Method for producing graphene using direct liquid injection chemical vapor deposition of biocrude or biosynthetic crude

Abstract

The present disclosure relates to a method for producing graphene using direct liquid injection chemical vapor deposition (DLI-CVD) of biocrude. Biocrude derived from biomass or waste feedstocks is subjected to one or more conditioning operations, including filtration, dewatering, desalting, demetallization, adsorption treatment, and fractionation to obtain a precursor suitable for direct liquid injection. The conditioned biocrude is injected into a heated vaporization zone to generate a carbon-containing vapor stream, which is introduced into a chemical vapor deposition reactor comprising a metal catalyst substrate under a controlled gas atmosphere. The vapor decomposes at elevated temperatures to form graphene or graphene-containing carbon structures. The method improves injection stability, reduces coking and fouling, and enables effective utilization of complex biocrude feedstocks for producing high-quality graphenic materials.

Description

[0001] METHOD FOR PRODUCING GRAPHENE USING DIRECT EIQUID INJECTION CHEMICAE VAPOR DEPOSITION OF BIOCRUDE OR BIOSYNTHETIC CRUDE FIELD OF INVENTION:

[0002] The present invention relates to a sustainable method for producing graphene using biocrude or biosynthetic crude as a carbon source in a Direct Liquid Injection Chemical Vapor Deposition (DLLCVD) process. More specifically, it utilizes biocrude derived from hydrothermal liquefaction (HTL) of algal biomass and other carbon-rich waste feedstocks.

[0003] BACKGROUND OF INVENTION:

[0004] Graphene is a two-dimensional carbon material exhibiting exceptional electrical, thermal, mechanical, and barrier properties. Due to these characteristics, graphene and graphenic films are widely utilized in electronics, sensors, coatings, membranes, conductive layers, energy devices, thermal management systems, structural composites, and other high-value applications.

[0005] Chemical vapor deposition (CVD) on catalytic substrates such as copper and nickel is a well-established technique for producing high-quality graphene films. Conventional CVD graphene synthesis typically relies on fossil-derived gaseous hydrocarbons, including methane, acetylene, or ethylene, as carbon precursors. While such approaches are effective, they depend on purified gaseous feed infrastructure and do not inherently support circular carbon utilization or waste valorization.

[0006] Liquid-precursor-based graphene synthesis methods have also been explored. However, many known liquid precursors are relatively simple and purified compounds, such as alcohols, aromatics, or petrochemical liquids. In contrast, renewable and waste-derived liquid carbon feedstocks, including biocrude and biosynthetic crude, are chemically complex and heterogeneous. Such feedstocks typically contain oxygenates, nitrogen-containing compounds, sulfur-containing compounds, water, suspended solids, char fines, salts, ash-forming species, tracemetals, heavy fractions, unstable polar compounds, and coking-promoting constituents.

[0007] Due to this complexity, direct use of raw biocrude in conventional direct liquid injection chemical vapor deposition (DLI-CVD) systems presents significant technical challenges. These challenges include unstable injection, incomplete vaporization, condensation in transfer lines, upstream coking, injector fouling, catalyst poisoning, non-uniform carbon decomposition, excessive soot formation, and the formation of defective or predominantly amorphous carbon rather than controlled graphenic structures.

[0008] Various approaches have been proposed in the prior art to address graphene synthesis. For instance, conventional CVD methods, such as those disclosed in US8470400B2, utilize gaseous hydrocarbon precursors under controlled atmospheres to deposit graphene on catalytic substrates. While such methods produce high-quality graphene, they rely on fossil-based gaseous inputs and require complex gas handling systems.

[0009] Further, certain disclosures, including WO2013066269, describe the use of liquid carbon precursors in CVD processes. However, such approaches generally employ relatively simple and purified liquid compounds and do not address the challenges associated with complex and heterogeneous feedstocks such as biocrude.

[0010] Additionally, methods such as those disclosed in US 11274042 describe the conversion of biomass-derived bio-oils into carbon materials through pyrolysis and graphitization. However, such approaches do not involve controlled vapor-phase deposition and are not suitable for producing high-quality graphene films using CVD techniques.

[0011] Accordingly, existing approaches fail to address the challenges associated with utilizing renewable and waste-derived liquid carbon feedstocks, particularly biocrude and biosynthetic crude, in direct liquid injection chemical vapor deposition processes.There exists a need for an improved method that enables effective utilization of such complex feedstocks in DLI-CVD graphene synthesis. There is also a need for methods that define appropriate refining, fraction selection, conditioning, vaporization behaviour, atmosphere control, and catalytic deposition conditions to achieve stable processing and reproducible formation of graphene and graphenic materials.

[0012] The present disclosure addresses these needs by providing a method for producing graphene using direct liquid injection chemical vapor deposition (DLI-CVD) of biocrude, wherein the liquid carbon feedstock is conditioned and processed to enable stable injection, controlled vaporization, and effective graphene deposition on a catalytic substrate.

[0013] OBJECT OF THE INVENTION

[0014] The principal object of the present disclosure is to provide a method for producing graphene using direct liquid injection chemical vapor deposition (DLI-CVD) of biocrude or biosynthetic crude.

[0015] Another object of the present disclosure is to provide a method for producing graphene that utilizes sustainable, renewable, and waste-derived carbon sources.

[0016] Another object of the present disclosure is to provide a method for producing graphene that replaces fossil-based gaseous precursors with biocrude or biosynthetic crude.

[0017] Another object of the present disclosure is to provide a method for producing graphene that is scalable and compatible with existing chemical vapor deposition (CVD) infrastructure.

[0018] Another object of the present disclosure is to provide a method for producing graphene that supports a circular economy and reduces carbon footprint.Another object of the present disclosure is to provide a method wherein biocrude or biosynthetic crude is conditioned to render it suitable for direct liquid injection chemical vapor deposition.

[0019] Another object of the present disclosure is to provide a method that improves injection stability and vaporization behavior of complex liquid carbon precursors.

[0020] Another object of the present disclosure is to provide a method that reduces upstream coking, fouling, and injector blockage during processing.

[0021] Another object of the present disclosure is to provide a method that enables controlled deposition of graphene or graphene-containing structures on a catalytic substrate.

[0022] Another object of the present disclosure is to provide a system for producing graphene comprising a direct liquid injection unit, vaporization section, chemical vapor deposition reactor, and gas handling section.

[0023] SUMMARY OF THE INVENTION:

[0024] This summary is provided to introduce a selection of concepts in a simplified form that are further disclosed in the detailed description of the invention. This summary is not intended to identify key or essential inventive concepts of the claimed subject matter, nor is it intended to determine the scope of the claimed subject matter.

