Delignification of railroad ties and recovery of breakdown products

Abstract

A method of converting railroad ties into cellulose for use in fermentation processes; wherein said method comprising the steps of: providing a railroad tie contaminated with at least one compound selected from the group consisting of: creosote; cresol; and a tar product; processing the railroad tie into processed particles of a size ranging of up to 6 inches; providing an acidic composition having a pH of less than 1; providing an alcohol selected from the group consisting of C1-C6 linear alcohol; C3-C6 branched alcohol and mixtures thereof; exposing said processed particles to said acidic composition and said alcohol for a period of time sufficient to delignify said processed particles and yield a contaminated cellulose portion comprising at least one contaminant selected from the group consisting of: creosote; a creosote degradation product; a cresol degradation product; a tar-derivative product; a tar-derivative degradation product; and a liquid portion comprising lignin; lignin depolymerization products; creosote degradation products; cresol degradation products; removing said liquid portion; washing the contaminated cellulose portion with an organic solvent thereby obtaining a washed cellulose separating said washed cellulose from said organic solvent; recovering said washed cellulose portion, wherein said washed cellulose portion contains less than 50% of the initial content of creosote, cresol, and / or a tar product; wherein said obtained cellulose contains amounts of said at least one contaminant which do not prevent cellulose fermentation into a high value added product.

Description

[0001] DELIGNIFICATION OF RAILROAD TIES AND RECOVERY OF BREAKDOWN PRODUCTS

[0002] FIELD OF THE INVENTION

[0003] The present invention is directed to a method of treating creosote waste products, such as railroad ties, to recover usable cellulose fibers and various creosote degradation products resulting from such method.

[0004] BACKGROUND OF THE INVENTION

[0005] Railroad ties are hardwood materials soaked in coal / wood tar as a treatment to prevent degradation of the wood in the environment by preventing the activity of insects and microbes; most notably, brown / white rot fungus. The treatment with coal or wood tar creosote provides the wood with a high concentration of polycyclic aromatic hydrocarbons, phenols, and cresols to accomplish this antimicrobial activity.

[0006] Creosote has been used as a heavy-duty wood preservative for railway ties, bridge timbers, pilings, and large-sized lumber for decades. Creosote contains a mixture of tens if not hundreds of compounds. One of the main group of compounds found in coal-tar creosote are polycyclic aromatic hydrocarbons (PAHs).

[0007] Creosote waste products are wood materials treated with creosote that have since been removed from service and are being stored until final disposal, such products include but are not limited to used railway ties, utility poles, and the like. Used railway ties form the largest creosote waste products (by volume) in Canada. Each year, millions of railway ties are decommissioned which contain tens of millions of kilograms of creosote. Despite this, it has been estimated that only 10 % of railway ties removed each year become waste. However, the waste, in terms of creosote mass still accounts for over a million kilogram of creosote in discarded railway ties.

[0008] Creosote refers to a mixture of hydrocarbons which can comprise more than 300 compounds. It is widely understood that there are five major classes of compounds in coal-tar creosote: aromatic hydrocarbons including PAHs, alkylated PAHs, benzene, toluene, and xylene (PAHs can constitute up to 90% of creosote); phenolics including phenols, cresols, xylenols, and naphthols (1 to 3% of creosote); nitrogen-containing heterocycles including pyridines, quinolines, acridines, indolines, carbazoles (1 to 3% of creosote); sulphur-containing heterocycles including benzothiophenes ( 1 to 3% of creosote); and oxygencontaining heterocycles including dibenzofurans (5 to 7.5% of creosote) (source: U.S. EPA, 1987). Creosote has a higher density than water and it is insoluble in such but soluble in many organic solvents, including oil and diesel fuel.

[0009] Post-use of railroad ties involved the burning thereof by railway companies under permits from provincial environment authorities. However, it is not clear what happens to the portion of ties which are not burned. It is believed that a portion of those are simply sent to landfills. The burning of railroad ties constitutes a damaging practice for the environment as it releases not only carbon dioxide but also a number of creosote degradation products into the atmosphere. Landfdled ties fare not much better as it has been determined that creosote can leach into the environment from creosote-contaminated sites and that large amounts of waste creosote have been discovered in soil, groundwater, and in some cases, even in surface waters. Such leaching can result in damaging effects to the health of the ecosystem and of the wildlife nearby such storage sites.

[0010] Similar concerns exist with respect to marine pilings and utility poles removed from service, do not represent a significant source of creosote waste products compared to the volume of creosote waste products from discarded railway ties.

[0011] There are no known methods to recover the creosote from such discarded materials and the current practices to handle such discarded materials are deleterious to the environment and consist of a waste of potentially useful materials. Extensive studies have been conducted which support the potential environmental damage caused by the storage of discarded railroad ties. The studies have indicated that leaching in to the environment, including soil and groundwater, is commonplace and results in substantial detrimental effect to the fauna.

[0012] In light of the state of the art, there is a pressing need for a method which can recover materials such as cellulose and creosote derivatives (or degradation products) from creosote impregnated woody materials in order to avoid improper handling and disposal of such post-use discarded woody materials.

[0013] SUMMARY OF THE INVENTION

[0014] According to another aspect of the present invention, there is provided a method of converting railroad ties into cellulose for use in a fermentation process; wherein said method comprising the steps of: providing a railroad tie contaminated with at least one compound selected from the group consisting of: creosote; cresol; and a tar product; processing the railroad tie into processed particles of a size ranging of up to 6 inches; providing an acidic composition having a pH of less than 1, said acidic composition selected from the group consisting of: composition A; composition B; composition C; composition D; composition E; composition F; composition G; composition H; composition I; and composition J; wherein said composition A comprises: o sulfuric acid; o a compound comprising an amine moiety and a sulfonic acid moiety; and o a peroxide; and wherein sulfuric acid, said compound comprising an amine moiety and a sulfonic acid moiety and said peroxide are present in a molar ratio of no less than 1: 1:1; wherein said composition B comprises: o sulfuric acid; o a compound comprising an amine moiety; o a compound comprising a sulfonic acid moiety; and o a peroxide; wherein sulfuric acid and said a compound comprising an amine moiety and said compound comprising a sulfonic acid moiety are present in a molar ratio of no less than 1:1: 1; wherein said composition C comprises: o an alkylsulfonic acid; and o a peroxide; wherein said alkylsulfonic acid and said peroxide are present in a molar ratio of no less than 1: 1; wherein said composition D comprises: o sulfuric acid; o a heterocyclic compound; and o a peroxide; and wherein sulfuric acid and said a heterocyclic compound; are present in a molar ratio of no less than 1: 1; wherein said composition E comprises: o sulfuric acid; o a modifying agent comprising a compound containing an amine group; and o a peroxide; and wherein sulfuric acid and said compound containing an amine group; are present in a molar ratio of no less than 1: 1; wherein said composition F comprises: o sulfuric acid; o a modifying agent comprising an alkane sulfonic acid and o a peroxide; and wherein sulfuric acid and said alkanesulfonic acid are present in a molar ratio of no less than 1: 1; wherein said composition G comprises: o sulfuric acid; o a substituted aromatic compound; and o a peroxide; and wherein sulfuric acid and said substituted aromatic compound; are present in a molar ratio of no less than 1: 1; wherein said composition H comprises: o sulfuric acid; o a modifying agent comprising an arylsulfonic acid; o a peroxide; and o optionally, a compound containing an amine group ; wherein sulfuric acid and said a arylsulfonic acid; are present in a molar ratio of no less than 1: 1; wherein said composition I comprises: o sulfuric acid; o a heterocyclic compound; o an alkanesulfonic acid and o a peroxide; and wherein sulfuric acid and said a heterocyclic compound; are present in a molar ratio of no less than 1: 1; wherein said composition J comprises: o sulfuric acid; o a carbonyl-containing nitrogenous base compound; and o a peroxide; and wherein sulfuric acid and said a carbonyl-containing nitrogenous base compound; are present in a molar ratio of no less than 1: 1; providing an alcohol selected from the group consisting of Ci-Ce linear alcohol; C’s-C,, branched alcohol and mixtures thereof; exposing said processed particles to said acidic composition and said alcohol for a period of time sufficient to delignify said processed particles and yield a contaminated cellulose portion comprising at least one contaminant selected from the group consisting of: creosote; a creosote degradation product; a cresol degradation product; a tar-derivative product; a tar-derivative degradation product; and a liquid portion comprising lignin; lignin depolymerization products; creosote degradation products; cresol degradation products; removing said liquid portion; washing the contaminated cellulose portion with an organic solvent thereby obtaining a washed cellulose; separating said washed cellulose from said organic solvent; recovering said washed cellulose portion, wherein said washed cellulose portion contains less than 50% of the initial content of creosote, cresol, and / or a tar product; wherein said obtained cellulose contains amounts of said at least one contaminant which do not prevent cellulose fermentation into bioethanol.

[0015] According to another aspect of the present invention, there is provided a method of converting railroad ties into cellulose for use in fermentation processes wherein the organic solvent used to wash the contaminated cellulose portion is miscible in water. Preferably, said organic solvent used to wash the contaminated cellulose portion is an alcohol. More preferably, said organic solvent used to wash the contaminated cellulose portion is selected from the group comprising of: methanol, ethanol, propanol, isopropanol, and butanol.

[0016] According to another aspect of the present invention, there is provided a method of converting railroad ties into cellulose for use in fermentation processes further comprising a step wherein said washed cellulose portion is washed with water.

[0017] According to another aspect of the present invention, there is provided a method of converting railroad ties into cellulose for use in fermentation processes further comprising a step wherein said washed cellulose portion is neutralized to a pH ranging from 4 to 9. Preferably, said neutralization step is carried out to a pH between 5 and 8. More preferably, said neutralization step is carried out to a pH between 6 and 7.

