Process for production of renewable hydrocarbons from renewable feedstocks comprising phosphorus as impurities

Abstract

Provided herein are methods for producing renewable hydrocarbons suitable for use in fuel applications from renewable feedstocks. The feedstock comprises at least one lipophilic phosphorus compound which is difficult to remove therefrom by conventional purification methods. The amount of such "difficult-to-remove" phosphorus is determined and the result thereof is used to select a suitable subsequent purification of the feedstock. The purified renewable feedstock may then be catalytically hydrotreated.

Description

Technical Field

[0001] The present disclosure generally relates to the production of hydrocarbon compositions. The present disclosure particularly (but not exclusively) relates to the production of hydrocarbon compositions by catalytic conversion from low-quality (i.e., impure or dirty) feedstocks. Further, the present disclosure relates to an analytical method that supports the selection of pre-treatment to be used on the feedstock prior to said catalytic conversion. Background Art

[0002] This section sets forth useful background information, but does not admit that any of the techniques described herein represents the state of the art.

[0003] Treating vegetable oils to remove phosphorus is a routine procedure, and currently there are a variety of methods available for bleaching and degumming vegetable oils, specifically water degumming techniques, acid degumming techniques, enzymatic degumming techniques, and membrane degumming techniques. The standard analysis for determining the total phosphorus content in a sample, such as an oil or fat sample, is a routinely used procedure and is widely available. However, these simple and low-cost methods developed for edible oils do not have sufficient information content for the analysis of low-quality oils and fats used for fuel production, as they are unable to distinguish between different types of P impurities that may be found in the low-quality feedstock pool.

[0004] In renewable feedstocks, phosphorus is a key impurity and catalyst deactivator that needs to be removed as effectively as possible to support the long life of hydrotreating catalysts. The presence of phosphorus in the feed may cause catalyst deactivation and reactor fouling in hydrotreating due to the formation and precipitation of phosphorus-containing compounds, such as salts. For example, prior art phosphorus removal is discussed in US2013116491 A1, US2013116490A1, EP3666866 A1, and US2011138680. As the lipid feedstock pool for hydrocarbon production increasingly expands to low-quality wastes and residues, phosphorus may occur in forms that are not affected by common purification processes, and thus so-called "difficult-to-remove phosphorus" is encountered in increasing amounts in an increasing number of feedstocks.

[0005] The hydrophilicity of phospholipids is a well-known property of phospholipid compounds in the field of fat and oil chemistry. Dividing phospholipids into hydratable phospholipids and non-hydratable phospholipids has practical significance for understanding how effective the purification of fats or oils is in water degumming. There is some ambiguity in this division, as adjusting the pH in degumming changes the division between hydratable and non-hydratable phospholipids. Non-hydratable phospholipids can be considered part of the lipophilic phosphorus compounds that are of particular interest here, but the concept of lipophilic phosphorus compounds has far greater chemical diversity than just phospholipids. Further, the concept of lipophilic phosphorus compounds applies to all types of lipid feedstocks and the P impurities contained therein, as well as to feedstocks that do not contain any phospholipids or their derivatives or degradation products.

[0006] Although phospholipids are the most discussed phosphorus impurities in oils and fats, and the formation of lipophilic phospholipid derivatives is the expected pathway for lipophilic P, the concept of lipophilic phosphorus is by no means limited to phospholipid origin. With the increasing characteristics of feed waste and residues, the possibility of contamination by other yet-to-be-identified phosphorus sources increases, and these phosphorus sources may themselves be lipophilic, or although initially not having lipophilic precursors, they may have become lipophilic after further degradation reactions during the processing or logistics history of lipid feeds. Due to the lack of knowledge of the exact structure of many lipophilic phosphorus impurities or their origin, it is of great practical significance to be able to evaluate and quantify the total parameters of these impurities in order to be able to identify industrial feeds with P purification challenges and expected behaviors suitable for catalytic hydrotreating processes.

[0007] Therefore, there is a need to be able to evaluate and analyze lipophilic phosphorus compounds as impurities in feeds in order to be able to identify suitable industrial feeds with expected behaviors regarding phosphorus compounds. In addition, there is a need to reasonably select pre-treatments to remove, minimize or at least control the amount of lipophilic phosphorus compounds therein. Summary of the Invention

[0008] The appended claims define the scope of protection. Any examples or descriptions of devices, systems, products or methods in the specification, claims and / or drawings not covered by the claims are not considered embodiments of the present invention herein, but are considered as background art or examples useful for understanding the present invention.

[0009] According to a first aspect, there is provided a method for producing renewable hydrocarbons suitable for use in fuel and biochemical applications from a renewable feedstock comprising at least one or more lipophilic phosphorus compounds, the method comprising the following steps:

[0010] (i) providing a renewable feedstock, wherein the total amount of lipophilic phosphorus compounds calculated as elemental phosphorus is greater than 2 wppm of the total feedstock weight;

[0011] (ii) subjecting the renewable feedstock to at least one pre-treatment to obtain a pre-treated renewable feedstock, wherein the total amount of lipophilic phosphorus compounds calculated as elemental phosphorus is lower than the total amount of lipophilic phosphorus compounds of the renewable feedstock in step (i), preferably less than 2 wppm of the weight of the pre-treated feedstock, preferably less than 1.5 ppm;

[0012] (iii) subjecting the pre-treated renewable feedstock to at least one catalytic hydrotreating step to obtain renewable hydrocarbons.

[0013] Preferably, the steps are carried out in the order (i), (ii), (iii). The inventors have unexpectedly found that the method provides less deposit formation on the catalyst during long-term use and thus enhances the catalyst life.

[0014] According to a second aspect, there is provided a use of separating and analyzing data providing information on at least one lipophilic phosphorus compound in a renewable feedstock in the catalytic production of renewable hydrocarbons, the use further comprising, based on the separation and analysis, selecting a pretreatment capable of reducing the lipophilic phosphorus compound content to below a critical level, and subjecting the renewable feedstock to the selected pretreatment to provide a pretreated renewable feedstock.

[0015] The inventors have unexpectedly found that by hydrotreating a feedstock having a sufficiently low amount of lipophilic phosphorus compound, the use provides better control of the catalytic process, and the pretreatment is selected based on the data obtained by the separation and analysis.

[0016] Generally for the first and second aspects, by knowing the content of lipophilic phosphorus compounds rather than the total phosphorus content, the methods and uses of the present invention provide a way to select a pretreatment or combination of pretreatments suitable for the feedstock, as confirmed by the results shown in the examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Some example embodiments will be described with reference to the accompanying drawings, in which:

[0018] Figure 1 Shows the separation results of lipophilic P (A and B) and amphiphilic P (C and D) model compounds by SPE method, which plots the absorption intensity against the retention time.

[0019] Figure 2 Shows the bleaching results of lipophilic (A and B) and amphiphilic (C and D) model compounds.

[0020] Figure 3 Shows the separation results of SPE of used cooking oil (UCO) samples.

[0021] Figure 4 and Figure 5 Provides a schematic representation of an embodiment of the general method. DETAILED DESCRIPTION

[0022] In the following description, like reference symbols denote like elements or steps. Unless otherwise specified, all standards cited herein are the latest revised versions available at the filing date.

[0023] When referring to phosphorus (P) generally in context, it is to be understood as encompassing any compound containing at least one phosphorus atom. Regarding analyses such as total phosphorus content, it is expressed and calculated as elemental phosphorus. However, it should be understood that in the feedstock, phosphorus is combined with inorganic and organic compounds, and its structure and properties depend on the type and source of the feedstock. Standard methods for determining the total phosphorus content in a sample are known. For oil or fat samples, an example of such a method is an inductively coupled plasma (ICP)-based determination, an example of which is ISO 10540-3:2002.

[0024] Lipophilic phosphorus compounds (i.e., P compounds that are difficult to remove) are herein referred to as phosphorus-containing impurities that cannot be effectively removed or can only be slightly removed in conventional surface chemical treatments such as degumming or bleaching. Even increasing the adsorbent dosage or performing multiple bleaching steps in sequence cannot improve the purification to the required level.

[0025] Without being bound by any theory, it is expected that P that is difficult to remove at the molecular level is likely formed from different precursor molecules via different pathways, which means that the difficult-to-remove P can encompass a range of phosphorus-containing molecules that are difficult to remove. Lipophilic phosphorus can have various origins and can also be, for example, added lipophilic phosphorus chemicals. Structurally, it is believed that the difficult-to-remove P is lipophilic, i.e., it prefers to stay in the lipid phase rather than enter the aqueous phase or settle at the phase interface. Lipophilic phosphorus impurities may be chemically formed or transformed from the original amphiphilic compounds by losing the polar head group, or they may be masked by structures with non-polar organic properties. By losing the amphiphilic nature of the molecule, it no longer has surface activity and will not be susceptible to removal by surface phenomena such as micelle / micelle formation in degumming or adsorption in bleaching, and thus cannot be removed by methods based on surface phenomena.

