Method for depolymerizing lignocellulosic biomass

Abstract

A method for depolymerizing lignocellulosic biomass, comprising the following steps: (a) depolymerizing lignocellulosic biomass under supercritical conditions in the presence of at least one alcohol having 1 to 5 carbon atoms, preferably 1 to 2 carbon atoms, at a temperature of 200°C to 300°C, preferably 220°C to 295°C, at a pressure of 40 bar to 170 bar, preferably 50 bar to 150 bar, at a lignocellulosic biomass / alcohol ratio of 0.1 to 1, preferably 0.15 to 0.8 wt / wt (w / w), for a time of 5 to 150 minutes, preferably 10 to 130 minutes, to obtain: (i) a mixture comprising a liquid phase and a solid phase, the liquid phase comprising depolymerized lignocellulosic biomass and at least one alcohol, the solid phase comprising carbon residue (“char”), depolymerized lignocellulosic biomass, and optionally undepolymerized lignocellulosic biomass; (ii) an optional gas phase; (b) A liquid phase comprising depolymerized lignocellulosic biomass and at least one alcohol is separated from the mixture (i) obtained in step (a) to obtain: (iii) a liquid phase comprising depolymerized lignocellulosic biomass and at least one alcohol; (iv) a solid phase comprising carbon residue (“char”), depolymerized lignocellulosic biomass, and optionally undepolymerized lignocellulosic biomass; (c) the liquid phase (iii) comprising depolymerized lignocellulosic biomass and at least one alcohol obtained in step (b) is purified to obtain: (v) depolymerized lignocellulosic biomass; and (vi) at least one alcohol. The depolymerized lignocellulosic biomass obtained by the above method can be advantageously used as, for example, an antioxidant or UV protectant in biofuels, which can be used as is or blended with other fuels in automotive or aviation diesel engines. Furthermore, the depolymerized lignocellulosic biomass obtained by the above method can be advantageously used as an antioxidant in, for example, biological feedstocks (e.g., vegetable oils and animal or vegetable fats) to slow their rancidity during transport and storage.

Description

[0001] This invention relates to a method for depolymerizing lignocellulose biomass.

[0002] More specifically, the present invention relates to a method for depolymerizing lignocellulose biomass, comprising the following steps: (a) depolymerizing lignocellulose biomass under supercritical conditions of specific temperature, pressure and time conditions in the presence of at least one alcohol; (b) separating a liquid phase containing the depolymerized lignocellulose biomass and at least one alcohol from the mixture obtained in step (a); and (c) purifying the liquid phase containing the depolymerized lignocellulose biomass and at least one alcohol obtained in step (b) to obtain the depolymerized lignocellulose biomass and at least one alcohol.

[0003] The depolymerized lignocellulosic biomass obtained by the above method can be advantageously used as, for example, an antioxidant or UV stabilizer, particularly as an antioxidant or UV stabilizer in biofuels, which can be used as is or blended with other fuels in automotive or aviation diesel engines. Furthermore, the depolymerized lignocellulosic biomass obtained by the above method can be advantageously used as an antioxidant in, for example, biological feedstocks (e.g., vegetable oils and animal or vegetable fats) to slow their rancidity during transportation and storage.

[0004] This invention also relates to depolymerized lignocellulose biomass, which has the specific features described below.

[0005] Furthermore, the present invention also relates to the use of the depolymerized lignocellulosic biomass as an antioxidant or UV stabilizer, particularly as an antioxidant or UV stabilizer in biofuels, which can be used as is or mixed with other fuels in automobile or aviation diesel engines.

[0006] Furthermore, the present invention also relates to the use of the depolymerized lignocellulose biomass as an antioxidant in biological feedstocks (e.g., vegetable oils and animal or vegetable fats).

[0007] Generally, biomass is defined as any substance having an organic, plant, or animal matrix that can be used to produce agricultural soil conditioners or for energy purposes, such as as a feedstock for the production of biofuels and / or biocombustion, or as a component that can be added to fuels and / or combustion. Therefore, biomass encompasses not only products cultivated specifically for energy purposes, but also all products of agricultural and forestry cultivation, including residues from agricultural and forestry treatments, agricultural food product waste for human consumption or livestock, untreated residues from the wood and paper industries, and all organic products generated by the biological activities of animals and humans (e.g., organic products contained in municipal waste).

[0008] As mentioned above, among its many potential uses, biomass can serve as a source of renewable energy, replacing traditional fossil-based feedstocks typically used to produce combustibles. Lignocellulosic biomass is particularly useful for this purpose.

[0009] Lignocellulosic biomass is a complex structure comprising three main components: cellulose, hemicellulose, and lignin. Their relative amounts vary depending on the type of lignocellulosic biomass used. For example, in the case of plants, these amounts vary depending on the plant species and age.

[0010] Cellulose is the main component of lignocellulose biomass and typically exists at 30% to 60% by weight relative to the total weight of lignocellulose biomass. Cellulose is composed of glucose molecules (approximately 500 to 10,000 units) linked together by glycosidic bonds. The formation of hydrogen bonds between the chains leads to the formation of crystalline domains, which gives plant fibers strength and elasticity. In nature, it exists only in its pure state in annual plants such as cotton and flax, while in woody plants, it is always accompanied by hemicellulose and lignin.

[0011] Hemicellulose, typically present in amounts ranging from 10% to 40% by weight relative to the total weight of lignocellulose biomass, exists as a mixed, relatively short (10 to 200 molecules) and branched polymer composed of sugars with six carbon atoms (glucose, mannose, galactose) and sugars with five carbon atoms (xylose, arabinose). The presence of hemicellulose plays a role in many important properties of plant fibers; a major role is that, in the presence of water, hemicellulose promotes the absorption of these fibers, causing them to swell. Hemicellulose also possesses adhesive properties, thus readily binding or keratinizing when dehydrated, resulting in the plant fibers becoming rigid and absorbing less efficiently.

[0012] Furthermore, lignin typically exists in amounts ranging from 10% to 30% by weight relative to the total weight of lignocellulosic biomass. Its primary function is to bind various plant fibers together, thereby giving plants compactness and strength, and also providing protection against insects, pathogens, damage, and ultraviolet radiation.

[0013] From a circular economy perspective, lignocellulosic biomass represents a high-potential class of materials that can be used to industrialize a variety of products from renewable resources. This class of materials is produced in the form of byproducts from large-scale processing (such as those from the food and paper industries, and byproducts from the agricultural sector), and is therefore generally readily available and inexpensive. Furthermore, these materials do not compete with products cultivated for human food, although they do compete at least in part with products cultivated for animal feed and the use of arable land.