[0018] Preferably, said creosote degradation product is selected from the group consisting of: uncondensed polycylic aromatic hydrocarbons, small chain acids and diacids. Preferably, said cresol degradation product is selected from the group consisting of: small chain acids and diacids. Preferably, a tar-derivative degradation product is selected from the group consisting of: polycyclic aromatic hydrocarbons.

[0019] According to another aspect of the present invention, there is provided a method for controlled delignification of lignocellulosic feedstock and degradation of creosote compounds, wherein said method can also result in the generation of cellulose for use in fermentation into a value-added product, wherein said method comprises the steps of: providing a railroad tie contaminated with at least one compound selected from the group consisting of: creosote; cresol; and a tar product; processing said railroad tie into processed particles of a size ranging of up to 6 inches; providing a reactive phase of pH less than 1, said reactive phase comprising: o water; and o an acidic composition having apH of less than 1, said acidic composition selected from the group consisting of: composition A; composition B; composition C; composition D; composition E; composition F; composition G; composition H; composition I; and composition J; wherein said composition A comprises: o sulfuric acid; o a compound comprising an amine moiety and a sulfonic acid moiety; and o a peroxide; and wherein sulfuric acid, said compound comprising an amine moiety and a sulfonic acid moiety and said peroxide are present in a molar ratio of no less than 1: 1:1; wherein said composition B comprises: o sulfuric acid; o a compound comprising an amine moiety; o a compound comprising a sulfonic acid moiety; and o a peroxide; wherein sulfuric acid and said a compound comprising an amine moiety and said compound comprising a sulfonic acid moiety are present in a molar ratio of no less than 1:1: 1; wherein said composition C comprises: o an alkylsulfonic acid; and o a peroxide; wherein said alkylsulfonic acid and said peroxide are present in a molar ratio of no less than 1: 1; wherein said composition D comprises: o sulfuric acid; o a heterocyclic compound; and o a peroxide; and wherein sulfuric acid and said a heterocyclic compound; are present in a molar ratio of no less than 1: 1; wherein said composition E comprises: o sulfuric acid; o a modifying agent comprising a compound containing an amine group; and o a peroxide; and wherein sulfuric acid and said compound containing an amine group; are present in a molar ratio of no less than 1: 1; wherein said composition F comprises: o sulfuric acid; o a modifying agent comprising an alkane sulfonic acid and o a peroxide; and wherein sulfuric acid and said alkanesulfonic acid are present in a molar ratio of no less than 1: 1; wherein said composition G comprises: o sulfuric acid; o a substituted aromatic compound; and o a peroxide; and wherein sulfuric acid and said substituted aromatic compound; are present in a molar ratio of no less than 1: 1; wherein said composition H comprises: o sulfuric acid; o a modifying agent comprising an arylsulfonic acid; o a peroxide; and o optionally, a compound containing an amine group ; wherein sulfuric acid and said a arylsulfonic acid; are present in a molar ratio of no less than 1: 1; wherein said composition I comprises: o sulfuric acid; o a heterocyclic compound; o an alkanesulfonic acid and o a peroxide; and wherein sulfuric acid and said a heterocyclic compound; are present in a molar ratio of no less than 1: 1; wherein said composition J comprises: o sulfuric acid; o a carbonyl-containing nitrogenous base compound; and o a peroxide; and wherein sulfuric acid and said a carbonyl-containing nitrogenous base compound; are present in a molar ratio of no less than 1: 1; providing an alcohol selected from the group consisting of Ci-Ce linear alcohol; C’s-C,, branched alcohol and mixtures thereof; providing a holding phase, said holding phase comprising an organic solvent which does not react with the aqueous acidic composition; combining said reactive phase and holding phase to form a reaction mixture; exposing said processed particles to said acidic composition for a period of time sufficient to delignify said processed particles and yield a contaminated cellulose portion comprising at least one contaminant selected from the group consisting of: creosote; a creosote degradation product; a cresol degradation product; a tar-derivative product; a tar-derivative degradation product; and a liquid portion comprising lignin; lignin depolymerization products; creosote degradation products; cresol degradation products.

[0020] According to a preferred embodiment of the present invention, said method further comprises the steps of: removing said liquid portion; washing the contaminated cellulose portion with an organic solvent; separating a washed cellulose from said organic solvent; recovering said washed cellulose portion; optionally, washing said washed cellulose portion with water and neutralizing it to a pH ranging from 5 to 9, thereby obtaining a neutralized cellulose portion; exposing said neutralized cellulose portion to an enzyme blend to produce a hydrolysate comprising sugars obtained from the hydrolysis of cellulose and hemicellulose; and optionally, fermenting said hydrolysate with a fermenting organism to produce value-added products.

[0021] According to a preferred embodiment of the present invention, said value-added product is selected from the group comprising of: organic acids (i.e., formic acid, acetic acid), alcohols (i.e., ethanol, isopropanol, isobutanol, n-butanol, propanol), ketones (i.e., acetone), gases (i.e., methane, carbon dioxide, hydrogen sulfide) and combinations thereof. In a preferred embodiment of the present invention, the value- added product is ethanol. In another preferred embodiment of the present invention, the value-added product is methane.

[0022] Preferably, said method further comprises a step of pre-extraction by exposing said processed particles to a solvent capable of dissolving creosote. According to a preferred embodiment of the present invention, said reactive phase and the holding phase are present in a weight ratio ranging from 2: 1 to 1:2. Preferably, the reactive phase and the holding phase are pre sent in a weight ratio ranging from 1.5: I to 1: 1.5.

[0023] According to a preferred embodiment of the present invention, said holding phase comprises a solvent selected from the group consisting of: Ci-Ce linear alcohol; C’s-C,, branched alcohol and mixtures thereof. Prefemably, the holding phase comprises a solvent selected from the group consisting of: ethyl acetate; propyl acetate; butyl acetate; and combinations thereof.

[0024] According to a preferred embodiment of the present invention, the sulfuric acid and the source of peroxide are pre sent in a molar ratio ranging from 3 : 1 to 1 : 3. Preferably , the sulfuric acid and the modifying agent are present in a molar ratio ranging from 10: 1 to 1: 10. More preferably the sulfuric acid and the modifying agent are present in a molar ratio ranging from 3: 1 to 1:3. Even more preferably, the sulfuric acid and the modifying agent are present in a molar ratio ranging from 3 : 1 to 1: 1.

[0025] According to a preferred embodiment of the present invention, said alcohol is selected from the group consisting of: methanol; ethanol; n-propanol; isopropanol; n-butanol; and isobutanol. Preferably, the alcohol and the sulfuric acid are present in a molar ratio ranging from 1 : 1 (alcohol : sulfuric acid) to 10: 1 (alcohol : sulfuric acid). More preferably, the alcohol and the sulfuric acid are present in a molar ratio ranging from 3: 1 (alcohol : sulfuric acid) to 5: 1 (alcohol : sulfuric acid).

[0026] According to a preferred embodiment of the present invention, the peroxide and the sulfuric acid are present in a molar ratio ranging from 1.5: 1 (peroxide: sulfuric acid) to 1: 10 (peroxide: sulfuric acid). Preferably, peroxide and the sulfuric acid are present in a molar ratio ranging from 1:3 (peroxide: sulfuric acid) to 1:7 (peroxide: sulfuric acid). More preferably, the peroxide and the sulfuric acid are present in a molar ratio of approximately 1:5 (peroxide: sulfuric acid).

[0027] According to a preferred embodiment of the present invention, said peroxide and the alcohol are present in a molar ratio ranging from 1: 1 (peroxide: alcohol) to 1:20 (peroxide: alcohol). Preferably, the peroxide and the alcohol are present in a molar ratio ranging from 1:5 (peroxide: alcohol) to 1: 15 (peroxide: alcohol). More preferably the peroxide and the alcohol are present in a molar ratio ranging from 1:7 (peroxide: alcohol) to 1: 10 (peroxide: alcohol). According to a preferred embodiment of the present invention, the alcohol is selected from the group consisting of: methanol; ethanol; n-propanol; isopropanol; n-butanol; isobutanol and mixtures thereof.

[0028] According to a preferred embodiment of the present invention, the alcohol and the sulfuric acid are present in a molar ratio ranging from 1:2 (alcohol : sulfuric acid) to 10: 1 (alcohol : sulfuric acid). Preferably, the alcohol and the sulfuric acid are present in a molar ratio ranging from 1 : 1 (alcohol : sulfuric acid) to 2: 1 (alcohol : sulfuric acid).

[0029] According to a preferred embodiment of the present invention, the peroxide and the sulfuric acid are present in a molar ratio ranging from 1.5: 1 (peroxide: sulfuric acid) to 1: 10 (peroxide: sulfuric acid). Preferably, the peroxide and the sulfuric acid are present in a molar ratio ranging from 1: 1 (peroxide: sulfuric acid) to 1 :3 (peroxide: sulfuric acid). More preferably, the peroxide and the sulfuric acid are present in a molar ratio of approximately 1: 1 (peroxide: sulfuric acid).

[0030] According to a preferred embodiment of the present invention, the peroxide and the alcohol are present in a molar ratio ranging from 2: 1 (peroxide: alcohol) to 1: 10 (peroxide: alcohol). Preferably, the peroxide and the alcohol are present in a molar ratio ranging from 1 : 1 (peroxide: alcohol) to 1 :5 (peroxide: alcohol). More preferably, the peroxide and the alcohol are present in a molar ratio ranging from 1: 1 (peroxide: alcohol) to 1:2 (peroxide: alcohol).

[0031] According to another aspect of the present invention, there is provided a one-pot process to separate creosote from a lignocellulosic feedstock, said process comprising the steps of:

[0032] - providing a vessel;

[0033] - providing said creosote-containing lignocellulosic feedstock;

[0034] - providing an acidic composition having a pH of less than 1, said acidic composition comprising: o -an acid selected from the group consisting of:

[0035] ■ sulfuric acid;

[0036] ■ an alkylsulfonic acid; and

[0037] ■ an arylsulfonic acid; o a source of peroxide; o an alcohol selected from the group consisting of Ci-Cg linear alcohol and C’s-C,, branched alcohol; - exposing said lignocellulosic feedstock to said composition in said vessel for a period of time sufficient to remove at least 80% of the creosote present in said lignocellulosic feedstock; and

[0038] - optionally, separating a liquid phase comprising dissolved lignin fragments and creosote degradation products from a solid phase comprising cellulose fibres.

