Method for producing rosinol

Abstract

The present disclosure relates to a process for producing rosinol from renewable materials comprising abietic acid, such as raw materials comprising crude tall oil. According to the method, abietic acid present in the renewable material is separated (101) and a stream comprising at least partially separated abietic acid is subjected to a thermal decarboxylation reaction (102) to produce a stream comprising formed rosin oil and rosin oil is recovered (103) from the stream. The present disclosure also relates to a system for carrying out the method, and the use of rosinol obtainable by the method as a renewable feedstock co-processed with fossil feedstock to increase the renewable content of fossil transport fuels and / or chemicals, and the use of co-processing with other renewable feedstocks to produce renewable fuels and / or chemicals or components thereof. The present disclosure also relates to a rosin oil product obtainable by the process.

Description

Technical Field

[0001] This disclosure relates to a method for producing rosin oil from a renewable material containing abietic acid, such as crude tall oil. The method includes thermally decarboxylating the abietic acid to produce a stream containing rosin oil, and separating the rosin oil from the stream. This disclosure also relates to systems and apparatus for carrying out this method, uses of the rosin oil obtained by this method, and the rosin oil product obtained by this method. Background Technology

[0002] Rosin is a naturally occurring solid resinous substance found in pine trees. There are three main sources of rosin: resinous rosin extruded from the oil of living pine trees; wood rosin derived from the oleoresin contained in old tree stumps; and tall oil rosin, a waste product recycled as a byproduct of the kraft paper industry. Rosin is a component of printing inks, copy paper and laser printing paper, varnishes, adhesives, soaps, paper sizing agents, baking soda, fluxes, and sealing waxes.

[0003] Rosin mainly contains abietic acid. Abietic acid is a tricyclic diterpenoid compound containing two chemically reactive centers: a double bond and a carboxyl group.

[0004] Rosin acid can be decarboxylated through thermal or oxidative reactions. Decarboxylation is generally considered an undesirable side reaction.

[0005] EP0149958 discloses a method for accelerating the decarboxylation of rosin acid by carrying out a decarboxylation reaction in the presence of one or more accelerators, such as high-sulfur tall oil rosin, fatty acids, and organic and inorganic sulfides. The resulting hot oil can be used in rubber formulation.

[0006] EP3838998 discloses a hydrocarbon composition derived from biorenewable rosin and its uses.

[0007] Sundqvist et al. (Can. J. Chem. Engineering, 77, 1999, pp. 465-472) have found that decarboxylation helps to increase the concentration of resin salts in the reaction of resin salt calcium because it can control the increase in solution viscosity to the desired level, thus making resin salts usable as ink carriers.

[0008] Bernas et al. (Top Catal, 2012, 55, pp. 673-679; DOI 10.1007 / s11244-012-9846-7) disclosed a method for producing aliphatic hydrocarbons from tall oil rosin. Furthermore, they suggested using the resulting aliphatic hydrocarbons as fuel additives.

[0009] Bio-derived raw materials, such as byproducts of the kraft paper industry, are also potential sources of various renewable fuels and renewable fuel components, as well as renewable chemicals. These raw materials can be converted into renewable fuels by guiding them into a catalytic reactor and simultaneously contacting them with gaseous hydrogen. The resulting products can be further refined and ultimately fractionated into the desired renewable fuels, renewable fuel components, and / or renewable chemicals.

[0010] However, the quality of renewable feedstocks is not always at the level required for the catalytic steps to function most effectively. Highly acidic renewable feedstocks, such as those derived from crude tall oil, can cause serious corrosion problems. Furthermore, low feedstock impurity levels are desirable for both co-processing and regenerative production, especially when co-processing renewable feedstocks in fossil refineries. Additionally, it is necessary to refine low-value by-products (such as crude tall oil (CTO) fractionation by-products) into high-value products. Sometimes market fluctuations can create bottlenecks; therefore, it is advantageous or necessary to flexibly utilize by-products such as rosin acid for refining the final product. Summary of the Invention

[0011] One aspect of this disclosure is to provide a specific method for producing rosin oil, the method comprising the following steps: a) Provide renewable materials containing rosin acid; b) Separate at least a portion of rosin acid from renewable materials; c) subjecting a stream containing at least partially separated rosin acid to a thermal decarboxylation reaction at a temperature greater than 280°C to 360°C for a time sufficient to provide a conversion of at least 90% of the rosin acid to form rosin oil, and continuously removing the stream containing the formed rosin oil from the thermal decarboxylation; and d) The rosin oil formed by recycling.

[0012] According to another aspect, this disclosure relates to the use of rosin oil obtained from the method according to claim 1 as a renewable feedstock co-processed with fossil feedstocks to increase the renewable content of fossil transport fuels and / or fossil chemicals.

[0013] According to another aspect, this disclosure relates to the use of rosin oil obtainable by the method of claim 1, co-processed with other renewable raw materials to produce renewable fuels and / or renewable chemicals, or components thereof.

[0014] According to another aspect, this disclosure relates to a system for carrying out a method of producing rosin oil from a renewable feedstock comprising crude tall oil, the system comprising

[0015] - Dewatering equipment configured to remove at least water from the raw material; - Deasphalting equipment configured to separate tall oil bitumen from dehydrated feedstock to produce a fraction containing tall oil bitumen and a fraction containing deasphalted tall oil. - A separation unit configured to separate deasphalted tall oil into Defatty acid stream containing rosin acid and Flow containing fatty acids; - A decarboxylation reactor configured to decarboxylate a decarboxylation stream containing rosin acid to obtain a stream containing the formed rosin oil; and - A separation apparatus configured to separate rosin oil from a stream containing formed rosin oil to obtain a stream of rosin oil and a stream of derosin oil; and - A recycling unit configured to return at least a portion of the decarboxylated rosin oil stream to the decarboxylation reactor.

[0016] According to another aspect, this disclosure relates to an apparatus comprising:

[0017] - A continuous flow reactor configured to thermally decarboxylate a stream containing rosin acid and obtain a stream containing the formed rosin oil; - A separation device configured to separate at least rosin oil from a stream containing formed rosin oil to obtain a recovered rosin oil and a derosin oil stream; and - A circulation device configured to return at least a portion of the stripped rosin oil stream to a continuous flow reactor.

[0018] According to another aspect, this disclosure relates to a rosin oil product comprising: The rosin oil content is greater than 85 wt%, preferably greater than 90 wt%, more preferably greater than 95 wt%, and most preferably greater than 97 wt%. 0.1-10 wt%, preferably 0.1-5 wt%, more preferably 0.1-2 wt%, and most preferably 0.5-2 wt% of rosin acid; Other neutral components, ranging from 0.1% to 5 wt% (e.g., 0.1% to 5 wt%). 0-5wt% (e.g., 0.1-5wt%) of light acid; and 0-3wt% (e.g., 0.1-3wt%) of heavy (C20+) compounds.

[0019] The appended dependent claims describe several exemplary and non-limiting embodiments of the invention.

[0020] When the feed used in the decarboxylation unit is largely or entirely obtained through CTO evaporation, the metal content of the rosin oil is advantageously lower. Furthermore, the rosin oil obtained by this method mixes well with fossil feedstocks, etc. The method disclosed herein can create additional value for the by-stream of CTO separation. The separation process can be further optimized to increase the low-grade rosin acid stream while producing better rosin products. When this method is combined with a CTO separation unit, the rosin is already heated, thus saving energy in the processing.

[0021] Furthermore, this method can be converted from producing arosin acid to producing rosin oil. Rosin oil can then be stored at lower temperatures, thus providing logistical flexibility.

[0022] Reading the following description of specific exemplary and non-limiting embodiments in conjunction with the accompanying drawings will help to better understand the various exemplary and non-limiting embodiments of the present invention and their additional objects and advantages.

[0023] The verbs “comprising” and “including” are used herein as open-ended restrictions, neither excluding nor requiring the presence of any unlisted features. Unless otherwise expressly stated, the features listed in the dependent claims may be freely combined with each other. Furthermore, it should be understood that the use of “a” or “an” herein, i.e., the singular form, does not exclude the plural. Attached Figure Description

[0024] Figure 1 An exemplary non-limiting schematic diagram of rosin oil production according to one embodiment of the present disclosure is shown.

[0025] Figure 2 An exemplary system for producing rosin oil from a feedstock containing crude tall oil is shown.

[0026] Figure 3 An apparatus 300, representing an exemplary non-limiting embodiment of the present disclosure, is shown, comprising a continuous flow reactor 301 configured to thermally decarboxylate a stream A containing rosin acid and obtain a stream B containing the formed rosin oil. l， g Separation device 302, which includes an evaporator 303 and a condenser 304, for recovering rosin oil; and circulation device 305, for returning at least partially de-rosin oiled stream D to the reactor.

[0027] Figure 4 An apparatus 400, representing an exemplary non-limiting embodiment of the present disclosure, is shown, comprising a continuous flow reactor 401 configured to thermally decarboxylate a stream A containing rosin acid and obtain a stream B containing the formed rosin oil. l， gSeparation device 402, comprising evaporator 403 and distillation column 404, for separating stream B ( l，g The reactor comprises a stream D separated into rosin oil and derosin oil; a recovery unit 406 for separating rosin acid E from the derosin oil stream; and a circulation unit 405 for returning at least a portion of the derosin oil stream and / or the recovered rosin to the reactor. The reactor and distillation column are configured to operate at the same pressure.

