REDUCTION OF ACID CONDENSATION CATALYST COKE YIELD BY SELECTIVE VAPORIZATION OF THE HYDRODEOXYGENATION HEAVIES STREAM

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority to U.S. Provisional Application No. 63/662,829, filed Jun. 21, 2024, the entire contents of which is incorporated by reference herein.

BACKGROUND

Significant amount of attention has been placed on developing new technologies for more efficient energy production. Bioreforming processes can produce aromatic hydrocarbons and other useful compounds from biomass feedstocks, including cellulose, hemicellulose, and lignin. For instance, cellulose and hemicellulose can be used as feedstock for various bioreforming processes, including aqueous phase reforming (APR) and hydrodeoxygenation (HDO)—catalytic reforming processes that, when integrated with hydrogenation, can convert cellulose and hemicellulose into an array of products, including hydrogen, liquid fuels, aromatics, kerosene, diesel fuel, lubricants, and fuel oils, among others. In addition, catalytic acid condensation (AC) can be used to convert oxygenates (e.g., generated by HDO) or other compounds into hydrocarbons.

APR and HDO methods and techniques are described in U.S. Pat. Nos. 6,699,457; 6,964,757; 6,964,758; and 7,618,612 (all to Cortright et al., entitled “Low-Temperature Hydrogen Production from Oxygenated Hydrocarbons”); U.S. Pat. No. 6,953,873 (to Cortright et al., entitled “Low-Temperature Hydrocarbon Production from Oxygenated Hydrocarbons”); and U.S. Pat. Nos. 7,767,867; 7,989,664; and 8,198,486 (all to Cortright, entitled “Methods and Systems for Generating Polyols”), all of which are incorporated herein by reference. Various other APR and HDO methods and techniques are also described in U.S. Pat. Nos. 8,053,615; 8,017,818; 7,977,517; 8,362,307; 8,367,882; and 8,455,705 (all to Cortright and Blommel, entitled “Synthesis of Liquid Fuels and Chemicals from Oxygenated Hydrocarbons”); U.S. Pat. No. 8,231,857 (to Cortright, and entitled “Catalysts and Methods for Reforming Oxygenated Compounds”); U.S. Pat. No. 8,350,108 (to Cortright et al., entitled “Synthesis of Liquid Fuels from Biomass”); and International Patent Application No. PCT/US2008/056330 (to Cortright and Blommel, entitled “Synthesis of Liquid Fuels and Chemicals from Oxygenated Hydrocarbons” and published as WO2008109877A1), all of which are incorporated herein by reference.

It is well established that coking leads to the deactivation of acid condensation catalysts. This phenomenon is a ubiquitous problem in the modern petrochemical and energy transformation industries. The acid condensation catalyst gradually accumulates deposits of coke as the reaction proceeds. The activity of the catalyst gradually declines due to the buildup of coke. Coke formation is believed to result from the deposition of coke precursors including high molecular weight materials and condensed ring aromatic molecules on the catalyst, these polymerizing to form coke. Eventually, economics dictates the necessity of reactivating the catalyst. Consequently, in all processes of this type, the catalyst must necessarily be periodically regenerated. Regeneration often requires time-consuming, costly steps that may remove the catalytic system from operation.

Accordingly, there is a need for methods and systems for reducing coke yield to prolong the activity of catalysts.

SUMMARY OF THE INVENTION

Some aspects of the present disclosure provide a method of producing a C₄₊ compound, including the steps of: (i) reacting an aqueous feed stream comprising an oxygenated hydrocarbon with hydrogen in the presence of a hydrodeoxygenation (HDO) catalyst to produce an HDO product stream; (ii) vaporizing the HDO product stream in a vaporizer to produce a gaseous HDO product stream comprising C₁₊O_1-3 hydrocarbons; and (iii) reacting the gaseous HDO product stream in the presence of an acid condensation (AC) catalyst at a condensation temperature and condensation pressure to produce an AC product stream comprising the C₄₊ compound.

The HDO product stream can be introduced to a packed bed in an upper section of the vaporizer.

At least a first portion of the AC product stream can be recycled to the vaporizer and contacted with the HDO product stream, such that the gaseous HDO product stream is produced from vaporizing the HDO heavy stream and the recycled AC product stream. In some embodiments, at least a second portion of the AC product stream is recycled to the gaseous HDO product stream.

The AC product stream recycled to the vaporizer can be a gas. The temperature of the gaseous AC product stream entering the vaporizer has an inlet temperature of at least 160° C. The AC product stream recycled to the vaporizer can enter the vaporizer at a location below the packed bed to which the HDO heavy stream is introduced.

Step (ii) can further comprise introducing a superheated high-pressure steam to the vaporizer. For example, the superheated high-pressure steam can enter the vaporizer at a location below the AC product stream recycled to the vaporizer.

The HDO product stream can be preheated before entering the vaporizer.

The ratio of the feed rate of the AC product stream recycled to the vaporizer to the feed rate of the HDO product stream can be about 0.5:1 to about 10:1.

The vaporizer can be operated at a temperature of at about 150° C. to about 300° C.

Some aspects of the present disclosure provide a system for producing a C₄₊ compound, the system including (i) an hydrodeoxygenation (HDO) reactor, in which an aqueous feed stream comprising an oxygenated hydrocarbon reacts with hydrogen in the presence of an HDO catalyst to produce an HDO product stream; (ii) a vaporizer, in which the HDO product stream is vaporized to produce a gaseous HDO product stream comprising C₁₊O_1-3 hydrocarbons; and (iii) an acid condensation (AC) reactor, in which the gaseous HDO product stream reacts in the presence of an AC catalyst at a condensation temperature and condensation pressure to produce an AC product stream comprising the C₄₊ compound.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a schematic illustration of a system in accordance with some embodiments of the present disclosure.

FIG. 2 shows a graphical representation of the percentage of overhead splits versus vaporizer bottoms temperature given in Table 1.

FIG. 3 shows contaminant levels in the feed, overheads and bottoms of sample 3 from the vaporization tests.

FIG. 4 shows incremental coke yield (percentage of sample turning to coke) for each sample in Table 2.

FIG. 5 shows C₅₊ product yield as a percentage of carbon in the sugar feed of the first run of the integrated selective vaporizer. Legend: “No” refers to no purge, “PV” refers to 100% purge from the bottom of the HDO Product Flash Drum, and “SV” refers to the inventive selective vaporizer.

FIG. 6 shows C₅₊ product yield as a percentage of carbon in the sugar feed of the second run of the integrated selective vaporizer. Legend: “No” refers to no purge, “PV” refers to 100% purge from the bottom of the HDO Product Flash Drum, and “SV” refers to the inventive selective vaporizer.

FIG. 7 shows a schematic illustration of a method in accordance with some embodiments of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

The present disclosure relates to processes and systems for acid condensation (AC) reactions, including as can be implemented downstream of HDO reactions. The methods and systems for reducing coke yield to prolong the activity of AC catalysts.

