Process and apparatus for separating hydrogen from hydrocarbons

Abstract

A process and apparatus for providing a high purity hydrogen stream by removing hydrocarbons using a thermal swing adsorption process. An adsorbent is used to remove the hydrocarbons and provide a product stream that is a hydrogen-rich stream. A portion of the product stream is heated and used as a purge stream to desorb the hydrocarbons from the adsorbent. A contaminated stream containing hydrogen and hydrocarbons is cooled and separated into a gas stream and a liquid stream. The vapor stream is mixed with the feed stream. A blower may be used with the vapor stream.

Description

[Technical Field]

[0001] (Priority statement) This application claims the benefit of and priority to U.S. Patent Application No. 18 / 056,747, filed November 18, 2022, which is incorporated herein by reference in its entirety.

[0002] FIELD OF THE INVENTION The present invention relates generally to a process and apparatus for separating hydrogen from hydrocarbons, and more particularly to a process and apparatus that uses a hot portion of a hydrogen product stream as a purge stream. [Background technology]

[0003] Hydrogen from sunlight, wind, and water (green hydrogen) can meet the expected future global energy demand and play an important role in reducing global warming. The recent renewed interest in alternative energy sources and energy carriers opens new perspectives for this process to be applied as a supply system for fuel cells, power generation, and many more applications.

[0004] The reversible dehydrogenation of methylcyclohexane (MCH) to produce toluene (TOL) and hydrogen (via the so-called MTH cycle) has been proposed as a solution for the storage, transportation, and distribution of hydrogen produced from renewable energy sources. For power generation, the hydrogen from this process is typically compressed for downstream power generation units, which typically have very stringent purity requirements (BTX < 1 ppm). Due to the relatively high costs associated with producing green hydrogen, it is necessary to recover almost all of the hydrogen.

[0005] Pressure swing adsorption (PSA) can be a viable option for separating hydrogen using traditional adsorbents such as activated alumina, silica gel, carbon, and zeolites. However, void losses from PSA processes are typically significant, necessitating a recycle scheme to minimize losses. Typically, to maintain a recovery rate of 98+%, more than 95% of the tail gas must be recycled back into the PSA feed. This recycle makes the overall economics of purifying hydrogen from such processes unattractive.

[0006] Therefore, it is desirable to have a more effective and efficient method for purifying hydrogen, especially hydrogen produced from renewable resources. Summary of the Invention

[0007] One or more processes and apparatus have been invented for purifying hydrogen streams using a temperature swing adsorption (TSA) process. Utilizing TSA to provide a high-purity hydrogen stream has great potential for maintaining high recovery rates (98+%) without the need for any compressor compression. The TSA utilized in this invention is a closed-loop regeneration scheme that uses a portion of the high-purity, high-pressure hydrogen product stream as a purge stream. This reduces hydrogen losses and ensures a high-purity product.

[0008] Thus, in at least one aspect, the present invention may be characterized as providing a process for separating hydrogen from hydrocarbons by passing a feed stream comprising hydrogen and hydrocarbons to an adsorption zone; separating the hydrogen from the hydrocarbons in the adsorption zone by selectively adsorbing the hydrocarbons to provide a hydrogen-enriched product stream; heating a portion of the hydrogen-enriched product stream as a purge stream; desorbing the hydrocarbons in the purge stream to provide a contaminated stream; and separating the contaminated stream into a hydrogen stream and a hydrocarbon stream in a separation zone.

[0009] Both adsorption and desorption may be carried out at substantially the same pressure.

[0010] The process may further include combining the hydrogen stream with the feed stream. The separation zone may include a cooler and a separation vessel. The separation vessel may be configured to provide a liquid hydrocarbon stream. A blower may be used to combine the hydrogen stream with the feed stream.

[0011] The adsorption zone may comprise one or more packed beds containing an adsorbent selected from the group consisting of silica gel, alumina, zeolite, activated carbon, MOF, or combinations thereof.

[0012] The adsorption zone may include multiple vessels, each containing a packed bed having an adsorbent, and a first vessel may selectively adsorb the hydrocarbons to separate hydrogen from the hydrocarbons in the adsorption zone to provide a hydrogen-enriched product stream, while a second vessel may transfer a purge stream to the adsorption zone to desorb the hydrocarbons and provide a contaminated stream.