[0028] Figure 5 An apparatus 500, representing an exemplary non-limiting embodiment of the present disclosure, is shown, comprising a continuous flow reactor 501 for converting a stream A containing rosin acid into a stream B containing rosin oil. l，g The separation unit 502 includes an evaporator 503 and a distillation column 504 for separating stream B into rosin oil and a derosin oil stream D; a recovery unit 506 for separating rosin acid E from the derosin oil stream; and a circulation unit 505 for returning at least a portion of the derosin oil stream and / or the recovered rosin acid to the reactor. The reactor and distillation column are configured to operate at different pressures.

[0029] Figure 6 An apparatus 600, representing an exemplary non-limiting embodiment of the present disclosure, is shown, comprising a continuous flow reactor 601 for converting a stream A containing rosin acid into a stream B containing rosin oil. l，g Separation device 602, comprising evaporator 603, condenser 610 and distillation column 604, for separating stream B ( l，g The reactor comprises a stream D separated into rosin oil and derosin oil; a recovery unit 606 for separating rosin acid E from the derosin oil stream; and a circulation unit 605 for returning at least a portion of the derosin oil stream and / or the recovered rosin to the reactor. The reactor and distillation column are configured to operate at the same pressure.

[0030] Figure 7 An apparatus 700, illustrating an exemplary non-limiting embodiment of the present disclosure, includes a continuous flow reactor 701 for converting a stream A containing rosin acid into a stream B containing rosin oil. l，g Separation device 702, comprising evaporator 703 and distillation column 704, for separating stream B ( l，g The reactor comprises a stream D separated into rosin oil and derosinized oil; a recovery unit 706 for separating rosin acid E from the derosinized oil stream; and a circulation unit 705 for returning at least a portion of the derosinized oil stream and / or the recovered rosin to the reactor. The reactor and distillation column are configured to operate at the same pressure.

[0031] Figure 8An apparatus 800, representing an exemplary non-limiting embodiment of the present disclosure, is shown, comprising a continuous flow reactor 801 for converting a stream A containing rosin acid into a stream B containing rosin oil. l，g ); Separation device 802, which includes an evaporator 803 integrated into the reactor and a distillation column 804, for separating stream B ( l，g The reactor is configured to separate a stream of rosin oil and a stream of derosin oil into a stream D; a recovery unit 806 for separating rosin acid E from the stream of derosin oil; and a recycling unit 805 for returning at least a portion of the stream of derosin oil and / or the recovered rosin to the reactor.

[0032] Figure 9 Exemplary evaporator structures 907a and 907b are shown for feeding stripping gases such as carbon dioxide into the evaporator. Figure 4-8 The device. Detailed Implementation

[0033] Figure 1 An exemplary method for producing rosin oil according to this disclosure is shown. Reference numerals and arrows in the figure represent reactions and flows, respectively.

[0034] Therefore, the method includes the following steps: a) Provide renewable material A containing rosin acid; b) Separate at least a portion of 101 rosin acid from renewable materials; c) subjecting a stream containing at least partially separated rosin acid to a thermal decarboxylation reaction at a temperature greater than 280°C to 360°C for a time sufficient to provide a conversion of at least 90% of the rosin acid to form rosin oil, and continuously removing the stream containing the formed rosin oil from the thermal decarboxylation reaction; and d) Recover the rosin oil formed from 103.

[0035] Abietic acid is a tricyclic diterpenoid compound in which a carboxylic acid group is contained on the 4th tertiary carbon of ring A. Exemplary abietic acids suitable for use in this disclosure are abietic acid (CAS No. 514-10-3), isopyric acid (CAS No. 5835-26-7), L-opyric acid (CAS No. 79-54-9), neoabietic acid (CAS No. 471-77-2), longleaf abietic acid (CAS No. 1945-53-5), piratic acid (CAS No. 127-27-5), santalinic acid (CAS No. 471-74-9), dehydroabietic acid (1740-19-8), and mixtures thereof.

[0036] Abietic acid undergoes decarboxylation at high temperatures to produce rosin oil. This means that the abietic acid molecule loses its acidic groups and releases carbon dioxide, thus degrading into the lighter, neutral rosin oil. Therefore, rosin oil is a product of the decarboxylation reaction of abietic acid. As an illustrative example, the decarboxylation of abietic acid is shown below.

[0037]

[0038] The renewability of carbon-containing compositions (such as raw materials and bio-based products, i.e., renewable materials) can be compared with that of raw materials. 14 C isotope content and atmospheric values ​​in 1950 14 The content of C isotopes is used to determine this. 14 Carbon isotope content can serve as evidence of the renewable source of raw materials or products. Compared to carbon atoms from fossil sources, carbon atoms in renewable materials contain more unstable radioactive carbon (C). 14 C) Atoms. Therefore, through analysis 12 C and 14 The ratio of carbon isotopes can distinguish between carbon compounds derived from biological sources and those derived from fossil sources. Therefore, specific isotopic ratios can be used to identify and quantify renewable carbon compounds, differentiating them from non-renewable carbon compounds (i.e., fossil carbon compounds). The isotopic ratio does not change during chemical reactions. A suitable method for analyzing the content of carbon from biological sources is ASTM D6866 (2020). An article by Dijs et al. (Dijs et al., Radiocarbon, 48(3), 2006, pp 315-323) provides an example of how ASTM D6866 can be applied to determine the content of renewable components in fuels. For the purposes of this invention, a carbon-containing material (such as a raw material or product) is considered to be of renewable origin if it contains 90% or more modern carbon (e.g., 100% modern carbon) as measured according to ASTM D6866.

[0039] The renewable materials disclosed herein typically contain at least 20 wt% abietic acid, preferably at least 90 wt% abietic acid. In addition to abietic acid, the renewable materials may also include other renewable components such as fatty acids, aldehydes, ketones, alcohols, terpenes, ethers and / or sterols.

[0040] Exemplary renewable materials suitable for this method include crude tall oil, tall oil, tall oil pitch, deasphalted tall oil, distilled tall oil (DTO), and tall oil rosin, all of which contain rosin acid. Additionally, other renewable materials containing rosin acid, such as resins, can also be used.

[0041] In one exemplary embodiment, the renewable material comprises crude tall oil. The CTO content in the renewable material is preferably at least 10 wt% CTO, more preferably at least 50 wt% CTO, and even more preferably at least 90 wt% CTO.

[0042] In one embodiment, the sulfur content in the renewable material is less than 300 ppm by weight, more preferably less than 150 ppm, most preferably less than 130 ppm, such as less than 100 ppm, less than 80 ppm, or even less than 50 ppm. A low sulfur content is preferred when the product of this method (i.e., rosin oil) is co-treated with oxygen-containing renewable materials.

[0043] In a particular embodiment, the renewable material used for the decarboxylation reaction is rosin acid derived from CTO. In this embodiment, the method includes the following steps prior to the thermal decarboxylation reaction: i) Dehydrate renewable materials to produce dehydrated renewable materials; ii) Deasphalting dehydrated renewable materials to produce The fraction containing tall oil asphalt, and Fractions containing deasphalted tall oil; and iii) Separating the fraction containing deasphalted tall oil to produce Streams containing fatty acids, and Defatty acid stream containing isolated rosin acid.

[0044] The dehydration step removes substances such as water and turpentine from renewable materials. Dehydration is typically carried out under a moderate vacuum between 120 and 200°C. Exemplary dehydration conditions involve rapid heating to 200°C under reduced pressure (e.g., at 5 kPa). The dehydrated renewable materials contain fatty acids (such as TOFA), rosin acids, and tall oil pitch.

[0045] Deasphalting is typically performed on dehydrated renewable materials to separate asphalt compounds from the material. Exemplary deasphalting conditions include a temperature of approximately 300°C and a pressure of approximately 1 kPa. Shorter deasphalting times, such as a few seconds, for example 1-5 seconds, are preferred to avoid premature decarboxylation of rosin acids present in the dehydrated renewable materials.

[0046] The deasphalted renewable material contains fatty acids and rosin acid, which are separated by means of distillation, for example, before thermal decarboxylation of the rosin acid.

[0047] The dehydration and deasphalting of CTO are disclosed in more detail in, for example, L.-H. Norlin’s Encyclopaedia of Industrial Chemistry, 2005, Chapter Tall Oil, pp. 1-14, which is incorporated herein by reference.

[0048] According to this method, most of the fatty acids are separated from renewable materials before the thermal decarboxylation reaction to produce...

[0049] fatty acid-containing streams and

[0050] Defatty acid stream containing rosin acid.

[0051] Defatty acid streams containing rosin acid are used to produce rosin oil.

[0052] The defatty acid stream typically contains less than 40 wt%, preferably less than 10 wt%, more preferably less than 5 wt%, and most preferably less than 1 wt% of fatty acids.

[0053] In one embodiment, the decarboxylic acid stream contains tall oil pitch and rosin acid. The decarboxylic acid stream containing tall oil pitch and rosin acid can undergo a thermal decarboxylation reaction. The decarboxylation reaction conditions are as follows.

[0054] The fatty acid-containing stream may still contain rosin acid that can be used in this method. Therefore, it is preferable to utilize the remaining rosin acid in this method as well.

[0055] Therefore, in a preferred embodiment, the fatty acid-containing stream is distilled to produce...

[0056] a. Fractions containing fatty acids, and

[0057] b. One or more fractions containing rosin acid.

[0058] One or more fractions containing rosin acid can be decarboxylated to increase the overall yield of rosin oil. The decarboxylation reaction conditions are described below.

