SE542463C2 - Depolymerized lignin in hydrocarbon oil - Google Patents

Abstract

The present invention relates to a method of preparing a composition comprising lignin derivative and a solvent; wherein the lignin derivative has a weight average molecular weight (M) of 250g/mol to 650g/mol, wherein the method comprises treating black or red liquor in a sealed container at 360-420°C.

Description

The present invention relates to a method of preparing a composition of ligninderivative and a hydrocarbon oil . 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, processingwaste, 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 thebiomass. Lignin comprises chains of aromatic and oxygenate constituents forminglarger molecules that are not easily treated. A major reason for diff1culty in treating thelignin 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 ofpreparing lignin is by separation from wood during pulping processes. Only a smallamount (1-2 %) is utilized in specialty products whereas the rest primary serves asfuel. Even if burning lignin is a valuable way to reduce usage of fossil fuel, lignin hassignificant potential as raw material for the sustainable production of chemicals and liquid fuels.

Various lignins differ structurally depending on raw material source and subsequentprocessing, but one common feature is a backbone consisting of various substitutedphenyl propane units that are bound to each other via aryl ether or carbon-carbonlinkages. They are typically substituted with methoxyl groups and the phenolic and aliphatic hydroxyl groups provide sites for e.g. further functionalization. Lignin is 2 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 itmay also be used as an energy source due to its high energf content. Lignin hashigher energf content than cellulose or hemicelluloses and one gram of lignin has onaverage 2.27 KJ, which is 30% more than the energy content of cellulosiccarbohydrate. The energy content of lignin is similar to that of coal. Today, due to itsfuel value lignin that has been removed using the kraft process, sulphate process, in apulp or paper mill, 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 separating lignin from black or red liquor obtained afterseparating the cellulose f1bres in the kraft or sulphite process respectively, during theproduction processes. One of the most common strategies is membrane or ultra-filtration. Lignoboost® is a separation process developed by Innventia AB and theprocess has been shown to increase the lignin yield using less sulphuric acid. In theLignoboost® process, black liquor from the production processes is taken and thelignin is precipitated through the addition and reaction with acid, usually carbondioXide (C02), and the lignin is then filtered off. The lignin filter cake is then re-dispersed and acidified, usually using sulphuric acid, and the obtained slurry is thenfiltered and washed using displacement washing. The lignin is usually then dried andpulverized 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 energi is mainlyderived from biomass material or gases such as wood, corn, sugarcane, animal fat,vegetable oils and so on. However the biofuel industries are struggling With issues likefood vs fuel debate, efficiency and the general supply of raw material. At the same timethe 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 as a fuel or fuel component are to use pyrolysis oils or hydrogenated lignin.

In order to make lignin more useful one has to solve the problem with the lowsolubility of lignin in organic solvents. One drawback of using lignin as a source forfuel production is the issue of providing lignin in a form suitable for hydrotreaters orcrackers. The problem is that lignin is not soluble in oils or fatty acids which is, if not necessary, highly wanted. 3 Prior art provides various strategies for degrading lignin into small units or moleculesin order to prepare lignin derivatives that may be processed. These strategies includehydrogenation, dexoygenation and acid Catalyst hydrolysis. WO201 1003029 relates toa method for catalytic cleavage of carbon-carbon bonds and carbon-oxygen bonds inlignin. US20130025191 relates to a depolymerisation and deoxygenation methodwhere lignin is treated with hydrogen together with a Catalyst in an aromaticcontaining solvent. All these strategies relates to methods where the degradation isperformed prior to eventual miXing in fatty acids or oils. WO2008/ 157164 discloses analternative strategy where a first dispersion agent is used to form a biomasssuspension to obtain a better contact with the catalyst. These strategies usually alsorequires 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 strategf where lignin is modifiedwith an alkyl group via an ester linkage in order to make the lignin more soluble inoils or fatty acids. In WO2014/ 1 16173 the present applicant teaches a composition oflignin 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 followedby a depolymerization step where after the depolymerized lignin is separated. Thedepolymerization 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 anefficient process for preparing the lignin and on the preparation of the lignin or ligninderivatives so that the fuel production is as efficient as possible. For example theamount of oxygen should be as low as possible and the number of preparation stepsshould be as few as possible. A high oxygen content requires more hydrogen during the refinery process.