[0013] In a second aspect, the invention may be generally characterized as providing a temperature swing adsorption process for recovering hydrogen from a stream comprising hydrogen and hydrocarbons by adsorbing hydrocarbons from a feed stream containing hydrogen and hydrocarbons with an adsorbent at a predetermined pressure and temperature to produce a hydrogen-enriched product stream; heating a portion of the product stream as a purge stream; desorbing the hydrocarbons from the adsorbent using the purge stream to produce a contaminated stream comprising hydrogen and hydrocarbons at substantially the same pressure as the predetermined pressure of the adsorption step; and separating the contaminated stream into a liquid stream comprising hydrocarbons and a vapor stream comprising hydrogen.

[0014] The process may further include combining the steam stream with the feed stream. The combining step may utilize a blower.

[0015] The adsorbent may be selected from the group consisting of silica gel, alumina, zeolite, activated carbon, MOF, or a combination thereof.

[0016] The process may include cooling the contaminated stream prior to the separation step.

[0017] While the desorption step is taking place in the second vessel, an adsorption step may be simultaneously taking place in the first vessel.

[0018] In a third aspect, the invention can be broadly characterized as providing an apparatus for separating hydrogen from hydrocarbons, comprising: an adsorption zone having a first vessel configured to receive a feed stream comprising hydrogen and hydrocarbons, the first vessel having an adsorbent configured to selectively adsorb hydrocarbons, the first vessel configured to provide a hydrogen-enriched product stream; a heater configured to receive a portion of the hydrogen-enriched product stream and to provide a purge stream; a line configured to transfer the purge stream from the heater to the first vessel for desorbing hydrocarbons using the purge stream to provide a contaminated stream; and a separation zone having a vessel configured to separate the contaminated stream into a hydrogen stream and a hydrocarbon stream.

[0019] The apparatus may further include a line configured to combine the hydrogen stream with the feed stream. The line may include a blower configured to combine the hydrogen stream with the feed stream.

[0020] The adsorbent may be selected from the group consisting of silica gel, alumina, zeolite, activated carbon, MOF, or a combination thereof.

[0021] The separation zone may further include a cooler configured to cool the contaminated stream.

[0022] The adsorption zone may further include a second vessel configured to receive a feed stream comprising hydrogen and hydrocarbons, the second vessel having an adsorbent configured to selectively adsorb the hydrocarbons to provide a hydrogen-enriched stream.

[0023] Further aspects, embodiments and details of the invention, all of which may be combined in any manner, are set out in the detailed description of the invention below. [Brief explanation of the drawings]

[0024] One or more exemplary embodiments of the invention are described below in conjunction with the following drawing figures. [Figure 1] FIG. 1 is a process flow diagram according to the present invention. [Figure 2] FIG. 2 is another process flow diagram according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0025] As described above, the present invention utilizes the TSA process to purify hydrogen streams. The TSA process relies on the fact that, at low temperatures, gases tend to be adsorbed within the pore structure of a microporous adsorbent material or within the free volume of a polymeric material. As the temperature of the adsorbent is increased, the adsorbed gases are released, i.e., desorbed. By cyclically swinging the temperature of the adsorbent bed between a low temperature for adsorption and a high temperature for desorption, the TSA process can be used to separate gases in a mixture when used with an adsorbent that is selective for one or more of the components in the gas mixture being removed.

[0026] In other words, the present invention comprises a TSA process for recovering hydrogen-containing hydrocarbons by adsorbing a feed stream containing hydrogen at a concentration greater than 98 mole percent at a predetermined pressure and temperature by transferring the hydrocarbons to a packed bed containing an adsorbent, such as silica gel, alumina, zeolite, activated carbon, MOF, or a combination thereof, to produce a hydrogen-enriched product stream. A portion of the product stream is heated as a purge stream, and the hot purge stream is passed through the adsorption bed to remove impurities and produce a contaminated stream at the same or substantially the same pressure as the adsorption step. The contaminated stream is passed through a separator to reject the hydrocarbons as a liquid stream and produce a vapor stream containing similar or less hydrogen than the feed stream. The vapor stream and the feed stream can be mixed using a blower.

[0027] With these general principles in mind, one or more embodiments of the invention are described below with the understanding that the description is not intended to be limiting.

[0028] As shown in Figures 1 and 2, an apparatus 10 for separating hydrogen from hydrocarbons includes an adsorption zone 12 having one or more adsorption vessels, or beds, 14a, 14b. Typically, more than one adsorption vessel 14a, 14b is utilized, with at least one adsorption bed producing product and another bed regenerating. In this manner, product gas can be produced continuously.

