BACKGROUND OF THE INVENTION

This invention relates to lignin-based treatment compositions, in particular ligninbased treatment compositions comprising catholyte solutions, and related methods.

A large number of different hydrocarbon treatment applications are found, for example, in the oil and gas industry. A myriad of techniques exist for the separation and recovery of hydrocarbons from various hydrocarbon-containing materials, be they particulate hydrocarbon containing materials or liquid hydrocarbon-containing materials, or the like. In the oil and gas industry, the hydrocarbon containing materials include oil sands, as well as natural gas and oil from subterranean reservoirs.

For instance, the use of analogue ionic liquids for the separation of hydrocarbons from particulate matter has been proposed in United States Patent No. 9,447,329. However, the reagents used are costly and may make the process economically infeasible. SUMMARY OF THE INVENTION

In one aspect of the invention, there is provided a lignin-based treatment composition, for example for treating a hydrocarbon-containing material, the treatment composition comprising:

- lignin; and

- a catholyte solution, the catholyte solution having a concentration of less than 1 .0% and a Redox/ORP value of between about -450 to -950 mV.

In some embodiments, the hydrocarbon-containing material comprises hydrocarbon- containing particulate matter.

In some embodiments, the hydrocarbon-containing material comprises a hydrocarbon-containing liquid.

In some embodiments the treatment composition further comprises at least one isolated strain of bacteria capable of producing at least one biosurfactant, and/or at least one biosurfactant produced from at least one bacteria capable of producing a biosurfactant.

In some embodiments the lignin is technical lignin.

Other aspects and features of the present invention will become apparent, to those ordinarily skilled in the art, upon review of the following description of specific embodiments of the disclosure.

DESCRIPTION OF PREFERRED EMBODIMENTS

The lignin-based treatment compositions comprise a catholyte solution and are provided, for example, for hydrocarbon treatment applications and related methods. In some embodiments, the hydrocarbon-containing material comprises hydrocarbon- containing particulate matter. As used herein, “particulate matter” refers to matter comprising solid particles. In some embodiments, the hydrocarbon-containing particulate matter is relatively free of water. In other embodiments, the hydrocarbon- containing particulate matter may comprise at least a portion of water.

The particulate matter may comprise solid particles of materials found in the ground, including but not limited to sand, clay, soil, silt, rock, solid mineral or metal particles, and the like. In other embodiments, the particulate matter may comprise solid particles associated with processing of hydrocarbons, such as metal particles from drilling or process equipment.

In some embodiments, the hydrocarbon-containing material may comprise particulate matter extracted from a subterranean reservoir. As used herein, “reservoir” refers to any subterranean region, in an earth formation, that includes at least one pool or deposit of hydrocarbons therein.

In some embodiments, the reservoir is an oil sands reservoir. Oil sands, also known as tar sands and bituminous sands, are naturally occurring deposits of viscous oil in loose sands or partially consolidated sandstone. As used herein, “viscous oil” refers to hydrocarbon material having high viscosity and high specific gravity. In some embodiments, viscous oil comprises heavy oil and/or bitumen. Heavy oil may be defined as a hydrocarbon material having a viscosity greater than 100 centipoise (0.1 Pa*s) under reservoir conditions and an API gravity of 20° API or lower. Bitumen may be defined as a hydrocarbon material having a viscosity greater than 10,000 centipoise (10 Pa»s) under reservoir conditions and an API gravity of 10° API or lower.

In some embodiments, the oil sands ore may be extracted by a surface mining process. The term “surface mining” in this context refers to extraction of oil sands ore from an open pit or burrow. Surface mining is used for viscous oil deposits located relatively close to the surface. For example, surface mining operations at the Athabasca oil sands in Alberta, Canada typically involve excavating oil sands ore from a mine pit using hydraulic or electric shovels. The ore is then further processed, including, for example, crushing the ore into smaller particles and mixing the ore with hot or warm water (optionally with caustic soda) to form a slurry that can be conveyed for further processing. Raw or processed oil sands ore or oil sands slurry may be used in the methods described herein.

In other embodiments, the particulate matter may comprise soil or other ground material contaminated with at least one hydrocarbon. For example, the particulate matter may comprise soil and/or sand contaminated due to a pipeline leak of crude oil or processed oil in the form of gasoline, or the like. As another example, the particulate matter may comprise soil and/or sand contaminated with natural gas.