[0014] Lignocellulosic biomass can be categorized into primary biomass, waste biomass, and biomass derived from energy crops. Primary biomass includes all naturally occurring terrestrial plants, such as trees, shrubs, and grasses. Waste biomass consists of low-value products from various industries (e.g., agriculture, forestry, and papermaking). Biomass derived from energy crops comes from the cultivation of plants that, as mentioned above, do not compete with crops intended for human consumption. High-yield lignocellulosic biomass is used as feedstock specifically for the production of second-generation biofuels.

[0015] To date, lignocellulosic biomass conversion technologies exist, which include fractionation of lignocellulosic biomass to obtain fermentable sugars, such as those derived from the hydrolysis of cellulose and hemicellulose, which can then be used to produce second-generation biofuels (particularly bioethanol), or catalytic or non-catalytic thermal treatment to obtain crude bio-oils, which must then be refined. The lignin obtained from these processes is typically considered a secondary waste product and is treated, for example, by incineration.

[0016] For example, US patent application US 2010 / 330638 relates to a method for producing ethanol from lignocellulosic biomass using a fed-batch system, the method comprising the steps of: a) treating an aqueous solution of lignocellulosic biomass of up to 15% [dry biomass weight / total biomass weight (biomass plus water)] with a dilute ammonium hydroxide solution at a temperature above 100°C for a sufficient duration to increase the surface area of ​​the biomass for enzymatic hydrolysis; b) washing the treated biomass with water; c) removing at least 40% of the water from the treated and washed biomass; d) contacting the dehydrated biomass with a saccharifying enzyme under conditions conducive to the production of fermentable sugars; e) milling the biomass after step (a) and before step (d); f) repeating steps a) through e) at most twice; and g) contacting the fermentable sugars with microorganisms capable of producing ethanol. The above method is claimed to optimize the hydrolysis of biomass to sugars and produce ethanol with high titers.

[0017] US Patent Application US 2016 / 273010 relates to a method for processing lignocellulosic biomass, comprising: providing lignocellulosic biomass and at least one solvent; providing a mixer and heating it to a temperature of 100°C to 300°C; adding the biomass and solvent to the mixer; mixing the biomass and solvent to obtain a slurry; and melting and compounding the slurry under shear and heating for a sufficient time to break the interpolymeric and intrapolymeric bonds of the biomass. Preferably, the solvent is a polyol, more preferably glycerol. The above method is claimed to provide materials that can be converted into fermentable sugars in high yields, thereby maintaining high molecular weight non-condensation lignin that can be recovered in good yields.

[0018] International patent application WO 2019 / 072386 relates to a method for treating lignocellulosic materials, comprising:

[0019] 1) Provide and optionally prepare a process flow A comprising lignocellulose material;

[0020] 2) The process stream A containing lignocellulose material is subjected to a pulping step and a separation step to obtain two independent process streams: at least one process stream A derived from cellulose, and at least one process stream A derived from lignin.

[0021] 3) Further process the at least one cellulose-derived process stream A, optionally subjecting the cellulose-derived process stream A to one or more of the following sub-steps: washing, delignination, bleaching, chemical treatment, paper or paperboard manufacturing, or any combination thereof;

[0022] 4) subject the at least one lignin-derived process stream A to at least one separation and / or purification step to obtain at least one process stream A containing modified lignin-derived components;

[0023] 5) Perform a chemical decomposition step on the process stream A containing the at least one lignin-derived component, wherein the chemical decomposition step includes oxidative pyrolysis, reductive pyrolysis or electro-oxidation of the modified lignin-derived component, thereby generating at least one lignin-derived process stream A containing a lignin-derived low molecular weight aromatic compound.

[0024] 6) Perform separation and / or purification steps on at least one lignin-derived process stream A containing a modified lignin-derived compound to obtain at least one lignin-derived process stream A containing a lignin-derived low molecular weight aromatic compound.

[0025] The above method is said to enhance both cellulose and lignin.

[0026] International patent application WO 2008 / 144878 relates to a modular process for fractionating lignocellulosic raw materials into different components using an organic solvent (organosolv) and subsequently processing these components, the modular process comprising:

[0027] - A first processing module comprising a series of steps for receiving, physically screening and physicochemically decomposing lignocellulose raw materials by means of separately supplied organic solvents, thereby extracting components therefrom and separating these components into a cellulose solid fraction and a first liquid fraction;

[0028] - A second processing module comprising a second series of steps for producing ethanol and various lignin derivatives from the solid cellulose fraction for use as fuel;

[0029] - A third processing module comprising a third series of steps, the third series of steps including at least a first step, namely separating a first liquid portion into a second solid portion containing multiple types of second-class lignin derivatives and a first filtrate; a second step, namely separating the first filtrate into a third solid portion containing multiple types of third-class lignin derivatives and a second filtrate; a third step, namely separating furfural from the filtrate; and a fourth step, namely recovering a portion of the organic solvent from the filtrate by distillation to obtain a first distillate.

[0030] - A fourth processing module, comprising a fourth series of steps for separating the first distillate into at least one fraction containing acetic acid, a plurality of fourth-order lignin derivatives, monosaccharide syrup, and solid waste.

[0031] The aforementioned method is said to be able to provide components that can be selectively processed, controlled, and manipulated.

[0032] International patent application WO 2012 / 109241 relates to the production of C from biomass. 8+ Methods involving compounds, including:

[0033] (i) Provide a reagent flow containing a first reagent and a second reagent.

[0034] The first reagent comprises one or more having the general formula C x H y O z The molecule, wherein the average oxygen-to-carbon ratio of the first reagent is 0.2 to 1.0, and wherein x = 2-12 carbon atoms and z = 1-12 oxygen atoms,

[0035] The second reagent comprises one or more having the general formula C p H r O s The molecule, wherein the average oxygen-to-carbon ratio of the second reagent is 0.2 or less, and wherein p = 2-7 ​​carbon atoms and s = 0-1 oxygen atoms,

[0036] Wherein the number of carbon atoms in the reagent stream originating from the first reagent is greater than 10% of the total number of carbon atoms in the reagent stream, and the number of carbon atoms in the reagent stream originating from the second reagent is greater than 10% of the total number of carbon atoms in the reagent stream, and

[0037] (ii) Catalytically reacting the reagent stream with hydrogen in the presence of an acid condensation catalyst to produce a product containing water and various C4 compounds. 8+ The product stream of the compound, the C 8+ The compounds are selected from the group consisting of: C 8+ Alkanes, C 8+ Olefins, C 8+ Cycloalkanes, C8+ Cycloolefins, C 8+ alcohols, C 8+ Ketones, aryl groups, molten aryl groups, oxidized aryl groups, oxidized molten aryl groups, and mixtures thereof, wherein the acid condensation catalyst comprises an acid support or a heterogeneous acid catalyst, the heterogeneous acid catalyst comprising a metal selected from the group consisting of: Pd, Pt, Cu, Co, Ru, Cr, Ni, Ag, alloys thereof, and combinations thereof.

