WO2017095316A1

WO2017095316A1 - Depolymerized lignin in hydrocarbon oil

Info

Publication number: WO2017095316A1
Application number: PCT/SE2016/051199
Authority: WO
Inventors: Alexander OREBOM; Joseph Samec; Johan VERENDEL
Original assignee: Ren Fuel K2B Ab
Priority date: 2015-12-01
Filing date: 2016-12-01
Publication date: 2017-06-08
Also published as: SE1551569A1; SE542463C2

Abstract

The present invention relates to a composition comprising depolymerized lignin derivatives and a solvent and wherein the composition is suitable for preparing fuel. The depolymerized lignin comprises phenol derivatives and the composition has a very low metal content.

Description

DEPOLYMERIZED LIGNIN IN HYDROCARBON OIL

FIELD OF THE INVENTION

The present invention relates to a composition of lignin derivative and a solvent such as a hydrocarbon oil, fatty acid or the like. The composition may be used as an additive to fuels but it is also suitable for refinery process for preparing fuels.

BACKGROUND

There is an increasing interest in using biomass as a source for fuel production. Biomass includes, but is not limited to, plant parts, fruits, vegetables, processing waste, wood chips, chaff, grain, grasses, corn, corn husks, weeds, aquatic plants, hay, paper, paper products, recycled paper and paper products, lignocellulosic material, lignin and any cellulose containing biological material or material of biological origin.

An important component of biomass is the lignin present in the solid portions of the biomass. Lignin comprises chains of aromatic and oxygenate constituents forming larger molecules that are not easily depolymerized or modified. A major reason for difficulty in depolymerize the lignin is the inability to disperse the lignin for contact with catalysts that can break the lignin down.

Lignin is one of the most abundant natural polymers on earth. One common way of preparing lignin is by separation from wood during pulping processes. Only a small amount (1-2 %) is utilized in specialty products whereas the rest primary serves as fuel. Even if burning lignin is a valuable way to reduce usage of fossil fuel, lignin has significant potential as raw material for the sustainable production of chemicals and liquid fuels. Various lignins differ structurally depending on raw material source and

subsequent processing, but one common feature is a backbone consisting of various substituted phenyl propane units that are bound to each other via aryl ether or carbon-carbon linkages. They are typically substituted with methoxy groups and the phenolic and aliphatic hydroxyl groups provide sites for further functionalization. Lignin is known to have a low ability to sorb water compared to for example the hydrophilic cellulose. Today lignin may be used as a component in for example pellet fuel as a binder but it may also be used as an energy source due to its high energy content. Lignin has higher energy content than cellulose or hemicelluloses. The heating value for lignin is on average 22.7 kJ/g , which is 30% more than the energy content of cellulosic carbohydrate and similar to that of coal. In a pulp or paper mill, lignin that has been removed using the kraft- or sulphate process is usually burned in order to provide energy to run the production process and to recover the chemicals from the cooking liquor.

There are several ways of extracting the lignin from black or red liquor obtained after separating the cellulose fibres in the kraft or sulphite process respectively.

One of the most common strategies is membrane or ultra-filtration. Lignoboost®, a separation process developed by Innventia AB, has been shown to increase the lignin yield using sulphuric acid. In the Lignoboost® process, black liquor from the production processes is taken and the lignin is precipitated through the addition and reaction with acid, usually from carbon dioxide (CO2) . The lignin is then filtered off and the filter cake re-dispersed and acidified, usually using sulphuric acid. The obtained slurry is then filtered and washed using displacement washing. The lignin is usually then dried and pulverized in order to make it suitable for lime kiln burners or before pelletizing it into pellet fuel. Biofuel, such as biogasoline and biodiesel, is a fuel in which the energy is mainly derived from biomass material such as wood, corn, sugarcane, animal fat, vegetable oils and so on. However the biofuel industries are struggling with issues like food vs fuel debate, efficiency and the general supply of raw material. At the same time the pulp or paper making industries produces huge amounts of lignin which is often, as described above, only burned in the mill. Two common strategies for exploring biomass such as lignin as a fuel or fuel component are to use pyrolysis oils or hydrogenated lignin.

In order to make lignin more useful in further transformations one has to solve the problem with the low solubility of lignin in organic solvents. One challenge of using lignin as a source for fuel production is the issue of providing lignin in a form suitable for hydrotreaters or crackers. The problem is that lignin is insoluble in oils or fatty acids which is, if not necessary, highly wanted. Prior art provides various strategies for degrading lignin into small units or molecules in order to prepare lignin derivatives that may be processed. These strategies include hydrogenation, dexoygenation and acid catalyst hydrolysis.

WO2011003029 relates to a method for catalytic cleavage of carbon-carbon bonds and carbon-oxygen bonds in lignin. US20130025191 relates to a depolymerisation and deoxygenation method where lignin is treated with hydrogen together with a catalyst in an aromatic containing solvent. All these strategies relates to methods where the degradation is performed prior to eventual mixing with fatty acids or oils. WO2008/ 157164 discloses an alternative strategy where a first dispersion agent is used to form a biomass suspension to obtain a better contact with the catalyst.

These strategies usually also requires isolation of the degradation products in order to separate them from unwanted reagents such as solvents or catalysts.

In WO2015/ 094099 the present applicant presents a strategy where lignin is modified with an alkyl group via an ester linkage in order to make the lignin more soluble in oils or fatty acids. In WO2014/ 116173 the present applicant teaches a composition of lignin or lignin derivatives in a carrier liquid and a solvent where the lignin has a molecular weight of not more than 5,000g/mol.

WO2014/ 193289 teaches a method where black liquor is membrane filtrated followed by a depolymerization step where after the depolymerized lignin is separated. The depolymerization may be done by treating the membrane filtrated lignin at high temperature and pressure.

The economic benefits of producing fuels from biomass depend for example on an efficient process for preparing the lignin and on the preparation of the lignin or lignin derivatives so that the fuel production is as efficient as possible. For example the amount of oxygen should be as low as possible and the number of preparation steps should be as few as possible. High oxygen content requires more hydrogen during the refinery process.

One way of making fuel production from lignin more beneficial would be if lignin may be processed using common oil refinery techniques such catalytic cracking or hydrotreatment. In order to do that the lignin needs to be soluble in refinery media such as hydrocarbon oils. SUMMARY OF THE INVENTION

The object of the present invention is to overcome the drawbacks of the prior art and provide a composition comprising lignin derivative and a solvent. The lignin material is not only depolymerized it is also deoxygenated fully or partially, i.e. the oxygen content is reduced. One application for the composition may be as a raw material for fuel production or as an additive to fuel or oil.

In a first aspect the present invention relates to a composition comprising lignin derivative and a solvent liquid wherein the lignin derivative has a weight average molecular weight of 250-650g/mol. In a second aspect the present invention relates to a method of preparing the composition according to the present invention comprising

-adding an alkali aqueous lignin solution to a container;

-sealing the container;

-heating the black or red liquor to at least 270° C to depolymerize the lignin to a weight average molecular weight of 250-650g/mol; and

-mixing the depolymerized lignin with a solvent.

In a third aspect the present invention relates to a method of preparing fuel comprising treating the composition according to the present invention in a hydrotreater or a catalytic cracker. In a fourth aspect the present invention relates to a fuel obtained from the composition according to the present invention.

In a fifth aspect the present invention relates to a fuel additive comprising the composition according to the present invention.

In a sixth aspect the present invention relates to a fuel comprising the composition according to the present invention.

In a seventh aspect the present composition may be used as a concreted grinding aid, set retarder for cement, strengthener of cement, antioxidant, enhancer of thermal protection, stabilizer in asphalt, emulsifying agent, fiber strengthening additive, cross-linking agent, board binder, anti-corrosion additive, wear resistant additive, antifriction additive, binder, emulsifier or dispersing agent, cross-linking or curing agent, or as a water absorption inhibitor or as a fluidization agent, as an anti-bacterial or anti-fungal surface or as a barrier, to impregnate wood or as an anti-corrosion agent.

In an eight aspect the present invention may be used for producing tyres or paint.

In a ninth aspect the present invention relates to a method of depolymerizing lignin comprising

-adding an alkali aqueous lignin solution to a container; -sealing the container; and

-heating the alkali aqueous lignin solution to at least 270°C to depolymerize the lignin to a weight average molecular weight of 250-650g/mol.