[0059] In another embodiment, prior to decarboxylation, the decarboxylated fatty acid stream containing at least a portion of rosin acid is separated into at least one of the following fractions: a. The first rosin acid fraction, which is in a gaseous state under processing conditions, such as a temperature of 150°C or higher, preferably 150°C to 250°C, such as 150°C to 200°C, and a pressure of approximately 2 kPa. b. The second rosin acid fraction, which is liquid under processing conditions; and c. The third rosin acid fraction, which is solid under processing conditions. The condition is that the first rosin acid fraction is condensed before the thermal decarboxylation reaction. According to this embodiment, at least one fraction, preferably two fractions, and more preferably the first and second rosin acid fractions, are decarboxylated. The decarboxylation reaction conditions are as follows.

[0060] In one embodiment, the decarboxylation method includes subjecting at least part, preferably all, of the decarboxylated fatty acid stream to a thermal decarboxylation reaction.

[0061] Decarboxylation is carried out at temperatures above 280°C to 360°C for a time sufficient to provide a conversion of at least 90%, preferably at least 95%, of rosin acid to rosin oil. The reaction time, i.e., the time the material spends in the decarboxylation reactor to produce at least 90% conversion, is typically 3–12 hours, such as 8–12 hours. The term "conversion" herein refers to the total conversion of rosin acid in the decarboxylation reaction. The conversion depends on several parameters, such as reactor size, reaction time, temperature, etc. Depending on the size of the reactor setup, the single-pass conversion in the reactor can be adjusted to be relatively low, such as 30–50%. The conversion, i.e., the total conversion, can be improved by effectively recovering reactants such as rosin acid. Preferably, different streams, particularly the stream of decarboxylated rosin oil formed, are circulated to the reheat decarboxylation reaction and rosin oil separation unit to improve the conversion of rosin acid and increase the yield of rosin oil. Furthermore, the residence time of the reactants can be adjusted by changing the mass hourly space velocity (WHSV) of the rosin acid feed into the decarboxylation reactor.

[0062] The pressure for decarboxylation reactions is typically 0.1-110 kPa.

[0063] In one embodiment, the decarboxylation reaction is carried out at a low pressure, ranging from 0.1 to less than 20 kPa, such as 0.5 to less than 20 kPa. Therefore, the pressure can be 0.1, 0.5, 1, 2, 3, 4, 5, 7, 9, 10, 12, 15, or 17 kPa, up to as high as 7, 9, 10, 12, 15, 17, 18.5, 19, or less than 20 kPa.

[0064] Using low pressure helps the evaporation of rosin oil, which in turn helps remove rosin oil from the decarboxylation reaction.

[0065] In one embodiment, the decarboxylation reaction is carried out under high pressure, ranging from 20 to 110 kPa. Therefore, the pressure can be 20, 30, 40, 50, 60 or 70 kPa, up to 40, 50, 60, 70, 80, 90, 100, 110 kPa.

[0066] Depending on the required production capacity, decarboxylation reactors can be quite large vessels. The risk of corrosion may necessitate the use of high-grade stainless steel materials, especially for low-pressure equipment requiring vacuum resistance, which may necessitate thick walls, thus increasing the economic burden.

[0067] One advantage of atmospheric operation is the simplicity of handling the CO2 purge stream, since CO2 is produced in the decarboxylation reaction and must be continuously discharged from the reactor. The CO2 purge stream carries away volatile organic compounds (VOCs). Under reduced pressure operation, more organic matter is carried away from the reactor by CO2 than under atmospheric pressure. In both cases, the organic matter can be recovered to improve production yield and reduce potential environmental impact.

[0068] When operating under high or near-atmospheric pressure conditions, the recovery of high-boiling-point organic compounds from CO2 is more comprehensive and results in less loss than under low-pressure conditions. Furthermore, the smaller, basic condenser design allows for operation at higher pressures, thus saving on equipment costs.

[0069] When the decarboxylation reaction is carried out under the above conditions, the decarboxylation of rosin acid does not require a decarboxylation catalyst. Therefore, no decarboxylation catalyst is added in the decarboxylation reaction. However, feedstocks containing CTO may include components that can be catalytically decarboxylated, such as sulfur-containing compounds. When the term "decarboxylation" is used, it refers to a reduction in the number of compounds containing carboxyl groups, and does not necessarily mean that all carboxyl groups are removed. Preferably, at least 95% of the carboxyl groups of rosin acid in the feed are removed in the decarboxylation step.

[0070] The stream containing the formed rosin oil may still contain materials with boiling points higher and / or lower than rosin oil, such as non-condensables and high-boiling residues (which contain neutral components such as sitosterol and its esters), residual rosin acids, and acids heavier than rosin acids (such as C(20+) fatty acids). The amount of materials other than rosin oil depends on the decarboxylation reaction conditions and the mass of the rosin acid-containing stream fed into the decarboxylation reaction.

[0071] In one implementation, the method further includes steps after step c) and before step d): i. Separating the formed rosin oil and the derosin oil from a stream containing the formed rosin oil; and ii. Recycle at least a portion of the derosin oil stream to the thermal decarboxylation reaction in step c).

[0072] Depending on the conditions of the decarboxylation reaction, the stream containing the rosin oil may contain a liquid phase and / or a gas phase.

[0073] In one embodiment, the stream containing the formed rosin oil contains a liquid phase and a gas phase, and the method includes separating the formed rosin oil from at least one of the phases.

[0074] In one embodiment, separating the formed rosin oil from the liquid phase includes: a. The liquid phase is directed to a first evaporator operating at 260°C or above (preferably 300°C or above) to produce a stream containing rosin oil vapor and a stream de-rosin oil; and b. Distilling and / or condensing the rosin oil-containing stream to provide purified rosin oil.

[0075] In one embodiment, separating the formed rosin oil from the gas phase includes condensing and / or distilling the rosin oil with the gas phase to provide purified rosin oil.

[0076] In one embodiment, the method includes directing a non-condensable gas (such as carbon dioxide, steam, or nitrogen) to the separation process of step i to enhance the stripping effect. Preferably, the carbon dioxide is carbon dioxide formed during the decarboxylation reaction.

[0077] In one implementation, some of the CO2 formed during the decarboxylation reaction is extracted from the reaction and recycled for use elsewhere.

[0078] In one embodiment, the decarboxylation reaction produces a stream containing rosin oil vapor, which is continuously removed from the decarboxylation reactor. In this embodiment, the separation includes the rosin oil vapor formed by condensation, and preferably, the condensed stream is also distilled to separate fractions with boiling points higher and / or lower than rosin oil, thereby providing purified rosin oil and one or more de-rosin oil streams.

[0079] In one embodiment, the rosin oil formed in step i is at least partially in the form of rosin oil vapor, and the separation in step i includes...

[0080] a. rosin oil vapor formed by condensation; and

[0081] b. Distill the condensed rosin oil to separate fractions with boiling points higher and / or lower than rosin oil, thereby providing purified rosin oil.

[0082] In another embodiment, the separation in step i includes distilling the stream containing the formed rosin oil to provide purified rosin oil and derosin oil streams.

[0083] The derosin oil stream may contain one or more of the above-mentioned compounds, and typically contains at least residual rosin acid. In one embodiment, at least a portion of the derosin oil stream is recycled to the thermal decarboxylation reaction in step c). Preferably, at least a portion of the derosin oil stream is discharged from the process to avoid the accumulation of heavy components such as C(20+) fatty acids, sitosterol, and their esters.

[0084] In one implementation, the separation in step i includes

[0085] a. The liquid stream from step c) is directed to a first evaporator operating at 260°C or above (preferably 300°C or above) to produce a stream containing rosin oil vapor and a stream de-rosin oil; and

[0086] b. Condensing rosin oil vapor to provide a flow of rosin oil and derosinated oil.

[0087] In this embodiment, at least a portion of the derosin oil stream is recycled to the thermal decarboxylation reaction in step c). Preferably, at least a portion of the rosin oil stream is discharged from the process to avoid the accumulation of heavy (C20+) compounds such as fatty acids, esters, and alcohols (e.g., sitosterol and its esters and derivatives).

[0088] In another embodiment, the separation in step i includes

[0089] a. The stream from step c) is directed to a first evaporator operating at 260°C or above (preferably 300°C or above) to produce a stream containing rosin oil vapor and a stream de-rosin oil; b. The stream containing rosin oil vapor and the stream containing derosin oil are directed to a distillation column to separate at least the rosin oil from the stream containing rosin oil vapor, thereby producing purified rosin oil.

[0090] In this embodiment, at least a portion of the derosin oil stream is recycled to the thermal decarboxylation reaction in step c). Preferably, at least a portion of the derosin oil stream is discharged from the process to avoid the accumulation of heavy (C20+) compounds.

[0091] In one embodiment, the method includes recovering rosin acid from the derosin oil stream and recycling at least a portion of the recovered rosin acid to the decarboxylation reaction in step c). This embodiment typically involves directing at least a portion of the derosin oil stream to a second evaporator operating at 260°C or higher (preferably 300°C or higher) to produce a stream containing rosin acid and a stream derosinated, and recycling the stream containing at least a portion of the rosin acid to the thermal decarboxylation reaction. Preferably, the stream containing at least a portion of the rosin acid is discharged from the process to avoid the accumulation of heavy components such as C(20+) fatty acids, sitosterol, and their esters.

[0092] In one embodiment, the thermal decarboxylation reaction in step c) and the separation process in step i are carried out under the same pressure.

[0093] In one embodiment, the thermal decarboxylation reaction in step c) and the separation process in step i are carried out under different pressures.

[0094] In one embodiment, the thermal decarboxylation reaction is carried out at 0.5-20 kPa (a).

