explicitly stated. Unless otherwise stated, the plural encompasses the singular and vice versa. As used herein, the term "comprises" and similar terms mean "including but not limited to."

[0012] As used herein, the transition term "comprising" (and other comparable terms, e.g., "containing" and "including") is "open-ended" and can include unspecified materials. Although described with the term "comprising," the terms "consisting essentially of" and "consisting of" are also within the scope of this disclosure.

[0013] As used herein, the articles "a," "an," and "the" include plural references unless expressly and unambiguously limited to one referent.

[0014] As used herein, the term "defined path" refers to a spiral path through the reactor that defines a distance from the surface of the helical spiral and the interior of the reactor wall and the outer surface of an optional central shaft that extends along the central axis of the reactor.

[0015] As used herein, the term "endothermic reactor" refers to a reactor adapted to allow a chemical reaction to occur that absorbs thermal energy or heat from its environment. The absorbed energy provides the activation energy for the chemical reaction to occur.

[0016] As used herein, the term "helical spiral" refers to a spiral blade that can be coiled around a shaft. A central shaft can be used to establish and maintain the helical spiral, but is not required for the process. The coiling must be such that there is no central hole for the process flow to short-circuit.

[0017] As used herein, the term "linear velocity" refers to the distance traveled by a gas in a given amount of time.

[0018] As used herein, the term "mass flow rate" refers to the mass of a liquid substance passing per unit time. The SI unit is kilograms per second. Mass flow rate is directly dependent on the density, velocity of the liquid, and area of ​​the cross section. Mass flow rate can be determined according to the following formula:

[0019] m=ρVA (where ρ = density of the fluid, V = velocity of the fluid, and A = cross-sectional area.)

[0020] As used herein, the term "Nusselt number" refers to the ratio of convective to conductive heat transfer at a boundary in a fluid. Nusselt number values ​​represent heat transfer by pure conduction. Values ​​between 1 and 10 are characteristic of laminar flow. Larger Nusselt numbers correspond to more vigorous convection, with turbulent flow typically ranging from 100 to 1000.

[0021] As used herein, the term "radiant furnace" refers to a direct heater or direct-fired heater used to provide thermal energy or heat to a reactor. They are used to supply heat to a process. Radiant furnace designs can vary based on the type of fuel and the method of introducing combustion air. Heat is generated by mixing fuel with air or oxygen or from electrical energy. Residual heat may exit the furnace as flue gases.

[0022] As used herein, the term "Reynolds number" refers to the dimensionless ratio of inertial forces to viscous forces in a fluid that undergoes relative internal movement due to different fluid velocities. The Reynolds number helps predict flow patterns in different fluid flow situations. At low Reynolds numbers, the flow tends to be dominated by laminar flow, while at high Reynolds numbers, the flow tends to be turbulent. At Reynolds numbers below about 2,000, flow in pipes is generally laminar, while at values ​​above 3,000, the flow is usually turbulent.

[0023] As used herein, the term "volumetric flow rate" refers to the volume of fluid passing a specified point per unit of time. Volumetric flow rate can be determined according to the following formula: Q=AV (where Q is the volumetric flow rate, A is the cross-sectional area occupied by the flowing material, and V is the average velocity of the flow.)

[0024] Disclosed herein is an endothermic catalytic reaction apparatus including a radiant furnace and a reactor. The radiant furnace includes a burner adapted to provide thermal energy to the furnace. The reactor has a reactant inlet and an outlet and is disposed within the furnace and adapted to receive radiant heat energy from the furnace. Within the reactor are one or more static helical spirals disposed within the reactor to allow materials to travel along a defined path from the reactant inlet to the outlet. The helical spirals may be adapted to support a catalyst on their outer surface. One or more inlet ports are located in the inlet portion of the reactor and adapted to receive reactive starting materials. The reactor includes one or more outlet ports on or near the outlet portion adapted to discharge products from the reactor. The reactor is adapted to allow the starting materials to receive radiant heat energy and interact with the catalyst sufficiently to cause a reaction that converts the starting materials to products.