In a tenth aspect the present invention relates to a composition comprising depolymerized Kraft lignin derivatives and a solvent wherein at least 2.5 weight% of the depolymerized lignin derivatives are phenol derivatives.

In an eleventh aspect the present method may be used to produce phenol derivatives wherein the phenol derivatives are separated from the alkali lignin solution using any suitable technique.

BRIEF DESCRIPTION OF FIGURES

Figure 1 , schematic view of lignin.

Figure 2, table over yield and coke formation from the method according to the present invention.

Figure 3, char formation from the present invention and the effect of alcohol addition to the method. Reaction temperature is 410 °C.

Figure 4, graph disclosing the effect of lignin concentration and char formation.

Figure 5, schematic description of the described process, including separation of the components such as organic phase, aqueous phase and char. Figure 6, graph disclosing the effect of temperature and yield.

Figure 7, graph disclosing the effect of temperature and char yield.

Figure 8, graph disclosing the effect of temperature and LGO-solubility of the depolymerized lignin. Figure 9, graph disclosing the effect of time and yields of ethyl acetate- and LGO- soluble materials.

Figure 10, graph disclosing the effect of time and char yield.

Figure 1 1 , graph disclosing the effect of oxygen concentration and and yields of ethyl acetate- and LGO- soluble materials. Figure 12, graph disclosing the effect of oxygen concentration and char yield.

Figure 13, graph disclosing the effect of reactor filling volume and yields of ethyl acetate- and LGO- soluble materials.

Figure 14, graph disclosing the effect of reactor filling volume and char yield.

Figure 15, graph disclosing the effect of black liquor age, yield of ethyl acetate soluble material and char.

Figure 16, Ή NMR spectra of kraft lignin (red) and of bio oil (blue) (ethyl acetate extracted product).

Figure 17, HSQC spectra of kraft lignin (red) and of bio oil (blue) (ethyl acetate extracted product). Figure 18, HMBC spectra of kraft lignin (red) and of bio oil (blue) (ethyl acetate extracted product).

Figure 19, a size exclusion chromatogram comparing sizes of acid precipitated lignin (2274 Da) and bio oil (473 Da) obtained after 1 hour at 400 °C.

Figure 20, GC-MS spectra of bio oil. Figure 21, a graph disclosing simulated distillation of bio oil. Figure 22, MALDI-TOF-MS spectra of bio oil at different concentrations. Figure 23, PNMR of the depolymerized lignin derivatives.

Figure 24, GC-MS chromatogram of ethyl acetate extracted sample obtained at 380 °C (top) and reference phenols (bottom).

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a composition for use in a refinery processes for the production of various fuels or chemicals.

In the present application the term "lignin" means a polymer comprising coumaryl alcohol, coniferyl alcohol and sinapyl alcohol monomers. Figure 1 discloses a schematic picture of native lignin.

In the present application the term "lignin derivative" means molecules or polymers derived from lignin.

In the present application the term "carrier liquid" means an inert hydrocarbon liquid suitable for a hydrotreater or a catalytic cracker (cat cracker) a liquid and may be selected from fatty acids or mixture of fatty acids, esterified fatty acids, triglyceride, rosin acid, crude oil, mineral oil, tall oil, creosote oil, tar oil, bunker fuel and hydrocarbon oils or mixtures thereof.

In the present invention the term "oil" means a nonpolar chemical substance that is a. viscous liquid at ambient temperature and. is both hydrophobic and lipophilic.

In the present application the terms "red liquor" and "brown liquor" denote the same liquor.

In the present invention solubility of the depolymerized lignin derivatives is determined by dissolution of a known amount of a substance in a known amount of solvent, followed by filtration by means of a centrifuge to determine the amount of dissolved substance. This is also disclosed in Example 1.

In the present invention the wording "fresh aqueous alkali lignin solution" means an aqueous alkali solution that is taken from the pulping process the same day. The solution is preferably so fresh that it is still heated, i.e. it may have a temperature close to the temperature it has when the solution leaves the boiler. Aged black liquor has shown to lower the yield of the bio oil and increase the yield of char, Figure 15. For a substance to be processed in a refinery such as an oil refinery or bio oil refinery, the substance needs to be in liquid phase. Either the substance is in liquid phase at a given temperature (usually below 80 °C) or the substance is solvated in a liquid. In this patent application, such liquid will be given the term solvent or carrier liquid. The present invention presents a composition and a method of preparing said composition where the composition comprises lignin, where the composition is in liquid phase and may be processed in a refinery such as an oil refinery. The present invention makes it easier or even facilitates production of fuel from lignin through conventional oil refinery processes.

Lignin In order to obtain lignin, biomass may be treated in any suitable way known to a person skilled in the art. The biomass may be treated with pulping processes or organosolv processes for example. Biomass includes, but is not limited to wood, fruits, vegetables, processing waste, chaff, grain, grasses, corn, corn husks, weeds, aquatic plants, hay, paper, paper products, recycled paper, shell, brown coal, algae, straw, bark or nut shells, lignocellulosic material, lignin and any cellulose containing biological material or material of biological origin. In one embodiment the biomass is wood, preferably particulate wood such as saw dust or wood chips. The wood may be any kind of wood, hard or soft wood, coniferous tree or broad-leaf tree. A non-limiting list of woods would be pine, birch, spruce, maple, ash, mountain ash, redwood, alder, elm, oak, larch, yew, chestnut, olive, cypress, banyan, sycamore, cherry, apple, pear, hawthorn, magnolia, sequoia, walnut, karri, coolabah and beech.

It is preferred that the biomass contains as much lignin as possible. The Kappa number estimates the amount of chemicals required during bleaching of wood pulp in order to obtain a pulp with a given degree of whiteness. Since the amount of bleach needed is related to the lignin content of the pulp, the Kappa number can be used to monitor the effectiveness of the lignin- extraction phase of the pulping process. It is approximately proportional to the residual lignin content of the pulp.

K * c*l

K: Kappa number; c: constant « 6.57 (dependent on process and wood); 1: lignin content in percent. The Kappa number is determined by ISO 302:2004. The kappa number may be 20 or higher, or 40 or higher, or 60 or higher. In one embodiment the kappa number is 10- 100.

The biomass material may be a mixture of biomass materials and in one

embodiment the biomass material is black or red liquor, or materials obtained from black or red liquor. Black and red liquor contains cellulose, hemi cellulose and lignin and derivatives thereof. The composition according to the present invention may comprise black or red liquor, or lignin obtained from black or red liquor.

The alkali aqueous lignin solution may be membrane filtrated prior to

depolymerization. The membrane filtration may be performed using one or more membranes with different cut offs. Depending on the cut off of the membrane the permeate or the retentate is collected and depolymerized. In one embodiment no filtration is done prior to the depolymerization.

The alkali aqueous lignin solution may be solution obtained from a pulp mill for example black or red liquor. Black liquor comprises four main groups of organic substances, around 30-45 weight% ligneous material, 25-35 weight% saccharine acids, about 10 weight% formic and acetic acid, 3-5 weight% extractives, about 1 weight% methanol, and many inorganic elements and sulphur. The exact composition of the liquor varies and depends on the cooking conditions in the production process and the feedstock. Red liquor comprises the ions from the sulfite process (calcium, sodium, magnesium or ammonium), sulfonated lignin, hemicellulose and low molecular resins. The pH of black liquor is usually around 13 such as 12-14. In one embodiment the black liquor is obtained from a pulping process of broadleaf wood, coniferous wood or a mixture of broadleaf and coniferous wood. In order to determine that the depolymerized lignin compounds or derivatives are derived from lignin any suitable C14 methods may be used. The age of the depolymerized lignin may be less than 75 years, or less than 50 years, or less than 30 years.

Lignin derivative

The lignin derivative according to the present invention is a depolymerized lignin preferably having a weight average molecular weight (M_w) of 150-850g/mol such as 250-650g/mol. In one embodiment the molecular weight is 270g/mol or higher, or 300g/mol or higher, or 330g/mol or higher, or 360g/mol or higher, or 600g/mol or less, or 550g/mol or less, or 500g/mol or less, or 480g/mol or less, or 450g/mol or less, or 400g/mol or less, or 380g/mol or less. The polydispersity is preferably lower than 5, preferably lower than 3, even more preferably lower than 2. In one embodiment at least 65% of the depolymerized lignin derivatives may be distilled below 700°C. In another embodiment at least 50% may be distilled below 500°C. In yet another embodiment at least 20% may be distilled below 300°C.