One way of making fuel production of lignin more beneficial would be if lignin may beprocessed using common oil refinery techniques such catalytic cracking orhydrotreatment. In order to do that the lignin needs to be soluble in refinery media such as hydrocarbon oils.

SUMMARY OF THE INVENTION 4 The object of the present invention is to overcome the drawbacks of the prior art andprovide a composition comprising lignin derivative and a solvent. The lignin derivativeis not only depolymerized it is also deoxygenated fully or partially, i.e. the oxygencontent is reduced. One application for the composition may be as a raw material for fuel production or as an additive to fuel or oil.

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.

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

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 coumarylalcohol, coniferyl alcohol and sinapyl alcohol monomers. Figure 1 discloses a schematic picture of lignin.

In the present application the term “1ignin derivative” means molecules or polymers derived from lignin.

In the present application the term “carrier liquid” means an inert hydrocarbon liquidsuitable for a hydrotreater or a catalytic cracker (cat cracker) a liquid and may beselected 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. 6 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.

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 agiven temperature (usually below 80 °C) or the substance is solvated in a liquid. Inthis patent application, such liquid will be given the term solvent or carrier liquid. Thepresent invention presents a composition and a method of preparing said compositionwhere the composition comprises lignin, where the composition is in liquid phase andmay be processed in a refinery such as an oil refinery. The present invention makes iteasier 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 aperson skilled in the art. The biomass may be treated with pulping processes ororganosolv processes for example. Biomass includes, but is not limited to wood, fruits,vegetables, processing waste, chaff, grain, grasses, corn, corn husks, Weeds, aquaticplants, hay, paper, paper products, recycled paper, shell, brown coal, algae, straw,bark or nut shells, lignocellulosic material, lignin and any cellulose containingbiological material or material of biological origin. In one embodiment the biomass iswood, preferably particulate wood such as saw dust or wood chips. The wood may beany kind of wood, hard or soft wood, coniferous tree or broad-leaf tree. A non-limitinglist 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 Kappanumber estimates the amount of chemicals required during bleaching of wood pulp inorder to obtain a pulp with a given degree of whiteness. Since the amount of bleachneeded is related to the lignin content of the pulp, the Kappa number can be used tomonitor the effectiveness of the lignin-extraction phase of the pulping process. It is approximately proportional to the residual lignin content of the pulp.

Kßc*l K: Kappa number; c: constant = 6.57 (dependent on process and wood), 1: lignincontent in percent. The Kappa number is determined by ISO 302:2004. The kappanumber may be 20 or higher, or 40 or higher, or 60 or higher. In one embodiment thekappa number is 10-100.

The biomass material may be a mixture of biomass materials and in one embodimentthe biomass material is black or red liquor, or materials obtained from black or redliquor. Black and red liquor contains cellulose, hemi cellulose and lignin andderivatives 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 f1ltrated prior todepolymerization. The membrane filtration may be performed using one or moremembranes with different cut offs. Depending on the cut off of the membrane the permeate or the retentate is collected and depolymerized.

The alkali aqueous lignin solution may be solution obtained from a pulp mill forexample black or red liquor. Black liquor comprises four main groups of organicsubstances, around 30-45 weight% ligneous material, 25-35 weight% saccharineacids, about 10 weight% formic and acetic acid, 3-5 weight% extractives, about 1weight% methanol, and many inorganic elements and sulphur. The exact compositionof the liquor varies and depends on the cooking conditions in the production processand the feedstock. Red liquor comprises the ions from the sulfite process (calcium,sodium, magnesium or ammonium), sulfonated lignin, hemicellulose and low molecular resins.