[0025] The present invention is all about a method for producing graphene using direct liquid injection chemical vapor deposition (DLI-CVD) of biocrude or biosynthetic crude.

[0026] The main aspect of the present invention is to provide a method for producing graphene, comprising: obtaining biocrude or biosynthetic crude from hydrothermal liquefaction of algal biomass, carbon-rich feedstocks, or combinations thereof; refining said biocrude or biosynthetic crude to remove impurities; injecting the refined biocrude or biosynthetic crude into a vaporization chamber via direct liquidinjection; introducing the vaporized biocrude or biosynthetic crude into a chemical vapor deposition reactor containing a metal catalyst substrate; and decomposing the vaporized biocrude or biosynthetic crude at high temperature to form graphene on the substrate.

[0027] Another aspect of the present invention is to provide a method for producing graphene from a renewable or waste-derived liquid carbon feedstock, the method comprising: obtaining a liquid carbon feedstock comprising biocrude, upgraded biocrude, bio-oil, biosynthetic crude, or a combination thereof; subjecting the liquid carbon feedstock to one or more conditioning operations selected from filtration, dewatering, solids reduction, desalting, demetallization, heteroatom reduction, adsorption treatment, fractionation, solvent adjustment, viscosity adjustment, catalytic upgrading, and combinations thereof to produce a pre-treated precursor suitable for direct liquid injection chemical vapor deposition; directly injecting the pre-treated precursor into a heated vaporization zone to generate a carbon-containing vapor stream; introducing the carbon-containing vapor stream into a chemical vapor deposition reactor containing a catalytic substrate; and depositing graphene, few-layer graphene, a graphene-rich film, or a graphene-containing carbon nanostructure on the catalytic substrate.

[0028] Another aspect of the present invention is to provide a system for producing graphene from biocrude or biosynthetic crude, comprising: a hydrothermal liquefaction unit for generating biocrude; a biocrude refining unit; a direct liquid injection system; a vaporization unit; and a chemical vapor deposition reactor with a metal catalyst substrate; a gas handling section configured to supply one or more carrier gases, inert gases, reducing gases, or combinations thereof.

[0029] A system for producing graphene from renewable or waste-derived liquid carbon feedstocks, the system comprising: a feedstock supply section configured to provide biocrude, upgraded biocrude, bio-oil, biosynthetic crude, or a combination thereof; pre-treatment section configured to condition said feedstock by one or more operations selected from solids reduction, dewatering, desalting, demetallization,heteroatom reduction, adsorption treatment, fractionation, solvent adjustment, viscosity adjustment, catalytic upgrading, and combinations thereof; a direct liquid injection section configured to meter and inject a pre-treated biocrude precursor; a vaporization section configured to convert the injected precursor into a carbon-containing vapor stream; a chemical vapor deposition reactor containing a catalytic substrate and configured to deposit graphene or a graphene-rich film from said vapor stream; and a gas handling section configured to supply one or more carrier gases, inert gases, reducing gases, or combinations thereof; and optionally, a cooling, transfer, post-treatment, characterization, and / or roll-to-roll substrate handling section

[0030] BRIEF DESCRIPTION OF THE DRAWINGS:

[0031] The foregoing summary, as well as the following detailed description of the invention, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, exemplary constructions of the invention are shown in the drawings.

[0032] Figure 1 illustrates a schematic overall process flow for producing graphene from biocrude or biosynthetic crude using direct liquid injection chemical vapor deposition (DLI-CVD).

[0033] Figure 2 illustrates a schematic diagram of a pre-treatment system configured to condition raw biocrude by reducing solids, water, salts, metals, and other impurities prior to DLI-CVD processing.

[0034] Figure 3 illustrates a schematic diagram of a direct liquid injection and vaporization assembly configured to inject and vaporize a liquid precursor and deliver a carbon-containing vapor stream.

[0035] Figure 4 illustrates a schematic diagram of a chemical vapor deposition reactor system comprising a reactor body, heating zone, gas inlet, and catalytic substrate for graphene deposition.Figure 5 illustrates a schematic process sequence including substrate preparation, precursor introduction, graphene growth, cooling, and optional transfer.

[0036] Figure 6 illustrates a schematic diagram of a pulsed injection system configured to deliver the liquid precursor in discrete pulses to reduce upstream coking.

[0037] Figure 7 illustrates a schematic diagram of a continuous or semi-continuous graphene production system employing a roll-to-roll reactor and a moving catalytic substrate.

[0038] Figure 8 illustrates a conceptual comparative schematic showing differences between untreated biocrude processing and pre-treated biocrude processing, highlighting improved process stability and graphenic deposition in the pre-treated route.

[0039] DETAILED DESCRIPTION OF THE INVENTION:

[0040] Detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, the specific functional and structural details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.

[0041] 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 belongs.

[0042] The present disclosure addresses the aforementioned limitations associated with conventional graphene synthesis techniques and provides an improved method and system for producing graphene from renewable and waste-derived liquid carbon feedstocks. The objects, features, and advantages of the present disclosure will bedescribed in greater detail in the following description. The subsequent description sets forth various embodiments and specific details for purposes of illustration and explanation. However, it will be understood by a person skilled in the art that the present disclosure is not limited to the embodiments described herein, and that various modifications, variations, and substitutions may be made without departing from the scope and spirit of the present disclosure as defined by the appended claims.

[0043] It must also be noted that, as used herein and in the appended claims, the singular forms "a", "an," and "the" include plural references unless the context clearly dictates otherwise. Although any systems and methods similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present invention, the preferred systems are now described.

[0044] Throughout the invention, for the purposes of this disclosure, the following definitions shall have the meanings as described below:

[0045] “Biocrude” means a liquid organic product derived from biomass conversion, particularly hydrothermal liquefaction of wet biomass, and includes crude and partially upgraded liquid fractions containing hydrocarbons and / or oxygenated organic compounds.

[0046] “Biosynthetic crude” means a renewable or waste-derived carbon-rich liquid generated through one or more hydrothermal, thermochemical, catalytic, pyrolytic, co-processing, depolymerization, or upgrading routes, including routes involving mixed biomass and plastic-containing feedstocks.

[0047] “Pretreated biocrude precursor” means a biocrude, upgraded biocrude, bio-oil, biosynthetic crude, or fraction or blend thereof that has been processed to render it suitable or more suitable for direct liquid injection and graphene growth by reducing one or more of water, suspended solids, salts, ash-forming species, heavy residues, unstable polar compounds, heteroatoms, and catalyst-poisoning impurities.“Graphene” includes monolayer graphene, bilayer graphene, few-layer graphene, multilayer graphene, graphene -rich carbon film, graphenic film, and graphenecontaining carbon nanostructures unless the context requires a narrower meaning.