In one aspect, disclosed herein are methods of producing a C₄₊ compound, including (i) reacting an aqueous feed stream including an oxygenated hydrocarbon with hydrogen in the presence of a hydrodeoxygenation (HDO) catalyst to produce an HDO product stream; (ii) vaporizing the HDO product stream in a vaporizer to produce a gaseous HDO product stream including C₁₊O_1-3 hydrocarbons; and (iii) reacting the gaseous HDO product stream in the presence of an acid condensation (AC) catalyst at a condensation temperature and condensation pressure to produce an AC product stream comprising the C₄₊ compound.

In another aspect, disclosed herein are systems for producing a C₄₊ compound, the system including: (i) an hydrodeoxygenation (HDO) reactor, in which an aqueous feed stream including an oxygenated hydrocarbon reacts with hydrogen in the presence of an HDO catalyst to produce an HDO product stream; (ii) a vaporizer, in which the HDO product stream is vaporized to produce a gaseous HDO product stream including C₁₊O_1-3 hydrocarbons; and (iii) an acid condensation (AC) reactor, in which the gaseous HDO product stream reacts in the presence of an AC catalyst at a condensation temperature and condensation pressure to produce an AC product stream including the C₄₊ compound.

Generally, the technology disclosed herein can be used to improve AC processing for a wide range of feed streams. As an example context, FIG. 1 illustrates a system for treatment of HDO products in advance of AC processing, with the relevant HDO reactions being implemented for a feed stream from an upstream hydrogenation reactor system (not shown). A wide variety of systems can be implemented to provide a feed stream to an AC reactor system (e.g., as variously disclosed in U.S. Pat. Nos. 6,699,457; 6,964,757; 6,964,758; 7,618,612; 6,953,873; 7,767,867; 7,989,664; 6,953,873; 7,767,867; 7,989,664; 8,198,486; 8,053,615; 8,017,818; 7,977,517; 8,362,307; 8,367,882; 8,455,705 8,231,857; and 8,350,108; in International Patent Publication WO2008109877A1; or as otherwise known in the art). In some cases, the aqueous feed stream is derived from biomass.

The products of HDO reaction can be fractionated into an HDO light stream and an HDO heavy stream. As used herein, the term “HDO light stream” or “HDO lights” can refer to products deriving from the vapor stream leaving the bottom of a HDO reactor. In practice, a certain portion of vapor products can flash off from the HDO reactor liquid product when the pressure is letdown in a HDO product flash drum, which can be referred to as HDO product flash drum overheads. As used herein, the term “HDO heavy stream” or “HDO heavies” can refer to a remaining liquid phase when the HDO reactor liquid product is let down in pressure from about 125 bara to 20 bara in an adiabatic flash that is carried out in the HDO product flash drum (with a resulting temperature of 230-290° C.). The HDO heavies can include C₆₋ products as main components, including C₂-C₄ diols as well as heavy C₆ components such as 1,4-sorbitan and 2,5-bis(hydroxymethyl)tetrahydrofuran. The term “HDO product stream” can typically refer to the HDO heavy stream as defined herein or an HDO reaction-derived stream fed in to the vaporizer, which comprises at least a portion of the HDO heavy stream. The HDO light stream may be directly fed to downstream AC reaction. The present method can be used to isolate gaseous HDO products from the HDO heavy stream. The isolated gaseous HDO products can then be combined with the HDO light stream and fed to the AC reaction.

For example, referring to FIG. 1, the present method can include: (i) reacting an aqueous feed stream comprising an oxygenated hydrocarbon with hydrogen in the presence of a hydrodeoxygenation (HDO) catalyst to produce an HDO light stream including a first pool of C₁₊O_1-3 hydrocarbons and an HDO heavy stream (4); (ii) vaporizing at least a portion of the HDO heavy stream in a vaporizer to produce a gaseous HDO product stream (6) including a second pool of C₁₊O_1-3 hydrocarbons; and (iii) feeding the HDO light stream and the gaseous HDO product stream to an acid condensation (AC) reactor, thereby reacting the first and second pools of C₁₊O_1-3 hydrocarbons in the presence of an acid condensation catalyst at a condensation temperature and condensation pressure to produce an AC product stream comprising the C₄₊ compound.

As used herein, the term “vaporize” or “vaporization” refers to converting a material to the gas phase or to a vapor (e.g., a mist). Any suitable vaporizer can be used to vaporize the HDO product stream. In some cases, the vaporizer is a selective vaporize. For example, the vaporizer can be a pressure vessel with a bed of packing or multiple beds of packing. The vaporizer may include a bed of packing. In some cases, the bed of packing may be random. In some cases, the bed of packing may be structured. In some cases, the vaporizer has an upper section, a middle section, and a lower section. In some cases, the bed of packing is located in a middle section, an upper section, or a lower section. In some cases, the HDO product stream is introduced to a packed bed in an upper section of the vaporizer. In some cases, the HDO heavy stream is introduced in an upper section of the vaporizer, above a bed of packing. In some cases, the HDO product stream may be introduced to the vaporizer via a liquid distributor. For example, the liquid distributor can be a spray nozzle where the stream is liquid only. In some cases, the HDO product stream is preheated before entering the vaporizer by a preheater (see FIG. 1, structure B). In some cases, the HDO heavy stream is preheated (5) before entering the vaporizer. For example, the stream is heated upstream of the selective vaporizer in a heat exchanger using hot oil. A portion of the stream can be vaporized in the heat exchanger itself such that the feed to the selective vaporizer is a vapor/liquid stream. In such cases, the inlet device can be a 2-phase inlet device (e.g., from a distillation column internals vendor such as Sulzer or Koch-Glitsch). In some cases, the HDO product stream (e.g., the HDO heavy stream) is introduced to the vaporizer at a feed rate. The feed rate of the HDO product stream can vary depending on the capacity of the plant. For lab scale tests, the feed rate can be about 100 g/hr to about 200 g/hr, about 50 g/hr to about 500 g/hr, about 75 g/hr to about 250 g/hr, or about 90 g/hr to about 210 g/hr. On a production scale, the HDO heavy stream feed rate may, in some embodiments, vary from 25 to 60 metric tons per hour. In another aspect, the vaporizer is operated at a temperature of at about 150° C. to about 300° C., such as about 200° C. to about 300° C., about 250° C. to about 300° C., about 250° C. to about 280° C., or about 250° C. to about 275° C. The operating temperature can vary based on the temperature of the AC product stream. In some embodiments, the AC product stream has a temperature of about 300° C. and the vaporizer is operated at a temperature of 280° C. at the start of run (SOR) and 265° C. at the end of run (EOR).

In another aspect, and still referring to FIG. 1, at least a first portion of the AC product stream (1) (e.g., preheated AC recycle gas) can be recycled to the vaporizer and contacted with the HDO heavy stream, such that the gaseous HDO product stream is produced from vaporizing the HDO heavy stream and the recycled AC product stream. Optionally, at least a second portion of the AC product stream is recycled to the gaseous HDO product stream. In some cases, the AC product stream is recycled to the gaseous HDO product stream via a Selective Vaporizer bypass line (2). In some cases, the AC product stream recycled to the vaporizer enters the vaporizer at a location below the packed bed to which the HDO heavy stream is introduced (e.g., the AC product stream is introduced in a middle section of the vaporizer). In some cases, the AC product stream recycled to the vaporizer is a gas. In another aspect, the temperature of the AC product stream entering the vaporizer has an inlet temperature. In some cases, the inlet temperature is at least 100° C., at least 110° C., at least 120° C., at least 130° C., at least 140° C., at least 160° C., at least 170° C., at least 180° C., at least 190° C., at least 200° C., or at least 250° C. In some embodiments, the inlet temperature is about 300° C.