[0026] By definition, "lipophilic phosphorus compounds" are herein referred to as phosphorus derivatives that stay in the oil phase in an immiscible oil-water system or an adsorbent-oil system. The lipophilic phosphorus compounds generally do not exhibit interfacial surface activity towards the oil phase interface under the conditions of typical industrial degumming or bleaching processes.

[0027] When quantitatively evaluated, in a material stream such as a feedstock or a pretreated feedstock, the amount of lipophilic phosphorus compounds can be expressed and calculated as elemental phosphorus / total sample weight or volume, such as the lipophilic fraction collected by SPE. Although it is understood that there are different compounds, the identification of the compounds or the knowledge of their respective amounts is secondary to the need to determine the total amount of all lipophilic phosphorus compounds present. Thus, when referring to the amount of lipophilic phosphorus compounds, it refers to the total amount. For some purposes, it may be relevant to evaluate the difference between treated and untreated samples and / or the ratio between the content of lipophilic phosphorus compounds and the total phosphorus content.

[0028] In the experiments conducted, the solid-phase extraction method provided at least one lipophilic fraction and at least one amphiphilic fraction, each containing phosphorus compounds, which confirmed the difference between phosphorus compounds having both lipophilic and hydrophilic moieties, in contrast to lipophilic phosphorus compounds lacking a hydrophilic head. Among them, the lipophilic phosphorus compounds were only recovered in the lipophilic fraction and not in the amphiphilic fraction. Thus, the analysis of the lipophilic fraction provided qualitative and quantitative information about the lipophilic phosphorus compounds in the feed under discussion. Similarly, for example, the analysis before and after pretreatment can provide information about the effect of the pretreatment.

[0029] Generally, the feedstock used herein refers to renewable feedstock, i.e., feedstock from raw materials of biological origin. There are many sources of renewable feedstock, including oils and / or fats, which usually contain lipids (such as fatty acids or glycerides), such as vegetable oils / fats, vegetable oils / fats, animal oils / fats, algal oils / fats, fish oils / fats and algal oils / fats, or oils / fats from other microbial processes, such as genetically engineered algal oils / fats, genetically engineered oils / fats from other microbial processes, and also genetically engineered vegetable oils / fats. Components derived from these materials can also be used, such as alkyl esters, usually C1-C5 alkyl esters, such as methyl, ethyl, propyl, isopropyl, butyl, sec-butyl esters, or olefins. In addition, the renewable feedstock can include C1-C5 alkyl alcohols, especially methyl, ethyl, propyl, isopropyl, butyl and / or sec-butyl esters of fatty acids, and any combination thereof.

[0030] The renewable feedstock can additionally include free fatty acids, fatty acid esters (including monoglycerides, diglycerides and triglycerides) or combinations thereof. For example, the free fatty acids can include free fatty acids obtained by stripping free fatty acids from transesterified feedstock of triglycerides. The renewable feedstock can include fatty acid distillates from vegetable oil deodorization.

[0031] Vegetable and / or vegetable oils and / or microbial oils can include babassu oil, carinata oil, soybean oil, canola oil, coconut oil, rapeseed oil, crude tall oil (CTO), tall oil (TO), tall oil fatty acids (TOFA), tall oil pitch (TOP), palm oil (PO), palm fatty acid distillate (PFAD), jatropha oil, palm kernel oil, sunflower oil, castor oil, camelina oil, archaeal oil, bacterial oil, fungal oil, protozoal oil, algal oil, seaweed oil, oil from halophiles, and mixtures of any two or more thereof. Animal fats and / or oils can include inedible tallow, edible tallow, technical tallow, flotation tallow, lard, poultry fat, poultry oil, fish fat, fish oil, and mixtures of any two or more thereof. Greases can include yellow grease, brown grease, waste vegetable oil, restaurant grease, trap grease from municipalities (e.g., water treatment facilities), and waste oil from industrial packaged food operations, and mixtures of any two or more thereof. In the context of the present disclosure, feedstocks are generally of low quality and contain various impurities such as waste and residues, materials not suitable for food, feed, or cosmetic applications.

[0032] According to one embodiment, renewable feedstocks include at least one of the following: acidulated soapstock (ASK), poultry fat, dry rendered poultry fat (AFP), brown grease (BG), used cooking oil (UCO), tall oil, fractions of tall oil, crude tall oil (CTO), tall oil pitch (TOP), palm oil mill effluent (POME), crude palm oil (CPO), palm oil, palm seed oil, palm fatty acid distillate (PFAD), babassu oil, carinata oil, coconut butter, butter oil, sesame oil, corn oil, poppy seed oil, cottonseed oil, soybean oil, laurel oil, jatropha oil, palm kernel oil, camelina oil, archaeal oil, bacterial oil, fungal oil, protozoal oil, algal oil, seaweed oil, mustard seed oil, oil from halophiles, soybean oil (SBO), industrial corn oil, rapeseed oil (RSO), rapeseed oil, canola oil, sunflower oil, hempseed oil, olive oil, linseed oil, mustard oil, peanut oil, castor oil, coconut oil, lard, tallow, whale oil, spent bleaching earth oil (SBEO), lignocellulosic-based feed or any mixture thereof.

[0033] Among these feeds, some phosphorus compounds have proven difficult to remove using conventional purification methods based on surface chemistry, thus posing additional challenges. The waste and residual materials actually contain a variety of lipophilic phosphorus compounds. Animal fats as specific feedstocks contain, for example, membrane residues, which have proven difficult to remove from the feedstock stream.

[0034] The main sources of phosphorus in bio-oils are phospholipids and inorganic phosphates, especially in animal fats where they originate from bone meal. In addition, small amounts of phosphorus impurities from other sources (such as DNA, RNA, and ATP) may also be present, and further processing of the fat or oil may promote the formation of different types of organic phosphorus compounds, whose identities are not yet clear and which are difficult to remove by degumming or bleaching. Phospholipids are generally removed by degumming, and further residual phospholipids can be adsorbed in the adsorption step during bleaching (the degumming mechanism is also involved in many bleaching sequences). Heat treatment has been found to be very effective in degrading phospholipids (heat-sensitive), enabling their removal by filtration or bleaching. The phosphates in bone meal usually exist as solid particles and can be removed by filtration, for example, during bleaching.

[0035] Bio-origin oils and / or fats can include a single type of oil, a single type of fat, a mixture of different oils, a mixture of different fats, a mixture of oil and fat, fatty acids, glycerol, and / or a mixture of the foregoing substances. Generally, when using waste and residual materials, they contain a mixture of multiple components and thus contain various different lipophilic phosphorus compounds as impurities.

[0036] Fats, oils, and greases used as feedstocks may also contain other impurities, such as metals, mainly sodium, potassium, magnesium, calcium, iron, copper, or combinations thereof. Common pre-treatments based on surface chemistry are usually able to reduce the amount of metal impurities. The feed may further contain various heteroatoms, such as Cl, S, and N, in varying amounts, sometimes even in large quantities, depending on the origin of the feed. Heteroatoms can generally also be treated by available pre-treatment methods or treatment sequences.

[0037] A typical method of treating undesirable impurities (such as phosphorus impurities) in the feedstock is to pre-treat the feedstock before hydrotreating. Water-soluble phosphorus compounds, such as inorganic phosphorus or amphiphilic phosphorus, can be simply removed by degumming. However, in some animal fats, a significant portion of the phosphorus compounds are lipophilic phosphorus compounds, and they are far more difficult to reduce or remove compared to water-soluble or amphiphilic phosphorus compounds.

[0038] In the context of the present disclosure, hydrotreating is regarded as the "main process" for converting the feedstock into a product. Therefore, the treatment of renewable feedstocks, especially to reduce the lipophilic phosphorus content, is referred to herein as pre-treatment.

[0039] Hydrotreating refers to hydrodeoxygenation, hydrodesulfurization, hydrodenitrogenation, hydrodehalogenation (such as hydrodechlorination), hydrogenation of double bonds, hydrocracking, hydroisomerization, any combination thereof, and it also removes some metals. According to one embodiment, catalytic hydrotreating comprises one or more of hydrodeoxygenation, hydroisomerization, and hydrocracking, carried out simultaneously or sequentially. Generally, even if the main reaction is one of the above, other reactions occur as side reactions. Thus, some decarboxylation reactions and / or decarbonylation reactions may also occur. When aiming at fuel and / or biochemical production, typical sequences of hydrotreating reactions are hydroisomerization after hydrodeoxygenation, hydrocracking and hydroisomerization after hydrodeoxygenation, or hydroisomerization and hydrocracking after hydrodeoxygenation.

[0040] According to one embodiment, the pretreated renewable feedstock is hydrotreated in the presence of a catalyst selected from Pd, Pt, Ni, Co, Mo, Ru, Rh, W, or any combination thereof, such as CoMo, NiMo, NiW, CoNiMo, NiMoW or together with SAPO-11, SAPO-41, ZSM-22, ZSM-23, ZSM-12, ZSM-48, ZSM-5, beta zeolite, ferrierite and mixtures thereof, such as Pt / SAPO-11 / Al2O3, Pt / ZSM-22 / Al2O3, Pt / ZSM-23 / Al2O3, Pt / SAPO-11 / SiO2, optionally on a support, where the support is preferably alumina and / or silica, and a liquid product comprising renewable hydrocarbons is recovered. If a phosphoric acid compound (such as a salt) forms and precipitates thereon, the catalyst will lose its activity. Thus, removing the lipophilic phosphorus compound helps to extend the catalyst life.