[0025] As shown in FIG. 1 , reactor 100 includes an endothermic reactor 105 and a radiant furnace 110 (shown in dashed lines) that includes a flue 108. Reactants are provided to endothermic reactor 105 via reactant supply line 120 and can optionally be heated by flowing through optional heat exchanger 130 and optional heat exchanger 180 before being transferred to endothermic reactor 105 at an inlet portion 135 of reactor 105 (heat exchangers 130 and 180 are optional and can be utilized depending on the process being carried out in reactor 105). As shown, reactant supply line 120 travels through a shell side 182 of heat exchanger 180. Radiant furnace 110 encases substantially all of endothermic reactor 105 and includes a burner 140 (shown in dashed lines) that can combust combustible material from line 145 or, alternatively, can be an electric heating element within radiant furnace 110.

[0026] The endothermic reactor 105 includes a static helical spiral 150 disposed within the endothermic reactor 105 around a central shaft 107 and including a defined path adapted to allow reactants to travel along the defined path from the inlet portion 135 to the product discharge 160. The helical spiral 150 has a thickness 157 as described herein. The helical spiral 150 may be adapted to include a catalyst on its outer surface, a first surface 162, and a second surface 164. The radiant furnace 105 provides sufficient thermal energy to allow the reactants to be converted to products through interaction with the catalyst included on the first surface 162 and the second surface 164 of the helical spiral 150, either by direct conversion or catalytic reaction. The effluent from the product discharge 160 passes through the tubes 184 of the heat exchanger 180, heating the reactant contents within the shell side 182. The reactants may be heated sufficiently to leave heat exchanger 130 in a gaseous or vapor state and to a temperature approaching the reaction temperature when they leave heat exchanger 180 and enter endothermic reactor 105 .

[0027] The flow through the heat exchanger 180 can be counter-current as shown in FIG. 1, with the reactants flowing through the reactant supply line 120 in a direction shown as first flow direction 181 and the product stream flowing through the product discharge line 160 in a direction shown as second flow direction 182.

[0028] A catalyst can be used as described herein to increase the reaction rate of the process in reactor 105. A catalyst may not alter the maximum conversion at a given temperature. In some cases, given the efficient energy transport associated with the highly turbulent spiral reactant flow and the high temperatures achievable in the radiant furnace 110, direct conversion, such as acceptable process performance, can be obtained without a catalyst.

[0029] The products exiting tubes 184 of heat exchanger 180 can be separated in separator 170, which can produce several separated streams, shown as non-limiting exemplary streams 172, 174, and overhead stream 188. One of streams 172 and 174 can be a primarily organic stream, while the other can be an aqueous stream. Non-condensable materials can be removed in separator 170 via overhead stream 188. If the non-condensable materials are combustible, they can be used in burner 140, a combustion burner, after being mixed with other combustible materials or after being used alone in line 145.

[0030] As shown in Figure 2, where similar features in Figure 1 are numbered the same, reactor 200 includes an endothermic reactor 105 and a radiant furnace 110 (shown in dashed lines) that includes a flue 108. Reactants are provided to endothermic reactor 105 via reactant supply line 120, optionally heated by flowing through heat exchanger 130 and optional heat exchanger 180, and then transferred to endothermic reactor 105 at an inlet portion 135 of reactor 105. As shown, reactant supply line 120 travels through a shell side 182 of heat exchanger 180. Radiant furnace 110 encases substantially all of endothermic reactor 105 and includes a burner 140 (shown in dashed lines) that can combustible materials or, alternatively, can be an electric heating element within radiant furnace 110.

[0031] The endothermic reactor 105 includes a first static helical spiral 150 and a second helical spiral 152, which may be disposed within the endothermic reactor 105 around a central shaft 107 and adapted to allow reactants to travel from an inlet portion 135 to a product discharge 160 according to a defined path. The helical spirals 150 and 152 may have thicknesses 158 and 157, respectively, as described herein. The defined path may be adapted to include catalysts on its outer surfaces, a first surface 162 and a third surface 166, and a second surface 164 and a fourth surface 168, respectively. The radiant furnace 105 provides sufficient thermal energy to allow the reactants to be converted to products through interaction with the catalysts included on the first surface 162, the second surface 164, the third surface 166, and the fourth surface 168 of the helical spirals 150 and 152, either by direct conversion or catalytic reaction. The effluent from product exhaust 160 passes through tubes 184 of heat exchanger 180, heating the reactant contents in shell side 182. The reactants may be heated sufficiently to leave heat exchanger 130 in a gaseous or vapor state and to a temperature approaching the reaction temperature when they leave heat exchanger 180 and enter endothermic reactor 105.