Lignin derivative The lignin derivative according to the present invention is a depolymerized ligninhaving a molecular weight (MW) of 250-650g/ mol. In one embodiment the molecularweight is 270g/mol or higher, or 300g/mol or higher, or 330g/mol or higher, or360g/mol or higher, or 600g/mol or less, or 550g/mol or less, or 500g/mol or less, or480g/ mol or less, or 450g/mol or less, or 400g/ mol or less. The polydispersity is preferably lower than 5, preferably lower than 3, even more preferably lower than 2. 8 Molecular Weight 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 (7.8x3OOmm), Styragel HR 1 THF (7.8x3OO mm), Styragel HR 0.5 THF (7.8x3OO mm) all from Waters.

The lignin derivative according to the present invention has a low oxygen content suchas 10% 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 as75-85%, or 80-83%, hydrogen 5-12%, such as 6-9%, nitrogen O-O.5% such as 0.1-O.2%, oxygen 3-10% such as 4-8% or 5-7%, sulfur O-1% such as O.4-O.8%. Sincemetal residues from the cooking chemicals are not Wanted in the refinery process themetal content should be as low as possible. The lignin derivative according to thepresent invention may have a calcium content of O-70ppm such as 40ppm or less forexample 10-30ppm, iron O-50ppm such as 30ppm or less for example 10-20ppm,potassium O-50ppm such as 30ppm or less for example 10-20ppm, magnesium O-300ppm such as 200ppm or less for example 50-150ppm, sodium O-600ppm such as500ppm or less for example 100-400ppm or 200-300ppm. The ICP analysis (elementalanalysis) is done Wi extraction using ethyl acetate and Wherein the ethyl acetateis removed by evaporation leaving dried lignin derivative. An advantage of the presentinvention is that the lignin in the composition does not have to be hydrotreated duringthe depolymerization step or in an additional step in order to become soluble in a carrier liquid.Solvent According to the present invention the composition comprises a solvent for example a carrier liquid Wherein the carrier liquid is the composition may be used for preparing fuels the carrier liquid does not have to bean already hydrotreated or cracked liquid such as diesel, instead the carrier liquidshould be a liquid that may be hydrotreated or cracked in a refinery process in orderto form fuel. By using a non-hydrotreated or non-cracked carrier liquid conventionalrefinery processes may be used and carrier liquids that any Way Would be ref1ned can be used.

The carrier liquid should preferably be suitable for a hydrotreater or a catalyticcracker (cat cracker), preferably a liquid suitable for both hydrotreater and catalyticcracker. Hydrotreating and catalytic cracking are common steps in the oil ref1neryprocess Where the sulfur, oxygen and nitrogen contents of the oil is reduced andWhere high-boiling, high molecular Weight hydrocarbons are converted into gasoline, diesel and gases.

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. Thesehydrocarbon oils include different types of or gas oils and likevvise 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 clay-treated full-range straight run, distillates full-range atm,distillates hydrotreated full-range, straight-run light, distillates heavy 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 agas 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 aresidual or a mixture of both and the chain length. For example No. 1 fuel oil is adistillate with a chain length of 9-16, No. 2 fuel oil (also known as Bunker A) is adistillate With a chain length of 10-20, No. 4 and No. 5 fuel oil (also known as BunkerB) is a distillate and a residual oil respectively With a chain length of 12-70 and No. 6fuel oil (also known as Bunker C) is a residual (heavy fuel oil) with a chain length of20-70. No. 5 and 6 are also known as heavy fuel oil (HFO) or furnace fuel oil (FFO). Inone embodiment the bunker fuel is a Bunker B. In another embodiment the bunkerfuel 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 ofthe 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%.

Preparation of the composition The present inventors found that by depolymerizing the lignin to small polymeric oroligomeric fractions the solubility of the lignin increased drastically in more non-polar solvents and even in lipophilic solvents such as oils.