[0041] Avoiding catalyst deactivation (i.e., the loss of catalytic activity and / or selectivity over time) is an ongoing goal in industrial catalytic processes. The industrial costs of catalyst replacement and process downtime add up to a significant economic loss annually. The time scale of catalyst deactivation can vary widely depending on the process and the type of catalyst used. Some catalysts last for a few seconds, while some may last for decades. Nevertheless, all catalysts will eventually deactivate, which is inevitable. Generally, in a well-controlled process, the loss of activity and / or selectivity occurs slowly. However, process anomalies or poor hardware design may lead to unexpected early failures. Although catalyst deactivation is inevitable for most processes, some of its severe consequences can be avoided or at least postponed by the present methods and uses.

[0042] Catalyst deactivation, as referred to in this text, means the gradual deterioration of the catalyst's performance, which ultimately reaches a level where it is no longer reasonable to continue using the catalyst. In this context, reasonableness is best described as the ability to produce products that meet the predetermined quality and quantity standards. In fact, this means that every catalyst will reach a point in time when it is deactivated to the extent that the spent catalyst needs to be replaced with a new one. Therefore, deactivation can be described as the length of the catalyst's life for each shutdown frequency. Considering the shutdowns required for catalyst replacement due to deactivation, this ratio provides a measure of the ability to produce the final product. In other words, if there are fewer shutdowns due to catalyst replacement caused by catalyst deactivation, the production loss within a given time range will be less.

[0043] Catalyst deactivation is usually defined as impurities remaining on the catalyst surface, thereby blocking the active sites of the catalyst from the feed molecules. Catalyst deactivation may be caused by catalyst fouling or poisoning. Fouling is generally considered to be related to the deposition of insoluble components present in the feed, or formed by the degradation of the feed or reaction intermediates, while poisoning is related to the deposition of electropositive pollutants (such as alkali metals and alkaline earth metals) on the acidic sites or the deposition of electronegative pollutants on the hydrogenation sites.

[0044] Hydrodeoxygenation is preferably the first catalytic hydrogenation treatment in the hydrotreating sequence and is carried out in the presence of a hydrodeoxygenation catalyst on a support selected from Pd, Pt, Ni, Co, Mo, Ru, Rh, W or any combination thereof, such as CoMo, NiMo, NiW, CoNiMo, where the support is preferably alumina and / or silica.

[0045] Hydrodeoxygenation can be carried out under reaction conditions including a temperature in the range of 100 to 500 °C, preferably 250 to 400 °C, more preferably 280 - 350 °C, and most preferably 300 - 330 °C.

[0046] Hydrodeoxygenation can be carried out under reaction conditions including a pressure in the range of 0.1 to 20 MPa, preferably 0.2 to 8 MPa.

[0047] Preferably, the weight hourly space velocity (WHSV) in the hydrodeoxygenation reaction is in the range of 0.5 to 3.0 h-1, more preferably 1.0 to 2.5 h-1, and most preferably 1.0 to 2.0 h-1. Preferably, the H2 flow is in the range of 350 to 900 nl H2 / l of feed, more preferably 350 to 750, and most preferably 350 to 500, where nl H2 / l refers to the normal liters of hydrogen per liter of feed entering the HDO reactor in the presence of the hydrodeoxygenation catalyst.

[0048] Hydroprocessing can include hydrodeoxygenation and hydroisomerization carried out simultaneously or sequentially. In one specific embodiment, a NiW catalyst is used to carry out hydrodeoxygenation and hydroisomerization simultaneously.

[0049] When HDO is first carried out on the pretreated feedstock, according to a preferred hydroprocessing sequence, the liquid product recovered therefrom is then subjected to hydroisomerization to produce branched alkanes. The hydroisomerization is carried out in the presence of a hydroisomerization catalyst comprising a support, a metal, and other catalyst materials, the support being selected from Al2O3 and SiO2, and the metal being selected from Pt, Pd, and Ni, and the other catalyst materials being selected from SAPO-11, SAPO-41, ZSM-22, ZSM-23, ZSM-12, ZSM-48, ZSM-5, beta zeolite, and mixtures thereof. It has been found that such catalyst materials can be deactivated if lipophilic phosphorus compounds cannot be effectively removed, and the pretreatment according to the present invention can at least partially prevent such deactivation.

[0050] The hydroisomerization step is preferably carried out at a temperature of 250 to 400 °C, more preferably 280 to 370 °C, and most preferably 300 to 350 °C.

[0051] The hydroisomerization can be carried out under reaction conditions comprising a pressure preferably of 1 to 6 MPa, more preferably 2 to 5 MPa, and most preferably 2.5 to 4.5 MPa.

[0052] The hydrodeoxygenation can be carried out under reaction conditions comprising: the WHSV is preferably 0.5 to 3 h-1, more preferably 0.5 to 2 h-1, and most preferably 0.5 to 1 h-1, and the H2 flow (in units of: liters of H2 / liter of feed) is preferably 100 to 800, more preferably 200 to 650, and most preferably 350 to 500.

[0053] The isomerization treatment is a step mainly used to isomerize at least part of the hydrodeoxygenated raw material. That is to say, although most thermal conversions or catalytic conversions (such as HDO) will result in a small degree of isomerization (usually less than 5 wt-%), the isomerization step will result in a significant increase in the content of iso-paraffins.

[0054] Some cracking may occur in a conventional hydroisomerization process. Therefore, the selection of the catalyst and the optimization of the reaction conditions are always important during the isomerization step. Due to the cracking during the isomerization process, renewable diesel and renewable aviation fuel components may be formed.

[0055] The hydroisomerization can be carried out in a conventional hydroisomerization unit. Hydrogen is added in the hydroisomerization step. The hydrodeoxygenation step and the hydroisomerization step can be carried out in different reactor beds or even in the same reactor bed in the same reactor.

[0056] As a product, preferably as a liquid product, the hydrotreatment of the starting materials of the present invention provides various hydrocarbons, preferably alkanes, more preferably at least partly isoparaffins, suitable for use in fuel applications. According to one embodiment, the renewable hydrocarbons suitable for use in fuel applications comprise components for renewable diesel, sustainable aviation fuel, renewable gasoline or any combination thereof, preferably at least one or more of the renewable diesel components meeting the requirements of EN15490-2018 and the sustainable aviation fuel components meeting the requirements of Annex 2 of ASTM D7566-2020.

[0057] Chemically, the renewable or fossil origin of any organic compound (including hydrocarbons) can be determined by methods suitable for analyzing the carbon content from renewable sources, such as DIN 51637 (2014), ASTM D6866 (2020), or EN 16640 (2017). The methods are based on the fact that carbon atoms of renewable or biological origin contain a higher number of unstable radiocarbon (14C) atoms compared to carbon atoms of fossil origin. The 14C isotope content can be used as evidence of the renewable or biological origin of starting materials, any intermediates or products. Thus, by analyzing the ratio of 12C and 14C isotopes, carbon compounds derived from biological sources can be distinguished from those derived from fossil sources. Thus, a specific ratio of said isotopes can be used to identify renewable carbon compounds and distinguish them from non-renewable compounds (i.e., fossil carbon compounds). The isotope ratio does not change during a chemical reaction. An example of a suitable method for analyzing the carbon content from biological sources is ASTM D6866 (2020). For example, an example of how to apply ASTM D6866 to determine the renewable content in fuels is provided in the article by Dijs et al., Radiocarbon, 48(3), 2006, pp 315-323. For the purposes of the present invention, a carbon-containing material (such as a starting material or product) is considered to be of renewable origin if it contains 90% or more modern carbon (pMC), such as about 100% modern carbon, when measured using ASTM D6866.

[0058] According to a first aspect, there is provided herein a method for producing renewable hydrocarbons suitable for use in fuel applications from a renewable starting material comprising at least one or more lipophilic phosphorus compounds, the method comprising the following steps:

[0059] (i) providing a renewable starting material, wherein the total amount of lipophilic phosphorus compounds calculated as elemental phosphorus is greater than 2 wppm but less than 50 wppm of the total starting material weight;

[0060] (ii) performing at least one pretreatment on the renewable raw material to obtain a pretreated renewable raw material, wherein the total amount of the lipophilic phosphorus compound calculated as elemental phosphorus is lower than the total amount of the lipophilic phosphorus compound of the renewable raw material in step (i), preferably less than 2 wppm of the weight of the pretreated raw material, preferably less than 1.5 ppm, such as 1.5 to 0.1 wppm;

[0061] (iii) performing at least one catalytic hydrotreating step on the pretreated renewable raw material to obtain renewable hydrocarbons.