[0032] The flow through the heat exchanger 180 can be counter-current as shown in FIG. 1, with the reactants flowing through the reactant supply line 120 in a direction shown as first flow direction 181 and the product stream flowing through the product discharge line 160 in a direction shown as second flow direction 182.

[0033] The products exiting tubes 184 of heat exchanger 180 can be separated in separator 170, which can produce several separated streams, shown as non-limiting exemplary streams 172, 174, and overhead stream 188. One of streams 172 and 174 can be a predominantly organic stream, while the other can be a predominantly aqueous stream. Non-condensable materials can be removed in separator 170 via overhead stream 188. If the non-condensable materials are combustible, they can be used in burner 140, a combustion burner, after being mixed with other combustible materials or after being used alone in line 145.

[0034] As shown in Figures 1 and 2, spiral flow along a defined path at high velocity and against the reactor wall can provide excellent energy transfer between the reactor wall and the reactants, regardless of the reactor orientation (vertical, horizontal, or inclined). This wall-to-reactant transport can be so efficient that the overall transport between the radioactive furnace and the reactants can be limited only by the thermal conductivity and the thickness of the reactor wall.

[0035] The starting materials can pass through a heat exchanger before entering reactor 105 so that they can enter reactor 105 in a gaseous or vapor state at temperatures from 225° C., such as 275° C., 325° C., or 425° C., up to 725° C., such as 675° C. or 625° C. The temperature of the starting materials entering reactor 105 can be any value or range between any of the above values.

[0036] The starting materials may be mixed with superheated steam prior to entering the reactor 105 to help achieve the desired temperature and flow characteristics while passing through a defined flow path through the reactor 105.

[0037] The dimensions of the endothermic reactor 105, the defined pathways through the endothermic reactor 105, and the flow rates of reactants or starting materials into the reactor 105, as well as the flow rates of products from the reactor 105, can be tailored to the particular process employed therein. By way of non-limiting example, the reactant feed lines 120 can enter the reactor 105 through ports that can have any suitable cross-sectional shape, non-limiting examples being circular, oval, square, rectangular, or parallelogram. Other suitable shapes for the reactor 105 include barrel or hourglass shapes. The cross-sectional area of ​​the ports can be at least 0.5 m 2 For example, 1m 2 or 2m 2 etc., up to 6m 2 Up to, for example, 5m 2 or 4m 2 etc. The cross-sectional area of ​​the ports for the starting materials entering reactor 105 can be any value or range between any of the above values.

[0038] The reactor 105 may be cylindrical and enclosed at both ends. As shown, the reactor 105 may include a static helical spiral, as shown in FIG. 1, or a static helical spiral with multiple parallel helical spirals, as shown in FIG. 2, which has two parallel helical spirals. Both ends have ports for receiving and discharging reactant streams. The spirals may extend from an optional central pillar to a generally cylindrical wall. The walls may be made of a metal with high thermal conductivity and a minimum thickness necessary for stability at the reaction temperature. The reactor 105 is adapted to allow the starting materials to receive radiant heat energy and interact with the catalyst sufficiently to initiate a reaction that converts the starting materials to products. The helical spiral-reactor wall combination may allow reactants to flow at high velocities, i.e., turbulent, relative to the reactor wall, which may affect energy transfer between the wall and the reactant stream.

[0039] The inner diameter of reactor 105 can be selected based on the particular process employed therein. The reactor diameter can be at least 1 m, such as 3 m or 4 m, and can be up to 10 m, such as 7 m or 4 m. The diameter of reactor 105 can be any value or range between any of the above values.

[0040] In many configurations for reactor 105, the reactor walls can be tapered, which can reduce leakage where the ends of the spiral meet the wall. This configuration is similar to a proper tapered stopper and results in less leakage than a straight-sided one.

[0041] If the reactor 105 is barrel or hourglass shaped, the helical spiral can be constructed first, and then the reactor walls can be "mummy-wrapped" around the helical spiral.

[0042] The single spiral shown in Figure 1 can alternatively be achieved without the central shaft 107. This alternative approach can be used if the width of the spiral surface is wide enough to cover the diameter of the reactor, thus avoiding short circuits along the central axis.