In other embodiments, the hydrocarbon-containing material may comprise a hydrocarbon-containing fluid. In some embodiments, the hydrocarbon-containing fluid comprises a multiphase fluid. As used herein, “multiphase fluid” refers to a fluid comprising more than one phase such as a liquid, solid and/or gas phase. In other embodiments, the hydrocarbon-containing fluid may comprise a hydrocarbon- containing liquid that is relatively free of solid material and/or gas.

In some embodiments, the hydrocarbon-containing fluid may comprise an emulsion. For example, the fluid may comprise an oil-water emulsion such as an oil-in-water emulsion or a water-in-oil emulsion. In some embodiments, the emulsion may further comprise at least a portion of particulate matter. As one example, water-in-oil emulsions may be produced during crude oil recovery due to naturally occurring water in the reservoir. Such emulsions may also comprise at least a portion of entrained sand, clay, or the like.

In some embodiments, the hydrocarbon-containing fluid comprises tailings from an oil recovery operation. Conventional oil sands mining operations separate the bitumen from the sand and clay of the oil sands ore using hot or warm water extraction, which produce large volumes of wastewater (i.e. tailings). The tailings are typically stored in large man-made tailings ponds. Tailings from oil sands surface mining operations may comprise a mixture of residual viscous oil (bitumen), salts, suspended solids, and dissolved salts, organics, and minerals. In other embodiments, the hydrocarbon-containing fluid may comprise drill cuttings from drilling of oil or gas wells. The drill cuttings may comprise solid particulate matter removed from the borehole and brought to the surface in the drilling fluid. The drilling fluid (also called “drilling mud”) may comprise water, a water-based mud (WBM), an oil-based mud (OBM), a synthetic-based mud (SBM) or any other suitable type of mud.

In other embodiments, the hydrocarbon-containing fluid may comprise a liquid contaminated with one or more hydrocarbons. For example, the hydrocarbon- containing liquid may comprise fresh water or seawater contaminated by a crude oil spill, mixtures of oil and water resulting from rinsing of oil tankers or storage facilities, for example.

In other embodiments, the hydrocarbon-containing material may comprise any other suitable material and embodiments are not limited to the specific materials described herein.

As used herein, “lignin” refers to a biopolymer that is found in the secondary cell wall of plants and some algae. Lignin is a complex cross-linked phenolic polymer with high heterogeneity. Typical sources for the lignin include, but are not limited to, softwood, hardwood, and herbaceous plants such as corn stover, bagasse, grass, and straw, for example.

In some embodiments, the lignin comprises technical lignin. As used herein, “technical lignin” refers to lignin that has been isolated from lignocellulosic biomass, for example, as a byproduct of a pulp and paper production or a lignocellulosic biorefinery. Technical lignins may have a modified structure compared to native lignin and may contain impurities depending on the extraction process. In some embodiments, the technical lignin comprises at least one of Kraft lignin, lignosulfonates, soda lignin, organosolv lignin, steam-explosion lignin, and enzymatic hydrolysis lignin. In other embodiments, the technical lignin may comprise any other form of technical lignin. In embodiments where the lignin comprises lignosulfonates, the lignosulfonates may be in the form of a salt including, for example, sodium lignosulfonate, calcium lignosulfonate, or ammonium lignosulfonate.

In other embodiments, the technical lignin is in the form of unhydrolyzed Kraft black liquor. Black liquor is a byproduct of the Kraft process and may contain not only lignin but hemicellulose, inorganic chemicals used in the pulping process, and other impurities. In other embodiments, the technical lignin is in the form of “brown liquor” (also referred to as red liquor, thick liquor or sulfite liquor), which refers to the spent liquor of the sulfite process. In other embodiments, the technical lignin may be in the form of any other spent cooking liquor of a pulping process or any other suitable ligninbased byproduct.

In other embodiments, the lignin may be synthetic lignin or any other suitable type of lignin.

In some embodiments, the lignin is hydrolyzed. As used herein, “hydrolyze” refers to using acid or base hydrolysis at least partially to separate lignin from the polysaccharide content of the lignocellulosic biomass. For example, where the lignin is in the form of black liquor, carbon dioxide may be used to precipitate Kraft lignin from the black liquor and then the Kraft lignin may be neutralized with sodium hydroxide.

