Renewable naphthenic base oil

Abstract

A renewable naphthenic base oil comprising a mixture of mononaphthenic compounds and polynaphthenic compounds, wherein the content of mononaphthenic compounds is below 20 wt.%, based on the renewable naphthenic base oil, and wherein the content of polynaphthenic compounds is greater than 50 wt.%, based on the renewable naphthenic base oil, and wherein at least 85 wt.% of the renewable naphthenic base oil has a boiling point greater than 280C. The renewable naphthenic base oil is preferably generated from hydropyrolysis and hydroconversion of a solid biomass containing lignocellulose. The renewable naphthenic base oil is suitable for use in a transformer oil and / or process oil and / or lubricant composition.

Description

[0001] RENEWABLE NAPHTHENIC BASE OIL

[0002] FIELD OF THE INVENTION

[0003] The present disclosure generally relates to a renewable hydrocarbon for use as a renewable naphthenic base oil. More specifically, the present disclosure relates to a renewable naphthenic base oil derived from hydroprocessing of solid biomass.

[0004] BACKGROUND OF THE INVENTION

[0005] The demand for energy is increasing as a result of worldwide economic growth and development. This increase in the demand for energy has contributed to an increase in the amount of greenhouse gases and the overall carbon footprint. In addition, with increasing demand for naphthenic base oils for applications such as transformer oils and other process oil applications, decreasing reserves of naphthenic crude oil that may be accessed and recovered easily and increasing constraints on carbon footprints of such base oils, it may be desirable to develop routes to produce liquid base oils from renewable resources such as biomass in an efficient manner. Biomass offers a source of renewable carbon. Examples of suitable biomass include vegetable oils, oils obtained from algae and animal fats, deconstruction materials such as pyrolyzed recyclable materials and wood, among others. Therefore, when using naphthenic base oils derived from renewable resources, it may be possible to achieve more sustainable CO2 emissions over petroleum-derived base oils. For renewable base oils to replace all or at least a portion of the carbon-based petroleum-derived base oils, the renewable base oils should meet the required performance and emission specifications of the petroleum-derived base oils.

[0006] US7888542B2 relates to a process for producing a saturated base oil or a base oil component based on hydrocarbons. The process comprises oligomerization and deoxygenation of the feedstock. A biological starting material containing unsaturated carboxylic acids and / or esters of carboxylic acids is preferably used as the feedstock.

[0007] One technique for producing liquid transportation fuels from renewable resources is hydropyrolysis and hydroconversion of a solid biomass, such as a solid biomass containing lignocellulose. In order to maximise efficiency of manufacturing resources, it would also be desirable to use the same process to produce a naphthenic base oil which meets specifications required for base oil products.

[0008] SUMMARY OF THE INVENTION

[0009] According to the present invention there is provided a renewable naphthenic base oil comprising a mixture of mononaphthenic compounds and polynaphthenic compounds, wherein the content of mononaphthenic compounds is below 20 wt.%, based on the renewable naphthenic base oil, and wherein the content of polynaphthenic compounds is greater than 50 wt.%, based on the renewable naphthenic base oil, and wherein at least 85 wt.% of the renewable naphthenic base oil has a boiling point greater than 280°C. In a preferred embodiment, the renewable naphthenic base oil is generated from hydropyrolysis and hydroconversion of a solid biomass containing lignocellulose.

[0010] In another embodiment, a process for producing a renewable naphthenic base oil includes feeding a solid feedstock and hydrogen to a first stage hydropyrolysis reactor. The first stage hydropyrolysis reactor includes one or more deoxygenation catalysts, and the solid feedstock includes a biomass containing lignocellulose. The process also includes hydropyrolysing the solid feedstock in the first stage hydropyrolysis reactor to generate a product stream having partially deoxygenated hydropyrolysis product, H2O, H2, CO2, CO, Ci - C3 gases, char and catalyst fines, feeding at least a portion of the product stream to a second stage hydroconversion reactor having one or more hydroconversion catalysts, hydroconverting the partially deoxygenated hydropyrolysis product in the product stream to generate a vapor phase product having substantially fully deoxygenated hydrocarbon product, H2O, CO, CO2, and Ci - C3 gases, and condensing the vapor phase product to generate a deoxygenated hydrocarbon liquid comprising the substantially fully deoxygenated hydrocarbon product. The substantially fully deoxygenated hydrocarbon product is fractionated into a gasoline product and a distillate product. The distillate product is subjected to hydrotreatment and aromatic saturation steps to produce a naphthene-rich stream. The naphthene rich stream preferably comprises greater than 40 wt.% naphthenes, more preferably greater than 50 wt.% naphthenes, even more preferably greater than 55 wt.% naphthenes, by weight of the naphthene-rich stream. The naphthene-rich stream preferably comprises less than 10 wt.% aromatics. Depending on the application, within the process flexibility the aromatics levels may be from 0.5 wt.% to 7 wt.%, more preferably from 1 to 5 wt.%, based on the renewable naphthenic base oil (as measured according to ASTM D2140). (The distillate product that is subjected to hydrotreatment and aromatics saturation typically contains about 30 wt.% naphthenes and about 30 wt.% aromatics). The naphthene-rich stream is fractionated to produce a kerosene / jet fuel fraction and a renewable naphthenic base oil.

[0011] According to the present invention, there is further provide a transformer oil composition comprising the renewable naphthenic base oil described herein.

[0012] According to the present invention, there is further provided a process oil composition comprising the renewable naphthenic base oil described herein.

[0013] According to the present invention, there is further provided a lubricant composition comprising the renewable naphthenic base oil described herein.

[0014] Despite the high oxygen content of the solid biomass starting material relative to that of naphthenic crude (e.g. the oxygen content of pinewood is typically 43 wt.% compared to an oxygen content of typically 0.3 wt.% for naphthenic crude), the final renewable naphthenic base oil of the present invention is of high purity and has a very high oxidative stability. This is unexpected in view of the fact that wood consists of high quantities of water and dry wood typically consists of about 50 wt.% carbon, 43 wt.% oxygen, 6 wt.% hydrogen, and 1 wt.% nitrogen and others, while naphthenic crude oil typically consists of 83-87 wt.% carbon, 10 to 14 wt.% hydrogen, 0.1 to 2 wt.% nitrogen, 0.1-1.5 wt.% oxygen, 0.5 to 6 wt.% sulfur, <0.1 wt.% metals. Hence the renewable naphthenic base oil of the present invention is of comparable quality to a naphthenic crude-derived base oil, but with a reduced carbon footprint.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Advantages of the disclosure may become apparent upon reading the following detailed description and upon reference to the drawings in which:

[0017] FIG. 1 is a hydroprocessing system having a first stage and a second stage used to produce a renewable naphthenic base oil from biomass, in accordance with an embodiment of the present disclosure. DETAILED DESCRIPTION

[0018] One or more specific embodiments of the present disclosure will be described below. These described embodiments are examples of the presently disclosed techniques. Additionally, in an effort to provide a concise description of these embodiments, not all features of an actual implementation may be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions will be made to achieve the developers’ specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.

[0019] When introducing elements of various embodiments of the present disclosure, the articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.

[0020] The terms “approximately,” “about,” and “substantially” as used herein represent an amount close to the stated amount that still performs a desired function or achieves a desired result. For example, the terms “approximately,” “about,” and “substantially” may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of a stated amount.