[0039] Preferably, the alkylsulfonic acid is selected from the group consisting of: methanesulfonic acid; ethanesulfonic acid; propane sulfonic acid and combinations thereof. Preferably, the arylsulfonic acid is selected from the group consisting of: toluenesulfonic acid; benzenesulfonic acid; and combinations thereof.

[0040] According to another preferred embodiment of the present invention, the temperature of the composition prior to the step of exposing it to the lignocellulosic feedstock is below 50 °C. Preferably, the temperature of the composition prior to the step of exposing it to the lignocellulosic feedstock is below 40 °C . More preferably, the temperature of the composition prior to the step of exposing it to the lignocellulosic feedstock is below 30 °C. Most preferably, the temperature of the composition prior to the step of exposing it to the lignocellulosic feedstock is below 25 °C.

[0041] According to a preferred embodiment of the present invention, the period of time is sufficient to remove at least 90% of the creosote present on said plant material. More preferably, the period of time is sufficient to remove at least 95% of the creosote present on said plant material.

[0042] According to a preferred embodiment of the present invention, the method is carried out at ambient temperature. According to a preferred embodiment of the present invention, the method is carried out at atmospheric pressure.

[0043] BRIEF DESCRIPTION OF THE FIGURES

[0044] The invention may be more completely understood in consideration of the following description of various embodiments of the invention in connection with the accompanying figure, in which:

[0045] Figure 1 is a gas chromatography mass spectrometry (GCMS) chromatogram of an isopropyl alcohol extract of creosote wood before treatment

[0046] Figure 2 is a gas chromatography mass spectrometry (GCMS) chromatogram of Figure 1, zoomed in to show specific compound peaks

[0047] Figure 3 is a gas chromatography mass spectrometry (GCMS) chromatogram of Figure 1, zoomed in to show specific compound peaks Figure 4 is a gas chromatography mass spectrometry (GCMS) chromatogram of the products isolated from the aqueous delignification treatment of standard (non-extracted) creosote wood

[0048] Figure 5 is a gas chromatography mass spectrometry (GCMS) chromatogram of the products isolated from the aqueous delignification treatment of the isopropanol pre -treated creosote wood

[0049] Figure 6 is a gas chromatography mass spectrometry (GCMS) chromatogram of the products isolated from the organosolv delignification treatment on creosote wood

[0050] Figure 7 is a gas chromatography mass spectrometry (GCMS) chromatogram of Figure 5, zoomed in to show specific compound peaks

[0051] Figure 8 is a gas chromatography mass spectrometry (GCMS) chromatogram of Figure 5, zoomed in to show specific compound peaks

[0052] Figure 9 is a gas chromatography mass spectrometry (GCMS) chromatogram of Figure 5, zoomed in to show specific compound peaks

[0053] Figure 10 is a gas chromatography mass spectrometry (GCMS) chromatogram of the untreated cresol mixed isomers (85% purity), also showing contaminants

[0054] Figure 11 is a gas chromatography mass spectrometry (GCMS) chromatogram of Figure 10, zoomed in to show specific compound peaks

[0055] Figure 12 is a gas chromatography mass spectrometry (GCMS) chromatogram of Figure 10, zoomed in to show specific compound peaks

[0056] Figure 13 is a gas chromatography mass spectrometry (GCMS) chromatogram of the products isolated from the aqueous delignification treatment of the cresol isomers reference standard

[0057] Figure 14 is a gas chromatography mass spectrometry (GCMS) chromatogram of the products isolated from the organosolv delignification treatment of cresol isomers after a 3 -hour reaction

[0058] Figure 15 is a gas chromatography mass spectrometry (GCMS) chromatogram of the mixture of compounds resulting from the delignification of cresols in an 18 hour Organosolv reaction according to a preferred embodiment of the present invention;

[0059] Figure 16 is a graph comparing the ethanol conversion yields of a railroad tie cellulose washed 6 times vs railroad tie cellulose washed once (Experiment #11);

[0060] Figure 17 is a graph showing the percent cellulose to ethanol conversion of railroad tie cellulose, railroad tie biomass and hardwood biomass from Experiment #11; and

[0061] Figure 18 is a graph depicting the biochemical methane potential (in mb of CH4 / g volatile solids) of the railroad tie cellulose compared to a hardwood cellulose delignified using the same procedure as well as a railroad tie biomass wherein no delignification has occurred according to Experiment #14.

[0062] DESCRIPTION OF THE INVENTION Preferably, the railroad ties comprises lignin, hemicellulose and cellulose fibers and are delignified by exposure to a modified Caro’s acid composition selected from the group consisting of: composition A; composition B and Composition C; wherein said composition A comprises:

[0063] - sulfuric acid in an amount ranging from 20 to 70 wt % of the total weight of the composition;

[0064] - a modifier compound comprising an amine moiety and a sulfonic acid moiety selected from the group consisting of: taurine; taurine derivatives; and taurine- related compounds; and

[0065] - a peroxide; wherein said composition B comprises:

[0066] - an alkylsulfonic acid; and

[0067] - a peroxide; wherein the acid is present in an amount ranging from 40 to 80 wt % of the total weight of the composition and where the peroxide is present in an amount ranging from 10 to 40 wt % of the total weight of the composition; wherein said composition C comprises:

[0068] - sulfuric acid;

[0069] -a two-part modifier comprising:

[0070] - a compound comprising an amine moiety; and

[0071] - a compound comprising a sulfonic acid moiety; and

[0072] - a peroxide.

[0073] According to a preferred embodiment of the present invention, exposing said biomass to said modified Caro’s acid composition will allow the delignification reaction to occur and remove over 90 wt % of said lignin and hemicellulose from said biomass.

[0074] Preferably, the delignification reaction is carried out at a temperature below 55 °C by a method selected from the group consisting of:

[0075] - adding water into said vessel;

[0076] - adding biomass into said vessel; and

[0077] - using a heat exchanger.

[0078] Preferably, said sulfuric acid, said compound comprising an amine moiety and a sulfonic acid moiety and said peroxide are present in a molar ratio of no less than 1:1: 1. Also preferably, said sulfuric acid, said compound comprising an amine moiety and a sulfonic acid moiety and said peroxide are present in a molar ratio of no more than 15: 1: 1. Preferably, said sulfuric acid and said compound comprising an amine moiety and a sulfonic acid moiety are present in a molar ratio of no less than 3: 1.

[0079] According to a preferred embodiment of the method to delignify biomass as set out herein, said modifier compound comprises an amine moiety and a sulfonic acid moiety is selected from the group consisting of: taurine; taurine derivatives; and taurine -related compounds.

[0080] According to a preferred embodiment of the method to delignify biomass as set out herein, said taurine derivative or taurine -related compound is selected from the group consisting of: taurolidine; taurocholic acid; tauroselcholic acid; tauromustine; 5-taurinomethyluridine and 5-taurinomethyl-2- thiouridine; homotaurine (tramiprosate); acamprosate; and taurates; as well as aminoalkylsulfonic acids where the alkyl is selected from the group consisting of C1-C5 linear alkyl and C1-C5 branched alkyl. Preferably, said linear alkylaminosulfonic acid is selected form the group consisting of: methyl; ethyl (taurine); propyl; and butyl. Preferably, said branched aminoalkylsulfonic acid is selected from the group consisting of: isopropyl; isobutyl; and isopentyl.

[0081] According to a preferred embodiment of the present invention, said modifier compound comprising an amine moiety and a sulfonic acid moiety is taurine.

[0082] According to a preferred embodiment of the present invention, said sulfuric acid and compound comprising an amine moiety and a sulfonic acid moiety are present in a molar ratio of no less than 3: 1.

[0083] According to a preferred embodiment of the present invention, said compound comprising an amine moiety is an alkanolamine is selected from the group consisting of: monoethanolamine; diethanolamine; triethanolamine; and combinations thereof.

[0084] According to a preferred embodiment of the present invention, said compound comprising a sulfonic acid moiety is selected from the group consisting of: alkylsulfonic acids and combinations thereof.

[0085] According to a preferred embodiment of the present invention, said alkylsulfonic acid is selected from the group consisting of: alkylsulfonic acids where the alkyl groups range from Ci-Ce and are linear or branched; and combinations thereof. According to a preferred embodiment of the present invention, said alkylsulfonic acid is selected from the group consisting of: methanesulfonic acid; ethanesulfonic acid; propanesulfonic acid; 2- propane sulfonic acid; isobutylsulfonic acid; t-butylsulfonic acid; butanesulfonic acid; iso- pentylsulfonic acid; t-pentylsulfonic acid; pentanesulfonic acid; t-butylhexanesulfonic acid; and combinations thereof.

[0086] According to a preferred embodiment of the present invention, said alkylsulfonic acid; and said peroxide are present in a molar ratio of no less than 1: 1.

[0087] According to a preferred embodiment of the present invention, said compound comprising a sulfonic acid moiety is methane sulfonic acid.

[0088] According to a preferred embodiment of the present invention, in Composition C, said sulfuric acid and said a compound comprising an amine moiety and said compound comprising a sulfonic acid moiety are present in a molar ratio of no less than 1: 1: 1.

[0089] According to a preferred embodiment of the present invention, in Composition C, said sulfuric acid, said compound comprising an amine moiety and said compound comprising a sulfonic acid moiety are present in a molar ratio ranging from 28: 1: 1 to 2: 1: 1.