In some embodiments, the lignin is in an aqueous suspension. As used herein, an “aqueous suspension” of lignin refers to solid particles of lignin suspended, dispersed, and/or dissolved in a solvent that at least partially comprises water. In some embodiments, the solvent comprises substantially all water. In other embodiments, the solvent may comprise a combination of water and any other suitable solvent.

In some embodiments, the aqueous suspension of lignin may have a solids content of about 10% to about 90%, or about 25% to about 75%, or about 30% to about 60%, or about 33% to about 55%. In some embodiments, the aqueous suspension of lignin may have a solids content of about 10% or above, or of about 25% or above, or of about 30% or above, or of about 33% or above. In some embodiments, the aqueous suspension of lignin may have a solids content of about 90% or below, or of about 75% or below, or of about 60% or below, or of about 55% or below. In some embodiments, the aqueous suspension has a solids content of about 46%. A solids content of about 33% to about 55% may allow the composition to be flowable, which may be preferred for some applications. In other applications, the composition may be used as a slurry and the solids content may be as high as about 85% to about 90%.

In some embodiments, the lignin comprises at least one of lignin nanoparticles and lignin microparticles. As used herein, “nanoparticle” refers to a particle in the nanometer size range, for example, between about 1 nm and about 100nm, and “microparticle” refers to a particle in the micrometer size range, for example, between about 100 nm and about 1000 pm (1 mm). In some preferred embodiments, the lignin particles have a size of about 200nm or less, or about 100nm or less. In some preferred embodiments, at least about 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90% of the lignin particles are nanoparticles having a size of about 100nm or less.

The lignin nanoparticles and/or microparticles can be produced by any suitable method. For example, the lignin nanoparticles and/or microparticles can be produced using at least one of: solvent shifting; pH shifting; cross-linking polymerization; mechanical treatment; ice-segregation; template based synthesis; aerosol processing; electro spinning; and carbon dioxide (CO2) antisolvent treatment. Such methods are described in Beisl et al. “Lignin from Micro- to Nanosize: Production Methods” Int. J. Mol. Sci. 2017; 18: 1244, incorporated herein by reference in its entirety.

In some preferred embodiments, lignin nanoparticles are produced using a pH shifting method, for example, as disclosed in Beisl et al. Briefly, the starting lignin material may be dissolved in a basic solution (e.g. an aqueous NaOH solution at pH 12) and the pH of the solution may be gradually decreased by addition of acid (e.g. HNO3) to precipitate lignin nanoparticles. The solution may then be neutralized (e.g. by addition of NaOH) to re-suspend the nanoparticles. The resulting particles may have a size of about 200 nm or less, or about 100 nm or less. In other embodiments, the lignin nanoparticles may be produced by any other suitable method.

By providing the lignin in the form of lignin nanoparticles and/or microparticles, the surface area of the lignin is increased, thereby also increasing the negative force around each particle. In addition, lignin nanoparticles and/or microparticles may have improved solubility in water. Conventional lignins are typically only soluble in water at alkaline pH; however, nanoparticles and/or microparticles may be soluble in approximately neutral water (Beisl et al.), which may be preferred for some applications.

In some embodiments, where the lignin comprises an aqueous suspension of lignin nanoparticles, the zeta potential value of the suspension may be about -5 to about -80 mV. In some embodiments, the specific gravity of the aqueous suspension of lignin nanoparticles is between about 1.286 to about 1.7 SG.

The lignin-based treatment compositions of the invention further comprise catholyte solutions. As used herein, “catholyte solution” is an activated reducing agent produced in an electrochemical reaction that is part of the electrolyte portion adjacent the cathode of an electrochemical cell reactor. The metastable catholyte solution is chemically similar to hydrated caustic soda (sodium hydroxide). However, being produced in an electrochemical cell reactor, the solution of the invention has a higher order reduction (Redox/ORP) value in the order of -450 to -950 mV, preferably in the order of -900 to -950 mV, the catholyte solutions of the invention being significantly more reactive in low concentrations. The electrolytic reaction and membrane also yield excess hydroxide in the solution that may result in beneficial downstream blending reactions. It can be produced, for instance, from a 0.05% - 1 % salt brine (NaCI or KCI), has a pH in the range of 1 1.5 to 13.0, and can be used to produce an electrolyte solution, for example NaOH or KOH, with a concentration of less than 1.0%, typically about 0.05% to 0.6%. As would be evident to a person skilled in the art, the catholyte solution of the invention is distinguishable from conventional sodium hydroxide solutions. Additionally, it avoids a number of disadvantages that are associated with conventional sodium hydroxide solutions. Conventional sodium hydroxide solutions often require heating in their manufacture and/or use, whereas this is not required of the catholyte solutions of the invention at similar concentrations. In addition, the handling of concentrated lye in manufacturing sodium hydroxide is a hazardous process, and the materials are highly corrosive. Finally, given the nature of the electrochemical cell reactor, the conversion of salt to catholyte solution is highly efficient from a purity, energy and raw to final values perspective. In other words, the conversion ratios are very good and energy yield is high.