[0021] DEFINITIONS

[0022] The terms “linear paraffins” and “normal paraffins” or “ / / -paraffins” as used herein are intended to denote long straight chain saturated hydrocarbons such as, for example, normal hexadecane (n-C 16). The term “non-linear paraffins” as used herein is intended to denote saturated branched hydrocarbons such as, for example, secondary paraffins and tertiary paraffins. The term “iso-paraffins” as used herein is intended to denote secondary non-cyclic branched paraffins such as, for example, iso-hexadecane (i-C 16). The term “unsaturated hydrocarbons” as used herein is intended to denote hydrogen deficient hydrocarbons such as, for example, olefins, and aromatics.

[0023] The renewable naphthenic base oil of the present invention is preferably produced by a hydroprocessing of a solid feedstock. Hydroprocessing is a catalytic process that includes hydropyrolysis, hydroconversion and / or hydrotreating of certain carbon-containing materials to generate hydrocarbon fuels. Carbon-containing materials that may be used to generate renewable naphthenic base oils via hydroprocessing include solid feedstocks from renewable resources such as, for example, biomass and waste plastics, especially those containing rings, e.g. polystyrene.

[0024] Solid biomass feedstock such as lignocellulosic materials (e.g., wood), among others, are highly cyclic (e.g., greater than 75 wt.% of hydrocarbons are in rings). For example, the lignocellulosic materials include cyclic compounds such as aromatics, non-aromatics, and carbohydrates. As such, these highly cyclic feedstocks result in renewable base oils having nonlinear and cyclic paraffins which results in cold flow properties suitable for cold climates (e.g., climates where ambient temperatures may fall below freezing temperature of water, 0 °C). Besides these cyclic paraffins or naphthenes, these renewable base oils also contain olefinic cyclic compounds and aromatics, as well as linear and branched paraffins (n-paraffins and i-paraffms). Accordingly, these renewable base oils may undergo additional processing and / or include additives to upgrade and yield commercially suitable renewable base oils.

[0025] The renewable naphthenic base oil of the present invention has a high cyclic hydrocarbon content, preferably having a carbon distribution in which at least 50 wt.% of the renewable naphthenic base oil is naphthenic carbons. The renewable naphthenic base oil comprises a mixture of mononaphthenic compounds and polynaphthenic compounds. The amount of mononaphthenic compounds present in the renewable naphthenic base oil is below 20 wt.%, preferably in the range from 3 wt.% to 12 wt.%, more preferably from 4 wt.% to 10 wt.%, based on the renewable naphthenic base oil. The amount of polynaphthenic compounds in the renewable naphthenic base oil is greater than 50 wt.%, preferably in the range from 52 wt.% to 90 wt.%, more preferably in the range from 60 wt.% to 85 wt.%, based on the renewable naphthenic base oil. As used herein, the term ‘polynaphthenic compounds’ includes dinaphthenic compounds, trinaphthenic compounds, and naphthenic compounds containing more than three naphthenic rings. As used herein, the term ‘trinaphthenic plus compounds’ (or tri+ naphthenic compounds) means naphthenic compounds containing three or more naphthenic rings. In a preferred embodiment, the polynaphthenic compounds comprise a mixture of dinaphthenic compounds and trinaphthenic plus compounds, wherein the amount of dinaphthenic compounds is 20 wt.% or greater, preferably from 25 wt.% to 40 wt.%, and the amount of trinaphthenic plus compounds is 25 wt.% or greater, preferably from 30 wt.% to 60 wt.%, based on the renewable naphthenic base oil.

[0026] The renewable naphthenic base oil of the present invention has a carbon distribution such that the sum of Ca + Cn, (where Ca is the amount of carbon atoms in aromatic rings and Cn is the amount of carbon atoms in naphthenic rings) is in the range from 55% to 65%, preferably from 56% to 60% (according to ASTM D2140).

[0027] At least 85 wt.% of the renewable naphthenic base oil has a boiling point greater than 280°C. Preferably at least 90 wt.% of the renewable naphthenic base oil has a boiling point greater than 280°C. In a preferred embodiment, at least 95 wt.% of the renewable naphthenic base oil has a boiling point greater than 280°C. In other words, the renewable naphthenic base oil has a T15 greater than 280°C, preferably a T10 greater than 280°C, more preferably a T5 greater than 280°C.

[0028] Preferably, the renewable naphthenic base oil has an initial boiling point of greater than 230°C. Preferably, the renewable naphthenic base oil has a final boiling point of less than 500°C. In other words, the renewable naphthenic base oil preferably has an initial boiling point of TO greater than 230°C and / or the renewable naphthenic base oil preferably has a final boiling point of T100 less than 500°C.

[0029] The naphthenic base oils generated via catalytic hydropyrolysis and hydroconversion of solid biomass feedstock are generally dense. The renewable naphthenic base oils of the present invention preferably have a density at 15°C of greater than approximately 860 kilograms, preferably in the range from 860 to 895 kg / m3, more preferably from 865 to 895 kg / m3, even more preferably from 870 to 890 kg / m3. In addition, the renewable naphthenic base oils of the present invention have a low amount of linear paraffinic compounds (e.g., less than approximately 20 wt.%), and an even lower content of isoparaffins (e.g. less than approximately 8 wt.%).

[0030] The dynamic viscosity of the renewable naphthenic base oils of the present invention is relatively high, preferably greater than 4.5 mm2 / s, more preferably greater than 5 mm2 / s at 40°C. Preferably, the renewable naphthenic base oil has a dynamic viscosity at 40°C of less than 12 mm2 / s.

[0031] The renewable naphthenic base oil of the present invention preferably has a very low oxygen content, preferably <0.06 wt.% oxygen, based on the renewable naphthenic base oil. Further, the renewable naphthenic base oil of the present invention preferably has a low sulfur content and a low nitrogen content. In one embodiment, the sulfur content is 2.5 ppmw or lower, and the nitrogen content is 2.5 ppmw or lower. Hence, with the renewable naphthenic base oil of the present invention, we are still achieving the same quality as a naphthenic base oil derived from naphthenic crude oil, but with a reduced carbon footprint.

[0032] With the foregoing in mind, FIG. l is a block diagram of an embodiment of a system 10 that may be used for hydroprocessing solid feedstocks (e.g., biomass and / or waste plastics / oils) to generate one or more hydrocarbon products (e.g., GO / diesel, gasoline, kerosene, base oil, etc.) used to generate the renewable naphthenic base oil disclosed herein. As should be appreciated, the solid feedstock-derived hydrocarbon products disclosed herein may be generated by any suitable hydroprocessing technique such as those disclosed in U.S. Patent No. 9,447,328, which is hereby incorporated by reference in its entirety. In the illustrated embodiment, the system 10 includes a hydropyrolysis reactor 14 and a hydroconversion reactor 16. As discussed in further detail below, the reactors 14, 16 are used to convert a solid feedstock into an intermediate hydrocarbon base oil fraction. As illustrated, the reactors 14, 16 are disposed within one of two stages. For example, the system 10 includes a first stage 18 and a second stage 20. The first stage 18 includes the hydropyrolysis reactor 14, and the second stage 20 includes the hydroconversion reactor 16. The reaction pressure in the first stage 18 and the second stage 20 may be varied to tailor the boiling point distribution and composition of the resultant hydrocarbon product(s) generated by the second stage 18. The ability to tailor the boiling point distribution and / or composition of the resultant hydrocarbon product by varying the reaction pressure may provide an efficient process for generating commercially viable hydrocarbon base oils that meet the different requirements set forth by the location and / or market in which the hydrocarbon base oil will be used. For example, when the reaction pressure is less than approximately 0.6 megapascals (MPa) the occurrence of undesirable olefin and / or aromatic saturation reactions may be decreased compared to when the reaction pressure is above 2.0 MPa. However, certain base oil parameters may still not be at a desired level to meet specifications set forth for commercial naphthenic base oils. Therefore, the base oil fraction may need to undergo additional processing (e.g., hydropolishing) to upgrade the base oil and to increase its naphthenes content.