[0029] An exemplary cycle used for TSA is shown in more detail in Figure 2, which shows the step timeline for one bed, e.g., adsorber vessel 14a, served over the course of a single cycle. Although only adsorber vessel 14a is shown, more than one TSA bed may be in the adsorption or feed step simultaneously.

[0030] In the example shown in Figure 2, the TSA process uses two beds, with the first bed going through each step of the TSA cycle in sequence and the second bed going through each step of the TSA cycle in the same sequence, but the timing of the two beds is configured so that the start and end of the two beds alternate. The cycle schedule is also tabulated below in Table 1.

[0031] [Table 1]

[0032] In the schedule, each row of the grid represents all the different cycle steps a given bed undergoes throughout the cycle, while the columns of the grid represent which cycle steps are being performed by which bed at a particular unit time step. The total cycle time is the sum of all of the individual unit time steps in a particular row. A cycle includes a feed or adsorption step (divided into steps F1, F2, and F3 to show how the feed or adsorption step matches up with the other steps), a heating step (heat), a cooling step (cool), a repressurization step (RP), and an idle step (IDLE).

[0033] Once the adsorption bed is pressurized with the product hydrogen stream to the highest pressure level of the cycle and the target temperature within the bed has stabilized (typically within 5°C of design), a cooled feed stream is introduced into the inlet end of the bed and a pure unadsorbed hydrogen stream containing hydrogen is discharged from the outlet end of the bed. The feed or adsorption step is continued until the mass transfer zone (MTZ) of the preferentially adsorbed component is reached at the outlet end of the bed without substantially breaching the bed.

[0034] At the end of the feed step, the bed is heated with a product hydrogen stream. During the heating step, an effluent containing one or more impurities is removed. Following the heating step, the bed is cooled and repressurized to the feed pressure level with a product hydrogen stream to begin and repeat the cycle.

[0035] The adsorption vessels 14a, 14b may contain a single adsorbent or multiple adsorbents to selectively adsorb hydrocarbons. One skilled in the art can select a suitable adsorbent or adsorbents. The adsorbent may include silica gel, alumina, zeolite, activated carbon, MOFs, or combinations thereof. The adsorption vessels 14a, 14b are configured to receive a feed stream 16 containing hydrogen and hydrocarbons and to provide a hydrogen-enriched product stream 18 having a higher hydrogen concentration compared to the feed stream 16.

[0036] A heater 20 is provided to receive and heat a portion 18a of the hydrogen-enriched product stream 18 to provide a hot purge stream 22. The purge stream 22 is transferred via a line from the heater 20 to one of the adsorption vessels 14a, 14b. In FIG. 2, the adsorption vessel 14a is depicted as receiving the purge stream 22. It should be understood that this is merely illustrative of the manner in which the adsorption vessels 14a, 14b cycle through various stages of a TSA process. An exemplary TSA process is described in U.S. Pat. No. 11,097,219.

[0037] The purge stream 22 heats the adsorbent, resulting in desorption of hydrocarbons from the adsorbent. The adsorption vessels 14a, 14b receiving the purge stream 22 provide a contaminated stream 24 containing desorbed hydrocarbons and hydrogen.

[0038] The apparatus 10 also includes a separation zone 26 having a separation vessel 28 configured to separate the contaminated stream 24 into a gaseous stream 30 containing primarily hydrogen and a liquid stream 32 containing desorbed hydrocarbons. A cooler 34 may be provided to cool the contaminated stream 24 to facilitate separation of the hydrogen and hydrocarbons. The gaseous stream 30 is combined with the feed stream 16. A blower 36 may be utilized in the line combining the gaseous stream 30 with the feed stream 16.

[0039] As is known, adsorption zone 12 typically includes multiple adsorption vessels 14a, 14b, some of which adsorb hydrocarbons to provide product stream 18, and some of which receive purge stream 22 and desorb hydrocarbons. Both the adsorption and desorption steps are conducted at substantially the same pressure, where "substantially the same" means that the pressures are within 10%, or 5%, or 2% of each other.