[0062] The inventors have found that the amount of at least one or more lipophilic phosphorus compounds provides an excellent indicator of the ability of conventional pretreatment methods to remove phosphorus from raw materials. And it is an important indicator of the quality of the raw material. Additionally, it also indicates whether the raw material is safe and ready to be fed to a hydrotreating catalyst, or whether pretreatment is required to reduce the content of the lipophilic phosphorus compound, in other words, suitable to be directed to hydrotreating without excessive deactivation of the catalyst and / or shortening the life of the HDO catalyst, provided that the total P content is at a reasonable level.

[0063] Regarding the total amount of lipophilic phosphorus compounds in the renewable raw material, the present invention has demonstrated that when the total amount of the lipophilic phosphorus compound calculated as elemental phosphorus is greater than 1 wppm of the total renewable raw material weight (but usually greater than 2 wppm, such as 2 wppm to 50 wppm), it provides the best results in reducing catalyst deactivating compounds. It should be understood that in the case where the total amount of the lipophilic phosphorus compound calculated as elemental phosphorus is only slightly greater than 1 wppm (such as 1 to 2 wppm), the total amount of the lipophilic phosphorus compound in the pretreated renewable raw material is lower than the total amount of the lipophilic phosphorus compound of the renewable raw material in step (i), and then preferably lower than 1 wppm of the weight of the pretreated raw material, such as 1 to 0.1 wppm. The quality of the renewable raw material with the total amount of the lipophilic phosphorus compound calculated as elemental phosphorus exceeding 50 wppm is very low and is thus not suitable for this method or requires more onerous treatment for purification.

[0064] Generally, one pretreatment is sufficient when selected based on the information on the lipophilic phosphorus compound content therein. However, according to one embodiment, two or more raw material pretreatments are carried out sequentially in step (ii). A combination of two or more pretreatments may be required in cases where the amount of the lipophilic phosphorus compound in the renewable raw material before any treatment is extremely high, or the lipophilic phosphorus compound contains multiple compound types with different responses to pretreatment.

[0065] In step (ii), the total amount of lipophilic phosphorus compounds calculated as elemental phosphorus in the pretreated renewable raw material is lower than the total amount of lipophilic phosphorus compounds in the renewable raw material in step (i). Preferably, in the pretreated renewable raw material, the total amount of lipophilic phosphorus compounds calculated as elemental phosphorus is less than 2 wppm of the weight of the pretreated renewable raw material, preferably less than 1.5 wppm, such as 1.5 to 0.1 wppm. Feeds with a total amount of lipophilic phosphorus compounds greater than 2 wppm will destroy the catalyst activity within a few months, resulting in costly downtime and requiring catalyst regeneration. This experiment has demonstrated that by subjecting various animal fat samples to a pretreatment sequence of heat treatment followed by bleaching, a very low total amount of lipophilic phosphorus compounds can be obtained, such as less than 2 wppm (Example 4), where the total amount of lipophilic phosphorus compounds in the raw material initially generally ranges from about 5 to about 25 wppm.

[0066] For the raw materials of the present invention, a variety of pretreatments with various modifications in the art itself are available. According to a preferred embodiment, the raw material pretreatment or multiple pretreatments are selected from degumming, heat treatment, high temperature adsorption (HTA), acid treatment, filtration, bleaching, blending, or any combination thereof. The method of the present invention that selects the pretreatment based on determining the amount of lipophilic phosphorus compounds can optimally protect the hydrotreating catalyst from deactivation and extend the catalyst life. Also, over-pretreatment can be prevented, which inevitably leads to an increase in processing costs and a loss in yield. The choice of pretreatment depends on, for example, the raw material composition, impurity profile, and the amount of impurities present. For example, for a specific raw material, it has been found that heat treatment can effectively remove lipophilic phosphorus compounds from the raw material, but in some other cases, if the analysis shows that only a small fraction of the total phosphorus content is lipophilic phosphorus, heat treatment may be redundant. Therefore, performing only the necessary pretreatment results in a more efficient and economical process.

[0067] In one embodiment, the pretreatment is selected from heat treatment, optionally followed by evaporation of volatiles, wherein the raw material is heated at a temperature of 80 °C to 325 °C, preferably 180 °C to 300 °C, more preferably 200 °C to 280 °C for a residence time of 1 to 300 min. The heat treatment can be followed by an evaporation step, wherein in particular silicon-containing compounds are removed. Examples of heat treatment of raw materials containing organic materials can be found in WO 2020 / 016405. Filtration can also be performed after the heat treatment, either as a supplement or alternative to evaporation. When the raw material contains brown grease or acidulated soapstock, a pretreatment comprising heat treatment with or without a filter aid (adsorbent) can be used, followed by filtration and possibly bleaching.

[0068] In one embodiment, the pretreatment is selected from heat treatment with an adsorbent (HTA), optionally followed by flash evaporation. When the feedstock includes CTO and / or TOP, HTA is particularly applicable as a pretreatment, but is also suitable for another feedstock. Heat treatment with an adsorbent (HTA) can be carried out at a temperature of 180 °C to 325 °C, preferably 200 °C to 300 °C, more preferably 240 °C to 280 °C, optionally in the presence of an acid. The adsorbent can be selected from aluminosilicate, silica gel, and mixtures thereof, and is generally added in an amount of 0.1 wt.% to 10 wt.%, such as 0.5 wt.%. Examples of HTA can be found in WO 2020 / 016410. Heat treatment with an adsorbent (HTA) can also be referred to as high-temperature adsorption, heat treatment with adsorption, or heat treatment in the presence of an adsorbent.

[0069] In one embodiment, the pretreatment is selected from bleaching. Bleaching can be carried out by adding an acid in an amount of 500 to 5000 ppm based on the feedstock. The bleaching treatment can be carried out at a temperature of 60 °C to 90 °C and includes a drying step at 110 °C to 130 °C under reduced pressure. Bleaching is completed by a filtration step to remove the formed solids and possible adsorbents and filter aids. In one example, bleaching includes the following sequence:

[0070] (1) Add acid, 1000 - 4000 ppm citric acid (50% aqueous solution), 85 °C, 10 min;

[0071] (2) Add adsorbent / filter aid, 0.1 - 1 wt.%, 85 °C, 800 mbar, 20 min;

[0072] (3) Dry, 120 °C, 80 mbar, 25 min;

[0073] (4) Filter, 120 °C, 2.5 bar.

[0074] Both heat treatment (HT) and heat treatment with an adsorbent (HTA) can be carried out under pressure, which can be 10 to 5000 kPa, or such as 150 to 800 kPa. In addition, water can be added up to a level of 5 wt.%, such as 1 wt.% - 3 wt.%, before or during HT and HTA. Evaporation (e.g., carried out by flash evaporation) can be carried out after HT or HTA or any other pretreatment stage and can be carried out at a pressure of 10 to 100 mbar (1 to 10 kPa) at about 160 °C (such as 150 °C to 225 °C).

[0075] For a feedstock containing palm oil mill effluent sludge (POME), the pretreatment can include acid degumming, followed by removal of solids from the liquid using filtration or centrifugation. A bleaching step can be further carried out after the degumming process.

[0076] In one embodiment of the present invention, the pretreatment includes heat treatment (HT), followed by bleaching.

[0077] In one embodiment of the present invention, the pretreatment includes heat treatment (HT) with addition of an alkali and bleaching.

[0078] In one embodiment of the present invention, the pretreatment includes heat treatment with an adsorbent (HTA), followed by bleaching, or optionally followed by flash evaporation (removing light components including Si components etc. by evaporation) and bleaching.

[0079] Furthermore, the pretreatment may or may not include additional steps such as removing solids (using techniques such as centrifugation or filtration) before and / or after HT or HTA, water washing, degumming, hydrolysis, distillation, strong acid treatment, second or further bleaching, or any combination of the above methods.

[0080] In a preferred embodiment, bleaching is the last step of the pretreatment sequence. Bleaching can be regarded as a polishing treatment to prepare the pretreated feedstock for the hydrotreating step. However, a single bleaching cannot remove the high impurity level of a very dirty feedstock.

[0081] In one embodiment of the present invention, the pretreatment includes blending the feedstock with a second feedstock having a total amount of lipophilic phosphorus compounds lower than that of the feedstock to be treated. Blending is considered most beneficial if carried out early in the pretreatment sequence, but it can be carried out at any stage. In order to be able to calculate the appropriate blending ratio, it is necessary to analyze the total amounts of lipophilic phosphorus compounds in the feedstock to be treated and the second feedstock. Analyzing the total phosphorus content is not sufficient.

[0082] According to a specific embodiment, the combination of the pretreatment consists of a combination of blending and heat treatment, preferably in the said order. However, in cases where the heat treatment capacity limits the total process volume, it may be beneficial to combine the heat treatment and blending in this order. In experiments on the analysis of lipophilic phosphorus compounds and with some pretreatment methods, the heat treatment provided promising results.

[0083] According to another specific embodiment, the combination of the pretreatment consists of a combination of heat treatment with an adsorbent and blending, preferably in the said order. However, in cases where the processing capacity is limited, it may be beneficial to combine the heat treatment with an adsorbent and blending in this order.