Molecular weight (M_w) in the present application is determined using GPC (Gel Permeation Chromatography) operated at 20°C and at flow rate of 1 ml/min using THF as solvent. Polystyrene Standard RedayCal Set M(p) 250-70000 (16 standards) (Sigma product no: 76552). The columns are Styragel THF (pre-column), Styragel HR 3 THF (7.8x300 mm), Styragel HR 1 THF (7.8x300 mm), Styragel HR 0.5 THF (7.8x300 mm) all from Waters. The lignin derivative according to the present invention has a low oxygen content such as 1 1% or less, or 9% or less, or 8% or less, or 7% or less, or 6% or less, or 5% or less. The lignin derivative may have the following element content: carbon 70- 90%, such as 75-85%, or 80-83%, hydrogen 5- 12%, such as 6-9%, nitrogen 0-0.5% such as 0.1-0.2%, oxygen 3-10% such as 4-8% or 5-7%, sulfur 0- 1% such as 0.4- 0.8%. Since metal residues from the cooking chemicals are not wanted in the refinery process the metal content should be as low as possible. The lignin derivative according to the present invention may have a calcium content of 0- 70ppm such as 40ppm or less for example 10-30ppm, iron 0-50ppm such as 30ppm or less for example 10-20ppm, potassium 0-50ppm such as 30ppm or less for example 10-20ppm, magnesium 0-300ppm such as 200ppm or less for example 50- 150ppm, sodium 0-600ppm such as 500ppm or less for example 100-400ppm or 200-300ppm. In one embodiment the total metal content is less than lOOppm, such as less than 80ppm, or less than 60ppm. The amount of chlorine may also be very low since no added catalyst or additives are present during the

depolymerization. The ICP analysis (elemental analysis) is done by extraction using ethyl acetate and wherein the ethyl acetate is removed by evaporation leaving dried lignin derivative. An advantage of the present invention is that the lignin in the composition does not have to be hydrotreated during the depolymerization step or in an additional step in order to become soluble in a carrier liquid.

The depolymerized lignin derivatives are mainly a mixture of aromatic compounds having alkyl groups such as phenol derivatives. The ratio between the phenol derivatives and the alkyls may be 1 : 10 to 1: 1 such as 1:6 to 1 :2 or around 1:3 to l:4.This ratio may be determined using H-NMR.

The depolymerized lignin comprises phenol derivatives, Figure 24. The phenol derivatives are low molecular weight compounds which are petrol or diesel like and usually have a molecular weight of 160g/mol or less, or 150g/mol or less, or 140g/mol or less but preferably 108g/mol or higher. In one embodiment the molecular weight of the phenols is in the range of 108 to 150g/mol. In one embodiment the phenol derivatives contains one aromatic ring, one hydroxyl group and not more than three alkyl groups selected from C1-C3 alkyls. The phenol derivatives are mainly methylated, ethylated or propylated phenols such as 4- methyl phenol, 2,3,5-trimethyl phenol, 3,5-dimethyl phenol, 2,6-dimethyl phenol, 2,4-dimethyl phenol, 2,5-dimethyl phenol, 2,4,6-trimethyl phenol 3,4,5-trimethyl phenol, 2-ethyl-5-methyl phenol, 2-ethyl-4-methyl phenol and 2,3-dimethyl phenol. The depolymerized lignin also contains methylated cyclopenen-2-one. The amount of phenol derivatives of the depolymerized lignin derivatives may be at least 2.5weight%, or at least 3 weight%, or at least 3.5weight%, or at least 4weight%, or at least 4.5weight%, or at least 5weight%, or at least 5.5weight%, or at least

8weight%, or at least 10weight%, or at least 12 weigh t%, or at least 15weight%, or at least 20weight%. In one embodiment the amount of phenol derivatives is 3- 25weight%, or 3.5- 15weight%, or 4 to 10 weigh t%, or 5-7weight%. Phenol derivatives and amount of phenol derivatives are determined using GC-MS and phenol standards (weight of phenols / weight of sample) .

One advantage of the present invention is that the amount of anisoles is

significantly reduced. Anisoles are unwanted in a refinery since they increase the hydrogen consumption. The composition may be essentially free from anisoles. The amount of anisoles of the depolymerized lignin in the composition may be less than 0.5wt%, preferably less than 0.1wt%, preferably less than 0.01wt%.

Solvent

According to the present invention the composition comprises a solvent for example a carrier liquid or an organic solvent or a mixture of a carrier liquid and an organic solvent. The carrier liquid may be an oil may be any suitable oil for example a hydrocarbon oil, crude oil, bunker oil, mineral oil, tall oil, creosote oil, tar oil, fatty acid or esterified fatty acid. In one embodiment the carrier liquid is a fatty acid or a mixture of fatty acids. The fatty acid may be a tall oil fatty acid (TOFA) or refined or distilled TOFA. In another embodiment the carrier liquid is esterified fatty acids such as FAME (fatty acid methyl ester) or triglyceride. In one embodiment the carrier liquid is a crude oil. In one embodiment the carrier liquid is bunker fuel or bunker crude. In another embodiment the carrier liquid is a hydrocarbon oil or a mineral oil. In one embodiment the carrier liquid is a mixture of esterified fatty acid and a mineral oil, hydrocarbon oil, bunker fuels or crude oil. In another

embodiment the carrier liquid is a mixture of a hydrocarbon oil or a mineral oil and a fatty acid. In one embodiment the carrier liquid is creosote oil or tar oil. Since the composition may be used for preparing fuels the carrier liquid does not have to be an already hydrotreated or cracked liquid such as diesel, instead the carrier liquid should be a liquid that may be hydrotreated or cracked in a refinery process in order to form fuel. By using a non-hydrotreated or non-cracked carrier liquid conventional refinery processes may be used and carrier liquids that any way would be refined can be used.

The carrier liquid should preferably be suitable for a hydrotreater or a catalytic cracker (cat cracker), preferably a liquid suitable for both hydrotreater and catalytic cracker. Hydrotreating and catalytic cracking are common steps in the oil refinery process where the sulfur, oxygen and nitrogen contents of the oil is reduced and where high-boiling, high molecular weight hydrocarbons are converted into gasoline, diesel and gases. The esterified fatty acid may be any suitable fatty acid esterified with any suitable group. The fatty acid used in the present invention (as fatty acid or as esterified fatty acid) may be a C8 or longer fatty acid, or a CI 4 or longer fatty acid. In another embodiment the fatty acid or the mixture of the fatty acids comprises unsaturated fatty acids, preferably at a concentration of more than 25 wt%, or more than 50 wt%. In one embodiment the carrier liquid is a tall oil or crude tall oil (CTO). When the carrier liquid is a mixture of an oil (hydrocarbon oil, mineral oil, crude oil or bunker fuel) and a fatty acid or esterified fatty acid the ratio in said mixture may be in the range 1-99 wt% fatty acid (or esterified fatty acid) and 1-99 wt% of the oil, for example 20-40 wt% fatty acid (or esterified fatty acid) and 60-80 wt% of the oil (hydrocarbon oil, mineral oil, crude oil or bunker fuel). In one embodiment the carrier liquid comprises 1-15 wt% esterified fatty acid, such as 2- 10 wt% or 3-6 wt%. When the carrier liquid is or comprises a hydrocarbon oil the oil needs to be in liquid phase below 80 °C and preferably have boiling points of 177-371 °C. These hydrocarbon oils include different types of or gas oils and likewise e.g. light cycle oil (LCO), Full Range Straight Run Middle Distillates, Hydrotreated, Middle Distillate, Light Catalytic Cracked Distillate, distillates Naphtha full-range straight-run, hydrodesulfurized full-range, solvent-dewaxed straight-range, straight-run middle sulfenylated, Naphtha ckty-treated full-range straight run, distillates full-range aim, distillates hydrotreated full-range, straight-run light, distillates heav straight-run, distillates (oil sand), straight-run middle-run. Naphtha (shale oil), hydrocracked, full-range straight run (example of but not restricted to CAS nr: 68476-30-2, 68814-87-9, 74742-46-7, 64741-59-9, 64741-44-2, 64741-42-0, 101316-57-8, 101316-58-9, 91722-55-3, 91995-58-3, 68527-21-9, 128683-26- 1 , 91995-46-9, 68410-05-9, 68915-96-8, 128683-27-2, 195459- 19-9). In one embodiment the hydrocarbon oil is a gas oil such as light gas oil (LGO).