[0040] experiment In a simulated process, the separation of hydrocarbons from a feed stream containing 98.97% hydrogen and traces of C1-C6 hydrocarbons was analyzed using a TSA and blower according to the present invention, and showed that 99.9% hydrogen recovery was possible. A simulation of the separation using a PSA with a compressor showed slightly lower recovery (99.5%), but the PSA allowed for a larger bed volume (78 m). 3 Compared to 270m 3 ) and required significantly more power (825 KW vs. 250 KW). Thus, the present invention provides a more efficient and effective method for obtaining a high purity hydrogen stream. Thus, the present invention allows for the utilization of TSA separation processes while minimizing hydrogen loss.

[0041] Those skilled in the art should appreciate and understand that various other components, such as valves, pumps, filters, coolers, etc., are not shown in the drawings because their details are well within the knowledge of those skilled in the art and their description is not necessary to practice or understand embodiments of the present invention.

[0042] Any of the above lines, conduits, units, devices, vessels, ambient environments, zones, or the like may be equipped with one or more monitoring components, including sensors, measurement devices, data acquisition devices, or data transmission devices. Signals, process or condition measurements, and data from the monitoring components may be used to monitor conditions in, around, and on the process equipment. Signals, measurements, and / or data generated or recorded by the monitoring components may be collected, processed, and / or transmitted over one or more networks or connections, which may be private or public, general or specific, direct or indirect, wired or wireless, encrypted or unencrypted, and / or combinations thereof. This specification is not intended to be limiting in this respect.

[0043] Signals, measurements, and / or data generated or recorded by the monitoring components may be transmitted to one or more computing devices or systems. The computing devices or systems may include at least one processor and memory storing computer-readable instructions that, when executed by the at least one processor, cause the one or more computing devices to perform a process, which may include one or more steps. For example, the one or more computing devices may be configured to receive data related to at least one piece of equipment associated with the process from one or more monitoring components. The one or more computing devices or systems may be configured to analyze the data. Based on the analysis of the data, the one or more computing devices or systems may be configured to determine one or more recommended adjustments to one or more parameters of one or more processes described herein. The one or more computing devices or systems may be configured to transmit encrypted or unencrypted data including one or more recommended adjustments to one or more parameters of one or more processes described herein.

[0044] Specific Embodiments While the following will be described in conjunction with specific embodiments, it will be understood that this description is illustrative, but not intended to limit the scope of the preceding description and appended claims.

[0045] A first embodiment of the present invention is a process for separating hydrogen from hydrocarbons, the process comprising: passing a feed stream comprising hydrogen and hydrocarbons to an adsorption zone; separating hydrogen from the hydrocarbons in the adsorption zone by selectively adsorbing the hydrocarbons to provide a hydrogen-enriched product stream; heating a portion of the hydrogen-enriched product stream as a purge stream; desorbing the hydrocarbons with the purge stream to provide a contaminated stream; and separating the contaminated stream into a hydrogen stream and a hydrocarbon stream in a separation zone. An embodiment of the present invention is one, any, or all of the preceding embodiments in this paragraph through the first embodiment of this paragraph, wherein both adsorption and desorption occur at substantially the same pressure. An embodiment of the present invention is one, any, or all of the preceding embodiments in this paragraph through the first embodiment of this paragraph, further comprising combining a hydrogen stream with the feed stream. An embodiment of the present invention is one, any, or all of the preceding embodiments in this paragraph through the first embodiment of this paragraph, wherein the separation zone comprises a cooler and a separation vessel, the separation vessel configured to provide a liquid hydrocarbon stream. An embodiment of the invention is one, any, or all of the preceding embodiments of this paragraph through the first embodiment of this paragraph, in which a blower is used to combine the hydrogen stream with the feed stream. An embodiment of the invention is one, any, or all of the preceding embodiments of this paragraph through the first embodiment of this paragraph, in which the adsorption zone comprises one or more packed beds containing an adsorbent selected from the group consisting of silica gel, alumina, zeolite, activated carbon, MOF, or combinations thereof. An embodiment of the invention is one, any, or all of the preceding embodiments of this paragraph through the first embodiment of this paragraph, in which the adsorption zone comprises a plurality of vessels, each containing a packed bed having an adsorbent. An embodiment of the invention is one, any, or all of the preceding embodiments of this paragraph through the first embodiment of this paragraph, in which a first vessel separates hydrogen from hydrocarbons in the adsorption zone by selectively adsorbing the hydrocarbons to provide a hydrogen-rich product stream, while a second vessel moves a purge stream to the adsorption zone to desorb the hydrocarbons and provide a contaminated stream.