[0095] In another embodiment, the thermal decarboxylation reaction is carried out at atmospheric pressure, i.e., 101 kPa (a) or above.

[0096] In an exemplary embodiment, the thermal decarboxylation reaction is carried out at 110 kPa(a) and 325°C, and the separation includes heating the rosin oil-containing stream to 330°C and distilling it at 10 kPa(a).

[0097] The simplest way to recover organic materials from the generated CO2 is through condensation, which involves cooling the CO2-rich gas into a condensate containing liquefied organic materials. This can be achieved more comprehensively than under reduced pressure when operating at or near atmospheric pressure (e.g., about 101 kPa(a)), thus reducing the loss of rosin oil, rosin acid, and other organic materials. Atmospheric operation also allows the use of basic types of condensers, such as shell-and-tube or plate condensers, avoiding the need for more expensive condensers required in vacuum operations.

[0098] In one embodiment, the organic liquid recovered by condensation is directed to a distillation column for refining, while the CO2 stream containing the organic matter is further processed or purified according to its final composition.

[0099] Therefore, this method involves a controlled and enhanced decarboxylation reaction of rosin acid, with the aim of enabling a large portion of feedstocks containing rosin acid (especially CTO) to be used in the production of renewable transportation fuels and / or renewable chemicals and other downstream processes.

[0100] When rosin acid is decarboxylated, it degrades into lighter, neutral components, loses its acid groups, and releases carbon dioxide. This provides reaction products with a significantly lower acidity, or total acid number (TAN), and reduced corrosivity compared to rosin acid. Low acidity is particularly important when rosin oil is co-processed with fossil feedstocks as a renewable feedstock to increase the biorenewable content of fossil transport fuels and / or fossil chemicals.

[0101] In one embodiment, the TAN of the rosin oil product is less than 30 mg KOH / g, preferably less than 10 mg KOH / g, and more preferably less than 2.5 mg KOH / g.

[0102] Depending on the manufacturing method, rosin acid can have a high sulfur content. High-sulfur rosin oil products can be used as a feedstock for fossil fuel refining. However, for the production of renewable fuels and renewable chemicals, desulfurization treatment may be required for these feedstocks.

[0103] In one embodiment, the sulfur content in the rosin acid is less than 700 ppm by weight, preferably less than 600 ppm, more preferably less than 500 ppm, such as less than 400 ppm.

[0104] In one embodiment, the sulfur content in the rosin oil product is less than 300 ppm by weight, preferably less than 150 ppm, more preferably less than 130 ppm, most preferably less than 100 ppm, such as less than 80 ppm or even less than 50 ppm. A low sulfur content is preferred when rosin oil is co-processed with oxygenated renewable feedstocks to produce renewable fuels and / or renewable chemicals or components thereof. Exemplary oxygenated renewable feedstocks are vegetable oils / fats and animal oils / fats, and they preferably include waste and residues derived from animal fats / oils, vegetable fats / oils, or fish fats / oils. These feedstocks contain oxygenated hydrocarbons, such as fatty acids and triglycerides, which must be converted to aliphatic hydrocarbons via hydrodeoxygenation (HDO). For example, 50 ppm by weight of sulfur is sufficient to sulfide some HDO catalysts (such as NiMo and CoMo); higher sulfur contents will only consume the hydrogen required for the hydrodeoxygenation reaction. Low-sulfur rosin oils even allow the use of precious metal-based HDO catalysts.

[0105] This method for producing rosin oil from rosin acid is a continuous process. Continuous operation benefits from hot feed, saving energy by using feed that has been preheated in previous processing steps (such as when using byproducts directly from CTO fractionation or distillation or products directly from refinery feedstock pretreatment). Furthermore, the continuous discharge of rosin oil product from the decarboxylation reaction increases the reaction rate as the concentration of reaction products decreases. Removing the formed rosin oil from the rather harsh decarboxylation reaction conditions also limits its contact with potential side reactions. In addition, the continuous process reduces the need for large processing equipment, thereby reducing investment costs. Therefore, this method includes the continuous removal of the formed rosin oil from the decarboxylation reaction and the separation of the formed rosin oil.

[0106] The rosin oil-containing stream removed from the decarboxylation reaction may still contain unreacted rosin acids. In one embodiment, at least a portion of the de-rosin oil stream is recycled back to the decarboxylation reaction, thereby increasing the overall yield of rosin oil. The recycled de-rosin acid stream can also heat the liquid contents in the decarboxylation reactor. This will satisfy at least a portion of the energy required to maintain the reactor at the desired temperature. In a preferred embodiment, the recycled de-rosin acid stream will satisfy up to 80%, such as 90% or even 100%, of the energy input to the decarboxylation reactor.

[0107] According to another aspect, this disclosure relates to a system for performing the above-described methods. Figure 2 An exemplary system 200 is shown for producing rosin oil from a raw material containing CTO. System 200 includes...

[0108] - Dehydration equipment 201, configured to remove at least water and turpentine from a renewable feedstock containing rosin acid A to provide dehydrated feedstock B; - Deasphalting equipment 202 (such as a stirred thin-film evaporator, thin-film evaporator, and / or distillation column) configured to separate tall oil pitch C from the dehydrated feedstock to produce a stream containing deasphalted tall oil, which contains rosin acid D and fatty acid E. - Distillation column 203, such as a rosin column, is configured to separate a stream containing deasphalted feedstock into at least a defatty acid stream containing rosin acid D and a fatty acid stream E. - Decarboxylation reactor 204, configured to thermally decarboxylate a decarboxylation stream containing at least rosin acid to obtain a stream containing the formed rosin oil F; - Separation device 205, configured to separate rosin oil from a stream containing formed rosin oil to obtain a stream of rosin oil and a stream of derosin oil; and - Circulation device 212, configured to return at least a portion of the decarboxylated rosin oil stream to the decarboxylation reactor.

[0109] In one embodiment, the stream containing the formed rosin oil contains rosin oil vapor, and the separation device 205 is configured to condense the rosin oil vapor into rosin oil. In a preferred embodiment, the system includes a distillation column 205' for separating fractions with boiling points higher and / or lower than rosin oil to provide purified rosin oil.

[0110] In another embodiment, the separation device 205 includes an evaporator ( Figure 2 (Not shown) Such as a thin-film evaporator, which operates at 260°C or above (preferably 300°C or above) to convert a stream containing formed rosin oil into a stream containing rosin oil vapor and a stream de-rosin oil; and a condenser configured to condense rosin oil vapor into rosin oil.

[0111] In another embodiment, the separation device 205 includes an evaporator ( Figure 2 (Not shown) Such as a thin-film evaporator, which operates at 260°C or above (preferably 300°C or above) to convert a stream containing formed rosin oil into a stream containing rosin oil vapor and a de-rosin oil stream; and a distillation column 205', in which fractions with boiling points above and / or below rosin oil are separated to provide purified rosin oil.

[0112] System 200 also includes a circulation device 213 configured to return at least a portion of the de-rosin oil stream d' to the decarboxylation reactor.

[0113] In one embodiment, the circulation unit includes one or more pipelines from the separation unit to the decarboxylation reactor. These pipelines may be equipped with heaters, such as reboilers, electric heaters, shell-and-tube heat exchangers, or evaporators, for heating the decarboxylate stream.

[0114] Typically, the TAN (tannin-containing rosin oil) in the stream effluent from the decarboxylation reactor is at least 70% lower than the TAN of the rosin acid-containing stream entering the reactor, preferably at least 85% lower, more preferably at least 90% lower, and most preferably at least 95% lower. Therefore, depending on the amount of residue in the final product, the TAN of the rosin oil obtainable by the method of this disclosure is typically 50 or less, preferably 30 or less, more preferably 25 or less, even more preferably 15 or less, still more preferably 10 or less, and most preferably 5 or less. The final rosin oil product can be further purified by distillation to further reduce the TAN.

[0115] Optional residue G can be removed from the decarboxylation reaction. Due to its predominantly heavy neutral content and low rosin acid content, it offers high value as a feedstock with low TAN for applications such as renewable fuel / renewable chemical production or co-processing.

[0116] System 200 may further include one or more additional distillation columns, such as a heads column 206 for separating volatiles (e.g., low-boiling fatty acids) from a stream containing high-boiling fatty acids, and a fatty acid separation column 207 for separating high-boiling fatty acids (especially TOFA) and for producing one or more fractions containing residual rosin acid d.

[0117] Tall oil pitch C and fatty acid-containing fraction E may still contain appropriate amounts of rosin acid d. To improve the overall yield of rosin oil, the system preferably includes device 208 for feeding tall oil pitch C containing residual rosin acid d into a thermal decarboxylation reactor; and / or device 209 for feeding one or more fractions containing residual rosin acid d from the fatty acid separation column into the thermal decarboxylation reactor. The system may also include device 210 for feeding rosin acid d from distillation column 203 into decarboxylation reactor 204.

[0118] The thermal decarboxylation reactor is preferably equipped with a heater 211 for maintaining or raising the temperature of the thermal decarboxylation reactor. An exemplary heater comprises hot oil (t > 300°C) that circulates in the jacket or coil of the thermal decarboxylation reactor.

[0119] The system also includes various connections, pipes, valves, etc., known to those skilled in the art for carrying out the method. Various devices also include any suitable inlets and outlets, including outlets for any light gases formed during the various stages of the method.