[0038] The aforementioned method is said to be able to convert biomass and biomass-derived feedstocks into large quantities of heavy hydrocarbons for use as jet fuel and diesel, or as heavy oil and / or combustible fuel for lubrication applications.

[0039] International patent application WO 2021 / 209555 relates to a method for producing bio-crude oil, which includes the following steps:

[0040] (i) Provide lignocellulose biomass, and

[0041] (ii) The biomass is subjected to thermochemical treatment at a temperature of 250°C to 450°C for a residence time of 1 minute to 120 minutes, wherein the biomass is in the form of a slurry formed from recycled oil obtained by a similar pre-thermochemical treatment of biomass, and a short-chain alcohol is added to the slurry in an amount of 2% to 150% of the dry weight of the slurry, wherein the ratio of biomass to recycled oil is 1:1 to 1:5 w / w, and the ratio of biomass to added alcohol is 1:9 to 5:1 w / w.

[0042] The above method is said to reduce the formation of carbon residues (“char”) and increase the yield of crude bio-oil.

[0043] Japanese Patent Application JP 2001 / 205070 relates to a method for obtaining a biomass-derived composition, the method comprising treating one, two, or more components selected from the group consisting of lignocellulosic biomass, cellulose biomass, nitrogen-containing polysaccharides, and protein-based biomass in one or more organic solvents under supercritical or subcritical conditions. Preferably, the organic solvent used is an alcohol, more preferably methanol. It is claimed that the above method can provide a biomass composition in a simple and efficient manner by limiting the formation of insoluble products in the solvent used.

[0044] The aforementioned methods for depolymerizing lignocellulosic biomass primarily involve fractionation to obtain, for example, fermentable sugars commonly used in ethanol production and lignin, which is typically discarded, or catalytic or non-catalytic thermal treatment to obtain crude bio-oil, which requires further processing before use as fuel. None of these methods describe the possibility of obtaining depolymerized biomass that can be used as an additive, particularly as an antioxidant or UV protectant.

[0045] The problem faced by the applicant is to find a simple and universal method for depolymerizing lignocellulosic biomass, which does not involve fractionation of the lignocellulosic biomass, and / or the use of catalysts, and / or further processing of the final product obtained.

[0046] The applicant has now discovered a method for depolymerizing lignocellulose biomass, which allows for the acquisition of depolymerized lignocellulose biomass that can be used as an additive, particularly as an antioxidant or UV protectant. Specifically, the applicant has discovered a method for depolymerizing lignocellulose biomass comprising the following steps: (a) depolymerizing lignocellulose biomass under supercritical conditions of specific temperature, pressure, and time, in the presence of at least one alcohol; (b) separating a liquid phase containing the depolymerized lignocellulose biomass and at least one alcohol from the mixture obtained in step (a); and (c) purifying the liquid phase containing the depolymerized lignocellulose biomass and at least one alcohol obtained in step (b) to obtain the depolymerized lignocellulose biomass and at least one alcohol.

[0047] The above method offers many advantages. For example, the above method allows:

[0048] - Obtain high yields of depolymerized lignocellulosic biomass (i.e., yields of 25% to 90% by weight relative to the total weight of the depolymerized lignocellulosic biomass).

[0049] - Depolymerization is carried out at a temperature not exceeding 300°C;

[0050] - In the case of obtaining a gas phase, a low gas yield is obtained [the gas phase consists mainly of a mixture of hydrocarbons having 1 to 4 carbon atoms and a small amount of other gases (e.g., carbon monoxide (CO))] (the gas yield is less than or equal to 8% by weight relative to the total weight of the lignocellulosic biomass undergoing depolymerization).

[0051] - Recycling the solvent (i.e., the alcohol used in the depolymerization step) reduces solvent loss;

[0052] - Obtain low molecular weight depolymerized lignocellulose biomass [i.e., weight-average molecular weight (M...]] w ) less than or equal to 1200 and number average molecular weight (M n (less than or equal to 500 Daltons).

[0053] Furthermore, the above methods are easily scaled up at the industrial level due to the low or no gas yield, the possibility of operating with a high solids (i.e., biomass) / alcohol weight (w / w) ratio, alcohol recycling, and specific temperature and time conditions.

[0054] Furthermore, the above method enables the production of depolymerized lignocellulosic biomass, which can be advantageously used as an antioxidant or UV protectant in, for example, biofuels that can be used as is or blended with other fuels in automotive or aviation diesel engines. Additionally, the depolymerized lignocellulosic biomass obtained by the above method can advantageously serve as an antioxidant in, for example, biofuels such as vegetable oils and animal or plant fats, to slow their rancidity during transportation and storage.

[0055] Therefore, the present invention relates to a method for depolymerizing lignocellulose biomass, comprising the following steps:

[0056] (a) In the presence of at least one alcohol having 1 to 5 carbon atoms, preferably 1 to 2 carbon atoms, under supercritical conditions, at a temperature of 200°C to 300°C, preferably 220°C to 295°C, at a pressure of 40 bar to 170 bar, preferably 50 bar to 150 bar, at a lignocellulose biomass / alcohol ratio of 0.1 to 1, preferably 0.15 to 0.8 wt / w, the lignocellulose biomass is depolymerized for 5 to 150 minutes, preferably 10 to 130 minutes, to obtain:

[0057] (i) A mixture comprising a liquid phase and a solid phase, the liquid phase comprising depolymerized lignocellulose biomass and at least one alcohol, and the solid phase comprising carbon residue (“char”), depolymerized lignocellulose biomass and optionally undepolymerized lignocellulose biomass;

[0058] (ii) An optional gas phase;

[0059] (b) Separating the liquid phase containing depolymerized lignocellulose biomass and at least one alcohol from the mixture (i) obtained in step (a) yields:

[0060] (iii) A liquid phase comprising depolymerized lignocellulose biomass and at least one alcohol;

[0061] (iv) A solid phase comprising carbon residue (“char”), depolymerized lignocellulosic biomass, and optionally undepolymerized lignocellulosic biomass;

[0062] (c) The liquid phase (iii) obtained in step (b) containing depolymerized lignocellulose biomass and at least one alcohol is purified to obtain:

[0063] (v) Depolymerization of lignocellulose biomass;

[0064] (vi) At least one alcohol.