[0033] First Stage

[0034] In the illustrated embodiment, a solid feedstock 24 having biomass (e.g., lignocellulose) and / or waste plastics and molecular hydrogen (H2) 28 are introduced into the hydropyrolysis reactor 14. The hydropyrolysis reactor 14 contains a deoxygenation catalyst that facilitates partial deoxygenation of the solid feedstock 24. For example, in the hydropyrolysis reactor 14, the solid feedstock 24 undergoes hydropyrolysis, producing an output 30 having char, partially deoxygenated products of hydropyrolysis, light gases (Ci - C3 gases, carbon monoxide (CO), carbon dioxide (CO2), and H2), water (H2O) vapor and catalyst fines. The hydropyrolysis reactor 14 may be a fluidized bed reactor (e.g., a fluidized bubbling bed reactor), fixed-bed reactor, or any other suitable reactor. In embodiments in which the hydropyrolysis reactor 14 is a fluidized bed reactor, the fluidization velocity, catalyst particle size and bulk density and solid feedstock particle size and bulk density are selected such that the deoxygenation catalyst remains in the bubbling fluidized bed, while the char produced is entrained with the partially deoxygenated products (e.g., the output 30) exiting the hydropyrolysis reactor 14. The hydropyrolysis step in the first stage 18 employs a rapid heat up of the solid feedstock 24 such that a residence time of the pyrolysis vapors in the hydropyrolysis reactor 14 is preferably less than approximately 1 minute, more preferably less than approximately 30 seconds and most preferably less than approximately 10 seconds.

[0035] The solid feedstock 24 used in the disclosed process may include a residual waste feedstock and / or a biomass feedstock containing lignin, lignocellulosic, cellulosic, hemicellulosic material, or any combination thereof. Lignocellulosic material may include a mixture of lignin, cellulose and hemicelluloses in any proportion and also contains ash and moisture. Such material is more difficult to convert into fungible liquid hydrocarbon products than cellulosic and hemicellulosic material. It is an advantage of the present process that it can be used for lignocellulose-containing biomass. Therefore, the solid feedstock 24 used in the disclosed process preferably contains lignocellulosic material. Suitable lignocellulose-containing biomass includes woody biomass and agricultural and forestry products and residues (whole harvest energy crops, round wood, forest slash, bamboo, sawdust, bagasse, sugarcane tops and trash, cotton stalks, corn stover, corn cobs, castor stalks, Jatropha whole harvest, Jatropha trimmings, de-oiled cakes of palm, castor and Jatropha, coconut shells, residues derived from edible nut production and mixtures thereof), and municipal solid wastes containing lignocellulosic material. The municipal solid waste may include any combination of lignocellulosic material (yard trimmings, pressure-treated wood such as fence posts, plywood), discarded paper and cardboard and waste plastics, along with refractories such as glass, metal. Prior to use in the process disclosed herein, municipal solid waste may be optionally converted into pellet or briquette form. The pellets or briquettes are commonly referred to as Refuse Derived Fuel in the industry. Certain feedstocks (such as algae and lemna) may also contain protein and lipids in addition to lignocellulose. Residual waste feedstocks are those having mainly waste plastics. In a preferred embodiment of the process disclosed herein, woody biomass, preferably wood, is used as the source of the biomass.

[0036] The solid feedstock 24 may be provided to the hydropyrolysis reactor 14 in the form of loose biomass particles having a majority of particles preferably less than about 3.5 millimeters (mm) in size or in the form of a biomass / liquid slurry. However, as appreciated by those skilled in the art, the solid feedstock 24 may be pre-treated or otherwise processed in a manner such that larger particle sizes may be accommodated. Suitable means for introducing the solid feedstock 24 into the hydropyrolysis reactor 14 include, but are not limited to, an auger, fast-moving (greater than about 5 minutes (m) / second (sec)) stream of carrier gas (such as inert gases and H2), and constant-displacement pumps, impellers, turbine pumps or the like. In an embodiment of the present disclosure, a double-screw system having a slow screw for metering the solid feedstock 24 followed by a fast screw to push the solid feedstock 24 into the reactor without causing torrefaction in the screw housing is used for dosing. An inert gas or hydrogen flow is maintained over the fast screw to further reduce the residence time of the solid feedstock 24 in the fast screw housing. The hydropyrolysis step is carried out in the hydropyrolysis reactor 14 at a temperature in the range of from approximately 350 Celsius (°C) to approximately 600 °C and a pressure in the range of from approximately 1 megapascal (MPa) to approximately 6 MPa (approximately 10-60 bar). The heating rate of the solid feedstock 24 is preferably greater than about 100 watts / meter2(W / m2). The weight hourly space velocity (WHSV) in grams (g) biomass / g catalyst / hour (h) for the hydropyrolysis step is in the range of from approximately 0.2 h'1to approximately 10 h’1, preferably in the range of from approximately 0.3 h'1to 3 h'1.

[0037] The hydropyrolysis step may operate at a temperature between approximately 300 °C and 650 °C. The temperatures used in hydropyrolysis rapidly devolatilize the solid feedstock 24. Thus, in a preferred embodiment, the hydropyrolysis step includes the use of an active catalyst (e.g., a deoxygenation catalyst) to stabilize the hydropyrolysis vapors. The activity of the catalyst used herein remains high and stable over a long period of time such that it does not rapidly coke. Catalyst particle sizes, for use in the hydropyrolysis reactor 14, are preferably in the range of from approximately 0.3 millimeter (mm) to approximately 4.0 mm, more preferably in the range of from approximately 0.6 mm to approximately 3.0 mm, and most preferably in the range of from approximately 1 mm to approximately 2.4 mm.

[0038] Any deoxygenation catalyst suitable for use in the temperature range of the hydropyrolysis process may be used. Preferably, the deoxygenation catalyst is selected from sulfided catalysts having one or more metals from the group consisting of nickel (Ni), cobalt (Co), molybdenum (Mo) or tungsten (W) supported on a metal oxide. Suitable metal combinations include sulfided NiMo, sulfided CoMo, sulfided NiW, sulfided CoW and sulfided ternary metal systems having any 3 metals from the family consisting of Ni, Co, Mo and W. Monometallic catalysts such as sulfided Mo, sulfided Ni and sulfided W are also suitable for use. Metal combinations for the deoxygenation catalyst used in accordance with certain embodiments of the present disclosure include sulfided NiMo and sulfided CoMo. Supports for the sulfided metal catalysts include metal oxides such as, but not limited to, alumina, silica, titania, ceria and zirconia. Binary oxides such as silica-alumina, silica-titania and ceria-zirconia may also be used. Preferably, the supports include alumina, silica and titania. In certain embodiments, the support contains recycled, regenerated and revitalized fines of spent hydrotreating catalysts (e.g., fines of CoMo on oxidic supports, NiMo on oxidic supports and fines of hydrocracking catalysts containing NiW on a mixture of oxidic carriers and zeolites). Total metal loadings on the deoxygenation catalyst are preferably in the range of from approximately 1.5 wt.% to approximately 50 wt.% expressed as a weight percentage of calcined deoxygenation catalyst in oxidic form (e.g., weight percentage of Ni (as NiO) and Mo (as MoOs) on calcined oxidized NiMo on alumina support). Additional elements such as phosphorous (P) may be incorporated into the deoxygenation catalyst to improve the dispersion of the metal.