[0046] A temperature swing adsorption process for recovering hydrogen from a stream comprising hydrogen and hydrocarbons, comprising: adsorbing hydrocarbons from a feed stream containing hydrogen and hydrocarbons with an adsorbent at a predetermined pressure and temperature to produce a hydrogen-enriched product stream; heating a portion of the product stream as a purge stream; desorbing the hydrocarbons from the adsorbent using the purge stream to produce a contaminated stream comprising hydrogen and hydrocarbons at substantially the same pressure as the predetermined pressure of the adsorption step; and separating the contaminated stream into a liquid stream comprising hydrocarbons and a vapor stream comprising hydrogen. An embodiment of the invention is one, any, or all of the preceding embodiments in this paragraph through the first embodiment of this paragraph, further comprising combining the vapor stream with the feed stream. An embodiment of the invention is one, any, or all of the preceding embodiments in this paragraph through the first embodiment of this paragraph, wherein a blower is utilized for the combining step. An embodiment of the invention is one, any, or all of the preceding embodiments in this paragraph through the first embodiment of this paragraph, wherein the adsorbent is selected from the group consisting of silica gel, alumina, zeolite, activated carbon, MOF, or a combination thereof. An embodiment of the invention is one, any, or all of the preceding embodiments of this paragraph through the first embodiment of this paragraph, further comprising the step of cooling the contaminated stream prior to the separation step.An embodiment of the invention is one, any, or all of the preceding embodiments of this paragraph through the first embodiment of this paragraph, wherein the adsorption step is carried out simultaneously in the first vessel while the desorption step is carried out in the second vessel.

[0047] A second embodiment of the present invention is a temperature swing adsorption process for recovering hydrogen from a stream comprising hydrogen and hydrocarbons, the process comprising: adsorbing hydrocarbons from a feed stream containing hydrogen and hydrocarbons with an adsorbent at a predetermined pressure and temperature to produce a hydrogen-enriched product stream; heating a portion of the product stream as a purge stream; desorbing the hydrocarbons from the adsorbent using the purge stream to produce a contaminated stream comprising hydrogen and hydrocarbons at substantially the same pressure as the predetermined pressure of the adsorption step; and separating the contaminated stream into a liquid stream comprising hydrocarbons and a vapor stream comprising hydrogen. An embodiment of the present invention is one, any, or all of the preceding embodiments in this paragraph through the second embodiment of this paragraph, further comprising combining the vapor stream with the feed stream. An embodiment of the present invention is one, any, or all of the preceding embodiments in this paragraph through the second embodiment of this paragraph, further comprising combining the vapor stream with the feed stream. An embodiment of the invention is one, any, or all of the preceding embodiments of this paragraph through the second embodiment of this paragraph, wherein the adsorbent is selected from the group consisting of silica gel, alumina, zeolite, activated carbon, MOF, or combinations thereof. An embodiment of the invention is one, any, or all of the preceding embodiments of this paragraph through the second embodiment of this paragraph, further comprising a step of cooling the contaminated stream prior to the separation step. An embodiment of the invention is one, any, or all of the preceding embodiments of this paragraph through the second embodiment of this paragraph, wherein an adsorption step is carried out simultaneously in the first vessel while a desorption step is carried out in the second vessel.

[0048] A third embodiment of the present invention is an apparatus for separating hydrogen from hydrocarbons, the apparatus comprising: an adsorption zone having a first vessel configured to receive a feed stream comprising hydrogen and hydrocarbons, the first vessel containing an adsorbent configured to selectively adsorb hydrocarbons, the first vessel configured to provide a hydrogen-enriched product stream; a heater configured to receive a portion of the hydrogen-enriched product stream and provide a purge stream; a line configured to transfer the purge stream from the heater to the first vessel to desorb the hydrocarbons with the purge stream and provide a contaminated stream; and a separation zone having a vessel configured to separate the contaminated stream into a hydrogen stream and a hydrocarbon stream. An embodiment of the present invention is one, any, or all of the preceding embodiments in this paragraph through the third embodiment of this paragraph, further comprising a line configured to combine the hydrogen stream with the feed stream. An embodiment of the present invention is one, any, or all of the preceding embodiments in this paragraph through the third embodiment of this paragraph, further comprising a blower in the line configured to combine the hydrogen stream with the feed stream. An embodiment of the present invention is one, any, or all of the preceding embodiments in this paragraph through the third embodiment of this paragraph, wherein the adsorbent is selected from the group consisting of silica gel, alumina, zeolite, activated carbon, MOF, or combinations thereof. An embodiment of the present invention is one, any, or all of the preceding embodiments in this paragraph through the third embodiment of this paragraph, wherein the separation zone further comprises a cooler configured to cool the contaminated stream. An embodiment of the present invention is one, any, or all of the preceding embodiments in this paragraph through the third embodiment of this paragraph, wherein the adsorption zone further comprises a second vessel configured to receive a feed stream comprising hydrogen and hydrocarbons, the second vessel comprising an adsorbent configured to selectively adsorb the hydrocarbons and provide a hydrogen-enriched stream. Without further elaboration, it is believed that one skilled in the art can, using the preceding description, utilize the present invention to its fullest extent and easily ascertain the essential characteristics of the present invention without departing from the spirit and scope of the present invention, and can make various changes and modifications of the present invention to adapt it to various uses and conditions.The preceding preferred specific embodiments are, therefore, to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way, and are intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.