It is also envisaged that a blended NaOH/KOH solution can be produced, made possible by the electrochemical process. KOH in turn provides an environmentally friendly alternative to a NaOH catholyte solution.

A further advantage is that any free Na ⁺ or K ⁺ ions, for example, will be expunged by the bacteria utilized in embodiments of the invention.

The treatment compositions of the invention can comprise from about 1% to about 75% by volume of the catholyte solution.

In some embodiments, the composition further comprises at least one isolated strain of bacteria capable of biosurfactant production and/or at least one biosurfactant produced from at least one isolated strain of bacteria capable of producing a biosurfactant.

As used herein, “isolated” or “isolate”, when used in reference to a strain of bacteria, refers to bacteria that have been separated from their natural environment. In some embodiments, the isolated strain or isolate is a biologically pure culture of a specific strain of bacteria. As used herein, “biologically pure” refers to a culture that is substantially free of other organisms. As used herein, “biosurfactant” refers to compounds that are produced at the bacterial cell surface and/or secreted from the bacterial cell and function to reduce surface tension and/or interfacial tension. Non-limiting examples of biosurfactants include lipopeptides, surfactin, glycolipids, rhamnolipids, methyl rhamnolipids, and viscosin, for example. The isolated strain may be capable of producing one or more types of biosurfactant.

In some embodiments, the isolated strain may produce one or more additional active compounds. For example, the isolated strain may produce a biopolymer, solvent, acid, exopolysaccharide, and the like.

In some embodiments, the at least one isolated strain of bacteria comprises a strain of Bacillus. In other embodiments, the at least one isolated strain comprises a strain of bacteria capable of biosurfactant production and that is non-pathogenic. Nonlimiting examples of suitable strains are listed in Satpute et al. “Methods for investigating biosurfactants and bioemulsifers: a review” Critical Reviews in Biotechnology, 2010, 1 -18. For example, the at least one isolated strain of Bacillus may be Bacillus amyloliquefaciens, Bacillus licheniformis, Bacillus pumilus, Bacillus subtilis, or combinations thereof.

In some embodiments, the pH of the composition may be selected or adjusted to provide a suitable pH for the isolated strain(s). In some embodiments, the composition may further comprise one or more nutrients to support growth of the bacteria such as, for example, acetate, one or more vitamins, and the like.

In some embodiments, the isolated strain is in a viable form. For example, in some embodiments, the isolated strain may be in the form of a liquid suspension. In some embodiments, the isolated strain may be incubated for a suitable period of time prior to incorporation into the composition such that at least a portion of biosurfactant(s) is/are secreted into the bacterial suspension and therefore can be incorporated into the composition. For example, the bacteria can be incubated/fermented for between about one day and about six months or longer. The isolated strain may be incubated in the presence of a nutrient source and under suitable conditions (e.g. temperature, agitation, etc.) to produce the biosurfactant(s).

In other embodiments, the isolated strain may be in a lyophilized (freeze-dried) form. In some embodiments, the freeze-dried form comprises freeze-dried spores.

In some embodiments, where the isolated strain is in the form of a liquid suspension or in a freeze-dried form, the composition may comprise approximately 40 billion CFU (colony forming units) and may be combined with at least about 1 g of lignin and up to several tons of lignin.

In other embodiments, the isolated strain may be in an inviable form. For example, the isolated strain may be in the form of heat-killed cells or a cell lysate. In these embodiments, the bacteria of the isolated strain may be incubated for a suitable period of time prior to loss of viability (e.g. heat killing or lysis) such that a sufficient quantity of biosurfactant(s) is/are secreted into the bacterial suspension for incorporation into the composition. For example, the bacteria may be incubated for at least one week prior to loss of viability.

In other embodiments, a liquid suspension of bacteria may be incubated to produce the biosurfactant(s) and a supernatant containing the biosurfactant(s) may be separated from the bacterial cells and used in the composition.