The composition according to the present invention may be prepared by first preparingthe lignin derivative followed by mixing said modified lignin With the solvent. Thelignin derivative may be isolated from the depolymerization reaction mixture or thelignin derivative may be left in the reaction mixture when mixed with the carrierliquid. The depolymerization of the lignin may also be performed in the presence of thecarrier liquid. The miXing can be done by stirring or shaking or in any other suitableway 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 processwhere temperature and pressure facilitates the depolymerization of the lignin. Noadded catalyst, such as transition metal catalysts, is necessary. Without being boundbe by theory but the cooking chemicals, the salts or the base, present in the black orred 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 -.-- . ° . -.-- . ° . -.-- . ° . -.-- . Al . -.-- or lower, or 400°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. 13 The pressure in the sealed container may be 5bar or higher, or lObar or higher, or20bar or higher, or 30bar or higher, or 40bar or higher, or 50bar or higher, or 60baror higher, but preferably not more than 200bar, 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.

Before the thermal depolymerization process the alkali aqueous lignin solution (forexample black liquor) may be diluted in order to decrease the concentration. Adecrease in concentration results in less char formation. A preferred concentration ofsolid content in the aqueous lignin composition may be 15 weight% or less, such as 10weight% or less. The present inventors found that by using weak liquor or thin liquorthe char formation was reduced in comparison when using concentrated black liquoror thick black liquor. Weak or thin liquor is black liquor obtained from the digesterprior to any evaporation (concentration around 15-20 weight%) while concentrated orthick 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 aswell as solid residues. The organic phase comprises the lignin derivative and the ligninderivative may be isolated using any suitable technique such as liquid / liquidextraction, decantation evaporation or centrifugation. The obtained lignin derivative isalso deoxygenated. Liquid / liquid extraction may be performed using for example ethylacetate, dichloromethane or toluene as extracting solvent. The aqueous phase maycomprise lignin or lignin derivatives not soluble in carrier liquids. When the organicphase has been removed the aqueous phase may be thermally treated again using thesame conditions or different conditions as in the first thermal treatment step. Inanother embodiment the aqueous phase may be hydrotreated using a hydrogen donorsuch as hydrogen gas or formic acid in order to make the lignin or lignin derivativesmore soluble in carrier liquids. The obtained hydrotreated lignin or lignin derivativesmay be mixed with a carrier liquid and/ or combined with the organic phase of the firstthermal 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 ethanol tothe black or red liquor prior to depolymerization step the amount of char formed was significantly reduced. 14 The yield of lignin derivative after the thermal depolymerization may be 30-70%, or 40-60%. Since the amount of lignin in black liquor is hard to determine the amount of lignin obtained by acid precipitation is considered 100% yield.

One advantage of the present invention is that a high amount of lignin may bedissolved in a carrier liquid Without any use of organic solvents or modif1cations of thelignin. The amount of lignin derivative in the composition according to the presentinvention may be 1 Weight% or more, or 2 Weight% or more, or 4 Weight% or more, or5 Weight% or more, or 7 Weight% or more, or 10 Weight% or more, or 12 Weight% ormore, or 15 Weight% or more, or 20 Weight% or more, or 25 Weight% or more, or 30Weight% or more, or 40 Weight% or more, or 50 Weight% or more, or 60 Weight% ormore, or 70 Weight% or more, or 80 Weight% or more, or 90 Weight% or more. In oneembodiment the lignin content is 20-60 Weight% such as 30-50 Weight% or 35-45Weight%. High amounts of lignin in the composition increases the viscosity of thecomposition 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 bereturned 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. Bykeeping the composition in motion continuously or regularly the composition may stayin one phase for a prolonged time. Since the composition is meant to be used forexample in a refinery the composition Will be in motion and thereby it Will be a onephase 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 1hour, preferably When left for 24 hours.