[0048] “Direct liquid injection” or “DLI” means introducing a metered liquid feed directly into a heated vaporization zone, flash-vaporization zone, atomization zone, or carrier gas stream for delivery to a deposition reactor.

[0049] “Suitable for DLI-CVD” means capable of being injected, vaporized, transported, and deposited under graphene-growth conditions without unacceptable nozzle plugging, condensation, catastrophic fouling, upstream coking, or complete failure of graphenic deposition.

[0050] The main embodiment of the present invention is to provide a method for producing graphene using direct liquid injection chemical vapor deposition (DLI-CVD) of biocrude or biosynthetic crude.

[0051] As per the detailed embodiment of the present invention, a method for producing graphene, comprising:

[0052] a) obtaining biocrude or biosynthetic crude from hydrothermal liquefaction of algal biomass, carbon-rich feedstocks, or combinations thereof;

[0053] b) refining said biocrude or biosynthetic crude to remove impurities; c) injecting the refined biocrude or biosynthetic crude into a vaporization chamber via direct liquid injection;

[0054] d) introducing the vaporized biocrude or biosynthetic crude into a chemical vapor deposition reactor containing a metal catalyst substrate; and

[0055] e) decomposing the vaporized biocrude or biosynthetic crude at high temperature to form graphene on the substrate.

[0056] As per the detailed embodiment of the present invention, wherein the feedstock for biocrude or biosynthetic crude comprises microalgae, seaweed, municipal sludge,municipal solid waste (MSW), agricultural waste, food waste, animal waste, industrial waste, plastic waste, or combinations thereof.

[0057] As per the detailed embodiment of the present invention, wherein the biocrude or biosynthetic crude is refined using distillation, catalytic upgrading, adsorption, or combinations thereof to reduce oxygen, nitrogen, sulfur, or other impurities.

[0058] As per the detailed embodiment of the present invention, wherein the metal catalyst substrate comprises copper, nickel, cobalt, iron, an alloy thereof, or a combination thereof.

[0059] As per the detailed embodiment of the present invention, wherein the vaporization temperature is about 250°C to about 500°C or more, and the chemical vapor deposition reactor temperature is about 900°C to about 1000°C or more.

[0060] As per the detailed embodiment of the present invention, wherein the graphene is monolayer graphene bilayer graphene, trilayer graphene, few-layer graphene, multilayer graphene, graphene-rich films, graphenic carbon films, and graphenecontaining carbon nanostructures.

[0061] As per the detailed embodiment of the present invention, further comprising transferring the graphene from the catalyst substrate onto a target substrate.

[0062] As per the detailed embodiment of the present invention, wherein the chemical vapor deposition reactor is operated under an inert gas atmosphere, a hydrogeninert gas atmosphere, or combinations thereof.

[0063] As per the detailed embodiment of the present invention, a method for producing graphene from a renewable or waste-derived liquid carbon feedstock, the method comprising:

[0064] (a) obtaining a liquid carbon feedstock comprising biocrude, upgraded biocrude, bio-oil, biosynthetic crude, or a combination thereof; (b) subjecting the liquid carbon feedstock to one or more conditioning operations selected from filtration, dewatering, solids reduction,desalting, demetallization, heteroatom reduction, adsorption treatment, fractionation, solvent adjustment, viscosity adjustment, catalytic upgrading, and combinations thereof to produce a pretreated precursor suitable for direct liquid injection chemical vapor deposition;

[0065] (c) directly injecting the pre-treated precursor into a heated vaporization zone to generate a carbon-containing vapor stream;

[0066] (d) introducing the carbon-containing vapor stream into a chemical vapor deposition reactor containing a catalytic substrate; and (e) depositing graphene, few-layer graphene, a graphene-rich film, or a graphene-containing carbon nanostructure on the catalytic substrate. As per the detailed embodiment of the present invention, wherein the renewable or waste-derived liquid carbon feedstock is derived from hydrothermal liquefaction, co-liquefaction, pyrolysis, catalytic depolymerization, thermal conversion, upgrading, or combinations thereof.

[0067] As per the detailed embodiment of the present invention, wherein the conditioning step comprises selecting a fraction having reduced coking tendency and improved suitability for vaporization relative to an unfractionated feed.

[0068] As per the detailed embodiment of the present invention, wherein the conditioning step comprises reducing one or more of suspended solids, water, salts, ash-forming species, oxygen-containing compounds, nitrogen-containing compounds, sulfur-containing compounds, and metal-containing impurities.

[0069] As per the detailed embodiment of the present invention, wherein the direct liquid injection is continuous, pulsed, intermittent, atomized, nebulized, or combinations thereof.

[0070] As per the detailed embodiment of the present invention, wherein the conditioning step comprises adsorption polishing to reduce catalyst-poisoning impurities prior to direct liquid injection.As per the detailed embodiment of the present invention, wherein the liquid carbon feedstock comprises a co-processed biomass-and-plastic-derived biosynthetic crude.

[0071] As per the detailed embodiment of the present invention, wherein a transfer line between the vaporization zone and the chemical vapor deposition reactor is heated to reduce condensation and upstream fouling.

[0072] As per the detailed embodiment of the present invention, wherein the process is operated such that upstream coking is lower for the conditioned precursor than for the corresponding untreated feedstock under otherwise comparable DLI-CVD conditions.

[0073] As per the detailed embodiment of the present invention, wherein the biocrude or biosynthetic crude is subjected to one or more conditioning operations selected from filtration, dewatering, solids reduction, desalting, demetallization, heteroatom reduction, adsorption treatment, fractionation, solvent adjustment, viscosity adjustment, catalytic upgrading, and combinations thereof prior to direct liquid injection

[0074] As per the detailed embodiment of the present invention, wherein the conditioned precursor is delivered at a flow rate of about 0.02 mL / min to about 1.5 mL / min.

[0075] As per the detailed embodiment of the present invention, wherein the vaporization zone is maintained at about 250°C to about 500°C or more.

[0076] As per the detailed embodiment of the present invention, wherein the catalytic substrate comprises copper foil having a thickness of about 10 pm to about 100 pm.

[0077] As per the detailed embodiment of the present invention, wherein the substrate is annealed under hydrogen-containing atmosphere prior to precursor introduction.