[0065] For the purposes of this specification and the foregoing claims, the definition of a numerical range always includes extreme values, unless otherwise stated.

[0066] For the purposes of this specification and the foregoing claims, the term "comprising" also includes the terms "consistently composed of" or "composed of".

[0067] According to a preferred embodiment of the present invention, the lignocellulosic biomass may be selected from, for example:

[0068] - Plants specifically cultivated for energy purposes, such as miscanthus, switchgrass (Panicum virgatum), and common reed (Arundo donax).

[0069] - Plants that are not specifically cultivated for energy purposes, such as sorghum (e.g., sorghum fiber).

[0070] - Waste, residues, and discarded products from agriculture, such as guayule, maize (e.g., maize stalks, maize cob), soybeans, cotton, flax, rapeseed, wheat (e.g., wheat stalks), rice (e.g., rice straw, rice hull, rice husk), sugarcane (e.g., sugarcane stalks, bagasse), and palm (e.g., palm leaves, palm trunks, palm hybrids, empty palm fruit clusters);

[0071] - Waste, residues and waste products from forestry, afforestation or timber processing, such as fir, poplar, alder and birch;

[0072] - Waste from agricultural food products intended for human consumption or livestock farming;

[0073] - Untreated residues from the paper industry;

[0074] - Waste collected from municipal solid waste sorting (e.g., municipal plant waste, paper);

[0075] - Algae, such as microalgae or macroalgae, especially macroalgae.

[0076] According to another preferred embodiment of the invention, the lignocellulosic biomass may be selected from, for example, waste products (oil cakes) derived from pressing plant seeds ("oilseed pressing panel cakes"), such as flax, rapeseed, soybean, sunflower, rapeseed, safflower, flax, rubber tree, castor bean, cotton, and sea cabbage.

[0077] It should be noted that when using oil cake, the depolymerized lignocellulosic biomass also contains fatty acid esters [e.g., fatty acid methyl esters (FAME)]. These fatty acid esters can be recovered from the depolymerized lignocellulosic biomass using processes known in the art (e.g., filtration, decantation, centrifugation, preferably filtration).

[0078] According to a preferred embodiment of the invention, the lignocellulosic biomass may be subjected to a preliminary grinding process before the depolymerization step (a). Preferably, the lignocellulosic biomass may be ground into particles with a diameter of 0.05 mm to 2.5 mm, more preferably 0.08 mm to 2 mm. Particularly preferred are particles with a diameter of less than 2 mm.

[0079] According to a preferred embodiment of the present invention, in the depolymerization step (a), the at least one alcohol may be selected from, for example, methanol, ethanol, propanol, butanol, pentanol or a mixture thereof; preferably selected from methanol, ethanol or a mixture thereof.

[0080] It should be noted that, for the purposes of the method of the present invention, the at least one alcohol used in the depolymerization step (a) may be of synthetic origin or of biological origin (bio-alcohol).

[0081] The optional gas phase (ii) obtained in the depolymerization step (a) of the aforementioned method is typically less than or equal to 8% by weight relative to the weight (dry weight) of the starting biomass. This gas phase consists primarily of a mixture of hydrocarbons having 1 to 4 carbon atoms and smaller amounts of other gases [e.g., carbon monoxide (CO)]. After separating this gas phase (which can be done, for example, by depressurization of a pressure vessel in which the depolymerization step (a) is carried out), the mixture (ii) obtained in the depolymerization step (a) is typically transported for further processing to increase its combustible organic content before being transported for further separation.

[0082] According to a preferred embodiment of the invention, the separation step (b) can be performed, for example, by filtration, decantation, or centrifugation.

[0083] According to a preferred embodiment of the invention, the solid phase (iv) comprising carbon residue (“char”), depolymerized lignocellulosic biomass, and optionally unpolymerized lignocellulosic biomass can be purified and separated (d) to obtain:

[0084] (vii) Liquid phase composed of undepolymerized lignocellulose biomass;

[0085] (viii) A solid phase comprising carbon residues (“char”) and optional undepolymerized lignocellulosic biomass.

[0086] According to a preferred embodiment of the invention, in step (d), purification can be carried out by washing with at least one alcohol, preferably with at least one alcohol used in the depolymerization step (a), and more preferably with methanol, ethanol, or a mixture thereof.

[0087] According to a preferred embodiment of the present invention, in step (d), separation can be performed by filtration, decantation, or centrifugation, preferably by filtration.

[0088] At the end of purification and separation step (d):

[0089] - The solid phase (viii) containing carbon residue (“char”) and optional undepolymerized lignocellulosic biomass can be dried, for example, in an oven to remove residual alcohols that can be recycled to the depolymerization step (a);

[0090] - The liquid phase consisting of depolymerized lignocellulose biomass can be combined with the liquid phase (iii) containing depolymerized lignocellulose biomass and at least one alcohol obtained in separation step (b), and the whole can be transported to purification step (c).

[0091] According to a preferred embodiment of the present invention, the purification step (c) can be performed by vacuum distillation.

[0092] At the end of purification step (c), alcohol (vi) (i.e., pure regenerated alcohol) can be fed into depolymerization step (a), while depolymerized lignocellulosic biomass (v), which contains monomers and oligomers of the three components derived from lignocellulosic biomass (i.e., cellulose, hemicellulose and lignin), can be used as is.

[0093] As described above, the present invention also relates to depolymerized lignocellulose biomass obtained by the above method.

[0094] Therefore, another subject of the present invention is a depolymerized lignocellulosic biomass that does not contain fatty acid esters, having the following characteristics:

[0095] - Weight-average molecular weight (M w Less than or equal to 1200 Daltons, preferably 150 Daltons to 1000 Daltons, and even more preferably 200 Daltons to 900 Daltons;

[0096] - Number average molecular weight (M n Less than or equal to 500 Daltons, preferably 80 to 400 Daltons, more preferably 100 to 300 Daltons;

[0097] - The percentage change of the H / C ratio of depolymerized lignocellulosic biomass relative to the H / C ratio of the starting lignocellulosic biomass is equal to an increase of at least 30%, preferably 35% to 250%, and even more preferably 50% to 230%.

[0098] - The percentage change of the H / O ratio of depolymerized lignocellulosic biomass relative to the H / O ratio of the starting lignocellulosic biomass is equal to an increase of at least 40%, preferably 45% to 500%, and even more preferably 60% to 450%.