Without being limited by theory, it is believed that the combination of lignin and the biosurfactant produced by the isolated strain act to mimic the natural habitat of the biosurfactant producing strains. The lignin may function as a growth substrate that contains required nutrients (carbon and fructose) to support growth of the bacteria, with the exception of additional acetate and metallic vitamins, which may be added to the composition as needed.

In some embodiments, the treatment composition further comprises at least one of a carboxylic acid or a salt or ester thereof. In some embodiments, the carboxylic acid is a di-carboxylic acid or a salt or ester thereof. The carboxylic acid or salt/ester thereof may function as a solvent, for example, by facilitating formation of a stable emulsion of the various components of the composition. In some embodiments, the composition comprises a carboxylic acid ester. In some embodiments, the carboxylic acid ester comprises a methyl ester or a butyl ester. In some embodiments, the butyl esters are produced by biochemical metathesis. In some embodiments, the butyl ester comprises n-Butyl 4-oxopentanoate. In some embodiments, the methyl ester comprises unsaturated C10 or C12 methyl ester. In some embodiments, the methyl ester comprises methyl 9-decenoate or methyl 9-dodecenoate. In some embodiments, the methyl ester is produced from a plant oil feedstock.

In some embodiments, the composition further comprises carbon black. The carbon black may be electroconductive carbon black and the carbon black may function to increase the conductivity of the composition. In some embodiments, the carbon black may be conductive, superconductive, extraconductive or ultraconductive carbon black. In some embodiments, the carbon black may be in the form of carbon black beads, microparticles, and/or nanoparticles. For example, the carbon black may comprise Printex™ XE2 B Beads from Orion Engineered Carbons™ . In some embodiments, the composition may comprise about 0.5% to about 10% carbon black by volume. In some embodiments, addition of carbon black may increase the negative zeta potential of the composition thereby increasing its electrical stability. In other embodiments, the composition may comprise any other highly conductive microparticle and/or nanoparticle.

In some embodiments, the composition may comprise about about 1 % to about 20%, or about 1 % to 10% of di-carboxylic acid and/or butyl esters by volume.

In some embodiments, the composition is gasified with a gas. As used herein, “gasified” refers to introduction of a gas into the composition such that bubbles of the gas are suspended therein. The term “aerated” refers to gasifying with air or oxygen. The gas may be selected based on the aerobic or anaerobic nature of the isolated strain(s) incorporated into the composition. In some embodiments, the gas at least partially comprises oxygen. For example, the gas may be air or relatively pure oxygen. In some embodiments, the gas may at least partially comprise carbon dioxide and/or nitrogen. Gasification may function to provide oxygen and/or other suitable gasses directly or in close proximity to the bacterial cells of the isolated strain. Gasification may promote proliferation of the bacterial cells and allow the composition to be used or stored for an extended period of time. In some embodiments, the aerated composition may have a half-life of about 20 to 30 days.

In some embodiments, the composition is gasified with nanobubbles and/or microbubbles of the gas. As used herein, “nanobubble” refers to bubbles in the nanometer range and “microbubble” refers to bubbles in the micrometer range. The nanobubbles and/or microbubbles may be introduced into the composition by any suitable means including, for example, a micro- or nanobubble nozzle or a venturi tube.

The compositions disclosed herein may be useful for various treatment applications, including separation applications in the recovery and/or processing of hydrocarbons including, for example, hydrocarbon separation, demulsification of oil-in-water emulsions, and separation from particulate matter. Embodiments of the compositions may be used in ambient temperatures (for example, between about 2°C and about 25°C) and function via a rotational barrier repulsion mechanism.

In some embodiments, the composition may comprise any other suitable components. For example, in some embodiments, the composition may further comprise at least one nutrient source for the live bacteria of the isolated strain.

Therefore, in some embodiments, a relatively non-toxic, inert, and sustainable composition is provided for hydrocarbon treatment. The composition may also be relatively low cost as lignin is a waste product of pulp and paper operations that is typically discarded.

In some embodiments, a hydrocarbon-containing material is contacted with the treatment composition. The term “contact” in this context may refer to any means by which the composition may be brought into contact with the hydrocarbon-containing material. In some embodiments, the composition may be introduced into the hydrocarbon-containing material. In other embodiments, the hydrocarbon-containing material may be introduced into the composition. In some embodiments, the composition and hydrocarbon-containing material may be combined, for example, by mixing, blending, homogenizing, infusing, or any other suitable means.