[0120] In one embodiment, the amount of rosin acid D separated from the dehydrated feedstock B in the deasphalting device 202 is reduced, thus leaving more rosin acid in the tall oil pitch C. This can produce one or more of the following benefits: - It can overcome the production capacity bottleneck that may be caused by deasphalting, while still being able to recover rosin acid for decarboxylation reaction.

[0121] - Overall method throughput increased.

[0122] - Deasphalting 202 and rosin distillation 203 require less energy.

[0123] - Distilled rosin acid is of better quality because the amount of heavy neutral substances that evaporate with rosin acid during the deasphalting process is limited.

[0124] In another embodiment, at least a portion of the rosin acid is distilled off the process as a high-quality rosin acid product D'. Therefore, the amount of rosin acid d fed into reactor 204 via path 210 also increases simultaneously. This, in turn, allows for the separation of rosin acid and rosin oil production according to market demand. Furthermore, less energy is used in rosin distillation due to the reduced amount of D. This is because D is removed from column 203 in vapor form, while d is removed from the column in liquid form. The reduced energy input to 203 also means a lower pressure drop within the column, which is beneficial for the quality and / or yield of fatty acids in fraction E.

[0125] In yet another embodiment, the system includes a device 212 for feeding rosin D'' into a decarboxylation reactor.

[0126] CTO fractionation plants may want to produce barrelled rosin. Since barrels are typically stored at room temperature, rosin often crystallizes inside. Using crystallized rosin is quite difficult because it needs to be melted before it can be used, which requires high temperatures and additional energy input. For traditional rosin users, melting is an extra processing step requiring more production hardware.

[0127] exist Figure 2 In the illustrated method and system, crystalline rosin D'' can be fed into reactor 204 in solid form, preferably pulverized form, or in slurry or liquid form. The feed can be introduced into reactor 204 as its own stream or mixed with one or more other feed streams. This embodiment provides the opportunity to use solid rosin in the process, thereby broadening the potential feedstock combination for decarboxylation methods. Feeding rosin into the decarboxylation reactor may help address logistical and / or market constraints.

[0128] To date, decarboxylation of rosin acid has been considered undesirable, and existing crude tall oil processes are designed to avoid decarboxylation because it dilutes rosin products, and the generated CO2 increases the steam load on the vacuum system. The resulting pressure increase raises the temperature and accelerates all side reactions. However, in this method, a controlled decarboxylation reaction of rosin acid derived from, for example, crude tall oil is desirable, as this yields valuable new renewable feedstocks. Rosin oil is indeed a renewable feedstock with low impurity content and low oxygen content required for renewable fuel production. Therefore, rosin oil has the advantage of being (virtually) oxygen-free, making it ideal for co-processing in situations where oxygen typically poses a challenge. On the other hand, due to its polycyclic structure, rosin oil has a lower hydrogen-to-carbon ratio than, for example, TOFA, resulting in higher hydrogen consumption. Co-processing can mitigate this problem. Furthermore, the decarboxylation of rosin acid facilitates the use of this feedstock, particularly in fossil refineries (co-processing), where the total acid number (TAN) is strictly limited to below 0.5. This means that the feedstock must essentially not contain free fatty acids or any other acids. Using this product in coprocessing also helps prevent corrosion problems in the system and downstream processing equipment.

[0129] According to another aspect, this disclosure relates to an apparatus suitable for producing rosin oil from a stream containing rosin acid, i.e., for carrying out steps c)-d) of the method.

[0130] The device includes

[0131] - A continuous flow reactor configured to carry out a decarboxylation reaction, converting a stream containing rosin acid into a stream containing the formed rosin oil; - A separation device configured to separate at least rosin oil from a stream containing formed rosin oil to produce a stream of rosin oil and a stream of derosin oil; and - A circulation device configured to return at least a portion of the stripped rosin oil stream to a continuous flow reactor.

[0132] The continuous flow reactor is typically a thermal decarboxylation reactor configured to operate at temperatures above 280°C to 360°C. The decarboxylation reaction produces rosin oil and carbon dioxide. Typically, the rosin oil-containing stream includes not only rosin oil and carbon dioxide but also other compounds such as light acids, rosin acids, and heavy residues. The rosin oil is separated from the stream by condensation and / or distillation, while at least a portion of the de-rosin oil-removed stream is returned to the decarboxylation reactor. Exemplary non-limiting apparatus suitable for this method includes… Figure 3-8 As shown.

[0133] exist Figure 3 In the illustrated embodiment, device 300 includes: - A continuous flow reactor 301 is configured to carry out a decarboxylation reaction, converting a stream A containing rosin acid into a stream containing the formed rosin oil; - Separation device 302, configured to separate a stream containing the formed rosin oil into a gaseous portion B ( g ) and liquid portion B ( l The separation device further includes o First evaporator 303, such as a thin-film evaporator or a falling-film evaporator, is configured to convert the liquid portion of a stream containing formed rosin oil into a stream C containing rosin oil vapor. g ) and the flow of pine resin oil; Condenser 304, configured to separate at least rosin oil from a stream containing rosin oil vapor to obtain rosin oil; and - A circulation unit 305 configured to return at least a portion of the decarboxylated rosin oil stream to the decarboxylation reactor.

[0134] use Figure 3 The apparatus shown feeds a stream A containing rosin acid into a thermal decarboxylation reactor 301 to produce a stream containing the formed rosin oil. A gaseous stream B containing rosin oil is then fed... g ) and liquid flow B containing rosin oil l ) is removed from the reactor. Liquid flow B ( l The feed stream B is guided from the reactor to the evaporator 303, such as a thin-film evaporator or a falling-film evaporator. The evaporator operates at 260°C or higher (preferably 300°C or higher) to reheat the feed stream B. l And at least evaporate the rosin oil in the stream. Therefore, a stream C containing rosin oil vapor is formed. g ) and the liquid flow D of depine resin oil l ). The gaseous flow C ( g ) and B ( g The gaseous stream containing rosin oil is directed to condenser 304 to produce rosin oil, while at least partially derosin-oiled liquid stream is returned to the thermal decarboxylation reactor. Preferably, the at least partially derosin-oiled stream is discharged from the recirculation to avoid the accumulation of heavy residues, including C(20+) fatty acids, sitosterols, and their esters, in the apparatus. g The gas is also directed to the condenser to remove light exhaust gases.

[0135] exist Figure 4 In the illustrated embodiment, device 400 includes

[0136] - A continuous flow reactor 401 is configured to carry out a decarboxylation reaction, converting stream A containing rosin acid into stream B containing the formed rosin oil; - Separation device 402, comprising: o First evaporator 403, such as a thin-film evaporator or a falling-film evaporator, is configured to convert a stream containing formed rosin oil into a stream C containing rosin oil vapor. g) and the flow of pine resin oil; o Distillation column 404, configured to separate at least rosin oil from a stream containing rosin oil vapor to obtain purified rosin oil; - A circulation unit 405 configured to return at least a portion of the decarboxylated rosin oil stream to the decarboxylation reactor; and - Optional recovery unit 406, configured to separate rosin acid from the derosin oil stream D and recycle the recovered rosin acid E to the thermal decarboxylation reactor.

[0137] The continuous flow reactor 401 and the distillation column 404 are configured to operate at the same pressure.

[0138] use Figure 4 The apparatus shown feeds stream A, containing rosin acid, into thermal decarboxylation reactor 401 to produce a stream containing rosin oil. A gaseous stream B, containing rosin oil, is then fed into the reactor. g ) and liquid flow B containing rosin oil l ) is removed from the reactor. Flow B ( l The stream B is guided from reactor 401 to first evaporator 403, such as a thin-film evaporator or a falling-film evaporator. The first evaporator, operating at 260°C or above (preferably 300°C or above), reheats the stream B. l And at least the rosin oil in the stream evaporates. Therefore, a stream C containing rosin oil vapor is formed. g The distillation process generates a liquid stream D containing rosin oil and desorbed rosin oil. These streams are directed to a distillation column 404 to produce purified rosin oil, while at least partially desorbed rosin oil stream D is returned from the distillation column to the decarboxylation reactor and / or directed to an optional second evaporator 407, such as a thin-film evaporator or a falling-film evaporator, in a recovery unit. The second evaporator, operating at 260°C or higher (preferably 300°C or higher), recovers rosin acid from the desorbed rosin oil stream D, producing a stream E containing rosin acid and a residue containing desorbed rosin acid. The stream containing the recovered rosin acid is recycled to the decarboxylation reactor, while the stream containing at least partially desorbed rosin acid is discharged from the circulation to avoid the accumulation of heavy residues, including components such as C(20+) fatty acids, sitosterols, and their esters, in the unit.

[0139] The decarboxylation reactor 401 also includes an outlet 408 for a gaseous stream B containing rosin oil. g This includes light off gas, as well as residual rosin oil c ( g It can be guided to the distillation column (in Figure 4 (marked with a dashed line).

[0140] In one implementation, at least a portion of flow B ( gThe fluid is guided from the decarboxylation reactor 401 to the bottom of the distillation column 404 (not shown) before being directed to the first evaporator 403. This is because at least a portion of the flow B (…) l Evaporation occurs in a distillation column, resulting in less vapor formation in the evaporator. This, in turn, improves gas-liquid separation in the evaporator.

[0141] Figure 4 The device shown is more Figure 3 The apparatus shown is more complex, but it can more effectively recover residual rosin acid and purify rosin oil more efficiently through distillation. If desired, it also allows for the separation of other components, such as light acids like saturated and unsaturated C3-C18 carboxylic acids, by distillation.

