Process for producing renewable hydrocarbons

Abstract

The present invention relates to a method for producing renewable hydrocarbons from an oxygen-containing renewable feedstock, the feedstock containing dissolved impurities selected from impurities containing phosphorus and impurities containing at least one metal, the feedstock further containing at least one of triglycerides and free fatty acids, the method comprising the steps of obtaining a net elementary charge based on phosphorus and at least one metal of a first feedstock; mixing the first feedstock with an elementary charge balancing component to obtain a purified feedstock, the purified feedstock having a net elementary charge in the range of -5 to 15 mmol elementary charge / kg of purified feedstock; subjecting the purified feedstock to a heat treatment at a temperature of 180 to 400°C to precipitate compounds comprising the phosphorus and the at least one metal; removing the resulting precipitated compounds comprising the at least one metal and the phosphorus to obtain a purified feedstock; and subjecting the purified feedstock to hydrotreatment using a catalyst sensitive to at least one of the impurities.

Description

[Technical field]

[0001] The present invention relates to a process for producing renewable hydrocarbons from renewable feedstocks. [Background technology]

[0002] Considering climate change and the decline of natural resources, such as fossil oil, there is a need to reuse various feedstocks, for example in the production of plastics or fuels, and in other chemical industries. Sources of feedstocks for such applications are used oils, by-streams and waste from the food industry. However, the quality and content of such feedstocks vary greatly from batch to batch, even from the same source, and the sources are usually such that a particular source is not industrially exploitable by itself. In fact, these types of feedstocks contain various impurities, which cause problems in their processing, especially hydroprocessing. Typically, such feedstocks contain different types of impurities than fossil-derived feedstocks.

[0003] Particularly difficult impurities are phosphorus and metals, especially in feedstocks intended for hydrotreating. These can be partially removed from the feedstock by bleaching or heat treatment or both, but removal of phosphorus in particular is not fully effective. In some feedstocks it is not possible to effectively remove metals, and high metal contents can cause problems in the refining process.

[0004] Therefore, there is a need to provide an effective method for producing renewable hydrocarbons from renewable feedstocks. It is therefore an object to provide a method that involves purifying a renewable feedstock from impurities that cause problems in hydroprocessing. Another object is to provide a method for purifying a renewable feedstock to a purity sufficient for further hydroprocessing of the feed. Summary of the Invention

[0005] The present invention is defined by the features of the independent claims. Some specific embodiments are defined in the dependent claims. In one aspect, a method for producing renewable hydrocarbons from an oxygen-containing renewable feedstock, the feedstock comprising dissolved impurities selected from phosphorus-containing impurities and at least one metal-containing impurity, the feedstock further comprising at least one of triglycerides and free fatty acids, the method comprising: a) obtaining a net elementary charge Q1 based on phosphorus and at least one metal in a first feedstock; b) mixing the first feedstock with a charge balancing component to obtain a feedstock to be purified, the feedstock to be purified having a net charge balance component based on phosphorus and at least one metal, Qt, in the range of -5 to 15 mmol charge balance component / kg of feedstock to be purified; c) subjecting the purified feedstock to a heat treatment at a temperature of 180-400° C. to precipitate compounds containing the phosphorus and the at least one metal; d) removing the resulting precipitated compounds comprising said at least one metal and said phosphorus to obtain a purified feedstock; and e) subjecting said purified feedstock to hydrotreating using a catalyst sensitive to at least one of said impurities. A method is provided that includes: [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 illustrates the efficiency of conversion of dissolved phosphorus to solid phosphorus compounds as a function of temperature and time, according to one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] In this specification, weight percent (wt-%) is calculated based on the total weight of the material in question (typically a blend or mixture). Volume percent (vol-%) is also calculated based on the total volume of the material in question (typically a blend or mixture). All amounts defined as ppm (parts per million) are based on weight.

[0008] The term "renewable" in the context of a renewable fuel component refers to one or more organic compounds derived from any renewable source (i.e., not derived from any fossil-based source). Thus, a renewable fuel component is based on a renewable source and, as a result, does not derive from or originate from any fossil-based material. The term fuel refers to both fuels that can be used as is and fuel components that meet the specification requirements for their respective uses. For example, within the EU, the specification for gasoline is EN 228 (2017), the specification for regular diesel is EN 590 (2017), the specification for paraffinic diesel is EN 15940 (2019), the specification for regular aviation fuel is D1655 (2020), and the specification for aviation turbine fuel containing synthetic hydrocarbons is D7566 (2020).