In some embodiments, where the hydrocarbon-containing material comprises a hydrocarbon-containing fluid, contacting the fluid with the composition may comprise flowing the fluid through the composition. In some embodiments, the composition may be immobilized on a solid support. As one example, the composition may be coated onto an interior surface of a pipe or other fluid conduit and the hydrocarbon-containing fluid may be flowed through the pipe to contact the composition. In some embodiments, the pipe may have a high surface area to increase the contact of the fluid with the composition.

As another example, the composition may be associated with a filtration medium and the fluid may be flowed through the filtration medium. In some embodiments, the composition may be embedded in or bound to the filtration medium. In other embodiments, the composition may only be loosely associated with the filtration medium, for example, as a mechanical mixture. Non-limiting examples of filtration media include biochar, zeolites, sand, diatomaceous earth, and the like. In some embodiments, the filtration medium may be held in a solid support, such as a separation column or a packed bed, for example. The fluid may then be passed through the filtration medium in the solid support at a suitable flow rate to facilitate contact between the fluid and the composition. In other embodiments, the filtration medium and the fluid may be combined in a suitable vessel and, after a suitable period of time, the filtration medium may be separated from the remaining fluid. The filtration medium may be separated from the fluid by precipitation, pressing, screening, centrifugation, or any other suitable separation method.

In some embodiments, the material may briefly be contacted with the composition. For example, a fluid may be flowed through the composition at a relatively high rate. In other embodiments, the material may be contacted with the composition for a desired residency time. For example, the residency time may be at least an hour, a day, or a week. Longer residency times may allow the bacteria in the composition to proliferate and secrete biosurfactants, allowing for greater biosurfactant production and greater contact between the biosurfactants and the hydrocarbon-containing material.

In some embodiments, the material may be contacted with the composition at relatively low temperatures such as below 100°C, below 50°C, below 25°C, or lower. In some embodiments, the temperature may be the ambient temperature i.e. the temperature in the surrounding environment without the addition of heat. In other embodiments, the temperature may be raised, for example, to lower the viscosity of the hydrocarbon-containing material. The temperature can be raised by electric heating, electromagnetic heating, microwave heating or any other suitable heating means.

In some embodiments, the ratio of the composition to the hydrocarbon-containing material is about 50:1. In some embodiments, the composition comprises between about 1 wt.% and about 50 wt.% of the combined composition and hydrocarbon- containing material mixture. As one example, about 98 wt.% hydrocarbon-containing material may be combined with about 2 wt.% of the composition. In other embodiments, any other suitable ratio may be used.

In some embodiments, the hydrocarbon-containing material may be analyzed prior to contacting the material with the composition. For example, the material may be analyzed to determine the hydrocarbon content, water content, solids content, pH, electrical conductivity, or the like. Analysis of the material may be used to determine a suitable dosage of the composition and/or if further processing of the material is desirable. For example, the dosage protocol may be defined by IFT (interfacial tension), shear angle, and kinetic separate laboratory tests.

In some embodiments, the material may be processed prior to contacting the material with the composition. As one example, the water content of the material may be adjusted, for example, by adding water or removing water (e.g. by evaporation). As another example, the material may be concentrated, for example, by centrifugation. As another example, hydrocarbon-containing particulate matter containing relatively large particles may be crushed into a finer form.

In some embodiments, the composition and material are mixed in a mixing device or may be mixed manually, for example, by stirring or agitation.

In some embodiments, a liquid is introduced into the mixture to form a slurry. In some embodiments, the liquid may comprise water. The water may comprise, for example, fresh water, salt water, brine, produced ground water, or any other suitable type of water. In other embodiments, the liquid may comprise another suitable solvent.

In some embodiments, the liquid is added to the mixture. In other embodiments, the mixture is added to the liquid. In some embodiments, the liquid and the mixture may be mixed together, using any appropriate mixing techniques.

In some embodiments, (where the material comprises little to no native water), between about 25% to about 100% by weight of liquid may be added to the mixture. In some embodiments, about 50% by weight of liquid may be added to the mixture. In other embodiments, any other suitable amount of liquid may be used.