[0142] exist Figure 5 In the illustrated embodiment, the device 500 includes: - A continuous flow reactor 501 configured to carry out a decarboxylation reaction, converting a stream A containing rosin acid into a stream containing the formed rosin oil B; - Separation device 502, comprising: o First evaporator 503, such as a thin-film evaporator or a falling-film evaporator, is configured to convert a stream containing formed rosin oil into a stream C containing rosin oil vapor. g ) and the flow of pine resin oil; o Distillation column 504, configured to separate at least rosin oil from a stream containing rosin oil vapor to obtain purified rosin oil; - Circulation unit 505, configured to return at least a portion of the decarboxylated rosin oil stream D to the thermal decarboxylation reactor; and - Optional recovery unit 506, configured to separate rosin acid from the derosin oil stream and recycle the recovered rosin acid E to the thermal decarboxylation reactor.

[0143] use Figure 5 The apparatus shown feeds stream A, containing rosin acid, into thermal decarboxylation reactor 501 to produce a stream containing rosin oil. A gaseous stream B, containing rosin oil, is then fed into the reactor. g ) and liquid flow B containing rosin oil l ) is removed from the reactor. Liquid stream B containing rosin oil l The rosin oil from the decarboxylation reactor 501 is directed to the first evaporator 503, such as a thin-film evaporator or a falling-film evaporator. The evaporator, operating at 260°C or higher (preferably 300°C or higher), reheats the stream and at least evaporates the rosin oil in the stream. Thus, a stream C containing rosin oil vapor is formed. gThe stream contains a liquid D containing derosin oil. This stream is directed to a distillation column 504 to produce purified rosin oil, while the stream D containing at least partially derosin oil is directed from the distillation column to a decarboxylation reactor 501 and / or an optional second evaporator 507, such as a thin-film evaporator or a falling-film evaporator, of an optional recovery unit 506. The second evaporator, operating at 260°C or above (preferably 300°C or above), recovers rosin acid from the derosin oil stream D, thereby producing a stream E containing rosin acid and a residue containing derosin acid. The stream containing rosin acid is recycled to the thermal decarboxylation reactor, while the residue containing at least partially derosin acid is discharged from the circulation to avoid the accumulation of heavy residues, including components such as C(20+) fatty acids, sitosterols, and their esters, in the unit.

[0144] The gaseous stream B(g) is also directed to the distillation column because it may contain some rosin oil vapor c(g).

[0145] Figure 5 The device is similar to Figure 4 The apparatus 500 includes a thermal decarboxylation reactor 501, but the thermal decarboxylation reactor 501 is configured to operate at a higher pressure than the distillation column 504. Therefore, the apparatus 500 also includes devices for reducing and increasing pressure between the decarboxylation reactor and the recovery unit, such as a pressure reducing device 508, a flash tank 509, and a pump 511. The flash tank serves to allow the liquid to evaporate in a controlled manner before it is introduced into the distillation column. The apparatus also includes an optional line 512 for transporting the evaporation stream B containing rosin oil (… g The material is guided from the flash tank to the distillation column. Typically, the recovery unit 505 also includes at least one additional heating device 513, such as a reboiler, electric heater, shell-and-tube heat exchanger, or evaporator, for heating the material configured to be returned to the decarboxylation reactor.

[0146] Using higher pressures in the thermal decarboxylation reactor than in the distillation column prevents the material from evaporating from the decarboxylation reactor.

[0147] Figure 6 The device 600 shown includes

[0148] - A continuous flow reactor 601, configured to perform a decarboxylation reaction, converting stream A containing rosin acid into stream B containing the formed rosin oil. The continuous flow reactor includes...

[0149] o For gaseous flow B containing rosin oil ( g The first exit, 608; o For liquid flow B containing rosin oil ( l The second exit, 609; - Separation device 602, comprising: o First evaporator 603, such as a thin-film evaporator or a falling-film evaporator, is configured to deliver a liquid stream B containing rosin oil (l ) is converted into a stream containing rosin oil vapor C ( g ) and the flow of pine resin oil; o Condenser 610, configured to produce a liquid stream C containing rosin oil ( l And used to remove light exhaust gases; o Distillation column 604, configured to separate at least rosin oil from a rosin oil-containing stream to obtain purified rosin oil and a rosin-free stream D; - A circulation unit 605 configured to return at least a portion of the decarboxylated rosin oil stream D to a thermal decarboxylation reactor; and - Optional recovery unit 606, configured to separate rosin acid from the derosin oil stream D and recycle the recovered rosin acid E to the decarboxylation reactor.

[0150] use Figure 6 The apparatus shown feeds stream A, containing rosin acid, into a thermal decarboxylation reactor 601 to produce a stream containing rosin oil. A gaseous stream B, containing rosin oil, is then fed into the reactor. g ) and liquid flow B containing rosin oil l Removed from the reactor.

[0151] A liquid stream containing rosin oil is directed from reactor 601 through outlet 609 to a first evaporator 603, such as a thin-film evaporator or a falling-film evaporator. The evaporator, operating at 260°C or higher (preferably 300°C or higher), reheats the stream and at least evaporates the rosin oil in it. Thus, a stream C containing rosin oil vapor is formed. g ) and liquid D of depine resin oil.

[0152] Gas flow B containing rosin oil g The gas is directed from the reactor through outlet 608 to the condenser to remove light waste gas and produce a liquid stream C containing rosin oil. l ).

[0153] Flow C ( l ), C ( g Streams D and E are directed to distillation column 604 to produce purified rosin oil, while at least partially derosin-treated stream D is directed from the distillation column via circulation unit 605 back to an optional second evaporator 607, such as a thin-film evaporator or falling-film evaporator, in the decarboxylation reactor or recovery unit 606. The second evaporator, operating at 260°C or higher (preferably 300°C or higher), separates rosin acid from the derosin-treated stream D, producing stream E containing rosin acid and a residue containing derosin acid. The stream containing rosin acid is recycled to the decarboxylation reactor, while the residue containing derosin acid is discharged from the circulation to avoid the accumulation of heavy residues, including C(20+) fatty acids, sitosterols, and their esters, in the unit. The second outlet preferably faces the bottom of the distillation column (not shown in the figure).

[0154] The decarboxylation reactor 601 is configured to operate at a different pressure than the distillation column 604. Therefore, the apparatus also includes means for reducing and increasing pressure between the decarboxylation reactor and the separation unit, such as one or more pressure regulating devices 611, 612 and a pump 613. The apparatus also includes a condenser 610 for condensing rosin oil-containing stream B (… g The lighter gaseous components are removed in the process to produce a liquid stream C containing rosin oil. l The apparatus also includes a heating element 614, such as a boiler, for heating the derosin oil stream D and / or the stream E containing recovered rosin oil; and a heating jacket 615 for heating the reactor. In one embodiment, the heating element 614 is a third evaporator operating at 260°C or above, preferably 300°C or above, configured to separate rosin acid from the derosin oil stream D, which is guided from the distillation column to the decarboxylation reactor, thereby producing a stream containing rosin acid E and a residue of derosin acid. The rosin acid-containing stream is returned to the decarboxylation reactor, while the derosin acid stream d, which may still contain rosin acid, is returned to the distillation column.

[0155] Figure 7 The device 700 shown includes

[0156] - A continuous flow reactor 701, configured to perform a decarboxylation reaction, converting stream A containing rosin acid into a stream containing the formed rosin oil B. The continuous flow reactor contains...

[0157] o For gaseous flow B containing rosin oil ( g The first exit, 708; o For liquid flow B containing rosin oil ( l The second exit 709; - Separation device 702, comprising: o First evaporator 703, such as a thin-film evaporator or a falling-film evaporator, is configured to deliver a liquid stream B containing rosin oil ( l ) is converted into a stream containing rosin oil vapor C ( g ) and the flow of pine resin oil; o Distillation column 704, configured to distill from stream C containing rosin oil vapor ( g ) and gaseous flow B containing rosin oil g At least the rosin oil must be separated in the process to obtain purified rosin oil and a derosin oil stream; - A circulation unit 705 configured to return at least a portion of the decarboxylated rosin oil stream D to a thermal decarboxylation reactor; and - Optional recovery unit 706, configured to separate rosin acid from the derosin oil stream D and recycle the recovered rosin acid E to the decarboxylation reactor.

[0158] use Figure 7 The apparatus shown feeds stream A, containing rosin acid, into thermal decarboxylation reactor 701 to produce a stream containing rosin oil. A gaseous stream B, containing rosin oil, is also produced. g ) and liquid flow B containing rosin oil l The ions are removed from the reactor through outlets 708 and 709, respectively.

[0159] Liquid flow B ( l This may include heavy residues accumulated at the bottom of the reactor, while the gaseous stream B ( g It contains light exhaust gases.

[0160] A liquid stream containing rosin oil is directed from reactor 701 to a first evaporator 703, such as a thin-film evaporator or a falling-film evaporator. The evaporator, operating at 260°C or higher (preferably 300°C or higher), reheats the stream and at least evaporates the rosin oil in the stream. Thus, a stream C (g) containing rosin oil vapor and a liquid D containing derosin oil are formed.

[0161] Flow C ( g B () g Streams D and D are directed to distillation column 704 to produce purified rosin oil, while at least partially derosin-treated stream D is directed from the distillation column via circulation unit 705 back to an optional second evaporator 707, such as a thin-film evaporator or falling-film evaporator, in the decarboxylation reactor and / or recovery unit 706. The optional second evaporator, operating at 260°C or above, preferably 300°C or above, separates rosin acid from stream D, thereby producing stream E containing rosin acid and a residue containing derosin acid. The stream containing recovered rosin acid is recycled to the thermal decarboxylation reactor, while the residue containing derosin acid is discharged from the circulation to avoid the accumulation of heavy residues, including components such as C(20+) fatty acids, sitosterols, and their esters, in the unit.