[0078] As per the detailed embodiment of the present invention, wherein the direct liquid injection is pulsed with pulse durations of about 0.1 seconds to about 10 seconds.As per the detailed embodiment of the present invention, wherein the precursor is a selected intermediate fraction of hydrothermal-liquefaction-derived biocrude or biosynthetic crude or biooil or combinations thereof.

[0079] As per the detailed embodiment of the present invention, wherein the precursor is a demetallized and desalted biocrude fraction.

[0080] As per the detailed embodiment of the present invention, a precursor composition for producing graphene by direct liquid injection chemical vapor deposition is provided. The precursor composition comprising a pre-treated biocrude precursor derived from a renewable or waste-derived liquid carbon feedstock, wherein the precursor composition has been conditioned by one or more of solids reduction, dewatering, desalting, demetallization, heteroatom reduction, adsorption treatment, fractionation, solvent adjustment, viscosity adjustment, or combinations thereof to render the precursor composition suitable for direct liquid injection and graphene deposition.

[0081] As per the detailed embodiment of the present invention, wherein the precursor composition is derived from hydrothermal-liquefaction biocrude.

[0082] As per the detailed embodiment of the present invention, wherein the precursor composition comprises a selected fraction of biocrude or biosynthetic crude or biooil having reduced heavy residue relative to a raw unfractionated precursor.

[0083] As per the detailed embodiment of the present invention, A system for producing graphene from biocrude or biosynthetic crude, comprising:

[0084] (a) a hydrothermal liquefaction unit for generating biocrude; (b) a biocrude refining unit;

[0085] (c) a direct liquid injection system;

[0086] (d) a vaporization unit; and

[0087] (e) a chemical vapor deposition reactor with a metal catalyst substrate. (f) a gas handling section configured to supply one or more carrier gases, inert gases, reducing gases, or combinations thereofAs per the detailed embodiment of the present invention, wherein the biocrude feedstock is selected from microalgae, macroalgae, seaweed, municipal sludge, municipal solid waste (MSW), agricultural waste, food waste, animal waste, industrial waste, or combinations thereof.

[0088] As per the detailed embodiment of the present invention, wherein the plastic waste comprises polycarbonate, polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polyvinyl chloride, polyamides, mixed plastic wastes, or combinations thereof.

[0089] As per the detailed embodiment of the present invention, wherein the chemical vapor deposition reactor is operated under an inert gas atmosphere, a hydrogeninert gas mixture, or combinations thereof.

[0090] As per the detailed embodiment of the present invention, further comprising a renewable power source selected from solar, wind, biomass, hydrogen-based systems, or combinations thereof.

[0091] As per the detailed embodiment of the present invention, A system for producing graphene from renewable or waste-derived liquid carbon feedstocks, the system comprising:

[0092] (a) a feedstock supply section configured to provide biocrude, upgraded biocrude, bio-oil, biosynthetic crude, or a combination thereof; (b) a pre-treatment section configured to condition said feedstock by one or more operations selected from solids reduction, dewatering, desalting, demetallization, heteroatom reduction, adsorption treatment, fractionation, solvent adjustment, viscosity adjustment, catalytic upgrading, and combinations thereof;

[0093] (c) a direct liquid injection section configured to meter and inject a pretreated biocrude precursor;

[0094] (d) a vaporization section configured to convert the injected precursor into a carbon-containing vapor stream;(e) a chemical vapor deposition reactor containing a catalytic substrate and configured to deposit graphene or a graphene-rich film from said vapor stream; and

[0095] (f) a gas handling section configured to supply one or more carrier gases, inert gases, reducing gases, or combinations thereof.

[0096] As per the detailed embodiment of the present invention, wherein the pre-treatment section comprises one or more of a filter, centrifuge, separator, dryer, desalting unit, adsorbent bed, demetallizations unit, fractionation unit, or upgrading unit.

[0097] As per the detailed embodiment of the present invention, wherein the direct liquid injection section comprises a metering pump, injector nozzle, ultrasonic atomizer, pulsed injector, capillary injector, or combinations thereof.

[0098] As per the detailed embodiment of the present invention, wherein the direct liquid injection section further comprises a pulse controller configured to operate the injector in an intermittent mode.

[0099] As per the detailed embodiment of the present invention, wherein the heated transfer line is configured to maintain the precursor vapor above its condensation temperature prior to entry into the chemical vapor deposition reactor.

[0100] The specification is further explained below, providing a comprehensive understanding of the invention:

[0101] 1. General Inventive Concept

[0102] The present disclosure provides a route for producing graphene from biocrude or biosynthetic crude using direct liquid injection chemical vapor deposition.

[0103] In certain embodiments, the disclosure further recognizes that biocrude or biosynthetic crude or biooil may be refined, fractionated, conditioned, or otherwise treated to improve suitability for DLI-CVD graphene growth. Such treatment may address feed heterogeneity, solids, salts, heavy fractions, heteroatoms, catalyst-poisoning species, and coking-promoting constituents.Accordingly, the inventive contribution may reside in one or more of:

[0104] • using biocrude or biosynthetic crude or biooil as a liquid carbon precursor for DLI-CVD graphene formation;

[0105] • selecting a graphene- suitable fraction of biocrude or biosynthetic crude or biooil;

[0106] • reducing or removing catalyst-poisoning impurities;

[0107] • controlling precursor viscosity and volatility for DLI;

[0108] • reducing line fouling and upstream coking;

[0109] • matching precursor composition to catalyst and reactor conditions;

[0110] and / or

[0111] • integrating waste-derived liquid carbon generation with graphene synthesis.

[0112] 2. Feedstock Sources

[0113] The renewable or waste-derived liquid carbon feedstock may be derived from one or more of:

[0114] Microalgae, macroalgae or seaweed, cyanobacteria, aquatic biomass, wastewater-grown biomass, sewage sludge, industrial sludge, food waste, agricultural residues, animal waste, lignocellulosic biomass, municipal solid waste-derived organics, organic industrial residues, mixed biomass streams, plastic-containing waste streams, combinations of any of the foregoing

[0115] In certain preferred embodiments, the feedstock is converted to biocrude by hydrothermal liquefaction. In other embodiments, the feedstock is converted into biosynthetic crude by co-liquefaction, thermal conversion, catalytic upgrading, co-processing, or combinations thereof.

[0116] 3. Feedstock Conversion to Biocrude or Biosynthetic Crude

[0117] In certain embodiments, wet biomass is subjected to hydrothermal liquefaction at temperatures of about 220°C to about 420°C, preferably about 260°C to about 38O°C, under pressure sufficient to maintain a substantially liquid reactionphase. The resulting reaction mixture may be separated into gas, aqueous phase, solids, and biocrude.