[0099] - The percentage change in the O / C ratio of depolymerized lignocellulosic biomass relative to the O / C ratio of the starting lignocellulosic biomass is equal to at least a 20% reduction, preferably a 25% to a 250% reduction, and even more preferably a 30% to a 200% reduction.

[0100] Another subject of this invention is a depolymerized lignocellulosic biomass containing fatty acid esters, which has the following characteristics:

[0101] - Weight-average molecular weight (M w Less than or equal to 1200 Daltons, preferably 150 Daltons to 1000 Daltons, and even more preferably 200 Daltons to 900 Daltons;

[0102] - Number average molecular weight (M n Less than or equal to 400 Daltons, preferably 50 to 390 Daltons, more preferably 60 to 350 Daltons;

[0103] - The percentage change in the H / C ratio of depolymerized lignocellulosic biomass relative to the H / C ratio of the starting lignocellulosic biomass is equal to at least a 2% reduction, preferably a 4% reduction to a 200% reduction, or even more preferably a 6% reduction to a 180% reduction.

[0104] - The percentage change of the H / O ratio of depolymerized lignocellulosic biomass relative to the H / O ratio of the starting lignocellulosic biomass is equal to at least a 5% reduction, preferably a 10% reduction to a 200% reduction, or even more preferably a 20% reduction to a 150% reduction.

[0105] - The percentage change in the O / C ratio of depolymerized lignocellulosic biomass relative to the O / C ratio of the starting lignocellulosic biomass is equal to an increase of at least 30%, preferably 35% to 350%, and even more preferably 40% to 280%.

[0106] As described above, the present invention relates to the use of depolymerized lignocellulose biomass as an antioxidant or UV protectant.

[0107] Therefore, another subject of the present invention is the use of depolymerized lignocellulosic biomass as an antioxidant or UV stabilizer, preferably as an antioxidant or UV stabilizer in biofuels that can be used as is or mixed with other fuels in automobile or aviation diesel engines.

[0108] Another subject of the present invention is the use of depolymerized lignocellulose biomass as an antioxidant in biosources such as vegetable oils and animal or plant fats.

[0109] Now refer to the report below. Figure 1 The invention will be described in more detail through the implementation scheme.

[0110] Figure 1 An embodiment of the method according to the invention is described. For this purpose, lignocellulosic biomass (1) (e.g., fir sawdust) is depolymerized in the presence of at least one alcohol (e.g., methanol, ethanol) in a depolymerization step (2) to obtain an optional gas phase (3) and a mixture (4), said mixture (4) comprising: a liquid phase containing depolymerized lignocellulosic biomass and at least one alcohol, and a solid phase containing carbon residue (“char”) and optional undepolymerized lignocellulosic biomass. The mixture (4) is conveyed to a separation step (5) (e.g., by filtration) to obtain a solid phase (6) containing carbon residue (“char”), depolymerized lignocellulosic biomass and optional undepolymerized lignocellulosic biomass, and a liquid phase (7) containing depolymerized lignocellulosic biomass and at least one alcohol {the depolymerized lignocellulosic biomass optionally contains fatty acid esters [e.g., fatty acid methyl ester (FAME)]}. The solid phase (6) is purified and separated (8) to obtain a liquid phase (10) consisting of depolymerized lignocellulosic biomass and a solid phase (9) containing carbon residue (“char”) and optionally undepolymerized lignocellulosic biomass. The liquid phase (10) may be combined with a liquid phase (7) containing depolymerized lignocellulosic biomass and at least one alcohol {the depolymerized lignocellulosic biomass optionally contains fatty acid esters [e.g., fatty acid methyl ester (FAME)]}. The solid phase (9) may be dried in an oven to remove all alcohols, which may then be recycled to the depolymerization step (2). Figure 1 (Not shown in the image). After being combined with the liquid phase (10), the liquid phase (7) is transported to the purification stage (11) to obtain at least one alcohol (13) and depolymerized lignocellulosic biomass (12) to be recycled to the depolymerization step (2).

[0111] To better understand and put the invention into practice, some illustrative and non-limiting embodiments of the invention are reported below.

[0112] Analysis and characterization methods

[0113] Use the analytical and characterization methods reported below.

[0114] Determination of molecular weight

[0115] The molecular weight of the depolymerized lignocellulose biomass obtained in the following examples was determined by gel permeation chromatography (GPC) on an Agilent 1100 GPC using two PFGM (PSS) columns connected in series and linked in series with an Agilent 1100 VWD / UV detector (operating at wavelengths from 200 nm to 300 nm), which was then connected to an RI detector, using hexafluoro-2-propanol (HFIP) as the eluent. The depolymerized lignocellulose biomass sample obtained in the examples reported below was diluted in hexafluoro-2-propanol (HFIP) at a concentration of approximately 5 mg / mL. The sample was then filtered through a 0.2 nm polytetrafluoroethylene (PTFE) filter and then inserted for analysis. The analysis was performed at 40 °C at a flow rate of 1 mL / min for approximately 40 minutes.

[0116] Weight-average molecular weight (M w Number-average molecular weight (M) n ) and the multi-dispersion index (i.e., M) w / M n The ratio was evaluated using the polyethylene terephthalate (PET) standard.

[0117] The weight-average molecular weight (M) of the depolymerized lignocellulose biomass samples obtained in the examples reported below is... w ) and number-average molecular weight (M n ) is considering 10 0 Up to 10 4 The molecular weight was determined based on the reference molecular weight range.

[0118] Determination of H / C ratio, H / O ratio and O / C ratio

[0119] Therefore, elemental analysis of CHNS(O) was performed using an ICP-OES analyzer (ICAP 6500 DV Thermo Fisher Scientific, Waltham, MA, USA). This analysis allows for the determination of the amounts of carbon (C), hydrogen (H), nitrogen (N), sulfur (S), and oxygen (O) present in the sample.

[0120] After thoroughly washing and drying all instruments with ethanol, proceed with the following steps.

[0121] The sample to be analyzed (2 mg) was placed in a tin crucible and then sealed to ensure the sample was well contained inside. The crucible was then placed in the aforementioned elemental analyzer, and the percentages of C, H, N, and S were obtained using the connected software. From these values, the H / C ratio, H / O ratio, and H / O ratio were obtained.