[0090] According to preferred embodiment of the present invention, the modified Caro’s acid (as disclosed in Canadian patent application 3,128,678) comprises: sulfuric acid; a heterocyclic compound and a peroxide; and wherein sulfuric acid and said a heterocyclic compound; are present in a molar ratio of no less than 1: 1. Preferably, the sulfuric acid and said heterocyclic compound are present in a molar ratio ranging from 28: 1 to 2: 1 More preferably, the sulfuric acid and heterocyclic compound are present in a molar ratio ranging from 24: 1 to 3: 1. Preferably, the sulfuric acid and heterocyclic compound are present in a molar ratio ranging from 20: 1 to 4: 1. More preferably, the sulfuric acid and heterocyclic compound are present in a molar ratio ranging from 16: 1 to 5: 1. Preferably, the sulfuric acid and heterocyclic compound are present in a molar ratio ranging from 12: 1 to 6: 1. Also preferably, said heterocyclic compound has a molecular weight below 300 g / mol. Also preferably, said heterocyclic compound has a molecular weight below 150 g / mol. More preferably, said heterocyclic compound is a secondary amine. According to a preferred embodiment of the present invention, said heterocyclic compound is selected from the group consisting of: imidazole; triazole; and N-methylimidazole. According to preferred embodiment of the present invention, the modified Caro’s acid (as disclosed in Canadian patent application 3,128,677) comprises: sulfuric acid; a modifying agent comprising a compound containing an amine group and a peroxide; and wherein sulfuric acid and said compound containing an amine group; are present in a molar ratio of no less than 1: 1. Preferably, the sulfuric acid and said compound containing an amine group are present in a molar ratio ranging from 28: 1 to 2: 1. More preferably, the sulfuric acid and compound containing an amine group are present in a molar ratio ranging from 24: 1 to 3: 1. Preferably, the sulfuric acid and compound containing an amine group are present in a molar ratio ranging from 20: 1 to 4: 1. More preferably, the sulfuric acid and compound containing an amine group are present in a molar ratio ranging from 16: 1 to 5: 1. Preferably, the sulfuric acid and compound containing an amine group are present in a molar ratio ranging from 12: 1 to 6: 1. According to a preferred embodiment of the present invention, the modifying agent is selected in the group consisting of: TEOA; MEOA; pyrrolidine; DEOA; ethylenediamine; diethylamine; triethylamine; morpholine; MEA-triazine; and combinations thereof. According to a more preferred embodiment of the present invention, the modifying agent is TEOA; MEOA; pyrrolidine; DEOA; ethylenediamine; triethylamine.

[0091] According to preferred embodiment of the present invention, the modified Caro’s acid (as disclosed in Canadian patent application 3,128,676) comprises: sulfuric acid; a modifying agent comprising an alkanesulfonic acid and a peroxide; and wherein sulfuric acid and said alkanesulfonic acid are present in a molar ratio of no less than 1: 1. Preferably, said alkanesulfonic acid is selected from the group consisting of: alkanesulfonic acids where the alkyl groups range from CI-C6 and are linear or branched; and combinations thereof. Preferably, said alkanesulfonic acid is selected from the group consisting of: methanesulfonic acid; ethane sulfonic acid; propane sulfonic acid; 2-propanesulfonic acid; isobutylsulfonic acid; t-butylsulfonic acid; butanesulfonic acid; iso-pentylsulfonic acid; t-pentylsulfonic acid; pentanesulfonic acid; t-butylhexanesulfonic acid; and combinations thereof. More preferably, said alkanesulfonic acid is methanesulfonic acid. Also preferably, said alkanesulfonic acid has a molecular weight below 300 g / mol. Also preferably, said alkanesulfonic acid has a molecular weight below 150 g / mol. Preferably, the sulfuric acid and said alkanesulfonic acid and are present in a molar ratio ranging from 28: 1 to 2: 1. More preferably, the sulfuric acid and alkanesulfonic acid are present in a molar ratio ranging from 24: 1 to 3 : 1. Preferably, the sulfuric acid and alkanesulfonic acid are present in a molar ratio ranging from 20: 1 to 4: 1. More preferably, the sulfuric acid and alkanesulfonic acid are present in a molar ratio ranging from 16: 1 to 5: 1. According to a preferred embodiment of the present invention, the sulfuric acid and alkanesulfonic acid are present in a molar ratio ranging from 12: 1 to 6: 1. According to preferred embodiment of the present invention, the modified Caro’s acid (as disclosed in Canadian patent application 3,128,675) comprises: sulfuric acid; a substituted aromatic compound and a peroxide; and wherein sulfuric acid and said substituted aromatic compound; are present in a molar ratio of no less than 1: 1. Preferably, the substituted aromatic compound comprises at least two substituents. More preferably, at least one substituent is an amine group and at least one of the other substituent is a sulfonic acid moiety. According to a preferred embodiment, the substituted aromatic compound comprises three or more substituent. According to a preferred embodiment of the present invention, the substituted aromatic compound comprises at least a sulfonic acid moiety. According to another preferred embodiment of the present invention, the substituted aromatic compound comprises an aromatic compound having a sulfonamide substituent, where the compound can be selected from the group consisting of: benzenesulfonamides; toluenesulfonamides; substituted benzenesulfonamides; and substituted toluenesulfonamides. Preferably, the sulfuric acid and said substituted aromatic compound and are present in a molar ratio ranging from 28: 1 to 2: 1. More preferably, the sulfuric acid and substituted aromatic compound are present in a molar ratio ranging from 24: 1 to 3 : 1. Preferably, the sulfuric acid and substituted aromatic compound are present in a molar ratio ranging from 20: 1 to 4: 1. More preferably, the sulfuric acid and substituted aromatic compound are present in a molar ratio ranging from 16: 1 to 5: 1. Preferably, the sulfuric acid and substituted aromatic compound are present in a molar ratio ranging from 12: 1 to 6: 1.

[0092] According to preferred embodiment of the present invention, the modified Caro’s acid (as disclosed in Canadian patent application 3,128,674) comprises: sulfuric acid; a modifying agent comprising an arylsulfonic acid; a peroxide; and optionally, a compound containing an amine group; wherein sulfuric acid and said a arylsulfonic acid; are present in a molar ratio of no less than 1: 1. Preferably, the compound containing an amine group is selected from the group consisting of: imidazole; N-methylimidazole; triazole; monoethanolamine (MEO A); diethanolamine (DEO A); triethanolamine (TEO A); pyrrolidine and combinations thereof. According to a preferred embodiment of the present invention, sulfuric acid and the peroxide are present in a molar ratio of approximately 1: 1. Preferably, the sulfuric acid and said arylsulfonic acid and are present in a molar ratio ranging from 28: 1 to 2: 1. More preferably, the sulfuric acid and arylsulfonic acid are present in a molar ratio ranging from 24: 1 to 3: 1. Preferably, the sulfuric acid and arylsulfonic acid are present in a molar ratio ranging from 20: 1 to 4: 1. More preferably, the sulfuric acid and arylsulfonic acid are present in a molar ratio ranging from 16: 1 to 5: 1. According to a preferred embodiment of the present invention, the sulfuric acid and arylsulfonic acid are present in a molar ratio ranging from 12: 1 to 6: 1. Also preferably, said arylsulfonic acid has a molecular weight below 300 g / mol. Also preferably, said arylsulfonic acid has a molecular weight below 150 g / mol. Even more preferably, said arylsulfonic acid is selected from the group consisting of: orthanilic acid; metanilic acid; sulfanilic acid; toluenesulfonic acid; benzenesulfonic acid; and combinations thereof.

[0093] According to preferred embodiment of the present invention, the modified Caro’s acid (as disclosed in Canadian patent application 3,128,673) comprises: sulfuric acid; a heterocyclic compound; an alkanesulfonic acid and a peroxide; and wherein sulfuric acid and said a heterocyclic compound; are present in a molar ratio of no less than 1: 1. Preferably, said aqueous acidic composition comprising: sulfuric acid; a heterocyclic compound; an arylsulfonic acid; and wherein sulfuric acid and said a heterocyclic compound; are present in a molar ratio of no less than 1: 1. Preferably, the arylsulfonic acid is toluenesulfonic acid. Preferably, the sulfuric acid, the heterocyclic compound and the alkane sulfonic acid are present in a molar ratio ranging from 28: 1: 1 to 2: 1: 1. More preferably, the sulfuric acid the heterocyclic compound and the alkanesulfonic acid are present in a molar ratio ranging from 24: 1 : 1 to 3 : 1 : 1. Preferably, the sulfuric acid, the heterocyclic compound and the alkanesulfonic acid are present in a molar ratio ranging from 20: 1 : 1 to 4: 1: 1. More preferably, the sulfuric acid, the heterocyclic compound and the alkanesulfonic acid are present in a molar ratio ranging from 16: 1: 1 to 5: 1: 1. According to a preferred embodiment of the present invention, the sulfuric acid and heterocyclic compound are present in a molar ratio ranging from 12: 1: 1 to 6: 1: 1. Also preferably, said heterocyclic compound has a molecular weight below 300 g / mol. Also preferably, said heterocyclic compound has a molecular weight below 150 g / mol. Even more preferably, said heterocyclic compound is selected from the group consisting of: imidazole; triazole; n-methylimidazole; and combinations thereof. Preferably, the alkanesulfonic acid is selected from the group consisting of: alkylsulfonic acids where the alkyl groups range from C1-C6 and are linear or branched; and combinations thereof. Preferably, said alkylsulfonic acid is selected from the group consisting of: methanesulfonic acid; ethane sulfonic acid; propanesulfonic acid; 2-propanesulfonic acid; isobutylsulfonic acid; t-butylsulfonic acid; butanesulfonic acid; iso-pentylsulfonic acid; t-pentylsulfonic acid; pentanesulfonic acid; t-butylhexanesulfonic acid; and combinations thereof. More preferably, said alkylsulfonic acid is methane sulfonic acid.