[0118] The present disclosure is not limited to any specific conversion reactor and may be practiced using batch, semi-batch, continuous, tubular, stirred, loop, recirculating, or modular conversion systems.

[0119] 4. Pre-treatment and Conditioning of the Liquid Precursor

[0120] In preferred embodiments, raw biocrude is not directly fed to the DLI-CVD reactor. Instead, it is subjected to one or more pre-treatment steps.

[0121] 4.1 Solids Reduction

[0122] The liquid precursor may be treated by settling, centrifugation, filtration, hydrocyclone separation, membrane separation, depth filtration, cartridge filtration, or combinations thereof to remove suspended solids, char fines, residual catalyst, ash-forming particles, and other particulates.

[0123] In certain embodiments, the solids content entering the direct liquid injection system is reduced to less than about 5 wt.%, less than about 1 wt.%, less than about 0.5 wt.%, or less than about 0.1 wt.%.

[0124] 4.2 Dewatering

[0125] Water may be reduced by gravity separation, thermal dehydration, vacuum treatment, membrane separation, desiccant treatment, or combinations thereof.

[0126] In certain embodiments, water content is reduced to less than about 20 wt.%, less than about 10 wt.%, less than about 5 wt.%, or less than about 2 wt.% prior to injection.

[0127] 4.3 Desalting and Ash Control

[0128] Where the feedstock source comprises saline biomass, marine biomass, sludge, wastewater-derived feedstocks, or mixed waste streams, desalting and ashreduction may be carried out by washing, phase separation, membrane treatment, adsorption, ion exchange, or combinations thereof.

[0129] 4.4 Demetallization and Impurity Reduction

[0130] Metal-containing impurities and catalyst poisons may be reduced by adsorption over activated carbon, alumina, silica, zeolite, clay, specialty metal scavengers, ion exchange materials, or combinations thereof. In some embodiments, treatment reduces one or more of sodium, potassium, calcium, magnesium, iron, nickel, vanadium, phosphorus, silicon, chlorine, sulfur-containing species, and combinations thereof.

[0131] 4.5 Heteroatom Reduction

[0132] The liquid precursor may be subjected to catalytic upgrading, mild hydro treating, adsorption polishing, solvent extraction, or related treatment to reduce oxygen-containing, nitrogen-containing, or sulfur-containing species.

[0133] 4.6 Fractionation and Volatility Adjustment

[0134] In preferred embodiments, the liquid carbon feedstock is fractionated by atmospheric distillation, vacuum distillation, flash fractionation, wiped-film evaporation, solvent fractionation, or combinations thereof to isolate a fraction or blend having improved suitability for controlled direct liquid injection and vaporization.

[0135] A selected fraction may comprise a light fraction, intermediate fraction, aromatic-enriched fraction, or tailored blend thereof. Heavy fractions with excessive coking tendency may be reduced, excluded, or used only in minor proportions.

[0136] 4.7 Viscosity Adjustment and Blending

[0137] In some embodiments, a selected biocrude fraction is blended with a compatible co-liquid or lighter fraction to obtain a viscosity suitable for the metering pump and injector.4.8 Anti-Coking Measures

[0138] In some embodiments, coking is reduced by controlling precursor residence time in the hottest zones, using pulsed injection, using heated transfer lines, reducing local hot spots, or selecting an appropriate precursor fraction.

[0139] 5. Direct Liquid Injection and Vaporization

[0140] The liquid precursor delivered to the direct liquid injection system may be refined biocrude or biosynthetic crude, or, in preferred embodiments, a further conditioned precursor. The direct liquid injection system may include a metering pump, syringe pump, high-pressure liquid pump, injector nozzle, atomizer, ultrasonic atomizer, nebulizer, capillary injector, pulsed injector, or combinations thereof.

[0141] The precursor may be injected continuously or intermittently. In some embodiments, pulsed injection is used to reduce the thermal residence time of liquid in the upstream vaporization hardware.

[0142] The vaporization zone may be maintained at a temperature of about 250°C to about 650°C, preferably about 250°C to about 500°C, and more preferably about 250°C to about 420°C, depending on precursor composition.

[0143] A heated transfer line may be provided between the vaporizer and the reactor and maintained above the condensation temperature of the precursor vapor.

[0144] 6. Carrier Gas and Atmosphere Control

[0145] One or more gases may be used as carrier gas, inert gas, reducing gas, or atmosphere-control gas, including nitrogen, argon, helium, hydrogen, or combinations thereof.

[0146] In certain embodiments, the catalytic substrate is annealed under inert gas and / or hydrogen before precursor introduction. The precursor vapor is then introduced under a controlled gas atmosphere to promote graphenic deposition while limiting soot formation and catalyst deactivation.7. Catalytic Substrates

[0147] Catalytic substrates may comprise copper, nickel, cobalt, iron, alloys thereof, or combinations thereof. The substrate may be present as foil, thin film, coated support, mesh, wire, moving web, structured metallic support, or combinations thereof.

[0148] Copper may be preferred in embodiments targeting predominantly surface-mediated monolayer or bilayer graphene growth. Nickel or nickel-containing substrates may be preferred in embodiments targeting few-layer graphene or graphene-rich films.

[0149] 8. Graphene Deposition Reactor

[0150] The deposition reactor may be a hot-wall furnace, cold-wall reactor, tubular reactor, vertical reactor, horizontal reactor, roll-to-roll reactor, batch reactor, semi-continuous reactor, or continuous reactor.

[0151] The reactor may be maintained at about 900°C to about 1200°C, preferably about 900°C to about 1100°C, and more preferably about 900°C to about 1050°C. Reactor pressure may be atmospheric, sub-atmospheric, or elevated.

[0152] Deposition conditions may be selected to favour graphenic growth over amorphous carbon deposition by controlling precursor loading, gas flow, vaporization behaviour, catalyst temperature, residence time, and cooling profile.

[0153] 9. Cooling and Optional Graphene Transfer

[0154] After deposition, the catalytic substrate may be cooled under an inert or reducing atmosphere. Cooling rate may be selected to influence carbon precipitation and layer count, especially where nickel or other higher-carbon-solubility catalysts are used.The deposited graphene may remain on the catalytic substrate or may be transferred to a target substrate, including glass, silicon, ceramic, flexible polymer film, oxide-coated substrate, or device substrate.

[0155] 10. Product Characterization

[0156] Graphene or graphene-rich products produced according to the present disclosure may be characterized by Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, four-point probe testing, optical transmittance measurement, or combinations thereof.