In another aspect, the step of vaporizing at least a portion of the HDO heavy stream in a vaporizer to produce a gaseous HDO product stream (6) including a second pool of C₁₊O_1-3 hydrocarbons may further include introducing a superheated high-pressure steam (3) to the vaporizer. As shown in FIG. 1, the superheated high-pressure steam enters the vaporizer at a location below the AC product stream (e.g., in a lower section of the vaporizer) recycled to the vaporizer. The AC product stream recycled to the vaporizer is introduced to the vaporizer at a feed rate. The feed rate of the AC product stream can vary depending on the capacity of the plant. For lab scale tests, the feed rate can be about 100 g/hr to about 1000 g/hr, about 1 g/hr to about 2000 g/hr, about 50 g/hr to about 100 g/hr, about 75 g/hr to about 1200 g/hr, or about 90 g/hr to about 1100 g/hr. On a production scale, the feed rate of the AC product stream recycled to the vaporizer heavy stream may, in some embodiments, vary from 200 to 260 metric tons per hour.

In another aspect, the feed rate of the AC product stream to the vaporizer and the feed rate of the HDO heavy stream to the vaporizer may be in a ratio. In some cases, the feed rate of the AC product stream and the feed rate of the HDO heavy stream is about 0.2:1 to about 100:1, about 0.5:1 to about 100:1, about 0.5:1 to about 50:1, about 0.5:1 to about 10:1; about 1:1 to about 50:1, about 2:1 to about 50:1, about 4:1 to about 20:1; about 4:1 to about 15:1, or about 4:1 to about 10:1. For example, the feed rate of the AC product stream and the feed rate of the HDO heavy stream can be about 4:8:1 at the start of run (SOR) to about 7.4:1 at the end of run (EOR).

Referring to FIG. 7, disclosed herein is a method including (i) reacting an aqueous feed stream including an oxygenated hydrocarbon with hydrogen in the presence of a hydrodeoxygenation (HDO) catalyst to produce an HDO product stream (700); (ii) vaporizing the HDO product stream in a vaporizer to produce a gaseous HDO product stream including C₁₊O_1-3 hydrocarbons (701); and (iii) reacting the gaseous HDO product stream in the presence of an acid condensation (AC) catalyst at a condensation temperature and condensation pressure to produce an AC product stream comprising the C₄₊ compound (702). In some cases, step (ii, 701) further includes introducing a superheated high-pressure steam to the vaporizer (704). In some cases, at least a first portion of the AC product stream is recycled to the vaporizer and contacted with the HDO product stream (705), such that the gaseous HDO product stream is produced from vaporizing the HDO heavy stream and the recycled AC product stream. Optionally, wherein at least a second portion of the AC product stream is recycled to the gaseous HDO product stream (706).

The methods and systems disclosed herein may be carried out or operated batchwise or continuously.

HDO Catalyst and HDO Reaction

The term “hydrodeoxygenation catalyst” (HDO catalyst) refers to a catalyst that catalyzes a process that removes oxygen from oxygen-containing compounds in the presence of hydrogen. Suitable HDO catalysts and processes include, for example, those described in WO 2014/152370 and WO/2023/064565, all of which are incorporated herein by reference.

In some embodiments, the HDO catalyst is composed of a heterogeneous catalyst having one or more materials capable of catalyzing a reaction between hydrogen and a feedstock solution to remove one or more of the oxygen atoms from the feedstock solution to produce one or more oxygenate. In some embodiments, the HDO catalyst is composed of one or more metal adhered to a support and may include, without limitation, Cu, Re, Fe, Ru, Ir, Co, Rh, Pt, Pd, Ni, W, Os, Mo, Ag, Au, alloys and combinations thereof. The HDO catalyst may include these elements alone or in combination with one or more promoters, such as Mn, Cr, Mo, W, V, Nb, Ta, Ti, Zr, Y, La, Sc, Zn, Cd, Ag, Au, Sn, Ge, P, Al, Ga, In, Tl, and combinations thereof. In some embodiments, the HDO catalyst includes Pt, Ru, Cu, Re, Co, Fe, Ni, W or Mo. In some embodiments, the HDO catalyst includes Fe or Re and at least one transition metal selected from Ir, Ni, Pd, P, Rh, and Ru. In some embodiments, the HDO catalyst includes Fe, Re and at least Cu or one Group VIIIB transition metal. In some embodiments, the metal of the HDO catalyst comprises Pd, W, Mo, Ni, Pt, Ru, or a combination thereof. In some embodiments, the HDO catalyst comprises a promoter. As an example, the promoter of the deoxygenation catalyst can comprise Sn, W, or a combination thereof. The support may include a nitride, carbon, silica, alumina, zirconia, titania, vanadia, ceria, zinc oxide, chromia, boron nitride, heteropolyacids, kieselguhr, hydroxyapatite, or a mixture thereof. In some embodiments, the support comprises zirconia.

The aqueous feed stream is reacted with hydrogen in the presence of the HDO catalyst at temperatures, pressures, and weight hourly space velocities effective to produce the desired oxygenate products. The specific oxygenates produced will depend on various factors, including the feedstock solution, reaction temperature, reaction pressure, water concentration, hydrogen concentration, the reactivity of the catalyst, and the flow rate of the feedstock solution as it affects the space velocity (the mass/volume of reactant per unit of catalyst per unit of time), gas hourly space velocity (GHSV), and weight hourly space velocity (WHSV). For example, an increase in flow rate, and thereby a reduction of the feed stream exposure to the HDO catalyst over time, will limit the extent of the reactions that may occur, thereby causing increased yield for higher level di- and tri-oxygenates, with a reduction in ketone, alcohol, and cyclic ether yields.

In general, the reaction may include a temperature gradient to allow partial deoxygenation of the oxygenated hydrocarbon at temperatures below the caramelization point of a feedstock, from which the aqueous feed stream is generated. Including a temperature gradient helps prevent the oxygenated hydrocarbons in the feed stream from condensing (e.g., caramelizing) on the catalyst and creating a substantial pressure drop across the reactor, which can lead to inoperability of the reactor. The caramelization point, and therefore the required temperature gradient, will vary depending on the feedstock. In one embodiment, the temperature gradient is from about 170° C. to 300° C. or between about 200° C. to 290° C. In another embodiment, a temperature gradient is not employed.

Operating pressures up to about 2000 psig can be used to help maintain the carbon backbone, minimize the amount of light organic acids and ketones that are formed, and increasing the product selectivity towards alcohols. By increasing operating pressures, the thermodynamics of the reaction favors alcohols to ketones and organic acids, thereby shifting the product selectivity, maintaining the carbon backbone, and improving product yields. Light organic acids are particularly undesirable products as they are highly corrosive. Producing fewer light organic acids provides more flexibility with regards to materials of construction of a reactor system because corrosion is less of an issue.