[0039] The first stage of the process disclosed herein produces the output 30 having a partially deoxygenated hydropyrolysis product. The term “partially deoxygenated” as used herein denotes a material in which at least 30 weight % (wt.%), preferably at least 50 wt.%, more preferably at least 70 wt.% of the oxygen present in the original solid feedstock 24 (e.g., lignocelluloses- containing biomass) has been removed. The extent of oxygen removal refers to the percentage of the oxygen in the solid feedstock 24 (e.g., biomass), excluding that contained in the free moisture in the solid feedstock 24. This oxygen is removed in the form of water (H2O), carbon monoxide (CO) and carbon dioxide (CO2) in the hydropyrolysis step. Although it is possible that nearly 100 wt.% of the oxygen present in the solid feedstock 24 is removed, generally at most 99 wt.%, suitably at most 95 wt.% will be removed in the hydropyrolysis step.

[0040] Char Removal

[0041] As discussed above, the output 30 produced from the hydropyrolysis step in the hydropyrolysis reactor 14 includes a mixed solid and vapor product that includes char, ash, catalyst fines, partially deoxygenated hydropyrolysis product, light gases (Ci - C3 gases, CO, CO2, hydrogen sulfide (H2S), ammonia (NH3) and H2), H2O vapor, vapors of C4+ hydrocarbons and oxygenated hydrocarbons. Char, ash and catalyst fines are entrained with the vapor phase product. Therefore, between the hydropyrolysis and hydroconversion steps, the first stage 18 and the second stage 20, respectively, char and catalyst fines are removed from the vapor phase product (e.g., the partially deoxygenated hydropyrolysis product). Any ash present may also be removed at this stage.

[0042] In certain embodiments, the hydropyrolysis reactor 14 may include solid separation equipment (e.g., cyclones), for example above a dense bed phase, to mitigate the entrainment of solid particles above a certain particle size. In addition, or alternatively, the solid separation equipment may be positioned downstream from the hydropyrolysis reactor 14 that removes the char and other solids in the output 30 to generate a vapor phase product 34. For example, as illustrated in FIG. 1, the output 30 is fed to a solid separator 36 that separates / removes the solids (e.g., char, ash and catalyst fines 38) from the output 30. The char and catalyst fines 38 may be removed from the output 30 by cyclone separation, filtering, electrostatic precipitation, inertial separation, magnetic separation, or any other suitable solid separation technique and combinations thereof. In one embodiment, the solid separator 36 includes one or more cyclones. For example, char may be removed by filtration from the vapor stream (e.g., the output 30) or by way of filtering from a wash step-ebullated bed. Back pulsing may be employed in removing char and other solids from the filters as long as hydrogen used in the disclosed process sufficiently reduces the reactivity of the pyrolysis vapors and renders the char free-flowing.

[0043] In other embodiments, the solid separator 36 includes one or more filters or a combination of cyclones, filters and other suitable solid separation equipment to remove the entrained solids from the output 30. For example, the char 38 and other solids may be removed by cyclone separation followed by hot gas filtration. The hot gas filtration removes fines not removed in the cyclones. In this embodiment, the dust cake caught on the filters is more easily cleaned compared to the char removed in the hot filtration of the aerosols produced in conventional fast pyrolysis because the hydrogen from the hydropyrolysis step stabilizes the free radicals and saturated the olefins. In accordance with another embodiment of the present disclosure, cyclone separation followed by trapping the char and catalyst fines 38 in a high-porosity solid adsorbent bed is used to remove the char and catalyst fines 38 from the output 30. By way of non-limiting example, high-porosity solid adsorbents suitable for trapping the char and catalyst fines 38 include alumina silicate materials. Inert graded bed and / or filter materials may also be used to remove the char and catalyst fines 38 from the output 30 to generate the vapour phase product 34.

[0044] The char and catalyst fines 38 may also be removed by bubbling the first stage product gas (e.g., the output 30) through a re-circulating liquid. The re-circulated liquid includes a high boiling point portion of a finished oil from this process (e.g., from the second stage 20) and is thus a fully saturated (hydrogenated), stabilized oil having a boiling point above approximately 370 °C. In certain embodiments, the finished oil may be a heavy oil generated in a separate process. The char or catalyst fines 38 from the first stage 18 are captured in this liquid. A portion of the liquid may be filtered to remove the fines 38 and a portion may be re-circulated back to the hydropyrolysis reactor 14. By using a re-circulating liquid, the temperature of the char-laden process vapors from the first stage 18 is lowered to a temperature suitable for the hydroconversion step in the second stage 20, while also removing fine particulates of char and catalyst. Additionally, employing liquid filtration avoids the use of hot gas filtration.

[0045] In accordance with another embodiment of the present disclosure, large-size NiMo or CoMo catalysts, deployed in an ebullated bed, are used for char removal to provide further deoxygenation simultaneous with the removal of fine particulates. Particles of this catalyst should be large, preferably in the range of from 15 to 30 mm in size, thereby rendering them easily separable from the fine char carried over from the hydropyrolysis reactor 14, which is generally less than 200 mesh (smaller than 70 micrometers (pm).

[0046] Second Stage

[0047] Following removal of the char and catalyst fines 38, the vapor phase product 34 (e.g., the partially deoxygenated hydropyrolysis product) together with the H2, CO, CO2, H2O, and Ci - C3 gases from the hydropyrolysis step (e.g., the first stage 18) are fed into the hydroconversion reactor 16 in the second stage 20 and subjected to a hydroconversion step. The hydroconversion step is carried out at a temperature in the range of from approximately 300 °C to approximately 600 °C and a pressure in the range of from approximately 1 MPa to approximately 6 MPa. As should be noted, pressures higher than 6 MPa may be used to tailor the boiling point distribution and composition of the resultant hydrocarbon product based on the desired specifications of the hydrocarbon base oil produced by the hydroprocessing. The weight hourly space velocity (WHSV) for this step is in the range of approximately 0.1 h'1to approximately 2 h’1. The hydroconversion reactor 16 is a fixed bed reactor. However, in certain embodiments, the hydroconversion reactor 16 may be a fluidized bed reactor. The vapor phase product 34 undergoes hydroconversion in the presence of a hydroconversion catalyst to generate a fully deoxygenated hydrocarbon product 42. The term “fully deoxygenated” as used herein denotes a material in which at least 98 wt.%, preferably at least 99 wt.%, more preferably at least 99.9 wt.% of the oxygen present in the original solid feedstock 24 (e.g., lignocelluloses-containing biomass) has been removed. The hydrocarbon product 42 contains light gaseous hydrocarbons, such as methane, ethane, ethylene, propane and propylene, naphtha range hydrocarbons, middle-distillate range hydrocarbons, hydrocarbons boiling above 370 °C (based on ASTM D86), hydrogen and by-products of the hydroconversion reactions such as H2O, H2S, NH3, CO and CO2.