[0157] Where experimental data are not yet available, such characterization methods are described as intended or suitable methods for confirming graphene quality, layer count, coverage, and defect level.

[0158] The features of the present invention are further elaborately shown and explained through the figures of the invention, providing a comprehensive understanding of its functionality.

[0159] Figure 1, an overall system (100) is shown for producing graphene from biocrude. Feedstock is first introduced into a feedstock preparation section (110), after which the prepared feed is supplied to a hydrothermal liquefaction unit (120). The output of the hydrothermal liquefaction unit (120) is delivered to a phase separation unit (130) configured to separate gas, aqueous phase, solids, and biocrude-containing fractions. The biocrude-containing fraction is collected in a biocrude recovery vessel (140) and then passed to a pretreatment train (150) for one or more operations selected from solids reduction, dewatering, desalting, demetallization, adsorption treatment, and related conditioning.

[0160] The conditioned material is then passed to a fractionation unit (160) to isolate a selected fraction or blend suitable for DLI-CVD processing. The selected precursor is stored in a conditioned precursor tank (170) and fed to a direct liquid injection system (180). The liquid is then delivered to a vaporization chamber (190) togenerate a carbon-containing vapor stream. The vapor passes through a heated transfer line (200) to a CVD graphene reactor (210). Within the reactor (210), the precursor vapor contacts a catalytic substrate supported by a catalyst substrate holder (220) under a controlled gas atmosphere supplied through a gas supply manifold (230). Following deposition, the product passes to a cooling section (240) and may optionally be delivered to a graphene transfer station (250) for transfer or collection.

[0161] Figure 2 illustrates a pre-treatment system (300) configured to condition raw biocrude prior to DLLCVD processing. The system includes a raw biocrude feed vessel (310) that supplies material to a coarse filtration unit (320) for removal of large particulates. The filtered stream is directed to a centrifuge or separator (330) to further reduce suspended solids.

[0162] A dewatering stage (340) is provided to reduce water content using thermal, vacuum, or separation-based techniques. A desalting stage (350) removes dissolved salts and inorganic species. An adsorption polishing bed (360), which may include activated carbon, alumina, silica, or other adsorbents, is configured to remove catalyst-poisoning impurities.

[0163] A demetallization unit (370) reduces metal contaminants such as iron, sodium, potassium, and other trace metals. The treated stream may be subjected to fractionation in a column or evaporator (380) to isolate a fraction having improved volatility and reduced coking tendency. The resulting conditioned precursor is collected in a treated precursor reservoir (390) for downstream processing.

[0164] Figure 3 illustrates a direct liquid injection and vaporization assembly (400). The assembly includes a precursor reservoir (410) configured to store conditioned liquid precursor, and a metering pump (420) configured to deliver the precursor at a controlled flow rate. An optional pulse controller (430) enables pulsed or intermittent injection.

[0165] The precursor is delivered through an injector nozzle (440) into a vaporization chamber (450), which is surrounded by a heating jacket (460) to maintain atemperature sufficient for rapid vaporization. A carrier gas inlet (470) introduces a gas such as nitrogen, argon, or hydrogen to assist in transport of the vaporized precursor.

[0166] The generated vapor exits through a vapor outlet (480) and is transported via a heated transfer line (490), which is maintained above the condensation temperature to prevent fouling and condensation prior to entering the reactor.

[0167] Figure 4 illustrates a schematic diagram of a graphene deposition reactor system (500) configured for producing graphene from a vaporized biocrude or biosynthetic crude precursor. The system comprises a tubular reactor body (510) that defines a reaction chamber within which graphene growth occurs. The reactor body (510) is positioned within an external furnace or heating zone (520) configured to provide and maintain elevated temperatures required for decomposition of the precursor and formation of graphenic structures.

[0168] A precursor vapor inlet (530) is provided for introducing the vaporized biocrude or biosynthetic crude into the reactor. A carrier or reducing gas inlet (540) is configured to supply one or more gases such as nitrogen, argon, helium, hydrogen, or combinations thereof to control the atmosphere within the reactor.

[0169] A catalyst substrate holder (550) is disposed within the reactor body (510) and is configured to support a catalytic metal substrate (560). The catalytic substrate (560) may comprise copper, nickel, cobalt, iron, alloys thereof, or combinations thereof, and is positioned to facilitate contact with the precursor vapor stream.

[0170] An exhaust outlet (570) is provided to remove reaction by-products and maintain flow through the reactor. A temperature control system (580) is operatively associated with the heating zone (520) to regulate reactor temperature during graphene growth. The reactor system (500) is configured such that the precursor vapor decomposes at elevated temperature to form graphene or graphenecontaining structures on the catalytic substrate.Figure 5 illustrates a schematic process sequence (600) for graphene formation and subsequent processing. The sequence comprises a substrate cleaning step (610), wherein the catalytic substrate is prepared by removing contaminants and impurities. This is followed by a substrate annealing step (620), wherein the substrate is heated under an inert or reducing atmosphere to improve surface characteristics.

[0171] A precursor introduction step (630) is then carried out, wherein the vaporized precursor is introduced into the reactor in a controlled manner. A graphene growth step (640) follows, during which the precursor vapor undergoes decomposition at elevated temperature and carbon is deposited on the catalytic substrate to form graphene or graphenic layers.

[0172] After deposition, a controlled cooling step (650) is performed under a selected atmosphere to influence graphene formation and stability. An optional graphene transfer step (660) may be carried out to transfer the formed graphene from the catalytic substrate to a target substrate.

[0173] Figure 6 illustrates a schematic diagram of a pulsed injection system (700) configured for delivering the liquid precursor in discrete pulses. The system comprises a pulse controller (710) operatively connected to a metering unit (720), which regulates the quantity of precursor delivered per pulse.

[0174] The metered precursor is supplied to an injector (730), which introduces the liquid into a heated vaporizer (740). The vaporized precursor is then transported through a transfer line (750) to a reactor inlet (760).

[0175] The pulsed injection configuration enables controlled delivery of the precursor, thereby reducing residence time of the liquid precursor within high -temperature zones and minimizing upstream coking, injector fouling, and instability in vaporization.

[0176] Figure 7 illustrates a schematic diagram of a continuous or semi-continuous graphene production system (800). The system comprises a precursor storage tank(810) configured to store conditioned precursor, which is circulated through a conditioned feed loop (820).

[0177] The precursor is delivered to an injection and vaporization module (830), where it is converted into a vapor stream. The vapor is then introduced into a roll-to-roll reactor (840), which is configured to enable continuous processing.