The reaction temperature and pressures are preferably selected to maintain at least a portion of a feedstock, from which the aqueous feed stream is generated, in the liquid phase at the reactor inlet. It is recognized, however, that temperature and pressure conditions may also be selected to more favorably produce the desired products in the vapor-phase. In general, the reaction should be conducted at process conditions wherein the thermodynamics of the proposed reaction are favorable. For instance, the minimum pressure required to maintain a portion of the feedstock in the liquid phase will likely vary with the reaction temperature. As temperatures increase, higher pressures will generally be required to maintain the feedstock in the liquid phase, if desired. Pressures above that required to maintain the feedstock in the liquid phase (i.e., vapor-phase) are also suitable operating conditions.

In condensed phase liquid reactions, the pressure within the reactor must be sufficient to maintain the reactants in the condensed liquid phase at the reactor inlet. For liquid phase reactions, the reaction temperature should be greater than about 100° C., or 120° C., or 150° C., or 180° C., or 200° C., and less than about 300° C., or 290° C., or 270° C., or 250° C., or 220° C. The reaction pressure should be greater than about 70 psig, or 145 psig, or 300 psig, or 500 psig, or 750 psig, or 1050 psig, and less than about 2000 psig, or 1950 psig, or 1900 psig, or 1800 psig. In one embodiment, the reaction temperature is between about 120° C. and 300° C., or between about 200° C. and 300° C., or between about 270° C. and 290° C., and the reaction pressure is between about 145 and 1950 psig, or between about 1000 and 1900 psig, or between about 1050 and 1800 psig.

For vapor phase reactions, the reaction should be carried out at a temperature where the vapor pressure of the oxygenated hydrocarbon is at least about 0.1 atm, preferably higher (e.g., 350 psi), and the thermodynamics of the reaction are favorable. This temperature will vary depending upon the specific oxygenated hydrocarbon compound used, but is generally greater than about 100° C., or 120° C., or 250° C., and less than about 600° C., or 500° C., or 400° C. for vapor phase reactions. In one embodiment, the reaction temperature is between about 120° C. and about 500° C., or between about 250° C. and about 400° C.

In general, the HDO reaction should be conducted under conditions where the residence time of the aqueous feed stream over the catalyst is appropriate to generate the desired products. For example, the WHSV for the reaction may be at least 0.01 gram of oxygenated hydrocarbon per gram of catalyst per hour (g/g-hr). In some embodiments, the WHSV for the HDO reaction is 0.01 to about 40.0 g/g-hr, such as about 0.05 to about 40.0, about 1.0 to about 40.0, about 5.0 to about 40.0, or about 1.0 to about 20.0 g/g-hr. The WHSV can be, for example, about 0.05, 0.1, 0.25, 0.5, 0.75, 1.0, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30, 35, or 40 g/g-hr.

In some embodiments, the amount of hydrogen fed to the HDO reaction ranges from 0-2400%, 5-2400%, 10-2400%, 15-2400%, 20-2400%, 25-2400%, 30-2400%, 35-2400%, 40-2400%, 45-2400%, 50-2400%, 55-2400%, 60-2400%, 65-2400%, 70-2400%, 75-2400%, 80-2400%, 85-2400%, 90-2400%, 95-2400%, 98-2400%, 100-2400%, 200-2400%, 300-2400%, 400-2400%, 500-2400%, 600-2400%, 700-2400%, 800-2400%, 900-2400%, 1000-2400%, 1100-2400%, or 1150-2400%, or 1200-2400%, or 1300-2400%, or 1400-2400%, or 1500-2400%, or 1600-2400%, or 1700-2400%, or 1800-2400%, or 1900-2400%, or 2000-2400%, or 2100-2400%, or 2200-2400%, or 2300-2400%, based on the total number of moles of the oxygenated hydrocarbon(s) in the feedstock, including all intervals between. The hydrogen may be external hydrogen or recycled hydrogen. The term “external H₂” refers to hydrogen that does not originate from the feedstock solution but is added to the reactor system from an external source. The term “recycled H₂” refers to unconsumed hydrogen, which is collected and then recycled back into the reactor system for further use.

AC Catalyst and AC Reactions

The methods disclosed herein may reduce the coke yield on fouled acid condensation catalyst. The technology disclosed herein can be used to reduce coke yield on AC catalyst fouled during processing of a wide range of feed streams. As an example context, AC processing of hydrodeoxygenation (HDO) products, with the relevant HDO reactions being implemented for a feed stream from an upstream hydrogenation reactor system (not shown), are considered. A wide variety of systems can be implemented to provide a feed stream to an AC reactor system (e.g., as variously disclosed in U.S. Pat. Nos. 6,699,457; 6,964,757; 6,964,758; 7,618,612; 6,953,873; 7,767,867; 7,989,664; 6,953,873; 7,767,867; 7,989,664; 8,198,486; 8,053,615; 8,017,818; 7,977,517; 8,362,307; 8,367,882; 8,455,705 8,231,857; and 8,350,108; in International Patent Publication WO2008109877A1; or as otherwise known in the art). In some cases, the feed stream is derived from biomass. In some cases, the biomass feedstock includes cellulose, hemicellulose, and lignin. For instance, cellulose and hemicellulose.

In some examples, reacting the HDO product stream (or another product stream) in the presence of a condensation catalyst (i.e., in the AC reactor, D) can produce a C₄₊ compound. The C₄₊ compound can include a member selected from the group consisting of C₄₊ alcohol, C₄₊ ketone, C₄₊ alkane, C₄₊ alkene, C₅₊ cycloalkane, C₅₊ cycloalkene, aryl, fused aryl, and a mixture thereof. In one exemplary embodiment, the C₄₊ alkane comprises a branched or straight chain C_4-30 alkane, or a branched or straight chain C_4-9, C_7-14, C_12-24 alkane, or a mixture thereof. In another exemplary embodiment, the C₄₊ alkene comprises a branched or straight chain C_4-30 alkene, or a branched or straight chain C_4-9, C_7-14, C_12-24 alkene, or a mixture thereof. In another exemplary embodiment, the C₅₊ cycloalkane comprises a mono-substituted or multi-substituted C₅₊ cycloalkane, and at least one substituted group is a branched C₃₊ alkyl, a straight chain C₁₊ alkyl, a branched C₃₊ alkylene, a straight chain C₁₊ alkylene, a phenyl, or a combination thereof, or a branched C_3-12 alkyl, a straight chain C_1-12 alkyl, a branched C_3-12 alkylene, a straight chain C_1-12 alkylene, a phenyl, or a combination thereof, or a branched C_3-4 alkyl, a straight chain C_1-4 alkyl, a branched C_3-4 alkylene, straight chain C_1-4 alkylene, a phenyl, or a combination thereof. In another exemplary embodiment, the C₅₊ cycloalkene comprises a mono-substituted or multi-substituted C₅₊ cycloalkene, and at least one substituted group is a branched C₃₊ alkyl, a straight chain C₁₊ alkyl, a branched C₃₊ alkylene, a straight chain C₂₊ alkylene, a phenyl, or a combination thereof, or a branched C_3-12 alkyl, a straight chain C_1-12 alkyl, a branched C_3-12 alkylene, a straight chain C_2-12 alkylene, a phenyl, or a combination thereof, or a branched C_3-4 alkyl, a straight chain C_1-4 alkyl, a branched C_3-4 alkylene, straight chain C_2-4 alkylene, a phenyl, or a combination thereof. In another exemplary embodiment, the aryl comprises an unsubstituted aryl, or a mono-substituted or multi-substituted aryl, and at least one substituted group is a branched C₃₊ alkyl, a straight chain C₁₊ alkyl, a branched C₃₊ alkylene, a straight chain C₂₊ alkylene, a phenyl, or a combination thereof, or a branched C_3-12 alkyl, a straight chain C_1-12 alkyl, a branched C_3-12 alkylene, a straight chain C_2-12 alkylene, a phenyl, or a combination thereof, or a branched C_3-4 alkyl, a straight chain C_1-4 alkyl, a branched C_3-4 alkylene, a straight chain C_2-4 alkylene, a phenyl, or a combination thereof. In another exemplary embodiment, the fused aryl comprises an unsubstituted fused aryl, or a mono-substituted or multi-substituted fused aryl, and at least one substituted group is a branched C₃₊ alkyl, a straight chain C₁₊ alkyl, a branched C₃₊ alkylene, a straight chain C₂₊ alkylene, a phenyl, or a combination thereof, or a branched C_3-4 alkyl, a straight chain C_1-4 alkyl, a branched C_3-4 alkylene, a straight chain C_2-4 alkylene, a phenyl, or a combination thereof. In another exemplary embodiment, the C₄₊ alcohol comprises a compound according to the formula R¹—OH, wherein R¹ is a branched C₄₊ alkyl, straight chain C₄₊ alkyl, a branched C₄₊ alkylene, a straight chain C₄₊ alkylene, a substituted C₅₊ cycloalkane, an unsubstituted C₅₊ cycloalkane, a substituted C₅₊ cycloalkene, an unsubstituted C₅₊ cycloalkene, an aryl, a phenyl, or a combination thereof.