[0162] The apparatus 700 is similar to the apparatus 600, but the thermal decarboxylation reactor 701 and distillation column 703 are configured to operate at the same pressure. The apparatus also includes at least one heating device 710 for heating the stream circulating to the decarboxylation reactor and a heating jacket 711 for heating the reactor. Figure 6 Unlike other devices, device 700 can effectively strip rosin oil and rosin acid using CO2 generated during the reaction process, thereby increasing the yield of rosin oil. In one embodiment, heating device 710 is a third evaporator operating at 260°C or above, preferably 300°C or above, configured to separate rosin acid from the decarboxylated rosin oil stream D guided from the distillation column to the decarboxylation reactor, thereby producing a stream E containing rosin acid and a residue containing decarboxylated rosin acid. The stream containing rosin acid is returned to the decarboxylation reactor, while the stream d containing decarboxylated rosin acid, which may still contain rosin acid, is returned to the distillation column.

[0163] Figure 8 Another apparatus suitable for producing rosin oil from a stream containing rosin acid is shown. This apparatus is similar to... Figure 7 The apparatus 800 comprises, but when in the operating position, the distillation column 804 of the separation unit 802 is located above the decarboxylation reactor 801. Therefore, the apparatus 800 includes...

[0164] - A continuous flow reactor 801 is configured to carry out a decarboxylation reaction, converting stream A containing rosin acid into stream B containing the formed rosin oil; - Separation device 802, which includes a distillation column 804 integrated into a continuous flow reactor, the distillation column being configured to separate at least rosin oil from a stream containing formed rosin oil; - A circulation device 805 configured to return at least a portion of the decarboxylated rosin oil stream to the decarboxylation reactor; - Optional recovery unit 806, configured to separate rosin acid from the derosin oil stream to obtain a stream containing recovered rosin acid and a derosin acid stream, and to return at least a portion of the stream containing rosin acid to the thermal decarboxylation reactor.

[0165] Using device 800, including a gaseous stream B containing carbon dioxide and rosin oil ( g The rosin oil-containing liquid stream B flows directly upwards from the decarboxylation reactor to distillation column 804 to recover rosin oil. l The rosin oil is guided from the bottom of the decarboxylation reactor to the first evaporator 803, such as a thin-film evaporator or a falling-film evaporator. The evaporator, operating at 260°C or higher (preferably 300°C or higher), reheats the stream and at least evaporates the rosin oil in the stream. Thus, a stream C containing rosin oil vapor is formed. g ) and liquid D of depine resin oil. Flow C ( g The rosin oil is directed to distillation column 804 to produce purified rosin oil, while at least partially derosin-treated stream D is directed from the first evaporator via circulation unit 805 back to an optional second evaporator 807, such as a thin-film evaporator or falling-film evaporator, in recovery unit 806. The optional second evaporator, operating at 260°C or above (preferably 300°C or above), separates rosin acid from the derosin-treated stream D, producing stream E containing rosin acid and a residue containing derosin acid. The stream containing recovered rosin acid is recycled to the thermal decarboxylation reactor, while the residue containing at least partially derosin acid is discharged from the circulation to avoid the accumulation of heavy residues, including C(20+) fatty acids, sitosterols, and their esters, in the unit.

[0166] This integration reduces the footprint and requires fewer pumps and interconnecting pipes.

[0167] In one embodiment, the apparatus includes means for introducing a non-condensable stripping gas (such as carbon dioxide, steam, or nitrogen, preferably carbon dioxide formed in a decarboxylation reaction) into the distillation column of the apparatus. Figure 9 Unrestricted instances are shown. Figure 9 In the embodiment shown in A, the apparatus includes an ejector 908 located upstream of the second evaporator 907a for feeding stripping gas. The ejected carbon stripping gas reduces the operating pressure of the evaporator to below the operating pressure in the distillation column (e.g., 5 kPa(a) vs. 10 kPa(a)). Stripping in the distillation column is also enhanced.

[0168] exist Figure 9 In embodiment B, the stripping gas is fed into the second evaporator 907b through inlet 909. The pressure of the stripped carbon dioxide is the same as the pressure inside the unit. Due to the increased amount of stripping gas in the unit, the recovery rate of rosin oil also increases.

[0169] The apparatus disclosed herein (such as) Figure 4-7 Those disclosed herein can also be used to produce high-purity rosin acid by guiding a stream containing rosin acid, A, to distillation columns 404, 504, and 604 (i.e., via decarboxylation reactors 401, 501, and 601 (marked with dashed lines in the figure)). Therefore, these apparatuses are suitable for, for example, producing rosin oil and rosin acid depending on market demand.

[0170] According to another aspect, this disclosure relates to a rosin oil product obtainable by the above method. The rosin oil product comprises: The rosin oil content is greater than 85 wt%, preferably greater than 90 wt%, more preferably greater than 95 wt%, and most preferably greater than 97 wt%. 0.1-10 wt%, preferably 0.1-5 wt%, more preferably 0.1-2 wt%, and most preferably 0.5-2 wt% of rosin acid; Other neutral components, ranging from 0.1% to 5 wt% (e.g., 0.1% to 5 wt%). 0-5wt% (e.g., 0.1-5wt%) of light acid; and Heavy (C20+) compounds, ranging from 0-3 wt% (e.g., 0.1-3 wt%).

[0171] In one embodiment, the other neutral components include alcohols, esters, ethers, aldehydes, ketones, or hydrocarbons other than rosin oil, such as turpentine and its derivatives.

[0172] In one embodiment, the light acid comprises a saturated or unsaturated C3-C18 carboxylic acid.

[0173] In one embodiment, the heavy (C20+) compound comprises fatty acids, esters, and alcohols, such as sitosterol and its esters and derivatives.

[0174] In one embodiment, the rosin oil product contains 85-97 wt%, such as 90-97 wt% or 95-97 wt% of at least one decarboxylation product of abietic acid (CAS No. 514-10-3), isopyric acid (CAS No. 5835-26-7), L-piperic acid (CAS No. 79-54-9), neo-piperic acid (CAS No. 471-77-2), longleaf abietic acid (CAS No. 1945-53-5), piratic acid (CAS No. 127-27-5), santalinic acid (CAS No. 471-74-9), and dehydropiperic acid (CAS No. 1740-19-8).

[0175] In one embodiment, the total tannin (TAN) of the rosin oil product is less than 30 mg KOH / g, preferably less than 20 mg KOH / g, more preferably less than 10 mg KOH / g, and most preferably less than 2.5 mg KOH / g. In another embodiment, the TAN of the rosin oil product is between 0.51 and 30 mg KOH / g, such as 12-10 mg KOH / g, or even 1.5-2.5 mg KOH / g. Using a low-TAN rosin oil product as a feedstock for downstream processing can reduce equipment corrosion and lower the total TAN of the feedstock.

[0176] In one embodiment, the total amount of metallic impurities (such as Al, As, Ba, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Si, V, Zn) in the rosin oil product is less than 20 ppm by weight. From a downstream processing perspective, a low content of metallic impurities in the rosin oil product is desirable.

[0177] In one embodiment, the sulfur content in the rosin oil product is less than 300 ppm, preferably less than 150 ppm, most preferably less than 130 ppm, such as less than 100 ppm, less than 80 ppm, or even less than 50 ppm (as elemental sulfur). Depending on the source of the rosin acid used to manufacture the rosin oil product, the sulfur content of the product may be very low, such as 0.1 to 30 ppm, or even 0.1 to 10 ppm. The rosin oil product can even be substantially sulfur-free. Consider using the rosin oil product as feedstock for downstream processing (such as catalytic hydrotreating); low-sulfur or sulfur-free feedstocks can use precious metal catalysts.

Claims

1. A process for producing rosin oil, the process comprising the steps of: a) providing a renewable material comprising rosin acids; b) separating at least part of the rosin acids from the renewable material; c) subjecting a stream comprising at least part of the separated rosin acids to a thermal decarboxylation reaction at a temperature of greater than 280°C to 360°C for a time sufficient to provide a conversion of at least 90% of the rosin acids to form rosin oil, and continuously removing from the thermal decarboxylation reaction a stream comprising the formed rosin oil; and d) recovering the formed rosin oil.

2. The method of claim 1, wherein, The process further comprises the following steps after step c) and before step d): i. separating the formed rosin oil from the stream comprising the formed rosin oil and a stream depleted in rosin oil; and ii. recycling at least part of the stream depleted in rosin oil to the thermal decarboxylation reaction of step c).

3. The method of claim 2, wherein, The stream comprising the formed rosin oil contains a liquid phase and a gas phase, and the formed rosin oil is separated from at least one of the phases.

4. The method of claim 3, wherein, Recovering the formed rosin oil from the liquid phase comprises a. directing the liquid phase to a first evaporator operating at 260°C or above, preferably at 300°C or above, to produce a stream comprising rosin oil vapour and a stream depleted in rosin oil; and b. subjecting the stream comprising rosin oil to distillation and / or condensation, thereby providing purified rosin oil.

5. The method of claim 3 or 4, wherein, Recovering the formed rosin oil from the gas phase comprises condensing and / or distilling rosin oil from the gas phase, thereby providing purified rosin oil.

6. The process according to any one of claims 2 to 5, comprising feeding an incondensable gas, such as carbon dioxide, steam or nitrogen, preferably carbon dioxide formed in the decarboxylation reaction, to the separation of step i.