[0094] According to preferred embodiment of the present invention, the modified Caro’s acid (as disclosed in Canadian patent application 3,128,672) comprises: sulfuric acid; a carbonyl-containing nitrogenous base compound and a peroxide; and wherein sulfuric acid and said a carbonyl-containing nitrogenous base compound; are present in a molar ratio of no less than 1: 1. According to a preferred embodiment of the present invention, the carbonyl -containing nitrogenous base compound is selected from the group consisting of: caffeine; lysine; creatine; glutamine; creatinine; 4-aminobenzoic acid; glycine; NMP (N- methyl-2-pyrrolidinone); histidine; DMA (N,N-dimethylacetamide); arginine; 2,3-pyridinedicarboxylic acid; hydantoin; and combinations thereof. Preferably, the sulfuric acid and said carbonyl-containing nitrogenous base compound and are present in a molar ratio ranging from 28: 1 to 2: 1. More preferably, the sulfuric acid and carbonyl -containing nitrogenous base compound are present in a molar ratio ranging from 24: 1 to 3: 1. Preferably, the sulfuric acid and carbonyl -containing nitrogenous base compound are present in a molar ratio ranging from 20: 1 to 4: 1. More preferably, the sulfuric acid and carbonyl -containing nitrogenous base compound are present in a molar ratio ranging from 16: 1 to 5: 1. According to a preferred embodiment of the present invention, the sulfuric acid and carbonyl -containing nitrogenous base compound are present in a molar ratio ranging from 12: 1 to 6: 1.

[0095] Examples

[0096] Carrying out delignification of lignocellulosic biomass using a method according to a preferred embodiment of the present invention provides for several advantages, including but not limited to: increase in the rates of reaction by shifting the equilibrium chemical reaction towards the product side; reducing the overall process time; and allow more facile separation of potential products which are not water-soluble but which are soluble in an organic solvent. Additional advantages of the present invention will be set forth in part in the description that follows, and in part will be obvious from the description, or can be learned by practice of the aspects described below. The advantages described below will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive.

[0097] The modified acid compositions were clear with densities ranging between 0.9 and 1.8 g / cm3.

[0098] When performing delignification of railroad ties using a composition using a modified Caro’s acid according to a preferred embodiment of the present invention, the process can be carried out at substantially lower temperatures than temperatures used in the conventional kraft pulping process.

[0099] The advantages are substantial, here are a few: the kraft pulping process requires temperatures in the vicinity of 176 - 180 °C in order to perform the delignification process, a preferred embodiment of the process according to the present invention can delignify railroad ties at far lower temperatures, even as low as 20 °C. According to a preferred embodiment of the present invention, the delignification can be performed at temperatures as low as 30 °C. According to another preferred embodiment of the present invention, the delignification of wood can be performed at temperatures as low as 40 °C. According to yet another preferred embodiment of the present invention, the delignification can be performed at temperatures as low as 50 °C. According to yet another preferred embodiment of the present invention, the delignification can be performed at temperatures as low as 60 °C. Other advantages include: a lower input of energy; reduction of emissions and reduced capital expenditures; reduced maintenance; lower shut down / turn around costs; also, there are HSE advantages compared to conventional kraft pulping compositions.

[0100] In each one of preferred embodiments disclosed herein, the temperature at which the processes are carried out are substantially lower than the current energy-intensive kraft process.

[0101] According to a preferred embodiment of the present invention, the acidic composition is selected from the group consisting of:

[0102] - sulfuric acid in an amount ranging from 20 to 70 wt% of the total weight of the composition and a peroxide; and

[0103] - an alkylsulfonic acid; and a peroxide; wherein the acid is present in an amount ranging from 30 to 80 wt% of the total weight of the composition and where the peroxide is present in an amount ranging from 1 to 40 wt % of the total weight of the composition.

[0104] According to a preferred embodiment of the present invention, the use of an acidic composition on lignocellulosic feedstock achieves two goals: it delignifies the feedstock yielding solid cellulose fibers separated from dissolved lignin breakdown products and it allows for easier separation of contaminants found in the liquid phase prior to treatment for biofuel production. Preferably, the reaction of lignocellulosic feedstock with an acidic composition according to a preferred embodiment of the present invention allows for the conversion of several lignin breakdown products into valuable ester or diester compounds such as, but not limited to, diethyl malonate; diethyl maleate; diethyl succinate; and diethyl oxalate.

[0105] Procedure for modified organosolv treatment of biomass according to a preferred embodiment

[0106] The purpose of this set of experiments is to determine whether delignification with a modified Caro’s acid or organosolv-type delignification blend can extract or degrade coal tar contained in railroad ties and separate it from the cellulose fibre which is typically obtained by a delignification process using a modified Caro’s acid.

[0107] Because the creosote is composed primarily of aromatics there is good reason to hypothesize that our delignification process will degrade these compounds similarly to the lignin in wood. Based on the research provided below it is likely that the railroad tie wood provided is of the coal-tar variety due to the null detection of cresols and the high amount of PAH’s.

[0108] The typical delignification blend does not provide a good solvent for the solubilizing the hydrophobic constituents of the coal tar, though does appear to continue to break down the wood fibres and separate out delignified cellulose (though with high amounts of tar still present in the fibres).

[0109] The leftover creosote contamination is the reason an organosolv-type process was employed, to both extract the hydrophobic compounds from the cellulose as well as provide a medium for greater reactivity of the creosote when solubilized. Organic solvents may also be used to pre-extract the creosote material, as well as wash this material out of the delignified cellulose.

[0110] Experiment #1: Semi-Large-Scale Reactions

[0111] Procedure

[0112] Delignification reactions were executed in a mix between 500 mL beakers and a 10 L Buchi glass reactor. The reaction temperature was controlled by silicon oil baths or the reactor’s jacket and a chiller respectively. The reaction temperature was set to 35°C, operating on a 6 Kg blend with a mixing rate of 150 RPM. Reactions were run for 3 or 18-hr, with Buchi reactions being all 18-hr.

[0113] The reactions were performed with 3% feedstock loading. The moisture content of the feedstock was measured via loss on drying, but the biomass was fed into the reaction on an unmodified and undried basis.

[0114] Acid and hydrogen peroxide titrations were performed before and after the reactions, though cresol and organosolv reactions had unmeasurable peroxide concentrations. At the end of the reaction, the product slurry was filtered to separate the solid cellulose from the blend. The filtered cellulose was washed and photographed before storing for testing future ethanol production efficiency. A sample of the cellulose batch was dried in the oven for water content to be used for cellulose yield calculations.

[0115] For pre -extraction experiments 300 mL of isopropanol was used to extract 9.0 g of creosote treated wood in a 500 mL beaker for 24 hr. The mass was reduced from the 9.0 g of initial creosote treated wood to 8.62 g and the remaining solvent was reduced and extracted for NMR and GCMS analysis. For all reactions, the final cellulose product still contained significant amounts of creosote, so isopropanol washes were employed to separate the final creosote product from the cellulose fibres. Three washes of isopropanol were used for all reactions with 200 mL per wash on the 300g scale and about 1 L for the 3000 g scale. This results in a large amount of extract but does not fully remove the creosote from the fibres resulting in a black coloured product. Dichloromethane, acetone, and ethyl acetate rinses were also performed but resulted in no difference of the final cellulose, although acetone can solubilize the sludge side product that results from the reaction.

[0116] The hydrophobic nature of the creosote product is also the reason organic solvent (organosolv) - type reactions were used to separate the creosote from the cellulose over the course of the reaction. For this reason, 25% wt. of isopropanol was used as sufficient to separate the creosote and dissolve it in the delignification medium.

[0117] The standard delignification reaction proceeded as expected and reacted in a very similar matter to the reaction when a hardwood control is used, although it did consume slightly higher levels of peroxide. This is likely because the creosote is reacting in a similar way to lignin and therefore has slightly more oxidizable material in the biomass to react with. The results of the various experiment are reported in Table 1 below.

[0118] Table 1: Creosote Wood Experiments at 35 °C

[0119] Extending reaction times shows the same trend as standard hardwood by decreasing the yield of cellulose while increasing the amount of peroxide consumed over the course of the reaction. The increased reaction times do come with the benefit of having a higher degree of delignification of the biomass and may be seen by lighter coloured chips.

[0120] To increase the efficiency of the reaction and decrease the remaining contaminating creosote, isopropanol alcohol was used both as a reaction medium, a pre -extraction method, and a washing agent. This is because the hydrophobic nature of the creosote makes its removal difficult in the aqueous environment of a modified Caro’s acid composition used for delignification. All three of these techniques resulted in less-contaminated cellulose product, though pre-extraction and organosolv reaction also showed reduced peroxide consumption compared to the standard delignification blend in amounts of 20% and 65% less respectively.

[0121] Organic extracts of the delignification blend after the reaction indicate a that the creosote product treating the wood is of the coal tar variety. This is because a high percentage of the compounds extracted with ethyl acetate is a variety of polycyclic aromatic hydrocarbons (PAH), as well as diethyl malonate which is commonly extracted from untreated hardwood after delignification. These PAH’s are mostly of the condensed aromatic structure, although some do show varying degrees of oxidation with hydroxyl and ketone groups being present.

[0122] Experiment #2: Quantification of Creosote in Railroad Ties

[0123] To quantify the amount of creosote in the railroad ties a series of extractions were performed with different organic solvents. In each case, 10 g of creosote-containing wood chips were added to a flask containing 100 mb of a solvent and the mixture was heated to reflux and stirred for 18 hours. The mixture was then cooled, and the wood chips were collected by filtration. The wood was then rinsed several times with additional solvent, collected, dried overnight in a 50 C oven and then reweighed. The percent mass loss was then calculated. Results are shown in Table 2.

[0124] Table 2: % Mass Loss in Creosote Wood after Solvent Extraction

[0125] GCMS Compound Identification

[0126] Experiment #3: Creosote Wood Starting Material Main Components (IPA extract).