[0084] According to one embodiment, at least one pretreatment step is selected based on data regarding the ability of a pretreatment to reduce the total amount of lipophilic phosphorus compounds in a feedstock; and at least one such selected pretreatment is performed on a renewable feedstock. The data on which the pretreatment selection is based can be obtained from experiments or full-scale runs that have analyzed lipophilic phosphorus compounds, such as from the feedstock and the pretreated feedstock.

[0085] For this experiment, an analytical method was developed. It was found that instead of or subsequent to analyzing the total phosphorus content, a dedicated analysis of the lipophilic fraction provides the most relevant information for pretreatment selection. Thus, according to one embodiment, determining the total amount of lipophilic phosphorus compounds is carried out by an analysis that includes: separating at least one fraction containing lipophilic phosphorus compounds, and analyzing the fraction to provide data on the total amount of lipophilic phosphorus compounds in the renewable feedstock or the pretreated renewable feedstock. In practice, the analysis is typically performed on samples collected from the feedstock, the pretreated feedstock, any intermediate between the pretreatments, and / or a combination thereof. However, collecting samples can be replaced by any means that provides the corresponding analysis results, such as microchips and the like.

[0086] Subsequent to the fraction containing lipophilic phosphorus compounds, preferably, the analysis includes collecting at least one amphiphilic fraction. Collecting these two fractions with an appropriate solvent system facilitates more specific analysis.

[0087] According to one embodiment, the separation includes solid-phase extraction (SPE) or flash chromatography. In this experiment, SPE was proven to be effective.

[0088] According to one embodiment, SPE includes using a solvent system, preferably a set of solvents with increasing solvent polarity in the solvent system for extraction.

[0089] According to one embodiment, the phosphorus content in the separated fraction is analyzed by quantitative mass spectrometry (preferably inductively coupled plasma mass spectrometry (ICP-MS coupled)).

[0090] As a second aspect, the present invention describes the use of separating and analyzing to provide data on at least one lipophilic phosphorus compound in a renewable feedstock in the catalytic production of renewable hydrocarbons, the use further including, based on the separation and analysis, selecting a pretreatment capable of reducing the content of lipophilic phosphorus compounds, and performing the selected pretreatment on the renewable feedstock to provide a pretreated renewable feedstock.

[0091] According to one embodiment, the total amount of lipophilic phosphorus compounds calculated as elemental phosphorus is lower than the total amount of lipophilic phosphorus compounds in the renewable feedstock, preferably less than 2 wppm of the weight of the pretreated renewable feedstock, more preferably less than 1.5 wppm, such as from 1.5 wppm to 0.1 wppm.

[0092] According to one embodiment, the separation and analysis comprises the following steps:

[0093] (a) Collecting at least one sample of the renewable raw material containing the lipophilic phosphorus compound;

[0094] (b) Separating at least one fraction containing the lipophilic phosphorus compound from the sample; and

[0095] (c) Analyzing the fraction to provide data on the total amount of lipophilic phosphorus compound in the renewable raw material.

[0096] According to one embodiment, the separation in step (b) comprises solid phase extraction (SPE) or flash chromatography, preferably SPE.

[0097] According to one embodiment, the use further comprises subjecting the pretreated renewable raw material to at least one catalytic hydrotreating to obtain renewable hydrocarbons.

[0098] According to one embodiment, the separation and the analysis for providing data on at least one lipophilic phosphorus compound in the renewable raw material in the catalytic production of renewable hydrocarbons is used to reduce the loss of hydrotreating catalyst activity.

[0099] Figure 4 and 5

[0100] Next, reference is made to the appended Figure 4 and 5 The method and use of the present invention are described in the form of a schematic system for preparing or manufacturing hydrocarbons. Figure 4 An exemplary embodiment of the system 400 is shown, and Figure 5Another exemplary embodiment is shown. As can be appreciated from the figures, system 400 can include at least one container 401 for storing a renewable feedstock containing a lipophilic phosphorus compound. The system can also include at least one sample extraction mechanism 403 configured to extract a feedstock sample before the renewable feedstock is received or fed into at least one pretreatment device 402 and / or a hydrotreating reactor system 404. Further samples can be taken before or after any pretreatment device 402 and / or before the hydrotreating reactor system 404. The feedstock from one or more containers 401 can be fed into at least one pretreatment device 402 for pretreatment before being fed into the hydrotreating reactor system 404. The hydrotreating reactor system 404 can be positioned to receive the pretreated renewable feedstock from any pretreatment device 402 such that the renewable feedstock fed into the hydrotreating reactor system 404 can undergo a hydrotreating process to form hydrocarbons in at least one catalytic reaction employing a catalyst. The hydrotreating reactor system 404 can include at least one catalyst bed in at least one reactor, but can include multiple catalyst beds having the same or different hydrotreating activities in the same or different reactors.

[0101] The content of the lipophilic phosphorus compound in the pretreated renewable feedstock that can undergo the hydrotreating process can be in the range of less than or equal to 2 parts per million by weight (wppm), thereby reducing or avoiding catalyst deactivation. Each sample extraction mechanism 403 can be configured to extract a feedstock sample for analysis. The analysis performed can identify various aspects of P impurities within the feedstock in order to select which pretreatment device 402 to use for the feedstock to pretreat the feedstock and then feed the feedstock into the hydrotreating reactor system 404 to form hydrocarbons. The selected pretreatment device 402 can include at least one pretreatment device 402 located between the container 401 and the hydrotreating reactor system 404 to pretreat the renewable feedstock in the container via at least one pretreatment process, thereby reducing the content of the lipophilic phosphorus compound within the renewable feedstock before transferring the renewable feedstock to the hydrotreating reactor system 404.

[0102] For example, the selected pretreatment process may include degumming and / or heat treatment followed by bleaching, applying only heat treatment, applying only degumming and / or bleaching, blending multiple feedstocks from multiple containers prior to further pretreatment via another pretreatment device 402, or other suitable pretreatment processes for effectively reducing the P content to within a preselected P content range as discussed herein. For example, at least one pretreatment device 402 may be configured to perform one or more of the following: degumming, heat treatment, heat treatment using an adsorbent (HTA), acid treatment, filtration, bleaching, bleaching using an adsorbent, and / or blending. Embodiments of system 400 may be configured to utilize a method for producing renewable hydrocarbons suitable for use in fuel applications from renewable feedstocks comprising at least one or more lipophilic phosphorus compounds.

[0103] Embodiments of the present invention are presented below in numbered items.

[0104] 1. A method for preparing hydrocarbons, the method comprising:

[0105] Subjecting a renewable feedstock comprising a lipophilic phosphorus compound to a hydrotreating process to form hydrocarbons from the renewable feedstock;

[0106] wherein the content of the lipophilic phosphorus compound in the renewable feedstock is in the range of less than 2 parts per million by weight (wppm) and 0.1 wppm, such that deactivation of the catalyst used in the hydrotreating process is reduced or avoided.

[0107] 2. The method of item 1, comprising:

[0108] Evaluating the renewable feedstock to determine the content of the lipophilic phosphorus compound in the renewable feedstock prior to subjecting the renewable feedstock to the hydrotreating process; and

[0109] In response to determining that the content of the lipophilic phosphorus compound in the renewable feedstock is greater than a preselected lipophilic phosphorus content threshold, pretreating the renewable feedstock via at least one pretreatment process to reduce the content of the lipophilic phosphorus compound in the renewable feedstock such that the content of the lipophilic phosphorus compound in the renewable feedstock is less than 2 wppm and greater than or equal to 0.1 wppm or less than 1.5 wppm and greater than or equal to 0.1 wppm.

[0110] 3. The method of item 2, wherein the at least one pretreatment process comprises degumming, heat treatment, acid treatment, filtration, bleaching, heat treatment using an adsorbent (HTA), blending, or any combination thereof.

[0111] 4. The method of item 1, wherein the renewable feedstock is a first renewable feedstock, the method comprising:

[0112] Before subjecting a first renewable feedstock to a hydrotreating process, a second renewable feedstock is evaluated to determine the content of lipophilic phosphorus compounds in the second renewable feedstock;

[0113] In response to determining that the content of lipophilic phosphorus compounds in the second renewable feedstock is greater than a preselected lipophilic phosphorus content threshold, at least one of the following is performed:

[0114] Blend the second renewable feedstock with at least one third renewable feedstock to form a blended renewable feedstock such that the content of lipophilic phosphorus compounds in the blended renewable feedstock is lower than the content of lipophilic phosphorus compounds in the second renewable feedstock and is equal to or lower than the preselected lipophilic phosphorus content threshold; and / or

[0115] Pretreat the second renewable feedstock or the blended renewable feedstock to reduce the content of lipophilic phosphorus compounds therein;

[0116] wherein blending and / or pretreatment is performed to form a first renewable feedstock for subjecting the first renewable feedstock to a hydrotreating process.

[0117] 5. The method of item 1, comprising:

[0118] Analyze the content of lipophilic phosphorus compounds in the renewable feedstock.

[0119] 6. The method of item 5, wherein the analysis of the content of lipophilic phosphorus compounds in the renewable feedstock comprises:

[0120] Collect at least one sample of the renewable feedstock;

[0121] Isolate from the sample at least one fraction containing lipophilic phosphorus compounds, and

[0122] Analyze the at least one fraction to provide data on the content of lipophilic phosphorus compounds in the renewable feedstock.