[0178] A moving catalyst foil web (850) passes through the reactor, allowing graphene to be deposited continuously on the substrate surface. Following deposition, the coated substrate is conveyed through a cooling section (860) to stabilize the formed graphene. The processed material is then collected at a product collection station (870). The system (800) enables scalable and continuous production of graphene or graphene-containing materials.

[0179] Figure 8 illustrates a conceptual comparative schematic (900) between untreated biocrude processing (910) and pre-treated biocrude processing (920). In the untreated biocrude processing route (910), the precursor is introduced without sufficient conditioning, which may result in unstable injection, condensation, upstream coking, fouling, and formation of defective or non-uniform carbon structures.

[0180] In contrast, the pre-treated biocrude processing route (920) involves conditioning of the precursor prior to injection, resulting in improved vapor delivery, reduced fouling, reduced coking, and enhanced formation of graphene or graphenic structures. The schematic highlights the advantages of using a conditioned precursor in improving process stability and deposition quality relative to untreated biocrude.

[0181] The following examples are illustrative and, unless expressly stated otherwise, are prophetic examples intended to describe technically credible embodiments of the invention. These examples are not to be construed as limiting.Example 1: Production of Graphene from Fractionated Algal HTL Biocrude on Copper Foil

[0182] Freshwater or marine microalgal biomass slurry having a solids concentration of about 10 wt.% to about 25 wt.% is subjected to hydrothermal liquefaction at a temperature of about 350°C under 3000 psi pressure sufficient to maintain the reaction medium substantially in the liquid phase. The resulting reaction mixture is separated into gaseous products, an aqueous phase, a biocrude phase, and residual solids.

[0183] The recovered biocrude phase is subjected to centrifugation and fine filtration to remove suspended solids and then dewatered. The conditioned biocrude is fractionated by vacuum distillation to isolate an intermediate fraction having lower residue content and improved volatility relative to unfractionated biocrude. The selected fraction is passed through an adsorption polishing bed to reduce catalystpoisoning impurities.

[0184] The polished precursor is introduced into a direct liquid injection system at a flow rate of about 0.02 mL / min to about 1.5 mL / min and vaporized in a chamber maintained at about 250°C to about 500°C. A transfer line is heated to reduce condensation. The vapor is introduced into a CVD reactor containing copper foil previously annealed under argon and hydrogen. The reactor is maintained at about 930°C to about 1020°C. After deposition and controlled cooling, graphene or fewlayer graphene is obtained on the copper foil.

[0185] Example 2: Production of Few-Layer Graphene from Pre-treated Biosynthetic Crude on Nickel

[0186] A biosynthetic crude produced by co-liquefaction of biomass and plastic-containing feedstock is subjected to solids removal, dewatering, adsorption polishing, and optional blending with a lighter compatible fraction. The treated precursor is introduced by pulsed direct liquid injection into a vaporizer and transported to a DLLCVD reactor containing nickel foil under argon and hydrogen. The reactor ismaintained at about 900°C to about 1050°C. The process is operated to produce a few-layer graphene or graphene-rich carbon film.

[0187] Example 3: Sludge-Derived Biocrude with Demetallization and Desalting A sludge-derived biocrude is sequentially treated by settling, centrifugation, fine filtration, desalting, and adsorption-based demetallization. A selected fraction is delivered to a vaporizer maintained at about 250°C to about 500°C and then to a copper or nickel substrate in a reactor maintained at about 900°C to about 1030°C. The treated precursor exhibits lower injector fouling and improved graphenic deposition tendency relative to untreated sludge-derived biocrude.

[0188] Example 4: Comparative Illustrative Example - Untreated Biocrude Versus Pre-treated Biocrude

[0189] A raw biocrude obtained from wet biomass hydrothermal liquefaction is divided into two portions. A first portion is used substantially without pre-treatment other than coarse solids removal. A second portion is subjected to dewatering, fine filtration, adsorption polishing, and fractionation.

[0190] Under otherwise comparable DLI-CVD conditions, the untreated precursor exhibits one or more of unstable injection, nozzle fouling, transfer-line condensation, upstream coking, soot formation, or deposition of defective carbon. By contrast, the pre-treated precursor exhibits improved vapor delivery, lower fouling, and improved graphenic deposition. This example illustrates a preferred embodiment in which conditioning the precursor improves DLI-CVD performance.

[0191] Example 5: Controlled Boiling-Range Fraction Selection

[0192] A raw algal biocrude is fractionated into a light fraction, an intermediate fraction, and a heavy fraction. The intermediate fraction, or a blend enriched in the intermediate fraction, is selected as the precursor for DLI-CVD because it offers more stable injection and vaporization than the heavy fraction and improved sustained carbon delivery relative to the predominantly light fraction.

[0193] 1Example 6: Continuous or Semi-Continuous Production Embodiment A conditioned precursor is stored in a feed vessel and pumped through a filter guard and metering section to an injector. The vaporizer and transfer lines are heat-traced. A moving catalytic substrate web is advanced through a heated reactor zone in which precursor vapor contacts the substrate to form graphene or a graphene-rich film. The coated substrate is then passed through a controlled cooling zone and optionally to a transfer or collection station.

[0194] Without further description, it is believed that one of ordinary skill in the art can, using the preceding description and the illustrative examples, make and utilize the present invention and practice the claimed methods. It should be understood that the foregoing discussion and examples merely present a detailed description of certain preferred embodiments. It will be apparent to those of ordinary skill in the art that various modifications and equivalents can be made without departing from the scope of the invention.

[0195] REFERENCE NUMERAL OF THE INVENTION

[0196] Overall system (100), Feedstock preparation section (110), Hydrothermal liquefaction unit (120), Phase separation unit (130), Biocrude recovery vessel (140), Pretreatment section / train (150), Fractionation unit (160), Conditioned precursor tank (170), Direct liquid injection system (180), Vaporization chamber (190), Heated transfer line (200), CVD graphene reactor (210), Catalyst substrate holder (220), Gas supply manifold (230), Cooling section (240), Graphene transfer station (250)

[0197] Pretreatment system (300), Raw biocrude feed vessel (310), Coarse filtration unit (320), Centrifuge or separator (330), Dewatering stage (340), Desalting stage (350), Adsorption polishing bed (360), Demetallization unit (370), Fractionation column / evaporator (380), Treated precursor reservoir (390)

[0198] DLI and vaporization assembly (400), Precursor reservoir (410), Metering pump (420), Pulse controller (430), Injector nozzle (440), Vaporization chamber (450),Heating jacket (460), Carrier gas inlet (470), Vapor outlet (480), Heated transfer line (490), Graphene deposition reactor system (500)

[0199] Reactor body (510), Heating zone / furnace (520), Precursor vapor inlet (530), Carrier / reducing gas inlet (540), Catalyst substrate holder (550), Catalytic metal substrate (560), Exhaust outlet (570), Temperature control system (580)

[0200] process sequence (600), substrate cleaning step (610), substrate annealing step (620), precursor introduction step (630), graphene growth step (640), cooling step (650), and graphene transfer step (660).