[0127] When looking at the traces of IPA extract from creosote wood it can be determined that there is a high percentage of polycyclic aromatic hydrocarbons present. This is an indication that the composition of the creosote is of the coal tar variety as opposed to the wood tar type, as cresol is not seen in the extract. When looking at the effects of the standard delignification treatment it can be observed that not many of the compounds changed, and extraction efficiency was quite low. The effect of the molecules show a much higher ratio of malonate esters, along with a couple oxidized forms of the PAH’s identified in the original creosote itself.

[0128] Pre-treatment of the creosote wood before delignification showed a distinct lack of organic molecules, most likely due to the solubility issue of these hydrophobic PAH’s in the delignification blend. This effect may be coupled with the fact that many of the extract molecules may have already been removed with the pre-treatment extraction with isopropanol.

[0129] When the isopropanol (organosolv) delignification reactions are applied to the creosote wood it can be identified that a much greater variety of compounds could be extracted from the wood. Along with the oxidized PAH’s, a large number of diacids were also extracted indicating that the delignification reaction proceeded more readily and degraded the lignin and creosote to a much greater extent.

[0130] Figures 1, 2, and 3 are GCMS chromatograms collected to study the various chemical compounds extracted upon delignification. Table 1 provides the list of compounds having main peaks with their respective retention times. It was noted that peak at RT 12.8-13.9 min is diisopropyl Malonate and is present in all traces.

[0131] Table 3: List of compounds with major peaks from GCMS analysis of creosote wood

[0132] Experiment #4: Standard Creosote Delignification.

[0133] Figure 4 is a GCMS chromatogram collected to study the various chemical compounds extracted upon delignification. Note that chromatogram shows compounds similar to standard extract above, but with higher ratio of malonic acid. Table 4 provides the list of compounds having main peaks with their respective retention times. Table 4: List of compounds with major peaks from GCMS analysis of Standard Creosote

[0134] Delignification

[0135] Experiment #5: Isopropanol Pre-Extracted Delignification Reaction

[0136] Figure 5 is a GCMS chromatogram collected to study the various chemical compounds extracted upon delignification.

[0137] Table 5 provides the list of compounds having main peaks with their respective retention times. Shows only two extractable compounds due to solubility issues in aqueous delignification blend. The compounds found are similar to those previously seen above albeit in a more oxidized form.

[0138] Table 5: List of compounds with major peaks from GCMS analysis of Isopropanol Pre-

[0139] Extracted Delignification Reaction.

[0140] Experiment #6: Isopropanol (Organosolv) Delignification Reaction

[0141] Figures 6, 7, 8 and 9 are GCMS chromatograms collected to study the various chemical compounds extracted upon delignification in an organosolv reaction.

[0142] Table 6 provides the list of compounds having main peaks with their respective retention times. It was observed a large variety of compounds with a greater variety of diacids detected. Table 6: List of compounds with major peaks from GCMS analysis of Isopropanol

[0143] (Organosolv) Delignification Reaction

[0144] Experiment #7: Cresols (mixed Isomers 85%)

[0145] For identifying the degradation of aromatic monomers, a mixture of cresol isomers was used. This acts as a model compound for the degradation of lignin monomers, as well as a potential creosote degradation model.

[0146] Figure 12 is a close up GCMS chromatogram of a portion of the spectra of Figure 11, with Figure 10 showing earlier retention times. Table 7 provides the list of compounds having main peaks with their respective retention times.

[0147] When looking at the effect of a delignification method using a modified Caro’s acid at conditions where the temperature is kept below 55°C during delignification and such is performed under atmospheri pressure there was a noted distinct lack of solubility, which may be the reason cresol isomers were not identified in the standard delignification extract of these cresols leading to a GCMS trace that only identifies the oxidized, and therefore more hydrophilic compounds from this reaction. The modified Caro’s acid used in the experiments consisted of sulfuric acid : hydrogen peroxide : taurine in a molar ratio of 10: 10: 1. Where an alcohol was present, the ratio was then sulfuric acid : hydrogen peroxide : taurine : alcohol in a molar ratio of 10: 10: 1 : 1. That being noted there was still a large condensation of sludge during the reaction with the extract of this sludge still showing cresols present. Therefore, this reaction was effective in breaking down the cresols and condensing them, though perhaps not to the extent as the organosolv type reactions. Table 7: List of compounds with major peaks from GCMS analysis of cresols (mixed isomers)

[0148] Experiment #8: Standard Delignification Blend On Cresols

[0149] When exposed to the organosolv blends, there was a significant change in both the solubility of the cresols over the course of the reaction, as well as a large distinction in the molecules that could be extracted after the reaction was complete.

[0150] In the 3 hour run, there are 6 prominent peaks identified: malonic acid diisopropyl ester (rt= 13.88), butenedioic acid dimethyl ester (rt=16.22), Succinic acid (rt=18.1O), P-Cresol (19.58), and an oxidized furan (5-hydroxy-2,5-dimethyldihydrofuran-2-one) (rt=23.15). This represents a large conversion of cresols to diacids that have not been identified in the standard delignification on cresols, though also contains the oxidized furan previously identified in the non-organosolv blend.

[0151] When observing the reaction products from the 18 -hour organosolv reaction, many of the same diacids were present in the organic extract (malonic, butenedioic, succinic) as well as the oxidized furanone, though the biggest difference identified in the 18-hr reaction is the distinct lack of P-Cresol, indicating that this time difference was enough to degrade the remaining cresol into the remaining diacids. This can also be noted by the increased ratio of diacids to furanone, though the ratios of diacids to each other appear to remain constant.

[0152] Figure 13 is a GCMS chromatogram collected to study the various chemical compounds extracted upon delignification on cresols. Note the loss of large cresol peaks RT=16-20 min. Table 6 provides the list of compounds having main peaks along with their respective retention times. Table 6: List of compounds with major peaks from GCMS analysis of compounds recovered in experiment #6

[0153] Experiment #9: Cresol reaction in a 3-hour Organosolv reaction

[0154] Figure 14 is a GCMS chromatogram collected to study the various chemical compounds extracted upon delignification on cresols during a 3-hour reaction. Note the presence of large cresol peaks RT=16- 20 min.

[0155] Experiment #10: Cresol reaction in an 18-hour Organosolv reaction

[0156] Figure 15 is a GCMS chromatogram collected to study the various chemical compounds extracted upon delignification on cresols during a 18 hour reaction. Note the absence of large cresol peaks RT=16- 20 min.

[0157] Experiment #11: Comparison of Organosolv Cresol Runs

[0158] Figures 14 and 15 are GCMS chromatograms collected to study the various chemical compounds extracted upon delignification on cresols during a 18-hour reaction (Figure 15) and a 3-hour reaction (Figure 14). Note loss of cresol on GCMS trace between 18-hr and 3-hr runs at (RT=19.59)

[0159] Observations:

[0160] Cresote wood provided was of the coal tar (PAH) variety instead of the wood tar (Cresols) variety, though cresol was still used as a model compound to prove degradation using a delignification process using a modified Caro’s acid.

[0161] For both creosote and cresol, organosolv reactions performed better by solubilizing the hydrophobic compound within. Peroxide consumption was reduced on creosote with both the preextraction and organosolv experiments, with the later having significant reduction in peroxide consumption.

[0162] All creosote experiments required a post-wash with IPA to remove excess organics from the cellulose, though this left the cellulose still dark and contaminated after the washes. An alkali wash after the post-reaction IPA wash has a propensity to reduce this contamination by solubilizing it in water. It can be seen from the delignification process only using a modified Caro’s acid that the blend is too aqueous to capture most of the organic molecules resulting in only two identifiable peaks in GCMS, whereas a number of compounds can be identified in the organosolv reactions when such employed a modified Caro’s acid.

[0163] Cresols did not solubilize well in delignification experiments employing a modified Caro’s acid, though did in the organosolv experiments.

[0164] The 3-hour organosolv reactions were not enough to eliminate all the cresol. The 18-hour experiments were able to eliminate all detectable cresol. Several oxidations and condensation reactions appear to have occurred in cresol due to the large number of diacids identified in the longer duration reactions. Interestingly, the cresols have degraded in a pattern similar to that of lignin, forming the same diacids as a result of the reaction.

[0165] The presence of the creosote, as well as other contaminants, are very likely toxic to the yeast present in the SSF reaction and will therefore not ferment. However, the delignification process using a modified Caro’s acid appears to have mitigated the toxic effects of the creosote and other contaminants by degrading them into small chain diacids, resulting in ethanol yields of railroad tie cellulose comparable to those of uncontaminated hardwood cellulose.

[0166] Experiment #12: Cellulosic Ethanol

[0167] Procedure

[0168] Samples of railroad ties were delignified as per the method described hereinabove. After the reaction was considered complete, the solid cellulose stream was filtered out from the liquid stream and rinsed 3 times with isopropanol in order to remove residual contaminants. The acidic slurry was resuspended in water to approximately 3-5% solids content and blended for 2 minutes. The slurry was then neutralized to achieve a pH of 7. The solids were subsequently rinsed with tap water. Two rinsing approaches were evaluated:

[0169] • Rinsing of solids with tap water using a 10: 1 ratio of water to cellulose by weight until no more ionic salts were extracted. A total of 6 rinses with tap were performed, filtrates shown in Figure 6.

[0170] • Rinsing of solids once using a 3: 1 ratio of water to cellulose by weight.

[0171] Cellulose to ethanol conversion was tested via simultaneous saccharification and fermentation (SSF). Solids samples, as well as controls with no cellulose, were placed in a vessel containing a buffer at a pH of 5.3, at a loading of 5 % w / w (oven dry) alongside a commercially available enzyme blend. It it noted that the solids are not dried post-rinsing and thus, they may contain up to 90 % water. The loading of the enzyme blend was that of 3 mg of enzyme / g of wet solids. To that, an ethanologenic organism (i.e., Saccharomyces cerevisiae) was added. The flasks were stoppered with fermentation airlocks to create an anaerobic environment to promote fermentation and incubated at 37 °C, shaking at 150 rpm. Aliquots of the samples were collected every 24 hours to monitor the production of ethanol over 4 days of incubation.