[0123] 7. The method of item 6, wherein isolating from the sample at least one fraction containing lipophilic phosphorus compounds comprises solid phase extraction (SPE),

[0124] Performing the separation from the sample such that at least one amphiphilic fraction is also collected; and

[0125] SPE comprises using a solvent system such that the polarity of the solvent in the solvent system increases during SPE.

[0126] 8. The method of item 7, wherein the analysis of the at least one fraction containing lipophilic phosphorus compounds comprises at least one of the following:

[0127] Quantitative analysis to provide quantitative data on the lipophilic phosphorus compounds;

[0128] Quantitative mass spectrometry, and / or

[0129] Inductively coupled plasma mass spectrometry.

[0130] 9. The method of item 1, comprising:

[0131] Evaluating a renewable raw material prior to a hydrotreating process on the renewable raw material to determine the content of lipophilic phosphorus compounds in the renewable raw material; and

[0132] In response to determining that the content of lipophilic phosphorus compounds in the renewable raw material is greater than a preselected lipophilic phosphorus content threshold, selecting at least one pretreatment process to pretreat the renewable raw material to reduce the content of lipophilic phosphorus compounds in the renewable raw material such that the content of lipophilic phosphorus compounds in the renewable raw material is less than 2 wppm and greater than or equal to 0.1 wppm, the selection being based on the results from the evaluation of the renewable raw material.

[0133] 10. The method of item 1, wherein the hydrotreating process comprises one or more of hydrodeoxygenation, hydrodecarboxylation, hydrodecarbonylation, hydroisomerization, and hydrocracking.

[0134] 11. A system for preparing hydrocarbons, the system comprising:

[0135] A container for storing a renewable raw material containing lipophilic phosphorus compounds;

[0136] A hydrotreating reactor positioned to receive the renewable raw material from the container such that the renewable raw material fed to the hydrotreating reactor can undergo a hydrotreating process to form hydrocarbons in a catalytic reaction using a catalyst, the content of lipophilic phosphorus compounds in the renewable raw material that can undergo the hydrotreating process being in the range of less than 2 parts per million by weight (wppm) and greater than or equal to 0.1 wppm, such that deactivation of the catalyst is reduced or avoided.

[0137] 12. The system of item 11, comprising:

[0138] At least one pretreatment device positioned between the container and the hydrotreating reactor to pretreat the renewable raw material via at least one pretreatment process to reduce the content of lipophilic phosphorus compounds in the renewable raw material before the renewable raw material is delivered to the hydrotreating reactor.

[0139] 13. The system of item 12, wherein the at least one pretreatment device is configured to perform one or more of: degumming, heat treatment, acid treatment, filtration, bleaching, heat treatment with an adsorbent (HTA), and / or blending.

[0140] 14. A renewable raw material for undergoing a hydrotreating process to form hydrocarbons, comprising:

[0141] A renewable feedstock formed from at least one renewable source, the renewable feedstock comprising a lipophilic phosphorus compound, the content of the lipophilic phosphorus compound in the renewable feedstock being in the range of less than 2 parts per million by weight (wppm) and greater than or equal to 0.1 wppm, such that deactivation of a catalyst used in a hydrotreating process is reduced or avoided.

[0142] 15. The renewable feedstock of item 14, wherein the at least one renewable source comprises one or more of the following:

[0143] Rapeseed oil, canola oil, mustard oil, tall oil, sunflower oil, soybean oil, hempseed oil, cottonseed oil, corn oil, olive oil, linseed oil, mustard oil, palm oil, peanut oil, castor oil, coconut oil, camellia oil, jatropha oil, oils from microbial sources, animal fats, fish oils, lard, tallow, whale oil, oils from bacteria, oils from molds, oils from filamentous fungi, recycled fats from at least one industrial food source, and mixtures thereof.

[0144] 16. A method for selecting a renewable feedstock for use in forming hydrocarbons, the method comprising:

[0145] Before obtaining a renewable feedstock for use in a hydrotreating process to form hydrocarbons, evaluating the renewable feedstock to determine the content of lipophilic phosphorus compound in the renewable feedstock;

[0146] In response to a determination that the content of lipophilic phosphorus compound in the renewable feedstock is greater than a preselected lipophilic phosphorus content threshold, evaluating whether the renewable feedstock can be pretreated to reduce the content of lipophilic phosphorus compound in the renewable feedstock such that the content of lipophilic phosphorus compound in the renewable feedstock is in the range of less than 2 parts per million by weight (wppm) and greater than or equal to 0.1 wppm,

[0147] In response to a determination that the renewable feedstock can be pretreated to reduce the content of lipophilic phosphorus compound in the renewable feedstock to be in the range of less than 2 wppm and greater than or equal to 0.1 wppm, accepting or obtaining the renewable feedstock for use in a process for forming hydrocarbons.

[0148] 17. The method of item 16, comprising:

[0149] Pretreating the renewable feedstock via one or more of the following: degumming, heat treatment, acid treatment, filtration, bleaching, heat treatment with an adsorbent (HTA), blending, or any combination thereof.

[0150] 18. The method of item 16, wherein the evaluated renewable feedstock is a first renewable feedstock, and the method further comprises:

[0151] Before subjecting a first renewable feedstock to a hydrotreating process, a second renewable feedstock is evaluated to determine the content of lipophilic phosphorus compounds in the second renewable feedstock;

[0152] In response to determining that the content of lipophilic phosphorus compounds in the second renewable feedstock is less than a preselected lipophilic phosphorus compound content threshold, at least one of the following is performed:

[0153] The second renewable feedstock is blended with the first renewable feedstock to form a blended renewable feedstock such that the content of lipophilic phosphorus compounds in the blended renewable feedstock is lower than the content of lipophilic phosphorus compounds in the first renewable feedstock and the content of lipophilic phosphorus compounds in the blended renewable feedstock is equal to or lower than the preselected lipophilic phosphorus content threshold to form a hydrotreating feed for feeding to the hydrotreating process; or

[0154] The first renewable feedstock is pretreated to reduce the content of lipophilic phosphorus compounds therein and then blended with the second renewable feedstock to form a hydrotreating feed for feeding to the hydrotreating process, and the content of lipophilic phosphorus compounds in the hydrotreating feed is equal to or lower than the preselected lipophilic phosphorus content threshold.

[0155] 19. The method of item 18, wherein the pretreatment of the first renewable feedstock includes degumming, heat treatment, acid treatment, filtration, bleaching, heat treatment with an adsorbent (HTA), or any combination thereof.

[0156] 20. The method of item 16, wherein evaluating the renewable feedstock includes:

[0157] Analyzing the content of lipophilic phosphorus compounds in the renewable feedstock, the analysis including:

[0158] Collecting at least one sample of the renewable feedstock;

[0159] Isolating at least one fraction containing lipophilic phosphorus compounds from the sample, isolating at least one fraction containing lipophilic phosphorus compounds from the sample includes solid phase extraction (SPE), performing the separation from the sample so as to also collect at least one amphiphilic fraction, and the SPE includes using a solvent system such that the polarity of the solvent in the solvent system increases during the SPE process, and

[0160] Analyzing the at least one fraction to provide data on the content of lipophilic phosphorus compounds in the renewable feedstock, the analysis of the at least one fraction includes at least one of the following:

[0161] Quantitative analysis to provide quantitative data on the lipophilic phosphorus compounds;

[0162] Quantitative mass spectrometry, and / or

[0163] Inductively coupled plasma mass spectrometry.

[0164] Example

[0165] The following examples are provided to better illustrate the claimed invention. They should not be construed as limiting the scope of the invention, which is determined by the claims. The specific materials mentioned are for illustrative purposes only and are not intended to limit the invention. Those skilled in the art can develop equivalent methods or reactants without the use of creative faculty and without departing from the scope of the invention. It should be understood that many changes can be made to the procedures described herein while still remaining within the scope of the invention. All exemplary materials and parameters used in the following examples are compatible with the methods and products described herein.

[0166] This experiment describes a method for extracting and quantifying lipophilic P from renewable raw materials. An automated solid-phase extraction (SPE)-based method was developed for the CombiFlash NextGen 300+ system (Teledyne ISCO) equipped with four solvent inlets, an evaporative light scattering (ELS) and a UV-vis detector. It can be coupled with various types and sizes of commercial separation columns before detection.

[0167] In this disclosure, a 24 g gold-grade silica column was used as the stationary phase, and heptane, isopropanol, methanol, and their mixtures were used as solvents (mobile phases) to increase polarity for fractional extraction. The lipophilic and amphiphilic fractions can be determined based on the ELS detector, and their amounts can be quantified by weight after removing the solvents (by rotary evaporator). This method can be used to determine the lipophilic content in lipid-based raw materials and their pretreated products (such as bleached products, aged products).

[0168] Example 1: Identifying samples with high lipophilic phosphorus compound content:

[0169] The total phosphorus content of seven bio-oil samples was analyzed (e.g., using ICP-MS / MS, using samples microwave-degraded before analysis), and the content (total amount) of their lipophilic phosphorus compounds was further analyzed according to the disclosed SPE method (Example 5).