Applications The present invention may be used for preparing fuel or fuel additive. The compositionaccording to the present invention may itself be used as a fuel additive. It is believedthat 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 hydrotreatment 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 processor in a pre-step to a refinery process for preparing fuel such as diesel and petrol, ordiesel and petrol analogues; or biogasoline or biodiesel; or fuel additives. Thecomposition 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 acarrier liquid may comprise dissolving lignin or lignin derivative in an organic solventand then hydrotreat the obtained solution, fully or partially. Any suitable solvent asdescribed above may be used. Hydrotreated lignin soluble in a carrier liquid is thentransferred 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 20-200bar) and a hydrotreating catalyst (NiMo (Nickel Molybdenum), CoMo (CobaltMolybdenum) or other HDS, HDN, HDO catalyst) at elevated temperatures (200-500°C). The hydrotreatment process results in hydrodesulfurization (HDS),hydrodenitrogenation (HDN), and hydrodeoxygenation (HDO) Where the sulphurs,nitrogens and oxygens primarily are removed as hydrogensulfide, ammonia, and Water. Hydrotreatment also results in the saturation of olefins.

Catalytic cracking is a category of the broader refinery process of cracking. Duringcracking, large molecules are split into smaller molecules under the influence of heat,catalyst, and/ or solvent. There are several sub-categories of cracking Which includesthermal cracking, steam cracking, fluid catalyst cracking and hydrocracking. Duringthermal cracking the feed is exposed to high temperatures and mainly results inhomolytic bond cleavage to produce smaller unsaturated molecules. Steam cracking isa version of thermal cracking Where the feed is diluted With steam before beingexposed to the high temperature at Which cracking occurs. In a fluidized catalyticcracker (FCC) or “cat cracker” the preheated feed is mixed With a hot catalyst and isallowed to react at elevated temperature. The main purpose of the FCC unit is toproduce gasoline range hydrocarbons from different types of heavy feeds. Duringhydrocracking the hydrocarbons are cracked in the presence of hydrogen.

Hydrocracking also facilitates the saturation of aromatics and olefins. 16 The hydrotreatment may involve treating the lignin with hydrogen gas or a hydrogendonor in order to obtain a fully or partially hydrogenated product. The hydrogen donormay for example be formic acid or an alcohol or a combination thereof. Suitablealcohols are methanol (MeOH), ethanol (EtOH), propanol, iso-propanol (i-PrOH),glycerol, glycol, butanol, t-butanol (i-BuOH) or combinations thereof. The pressureduring the hydrotreatment may be 5 to 400 bar such as 50 bar or higher, or 100 baror higher, or 300 bar or lower, or 200 bar or lower. The hydrotreatment may be milddue to the lower oxygen content and therefore the hydrogen pressure may be 30-70bar such as 40-60bar. Since water is generated during the hydrogenation a largeamount of energy is released. By using a low hydrogen gas pressure this issue may behandled. The hydrotreatment may be performed at a temperature of not more than400°C, preferably not more than 300°C, or not more than 200°C. If the lignin isdepolymerized a mild hydrotreatment may be suff1cient to increase the solubility incarrier 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 atransition metal catalyst such as an Al, W, Ir, Re, Ni, Mo, Zr, Co, Ru, Rh, Pt or Pdbased catalyst. For example Raney nickel, nickel on carbon, Ni/ Si, Ni / Fe, Nickelnanopowder, zeolite, amorphous silica-alumina, Pd/ C, NiMo or CoMo or acombination 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 performedat other conditions. For example in a first hydrotreatment step the lignin or ligninderivative may be hydrotreated at a temperature of not more than 200°C and at apressure of less than 40 bar. Then, any hydrotreated lignin or lignin derivative thathas become soluble in a carrier liquid may be separated out and the remaining ligninor lignin derivative may then be hydrotreated in a second step, for example at atemperature of not more than 300°C and at a pressure of less than 80 bar. Thisprocedure may be repeated using the same conditions or the temperature and/ orpressure may be increased for each additional step. After each hydrotreatment stephydrotreated products may be extracted using liquid-liquid extraction using anysuitable solvent such as ethyl acetate, phenol, toluene or a carrier liquid such as fattyacids or oils, or the hydrotreated products may be separated using filtration or membrane filtration or acid induced precipitation or combination thereof. The 17 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 fuelor 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 ofcement, antioxidant, enhancer of thermal protection, stabilizer in asphalt, emulsifyingagent, fiber strengthening additive, cross-linking agent, board binder, anti-corrosionadditive, Wear resistant additive, antifriction additive, binder, emulsif1er or dispersing agent or for preparing tyres.