[0122] Example 1

[0123] Production of depolymerized lignocellulose biomass

[0124] 30 g of fir wood chips (particle diameter < 2 mm) and 150 g of methanol [lignocellulosic biomass / methanol ratio (w / w) equal to 0.2] were placed in a 500 ml reactor: the mixture was kept at 250 °C and 94 bar for 120 minutes with stirring to obtain a mixture comprising a liquid phase and a solid phase, wherein the liquid phase comprises depolymerized lignocellulosic biomass and methanol, and the solid phase comprises carbon residue (“char”), depolymerized lignocellulosic biomass and undepolymerized lignocellulosic biomass.

[0125] The mixture was separated by filtration to obtain a solid phase (73.5 g) containing carbon residue (“char”), depolymerized lignocellulosic biomass and undepolymerized lignocellulosic biomass, and a liquid phase (106.5 g) containing depolymerized lignocellulosic biomass and methanol.

[0126] The solid phase was then purified and separated. For this purpose, the solid phase was placed in a 250 ml beaker equipped with a magnetic stirrer, and 100 g of pure methanol was added. The mixture was then kept at room temperature (25°C) for 15 minutes with stirring. Finally, the resulting mixture was separated by filtration twice to obtain a liquid phase (100 g) consisting of depolymerized lignocellulosic biomass and a solid phase containing carbon residues (“char”) and undepolymerized lignocellulosic biomass. This liquid phase was then combined with the aforementioned liquid phase containing depolymerized lignocellulosic biomass and methanol. The solid phase was then dried in an oven at 85°C and 10 mbar for 10 hours to completely remove residual methanol; the final amount of dried solid was approximately 22 g.

[0127] A liquid phase (206.5 g) containing depolymerized lignocellulosic biomass and methanol was evaporated for 30 minutes in a rotary evaporator operating at 650 mbar and 85°C to obtain depolymerized lignocellulosic biomass (approximately 8 g - yield 26.67%) and methanol (198.5 g), the methanol of which can be recycled to the depolymerization step.

[0128] The molecular weight, H / C ratio, H / O ratio, and O / C ratio of the depolymerized lignocellulose biomass were determined as described above.

[0129] The results obtained are as follows:

[0130] - Weight-average molecular weight (M w The value is 700 Daltons.

[0131] - Number average molecular weight (M n The value is 270 Daltons;

[0132] - H / C ratio equals 0.18 (starting lignocellulosic biomass H / C ratio equals 0.09);

[0133] - H / O ratio equals 0.35 (initial lignocellulosic biomass H / O ratio equals 0.09);

[0134] - O / C ratio equals 0.52 (O / C ratio of initial lignocellulose biomass equals 0.98).

[0135] Example 2

[0136] Production of depolymerized lignocellulose biomass

[0137] 30 g of fir wood chips (particle diameter < 2 mm) and 150 g of ethanol [lignocellulosic biomass / ethanol ratio (w / w) equal to 0.2] were placed in a 500 ml reactor. The whole mixture was maintained at 250 °C and 72 bar for 120 minutes with stirring to obtain a gas phase (about 0.9 g) removed by vacuum and a mixture comprising a liquid phase and a solid phase, wherein the liquid phase comprises depolymerized lignocellulosic biomass and ethanol, and the solid phase comprises carbon residue (“char”), depolymerized lignocellulosic biomass and undepolymerized lignocellulosic biomass.

[0138] The mixture was separated by filtration to obtain a solid phase (44.1 g) containing carbon residue (“char”), depolymerized lignocellulosic biomass and undepolymerized lignocellulosic biomass, and a liquid phase (135 g) containing depolymerized lignocellulosic biomass and ethanol.

[0139] Subsequently, the solid phase was purified and separated. For this purpose, the solid phase was placed in a 250 ml beaker equipped with a magnetic stirrer, and 100 g of pure ethanol was added. The mixture was then kept at room temperature (25°C) for 15 minutes with stirring. Finally, the resulting mixture was separated by filtration twice to obtain a liquid phase (100 g) consisting of depolymerized lignocellulosic biomass and a solid phase containing carbon residue (“char”) and undepolymerized lignocellulosic biomass. This liquid phase was then combined with the liquid phase containing depolymerized lignocellulosic biomass and ethanol. The solid phase was then dried in an oven at 85°C and 10 mbar for 10 hours to completely remove residual ethanol; the final amount of dried solid was approximately 22 g.

[0140] A liquid phase (235 g) containing depolymerized lignocellulose biomass and methanol was evaporated for 30 minutes in a rotary evaporator operating at 650 mbar and 85°C to obtain depolymerized lignocellulose biomass (approximately 7 g - yield 23.33%) and ethanol (228 g), the ethanol of which can be recycled to the depolymerization step.

[0141] The molecular weight, H / C ratio, H / O ratio, and O / C ratio of the depolymerized lignocellulose biomass were determined as described above.

[0142] The results obtained are as follows:

[0143] - Weight-average molecular weight (M w The value is 780 Daltons;

[0144] - Number average molecular weight (M n The value is 250 Daltons;

[0145] - H / C ratio equals 0.18 (starting lignocellulosic biomass H / C ratio equals 0.09);

[0146] - H / O ratio equals 0.35 (initial lignocellulosic biomass H / O ratio equals 0.09);

[0147] - O / C ratio equals 0.53 (O / C ratio of initial lignocellulose biomass equals 0.98).

[0148] Example 3

[0149] Production of depolymerized lignocellulose biomass

[0150] 60 g of flaxseed oil cake (particle diameter < 2 mm) and 120 g of methanol [lignocellulosic biomass / methanol ratio (w / w) equal to 0.5] were placed in a 500 ml reactor. The mixture was kept at 250 °C and 90 bar for 120 minutes with stirring to obtain a gas phase (approximately 2.64 g) removed by vacuum and a mixture comprising a liquid phase and a solid phase, wherein the liquid phase comprises depolymerized lignocellulosic biomass and methanol, wherein the depolymerized lignocellulosic biomass comprises fatty acid methyl ester (FAME), and the solid phase comprises carbon residue (“char”), depolymerized lignocellulosic biomass, and undepolymerized lignocellulosic biomass.

[0151] The mixture was separated by filtration to obtain a solid phase (45 g) containing carbon residue (“char”), depolymerized lignocellulosic biomass and undepolymerized lignocellulosic biomass, and a liquid phase (150 g) containing depolymerized lignocellulosic biomass and methanol (the depolymerized lignocellulosic biomass contains fatty acid methyl ester (FAME)).