Bunker fuel or bunker crude are fuel mainly used for ships, usually very large ships. The bunker fuel may be divided into groups depending on if the fuel is a distillate or a residual or a mixture of both and the chain length. For example No. 1 fuel oil is a distillate with a chain length of 9-16, No. 2 fuel oil (also known as Bunker A) is a distillate with a chain length of 10-20, No. 4 and No. 5 fuel oil (also known as Bunker B) is a distillate and a residual oil respectively with a chain length of 12-70 and No. 6 fuel oil (also known as Bunker C) is a residual (heavy fuel oil) with a chain length of 20-70. No. 5 and 6 are also known as heavy fuel oil (HFO) or furnace fuel oil (FFO). In one embodiment the bunker fuel is a Bunker B. In another embodiment the bunker fuel is a HFO or Bunker C. By adding lignin derivative to the bunker fuel the fuel becomes more environmentally friendly. The composition may comprise 10-99 weight% of carrier liquid of the total weight of the composition, such as 20 weight% or more, or 40 weight% or more, or 60 weight% or more, or 80 weight% or more, or 99 weight% or less, or 85 weight% or less, or 65 weight% or less. In one embodiment the amount of carrier liquid is 60- 90 weight% such as 65-85 weight%.

The solvent may also be an organic solvent or a mixture of organic solvents. In one embodiment the solvent is a mixture of an organic solvent and a carrier liquid. The organic solvent may be but is not limited to oxygenates such as an alcohol, ester, ketone, ether, aldehydes, furan or furfural based solvent. Preferred solvents are Cl- CIO alcohols, C1-C10 aldehydes, C2-C15 ketones, C2-C10 ethers, and C2-C10 esters. A non-limiting list of solvents is methanol, ethanol, propanol, isopropanol, glycerol, and butyl ether such as tert-butyl methyl ether; diethyl ether, diglyme, diisopropyl ether, dimethoxyethane, diethylene glycol, diethyl ether, polyethylene glycol, 1,4-dioxane and tetrahydrofuran, methylated tetrahydrofuran, mesityl oxide, furfural, isophorone. Preferred C2-C10 esters are organic esters, aromatic or non- aromatic esters, examples of esters are benzyl benzoate, various acetates such as methyl acetate, ethyl acetate, cyclopentyl methyl ether and butyl acetate, various lactates such as ethyl lactates. Solvents that are similar to or may be converted into fuel or petrol are interesting when the composition is to be used for fuel

preparation. Such solvents could be ketones or aldehydes. In one embodiment the solvent is a C2-C15 ketone such as a C4-C12 ketone or a C6-C8 ketone. In one embodiment the solvent is a C1-C10 aldehyde such as a C4-C9 aldehyde or C6-C8 aldehyde. In one embodiment the solvent is a mixture of a C2-C15 ketone and a Cl- C10 aldehyde. In one embodiment the solvent is mesityl oxide. In one embodiment the solvent is acetone. In one embodiment the solvent is acetophenone. In one embodiment the solvent is pentanone. In one embodiment the solvent is ethyl isopropyl ketone. In one embodiment the solvent is isophorone. In one embodiment the organic solvent is an aromatic aldehyde or a mixture containing an aromatic aldehyde for example furfural. In one embodiment the solvent comprises furfural or furfuryl alcohol. In one embodiment the solvent is benzaldehyde. In one

embodiment the solvent is ethyl acetate. In one embodiment the solvent is a CI -CIO alcohol. In one embodiment the solvent is ethanol. In one embodiment the solvent is methanol. In one embodiment the solvent is isopropanol. In one embodiment the solvent is solketal. In one embodiment the solvent is a C2-C10 ester. In one embodiment the solvent is tetrahydrofuran or methylated tetrahydrofuran. In one embodiment the solvent is 1,4-dioxane.

In one embodiment the solvent comprises a combination of C1-C10 alcohols, C2- C10 ethers and C2-C10 esters. In one embodiment the solvent comprises two Cl- CIO alcohols for example ethanol and glycerol, and in another embodiment the solvent comprises propanol and glycerol. In one embodiment the solvent comprises polyethylene glycol and a C1-C10 alcohol. When the solvent is a mixture of an organic solvent and water the mixture may contain methanol and water, ethanol and water, isopropanol and water or ethyl acetate and water, preferably ethanol and water, isopropanol and water and ethyl acetate and water.

In one embodiment the solvent is a mixture of a C2-C15 ketone such as a C4-C12 ketone or a C6-C8 ketone or a C1-C10 aldehyde such as a C4-C9 aldehyde or C6- C8 aldehyde and a carrier liquid. In one embodiment the solvent is a mixture of a C1-C10 alcohol such as a C3-C8 alcohol and a carrier liquid. In one embodiment the amount of added organic solvent in the composition is 1-99 weight% of the total weight of the composition. In one embodiment the amount of solvent is 1-60 weight%, or 5-50 weight%, or 10-30 weight%. In one embodiment the amount of organic solvent is 70 weight% or less, or 40 weight% or less, or 20 weight% or less, or 10 weight% or less, or 5 weight% or less, or 2 weight% or less, or 1 weight% or less of the total weight of the composition. In one embodiment the composition comprises 0.1- lwt% of ethanol, for example 0.2 to 0.5wt%. In one embodiment the composition is essentially free from any added organic solvents. Organic solvents and water may have a negative effect when the composition is treated in a refinery for example it may harm the catalysts or the products may be oxidated and therefore the concentration of organic solvent or water should in some applications be kept as low as possible.

The composition generally comprises depolymerized lignin and the solvent however it may contain other compounds as well. However one of the advantages of the present invention is that a composition comprising essentially only a solvent and depolymerized lignin may be prepared. In one embodiment at least 95wt% of the composition comprises depolymerized lignin and solvent, such as at least 98wt%, or at least 99wt%, or at least 99.5wt%. Preparation of the composition

The present inventors found that by depolymerizing the lignin to small polymeric or oligomeric fractions the solubility of the lignin increased drastically in more non- polar solvents and even in lipophilic solvents such as oils. A general and schematic disclosure of the method according to the present invention is disclosed in figure 5. Any necessary pumps are not shown. The present method may be done in batch mode or in a continuous mode using for example a flow reactor or several reactors. An aqueous alkali lignin solution such as black liquor is added to a reactor and depolymerized by heating the solution under pressure. The reactor is vented to release gas and the depolymerized lignin is isolated for example by adding an extraction solvent which extracts the

depolymerized lignin through liquid-liquid extraction (extracted part). The remaining aqueous solution and solid may be filtrated to separate the aqueous solution from the char or coke. The composition according to the present invention may be prepared by first preparing the lignin derivative followed by mixing said modified lignin with the solvent. The lignin derivative may be isolated from the depolymerization reaction mixture or the lignin derivative may be left in the reaction mixture when mixed with the carrier liquid. The depolymerization of the lignin may also be performed in the presence of the carrier liquid. The mixing can be done by stirring or shaking or in any other suitable way and the slurry is then heated. Any catalyst and any other unwanted components may be removed afterwards using any suitable technique.

The depolymerization of the lignin is preferably a thermal depolymerization process where temperature and pressure facilitates the depolymerization of the lignin. No added catalyst, such as transition metal catalysts, is necessary. Without being bound be theory but the cooking chemicals, the salts or the base, present in the black or red liquor, are believed to be important. Studies performed by the present inventors have shown no or very low depolymerization when the thermal treatment is performed in pure water. The depolymerization may be performed at 270°C or higher, or 300°C or higher, or 310°C or higher, or 320°C or higher, or 330°C or higher, or 340°C or higher, or 350°C or higher, but preferably not higher than 500°C, or 450°C or lower, or 420°C or lower, or 400°C or lower, or 390°C or lower, or 380°C or lower, or 370°C or lower, or 360°C or lower. The thermal treatment time depends on the volume of the liquor to be treated, as an example a sample of 5-6g of black liquor is treated for at least 20 minutes. In one embodiment the

temperature is 370°C-420°C or 375-385°C such as about 380°C. At these temperatures the yield of depolymerized lignin in a carrier liquid such as VGO (Vacuum Gas Oil) is the highest, Figure 6.