The composition may further be used to prepare foams, plastics, rubbers or paint. Theesterified lignin may be used as a cross-linking or curing agent, or as a Waterabsorption inhibitor or as a fluidization agent. Mechanical properties may also beenhanced by the use of the composition. The composition may further be used as araw 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.

EXAMPLESExample 1General procedure of hydrothermal treating: A 10 ml stainless steel (316) reactor Was charged With black liquor (5-6 g) and in somecases With an additive. The reactor Was sealed and heated in a pipe oven for 1 hour at300, 320 or 340 °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: 18 The reaction miXture Was extracted 3 times With ethyl acetate. A layer separation Wasachieved in a centrifuge and the organic phase Was removed and combined. Thecombined organic phases Were dried over Na2SO4 and evaporated to give an oil. Theaqueous 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 f1ltering the aqueous phase it Was firstacidified With conc. HCl to pH 2 and extracted 2 times With ethyl acetate. The ethylacetate extracts Were dried over Na2SO4 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 tubeand acidified With HCl to a pH of 2. After repeated extraction (3 times in total) thecombined organic extracts Were dried over Na2SO4 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 aKugelrohr 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 andshaken for 30 minutes at 70 °C. After cooling to room temperature the PTFE-cap Waschanged to a cap With a paper filter and the vial Was placed upside down into a conical15 ml polypropylene plastic tube. The assembly Was centrifuged for 5 minutes to filteroff 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). 19 Solvent VïSCOSílïY (CSÛ Solubles (Wt%) Conc. of LD (Wt%)LGO 72.3 42.1LGO 68.2 39.7LGO 74.3 42.7 FAME 94.0 48.5LCO 90.0 46.2VGO 43.8 29.9VGO, 10 79.4 44.3LGO, 75.3 42.9LGO” 75.0 42.9 TriglycerideTOFA 92.5 47.9327 TOFAíLGO 83.7 44.1 LD=lignin derivative, LGO=Light Gas Oil, VGO=Vacuum Gas Oil, FAME =Fatty AcidMethyl 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 presentinvention - Weak (fir), concentrated (broadleaf) and a mixture of Weak andconcentrated (fir/broadleaf). The effect of an added alcohol (ethanol or methanol) Wasalso studied. 3-5g of black liquor With or Without alcohol Was heated in a 10 ml reactor placed in atube oven at 340°C for one hour. The product Was extracted using ethyl acetate (lstextraction). The remaining aqueous solution Was acidified and extracted With ethylacetate again (Qnd extraction). The remaining aqueous solution Was f1ltered and theobtained 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 Elementary analysis: Carbon 82.03%Hydrogen 7.98%Nitrogen 0.12%Oxygen 6.53%Sulfur 0.68% Table 2. ICP results.

Ca 396.847 Fe 259.941 K 766.491 Mg 279.553 Na 589.592 S 180.731 (3901 139m 139m ppm ppm ppmRFAPZe l63t3 org 24.6 15 17 114 346 6753RFAPZe 16313 re s i d ue 756 4118 589 1148 9590 9087RFAP Ze 16313 a q 90.8 27 17664 43 416171 8766 RFAP1e163t3 org = product from first extraction With ethyl acetateRFAP2e163t3 residue =coke RFAP2e163t3 aq = evaporated aqueous phase Conclusion: Most of the sodium is in the aqueous phase together With the cokes. The oxygen content is only 6% in comparison With in black liquor Where it is 30%.70-80% of the organic phase is soluble in light gas oil (LGO) as seen in the table belowExample 4 A 10 ml stainless steel (316) reactor Was charged With black liquor. The reactor Wassealed and heated in a pipe oven for 1 hour at 270°C. After cooling in a stream of airthe 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 Amoun source t Lignin conc. 1st extr 2f1d extr Char 1st extr 2f1d 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

Claims (21)

- Amended, November 9, 2017 Marked up

1. A composition comprising depolymerized lignin derivative and a solvent; Whereinthe lignin derivative has a Weight average molecular Weight (MW) of 250g/ mol to 650g/mol; Wherein the depolymerized lignin derivative has an oXygen content of 10% or less and Wherein the lignin is obtained from black liquor or red liquor.