7. The method of any one of claims 2 to 6, wherein, The thermal decarboxylation reaction of c) and the separation of step i) are carried out at the same pressure.

8. The method of any one of claims 2 to 6, wherein, The thermal decarboxylation reaction of c) and the separation of step i) are carried out at different pressures.

9. The method of any one of claims 1 to 8, wherein, The thermal decarboxylation reaction of step c) is at 0.1 to less than 20 kPa (a), such as 0.5 to less than 20 kPa (a).

10. The method of any one of claims 1 to 9, wherein, The thermal decarboxylation reaction of step c) is at 20 to 110 kPa (a).

11. The method of any one of claims 1 to 10, wherein, The renewable material comprises at least 20 wt% rosin acids, preferably at least 90 wt% rosin acids.

12. The method of any one of claims 1 to 11, wherein, The renewable material comprises crude tall oil (CTO), tall oil pitch, distilled tall oil, tall oil rosin or tall oil, preferably CTO.

13. The method of any one of claims 1 to 12, wherein, The renewable material comprises at least 50 wt% CTO, preferably at least 90 wt% CTO.

14. The process according to any one of claims 2 to 13, comprising a. recovering rosin acids from the stream depleted in rosin oil, thereby providing a stream comprising rosin acids and a stream depleted in rosin acids; and b. recycling at least part of the stream comprising rosin acids to the decarboxylation reaction of step c).

15. The method of any one of claims 1 to 14, wherein, The renewable material comprises CTO, and wherein step b) comprises i) subjecting at least part of the renewable material to dewatering to produce a dewatered renewable material, ii) subjecting the dewatered renewable material to pitch removal to produce a. a fraction comprising tall oil pitch, and b. a fraction comprising pitch-removed tall oil; iii) subjecting the fraction comprising pitch-removed tall oil to separation to produce a. a fatty acid containing stream, and b. a defatted fatty acid stream containing isolated rosin acids.

16. The method of claim 15, wherein, The rosin acid containing fraction of the tall oil pitch contains rosin acids, and the method comprises a. subjecting the rosin acid containing fraction of the tall oil pitch to a thermal decarboxylation reaction at a temperature of greater than 280°C to 360°C for a time sufficient to provide a conversion of at least 90% of the rosin acids, and continuously removing formed rosin oil from the thermal decarboxylation reaction; and b. recovering the formed rosin oil. The fatty acid containing stream comprises rosin acids, and the method comprises 17. The method of claim 15 or 16, wherein, a. subjecting the fatty acid containing stream to distillation to produce i. a fraction comprising fatty acids and ii. one or more fractions comprising rosin acids, and b. subjecting at least a portion of the one or more fractions comprising rosin acids to the thermal decarboxylation reaction. The method comprises separating the rosin acid containing defatted fatty acid stream into at least one of:

18. The method of any one of claims 15-17, wherein, a. a first rosin acid fraction in a gas phase, b. a second rosin acid fraction in a liquid phase, and c. a third rosin acid fraction in a solid phase, before step c), at a temperature of 150°C or above and at a pressure of about 2 kPa, and wherein at least one fraction is subjected to the thermal decarboxylation reaction. The thermal decarboxylation reaction of step c) has a residence time of 3 h to 12 h, such as 8 h to 12 h.

19. The method of any one of claims 1 to 18, wherein, The TAN of the rosin oil is reduced by at least 70%, preferably at least 85%, more preferably at least 90%, most preferably at least 95% compared to the TAN of the rosin acids.

20. The method of any one of claims 1 to 19, wherein, 21. Use of rosin oil obtained according to the method of any one of claims 1 to 20 as a renewable feedstock co-processed with fossil feedstock to increase the renewable content of fossil transportation fuels and / or chemicals.

22. Use of rosin oil obtained according to the method of any one of claims 1 to 20 co-processed with other renewable feedstocks to produce renewable fuels and / or chemicals, or components thereof.

23. A system (200) for carrying out the method of claim 2, wherein the renewable material comprises crude tall oil, the system comprising - a dewatering device (201) configured to remove at least water and turpentine from the feedstock; - a deasphalting device (202) configured to separate tall oil pitch from the dewatered feedstock to produce a fraction comprising tall oil pitch and a fraction comprising deasphalted tall oil; - a separation device (203) configured to separate the deasphalted tall oil into a rosin acid containing defatted fatty acid stream and a fatty acid containing stream; - a decarboxylation reactor (204) configured to subject the rosin acid containing defatted fatty acid stream to a decarboxylation reaction to obtain a stream comprising formed rosin oil; - a separation device (205) configured to separate rosin oil from the stream comprising formed rosin oil to obtain rosin oil and a stream of de-rosin oil; and - a recycling device configured to return at least part of the stream of de-rosin oil to the decarboxylation reactor. The stream comprising formed rosin oil comprises rosin oil vapour, and wherein the separation device (205) is configured to condense the rosin oil vapour into rosin oil.

24. The system of claim 23, wherein, ​ 25. The system according to claim 23 or 24, comprising a distillation column (205') for separating a fraction having a higher and / or lower boiling point than rosin oil to provide purified rosin oil.

26. The system according to any one of claims 23 to 25, comprising at least one separation device (207) configured to separate the stream comprising fatty acids into a distillate comprising fatty acids and one or more fractions comprising rosin acids.

27. The system according to any one of claims 23 to 26, comprising a device (208) configured to feed the fraction comprising tall oil pitch into the decarboxylation reactor.

28. The system according to claim 26 or 27, comprising a device (209) configured to feed the one or more fractions comprising rosin acids into the decarboxylation reactor.

29. The system of any one of claims 23 to 28, wherein, The decarboxylation reactor is equipped with a heater (211) for maintaining or increasing the temperature of the decarboxylation reactor.

30. A device for carrying out the method according to steps c) - d) of claim 2, the device comprising - a continuous flow reactor (301, 401, 501, 601, 701, 801) configured to perform a decarboxylation reaction on a stream comprising rosin acids and to obtain a stream comprising rosin oil; - a separation device (302, 402, 502, 602, 702, 802) configured to separate at least rosin oil from the stream comprising rosin oil to obtain a stream comprising formed rosin oil and a stream depleted in rosin oil; and - a recycling device (303, 403, 503, 603, 703, 803) configured to return at least part of the stream depleted in rosin oil to the continuous flow reactor.

31. The apparatus of claim 30, wherein, The separation device (302) comprises a first evaporator (303) configured to operate at 260°C or above, preferably at 300°C or above, to produce a stream comprising rosin oil vapor and a stream depleted in rosin oil; and a condenser (304) configured to condense the rosin oil vapor.

32. The apparatus of claim 30, wherein, The separation device (402, 502, 602, 702) comprises a first evaporator (403, 503, 603, 703) configured to operate at 300°C or above to produce a stream comprising rosin oil vapor and a stream depleted in rosin oil; and a distillation column (404, 504, 604, 704) configured to separate at least rosin oil from the stream comprising rosin oil vapor.

33. The apparatus of claim 30, wherein, The separation device (802) comprises a distillation column (804) integrated to the thermal decarboxylator (801) and configured to separate at least rosin oil from a stream comprising rosin oil.

34. The apparatus of any one of claims 30-33, wherein, The recycling device comprises at least one heating device (513, 713, 803) configured to heat the stream depleted in rosin oil to 260°C or above, preferably 300°C or above.

35. The device according to any one of claims 30 to 34, comprising a recovery device (406, 506, 606, 706, 806) configured to separate rosin acids from the stream depleted in rosin oil to obtain a stream comprising recovered rosin acids and a stream depleted in rosin acids, and to recycle at least part of the stream comprising recovered rosin acids to the thermal decarboxylation reactor.

36. The apparatus of claim 35, wherein, The recovery device comprises a second evaporator (407, 507, 607, 707, 807, 907a, b) configured to operate at 260°C or above, preferably at 300°C or above.

37. The apparatus according to claim 36, comprising an eductor (908) upstream of the second evaporator (907a) and configured to direct stripping gas to the separation device.

38. The apparatus of claim 36, wherein, The second evaporator (907b) comprises an inlet (909) for stripping gas.

39. A rosin oil product obtainable by the method according to any one of claims 1 to 20, comprising: more than 85 wt%, preferably more than 90 wt%, more preferably more than 95 wt%, most preferably more than 97 wt% rosin oil; 0.1 - 10 wt%, preferably 0.1 - 5 wt%, more preferably 0.1 - 2 wt%, most preferably 0.5 - 2 wt% abietic acid; 0 - 5 wt%, such as 0.1 - 5 wt% other neutral components; 0 - 5 wt%, such as 0.1 - 5 wt% light acids; and 0 - 3 wt%, such as 0.1 - 3 wt% heavy (C20+) compounds.

40. The rosin oil product according to claim 39, comprising 85 - 97 wt%, such as 90 - 97 wt% or 95 - 97 wt% decarboxylation reaction products of at least one of abietic acid, isohomopimaric acid, levopimaric acid, neokauric acid, palustric acid, pimaric acid, sandaracopimaric acid and dehydroabietic acid.

41. The rosin oil product of claim 39 or 40, wherein, The rosin oil product has a TAN of less than 30 mg KOH / g, preferably less than 20 mg KOH / g, more preferably less than 10 mg KOH / g, most preferably less than 2.5 mg KOH / g, in one embodiment the rosin oil product has a TAN of 0.51 - 30 mg KOH / g, such as 12 - 10 mg KOH / g, or even 1.5 - 2.5 mg KOH / g.

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