[0170] The results showed that most of these feeds contained 1 - 2 wppm of lipophilic phosphorus compounds, and the lipophilic phosphorus compounds generally accounted for <10% of the total P concentration. However, one brown grease sample was found to have a very high lipophilic phosphorus compound content (27 wppm, equivalent to 23% - wt of total P), which indicates a severe challenge for the feed purification of catalytic hydroprocessing and commonly used pretreatments such as degumming or bleaching. Brown grease is known to be a very challenging lipid feed category, and its interpretation related to phosphorus compounds was confirmed in this analysis and is shown in Table 1.

[0171] Table 1 gives the analysis results providing the total phosphorus content (P total (wppm)), the lipophilic phosphorus content (lipophilic P (wppm)), and the share of the lipophilic phosphorus content as a percentage of the total phosphorus content.

[0172] Table 1. Analysis results of seven lipid feedstock examples regarding their phosphorus content.

[0173] Feed Total P (wppm) Lipophilic P (wppm) Lipophilic P (% of total P) Animal fat 110 1.6 1 Used cooking oil 15 1.5 10 Brown grease 120 27 23 Industrial corn oil 30 1.6 5 Vegetable acid oil 170 1.7 1 Tall oil pitch 35 2.6 7 Crude tall oil 20 1.5 8

[0174] As can be seen from Table 1, the total phosphorus content varies from 15 to 170 wppm, being highest for vegetable acid oil and lowest for used cooking oil. However, although their total P contents are different, their lipophilic phosphorus contents are close to each other except for brown grease. Also, although the total P contents of animal fat and brown grease seem relatively similar (110 and 120 wppm), their effects are very different from the perspective of catalyst life. It is found that after a common degumming pretreatment, for example, brown grease will have a much greater adverse effect on catalyst life than animal fat. How the ratio of lipophilic phosphorus compounds to the total phosphorus content varies in different samples can be seen from the last column.

[0175] Example 2: Other feedstock samples

[0176] Other samples were analyzed by the same method, which showed greater variability between different samples. They were measured from real feedstock samples. Although they can be classified based on their origin (plant or animal) and refining process, the differences between samples in the same category reveal their true characteristics and unpredictability as waste and residual materials. Table 2 gives the analyzed lipophilic phosphorus compound contents in samples of used cooking oil (UCO), palm oil mill effluent (POME), animal fat (AF), brown grease (BG), their combinations and / or their bleached products (BL). Based on the analysis results (such as those shown in Table 2), it can be found that feedstock such as blends need pretreatment. And, suitable blending partners can be selected based on such analysis results. Knowing the total amount of lipophilic phosphorus compounds in the samples enables the calculations required for pretreatment by blending and / or optionally selecting the conditions for other pretreatments.

[0177] Table 2. Other lipophilic phosphorus content results from different feedstock samples.

[0178]

[0179]

[0180] The above results identified in Table 2 indicate the variability in the content of phosphorus impurities that may be contained in the feedstock. Lipophilic phosphorus, which may be more difficult to remove via pretreatment, may unexpectedly constitute a large portion of the total phosphorus content in the feed, making the feed unsuitable for effective pretreatment for subsequent use in hydroprocessing. Identifying such a situation can allow for more effective feedstock selection and / or pretreatment selection. For example, a pretreatment via blending can be used for feedstocks with a high lipophilic phosphorus content to help reduce the total lipophilic phosphorus content in the feedstock before feeding the feed into the hydroprocessing process. The reduction of lipophilic phosphorus in the total phosphorus content can help bring the feed within a preselected phosphorus content range (e.g., less than 2 wppm lipophilic phosphorus, between less than 2 wppm lipophilic phosphorus and 0.1 wppm lipophilic phosphorus, between 1.5 wppm lipophilic phosphorus and 0.1 wppm lipophilic phosphorus, etc.). And, a suitable pretreatment scheme that can help provide the required phosphorus content in the feed can be selected to provide the required lipophilic phosphorus content within the feed in a more effective manner so that a feed within a preselected lipophilic phosphorus content threshold can be more routinely provided for hydroprocessing. This can help avoid (or at least reduce) catalyst deactivation and extend the life of the hydroprocessing catalyst.

[0181] Example 3: Removal of P model compounds with different degrees of lipophilicity

[0182] Four commercially available P compounds with different lipophilicities were purchased: trioctylphosphine A, trioctyloxide B, 18:0 lysophosphatidylglycerol C, and octadecylphosphonic acid D, to reduce lipophilicity.

[0183]

[0184] Protocol 1. Sample compounds A, B, C, and D.

[0185] Samples were prepared by adding the four (A, B, C, D) model compounds to purified vegetable oil. In the SPE separation, it was found that the first two compounds eluted in the lipophilic fraction, while octadecylphosphonic acid and 18:0 lysophosphatidylglycerol eluted later in the amphiphilic fraction. Figure 1 The separation of the model compounds into a lipophilic P phase (A and B) and an amphiphilic P phase (C and D) in the present SPE method is shown. Thus, the results verified the separation efficiency of the SPE method for lipophilic P.

[0186] This result is related to the purification of lipid oil through pretreatment. Samples containing the corresponding model compounds were prepared to correspond to an elemental phosphorus concentration of ~7 wppm. Then, the samples were bleached (with a 2.5 wt-% dose of acidic mineral adsorbent). For the two lipophilic compounds (phosphine and phosphine oxide), the P concentration in the model solution decreased to 0.8 wppm after bleaching, again corresponding to elemental phosphorus. For the amphiphilic P compounds, the P content in the bleached product was 0.2 wppm, indicating how amphiphilic impurities are more easily removed from the lipid matrix through surface chemical reactions than lipophilic impurities. Figure 2 The bleaching results of lipophilic (A and B) and amphiphilic (C and D) model compounds are also given.

[0187] In this example, the concentration of the P compound was moderate and the adsorbent dose was high, which explains the relatively good purification of lipophilic P. As can be seen in the example, bleaching (including adsorption as a key phenomenon) can remove an appropriate amount of lipophilic P, but the adsorbent cost is too high.

[0188] Example 4: Selecting a suitable pretreatment to minimize lipophilic phosphorus in animal fat samples

[0189] Three filtered animal fat samples were bleached, and the residual P (total phosphorus) in the bleached products was analyzed (the results are in Table 3). Heat treatment of animal fat effectively alleviated the influence of lipophilic phosphorus compounds therein, because the heat-treated animal fat could be bleached to a low residual P concentration, presumably due to the thermal degradation of phospholipids or their lipophilic derivatives. This example demonstrates how tracking the lipophilic phosphorus concentration in the feed sample can be used to select an effective pretreatment method.

[0190] Heat treatment (HT) was carried out by heating 600 g of the feed in a 1 L stirred autoclave reactor from Parr Instruments at 500 rpm. The feed was heated to 280 °C (equilibrium pressure) and held at 280 °C for 30 min, then cooled to approximately 60 °C. In this laboratory experiment, the heating time was 30 min, the cooling time was 20 min, and the reaction time after heating and before cooling was 30 min. The treatment severity was roughly equivalent to treating for 45 min at 280 °C in a tubular reactor setup. The heat-treated product was bleached. Citric acid (2000 mg / kg sample) was added at 85 °C, followed by mixing, 1 wt-% bleaching earth was added, mixed, and the sample was dried using vacuum and filtered at 105 °C. The conditions were the same in all bleaching tests.

[0191] Table 3. Residual P concentration (wppm) in the bleached samples. The samples were bleached using a 1 wt-% dose of acidic mineral adsorbent.

[0192] Sample Filtered and bleached feed Heat-treated and bleached Animal fat 1 8.4 1.7 Animal fat 2 16.8 0.7 Animal fat 3 23.5 1.3

[0193] The results of Example 4 shown in Table 3 indicate that filtration and bleaching cannot remove P(total) to a satisfactory purity, and the residual phosphorus is expected to contain lipophilic phosphorus compounds that are difficult to remove. We believe this to be the case because, as discussed above, lipophilic P cannot be removed well by degumming or bleaching, which depends on the amphiphilic nature of the phosphorus impurities to be removed. Additionally, Example 2 shows that, in general, lipophilic P forms a large portion of the total P in the bleached product (since it has a lower removal rate during bleaching compared to other P impurities), and, in general, lipophilic P is a smaller portion of the total P in the untreated feedstock.

[0194] The results shown in Table 3 above indicate that the combination of heat treatment and bleaching used as a pretreatment for the sampled feedstock can effectively remove lipophilic phosphorus and reduce the total phosphorus to a preferred concentration level. In contrast, filtration and bleaching do not provide such effective phosphorus removal. As discussed above, we believe this is due to the high lipophilic phosphorus content in these samples.