[0172] Results

[0173] It was determined that ethanol yields for cellulose obtained from delignified railroad ties for both washing approaches were comparable to one another. A maximum conversion of cellulose to ethanol of 73% was obtained on the delignified railroad tie cellulose washed 6 times, while a 79 % conversion was obtained on the delignified railroad tie cellulose washed 1 time (Figure 16). This concludes that extra washing did not really increase the ethanol yields; which lowers the operational and environmental costs associated with the extra washing steps.

[0174] Experiment #13: Cellulosic Ethanol

[0175] This experiment was conducted to compare the efficiency of the conversion of railroad ties cellulose to ethanol in comparison with a non -contaminated hardwood sample.

[0176] Procedure

[0177] Samples of railroad ties were delignified as per the method described hereinabove. After the reaction was considered complete, the solid cellulose stream was filtered out from the liquid stream and rinsed 3 times with isopropanol in order to remove residual contaminants. The acidic slurry was resuspended in water, blended for 2 minutes and washed once with tap water.

[0178] A non-contaminated hardwood sample was also delignified according to a procedure described herein using a modified Caro’s acid. After the reaction was considered complete, the solid cellulose stream was filtered out from the liquid stream, reslurried, neutralized and washed once with tap water.

[0179] Comparison was performed with samples of the raw undelignified biomass, namely railroad ties and non-contaminated hardwood that had been ground to 1mm.

[0180] Cellulose to ethanol conversion was tested via simultaneous saccharification and fermentation (SSF). All samples (biomass and cellulose) as well as controls with no substrate were placed in a vessel containing a buffer at a pH of 5.3, at a loading of 5 % w / w (oven dry) alongside a commercially available enzyme blend. The loading of the enzyme blend was that of 3 mg of enzyme / g of wet cellulose equivalent. To that, an ethanologenic organism (i.e., Saccharomyces cerevisiae) was added. The flasks were stoppered with fermentation airlocks to create an anaerobic environment to promote fermentation and incubated at 37 °C, shaking at 150 rpm. Aliquots of the samples were collected every 24 hours to monitor the production of ethanol over 4 days of incubation.

[0181] Cellulose Characterization

[0182] The railroad ties cellulose used for Experiment 12 was characterized to quantify the fermentable species in the sample and more accurately determine ethanol yields with respect to cellulose content. This includes determination of Kappa number, ash content, and a-, P-, and y-cellulose. The results of these tests are summarized in Table 9 below. Ash content is determined by combusting all organic species, quantifying the remaining inorganics. It is worthy to note that unique to this cellulose, the presence of organics that do not contribute to ethanol production, such as asphaltenes and tar, is not captured in this test. Therefore, saccharifiable and fermentable cellulose is likely overestimated, thus underestimating ethanol yields.

[0183] Table 9: Characterization of railroad tie cellulose following a 3:1 cellulose to water wash.

[0184] Results

[0185] Figure 17 shows that the hardwood biomass did yield a small amount of ethanol, while the creosote contaminated hardwood did not result in any detectable ethanol production. The percent conversion of the railroad tie cellulose to ethanol via SSF was approximately 79%, which is comparable to ethanol yields observed from uncontaminated delignified hardwood biomass where the delignification is carried out using a modified Caro’s acid (Figure 17).

[0186] The results lead to the conclusion that the delignification process described herein is able to remove contaminants in the railroad ties in a manner sufficient to provide ethanol yields comparable to noncontaminated delignified biomass. This signifies that this process allows for cellulose originating from biomass contaminated with compounds such as cresol and creosote to be used in the generation of ethanol by simultaneous saccharification and fermentation (SSF) thereby allowing the use of waste railroad ties as materials to generate second-generation ethanol. This constitutes a groundbreaking approach to re-using waste creosote-containing wood material rather than combustion.

[0187] According to a preferred embodiment of the process of the present invention, the process enables a conversion of cellulose derived from contaminated biomass to glucose, and sequentially ethanol, by overcoming the first step of removing the creosote, cresol and or tar derived contaminants from the biomass with the hereinabove described process.

[0188] Experiment #14: Anaerobic Digestion

[0189] The goal of this experiment was to determine the biochemical methane potential (BMP) of a coal tar-based rail tie biomass and compare it with the BMP of a substantially -free of lignin cellulose derived from a coal tar-based rail tie biomass after delignification and its creosote and other toxic materials have been degraded using a modified Caro’s acid as per a preferred embodiment of the process described herein. For comparison, a cellulose which is substantially-free of lignin and is derived from non-contaminated hardwood biomass whose lignin as been removed using a modified Caro’s acid as per a preferred embodiment of the process described herein was also used.

[0190] The coal tar-based rail tie biomass was milled to 1 mm in size and the cellulose which is substantially-free of lignin derived from said biomass and from the non-contaminated biomass was a ‘wet’ or ‘never-dried’ substrate. For the experiment preparation, the Total Solids (TS) and Volatile Solids (VS) were measured for all substrates as well as the inoculum (digestate). The inoculum was prepared by incubating it under anaerobic conditions for three days prior to setting up the serum bottles. Substrates were added to serum bottles containing the prepared inoculum in an inoculum-to-substrate mass ratio (ISR) of 0.25, 3, and 4 for the rail tie biomass and 2, 3, and 4 for the rail tie and hardwood cellulose. Corresponding substrate-free blank bottles were prepared by adding water in place of the substrate. Bottles were incubated at 35 °C for the duration of the experiment. Biogas and methane production of samples were measured as needed.

[0191] For analysis, the methane measurements were normalized to Standard Temperature Pressure (STP) conditions (101.35 kPa, 0 °C) and methane generated from the substrate-free blanks was subtracted from the methane generated from the experimental substrates. This was done to ensure that the results are a reflection of the amount of methane produced from the addition of the substrate alone. Finally, the ratio from each of the substrates that showed the clearest trend was selected for the final comparison. The results for this experiment are shown Figure 18 where the biochemical methane potential of the coal tar-based rail tie biomass is compared to its delignified equivalent as well as a cellulose obtained from delignifying virgin hardwood biomass. Figure 18 shows the biochemical methane potential of all three substrates as cumulative methane produced in mL of methane per gram of volatile solids (mL CFL / g VS) over time for rail tie biomass, rail tie-derived cellulose and hardwood derived cellulose.

[0192] As observed from Figure 18, the biochemical methane potential from the coal tar-based railroad tie biomass is zero or in some instances, negative. This highlights the toxic impact from the creosote materials present in coal tar-based railroad tie biomass on the anaerobic digester microbial community. This toxic effect leads to no cumulative methane produced over the range studied. In opposition to this, when delignifying and detoxifying said coal tar-based biomass, the toxic materials present are degraded or neutralized, and the cellulose thus obtained possesses a biochemical methane potential similar to that of a “clean” hardwood biomass where no toxic materials were present to begin with. This is a clear indication that the delignification using a modified Caro’s acid described herein has the ability to convert biomass containing highly toxic compounds into a very bioavailable cellulose product that is able to be utilized in anaerobic digestion to generate as much methane as a non -creosote contaminated equivalent cellulose.

[0193] It will be known by those skilled in the art that the process described herein provides significant benefits in comparison with existing state-of-the-art biomass delignification processes as it requires less energy due to the ambient conditions employed. The decontamination of the previously unusable biomass for generation of glucose and sequentially cellulose is enabled by this unique delignification process. In addition, the high delignification yields render the subsequent cellulose hydrolysis and fermentation highly efficient as the presence of lignin is known to be detrimental in currently existing processes due to residues in equipment and enzyme adsorption and deactivation. As a consequence to the lack of lignin, the resulting solids mostly comprising cellulose have a significantly higher surface area available to be degraded by enzymes and / or organisms, making this process highly efficient in terms yields (of both monomeric and oligomeric sugars as well as fermentation products) and more cost-effective.

[0194] The embodiments described herein are to be understood to be exemplary and numerous modification and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the claims appended hereto, the invention may be practiced otherwise than as specifically disclosed herein.