[0201] pulsed injection system (700), pulse controller (710), metering unit (720), injector (730), heated vaporizer (740), transfer line (750), and reactor inlet (760).

[0202] continuous production system (800), precursor storage tank (810), conditioned feed loop (820), injection and vaporization module (830), roll-to-roll reactor (840), moving catalyst foil web (850), cooling section (860), and product collection station (870).

[0203] comparative schematic (900), untreated biocrude processing (910), and pretreated biocrude processing (920).

Claims

ClaimsWe claim1. A method for producing graphenic material, comprising:(a) obtaining biocrude or biosynthetic crude from hydrothermal liquefaction of algal biomass, carbon-rich feedstocks, or combinations thereof;(b) refining said biocrude or biosynthetic crude to remove impurities;(c) injecting the refined biocrude or biosynthetic crude into a vaporization chamber via direct liquid injection;(d) introducing the vaporized biocrude or biosynthetic crude into a chemical vapor deposition reactor containing a metal catalyst substrate; and (e) decomposing the vaporized biocrude or biosynthetic crude at elevated temperature to form graphene, a graphenic film, or a graphenecontaining carbon nanostructure on the substrate.

2. The method as claimed in claim 1, wherein the feedstock for the biocrude or biosynthetic crude comprises microalgae, macroalgae, seaweed, biosolids, municipal solid waste (MSW), agricultural waste, food waste, animal waste, industrial waste, plastic waste, or combinations thereof.

3. The method as claimed in claim 1 or claim 2, wherein the biocrude or biosynthetic crude is refined using distillation, catalytic upgrading, adsorption, or combinations thereof to reduce oxygen, nitrogen, sulfur, or other impurities.

4. The method as claimed in any of claims 1 to 3, wherein the metal catalyst substrate comprises copper, nickel, cobalt, iron, an alloy thereof, or a combination thereof.

5. The method as claimed in any of claims 1 to 4, wherein the vaporization chamber is maintained at a temperature of about 250°C to about 500°C ormore, and the chemical vapor deposition reactor is maintained at a temperature of about 900°C to about 1000°C or more.

6. The method as claimed in any of claims 1 to 5, wherein the graphenic material is selected from monolayer graphene, bilayer graphene, trilayer graphene, few-layer graphene, multilayer graphene, graphene-rich films, graphenic carbon films, and graphene-containing carbon nanostructures.

7. The method as claimed in any of claims 1 to 6, further comprising transferring the graphenic material from the metal catalyst substrate onto a target substrate.

8. The method as claimed in any of claims 1 to 7, wherein the chemical vapor deposition reactor is operated under an inert gas atmosphere, a hydrogeninert gas atmosphere, or a combination thereof.

9. The method as claimed in any of claims 1 to 8, wherein the biocrude or biosynthetic crude is subjected to one or more conditioning operations selected from filtration, dewatering, solids reduction, desalting, demetallization, heteroatom reduction, adsorption treatment, fractionation, solvent adjustment, viscosity adjustment, catalytic upgrading, and combinations thereof prior to direct liquid injection.

10. The method as claimed in claim 9, wherein the biocrude or biosynthetic crude is derived from hydrothermal liquefaction, co-liquefaction, pyrolysis, catalytic depolymerization, thermal conversion, upgrading, or combinations thereof.

11. The method as claimed in claim 9 or claim 10, wherein the conditioning step comprises selecting a fraction having reduced coking tendency and improved suitability for vaporization relative to an unfractionated feed.

12. The method as claimed in any of claims 9 to 11, wherein the direct liquid injection is continuous, pulsed, intermittent, atomized, nebulized, or a combination thereof.

13. The method as claimed in any of claims 9 to 12, wherein the liquid carbon feedstock comprises biosynthetic crude derived from co-processing of biomass and plastic -containing feedstock.

14. The method as claimed in any of claims 9 to 13, wherein a transfer line between the heated vaporization zone and the chemical vapor deposition reactor is heated to reduce condensation and upstream fouling.

15. The method as claimed in any of claims 9 to 14, wherein the precursor is conditioned and introduced under conditions selected to reduce upstream coking relative to an untreated feedstock under otherwise comparable direct liquid injection chemical vapor deposition conditions.

16. The method as claimed in any of claims 9 to 15, wherein the pretreated precursor is delivered at a flow rate of about 0.02 mL / min to about 1.5 mL / min.

17. The method as claimed in any of claims 9 to 16, wherein the precursor comprises a selected intermediate fraction of hydrothermal-liquefaction- derived biocrude or biosynthetic crude.

18. The method as claimed in any of claims 9 to 17, wherein the precursor comprises a demetallized and desalted biocrude or biosynthetic crude fraction.

19. A system for producing graphenic material from biocrude or biosynthetic crude, comprising:a) a hydrothermal liquefaction unit configured to generate biocrude or biosynthetic crude;b) a biocrude refining unit;c) a direct liquid injection system;d) a vaporization unit;e) a chemical vapor deposition reactor with a metal catalyst substrate;andf) a gas handling section configured to supply one or more carrier gases, inert gases, reducing gases, or combinations thereof.

20. The system as claimed in claim 19, wherein the biocrude feedstock is selected from microalgae, macroalgae, seaweed, biosolids, municipal solid waste (MSW), agricultural waste, food waste, animal waste, industrial waste, or combinations thereof.

21. The system as claimed in claim 19 or claim 20, wherein the biosynthetic crude feedstock is selected from microalgae, macroalgae, seaweed, biosolids, municipal solid waste (MSW), agricultural waste, food waste, animal waste, industrial waste, plastic waste, or combinations thereof.

22. The system as claimed in claim 21, wherein the plastic waste comprises polycarbonate, polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polyvinyl chloride, polyamides, mixed plastic wastes, or combinations thereof.

23. The system as claimed in any of claims 19 to 22, wherein the chemical vapor deposition reactor is operated under an inert gas atmosphere, a hydrogeninert gas atmosphere, or a combination thereof.

24. The system as claimed in any of claims 19 to 23, further comprising a renewable power source selected from solar, wind, biomass, hydrogen-based systems, or combinations thereof.

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