[0043] The helical spirals, shown as 150 and 152 in FIGS. 1 and 2 , can have any suitable number of revolutions, so long as they occur in the reactant supply line 120 that provides reactants or starting materials to the reactor 105 and terminates in the product outlet 160. The helical spiral can have at least 1.5 revolutions, such as 2 or 2.5 revolutions, and can have up to 6.5 revolutions, such as 5.5, 5, or 4.5 revolutions. The number of revolutions of the helical spiral can be any value or range between any of the above values. As one skilled in the art will appreciate, a 0.5 revolution would place the reactant supply line 120 and product outlet 160 on the same side of the reactor 105, while a full revolution would place the reactant supply line 120 and product outlet 160 on opposite sides of the reactor 105. The number of revolutions of the helical spiral depends on the process employed and the location and orientation of the reactor 105 and associated equipment.

[0044] The width of the helical spirals 150 and 152 can be the same as or approximately the same as the inner diameter of the reactor 105 so that there is sufficient fit between the edges of the spirals and the walls of the reactor 105 so that leakage of reactants or starting materials from the desired helical flow (defined path) is minimized.

[0045] The pitch of the helical spiral, shown as 150 and 152 in Figures 1 and 2, can be any pitch that allows the helical spiral to traverse from reactant supply line 120 to provide reactants or starting materials to reactor 105 and product discharge 160, and can be selected based on the particular process employed therein. The pitch of the helical spiral can be at least 0.25 m, such as 0.5 m or 0.75 m, and can be up to 5 m, such as 4 m, 3 m, or 2 m. The pitch of the helical spiral can be any value or range between any of the above values.

[0046] Reactor 105, helical spirals 150 and 152, and other components of reactor 100 and reactor 200 can be constructed of any material that is stable in the presence of the processes carried out therein and does not degrade due to the temperatures and pressures used. Non-limiting examples of suitable materials of construction include 304 stainless steel, 316 stainless steel, 316L stainless steel, copper, aluminum, Alloy A-286, Alloy 20, Alloy 230, Alloy 400, Alloy 600, Alloy 625, Alloy B-2, Alloy B-3, Alloy C-276, Nickel 200, Titanium Grades 2, 3, 4, and 7, Zirconium 702, Zirconium 705, and combinations thereof. The walls of reactor 105 can be made of a material with a suitably high thermal conductivity, such as copper or aluminum, so that the walls readily transfer thermal energy or heat from the furnace to the contents of reactor 105.

[0047] As noted above, one or more helical spirals, shown at 150 in FIG. 1 and 150 and 152 in FIG. 2 , can be adapted to include a catalyst on their exterior surfaces, shown at upper surfaces 162 and 166 and lower surfaces 164 and 168, respectively. The specific catalyst varies depending on the process being carried out in reactor 105. By way of non-limiting example, the catalyst can be deposited on the exterior surface and thermally aged. This can be achieved by embedding a catalyst containing nanoparticles on the exterior surface through a redox reaction at a solid-solution interface; embedding the catalyst in a polished, perforated, or rigid mesh material placed on the exterior surface; supporting the catalyst on a stable support material with a high specific surface area, non-limiting examples of which include alumina, silica, zeolite, and carbon, allowing the catalyst's high specific surface area to maintain high catalytic activity; and other methods known in the art. Regardless of how the catalyst is retained on the exterior surface, the catalyst remains isolated from the defined flow path and unobstructed, thereby enabling high volumes and high flow rates to be maintained, as described above.

[0048] The configuration of catalyst on a helical spiral, where the catalyst is on the outer surface of the helical spiral and not positioned to obstruct the flow of reactants or starting materials along the defined flow path, avoids flow resistance and pressure drop resulting from the process stream (reactants and / or starting materials) passing through small gaps or spaces between catalyst particles. In other words, the reactants or starting materials do not pass through a catalyst bed that obstructs the defined flow path. This configuration provides an unobstructed path for the reactants or starting materials along the defined flow path. This design can enable achieving the Reynolds and Nusselt numbers that characterize the flow and heat transfer characteristics described herein.

[0049] The thickness of the helical spiral, shown as 157 in Figures 1 and 2, can be any thickness that provides sufficient structural integrity to the helical spiral in the desired process, but not so thick as to interfere with heat transfer or defined flow paths. As a non-limiting example, the thickness of the helical spiral can be 0.3 cm, e.g., 1 cm or 2 cm, or up to 5 cm, e.g., 4 cm. The thickness of the helical spiral can be any value or range between any of the above values.