The pressure in the sealed container may be 5bar or higher, or lObar or higher, or 20bar or higher, or 30bar or higher, or 40bar or higher, or 50bar or higher, or 60bar or higher, but preferably not more than 350 bar, or 300bar or lower, or 250bar or lower, or 200bar or lower, or 180bar or lower, or 150bar or lower, or 120bar or lower, or lOObar or lower, or 80 bar or lower, or 65 bar or lower. In one embodiment the pressure is 180-350bar, or 200-300bar. The container is preferably a metal container such as a stainless steel container.

The present method may be performed in air or even in oxygen, Figure 1 1 and 12. In one embodiment the amount of oxygen is O. lmmol or higher, or 0.2mmol or higher, but preferably less than 0.8mmol, or less than 0.6mmol.

The volume amount of aqueous alkali lignin solution in the reactor or container may be 20-80% such as 30-75%, 35-45% or 55-65%.Before the thermal

depolymerization process the alkali aqueous lignin solution (for example black liquor) may be diluted in order to decrease the concentration. A decrease in concentration was found to result in less char formation. A preferred concentration of solid content in the aqueous lignin composition may be 20 weight% or less, or 15 weigh t% or less, such as 10 weight% or less, or 8 weigh t% or less. The lignin content may be 2-10wt% of the black liquor such as 4-8weight%, or 6-7weight%. The present inventors found that by using weak liquor or thin liquor the char formation was reduced in comparison when using concentrated black liquor or thick black liquor. Weak or thin liquor is black liquor obtained from the digester prior to any evaporation (concentration around 15-20 weight%) while concentrated or thick black liquor is liquor obtained after evaporation (concentration around 55- 80 weight%). After the thermal treatment an organic phase and an aqueous phase are formed as well as solid residues (coke and / or char) . The organic phase comprises the depolymerized lignin derivatives and the lignin derivatives may be isolated using any suitable technique such as liquid/ liquid extraction, decantation, distillation, evaporation or centrifugation. The obtained lignin derivatives have also been deoxygenated leaving a product with decreased oxygen content. The solid phase may be separated using any suitable technique such as filtration or decantation.

Liquid/ liquid extraction may be performed using a non-water soluble solvent for example a carrier liquid (such as a mineral oil), benzyl benzoate, various acetates such as methyl acetate, ethyl acetate, cyclopentyl methyl ether and butyl acetate, dichlorom ethane, butyl ether such as tert-butyl methyl ether; diethyl ether, diglyme, diisopropyl ether, dimethoxyethane, diethylene glycol, diethyl ether, polyethylene glycol, 1,4-dioxane and tetrahydrofuran, methylated tetrahydrofuran, mesityl oxide, furfural, isophoroneor toluene as extracting solvent. In one

embodiment the extraction solvent is selected from benzyl benzoate, various acetates such as methyl acetate, ethyl acetate, cyclopentyl methyl ether and butyl acetate such as ethyl acetate. In one embodiment the extraction solvent is a carrier liquid. The extraction is preferably done at an elevated temperature but below the boiling point of the extracting solvent.

The organic phase may be washed with an aqueous solution such as water or acidic water. In one embodiment the acidic water has a pH of 2-6, or 4-5. By doing this the amount of metals in the composition is significantly reduced.

The phenol derivatives obtained from the method may be separated from the product mixture by distillation or liquid /liquid extraction or a combination thereof. The obtained depolymerized lignin may first be extracted using liquid/ liquid extraction followed by distillation. The liquid/ liquid extraction may be done using aromatic or aliphatic hydrocarbon such as benzene, toluene, hexane or pentane as extraction solvent followed by distillation of the extraction solvent. The aqueous phase may comprise lignin or lignin derivatives not soluble in carrier liquids. When the organic phase has been removed the aqueous phase may be thermally treated again using the same conditions or different conditions as in the first thermal treatment step. In another embodiment the aqueous phase may be hydrotreated using a hydrogen donor such as hydrogen gas or formic acid in order to make the lignin or lignin derivatives more soluble in carrier liquids. The obtained hydrotreated lignin or lignin derivatives may be mixed with a carrier liquid and / or combined with the organic phase of the first thermal treatment or the isolated lignin derivative of the first thermal treatment. The hydrotreatment step may be conducted as explained below.

The present inventors surprisingly found that by adding small amounts of alcohols to the black or red liquor prior to the depolymerization step the amount of char formed was significantly reduced, Figure 4. The alcohol is preferably a primary alcohols such as ethanol. The amount equivalents of alcohol to lignin may be 0.1- 10 such as 0.3-6, or 0.5-3. Other alcohols (CI to C20) or mixtures thereof induce the same effect.

The yield of lignin derivative after the thermal depolymerization may be 30-70%, or 40-60%. The yield of bio oil and char are calculated relatively to the amount of acid precipitated lignin from the black liquor. An aliquot of black liquor is treated with sulfuric acid to pH 1 and the precipitate is washed several times with water. The precipitate is dried at 60 °C over night and the obtained residue is considered as a 100% yield by mass. One advantage of the present invention is that a high amount of lignin may be dissolved in a carrier liquid without any use of organic solvents or modifications of the lignin. The amount of lignin derivative in the composition according to the present invention may be 1 weight% or more, or 2 weight% or more, or 4 weight% or more, or 5 weight% or more, or 7 weight% or more, or 10 weight% or more, or 12 weigh t% or more, or 15 weight% or more, or 20 weight% or more, or 25 weigh t% or more, or 30 weight% or more, or 40 weigh t% or more, or 50 weight% or more, or 60 weight% or more, or 70 weight% or more, or 80 weight% or more, or 90 weight% or more. In one embodiment the lignin content is 20-60 weight% such as 30-50 weight% or 35-45 weight%. High amounts of lignin in the composition increases the viscosity of the composition making it hard to pump and treat. The lignin in the composition is non-hydrotreated and still shows high solubility in carrier liquids this is believed to be a result of low oxygen content and the molecular weight.

Any cooking chemicals separated from the lignin derivative composition may be returned to the recovery boiler of the pulp mill. The present method may be integrated into a pulp mill process or into a fuel refinery process.

The composition according to the present invention may be a one phase system. By keeping the composition in motion continuously or regularly the composition may stay in one phase for a prolonged time. Since the composition is meant to be used for example in a refinery the composition will be in motion and thereby it will be a one phase system. In one embodiment the composition is a one phase system at 70°C, preferably also at 25°C, when left for 10 minutes, preferably 30 minutes, preferably 1 hour, preferably when left for 24 hours.

Applications

The present invention may be used for preparing fuel or fuel additive. The

composition according to the present invention may itself be used as a fuel additive. It is believed that the lignin derivative in the composition according to the present invention requires less hydrogen than if lignin would be hydrotreated for example in a slurry cracker or hydro treatment of functionalized lignin (alkylated lignin via esterification for example) dissolved in a carrier liquid.

The composition according to the present invention may be used in a refinery process or in a pre-step to a refinery process for preparing fuel such as diesel and petrol, or diesel and petrol analogues; or biogasoline or biodiesel; or fuel additives. The composition may be treated in a hydrotreater or in a catalytic cracker such as an FCC. The composition may further be used to prepare lubricants or oils. For example synthetic oils with boiling point of at least 359°C. One method of preparing fuel from lignin or lignin derivative that is not soluble in a carrier liquid may comprise dissolving lignin or lignin derivative in an organic solvent and then hydrotreat the obtained solution, fully or partially. Any suitable solvent as described above may be used. Hydrotreated lignin soluble in a carrier liquid is then transferred or added to a carrier liquid before treated in a catalytic cracker for example.