Combining the material with the composition prior to introducing the liquid may avoid diluting the composition in the liquid, thereby maximizing the contact between the material and the lignin and catholyte solution of the composition. However, alternative orders of steps are also possible. For example, in some embodiments, the liquid may be introduced prior to mixing the composition with the material. Alternatively, the liquid may be added to the composition itself and the composition/liquid mixture may be mixed with the hydrocarbon-containing material. Moreover, in embodiments in which the hydrocarbon-containing material already has a relatively high water content, no further addition of liquid may be needed.

In some embodiments, the slurry may be allowed to separate into at least two phases. In some embodiments, the slurry may be allowed to separate under the force of gravity. In some embodiments, the slurry may be separated in a separation vessel. In some embodiments, separation may be facilitated by stirring, agitation, etc. In other embodiments, separation of the slurry may be facilitated by centrifugation. In other embodiments, separation of the slurry may be facilitated by ultrasonic separation techniques.

The two or more phases may comprise, for example, a liquid hydrocarbon (oil) phase, an aqueous phase, and a solid particulate phase. The lignin and bacteria of the composition is expected to move into the aqueous phase. Some hydrocarbon- containing materials may also result in an emulsion phase, gas phase, and the like. In some embodiments, the two or more phases exist as two or more relatively distinct layers. The two or more layers may typically be separated by a boundary, although the layers could also exist without a distinct boundary.

As one example, the two or more layers may comprise an upper layer, a middle layer, and a lower layer. The upper layer may primarily comprise hydrocarbon, the middle layer may primarily comprise water, and the lower layer may primarily comprise particulate matter. This arrangement may be produced when the density of the hydrocarbon is lower than that of water, which is expected for most of the hydrocarbon-containing materials described above. However, if the density of the hydrocarbon is higher than that of water, the upper layer may primarily comprise water and the middle layer may primarily comprise hydrocarbon.

In other embodiments, the two or more phases may be both present without forming layers. For example, droplets of hydrocarbon (oil) may be present in an aqueous phase.

In some embodiments, the method further comprises at least partially removing one or more of the separated phases following the steps. The term “removing” in this context may refer to isolating, separating, segregating, or sequestering matter from one phase from matter of another phase. For example, at least a portion of the hydrocarbons in the upper layer may be skimmed from top of the separated mixture. As another example, at least a portion of the particulate matter may be withdrawn from the bottom of the separated mixture. In some embodiments, the separated phases may be removed in two or more stages. For example, one or more of the separated phases may be at least partially removed from the mixture and the remainder of the mixture may undergo a secondary separation step. The secondary separation step may comprise, for example, further gravity separation, decantation, distillation, evaporation, centrifugation, or any other suitable separation technique.

In some embodiments, after at least partially removing one or more of the separated phases, the mixture may be allowed to separate again. In some embodiments, the mixture may first be agitated or stirred to re-combine the separated phases and then allowed to separate again.

In some embodiments, the removed matter may be subjected to further processing, use, and/or disposal. Preferably, the hydrocarbon removed from the mixture may be used as a commercial hydrocarbon product such as bitumen, heavy fuel oil, feedstock for refining, or the like.

In some embodiments, the particulate matter may be disposed (e.g. returned to the environment) or used for other purposes. In some embodiments, the particulate matter may be cleaned prior to disposal or use. The particulate matter may be cleaned by any suitable technique including, for example, water washing and/or microbial degradation.

Similarly, the water may be disposed or used. In some embodiments, the water may be cleaned prior to disposal or use. The water may be cleaned by filtration, microbial degradation, or any other suitable technique. In some embodiments, the water may be re-used. In other embodiments, the water may be combined with the recovered hydrocarbons to lower their viscosity and/or to transfer the recovered hydrocarbons downstream (e.g. to transfer the recovered hydrocarbons by pipeline to an oil refinery). In some embodiments, at least a portion of the lignin and/or the bacteria of the isolated strain(s) may be recovered from the water for re-use or disposal. Therefore, the treatment compositions may allow for separation of at least a portion of hydrocarbons from a hydrocarbon-containing material without the use of toxic, and potentially expensive, chemicals. As the lignin/bacteria of the composition automatically move into the aqueous phase, the rheology of the hydrocarbons is not altered.

Various modifications besides those already described are possible without departing from the concepts disclosed herein. Moreover, in interpreting the disclosure, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms "comprises" and "comprising" should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced.

Although particular embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the disclosure. The terms and expressions used in the preceding specification have been used herein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described or portions thereof.