[0050] The reactor 105 can include multiple helical spirals, as shown in Figure 2, where two helical spirals 150 and 152 are shown. When multiple helical spirals are used, the spacing between one helical spiral and the nearest helical spiral is often equidistant to provide the most efficient flow along the defined path. The spacing between the helical spirals can vary from equidistant, which can result in reduced flow efficiency.

[0051] As shown in FIG. 2, product discharge 160 provides a path for the outlet streams from both of the two parallel spirals 150 and 152, where both are discharged into product discharge 160 to exit reactor 105.

[0052] The starting materials or reactants can optionally include steam to achieve desired physical parameters, as described below. The ratio of steam to starting material or reactant can be at least 0.25:1, such as 0.5:1 or 0.75:1, and can be up to 4:1, such as 3:1, 2:1, or 1.5:1. The ratio of steam to starting material or reactant can be any value or range between any of the above values.

[0053] The pressure within the reactor 105 can be any pressure that promotes the flow or starting materials or reactants along a defined path and promotes their conversion to products or reactants. The pressure within the reactor 105 can be at least 0.25 atm, such as 0.5 atm or 0.75 atm, and can be up to 10 atm, such as 8 atm, 6 atm, 4 atm, or 2 atm. The desired pressure can be achieved and adjusted using appropriate valves and compressors, as known to those skilled in the art. The pressure in the reactor 105 can be any value or range between any of the above values.

[0054] The starting materials and optional steam can have a mass flow rate through reactor 105 from 20 kg / sec, such as 25 kg / sec or 30 kg / sec, up to 150 kg / sec, such as 140 kg / sec or 125 kg / sec, etc. The mass flow rate of the starting materials and optional steam flowing through reactor 105 can be any value or range between any of the above values.

[0055] The starting materials and optional vapors can have a volumetric flow rate through reactor 105 of from 500 μL / sec, e.g., 600 μL / sec or 700 μL / sec, up to 1,000 μL / sec, e.g., 900 μL / sec or 500 μL / sec. The volumetric flow rates of the starting materials and any vapors flowing through reactor 105 can be any value or range between any of the above values.

[0056] The starting material and optional steam can have a linear velocity through the reactor 105 of from 15 m / s, such as 20 m / s or 25 m / s, up to 35 m / s, such as 33 m / s or 30 m / s. The linear velocity of the starting material and optional steam flowing through the reactor 105 can be any value or range between any of the above values.

[0057] The dimensions of the defined path through the endothermic reactor 105 and the flow rates of reactants or starting materials into the reactor 105, as well as the flow rate of products from the reactor 105, are designed to achieve specific flow parameters. As a non-limiting example, the starting material is gaseous when it enters the reactor 105, and the starting material flows along the defined path such that it has a Reynolds number of from 1,000,000, e.g., 2,000,000 or 3,000,000, to 15,000,000, e.g., 12,500,000 or 10,000,000. The Reynolds number of the starting material flowing through the reactor 105 can be any value or range between any of the above values.

[0058] The above flow parameters can be achieved when a catalyst configuration is used on the outer surface of the helical spiral, rather than in a location that would obstruct the flow of reactants or starting materials along the defined flow path. As noted above, this configuration avoids the flow resistance and pressure drop that would result from the process stream (reactants and / or starting materials) passing through small gaps or spaces between catalyst particles. In other words, the reactants or starting materials are not passed through the catalyst bed, which would obstruct the defined flow path.

[0059] As a non-limiting example, the starting material is gaseous when it enters reactor 105, and the starting material has a Nusselt number of from 3,000, e.g., 4,000 or 5,000, to 15,000, e.g., 12,500 or 10,000, and flows along a defined path. The Nusselt number of the starting material flowing through reactor 105 can be any value or range between any of the above values.

[0060] The radiant furnace 110 included in reactor 100 and reactor 200 can generate any suitable temperature for the process employed therein, which can be a temperature from 350° C., e.g., 400° C. or 450° C., up to 900° C., e.g., 850° C., 800° C. or 750° C. The radiant furnace temperature can be any value or range between any of the above values.

[0061] As noted above, the starting materials may be gaseous as they enter the reactor 105 and flow along a defined path. Thermal energy or heat from the furnace may be readily transferred to the contents of the reactor 105, and the high flow rates, as indicated by the Reynolds and Nusselt numbers, provide sufficient and constant rotation at the catalyst surface of the helical spiral to allow the starting materials to be converted into products.