During hydrotreating the feed may be exposed to hydrogen gas (for example 20-200 bar) and a hydrotreating catalyst (NiMo (Nickel Molybdenum), CoMo (Cobalt

Molybdenum) or other HDS, HDN, HDO catalyst) at elevated temperatures (200-500 °C). The hydro treatment process results in hydrodesulfurization (HDS),

hydrodenitrogenation (HDN), and hydrodeoxygenation (HDO) where the sulphurs, nitrogens and oxygens primarily are removed as hydrogen sulfide, ammonia, and water. Hydrotreatment also results in the saturation of olefins and possibly also aromatic compounds. Catalytic cracking is a category of the broader refinery process of cracking. During cracking, large molecules are split into smaller molecules under the influence of heat, catalyst, and/or solvent. There are several sub-categories of cracking which includes thermal cracking, steam cracking, fluid catalyst cracking and

hydrocracking. During thermal cracking the feed is exposed to high temperatures and mainly results in homolytic bond cleavage to produce smaller unsaturated molecules. Steam cracking is a version of thermal cracking where the feed is diluted with steam before being exposed to the high temperature at which cracking occurs. In a fluidized catalytic cracker (FCC) or "cat cracker" the preheated feed is mixed with a hot catalyst and is allowed to react at elevated temperature. The main purpose of the FCC unit is to produce gasoline range hydrocarbons from different types of heavy feeds. During hydrocracking the hydrocarbons are cracked in the presence of hydrogen. Hydrocracking also facilitates the saturation of aromatics and olefins. The hydrotreatment may involve treating the lignin with hydrogen gas or a hydrogen donor in order to obtain a fully or partially hydrogenated product. The hydrogen donor may for example be formic acid or an alcohol or a combination thereof. Suitable alcohols are methanol (MeOH), ethanol (EtOH), propanol, iso- propanol (i-PrOH), glycerol, glycol, butanol, t-butanol (i-BuOH) or combinations thereof. The pressure during the hydrotreatment may be 5 to 400 bar such as 50 bar or higher, or 100 bar or higher, or 300 bar or lower, or 200 bar or lower. The hydrotreatment may be mild due to the lower oxygen content and therefore the hydrogen pressure may be 30-70 bar such as 40-60bar. Since water is generated during the hydrogenation a large amount of energy is released. By using a low hydrogen gas pressure this issue may be handled. The hydrotreatment may be performed at a temperature of not more than 400°C, preferably not more than 300°C, or not more than 200°C. If the lignin is depolymerized a mild

hydrotreatment may be sufficient to increase the solubility in carrier liquids in other words treating the lignin derivative at a temperature under 400°C, or under 300°C, and at a pressure less than 50 bar.

The hydrotreatment may be performed in the presence of a catalyst for example a transition metal catalyst such as an Al, W, Ir, Re, Ni, Mo, Zr, Co, Ru, Rh, Pt or Pd based catalyst. For example Raney nickel, nickel on carbon, Ni/Si, Ni/Fe, Nickel nanopowder, zeolite, amorphous silica-alumina, Pd/ C, NiMo or CoMo or a combination thereof. The most common catalysts are a NiMo or a CoMo catalyst or a combination thereof.

The hydrotreatment may be repeated or a new hydrotreatment step may be performed at other conditions. For example in a first hydrotreatment step the lignin or lignin derivative may be hydrotreated at a temperature of not more than 200°C and at a pressure of less than 40 bar. Then, any hydrotreated lignin or lignin derivative that has become soluble in a carrier liquid may be separated out and the remaining lignin or lignin derivative may then be hydrotreated in a second step, for example at a temperature of not more than 300°C and at a pressure of less than 80 bar. This procedure may be repeated using the same conditions or the temperature and /or pressure may be increased for each additional step. After each

hydrotreatment step hydrotreated products may be extracted using liquid-liquid extraction using any suitable solvent such as ethyl acetate, phenol, toluene or a carrier liquid such as fatty acids or oils, or the hydrotreated products may be separated using filtration or membrane filtration or acid induced precipitation or combination thereof. The hydrotreated products may also be isolated or separated by distillation. During the hydrotreatment hydrogen gas is preferably used but formic acid may also be used.

The hydrotreated product may be further treated in a catalytic cracker or used as fuel or a fuel additive. Any cooking chemicals isolated from the process may be returned to the recovery boiler of the pulp mill plant.

The composition according to the present invention may also be used as an additive, for example as a concreted grinding aid, set retarder for cement, strengthener of cement, antioxidant, enhancer of thermal protection, stabilizer in asphalt, emulsifying agent, fiber strengthening additive, cross-linking agent, board binder, anti-corrosion additive, wear resistant additive, antifriction additive, binder, emulsifier or dispersing agent or for preparing tyres.

The composition may further be used to prepare foams, plastics, rubbers or paint. The esterified lignin may be used as a cross-linking or curing agent, or as a water absorption inhibitor or as a fluidization agent. Mechanical properties may also be enhanced by the use of the composition. The composition may further be used as a raw material for preparing fine chemicals such as aromatic compounds using conventional techniques. The composition may be added to surfaces to obtain dust control, or the composition may be used to prepare batteries.

EXAMPLES

Example 1 General procedure of hydrothermal treating:

A 10 ml stainless steel (316) reactor was charged with fir black liquor (5-6 g) with 19 % DS and in some cases with an additive. The reactor was sealed and heated in a pipe oven for 1 hour at 370, 390 or 410 °C. After cooling in a stream of air the reactor was opened and the contents were treated according to the work up procedures below.

The products were analyzed with GPC, NMR, MALDI-TOF and GC-MS.

Work up procedure A:

The reaction mixture was extracted 3 times with ethyl acetate. A layer separation was achieved in a centrifuge and the organic phase was removed and combined. The combined organic phases were dried over Na₂S0₄ and evaporated to give an oil. The aqueous solution was filtered and the retentate was washed with water and dried. The aqueous phase was evaporated and dried at 60 °C.

Work up procedure B:

As in the work up procedure A, but instead of filtering the aqueous phase it was first acidified with cone. HC1 to pH 2 and extracted 2 times with ethyl acetate. The ethyl acetate extracts were dried over Na₂S0₄ and evaporated. The aqueous solution was filtered and the retantate was washed with water and dried.

Work up procedure C:

The reaction mixture was transferred with ethyl acetate and water to a 50 ml test tube and acidified with HC1 to a pH of 2. After repeated extraction (3 times in total) the combined organic extracts were dried over Na₂S0₄ and evaporated. The aqueous phase was filtered, the insolubles were washed with water and dried. Work up procedure D:

The reaction mixture was filtered and the solid material was washed with water. Distillation of the hydrothermal product:

The hydrothermal oil from the work up procedure A (639 mg) was distilled with a Kugelrohr apparatus to give 348 mg dark yellow oil and 183 mg residue.

Solubility determination:

A carefully weighted sample of the substrate (100 mg) was measured in an HPLC- vial. A carefully weighted amount of solvent (100 mg) was added, the vial was capped and shaken for 30 minutes at 70 °C. After cooling to room temperature the PTFE-cap was changed to a cap with a paper filter and the vial was placed upside down into a conical 15 ml polypropylene plastic tube. The assembly was centrifuged for 10 minutes to filter off the solution. The approximate value of solubility could be calculated from the amount of the obtained solution, Table 1.

Table 1. Solubility results of organic phase in different solvents (carrier liquids).

Solvent Viscosity (cSt) Solubles (wt%) Cone, of LP (wt%)

LGO 72.3 42.1

LGO 68.2 39.7

LGO 74.3 42.7

FAME 94.0 48.5

LCO 90.0 46.2

VGO 43.8 29.9

VGO' 10 79.4 44.3

LGO' 75.3 42.9

LGO" 75.0 42.9

Triglyceride

TOFA 92.5 47.9

3:7 TOFA:LGO 83.7 44.1

LD=lignin derivative, LGO=Light Gas Oil, VGO=Vacuum Gas Oil, FAME =Fatty Acid Methyl Ester, LCO = Light Cycle Oil, TOFA=Tall oil fatty acid

LGO and LGO' as well as VGO, VGO' and VGO" refers to different brands or types of the same class of oil. Example 2

Different black liquors were tested using the method according to the present invention - weak (fir) , concentrated (broadleaf) and a mixture of weak and concentrated (fir /broadleaf). The effect of an added alcohol (ethanol or methanol) was also studied.