[0048] The solid feedstock 24 used in the disclosed processes may contain metals such as, but not limited to, sodium (Na), potassium (K), calcium (Ca) and phosphorus (P). These metals may poison the hydroconversion catalyst used in the second stage 20. However, these metals may be removed with the char and ash products (e.g., the char and catalyst fines 38) in the first stage 18. Accordingly, the hydroconversion catalyst used in the hydroconversion step is protected from Na, K, Ca, P, and other metals present in the solid feedstock 24 which may otherwise poison the hydroconversion catalyst. Moreover, by hydropyrolysis of the solid feedstock 24 in the first stage 18, the hydroconversion catalyst is advantageously protected from olefins and free radicals. The conditions under which hydropyrolysis occurs in the first stage 18 stabilize free radicals generated during high temperature devolatilization of the solid feedstock 24 (e.g., biomass) by the presence of hydrogen and catalyst, thereby generating stable hydrocarbon molecules that are less prone to, for example, coke formation reactions which may deactivate the catalyst.

[0049] The hydroconversion catalyst used in the hydroconversion step includes any suitable hydroconversion catalyst having a desired activity in the temperature range of the disclosed hydroconversion process. For example, the hydroconversion catalyst is selected from sulfided catalysts having one or more metals from the group consisting of Ni, Co, Mo or W supported on a metal oxide. Suitable metal combinations include sulfided NiMo, sulfided C0M0, sulfided NiW, sulfided CoW and sulfided ternary metal systems having any three metals from the family consisting of Ni, Co, Mo and W. Catalysts such as sulfided Mo, sulfided Ni and sulfided W are also suitable for use. The metal oxide supports for the sulfided metal catalysts include, but are not limited to, alumina, silica, titania, ceria, zirconia, as well as binary oxides such as silica-alumina, silica-titania and ceria-zirconia. Preferred supports include alumina, silica and titania. The support may optionally contain regenerated and revitalized fines of spent hydrotreating catalysts (e.g., fines of C0M0 on oxidic supports, NiMo on oxidic supports and fines of hydrocracking catalysts containing NiW on a mixture of oxidic carriers and zeolites). Total metal loadings on the catalyst are in the range of from approximately 5 wt.% to approximately 35 wt.% (expressed as a weight percentage of calcined catalyst in oxidic form, e.g., weight percentage of nickel (as NiO) and molybdenum (as MoOs) on calcined oxidized NiMo on alumina catalyst). Additional elements such as phosphorous (P) may be incorporated into the catalyst to improve the dispersion of the metal. Metals can be introduced on the support by impregnation or co-mulling or a combination of both techniques. The hydroconversion catalyst used in the hydroconversion step may be, in composition, the same as or different to the deoxygenation catalyst used in the hydropyrolysis step (e.g., first stage 18). In one embodiment of the present disclosure, the hydropyrolysis catalyst includes sulfided C0M0 on alumina support and the hydroconversion catalyst includes sulfided NiMo on alumina support.

[0050] Following the hydroconversion step, the fully deoxygenated hydrocarbon product 42 is fed to one or more condensers that condenses the hydrocarbon product 42. The condensed hydrocarbon product 42 is fed to a gas-liquid separator 50 to provide a liquid phase product 52 having substantially fully deoxygenated C4+ hydrocarbon liquid and aqueous material. The term “substantially fully deoxygenated” is used herein to denote a material in which at least 90 wt.% to 99 wt.% of the oxygen present in the original lignocellulose containing biomass (e.g., the solid feedstock 24) has been removed. Accordingly, the resulting liquid phase product 52 (e.g., the substantially fully deoxygenated hydrocarbon C4+ liquid) contains less than 2 wt.%, preferably less than 1 wt.%, and most preferably less than 0.1 wt.% oxygen. The substantially fully deoxygenated C4+ hydrocarbon liquid is compositionally different from bio-oil that is generated using other low pressure hydroprocesses. For example, the oxygen content of bio-oil is greater (e.g., between approximately 5 wt.% to 15 wt.%) compared to the liquid phase product 52 (e.g., less than 2 wt.%). Therefore, due, in part, to the lower oxygen content of the liquid phase product 52, an amount of acid components (as measured by total acid number) and polar compounds is decreased compared to the bio-oil. By way of non-limiting example, the acid components include carboxylic acids, phenols and mixtures thereof.

[0051] The liquid phase product 52 undergoes a separation process in the gas-liquid separator 50 that separates and removes the aqueous material from the substantially fully deoxygenated C4+ hydrocarbon liquid. Any suitable phase separation technique may be used to separate and remove the aqueous material from the substantially fully deoxygenated C4+ hydrocarbon liquid, thereby generating the liquid phase product 52 having the substantially fully deoxygenated C4+ hydrocarbon and non-condensable gases 54. The non-condensable gases 54 includes mainly H2, CO, CO2 and light hydrocarbon gases (typically Ci to C3 and may also contain some C4+ hydrocarbons).

[0052] In certain embodiments, the non-condensable gases 54 are fed to a gas clean-up system 58. The gas clean-up system 58 removes H2S, NH3 and trace amounts of organic sulfur-containing compounds, if present, as by-products of the process, thereby generating a hydrocarbon stream 60 having CO, CO2, H2 and the light hydrocarbon gases. The gas clean-up system 58 includes one or more process units that remove H2S 62 and NH3 64 from the non-condensable gases 54 as byproducts of the process. The hydrocarbon stream 60 may be sent to a separation, reforming and water-gas shift section 68 where hydrogen 28 is produced from the light hydrocarbon gases in the hydrocarbon stream 60 and renewable CO2 70 is discharged as a by-product of the process. A fuel gas stream may be recovered as a by-product of this process. The produced hydrogen 28 may be re-used in the process. For example, the hydrogen 28 may be recycled to the hydropyrolysis reactor 14 in the first stage 18. Sufficient hydrogen is produced for use in the entire process disclosed herein. That is, the quantity of the hydrogen 28 produced by the separation, reforming and water-gas shift section 68 is equal to or greater than the hydrogen required to maintain fluidization and sustain chemical consumption of hydrogen in the process.

[0053] The liquid phase product 52 recovered from the gas-liquid separator 50 is fed to a product recovery section 72. In the product recovery section 72, aqueous product 74 is removed from the liquid phase product 52 to generate an intermediate liquid phase product 80. The intermediate liquid phase product 80 may undergo distillation to separate the substantially fully deoxygenated C4+ hydrocarbon liquid into fractions according to ranges of the boiling points of the liquid products contained in the intermediate liquid phase product 80. For example, the substantially fully deoxygenated C4+ hydrocarbon liquid in the intermediate liquid phase product 80 includes naphtha range hydrocarbons, middle distillate range hydrocarbons (e.g., gasoil, diesel) and heavy gasoil (HGO) range hydrocarbons. It is the heavy gasoil (HGO) range hydrocarbons which are used to produce the naphthenic base oil of the present invention (having a final boiling point from 280+ °C). The intermediate liquid phase product 80 comprises about 15 wt.% or less, preferably from 5 wt.% to 15 wt.%, more preferably from 8 wt.% to 12 wt.%, and especially about 10 wt.% of heavy gasoil (HGO) range hydrocarbons, based on the intermediate liquid phase product 80. If the intermediate liquid phase product comprises greater than 15 wt.% of heavy gasoil (HGO) range hydrocarbons, there is a danger that the viscosity of the final renewable naphthenic base oil may be too low for certain lubrication applications. If the intermediate liquid product comprises less than 5 wt.% of heavy gasoil (HGO) range hydrocarbons, there is a danger that the cold flow properties and the yield of the final renewable naphthenic base oil may not be as good as desired.