2. The composition according to claim 1 Wherein the solvent is a carrier liquid.

3. The composition according to claim 1 or 2 Wherein content of lignin derivative is1 Weight% or more, or 2 Weight% or more, or 4 Weight% or more, or 5 Weight% ormore, or 7 Weight% or more, or 10 Weight% or more, or 12 Weight% or more, or 15Weight% or more, or 20 Weight% or more, or 25 Weight% or more, or 30 Weight% ormore, 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.

4. The composition according to any one of claims 1-3 Wherein the content ofsolvent is at least 20 Weight%, or at least 30 Weight%, or at least 40 Weight%, or atleast 50 Weight%, or at least 60 Weight%, or at least 70 Weight%, or at least 80Weight%, or at least 90 Weight% of the total composition.

5. The composition according to any one of claims 1-4 Wherein the content of lignin derivative is 20 Weight% or more and Wherein the solvent is a carrier liquid.

6. The composition according to any one of claims 1-5 Wherein the Weight average molecular Weight (MW) is 300g/mol to 500g/ mol.

7. The composition according claim 2 Wherein the carrier liquid is a hydrocarbon oil, crude oil, bunker oil or mineral oil.

8. 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.

9. The composition according to claim 1 Wherein the composition further comprises 0.1 to 1Wt% of added ethanol.

10. The composition according to claim 2 Wherein the carrier liquid is tall oil, creosote oil, tar oil, fatty acid or esterified fatty acid.

11. The composition according to claim 2 Wherein the carrier liquid is a miXture of a hydrocarbon oil and a fatty acid or an esterified fatty acid.

12. The composition according to claim 2 Wherein the solvent is a carrier liquid andthe 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 O-O.5% such as 0.1-O.2%, oxygen 3-10% such as 4-8% or 5-7%, sulfur O-1% such as O.4-O.8%.

13. The composition according to claim 1 Wherein the solvent is an organic solventand 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 O-O.5% such as 0.1-O.2%, oxygen 3-10% such as 4-8% or 5-7%, sulfur O-1% such as O.4-O.8%.

14. A method of producing the composition according to any one of claims 1 to 13 comprising: -adding a black liquor or red liquor to a container; -sealing the container; -heating the black or red liquor to 340°C to 420°C to depolymerize the lignin to a molecular Weight of 250-650g/mol forming lignin derivatives; -returning any cooking chemicals separated from the lignin derivative composition to the recovery boiler of the pulp mill; and -mixing the depolymerized lignin With a solvent.

15. Use of the composition according to any one of claims 1 to 13 for preparing fuelsuch as petrol and diesel, or diesel and petrol analogues, or biogasoline or biodiesel; or fuel additives.

16. A method of preparing fuel comprising treating the composition according to any one of claims 1 to 13 in a hydrotreater or a catalytic cracker.

17. A fuel obtained by hydrolytical cracking or hydrotreatment of the composition according to any one of claims 1 to 13.

18. A fuel additive comprising the composition according to any one of claims 1 to 13.

19. A fuel comprising the composition according to any one of claims 1 to 13.

20. Use of the composition according to any one of claims 1 to 13 for producing chemicals or paint or tyres.

21. Use of the composition according to any one of claims 1 to 13 as concretedgrinding aid, set retarder for cement, strengthener of cement, antioxidant, enhancerof thermal protection, stabilizer in asphalt, emulsifying agent, fiber strengtheningadditive, cross-linking agent, board binder, anti-corrosion additive, Wear resistantadditive, antifriction additive, binder, emulsif1er or dispersing agent, cross-linkingor curing agent, or as a Water absorption inhibitor or as a fluidization agent, as ananti-bacterial or anti-fungal surface or as a barrier, to impregnate Wood or as an anti-corrosion agent.