[0152] The solid phase was then purified and separated. For this purpose, the solid phase was placed in a 250 ml beaker equipped with a magnetic stirrer, and 100 g of pure methanol was added. The mixture was then kept at room temperature (25°C) for 15 minutes with stirring. Finally, the resulting mixture was separated by filtration twice to obtain a liquid phase (100 g) consisting of depolymerized lignocellulosic biomass and a solid phase containing carbon residues (“char”) and undepolymerized lignocellulosic biomass. This liquid phase was then combined with the liquid phase containing depolymerized lignocellulosic biomass, methanol, and fatty acid methyl ester (FAME). The solid phase was then dried in an oven at 85°C and 10 mbar for 10 hours to completely remove residual methanol; the final amount of dried solid corresponded to approximately 22 g.

[0153] A liquid phase containing depolymerized lignocellulosic biomass and methanol (the depolymerized lignocellulosic biomass containing fatty acid methyl ester (FAME)) (250 g) was evaporated for 30 minutes in a rotary evaporator operating at 650 mbar and 85°C to obtain depolymerized lignocellulosic biomass containing fatty acid methyl ester (FAME) (approximately 47.5 g - yield 56.2%) and methanol (202.5 g), the methanol of which can be recycled to the depolymerization step.

[0154] The molecular weight, H / C ratio, and H / O ratio of the depolymerized lignocellulose biomass containing fatty acid methyl esters (FAME) were determined as described above.

[0155] The results obtained are as follows:

[0156] - Weight-average molecular weight (M w The value is 790 Daltons;

[0157] - Number average molecular weight (M n The value is 90 Daltons.

[0158] - H / C ratio equals 0.13 (starting lignocellulosic biomass H / C ratio equals 0.14);

[0159] - H / O ratio equals 0.10 (initial lignocellulosic biomass H / O ratio equals 0.27);

[0160] - O / C ratio equals 1.34 (O / C ratio of initial lignocellulose biomass equals 0.52).

[0161] Example 4

[0162] Measurement of oxygen consumption

[0163] For this purpose, a commercial, antioxidant-free, food-grade sunflower seed oil was used, and the following comparative tests were conducted.

[0164] In a 10 ml flask, under magnetic stirring and at 35°C, add the following substances to sunflower seed oil:

[0165] - Commercial antioxidant 2,6-di-tert-butyl-p-cresol (BHT-Merck), which is 0.3% by weight relative to the total weight of sunflower seed oil (Sample B);

[0166] - The depolymerized lignocellulose biomass obtained in Example 2 had a concentration of 1% by weight relative to the total weight of sunflower seed oil (Sample A).

[0167] For comparison purposes, Figure 2 Sample C is also shown, consisting of commercial food-grade sunflower seed oil without antioxidants.

[0168] Next, after placing the flask in a silica bath and installing a condenser on top, insert a (pre-calibrated) oxygen-sensitive probe: keep the whole thing under magnetic stirring and raise the temperature to 130°C, then measure the oxygen consumption caused by the auto-oxidation of sunflower seed oil through the oxygen-sensitive probe.

[0169] exist Figure 2 [The horizontal axis represents time in seconds (s); the vertical axis represents the percentage (%) of oxygen (O2) present in the test atmosphere], which shows how adding the depolymerized lignocellulose biomass obtained in Example 2 increases the oxidation time of sunflower seed oil.

[0170] Example 5

[0171] Determination of antioxidant capacity

[0172] The depolymerized lignocellulose biomass obtained in Examples 2 and 3 was compared with the commercial antioxidant [2,6-di-tert-butyl-p-cresol (BHT-Merck)] using the Rancimat test according to EN 15751-2014: the test determined the oxidative stability of the depolymerized lignocellulose biomass by measuring an induction period of up to 48 hours.

[0173] Therefore, samples were prepared by mixing commercial food-grade soybean oil with the depolymerized lignocellulosic biomass obtained in Examples 2 and 3, such that the concentration of the depolymerized lignocellulosic biomass was 1% by weight relative to the total weight of the soybean oil (samples A and B). The samples thus prepared were inserted into a Rancimat device (Metrohm Herisau Switzerland).

[0174] Subsequently, purified air is passed through the sample, which has been preheated to 110°C. During oxidation, the volatile compounds formed are introduced along with the air into a flask containing demineralized water and a conductivity electrode: the conductivity electrode allows for the measurement of the end of the induction period, marked by a rapid increase in conductivity due to the dissociation of volatile carboxylic acids absorbed in the water.

[0175] For comparative purposes, the following samples were prepared by mixing commercial, antioxidant-free, food-grade soybean oil with the following substances:

[0176] - Commercial antioxidant 2,6-di-tert-butyl-p-cresol (BHT-Merck) was used, such that the concentration of 2,6-di-tert-butyl-p-cresol (BHT) was 0.3% by weight relative to the total weight of soybean oil (sample C).

[0177] - The depolymerized lignocellulose biomass obtained in Example 2 was such that the concentration of the depolymerized lignocellulose biomass was equal to 1% by weight relative to the total weight of soybean oil (Sample A).

[0178] - The depolymerized lignocellulose biomass obtained in Example 3 was such that the concentration of lignocellulose biomass relative to the total weight of soybean oil was 1% by weight (Sample B).

[0179] For comparison purposes, Figure 3 Sample D, consisting of commercial food-grade soybean oil, is also shown in the image.

[0180] The sample prepared as described above was placed in a Rancimat instrument (Metrohm Herisau Switzerland), and its antioxidant capacity was determined by the procedure described above. The results obtained are as follows: Figure 3 As shown.

[0181] according to Figure 3 The data shown [horizontal axis represents the sample; vertical axis represents the average induction time in hours (h)] suggests that the depolymerized lignocellulose biomass obtained in Examples 2 and 3, when accounting for 1% by weight of soybean oil, exhibits antioxidant activity comparable to that of the commercial antioxidant 2,6-di-tert-butyl-p-cresol (BHT-Merck) when accounting for 0.3% by weight of soybean oil.