[0054] For the purpose of clarity, “middle distillates” as used herein are hydrocarbons or oxygenated hydrocarbons recovered by distillation between an atmospheric-equivalent initial boiling point (IBP) and a final boiling point (FBP) measured according to standard ASTM distillation methods. ASTM D86 initial boiling point of middle distillates may vary from between approximately 150 °C to approximately 220 °C. Final boiling point of middle distillates, according to ASTM D86 distillation, may vary from between approximately 280 °C to approximately 310 °C. “Naphtha” as used herein is one or more hydrocarbons or oxygenated hydrocarbons having four or more carbon atoms and having an atmospheric-equivalent final boiling point that is greater than approximately 90 °C but less than approximately 200 °C. A smaller amount of hydrocarbons produced in the process (approximately less than 10 wt.% of total C4+ hydrocarbons, and preferably less than 5 wt.% of total C4+ hydrocarbons) boil at temperatures higher than those for the middle distillates as defined above. That is, these hydrocarbons have a boiling range similar to heavy gasoil produced by distillation of petroleum. Gasoline is predominantly naphtha-range hydrocarbons and is used in spark-ignition internal combustion engines. In the United States, ASTM D4814 standard establishes the requirements of gasoline for ground vehicles with sparkignition internal combustion engines. Gasoil (GO) / diesel is predominantly middle-distillate range hydrocarbons and is used in compression-ignition internal combustion engines. In the United States, ASTM D975 standard covers the requirements of several grades of diesel fuel suitable for various types of diesel engines. ‘Heavy gas oil (HGO) range hydrocarbons’ as used herein are naphthenic rich hydrocarbons. ASTM D86 initial boiling point of heavy gas oil range hydrocarbons may vary preferably from 230 °C to 300 °C, more preferably from 240 °C to 290 °C. ASTM D86 final boiling point of heavy gas oil range hydrocarbons may vary preferably from 400 °C to 480 °C, more preferably from 420 °C to 460 °C. It is this heavy gas oil (HGO) fraction which is used to produce the renewable naphthenic base oil of the present invention.

[0055] Accordingly, in the illustrated embodiment, the intermediate liquid product 80 is fed to a distillation unit 82 to recover gasoline product 84 and a distillate product 86 (e.g., a middle distillate). In certain embodiments, kerosene / jet fuel 88 are recovered as separate streams from the distillation unit 82. The distillate product 86 (e g., the middle distillate) contains kerosene / jet fuel, light and heavy gasoil. It is firstly hydrotreated using a hydrotreatment catalyst (e.g. a CoMo on alumina catalyst) in the hydrotreating reactor 90. This hydrotreating step is carried out at a temperature in the range of from approximately 280 °C to approximately 450 °C and a pressure in the range of from approximately 1 MPa to approximately 6 MPa. As should be noted, pressures higher than 6 MPa may be used to tailor the composition of the resultant hydrocarbon product based on the desired specifications of the hydrocarbon base oil produced by the hydroprocessing. The weight hourly space velocity (WHSV) for this step is in the range of approximately 0.1 h-1to approximately 2 h’1. The hydrotreatment reactor 90 is a fixed bed reactor. However, in certain embodiments, the hydrotreatment reactor 90 may be a fluidized bed reactor.

[0056] The effluent of reactor 90 is subsequently hydroprocessed over an aromatics saturation catalyst (e.g. a Pt on alumina catalyst) in an aromatics saturation reactor 92. This saturation step is carried out at a temperature in the range of from approximately 180 °C to approximately 300 °C and a pressure in the range of from approximately 1 MPa to approximately 6 MPa. As should be noted, pressures higher than 6 MPa may be used to tailor the composition of the resultant hydrocarbon product based on the desired specifications of the hydrocarbon base oil and kerosene / jet fuel produced by the hydroprocessing. The weight hourly space velocity (WHSV) for this step is in the range of approximately 0.05 h'1to approximately 0.5 h'1. The aromatics saturation reactor 92 is a fixed bed reactor. However, in certain embodiments, the aromatics saturation reactor 92 may be a fluidized bed reactor. Finally, the product of reactor 92 is distilled in a fractionation unit 94 into a kerosene / jet fraction top stream 88 and a heavy gasoil bottom stream 96. The aromatics saturation enhances the quality of the kerosine / jet fraction e.g. an increase of its smokepoint. Likewise, if stream 88 would be distilled as a light gasoil (with e.g. a boiling range of 180° C to 280 C) the aromatics saturation would enhance the quality of this diesel fraction e.g. an increase of its cetane number / index.

[0057] In certain embodiments, the oxygen content of the distillate product 86 is less than approximately 1.50 wt.%. For example, the oxygen content may be approximately 1.40 wt.%, 1.25 wt.%, 0.50 wt.%, 0.25 wt.%, or 0.10 wt.% or less. In one embodiment, the sulfur content is less than 100 ppmw. For example, the sulfur content may be approximately 75 ppmw, 50 ppmw, 25 ppmw, 10 ppmw, 5 ppmw, 1 ppmw, or less. Accordingly, the biodiesel obtained from the distillate product 86 is considered an ultra-low sulfur diesel (ULSD), which generally has less than 10 ppmw sulfur. Regarding the nitrogen content, in certain embodiments, the nitrogen content of the substantially fully deoxygenated C4+ hydrocarbon liquid is less than 1000 ppmw. For example, the nitrogen content may be approximately 750 ppmw, 500 ppmw, 250 ppmw, 100 ppmw, 75 ppmw, 50 ppmw, 25 ppmw, 10 ppmw, or 1 ppmw, or less.

[0058] As discussed above, hydrocarbon liquid products such as the distillate product 86 generated from hydroprocessing of solid biomass feedstock (e.g., the solid feedstock 24) generally requires additional processing to upgrade and improve product properties such as cetane number, reduced density, reduced sulfur and / or nitrogen content, reduced benzene content (e.g., as a result of selective saturation), among others, and facilitate tailoring the overall hydrocarbon product to certain location and market specifications, among other benefits.

[0059] BASE OIL COMPOSITIONS AND APPLICATIONS

[0060] The renewable naphthenic base oil of the present invention can be used for the following lubricant / process oil applications, either as a blend component or even up to 100% in some lubricants: print inks, textile oils, leather aid oils, plasticizer for elastomers, thermoplastic elastomers and silicons, carrier oil for additive concentrates, agriculture oils (fertilizer oils, plant protection fluids), adhesives, thermoplastic elastomers, shoe molded parts, road marking, antidust oil, explosives oils, metalworking fluids, cutting and grinding oil, quenching oil, form oil / mould release oils, deform work oil (concrete Mould oil), Refrigerator oils, Heat transfer oils, Shock Absorber Fluids, Calibration Fluids, bearing and circulation oils, transmission oils, hydraulic oils, turbine oils, transformer oils, thermal fluids, dielectric immersion cooling fluids, power steering fluids, greases, pneumatic tool lubricant, engine oils, marine oils, gas engine oils, compressors. In a preferred embodiment herein, the naphthenic base oil component is used as or as a blend component in a transformer oil composition.