In another exemplary embodiment of method of making the C₄₊ compound, the C₄₊ ketone comprises a compound according to the formula

wherein R³ and R⁴ are independently a branched C₃₊ alkyl, a straight chain C₁₊ alkyl, a branched C₃₊ alkylene, a straight chain C₂₊ alkylene, a substituted C₅₊ cycloalkane, an unsubstituted C₅₊ cycloalkane, a substituted C₅₊ cycloalkene, an unsubstituted C₅₊ cycloalkene, an aryl, a phenyl, or a combination thereof. Examples of desirable C₄₊ ketones include, without limitation, butanone, pentanone, hexanone, heptanone, octanone, nonanone, decanone, undecanone, dodecanone, tridecanone, tetradecanone, pentadecanone, hexadecanone, heptyldecanone, octyldecanone, nonyldecanone, eicosanone, uneicosanone, doeicosanone, trieicosanone, tetraeicosanone, or isomers thereof.

The condensation catalyst is generally a catalyst capable of forming longer chain compounds by linking two molecules (e.g., oxygen containing species or other functionalized compounds, including olefins) through a new carbon-carbon bond, and converting the resulting compound to a hydrocarbon, alcohol, or ketone. In some embodiments, the condensation catalyst is an acid condensation catalyst. The condensation catalyst may include, without limitation, carbides, nitrides, zirconia, alumina, silica, aluminosilicates, phosphates, zeolites (e.g., ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35 and ZSM-48), titanium oxides, zinc oxides, vanadium oxides, lanthanum oxides, yttrium oxides, scandium oxides, magnesium oxides, cerium oxides, barium oxides, calcium oxides, hydroxides, heteropolyacids, inorganic acids, acid modified resins, base modified resins, and combinations thereof. The condensation catalyst may include the above alone or in combination with a modifier, such as Ce, La, Y, Sc, P, B, Bi, Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, and combinations thereof. The condensation catalyst may also include a metal, such as Cu, Ag, Au, Pt, Ni, Fe, Co, Ru, Zn, Cd, Ga, In, Rh, Pd, Ir, Re, Mn, Cr, Mo, W, Sn, Os, alloys and combinations thereof, to provide a metal functionality.

The condensation catalyst may be self-supporting (i.e., the catalyst does not need another material to serve as a support) or may require a separate support suitable for suspending the catalyst in the reactant stream. One particularly beneficial support is silica, especially silica having a high surface area (greater than 100 square meters per gram), obtained by sol-gel synthesis, precipitation or fuming. In other embodiments, particularly when the condensation catalyst is a powder, the catalyst system may include a binder to assist in forming the catalyst into a desirable catalyst shape. Applicable forming processes include extrusion, pelletization, oil dropping, or other known processes. Zinc oxide, alumina, and a peptizing agent may also be mixed together and extruded to produce a formed material. After drying, this material is calcined at a temperature appropriate for formation of the catalytically active phase, which usually requires temperatures in excess of 450° C.

The condensation catalyst may include one or more zeolite structures comprising cage-like structures of silica-alumina. Zeolites are crystalline microporous materials with well-defined pore structures. Zeolites contain active sites, usually acid sites, which can be generated in the zeolite framework. The strength and concentration of the active sites can be tailored for particular applications. Examples of suitable zeolites for condensing secondary alcohols and alkanes may comprise aluminosilicates, optionally modified with cations, such as Ga, In, Zn, Mo, and mixtures of such cations, as described, for example, in U.S. Pat. No. 3,702,886, which is incorporated herein by reference. As recognized in the art, the structure of the particular zeolite or zeolites may be altered to provide different amounts of various hydrocarbon species in the product mixture. Depending on the structure of the zeolite catalyst, the product mixture may contain various amounts of aromatic and cyclic hydrocarbons.

Examples of suitable zeolite catalysts include ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35 and ZSM-48. Zeolite ZSM-5, and the conventional preparation thereof, is described in U.S. Pat. No. 3,702,886; Re. 29,948 (highly siliceous ZSM-5); U.S. Pat. Nos. 4,100,262 and 4,139,600, all incorporated herein by reference. Zeolite ZSM-11, and the conventional preparation thereof, is described in U.S. Pat. No. 3,709,979, which is also incorporated herein by reference. Zeolite ZSM-12, and the conventional preparation thereof, is described in U.S. Pat. No. 3,832,449, incorporated herein by reference. Zeolite ZSM-23, and the conventional preparation thereof, is described in U.S. Pat. No. 4,076,842, incorporated herein by reference. Zeolite ZSM-35, and the conventional preparation thereof, is described in U.S. Pat. No. 4,016,245, incorporated herein by reference. Another preparation of ZSM-35 is described in U.S. Pat. No. 4,107,195, the disclosure of which is incorporated herein by reference. ZSM-48, and the conventional preparation thereof, is taught by U.S. Pat. No. 4,375,573, incorporated herein by reference. Other examples of zeolite catalysts are described in U.S. Pat. Nos. 5,019,663 and 7,022,888, also incorporated herein by reference. An exemplary condensation catalyst is a ZSM-5 zeolite modified with Cu, Pd, Ag, Pt, Ru, Re, Ni, Sn, or combinations thereof.