Claims

CLAIMS1. A method of converting railroad ties into cellulose for use in a fermentation process; wherein said method comprising the steps of: providing a railroad tie contaminated with at least one compound selected from the group consisting of: creosote; cresol; and a tar product; processing the railroad tie into processed particles of a size ranging of up to 6 inches; providing an acidic composition having a pH of less than 1, said acidic composition selected from the group consisting of: composition A; composition B; composition C; composition D; composition E; composition F; composition G; composition H; composition I; and composition J; wherein said composition A comprises: o sulfuric acid; o a compound comprising an amine moiety and a sulfonic acid moiety; and o a peroxide; and wherein sulfuric acid, said compound comprising an amine moiety and a sulfonic acid moiety and said peroxide are present in a molar ratio of no less than 1: 1: 1; wherein said composition B comprises: o sulfuric acid; o a compound comprising an amine moiety; o a compound comprising a sulfonic acid moiety; and o a peroxide; wherein sulfuric acid and said a compound comprising an amine moiety and said compound comprising a sulfonic acid moiety are present in a molar ratio of no less than 1: 1: 1; wherein said composition C comprises: o an alkylsulfonic acid; and o a peroxide; wherein said alkylsulfonic acid and said peroxide are present in a molar ratio of no less than 1: 1; wherein said composition D comprises: o sulfuric acid; o a heterocyclic compound; and o a peroxide; and wherein sulfuric acid and said a heterocyclic compound; are present in a molar ratio of no less than 1: 1; wherein said composition E comprises: o sulfuric acid;o a modifying agent comprising a compound containing an amine group; and o a peroxide; and wherein sulfuric acid and said compound containing an amine group; are present in a molar ratio of no less than 1: 1; wherein said composition F comprises: o sulfuric acid; o a modifying agent comprising an alkane sulfonic acid and o a peroxide; and wherein sulfuric acid and said alkanesulfonic acid are present in a molar ratio of no less than 1: 1; wherein said composition G comprises: o sulfuric acid; o a substituted aromatic compound; and o a peroxide; and wherein sulfuric acid and said substituted aromatic compound; are present in a molar ratio of no less than 1: 1; wherein said composition H comprises: o sulfuric acid; o a modifying agent comprising an arylsulfonic acid; o a peroxide; and o optionally, a compound containing an amine group ; wherein sulfuric acid and said a arylsulfonic acid; are present in a molar ratio of no less than 1: 1; wherein said composition I comprises: o sulfuric acid; o a heterocyclic compound; o an alkanesulfonic acid and o a peroxide; and wherein sulfuric acid and said a heterocyclic compound; are present in a molar ratio of no less than 1: 1; wherein said composition J comprises: o sulfuric acid; o a carbonyl-containing nitrogenous base compound; and o a peroxide; and wherein sulfuric acid and said a carbonyl-containing nitrogenous base compound; are present in a molar ratio of no less than 1: 1; providing an alcohol selected from the group consisting of Ci-Ce linear alcohol; C’s-C,, branched alcohol and mixtures thereof; exposing said processed particles to said acidic composition and said alcohol for a period of time sufficient to delignify said processed particles and yield a contaminated cellulose portioncomprising at least one contaminant selected from the group consisting of: creosote; a creosote degradation product; a cresol degradation product; a tar-derivative product; a tar-derivative degradation product; and a liquid portion comprising lignin; lignin depolymerization products; creosote degradation products; cresol degradation products; removing said liquid portion; washing the contaminated cellulose portion with an organic solvent thereby obtaining a washed cellulose; separating said washed cellulose from said organic solvent; recovering said washed cellulose portion, wherein said washed cellulose portion contains less than 50% of the initial content of creosote, cresol, and / or a tar product; wherein said washed cellulose contains amounts of said at least one contaminant which do not prevent cellulose fermentation into a value added product.

2. The method according to claim 1, wherein said creosote degradation product is selected from the group consisting of: uncondensed polycylic aromatic hydrocarbons, small chain acids and diacids.

3. The method according to claim 1, wherein said cresol degradation product is selected from the group consisting of: small chain acids and diacids.

4. The method according to claim 1 , wherein said a tar-derivative degradation product is selected from the group consisting of: polycyclic aromatic hydrocarbons.

5. A method of converting railroad ties into cellulose for use in fermentation into at least one value- added product; wherein said method comprising the steps of: providing a railroad tie contaminated with at least one compound selected from the group consisting of: creosote; cresol; and a tar product; processing said railroad tie into processed particles of a size ranging of up to 6 inches; providing a reactive phase of pH less than 1, said reactive phase comprising: o water; and o an acidic composition having apH of less than 1, said acidic composition selected from the group consisting of: composition A; composition B; composition C; composition D; composition E; composition F; composition G; composition H; composition I; and composition J; wherein said composition A comprises:o sulfuric acid; o a compound comprising an amine moiety and a sulfonic acid moiety; and o a peroxide; and wherein sulfuric acid, said compound comprising an amine moiety and a sulfonic acid moiety and said peroxide are present in a molar ratio of no less than 1: 1:1; wherein said composition B comprises: o sulfuric acid; o a compound comprising an amine moiety; o a compound comprising a sulfonic acid moiety; and o a peroxide; wherein sulfuric acid and said a compound comprising an amine moiety and said compound comprising a sulfonic acid moiety are present in a molar ratio of no less than 1:1: 1; wherein said composition C comprises: o an alkylsulfonic acid; and o a peroxide; wherein said alkylsulfonic acid and said peroxide are present in a molar ratio of no less than 1: 1; wherein said composition D comprises: o sulfuric acid; o a heterocyclic compound; and o a peroxide; and wherein sulfuric acid and said a heterocyclic compound; are present in a molar ratio of no less than 1: 1; wherein said composition E comprises: o sulfuric acid; o a modifying agent comprising a compound containing an amine group; and o a peroxide; and wherein sulfuric acid and said compound containing an amine group; are present in a molar ratio of no less than 1: 1; wherein said composition F comprises: o sulfuric acid; o a modifying agent comprising an alkane sulfonic acid and o a peroxide; and wherein sulfuric acid and said alkanesulfonic acid are present in a molar ratio of no less than 1: 1; wherein said composition G comprises: o sulfuric acid; o a substituted aromatic compound; ando a peroxide; and wherein sulfuric acid and said substituted aromatic compound; are present in a molar ratio of no less than 1: 1; wherein said composition H comprises: o sulfuric acid; o a modifying agent comprising an arylsulfonic acid; o a peroxide; and o optionally, a compound containing an amine group ; wherein sulfuric acid and said a arylsulfonic acid; are present in a molar ratio of no less than 1: 1; wherein said composition I comprises: o sulfuric acid; o a heterocyclic compound; o an alkanesulfonic acid and o a peroxide; and wherein sulfuric acid and said a heterocyclic compound; are present in a molar ratio of no less than 1: 1; wherein said composition J comprises: o sulfuric acid; o a carbonyl-containing nitrogenous base compound; and o a peroxide; and wherein sulfuric acid and said a carbonyl-containing nitrogenous base compound; are present in a molar ratio of no less than 1: 1; providing an alcohol selected from the group consisting of Ci-Ce linear alcohol; C’s-C,, branched alcohol and mixtures thereof; providing a holding phase, said holding phase comprising an organic solvent which does not react with the aqueous acidic composition; combining said reactive phase and holding phase to form a reaction mixture; exposing said processed particles to said acidic composition for a period of time sufficient to delignify said processed particles and yield a contaminated cellulose portion comprising at least one contaminant selected from the group consisting of: creosote; a creosote degradation product; a cresol degradation product; a tar-derivative product; a tar-derivative degradation product; and a liquid portion comprising lignin; lignin depolymerization products; creosote degradation products; cresol degradation products.

6. The method according to claim 5, wherein said method further comprises the steps of : removing said liquid portion; washing the contaminated cellulose portion with an organic solvent;separating a washed cellulose from said organic solvent; recovering said washed cellulose portion; optionally, washing said washed cellulose portion with water and neutralizing it to a pH ranging from 5 to 9, thereby obtaining a neutralized cellulose portion; exposing said neutralized cellulose portion to an enzyme blend to produce a hydrolysate comprising sugars obtained from the hydrolysis of cellulose and hemicellulose, optionally, fermenting said hydrolysate with a fermenting organism to produce value-added products.

7. The method according to claim 5 or 6, wherein said method further comprises a step of preextraction by exposing said processed particles to a solvent capable of dissolving creosote.

8. The method according to claim 5 where the reactive phase and the holding phase are present in a weight ratio ranging from 2: 1 to 1:2.

9. The method according to any one of claims 5 to 8 where the reactive phase and the holding phase are present in a weight ratio ranging from 1.5: I to 1: 1.5.

10. The method according to any one of claims 5 to 9 where the holding phase comprises a solvent selected from the group consisting of: Ci-Ce linear alcohol; C’s-C,, branched alcohol and mixtures thereof.

11. The method according to any one of claims 5 to 9 where the holding phase comprises a solvent selected from the group consisting of: ethyl acetate; propyl acetate; butyl acetate; and combinations thereof.

12. The method according to any one of claims 5 to 11 where the sulfuric acid and the source of peroxide are present in a molar ratio ranging from 3: 1 to 1:3.

13. The method according to any one of claims 5 to 11 where the sulfuric acid and the modifying agent are present in a molar ratio ranging from 10: 1 to 1: 10.

14. The method according to any one of claims 5 to 11 where the sulfuric acid and the modifying agent are present in a molar ratio ranging from 3: 1 to 1:3.

15. The method according to any one of claims 5 to 11 where the sulfuric acid and the modifying agent are present in a molar ratio ranging from 3 : 1 to 1: 1.

16. The method according to claim 10 where the alcohol is selected from the group consisting of: methanol; ethanol; n-propanol; isopropanol; n-butanol; and isobutanol.

17. The method according to any one of claims 10 and 16 where the alcohol and the sulfuric acid are present in a molar ratio ranging from 1 : 1 (alcohol : sulfuric acid) to 10: 1 (alcohol : sulfuric acid).

17. The method according to any one of claims 10 and 16 where the alcohol and the sulfuric acid are present in a molar ratio ranging from 3: 1 (alcohol : sulfuric acid) to 5: 1 (alcohol : sulfuric acid).

18. The method according to any one of claims 5 to 17 where the peroxide and the sulfuric acid are present in a molar ratio ranging from 1.5: 1 (peroxide: sulfuric acid) to 1: 10 (peroxide: sulfuric acid).

19. The method according to any one of claims 5 to 17 where the peroxide and the sulfuric acid are present in a molar ratio ranging from 1:3 (peroxide: sulfuric acid) to 1:7 (peroxide: sulfuric acid).

20. The method according to any one of claims 5 to 17 where the peroxide and the sulfuric acid are present in a molar ratio of approximately 1:5 (peroxide: sulfuric acid).

21. The method according to any one of claims 5 to 20 where the peroxide and the alcohol are present in a molar ratio ranging from 1: 1 (peroxide: alcohol) to 1:20 (peroxide: alcohol).

22. The method according to any one of claims 5 to 20 where the peroxide and the alcohol are present in a molar ratio ranging from 1:5 (peroxide: alcohol) to 1: 15 (peroxide: alcohol).

23. The method according to any one of claims 5 to 20 where the peroxide and the alcohol are present in a molar ratio ranging from 1:7 (peroxide: alcohol) to 1: 10 (peroxide: alcohol).

24. The method according to any one of claims 1 to 23 where the high value added product is bioethanol.

25. The method according to any one of claims 1 to 23 where the high value added product is methane.

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