[0049] Above, all temperatures are set forth in degrees Celsius and all parts and percentages are by weight unless otherwise indicated.

[0050] While at least one exemplary embodiment has been presented in the foregoing detailed description of the present invention, it should be understood that numerous variations exist. It should also be understood that the exemplary embodiment(s) are merely examples and are in no way intended to limit the scope, applicability, or configuration of the present invention. Rather, the foregoing detailed description provides those skilled in the art with a convenient guide for implementing exemplary embodiments of the present invention, and it should be understood that various changes can be made in the functions and arrangement of elements described in the exemplary embodiment without departing from the scope of the present invention as set forth in the appended claims and their legal equivalents.

Claims

1. 1. A process for separating hydrogen from hydrocarbons, comprising: transferring a feed stream (16) comprising hydrogen and hydrocarbons to an adsorption zone (12); separating the hydrogen from the hydrocarbons in the adsorption zone (12) by selectively adsorbing the hydrocarbons to provide a hydrogen-enriched product stream (18); heating a portion (18a) of said hydrogen-enriched product stream (18) as a purge stream (22); desorbing said hydrocarbons in said purge stream (22) to provide a contaminated stream (24); and separating said contaminated stream (24) in a separation zone (26) into a hydrogen stream (30) and a hydrocarbon stream (32).

2. The process of claim 1 , wherein the adsorption and the desorption are both carried out at substantially the same pressure.

3. The process of claim 1, further comprising combining the hydrogen stream (30) with the feed stream (16).

4. The separation zone (26) The process of claim 3, comprising a cooler (34) and a separation vessel (28) configured to provide a liquid hydrocarbon stream (32).

5. 4. The process of claim 3, wherein a blower (36) is used to combine the hydrogen stream (30) with the feed stream (16).

6. 6. The process of any one of claims 1 to 5, wherein the adsorption zone (12) comprises one or more packed beds containing an adsorbent selected from the group consisting of silica gel, alumina, zeolite, activated carbon, MOF, or combinations thereof.

7. 7. The process of claim 6, wherein the adsorption zone (12) comprises a plurality of vessels (14a, 14b), each containing a packed bed having the adsorbent.

8. 8. The process of claim 7, wherein a first vessel (14a) separates the hydrogen from the hydrocarbons in the adsorption zone (12) by selectively adsorbing the hydrocarbons to provide a hydrogen-enriched product stream (18), while a second vessel (14b) transfers the purge stream (14b) to the adsorption zone (12) to desorb the hydrocarbons and provide a contaminated stream (24).

9. 1. An apparatus for separating hydrogen from hydrocarbons, comprising: an adsorption zone (12) comprising a first vessel (14a) configured to receive a feed stream (16) comprising hydrogen and hydrocarbons, said first vessel (14a) containing an adsorbent configured to selectively adsorb said hydrocarbons, said first vessel (14a) configured to provide a hydrogen-enriched product stream (18); a heater (20) configured to receive a portion (18a) of the hydrogen-enriched product stream (18) and to provide a purge stream (22); a line configured to transfer the purge stream (22) from the heater (20) to the first vessel (14a) to desorb the hydrocarbons in the purge stream (22) and provide a contaminated stream (24); a separation zone (26) having a vessel (28) configured to separate the contaminated stream (24) into a hydrogen stream (30) and a hydrocarbon stream (32).

10. 10. The apparatus of claim 9, further comprising a line configured to combine the hydrogen stream with the feed stream, and optionally a blower in the line configured to combine the hydrogen stream with the feed stream.

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