3-5g of black liquor with or without alcohol was heated in a 10 ml reactor placed in a tube oven at 410° C for one hour. The product was extracted using ethyl acetate (1^st extraction). The remaining aqueous solution was acidified and extracted with ethyl acetate again (2^nd extraction). The remaining aqueous solution was filtered and the obtained solid material (char) was dried. The presented results are in percent of lignin mass in the black liquor, Figure 3 and 4.

Addition of an alcohol, especially ethanol, resulted in a significant decrease in char formation.

Example 3 Substance: Sample 1 organic phase -EtOAc extracted and dried Elemental analysis:

Carbon 82.03%

Hydrogen 7.98%

Nitrogen 0.12%

Oxygen 6.53%

Sulfur 0.68%

Table 2. ICP results.

Al As B Ca Cd Co ppm ppm ppm ppm ppm ppm ppm

Etyl

acetate

solubles 0,0 9,9 0,0 30,2 24,6 0,0 0,0

Char 1,4 1635 0,0 19,9 756 0,0 9,5

Residue

from aq.

phase 0,0 27,7 0,0 43,0 90,8 0,0 0,0

Cr Cu Fe K Li Mg Mn ppm ppm ppm ppm ppm ppm ppm

Etyl

acetate

solubles 0,0 0,0 15 17 0,0 114 0,0

Char 176 34,0 4118 589 0,0 1 148 609

Residue

from aq.

phase 0,0 3,9 27 17664 0,0 43 22

Mo Na Ni P Pb S Se ppm ppm ppm ppm ppm ppm ppm

Etyl

acetate

solubles 0,0 346 2,3 0,0 0,0 6753 0,0

Char 13,6 9590 467,0 12,8 0,0 9087 0,0

Residue

from aq.

phase 0,0 416171 2,7 75,3 0,0 8766 0,0

Sr Ti V Y Zn

ppm ppm ppm ppm ppm

Etyl

acetate

solubles 0,0 0,0 10,4 0,0 0,0

Char 3,7 2,2 7,6 0,0 29

Residue

from aq.

phase 0,0 0,0 0,0 0,0 21 Most of the sodium is in the aqueous phase together with the char. The oxygen content is only 6% in comparison with in black liquor where it is 30%.

Example 4

A 10 ml stainless steel (316) reactor was charged with black liquor. The reactor was sealed and heated in a pipe oven for 1 hour at 270°C. After cooling in a stream of air the reactor was opened and the contents were treated according to the work up procedures below.

The products were analyzed with GPC, MALDI-TOF and GC-MS.

BL

source Amount Lignin cone. 1^st extr 2^nd extr Char 1^st extr 2^nd extr Char

(g) (%) (mg) (mg) (mg) (%) (%) (%) fir 6 6.76 139 91 65.8 34.3 22.4 16.2 fir 6 6.76 142 80 74.9 35.0 19.7 18.5 Example 5

Red liquor (8.31 g, 67 % DS (dry stubstance)) was diluted twice with water and basified with NaOH (aq, cone.) to pH 12 and finally diluted with water to a total mass of 27.53 g.

A sample of the above solution (6.00 g) was heated in tube furnace at 410 °C. On cooling the reaction afforded aqueous phase with solid organic matter. Repeated extraction with ethyl acetate and centrifugation afforded 163 mg organic material that was partially soluble in oleic acid but insoluble in light gas oil.

Filtration of the aqueous phase and drying of the insolubles gave 103 mg char. Example 6. A set of four 10 ml stainless steel reactors were charged with black liquor (6.00 g in each) and heated at 400 °C in a liquid sand bath for 1 hour. The reactors were cooled to room temperature, and the contents were transferred with ethyl acetate and water to a flask. The bio oil was extracted with ethyl acetate (25 ml, 10 ml). The combined organic phase was washed with water (3x10 ml). Filtration and

evaporation afforded 823 mg of black oil. Analysis of the black oil.

Elemental analysis:

Carbon 80.47%

Hydrogen 8.60%

Nitrogen 0.045%

Oxygen 10.45%

Sulfur 0.53%

An ICP analysis showed a low content of metals (double run):

Al As B Ca Cd Co Cr

396.152 189.042 249.677 317.933 226.502 228.616 267.716

g/g g/g g/g g/g g/g g/g g/g

5 0 5 2 0 0 1

5 0 4 4 0 0 1

Cu Fe K Mg Mn Mo Na

324.754 259.941 766.491 279.553 259.373 281.615 589.592

g/g g/g g/g g/g g/g g/g g/g

2 1 1 1 0 1 10

0 1 2 6 0 0 10

Ni P Pb Se Ti V Y

231.604 177.495 220.353 203.985 334.941 311.071 371.030

g/g g/g g/g g/g g/g g/g g/g

0 0 0 0 1 6 0

Zn Sb S

206.191 206.833 142.503

g/g g/g g/g

1 0 5872

1 0 5650 Example 7

A 10 ml steel reactor was charged with fir black liquor (6.00 g, 16 % DS) and heated at different temperatures (at 340, 360, 370, 380, 390, 400 and 420 °C). The experiments were repeated twice. After cooling the reactor to room temperature the bio oil was extracted with ethyl acetate (2 times, separation of layers was attained by centrifugation) . The organic extracts were dried over NaS0₄, the solvent was evaporated and yield and LGO-solubility were measured according to the procedure in example 1. The aqueous suspension was filtered, the residue was washed with water and dried at 60°C over night to give char. The results are summarized in figures 6, 7 and 8. As can be seen from the graphs the maximal yield of ethyl acetate soluble material is obtained at temperatures of 360-400 °C. The bio oil reaches a plateau in LGO- solubility at and above 380 °C. The char formation reduces at and above 360 °C.

For the bio oil (ethyl acetate extracted product) obtained at 380 °C a M_w of 479 Da was determined by GPC analysis and a content of 4.5 % phenols by GC-MS analysis. A reduced reaction time to 30 minutes gave same amount of phenols (4.5 %).

For the bio oil obtained at 420 °C a M_w of 391 Da was determined by GPC analysis and a content of 9.4 % phenols by GC-MS analysis. A lower reaction temperature (340 °C) gave a product with higher M_w (655 Da) and lower phenol concentration (2.7 %).

Example 8

The reaction was performed as in example 7 at 400 °C and different times (10, 20, 30 and 60 min). The results are summarized in figures 9 and 10. The yield of ethyl acetate soluble product attains a plateau after 20 minutes. The yield of char rises steadily during the 60 minutes. Example 9

The reaction was performed as in example 7 at 380 °C with different atmospheres (argon, air, oxygen giving 0, 0.23 and 1.08 mmol oxygen, respectively) and results are plotted in figures 11 and 12.

As can be seen from the graphs the outcome of the reaction is not affected at low oxygen concentration, however, higher oxygen content decreases the yield of ethyl acetate- and LGO-soluble product while increasing the yield of char. Example 10

The reaction was performed as in example 7 at 380 °C with different amounts of black liquor (4, 6 and 8 g, 6= 1.07). The results are presented in figures 13 and 14.

As can be seen from the graphs the yields of ethyl acetate- and LGO-soluble products have an approximate maximum when reactor is filled with 6 g black liquor. However, the yield of char has no apparent trends.

For the bio oil obtained at 4 g loading a M_w of 509 Da was determined by GPC analysis and a content of 5.6 % phenols by GC-MS analysis, while 8 g loading gave 530 Da and 4.9 % phenols. This reveals another parameter that somewhat affects the outcome of the reaction.

Example 11

The reaction was performed as in example 4 at 410 °C with 6 and 15 month old fir black liquor with 19 % DS. The aging was done in a closed polypropylene bottle at room temperature, without any precautions against atmosphere. The results are summarized in figure 15.

As can be seen from the graph the yield of ethyl acetate soluble product drops significantly with older black liquor and the amount of char somewhat increases.

Example 12

The reaction was performed as in example 7 at 380 °C with alkali lignin solution (6.00 g) prepared by dissolving kraft lignin (0.94 g) in sodium hydroxide solution (1.10 g in 5 ml water) and diluted further with water (to 20.00 g). The workup afforded 104 mg ethyl acetate soluble material (36.9 %) with 39.3 % solubility in LGO giving 14.5 % yield of LGO-soluble material. The reaction produced 5.1 mg char (1.8 %). Example 13

The reaction was performed as in example 4 at 410 °C with kraft lignin (0.41 g) and water (5.59 g). On completion of reaction no ethyl acetate soluble material could be isolated. Example 14

Lignin Phosphitylation Procedure, as described in J. Agric. Food Chem. 1995, 43, 1538.