Claims

1. A method for depolymerizing lignocellulose biomass, comprising the following steps: (a) In the presence of at least one alcohol having 1 to 5 carbon atoms, preferably 1 to 2 carbon atoms, under supercritical conditions, at a temperature of 200°C to 300°C, preferably 220°C to 295°C, at a pressure of 40 bar to 170 bar, preferably 50 bar to 150 bar, at a lignocellulose biomass / alcohol ratio of 0.1 to 1, preferably 0.15 to 0.8 wt / w, the lignocellulose biomass is depolymerized for 5 to 150 minutes, preferably 10 to 130 minutes, to obtain: - (i) A mixture comprising a liquid phase and a solid phase, the liquid phase comprising depolymerized lignocellulose biomass and at least one alcohol, the solid phase comprising carbon residue ("char"), depolymerized lignocellulose biomass and optionally undepolymerized lignocellulose biomass; - (ii) Optional gas phase; (b) Separating the liquid phase comprising depolymerized lignocellulose biomass and at least one alcohol from the mixture (i) obtained in step (a) to obtain: (iii) A liquid phase comprising depolymerized lignocellulose biomass and at least one alcohol; (iv) A solid phase comprising carbon residue ("char"), depolymerized lignocellulosic biomass, and optionally undepolymerized lignocellulosic biomass; (c) The liquid phase (iii) obtained in step (b) containing depolymerized lignocellulose biomass and at least one alcohol is purified to obtain: (v) Depolymerization of lignocellulose biomass; (vi) At least one alcohol.

2. The method for depolymerizing lignocellulose biomass according to claim 1, wherein the lignocellulose biomass is selected from: - Plants specifically cultivated for energy purposes, such as miscanthus, switchgrass (Panicum virgatum), and common reed (Arundo donax); - Plants not specifically cultivated for energy purposes, such as sorghum; - Waste, residues and waste products from agriculture, such as silver hyacinth, corn, soybeans, cotton, flax, rapeseed, wheat, rice, sugarcane and palm; - Waste, residues and waste products from forestry, afforestation or timber processing, such as fir, poplar, alder and birch; - Waste from agricultural food products intended for human consumption or livestock farming; - Untreated residues from the paper industry; - Waste collected from the municipal solid waste sorting system; - Algae, such as microalgae or macroalgae, especially macroalgae.

3. The method for depolymerizing lignocellulosic biomass according to claim 1, wherein the lignocellulosic biomass is selected from waste (oil cake) derived from extruded plant seeds ("oilseed cake" or "oilseed extrusion cake"), such as flax, rapeseed, soybean, sunflower, rapeseed, safflower, flax, rubber tree, castor bean, cotton, and sea cabbage.

4. The method for depolymerizing lignocellulosic biomass according to any one of the preceding claims, wherein prior to the depolymerization step (a), the lignocellulosic biomass is subjected to a preliminary grinding process, preferably grinding the lignocellulosic biomass until particles with a diameter of 0.05 mm to 2.5 mm, more preferably 0.08 mm to 2 mm, and even more preferably particles with a diameter of less than 2 mm are obtained.

5. The method for depolymerizing lignocellulosic biomass according to any one of the preceding claims, wherein in the depolymerization step (a), the at least one alcohol is selected from methanol, ethanol, propanol, butanol, pentanol or a mixture thereof; preferably selected from methanol, ethanol or a mixture thereof.

6. The method for depolymerizing lignocellulose biomass according to any one of the preceding claims, wherein the separation step (b) is carried out by filtration, decantation, or centrifugation, preferably by filtration.

7. A method for depolymerizing lignocellulosic biomass according to any one of the preceding claims, wherein a solid phase (iv) comprising carbon residue ("char"), depolymerized lignocellulosic biomass, and optionally undepolymerized lignocellulosic biomass is subjected to a purification and separation step (d) to obtain: (vii) Liquid phase composed of undepolymerized lignocellulose biomass; (viii) A solid phase comprising carbon residues ("char") and optional undepolymerized lignocellulosic biomass.

8. The method for depolymerizing lignocellulosic biomass according to claim 7, wherein in step (d), the purification is carried out by washing with at least one alcohol, preferably the at least one alcohol used in the depolymerization step (a), and more preferably with methanol, ethanol, or a mixture thereof.

9. The method for depolymerizing lignocellulose biomass according to claim 7 or 8, wherein in step (d), the separation is carried out by filtration, decantation, or centrifugation, preferably by filtration.

10. A method for depolymerizing lignocellulose biomass according to any one of the preceding claims, wherein the purification step (c) is carried out by vacuum distillation.

11. Depolymerized lignocellulose biomass that does not contain fatty acid esters, and has the following characteristics: - Weight-average molecular weight (M w Less than or equal to 1200 Daltons, preferably 150 Daltons to 1000 Daltons, and even more preferably 200 Daltons to 900 Daltons; - Number average molecular weight (M n Less than or equal to 500 Daltons, preferably 80 to 400 Daltons, more preferably 100 to 300 Daltons; - The percentage change of the H / C ratio of depolymerized lignocellulosic biomass relative to the H / C ratio of the starting lignocellulosic biomass is equal to an increase of at least 30%, preferably 35% to 250%, and even more preferably 50% to 230%. - The percentage change of the H / O ratio of depolymerized lignocellulosic biomass relative to the H / O ratio of the starting lignocellulosic biomass is equal to an increase of at least 40%, preferably 45% to 500%, and even more preferably 60% to 450%. - The percentage change in the O / C ratio of depolymerized lignocellulosic biomass relative to the O / C ratio of the starting lignocellulosic biomass is equal to at least a 20% reduction, preferably a 25% to a 250% reduction, and even more preferably a 30% to a 200% reduction.

12. Depolymerized lignocellulosic biomass containing fatty acid esters, which has the following characteristics: - Weight-average molecular weight (M w Less than or equal to 1200 Daltons, preferably 150 Daltons to 1000 Daltons, and even more preferably 200 Daltons to 900 Daltons; - Number average molecular weight (M n Less than or equal to 400 Daltons, preferably 50 to 390 Daltons, more preferably 60 to 350 Daltons; - The percentage change in the H / C ratio of depolymerized lignocellulosic biomass relative to the H / C ratio of the starting lignocellulosic biomass is equal to at least a 2% reduction, preferably a 4% reduction to a 200% reduction, or even more preferably a 6% reduction to a 180% reduction. - The percentage change of the H / O ratio of depolymerized lignocellulosic biomass relative to the H / O ratio of the starting lignocellulosic biomass is equal to at least a 5% reduction, preferably a 10% reduction to a 200% reduction, or even more preferably a 20% reduction to a 150% reduction. - The percentage change in the O / C ratio of depolymerized lignocellulosic biomass relative to the O / C ratio of the starting lignocellulosic biomass is equal to an increase of at least 30%, preferably 35% to 350%, and even more preferably 40% to 280%.

13. The use of depolymerized lignocellulosic biomass as an antioxidant or UV stabilizer, preferably as an antioxidant or UV stabilizer in biofuels, which can be used as is or mixed with other fuels in automobile or aviation diesel engines.

14. Use of depolymerized lignocellulose biomass as an antioxidant in bio-raw materials such as vegetable oils and animal or plant fats.

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