[0062] The conversion of starting materials to products in reactor 105 varies depending on the process and process conditions used and may be at least 10%, such as 25%, 40%, 50%, 60%, 70%, 75%, or 80%, and may be up to 100%, such as 99%, 95%, or 90%. The conversion of starting materials to products may be any value or range between any of the above values.

[0063] An outlet stream containing products and optionally unreacted starting materials, optionally non-condensables, and optional vapor can exit the reactor 105 via line 160 and enter a heat exchanger 180. For ease of illustration, the heat exchanger 180 is shown vertically in FIGS. 1 and 2 and generally parallel to the reactor 105. For particularly high-volume applications, the heat exchanger 180 can be horizontally oriented. The outlet stream can be directed to the tube side 184 of the heat exchanger 180 and used to heat starting materials or reactants transported from the reactant supply line 120 to the shell side 182 of the heat exchanger before entering the inlet portion 135 of the reactor 105. The relative flow patterns of the shell side 182 and the tube side 184 can be in the same direction or in opposite or countercurrent directions, depending on the process employed. The outlet stream leaves the tubes 184 of the heat exchanger 180 and enters the separator 170. Separator 170 separates the outlet stream into several separated streams, shown as non-limiting exemplary streams 172, 174, and overhead stream 188. One of streams 172 and 174 comprises a primarily organic stream and the other a primarily aqueous stream. Non-condensable materials can be removed within separator 170 via overhead stream 188. If the non-condensable materials are flammable, they can be used in burner 140, a combustion burner, after being mixed with other flammable materials or used alone in line 145.

[0064] Conventional methods, such as distillation columns, can be used to isolate unreacted starting materials or reactants from the products in the predominantly organic stream and any unreacted starting materials or reactants from the water in the predominantly aqueous stream. The products can then be containerized as needed, the unreacted starting materials or reactants returned to the reactant feed line 120, and the water can be regenerated to steam or superheated steam and used as described above.

[0065] Accordingly, the present disclosure provides a method for converting reactants into products, comprising the steps of: passing the reactants through a heat exchanger to provide heated reactants, the heated reactants being in a gaseous or vapor state and optionally including superheated vapor as described above at a temperature as described above; providing the heated reactants to an endothermic catalytic reactor as described above, which may include a burner as described above, the radiant furnace adapted to provide thermal energy or heat to the furnace; a reactor having any of the configurations described above, disposed within the furnace and having reactant supply lines and a product discharge adapted to receive radiant thermal energy or heat from the furnace; and a reactor disposed within the reactor such that material can follow a defined path from the reactor supply lines to the product discharge. the reactor comprises one or more static helical spirals that may be adapted to hold a catalyst as described above, one or more inlet ports on the inlet portion adapted to receive reactants from a reactant supply line, and a product discharge port on or near the outlet portion adapted to discharge products from the reactor, wherein the reactor is adapted so that the reactants receive radiant heat energy and interact with the catalyst sufficiently to cause a reaction that converts the reactants to products, the endothermic catalytic reactor optionally being adapted to separate optional one or more second combustible materials from the reaction occurring in the reactor and provide the optional one or more second combustible materials to a burner; and separating the products from non-product materials as described above.

[0066] As will be apparent to those skilled in the art, the endothermic catalytic reactors described herein can be used in several endothermic processes, non-limiting examples of which include cracking alkanes, the reaction of thionyl chloride with cobalt(II) sulfate heptahydrate, and thermal decomposition reactions. Specific non-limiting examples also include the conversion of ethane to ethylene, propane to propylene, ethylbenzene to styrene, ethyltoluene to vinyltoluene, and diethylbenzene to divinylbenzene.