Bio oil from example 7 obtained at 380 °C (16 mg), Cholesterol (1.74 mg) and Cr(acac)3 (4 mg) were dissolved in a mixture of Pyridine (0.41 mL) and CDCI3 (0.25 mL) and finally of tetramethylphospholane (50 μΐ_^) was added. Phosphorus NMR (³¹P NMR) was run on a Varian 400 MHz (D l = 25 seconds, 1024 scans).

ROH: 0% , ArOH condensed: 4.18 (38%) ArOH: 6.03 (55%) Acids: 0.73 (7%).

1: 19.77 mol ratio was added (monomer Mw 180) and a 1 : 10.94 mol ratio was measured giving that a total of 55% of the monomeric units have an O-H bond.

The result shows that there are essentially no aliphatic alcohols, Figure 23.

Example 15

The reaction was performed as in example 7 at 380 °C with fir black liquor with 12 % DS. The workup afforded 176 mg ethyl acetate soluble material (69.2 %) and 1 1.6 mg char (4.6 %). A M_w of 479 Da was determined by GPC analysis and a content of 12.2 % phenols by GC-MS analysis.

Example 16

The reaction was performed as in example 7 at 380 °C with birch black liquor with

11 % DS. The workup afforded 138 mg ethyl acetate soluble material (72.3 %) and 7.4 mg char (3.9 %). A M_w of 469 Da was determined by GPC analysis and a content of 9.8 % phenols by GC-MS analysis.

Example 17

12 % DS. The workup afforded 145 mg ethyl acetate soluble material (64.8 %) and 12.8 mg char (5.7 %). A M_w of 465 Da was determined by GPC analysis and a content of 10.7 % phenols by GC-MS analysis.

Example 18

The reaction was performed as in example 7 at 380 °C with eucalyptus black liquor with 12 % DS. The workup afforded 127 mg ethyl acetate soluble material (57.2 %) and 14.5 mg char (6.5 %). A M_w of 453 Da was determined by GPC analysis and a content of 8.6 % phenols by GC-MS analysis.

Claims

1. A composition comprising depolymerized Kraft lignin derivatives and a solvent wherein at least 2.5 weight% of the depolymerized lignin derivatives are phenol derivatives having a weight average molecular weight (M_w) of 160g/mol or less.

2. The composition according to claim 1 wherein the lignin derivative has a weight average molecular weight (M_w) of 250g/mol to 650g/mol.

3. The composition according to claim 1 or 2 wherein the solvent is a carrier liquid.

4. The composition according to any one of claims 1 to 3 wherein content of lignin derivative is 1 weight% or more, or 2 weight% or more, or 4 weight% or more, or 5 weight% or more, or 7 weight% or more, or 10 weight% or more, or 12 weight% or more, or 15 weight% or more, or 20 weight% or more, or 25 weight% or more, or 30 weight% or more, or 40 weight% or more, or 50 weight% or more, or 60 weight% or more, or 70 weight% or more, or 75 weight% or more.

5. The composition according to any one of claims 1-4 wherein the content of solvent is at least 20 weight%, or at least 30 weight%, or at least 40 weight%, or at least 50 weight%, or at least 60 weight%, or at least 70 weight%, or at least 80 weight%, or at least 90 weight% of the total composition.

6. The composition according to any one of claims 1-5 wherein the content of lignin derivative is 20 weight% or more and wherein the solvent is a carrier liquid.

7. The composition according to any one of claims 1-6 wherein the weight average molecular weight (M_w) is 300g/mol to 500g/mol.

8. The composition according claim 3 wherein the carrier liquid is a hydrocarbon oil, crude oil, bunker oil or mineral oil.

9. The composition according to claim 1 wherein the solvent is selected from a C2- C15 ketone, such as a C4-C12 ketone, or a C6-C8 ketone or a C1-C10 aldehyde, such as a C4-C9 aldehyde or C6-C8 aldehyde.

10. The composition according to claim 1 wherein the composition further comprises 0.1 to lwt% of added ethanol.

1 1. The composition according to claim 3 wherein the carrier liquid is tall oil, creosote oil, tar oil, fatty acid or esterified fatty acid.

12. The composition according to claim 3 wherein the carrier liquid is a mixture of a hydrocarbon oil and a fatty acid or an esterified fatty acid.

13. The composition according to claim 3 wherein the solvent is a carrier liquid and the lignin derivative has a content of carbon of 70-90%, such as 75-85%, or 80- 83%, hydrogen 5-12%, such as 6-9%, nitrogen 0-0.5% such as 0.1-0.2%, oxygen 3- 10% such as 4-8% or 5-7%, sulfur 0-1% such as 0.4-0.8%.

14. The composition according to claim 1 wherein the solvent is an organic solvent and the lignin derivative has a content of carbon of 70-90%, such as 75-85%, or 80- 83%, hydrogen 5-12%, such as 6-9%, nitrogen 0-0.5% such as 0.1-0.2%, oxygen 3- 10% such as 4-8% or 5-7%, sulfur 0-1% such as 0.4-0.8%.

15. The composition according to any of the preceding claims wherein the total metal content of the composition is less than lOOppm, such as less than 80ppm, or less than 60ppm.

16. The composition according to any of the preceding claims wherein the

composition comprises 3 to 25weight% of phenol derivatives such as 5-8weight%.

17. A method of producing the composition according to any one of claims 1 to 16 comprising: -adding an alkali aqueous lignin solution to a container;

-sealing the container;

-heating the alkali aqueous lignin solution to at least 270 °C in an oxygen containing environment such as air to depolymerize the lignin to a molecular weight of 250- 650g/mol;

-optionally isolating the depolymerized lignin; and

-mixing the depolymerized lignin with a solvent.

18. The method according to claim 17 wherein the solid content in the aqueous alkali lignin solution is 20wt% or less such as 15wt% or less, or 10wt% or less, or 8wt% or less.

19. The method according to claim 17 or 18 wherein the alkali aqueous lignin solution is heated to 375-385°C.

20. The method according any one of claims 17 to 19 wherein an alcohol is added prior to the heating of the alkali aqueous lignin solution.

21. The method according to any one of claims 17 to 20 wherein the aqueous alkali lignin solution is fresh.

22. The method according to any one of claims 17 to 21 wherein the obtained depolymerized lignin is extracted using an extraction solvent prior to mixing the depolymerized lignin with the solvent.

23. The method according to any one of claims 17 to 22 wherein the amount of aqueous alkali lignin solution is 55-65% of the container volume.

24. Use of the composition according to any one of claims 1 to 16 for preparing fuel such as petrol and diesel, or diesel and petrol analogues, or biogasoline or biodiesel; or fuel additives.

25. A method of preparing fuel comprising treating the composition according to any one of claims 1 to 16 in a hydro treater or a catalytic cracker.

26. A fuel obtained by hydrolytical cracking or hydrotreatment of the composition according to any one of claims 1 to 16.

27. A fuel additive comprising the composition according to any one of claims 1 to 16.

28. A fuel comprising the composition according to any one of claims 1 to 16.

29. Use of the composition according to any one of claims 1 to 16 for producing chemicals or paint or tyres.

30. Use of the composition according to any one of claims 1 to 16 as concreted grinding aid, set retarder for cement, strengthener of cement, antioxidant, enhancer of thermal protection, stabilizer in asphalt, emulsifying agent, fiber strengthening additive, cross-linking agent, board binder, anti-corrosion additive, wear resistant additive, antifriction additive, binder, emulsifier or dispersing agent, cross-linking or curing agent, or as a water absorption inhibitor or as a fluidization agent, as an anti-bacterial or anti-fungal surface or as a barrier, to impregnate wood or as an anti-corrosion agent.

31. The fuel or fuel additive according to claim 26 wherein the depolymerized lignin has 14C of below 75 years.

32. The composition according to any one of claims 1 to wherein the depolymerized lignin comprises phenol derivatives having a 14C of below 75 years.