As described in U.S. Pat. No. 7,022,888, which is incorporated herein by reference, the condensation catalyst may be a bifunctional pentasil zeolite catalyst including at least one metallic element from the group of Cu, Ag, Au, Pt, Ni, Fe, Co, Ru, Zn, Cd, In, Rh, Pd, Ir, Re, Mn, Cr, Mo, W, Sn, Os, alloys and combinations thereof, or a modifier from the group of In, Zn, Fe, Mo, Au, Ag, Y, Sc, Ni, P, Ta, lanthanides, and combinations thereof. The zeolite may have strong acidic sites, and may be used with reactant streams containing an oxygenated hydrocarbon at a temperature of below 580° C. The bifunctional pentasil zeolite may have ZSM-5, ZSM-8 or ZSM-11 type crystal structure consisting of a large number of 5-membered oxygen-rings (i.e., pentasil rings). In one embodiment the zeolite will have a ZSM-5 type structure.

Alternatively, solid acid catalysts such as alumina modified with phosphates, chloride, silica, and other acidic oxides may be used. Also, sulfated zirconia, phosphated zirconia, titania zirconia, or tungstated zirconia may provide the necessary acidity. Re and Pt/Re catalysts are also useful for promoting condensation of oxygenates to C₅₊ hydrocarbons and/or C₅₊ mono-oxygenates. The Re is sufficiently acidic to promote acid-catalyzed condensation. In certain embodiments, acidity may also be added to activated carbon by the addition of either sulfates or phosphates.

The specific C₄₊ compounds produced will depend on various factors, including, without limitation, the type of oxygenated compounds in the reactant stream, condensation temperature, condensation pressure, the reactivity of the catalyst, and the flow rate of the reactant stream as it affects the space velocity, GHSV, LHSV, and WHSV. In certain embodiments, the reactant stream is contacted with the condensation catalyst at a WHSV that is appropriate to produce the desired hydrocarbon products. In one embodiment the WHSV is at least 0.1 grams of volatile (C₂₊O_1-3) oxygenates in the reactant stream per gram catalyst per hour. In another embodiment the WHSV is between 0.1 to 10.0 g/g hr, including a WHSV of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 g/g hr, and increments between.

In certain embodiments the condensation reaction is carried out at a temperature and pressure at which the thermodynamics of the proposed reaction are favorable. For volatile C₂₊O_1-3 oxygenates the reaction may be carried out at a temperature where the vapor pressure of the volatile oxygenates is at least 0.1 atm (and preferably a good deal higher). The condensation temperature will vary depending upon the specific composition of the oxygenated compounds. The condensation temperature will generally be greater than 80° C., or 100° C., or 125° C., or 150° C., or 175° C., or 200° C., or 225° C., or 250° C., and less than 500° C., or 450° C., or 425° C., or 375° C., or 325° C., or 275° C. For example, the condensation temperature may be between 80° C. to 500° C., or between 125° C. to 450° C., or between 250° C. to 425° C. The condensation pressure will generally be greater than 0 psig, or 10 psig, or 100 psig, or 200 psig, and less than 2000 psig, or 1800 psig or, or 1600 psig, or 1500 psig, or 1400 psig, or 1300 psig, or 1200 psig, or 1100 psig, or 1000 psig, or 900 psig, or 700 psig. For example, the condensation pressure may be greater than 0.1 atm, or between 0 and 1500 psig, or between 0 and 1200 psig.

C₄₊ alkanes and C₄₊ alkenes produced from acid condensation can have from 4 to 30 carbon atoms (C₄₊ alkanes and C₄₊ alkenes) and may be branched or straight chained alkanes or alkenes. The C₄₊ alkanes and C₄₊ alkenes may also include fractions of C_4-9, C_7-14, C_12-24 alkanes and alkenes, respectively, with the C_4-9 fraction directed to gasoline, the C_7-16 fraction directed to jet fuels, and the C_11-24 fraction directed to diesel fuel and other industrial applications, such as chemicals. Examples of various C₄₊ alkanes and C₄₊ alkenes include, without limitation, butane, butene, pentane, pentene, 2-methylbutane, hexane, hexene, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, 2,3-dimethylbutane, heptane, heptene, octane, octene, 2,2,4,-trimethylpentane, 2,3-dimethyl hexane, 2,3,4-trimethylpentane, 2,3-dimethylpentane, nonane, nonene, decane, decene, undecane, undecene, dodecane, dodecene, tridecane, tridecene, tetradecane, tetradecene, pentadecane, pentadecene, hexadecane, hexadecene, heptyldecane, heptyldecene, octyldecane, octyldecene, nonyldecane, nonyldecene, eicosane, eicosene, uneicosane, uneicosene, doeicosane, doeicosene, trieicosane, trieicosene, tetraeicosane, tetraeicosene, and isomers thereof.

C₅₊ cycloalkanes and C₅₊ cycloalkenes produced from acid condensation can have from 5 to 30 carbon atoms and may be unsubstituted, mono-substituted or multi-substituted. In the case of mono-substituted and multi-substituted compounds, the substituted group may include a branched C₃₊ alkyl, a straight chain C₁₊ alkyl, a branched C₃₊ alkylene, a straight chain C₂₊ alkylene, a phenyl or a combination thereof. By way of example, at least one of the substituted groups include a branched C_3-12 alkyl, a straight chain C_1-12 alkyl, a branched C_3-12 alkylene, a straight chain C_1-12 alkylene, a straight chain C_2-12 alkylene, a phenyl or a combination thereof. By way of further example, at least one of the substituted groups include a branched C_3-4 alkyl, a straight chain C_1-4 alkyl, a branched C_1-4 alkylene, straight chain C_1-4 alkylene, straight chain C_2-4 alkylene, a phenyl or a combination thereof. Examples of desirable C₅₊ cycloalkanes and C₅₊ cycloalkenes include, without limitation, cyclopentane, cyclopentene, cyclohexane, cyclohexene, methyl-cyclopentane, methyl-cyclopentene, ethyl-cyclopentane, ethyl-cyclopentene, ethyl-cyclohexane, ethyl-cyclohexene, propyl-cyclohexane, butyl-cyclopentane, butyl-cyclohexane, pentyl-cyclopentane, pentyl-cyclohexane, hexyl-cyclopentane, hexyl-cyclohexane, and isomers thereof.

Aryls will generally consist of an aromatic hydrocarbon in either an unsubstituted (phenyl), mono-substituted or multi-substituted form. In the case of mono-substituted and multi-substituted compounds, the substituted group may include a branched C₃₊ alkyl, a straight chain C₁₊ alkyl, a branched C₃₊ alkylene, a straight chain C₂₊ alkylene, a phenyl or a combination thereof. By way of example, at least one of the substituted groups include a branched C₃₊ alkyl, a straight chain C_1-12 alkyl, a branched C_3-12 alkylene, a straight chain C_2-12 alkylene, a phenyl or a combination thereof. By way of further example, at least one of the substituted groups include a branched C_3-4 alkyl, a straight chain C_1-4 alkyl, a branched C_3-4 alkylene, straight chain C_2-4 alkylene, a phenyl or a combination thereof. Examples of various aryls include, without limitation, benzene, toluene, xylene (dimethylbenzene), ethyl benzene, para xylene, meta xylene, ortho xylene, C₉₊ aromatics, butyl benzene, pentyl benzene, hexyl benzene, heptyl benzene, octyl benzene, nonyl benzene, decyl benzene, undecyl benzene, and isomers thereof.