[0067] As a non-limiting detailed example, the disclosure provides a method for producing styrene, comprising the steps of: passing a reactant stream comprising ethylbenzene and optionally superheated steam through a heat exchanger to provide a heated reactant stream as described above at a temperature of from 450°C, e.g., 475°C or 525°C, up to 725°C, e.g., 675°C or 625°C; providing the reactant stream to an endothermic catalytic reactor as described above, the reactor having any of the configurations described above, including a radiant furnace including a burner as described above adapted to provide thermal energy to the furnace; a reactor located within the furnace and adapted to receive radiant thermal energy or heat from the furnace, the reactor having reactant supply lines and a product discharge; and one or more static helical spirals including a defined pathway positioned within the reactor such that material can follow the defined pathway to travel from the reactant supply lines to the product discharge. the helical spiral comprising a helical spiral that can be adapted to carry a catalyst on its exterior surface, as described above; one or more inlet ports on the inlet portion adapted to receive heated reactants; and a product discharge on or near the outlet portion adapted to discharge a product stream comprising styrene from the reactor, the reactor being adapted to allow the heated reactant stream to receive radiant heat energy and interact with the catalyst sufficiently to cause a reaction that converts ethylbenzene to styrene and by-product hydrogen, the product stream comprising styrene, hydrogen, optionally unreacted ethylbenzene, and optionally steam; separating the product stream into a primarily aqueous phase, a primarily organic phase, and a non-condensable overhead comprising hydrogen; and separating styrene from the primarily organic phase as described above, and optionally from the primarily aqueous phase as described above.

[0068] As a non-limiting example, if the large-scale production of styrene from ethylbenzene is desired, the required flow rate may be too high to pass through a tube filled with catalyst particles, i.e., the catalyst bed described above. As noted above, at sufficiently high flow rates, energy transfer may be efficient enough that any radial temperature and / or concentration gradients are negligible. In the reactor designs described herein, a clear, unobstructed, high-velocity path for the reactant flow is provided by coating and / or impregnating the spiral flight(s) of the static mixer with catalyst.

[0069] As mentioned above, this wall-to-reactant transport can be so efficient that the overall transport between the radioactive furnace and the reactants can be limited only by the thermal conductivity and thickness of the reactor wall.

[0070] The conversion of ethylbenzene to styrene can be at least 70%, such as 75% or 80%, and can be up to 100%, such as 99%, 95%, or 90%. The conversion of ethylbenzene to styrene can be any value or range between any of the above values.

[0071] As above, the styrene can then be separated from the product stream.

[0072] The non-condensable hydrogen by-product can be containerized using methods known in the art for subsequent use, non-limiting examples being used to generate electrical energy that can be used in electric vehicles, fuel cells, batteries, or used to provide needed energy when burner 140 is electric. As another alternative, hydrogen can be used as a combustible material in line 145 when burner 140 is a combustion burner.

[0073] As noted above, the endothermic catalytic reactors and methods described herein can be used to provide a number of such products.

[0074] While specific embodiments of the present invention have been described above for purposes of illustration, it will be apparent to those skilled in the art that many changes in the details of the disclosure can be made without departing from the invention as defined in the appended claims.

Claims

1. An endothermic catalytic reactor, comprising: a radiant furnace including a burner that provides thermal energy to the furnace; a reactor having an inlet portion and an outlet portion, the reactor being positioned within the furnace and configured to receive radiant heat energy from the furnace; a defined pathway extending through the reactor from the inlet portion to the outlet portion to form one or more helical spirals, the pathway not being in a position to obstruct the flow of reactants or starting materials; one or more inlet ports located in the inlet portion for receiving reactive starting materials; an outlet port on or near the outlet section through which product is discharged from the reactor; Equipped with The reactor is an endothermic catalytic reactor in which the starting material receives radiant heat energy and interacts with a catalyst sufficiently to cause a reaction that converts the starting material into a product.

2. 10. The endothermic catalytic reactor of claim 1, wherein a catalyst is carried on an exterior surface of the defined passages.

3. 10. The endothermic catalytic reactor of claim 1, wherein the reactor does not include a catalyst bed along the defined path.

4. 10. The endothermic catalytic reactor of claim 1, wherein the starting material is a gas and flows along the defined path such that the starting material has a Reynolds number of 1,000,000 to 15,000,000.

5. 10. The endothermic catalytic reactor of claim 1, wherein the starting material is a gas and flows along the defined path such that the starting material has a Nusselt number of 3,000 to 15,000.

6. 10. The endothermic catalytic reactor of claim 1, wherein the starting materials pass through a heat exchanger before entering the reactor and enter the reactor at a temperature of from 225°C to 725°C.

7. 10. The endothermic catalytic reactor of claim 1, wherein the starting material has a mass flow rate through the reactor of 20 kg / sec to 150 kg / sec.

8. 10. The endothermic catalytic reactor of claim 1, wherein the starting material has a volumetric flow rate through the reactor of 500 L / sec to 1,000 L / sec.