[0061] When the renewable naphthenic base oil is used as a blend component for lubricant / process oil compositions, it can be combined with other well-known components of the lubricant / process oil composition in question, e.g. base oils other than the renewable naphthenic base oil described herein, performance additive packages, additive components, and the like. Examples of suitable additive components include antioxidants, anti-corrosion additives, antifoaming agents, detergents, thickeners, anti-wear additives, anti-friction additives, anti-static additives, pour point depressant additives, solvency improvers, and the like. Such additive components are well known to those skilled in the art of formulating lubricant / process oil compositions and further details are not provided herein. When the renewable naphthenic base oil is used in a process oil composition, the level of renewable naphthenic base oil present in the final process oil composition is preferably in the range from 0.1 vol% to 100 vol%, preferably from 1 vol% to 100 vol%, more preferably from 5 vol% to 100 vol%, based on the final process oil composition. When the renewable naphthenic base oil is used in a lubricant composition, the level of renewable naphthenic base oil present in the final lubricant composition is preferably in the range from 0.1 vol% to 99.9 vol%, more preferably from 1 vol% to 99 vol%, even more preferably from 5 vol% to 95 vol%, based on the final lubricant composition. When the renewable naphthenic base oil is used in a transformer oil composition, the level of renewable naphthenic base oil present in the final transformer oil composition is preferably in the range from 0.1 vol% to 99.9 vol%, more preferably from 1 vol% to 99 vol%, even more preferably from 5 vol% to 95 vol%, based on the final transformer oil composition. EXAMPLES

[0062] Example 1 - preparation of renewable naphthenic base oil

[0063] A renewable naphthenic base oil component was prepared from the distillate fraction resulting from hydropyrolysis and hydroconversion of pinewood chips according to a process similar to the process discussed above with reference to FIG. 1. The second stage total liquid product (80 in FIG.l) was distilled into a <135°C fraction (the gasoline product (84) in FIG. 1) and a >135°C fraction (the distillate product (86) in FIG. 1). The >135°C fraction was subjected to hydrotreatment and aromatic saturation process using the following process conditions:

[0064] Conditions for Hydrotreatment: CoMo catalyst, 30 bar, 1 h'1, 340°C

[0065] Conditions for Aromatic Saturation: Pt based catalyst, 33 bar, 0.2 h’1, 220°C

[0066] Subsequently the final aromatic saturation product was distilled into a kerosene / jet fuel fraction (<280°C) and a naphthenic base oil fraction (>280°C). It is the naphthenic base oil fraction which is used as Example 1. The properties of the naphthenic base oil are set out in Table 1 below. By way of comparison, Table 1 also sets out the properties of Ergon HYGOLD® 60, a naphthenic crude-derived light base oil commercially available from Ergon (Comparative Example 2). Further, Table 1 includes the properties of a base oil prepared according to Example 4 in US7888542 (Table 3) (Comparative Example 1 in Table 1 below).

[0067] TABLE 1

[0068] * Base Oil prepared according to Example 4 in Neste patent US7888542 (Table 3)

[0069] **Ergon HYGOLD® 60

[0070] ***Measured according to ASTM D 2549

[0071] NK = Not Known

[0072] The data in Table 1 show that the renewable naphthenic base oil of the present invention (Example 1) contains less i-paraffinic molecules and even more naphthenic molecules than a typical crude-derived naphthenic base oil (Comparative Example 2). Hence the renewable naphthenic base oil of Example 1 may replace the crude-derived naphthenic base oil of Comparative Example 2. By this replacement, the carbon footprint of the naphthenic base oil can be reduced, and its production is not dependent on relatively scarce naphthenic crude.

[0073] Furthermore, the evaporation loss at elevated temperatures was lower for the renewable naphthenic base oil of Example 1 as compared to that of the HYGOLD® 60 base oil of Comparative Example 2. The lower evaporation loss was surprising because the viscosity of Example 1 was less than Comparative Example 2, suggesting that Example 1 has smaller molecules that are expected to evaporate more easily.

[0074] A lower evaporation loss is seen to be a good indicator of a better fuel performance. In addition, a lower evaporation loss is also beneficial for process oils. For example, elastomers produced with the process oils have less fogging with a lower evaporation loss.

[0075] The aniline point results show that the HYGOLD® 60 base oil has a lower aniline point indicating a slightly higher naphthenic plus aromatic amount / polarity than the renewable naphthenic base oil of Example 1. However, the carbon distribution measured with ASTM D2140 would have suggested the opposite - namely that the renewable naphthenic base oil of Example 1 having the reported naphthenic and aromatic content should result in a lower aniline point and higher evaporation loss than the HYGOLD® 60 base oil.

[0076] Without being bound by theory, a possible explanation for the surprising higher aniline point and lower evaporation loss for the renewable naphthenic base oil of Example 1 is the higher polynaphthenic content resulting in a higher boiling point of the renewable naphthenic base oil. In addition, or in the alternative, an explanation for the surprising results may be that polar forces are lower in higher ring structures.

[0077] The data in Table 1 also indicate that the renewable naphthenic base oil of the present invention (Example 1) is considerably lighter and less viscous than a renewable naphthenic base oil described in US7888542 (Comparative Example 1).

[0078] Moreover, the data in Table 1 illustrate that the renewable naphthenic base oil of the present invention (Example 1) has a higher naphthenes content and a higher polynaphthenes content than a renewable naphthenic base oil described in US7888542B2. Consequently, the solvency power of the naphthenic base oil of Example 1 will be higher than that of Comparative Example 1. The data in Table 1 also indicate that the light renewable naphthenic base oil of the present invention (Example 1) has a 398° C minus content of more than 97 wt.% whilst the heavy renewable naphthenic base oil described in US7888542 (Comparative Example 1) has a 398° C plus content of 95 wt.%. The heaviness of the renewable base oil in Comparative Example 1 can be attributed to its production by oligomerization creating large molecules which are predominantly in the C34-C36 range (see Figure 2 of US7888542B2). Therefore, the naphthenic base oil of Example 1 can be characterized as a very naphthenic light base oil combined with a low aromatic content. For this reason, the naphthenic base oil of Example 1 is very suitable for the following lubricant / process oil applications, either as a blend component or even up to 100% in some lubricants: print inks, textile oils, leather aid oils, plasticizer for elastomers, thermoplastic elastomers and silicons, carrier oil for additive concentrates, agriculture oils (fertilizer oils, plant protection fluids), adhesives, thermoplastic elastomers, shoe molded parts, road marking, anti dust oil, explosives oils, metalworking fluids, cutting and grinding oil, quenching oil, form oil / mould release oils, deform work oil (concrete mould oil), refrigerator oils, heat transfer oils, shock absorber fluids, calibration fluids, bearing and circulation oils, transmission oils, hydraulic oils, turbine oils, transformer oils, thermal fluids, dielectric immersion cooling fluids, power steering fluids, greases, pneumatic tool lubricant, engine oils, marine oils, gas engine oils, and compressors.

[0079] Examples 2 and 3

[0080] Two transformer oil compositions were formulated using the naphthenic base oil of Example 1. The transformer oil composition of Example 2 contained 99.7 wt.% of the naphthenic base oil of Example 1 and 0.3 wt.% Butylated Hydroxy Toluene (BHT) antioxidant additive. Example 3 contained 90 wt.% of the naphthenic base oil of Example 1, 9.7 wt.% of Shell RISELLA® X 415 (a GTL-based oil commercially available from Shell having a kinematic viscosity at 100°C of 2.7 mm2 / s) and 0.3 wt.% of Butylated Hydroxy Toluene (BHT) antioxidant additive. The transformer oil compositions were subjected to oxidation tests which are key tests to predict the lifetime and stability of the compositions. The transformer oils DIALA™ S2 ZX A and DIALA™BX, commercially available from Shell, were used as comparative examples. The results of these experiments are set out in Table 2 below. TABLE 2

[0081] The features of the naphthenic base oil of Example 1 can be used as transformer fluids according to IEC 60296 and ATSM D 3487, the most common industry specs for transformer liquids based on hydrocarbons. The results in Table 2 show that the naphthenic base oil of Example 1 can be used successfully in a transformer fluid formulation. Example 2 has been shown to meet the ASTM D 3487 specification and Example 3 has been shown to meet both the ASTM D3487 and the IEC 60296 (Type A, high grade) specifications.