Fused aryls will generally consist of bicyclic and polycyclic aromatic hydrocarbons, in either an unsubstituted, mono-substituted, or multi-substituted form. In the case of mono-substituted and multi-substituted compounds, the substituted group may include a branched C₃₊ alkyl, a straight chain C₁₊ alkyl, a branched C₃₊ alkylene, a straight chain C₂₊ alkylene, a phenyl or a combination thereof. By way of example, at least one of the substituted groups include a branched C_3-4 alkyl, a straight chain C_1-4 alkyl, a branched C_3-4 alkylene, straight chain C_2-4 alkylene, a phenyl or a combination thereof. Examples of various fused aryls include, without limitation, naphthalene, anthracene, and isomers thereof.

Polycyclic compounds will generally consist of bicyclic and polycyclic hydrocarbons, in either an unsubstituted, mono-substituted, or multi-substituted form. Although polycyclic compounds generally include fused aryls, as used herein the polycyclic compounds generally have at least one saturated or partially saturated ring. In the case of mono-substituted and multi-substituted compounds, the substituted group may include a branched C₃₊ alkyl, a straight chain C₁₊ alkyl, a branched C₃₊ alkylene, a straight chain C₂₊ alkylene, a phenyl or a combination thereof. By way of example, at least one of the substituted groups include a branched C_3-4 alkyl, a straight chain C_1-4 alkyl, a branched C_3-4 alkylene, straight chain C_2-4 alkylene, a phenyl or a combination thereof. Examples of various fused aryls include, without limitation, tetrahydronaphthalene and decahydronaphthalene, and isomers thereof.

The C₄₊ alcohols may also be cyclic, branched or straight chained, and have from 4 to 30 carbon atoms. In general, the C₄₊ alcohols may be a compound according to the formula R¹—OH, wherein R¹ is a member selected from a branched C₄₊ alkyl, straight chain C₄₊ alkyl, a branched C₄₊ alkylene, a straight chain C₄₊ alkylene, a substituted C₅₊ cycloalkane, an unsubstituted C₅₊ cycloalkane, a substituted C₅₊ cycloalkene, an unsubstituted C₅₊ cycloalkene, an aryl, a phenyl or combinations thereof. Examples of desirable C₄₊ alcohols include, without limitation, butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptyldecanol, octyldecanol, nonyldecanol, eicosanol, uneicosanol, doeicosanol, trieicosanol, tetraeicosanol, or isomers thereof.

In some embodiments, a condensation product stream comprising C₄₊ compounds can be fractionated into various product streams, such as gasoline, jet fuel (kerosene), diesel fuel, and aromatics. For example, the condensation product stream may be passed through a three-phase separator to separate the condensation product stream into an acid condensation gas stream, an organic stream, and an aqueous stream. The organic stream and aqueous stream can be separated by density difference, while the acid condensation gas stream comprising uncondensed gases can be recycled to the acid condensation reactor to generate additional C₄₊ compounds. In some embodiments, a gas transport device, such as a blower or compressor, can be configured in the acid condensation gas stream to control the recycle pressure. In some embodiments, an optional purge stream may also be used to control the pressure of the recycle loop in the acid condensation gas stream. In some embodiments, the aqueous stream is discarded from the process, or further processed in downstream process units.

In some embodiments, the organics stream is fractionated in a distillation column to separate the organic stream into a light product stream and a heavy product stream. In some embodiments, the distillation unit is configured to remove co-boiling contaminants for benzene, toluene, or a combination thereof.

In some embodiments, the distillation column is configured to generate a heavy stream that is free or substantially free of co-boiling non-aromatic contaminants for benzene. The distillation column may remove co-boiling nonaromatic contaminants for benzene by fractionating the organic stream into a C₆₋ stream comprising benzene, co-boiling non-aromatic contaminants for benzene, and lighter products through the light product stream. The distillation column may further fractionate the organic stream into a heavy product stream comprising C₇₊ compounds.

In some embodiments, the distillation column is configured to generate a heavy stream that is free or substantially free of co-boiling nonaromatic contaminants for toluene. The distillation column may remove co-boiling nonaromatic contaminants for toluene by fractionating the organic stream into a C₇₋ or C₈₋ stream comprising toluene, co-boiling nonaromatic contaminants for toluene, and lighter products through the light product stream. The distillation column may further fractionate the organic stream into a heavy product stream comprising C₈₊ or C₉₊ compounds.

In some embodiments, the heavy product stream is fractionated in a distillation column to separate the heavy product stream comprising C₇₊ compounds, C₈₊ compounds, or C₉₊ compounds into the mixed aromatic feed stream and a heavy product stream. In some embodiments, the distillation column is configured to fractionate the heavy product stream 140 into a mixed aromatic feed stream 16 comprising C₇₊ compounds and a heavy product feed stream comprising C₁₁₊ compounds. In some embodiments, the mixed aromatic feed stream comprises C₇₊ compounds, or C₈₊ compounds, or C₉₊ compounds, or C_7-10 compounds, or C_8-10 compounds, or C_9-10 compounds.

In some embodiments, the heavy stream may be further separated for use as kerosene (e.g., C_11-14 as jet fuel use), diesel fuel use (e.g., C_12-24), and lubricants or fuel oils (e.g., C₂₅₊). Alternatively, the heavy stream may be cracked to produce addition fractions for use in gasoline, kerosene, aromatics, and/or diesel fractions.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention pertains. All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and/or ordinary meanings of the defined terms. As used herein, the terms “include” and “including” have the same meaning as the terms “comprise” and “comprising.” The terms “comprise” and “comprising” should be interpreted as being “open” transitional terms that permit the inclusion of additional components further to those components recited in the claims. The terms “consist” and “consisting of” should be interpreted as being “closed” transitional terms that do not permit the inclusion of additional components other than the components recited in the claims. The term “consisting essentially of” should be interpreted to be partially closed and allowing the inclusion only of additional components that do not fundamentally alter the nature of the claimed subject matter. As used herein, the singular forms “a”, “an”, and “the” include plural embodiments unless the context clearly dictates otherwise. The modifier “about” used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (for example, it includes at least the degree of error associated with the measurement of the particular quantity). The modifier “about” should also be considered as disclosing the range defined by the absolute values of the two endpoints. For example, the expression “from about 2 to about 4” also discloses the range “from 2 to 4.” The term “about” may refer to plus or minus 10% of the indicated number. For example, “about 10%” may indicate a range of 9% to 11%, and “about 1” may mean from 0.9-1.1.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention pertains. All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and/or ordinary meanings of the defined terms.

The present invention has been described in terms of one or more preferred embodiments, and it should be appreciated that many equivalents, alternatives, variations, and modifications, aside from those expressly stated, are possible and within the scope of the invention.

EXAMPLES

The acid condensation (AC) catalyst is subject to producing coke, which forms from certain components in the hydrodeoxygenation (HDO) Product Stream. The coke needs to be oxidised to CO₂ by burning it off the catalyst at high temperature. This procedure is done only every 24 hours to restore the activity of the AC Catalyst. Different HDO product components have different propensities to laydown coke on the AC catalyst. Generally, those which are most volatile and have only 1 or 2 oxygen atoms remaining generate the least coke. Conversely, components of lower volatility with >3 oxygen atoms remaining tend to produce the most coke. Thus, it is desirable to not send the least volatile components over the AC catalyst.