9. 10. The endothermic catalytic reactor of claim 1, wherein the starting material has a linear velocity through the reactor of 15 m / sec to 35 m / sec.

10. 10. The endothermic catalytic reactor of claim 1, wherein the radiant furnace has a temperature of 350°C to 900°C.

11. 10. The endothermic catalytic reactor of claim 1, wherein the conversion of starting materials to products is at least 10%.

12. 10. The endothermic catalytic reactor of claim 1, wherein the starting materials and the products are in the vapor phase within the reactor.

13. 10. The endothermic catalytic reactor of claim 1 further comprising a separator for separating the products from non-product materials.

14. 14. The endothermic catalytic reactor of claim 13, wherein the non-product materials include combustible substances that combust in the burner.

15. 1. A method for converting reactants into products, comprising: passing the reactants through a heat exchanger to provide heated reactants at a temperature of from 225°C to 725°C; providing a heated reactant to an endothermic catalytic reactor, the endothermic catalytic reactor comprising: a radiant furnace including a burner that provides thermal energy to the furnace; a reactor having an inlet portion and an outlet portion, the reactor being positioned within the furnace and configured to receive radiant heat energy from the furnace; a defined flow path extending through the reactor from the inlet portion to the outlet portion, forming one or more helical spirals, the flow path not being positioned to impede the flow of reactants or starting materials; one or more inlet ports located in the inlet portion for receiving the reactants; an outlet port above the outlet section for discharging product from the reactor; Equipped with The reactor comprises: allowing the reactants to receive radiant heat energy and interact with a catalyst sufficiently to cause a reaction that converts the reactants into products; separating the product from non-product materials; A method comprising:

16. The method of claim 15 , wherein the defined pathways retain a catalyst on an exterior surface of the defined pathways.

17. 16. The method of claim 15, wherein the reactor does not include a catalyst bed along the defined path.

18. 18. The method of claim 17, wherein the reactant is a gas and the reactant flows along the defined path such that the reactant has a Reynolds number between 1,000,000 and 15,000,000.

19. 18. The method of claim 17, wherein the reactant is a gas and flows along the defined path such that the reactant has a Nusselt number between 3,000 and 15,000.

20. 16. The method of claim 15, wherein the reactants have a mass flow rate through the reactor of from 20 kg / sec to 150 kg / sec.

21. 1. A method for producing styrene, comprising: passing a reactant stream comprising ethylbenzene through a heat exchanger to provide a heated reactant stream at a temperature of from 450°C to 725°C; providing the heated reactant stream to an endothermic catalytic reactor, said endothermic catalytic reactor comprising: a radiant furnace including a burner that provides thermal energy to the furnace; a reactor having an inlet portion and an outlet portion, the reactor being positioned within the furnace and configured to receive radiant heat energy from the furnace; a defined flow path extending through the reactor from the inlet portion to the outlet portion to form one or more helical spirals, the flow path being unobstructed by the flow of reactants or starting materials; one or more inlet ports located in the inlet section for receiving the heated reactant stream; an outlet port above the outlet section for discharging a product stream comprising styrene from the reactor; Equipped with the reactor allows the heated reactant stream to receive radiant heat energy and interact with a catalyst sufficiently to cause a reaction that converts ethylbenzene to styrene and by-product hydrogen; the product stream comprising styrene and hydrogen; separating said product stream into a predominantly aqueous phase, a predominantly organic phase, and a non-condensable overhead comprising hydrogen; separating styrene from said primarily organic phase; A method comprising:

22. 22. The method of claim 21, wherein the defined pathways retain a catalyst on an exterior surface thereof.

23. 22. The method of claim 21 , wherein the product stream further comprises unreacted benzene.

24. 22. The method of claim 21, further comprising separating styrene from the aqueous phase.

25. 23. The method of claim 22, wherein the reactor does not include a catalyst bed along the defined path.

26. 23. The method of claim 22, wherein the starting material is a gas and flows along the defined path such that the Reynolds number of the starting material is between 1,000,000 and 15,000,000 and the Nusselt number of the starting material is between 3,000 and 15,000.

27. 23. The method of claim 22, wherein the conversion of ethylbenzene to styrene is at least 70%.

28. 23. The method of claim 22, wherein the styrene is separated from the product stream.

29. Styrene produced by the method of any one of claims 21 to 28.

Images