[0195] The combination of heat treatment and bleaching can provide a reduction in phosphorus, which is 78.8% higher in phosphorus removal compared to filtration and bleaching of animal fat 1 sample. For animal fat 2 sample, the combination of heat treatment and bleaching can provide a reduction in phosphorus, which is 95.8% higher in phosphorus removal compared to filtration and bleaching. For animal fat 3 sample, the combination of heat treatment and bleaching can provide a reduction in phosphorus, which is 95.5% higher in phosphorus removal compared to filtration and bleaching.

[0196] The combination of heat treatment and bleaching produced excellent purification results, indicating that the analysis of lipophilic phosphorus provides relevant information for the selection of pretreatment for lipid feedstock.

[0197] Example 5: Solid Phase Extraction (SPE) Details

[0198] A solid phase extraction (SPE) method for the analysis of lipophilic phosphorus was developed. Figure 3 An example chromatogram is given.

[0199] Sample preparation. The sample was melted in an oven at 60 °C for 10 - 15 min. 2.00 ± 0.10 g of the sample was transferred to a 20 mL vial using a glass pipette and mixed with 2 mL of n - heptane to dissolve the sample. The sample vial was placed in a warm water bath at 50 °C for 2 - 3 min and shaken well before injecting into the SPE column.

[0200] Solvents. All analyses were performed using analytical grade n-heptane, isopropanol, and methanol received from VWR. SPE parameters. The instrument used was a CombiFlash NextGen 300+ equipped with a disposable 24 g silica gold column from Teledyne. The method used was set as follows: liquid sample loading type, solvent flow rate 45 mL / min, evaporative light scattering detector, UV detector wavelength 1 - 275 nm, UV detector wavelength 2 - 385 nm. The solvent gradient was indicated in the chromatogram as 0 - 3.5 min (95% n-heptane, 5% isopropanol), 3.5 - 6 min (100% isopropanol), 6 - 9 min (60% methanol, 40% isopropanol), 9 - 10 min (100% n-heptane). The lipophilic fraction (0 - 4.7 min, tubes 1 - 8) and the amphiphilic fraction (4.7 - 12 min, tubes 9+) were collected in pre-weighed 500 mL round-bottom flasks, and the solvent was evaporated using a rotary evaporation system according to the system manual. After removing the solvent, the lipophilic and amphiphilic fractions were weighed, and the total P content in the lipophilic fraction was measured by the ICP-MS / MS method.

[0201] The foregoing description has provided a full and detailed description of the best mode currently contemplated by the inventors for carrying out the invention by way of specific implementations and non-limiting examples of embodiments. However, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing embodiments, but rather can be implemented in other embodiments using equivalent means or in different combinations of multiple embodiments without departing from the characteristics of the invention.

[0202] In addition, some features of the previously disclosed exemplary embodiments can be advantageously used without correspondingly using other features. Accordingly, the foregoing description should be regarded as illustrative only of the principles of the invention and not as a limitation thereof. Thus, the scope of the invention is limited only by the appended patent claims.

Claims

1. A method for producing renewable hydrocarbons suitable for use in fuel applications from a renewable feedstock comprising at least one or more lipophilic phosphorus compounds, the method comprising the following steps: (i) Providing a renewable feedstock, wherein the total amount of lipophilic phosphorus compounds calculated as elemental phosphorus is greater than 2 wppm of the total feedstock weight; (ii) Subjecting the renewable feedstock to at least one pretreatment to obtain a pretreated renewable feedstock, wherein the total amount of lipophilic phosphorus compounds calculated as elemental phosphorus is lower than the total amount of lipophilic phosphorus compounds of the renewable feedstock in step (i), preferably less than 2 wppm of the weight of the pretreated feedstock, preferably less than 1.5 ppm; (iii) Subjecting the pretreated renewable feedstock to at least one catalytic hydrotreating step to obtain renewable hydrocarbons.

2. The method according to claim 1, wherein, Two or more feedstock pretreatments are carried out in sequence in step (ii).

3. The method according to claim 1 or 2, wherein The pretreatment is selected from degumming, heat treatment, heat treatment using an adsorbent, acid treatment, filtration, bleaching, blending or any combination thereof.

4. The method according to claim 2, wherein, The combination of pretreatments consists of a combination of blending and heat treatment in that order.

5. The method according to any one of the preceding claims, wherein, Selecting at least one pretreatment step based on data regarding the ability of the pretreatment to reduce the total amount of lipophilic phosphorus compounds in the feedstock; and subjecting the renewable feedstock to at least one such selected pretreatment.

6. The method according to any one of the preceding claims, wherein, The pretreated renewable feedstock is hydrotreated in the presence of a catalyst selected from Pd, Pt, Ni, Co, Mo, Ru, Rh, W or any combination thereof, such as CoMo, NiMo, NiW, CoNiMo, NiMoW or together with SAPO-11, SAPO-41, ZSM-22, ZSM-23, ZSM-12, ZSM-48, ZSM-5, beta zeolite, ferrierite and mixtures thereof, such as Pt / SAPO-11 / Al2O3, Pt / ZSM-22 / Al2O3, Pt / ZSM-23 / Al2O3, Pt / SAPO-11 / SiO2, optionally on a support, wherein the support is preferably alumina and / or silica, and recovering the obtained liquid product containing renewable hydrocarbons.

7. The method according to any one of the preceding claims, wherein, The catalytic hydrotreating includes one or more of hydrodeoxygenation, hydroisomerization and hydrocracking.

8. The method according to any one of the preceding claims, wherein, The renewable hydrocarbons suitable for use in fuel applications contain components for renewable diesel, sustainable aviation fuel, renewable gasoline or any combination thereof, preferably at least one or more of the following: renewable diesel components meeting the requirements of EN15490-2018, sustainable aviation fuel components meeting the requirements of Annex 2 of ASTM D7566-2020, renewable gasoline components suitable for fuel applications where the fuel meets the requirements of SFS EN 228-2012.

9. The method according to any one of the preceding claims, wherein, The renewable raw materials include at least one of the following: acidulated soapstock (ASK), poultry fat, dry rendered poultry fat (AFP), brown grease (BG), used cooking oil (UCO), tall oil, tall oil fraction, crude tall oil (CTO), tall oil pitch (TOP), palm oil mill effluent (POME), crude palm oil (CPO), palm oil, palm seed oil, palm fatty acid distillate (PFAD), babassu oil, karanja oil, coconut butter, mowrah butter, sesame oil, corn oil, poppy seed oil, cottonseed oil, soybean oil, laurel oil, jatropha oil, palm kernel oil, camelina oil, archaeal oil, bacterial oil, fungal oil, protozoal oil, algal oil, seaweed oil, mustard seed oil, oil from halophiles, soybean oil (SBO), industrial corn oil, rapeseed oil (RSO), canola oil, sunflower oil, hempseed oil, olive oil, linseed oil, mustard oil, peanut oil, castor oil, coconut oil, lard, tallow, whale oil, spent bleaching earth oil (SBEO), lignocellulosic-based feedstock, or any mixture thereof.

10. The method according to any one of the preceding claims, wherein, Determining the total amount of the lipophilic phosphorus compound is carried out by analysis, which includes separating at least one fraction containing the lipophilic phosphorus compound from the raw material or the pretreated raw material, and analyzing the fraction to provide data on at least one lipophilic phosphorus compound.

11. The method according to claim 10, wherein, The separation includes solid phase extraction (SPE) or flash chromatography, preferably SPE.

12. The method according to claim 11, wherein, The SPE includes using a solvent system, preferably a set of solvents with increasing solvent polarity in the solvent system for the extraction. Use of separation and analysis to provide data on at least one lipophilic phosphorus compound in a renewable raw material in the catalytic production of renewable hydrocarbons, the use further including, based on the separation and analysis, selecting a pretreatment capable of reducing the content of the lipophilic phosphorus compound, and subjecting the renewable raw material to the selected pretreatment to provide a pretreated renewable raw material.

14. The use according to claim 13, wherein, The total amount of the lipophilic phosphorus compound calculated as elemental phosphorus in the pretreated renewable raw material is lower than the total amount of the lipophilic phosphorus compound in the renewable raw material, preferably less than 2 wppm of the weight of the pretreated renewable raw material, more preferably less than 1.5 wppm.

15. The use according to claim 13 or 14, wherein, The separation and analysis include the following steps: (a) Collecting at least one sample of the renewable raw material; (b) Separating at least one fraction containing the lipophilic phosphorus compound from the sample; and (c) Analyzing the fraction to provide data on the total amount of the lipophilic phosphorus compound in the renewable raw material.

16. The use according to any one of claims 13-15, wherein, The separation in step (ii) includes solid phase extraction (SPE) or flash chromatography, preferably SPE.

17. The use according to any one of claims 13 - 16, wherein, Two or more pretreatments are carried out in sequence.

18. Use according to any one of claims 13-17, wherein The pretreatment or the multiple pretreatments are selected from degumming, heat treatment, heat treatment with an adsorbent (HTA), acid treatment, filtration, bleaching, blending, or any combination thereof.

19. The use according to any one of claims 13-18 further comprises subjecting the pretreated renewable raw material to at least one catalytic hydrotreating to obtain renewable hydrocarbons.

20. The use according to any one of claims 13-19 for reducing the loss of the activity of the hydrotreating catalyst.

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