To separate the more volatile components from the less volatile components an equipment item called a Selective Vaporizer is employed. Hot AC Recycle gas is supplied to the bottom of a bed of packing, which may be random or structured. The HDO Heavies stream is preheated & introduced to the top of the packed bed using a liquid distributor or a 2-phase inlet device. Without wishing to be bound by theory, the rising hot gases strip out the more volatile components in the HDO Heavies stream, while the less volatile ones collect in the sump of the vessel to be purged from the system. The purged bottoms material can be fed to a conventional refinery process such as a fluid catalytic cracking (FCC) to make use of the carbon it contains.

By removing the less volatile components from the HDO Heavies the AC catalyst coke yield is substantially reduced from around 2 wt % of the feed carbon to about 1.5 wt %. The selective vaporizer has also been shown to remove the majority of inorganic contaminants which accumulation in the HDO Heavies. This should reduce the degree of fouling in downstream equipment.

Referring to FIG. 1, The preheated AC Recycle gas stream (1) is introduced to the upper section of the Selective Vaporizer (A) below a bed of packing. HDO Heavies in stream (4) from the bottom of the HDO Flash Drum (not shown) are preheated in the HDO Heavies Preheater (B) to help the volatile components in the stream vaporize in the Selective Vaporizer (A). The preheated HDO Heavies (5) are introduced to the top of the packed bed via a distribution device.

The more volatile components in the HDO Heavies will be vaporized over the bed of packing by the hot AC Recycle gas and pass through the demister pad to be mixed into the combined AC feed stream (6). These more volatile components should not cause a disproportionately higher coke yield on the AC catalyst beds. The less volatile components which are more likely to cause a disproportionately higher coke yield on the AC catalyst beds pass out of the packing and flow into the lower section.

The lower section contains another packed bed and has a Superheated HP Steam stream (3) introduced below it. The purpose of the steam is to strip out any volatile components which may have been entrained into the liquid leaving the packed bed in the upper section of the vessel. Volatile components in the HDO Heavies Purge stream (7), would likely degas as the stream is letdown in pressure and cooled for OSBL storage with the potential to overpressure an atmospheric storage vessel.

In some cases, the systems and methods disclosed herein may include a Selective vaporizer bypass line (2) which fluidly connects the preheated AC recycle gas stream (1) and the overhead gas to AC stream (i.e., the AC feed stream) (6).

Example 1

A large sample of HDO Heavies was tested in a vapor circulation rig at a number of different vaporization temperatures and gas to liquid feed ratios. A synthetic blend of recycle gas was prepared for the test to replicate the molecular weight and specific heat capacity of the actual AC recycle gas as closely as possible.

Preheated recycle vapor was introduced towards the bottom of the vaporizer, beneath the lower packed bed. Preheated liquid was introduced between the upper and lower packed beds with heating applied to both of them. Overhead vapors were condensed and collected in a receiver, while the vaporizer bottoms liquids were removed on a batch basis and collected in a container.

TABLE 1
Conditions used for each set of splits, where one split includes
condensed overhead vapors and vaporizer bottoms liquids.

		Target	Vap.			Liquid	Recycle
Set	Run	Gas Inlet	Bottoms	Overheads	Bottoms	Feed	rate,	Gas:Liquid
Num.	Num.	T, ° C.	T, ° C.	Split, %	Split, %	rate, g/hr	g/hr	Ratio

1	1	160	156.2	15.6	84.4	200	100	0.5
	2	180	167.6	18.4	81.6
	3	200	191.8	23.7	76.3
	4	220	215.9	27.6	72.4
	5	240	234.3	25.3	74.7
2	1	160	151.2	26.7	73.3	200	200	1.0
	2	180	170.7	24.0	76.0
	3	200	198.6	27.4	72.6
	4	220	218.7	29.0	71.0
	5	240	240.7	31.6	68.4
3	1	160	143.1	22.1	77.9	200	300	1.5
	2	180	174.7	27.8	72.2
	3	200	197.3	27.7	72.3
	4	220	219.7	32.9	67.1
	5	240	240.0	42.9	57.1
4	1	160	156.6	22.6	77.4	200	400	2.0
	2	180	177.9	28.3	71.7
	3	200	201.4	30.2	69.8
	4	220	221.2	41.6	58.4
	5	240	241.2	48.4	51.6
5	1	160	154.8	25.8	74.2	200	600	3.0
	2	180	176.3	31.0	69.0
	3	200	201.2	43.6	56.4
	4	220	221.7	51.6	48.4
	5	240	241.2	58.5	41.5
6	1	160	156.5	29.0	71.0	200	800	4.0
	2	180	177.2	45.2	54.8
	3	200	196.8	48.8	51.2
	4	220	216.9	56.4	43.6
	5*	240	239.1	62.8	37.2
7	1	160	160.3	33.1	66.9	200	1000	5.0
	2	180	176.9	38.5	61.5
	3	200	197.6	50.5	49.5
	4	220	217.8	58.7	41.3
	5*	240	241.4	64.1	35.9
8	1	220	217.1	70.7	29.3	125	1000	8.0
	2	240	238.9	78.1	21.9
9	1	220	217.5	73.7	26.3	100	1000	10.0
	2*	240	238.9	83.8	16.2

A selection of the bottoms and overheads samples from the vaporization work were subsequently tested on an AC unit to determine their relative coke yields (Table 2). A model AC feed was created that produced a 1% coke yield across the AC catalyst. Individual samples from the vaporization test were then blended with the model feed in a ratio where 15% of the total carbon in the combined feed was coming from the selected sample.

Referring to FIG. 3, levels of inorganic contaminants in the vaporizer cuts were also analyzed by Inductively coupled plasma-optical emission spectrometry (ICP-OES), confirming that the contaminants concentrate up in the bottoms cut, leaving the overheads with much reduced levels of contamination.

TABLE 2
Relative coke yields of splits from 3 exemplary samples.

		Coke Yield
	Fraction	(%)

	Overhead 1	1.6
	Bottoms 1	2.6
	Overhead 2	1.8
	Bottoms 2	2.4
	Overhead 3	2
	Bottoms 3	2.8
	PV	2.12

Example 2

A selective vaporizer was implemented in an integrated HDO and AC lab scale process, close to the preferred configuration for a commercial plant. Several different sources of HDO Heavies were used in these tests.

FIG. 5 shows the results of the first run of the integrated selective vaporizer, showing the C₅₊ product yield (x-axis) as a percentage of the carbon in the feed to the overall process (y-axis). It can be seen that the selective vaporizer reduces the carbon yield on the AC catalyst relative to the no purge case, for a modest reduction in overall yield of C₅₊ products. The PV purge (from the bottom of the HDO Product Flash Drum) reduces the carbon yield on the AC catalyst much more, but has a significant hit on the overall yield of C₅₊ products. In practice it is expected that the loss in product yield will be somewhat counteracted by an increase in onstream time due to less time off stream for cleaning of equipment. FIG. 6 shows data from the second run of the integrated selective vaporizer, with similar results as demonstrated in FIG. 5, though slightly reduced losses for the SV and PV purge cases due to optimization of the operating conditions of the process.