[0082] Despite the high oxygen content of the starting material of Example 1 relative to that of naphthenic crude (oxygen content of wood is typically 43 wt.% compared to an oxygen content of typically 0.3 wt.% for naphthenic crude), the final renewable naphthenic base oil of Example 1 is of high purity and has a very high oxidative stability. This is unexpected in view of the fact that wood consists of high quantities of water and dry wood typically consists of 50 wt.% carbon, 43 wt.% oxygen, 6 wt.% hydrogen and 1 wt.% nitrogen and others, while naphthenic crude oil typically consists of 83-87 wt.% carbon, 10 to!4 wt.% hydrogen, 0.1 to 2 wt.% nitrogen, 0.1-1.5 wt.% oxygen, 0.5 to 6 wt.%sulfur, <0.1 wt.% metals. The renewable naphthenic base oil of Example 1 contains <0.06 wt.% oxygen, <2.5 ppmw sulfur and <2.5 ppmw nitrogen, and therefore we are still achieving the same quality as a naphthenic base oil derived from naphthenic crude oil, but with a reduced carbon footprint.

Claims

CLAIMS1. A renewable naphthenic base oil comprising a mixture of mononaphthenic compounds and polynaphthenic compounds, wherein the amount of mononaphthenic compounds is below 20 wt.%, based on the renewable naphthenic base oil, and wherein the amount of polynaphthenic compounds is greater than 50 wt.%, based on the renewable naphthenic base oil, and wherein at least 85 wt.% of the renewable naphthenic base oil has a boiling point greater than 280°C.

2. A renewable naphthenic base oil according to Claim 1, wherein the renewable naphthenic base oil has a dynamic viscosity at 40°C of greater than 4.5 mm2 / s3. A renewable naphthenic base oil according to Claim 1 or 2, wherein the renewable naphthenic base oil has a dynamic viscosity at 40°C of less than 12 mm2 / s.

4. A renewable naphthenic base oil according to any of Claims 1 to 3, wherein the renewable naphthenic base oil has a carbon distribution in which at least 50% are naphthenic carbons.

5. A renewable naphthenic base oil according to any of Claims 1 to 4, wherein the renewable base oil has an initial boiling point of greater than 230° C.

6. A renewable naphthenic base oil according to any of Claims 1 to 5, wherein the renewable naphthenic base oil has a final boiling point below 500° C.

7. A renewable naphthenic base oil according to any of Claims 1 to 6, wherein the renewable naphthenic base oil has a density at 15° C between 860 and 895 kg / m3.

8. A renewable naphthenic base oil according to any of Claims 1 to 7, wherein the renewable naphthenic base oil has a carbon distribution such that the sum of Ca + Cn (where Ca is the amount of carbon atoms in aromatic rings and Cn is the amount of carbon atoms in naphthenic rings) is in the range from 55% to 65%, preferably from 56% to 60% (as measured according to ASTM D2140).

9. A renewable naphthenic base oil according to any of Claims 1 to 8, wherein the amount of mononaphthenic compounds is in the range of 3 wt.% to 12 wt.%, preferably from 4 wt.% to 10 wt.%, based on the renewable naphthenic base oil.

10. A renewable naphthenic base oil according to any of Claims 1 to 9 wherein the amount of polynaphthenic compounds is in the range from 52 wt.% to 90 wt.%, preferably in the range from 60 wt.% to 85 wt.%, based on the renewable naphthenic base oil.

11. A renewable naphthenic base oil according to any of Claims 1 to 10 wherein the polynaphthenic compounds comprise a mixture of dinaphthenic compounds and trinaphthenic plus compounds, wherein the amount of dinaphthenic compounds is 20 wt.% or greater and the amount of trinaphthenic plus compounds is 25 wt.% or greater, based on the renewable naphthenic base oil.

12. A renewable naphthenic base oil according to any of Claims 1 to 11 wherein at least 95 wt.% of the renewable naphthenic base oil has a boiling point greater than 280°C.

13. A renewable naphthenic base oil according to any of Claims 1 to 12 wherein the renewable naphthenic base oil is generated from hydropyrolysis and hydroconversion of a solid biomass containing lignocellulose.

14. A renewable naphthenic base oil according to any of Claims 1 to 13, wherein the renewable naphthenic base oil is generated by a hydroprocess comprising: hydropyrolysing a solid feedstock in the first stage hydropyrolysis reactor to generate a product stream comprising partially deoxygenated hydropyrolysis product, H2O, H2, CO2, CO, Ci - C3 gases, char and catalyst fines; feeding at least a portion of the product stream to a second stage hydroconversion reactor comprising one or more hydroconversion catalysts; and hydroconverting the partially deoxygenated hydropyrolysis product in the product stream to generate a vapor phase product comprising substantially fully deoxygenated hydrocarbon product, H2O, CO, CO2, and Ci - C3 gases; condensing the vapor phase product to generate a deoxygenated hydrocarbon liquid comprising the substantially fully deoxygenated hydrocarbon product, fractionating the substantially fully deoxygenated hydrocarbon product into a gasoline product and a distillate product;subjecting the distillate product to hydrotreatment and aromatic saturation steps to produce a naphthene rich stream; fractioning the naphthene rich stream into a kerosene fuel fraction and a renewable naphthenic base oil.

15. A process for producing a renewable naphthenic base oil comprising: feeding a solid feedstock and hydrogen to a first stage hydropyrolysis reactor, wherein the first stage hydropyrolysis reactor comprises one or more deoxygenation catalysts, and wherein the solid feedstock comprises biomass containing lignocellulose; hydropyrolysing the solid feedstock in the first stage hydropyrolysis reactor to generate a product stream comprising partially deoxygenated hydropyrolysis product, H2O, H2, CO2, CO, Ci - C3 gases, char and catalyst fines; feeding at least a portion of the product stream to a second stage hydroconversion reactor comprising one or more hydroconversion catalysts; hydroconverting the partially deoxygenated hydropyrolysis product in the product stream to generate a vapor phase product comprising substantially fully deoxygenated hydrocarbon product, H2O, CO, CO2, and Ci - C3 gases; condensing the vapor phase product to generate a deoxygenated hydrocarbon liquid comprising the substantially fully deoxygenated hydrocarbon product, fractionating the substantially fully deoxygenated hydrocarbon product into a gasoline product and a distillate product; subjecting the distillate product to hydrotreatment and aromatic saturation steps to produce a naphthene-rich stream; and fractioning the naphthene-rich stream into a kerosene fuel fraction and a renewable naphthenic base oil.

16. A transformer oil composition comprising the renewable naphthenic base oil according to any of Claims 1 to 13, or the renewable naphthenic base oil produced by the process of Claim 14 or 15.

17. A process oil composition comprising the renewable naphthenic base oil according to any of Claims 1 to 13, or the renewable naphthenic base oil produced by the process of Claim 14 or 15.

18. A lubricant composition comprising the renewable naphthenic base oil according to any of Claims 1 to 13, or the renewable naphthenic base oil produced by the process of Claim 14 or 15.

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