[0009] 14 The C-isotope content can be used as evidence of the renewable or biological origin of a feedstock or product. Carbon atoms in renewable materials contain less stable radioactive carbon ( 14 C) There are more atoms. Therefore, 12 C and 14By analyzing the isotope ratio of C, it is possible to distinguish carbon compounds from biological sources from fossil sources. Thus, the specific ratio of the isotopes can be used to identify and quantify renewable carbon compounds and to distinguish them from non-renewable, i.e., fossil-derived carbon compounds. The isotope ratio does not change during the course of a chemical reaction. An example of a suitable method for analyzing carbon content from biological sources is ASTM D6866-20 (2020). An example of how to apply ASTM D6866-20 to measure the renewable content in fuels is described in Dijs et al., Radiocarbon, 48(3), 2006, pp315-323. For the purposes of the present invention, a carbon-containing material, such as a feedstock or product, is considered to be of renewable origin if it contains 90% or more modern carbon (pMC), e.g., about 100% modern carbon, as measured using ASTM D6866-20.

[0010] In this specification, when "feedstock" is discussed, both the first and optionally the second feedstock (and possible further feedstocks) are meant unless otherwise specified. The terms "net elementary charge" and "elementary charge" can be used interchangeably, as can the terms "elementary charge balancing component" and "balancing component". Furthermore, when "net elementary charge Q" or "net elementary charge" is mentioned and a formula for its calculation is given, the same formula is used for all net elementary charges and the units are mmol elementary charge / kg of feedstock. Elementary charge, also written as e, is the charge carried by one proton, or equivalently, the magnitude of the negative charge carried by one electron. The term "net elementary charge of a feedstock" means the net elementary charge of phosphorus and at least one metal contained in the feedstock, and the term "net elementary charge of a feedstock" is used for simplicity. The unit of the net elementary charge of a feedstock when expressed numerically is mmol elementary charge / kg of the feedstock, but for simplicity, mmol elementary charge / kg may be used. "Dissolved impurities" in this specification means impurities remaining in the liquid phase after filtration, for example, using a 2 μm filter, and solid impurities removed by such filtration are not considered dissolved impurities in this specification. Furthermore, in this specification, "at least one" means that there are one or more of the listed items. When "heat treatment" is mentioned, it means a heat treatment of purification, i.e., a purification heat treatment, and does not mean a hydrotreatment using heat. "Purification" means that the amount of dissolved impurities is reduced.Whenever reference is made to the purification or removal of impurities or the reduction in the amount of impurities, dissolved impurities are meant, even if not specifically mentioned.

[0011] In one aspect of the invention, there is provided a method for producing renewable hydrocarbons from an oxygen-containing renewable feedstock, the feedstock comprising dissolved impurities selected from phosphorus-containing impurities and at least one metal-containing impurity, the feedstock further comprising at least one of triglycerides and free fatty acids, the method comprising: a) obtaining a net elementary charge Q1 based on phosphorus and at least one metal in a first feedstock; b) mixing the first feedstock with a charge balancing component to obtain a feedstock to be purified, the feedstock to be purified having a net charge balance component based on phosphorus and at least one metal, Qt, in the range of -5 to 15 mmol charge balance component / kg of feedstock to be purified; c) subjecting the purified feedstock to a heat treatment at a temperature of 180-400° C. to precipitate compounds containing the phosphorus and the at least one metal; d) removing the resulting precipitated compounds comprising said at least one metal and said phosphorus to obtain a purified feedstock; and e) subjecting said purified feedstock to hydrotreating using a catalyst sensitive to at least one of said impurities. A method is provided that includes:

[0012] Thus, the method provides an effective way to purify various renewable feedstocks containing phosphorus and / or metals so that these feedstocks can be used in hydroprocessing to produce renewable hydrocarbons. Phosphorus is typically in the form of phospholipids in the feedstock being treated, and metals can be present as salts of fatty acids or in phospholipids. Metals typically include alkali or alkaline earth metals and some other metals, such as Fe, Al, Cr, Pb, Mn, Zn, W, Ni, and Cu. Metals can be selected from the group consisting of Na, K, Mg, Ca, Fe, Al, Cr, Pb, Mn, Zn, W, Ni, and Cu, or combinations thereof. The term "net elementary charge based on phosphorus and a least one metal in a feedstock" means that all metals and phosphorus in the feedstock are taken into account. Although there may be only one metal in the feedstock, typically there are several metals, all of which need to be taken into account. If the amount of metal is near or above the detection limit (i.e., too small to be detected), such as less than 1 ppm or less than 0.1 ppm, it does not essentially affect the process.

[0013] After heat treatment, the refined feedstock contains dissolved phosphorus in an amount of up to 10 mg / kg of feedstock and dissolved metals in an amount of up to 40 mg / kg of feedstock. After further bleaching, the refined feedstock contains dissolved phosphorus in an amount of up to 5 mg / kg of feedstock and dissolved metals in an amount of up to 10 mg / kg of feedstock.

[0014] The heat treatment reduces the amount of dissolved phosphorus by at least 60% compared to the feedstock being refined and reduces the amount of dissolved metals by at least 60% compared to the feedstock being refined. If the heat treatment is followed by a further bleaching treatment, the amount of dissolved phosphorus is reduced by at least 80% compared to the feedstock being refined and the amount of dissolved metals is reduced by at least 80% compared to the feedstock being refined.

[0015] Feedstocks that can be treated using the method of the present invention contain triglycerides and / or free fatty acids. Phosphorus and metals are catalyst poisons, especially in hydroprocessing. High metal contents can be largely removed by the addition of an appropriate acid, but phosphorus removal is more difficult.

[0016] Thus, the impurities in dissolved form in the treated feedstock include impurities containing phosphorus and impurities containing one or more metals. Although phosphorus and one or more metals may be present in the same impurity, they are most typically present in different impurities, i.e., as separate compounds within the feedstock. As used herein, treated feedstock refers to a feedstock that contains less soluble phosphorus and / or metals compared to the original feedstock.

[0017] For example, feedstocks such as acidified soapstock (ASK), dry rendered chicken fat (AFP) and brown grease (BG) cannot be refined by themselves using bleaching alone to a degree that would then be suitable for hydrodeoxygenation (HDO). Typically, in feedstocks consisting of acid soapstock or chicken fat, a large amount of residual phosphorus remains after conventional refining methods. In the case of brown grease, the main problem is the high metal content. Due to the very high metal content, in the bleaching of brown grease, the product exhibits very high filtration resistance or even clogging.

[0018] However, it is possible to blend, for example, acidified soapstock and brown grease, or chicken fat and brown grease, and if the blend is optimal, both phosphorus and metals can be removed from the feedstock blend using the method of the present invention, and the resulting refined feedstock can be used for hydroprocessing. Typically, the amount of dissolved impurities in the feedstocks of various processes that use catalysts affects the catalyst life, and the higher the amount of a particular dissolved impurity, the shorter the catalyst life. In one example, the amount of dissolved phosphorus in the feedstock for HDO is preferably less than 2 ppm, while the amount of dissolved metals is as low as possible, for example, at most 5 ppm.

[0019] The various renewable feedstocks envisaged include materials with high to very high amounts of phosphorus and / or metals. For example, acidified soapstock and chicken fat may contain 100-400 ppm phosphorus, while oils or fats of algal origin may contain several thousand ppm phosphorus. Brown grease typically has a phosphorus content that is less than 100 ppm, while the amount of metals may be several hundred or several thousand ppm. Thus, the method of the present invention is particularly suitable for feedstocks with high phosphorus and / or metal contents, but of course may also be used for materials with lower impurity contents.

[0020] In one embodiment, the renewable feedstocks treated, i.e., purified, using the method of the present invention contain dissolved impurities comprising phosphorus in an amount of at least 50 ppm, or at least 100 ppm, or at least 200 ppm, or at least 300 ppm, or at least 400 ppm, or at least 500 ppm. Such feedstocks may also contain dissolved impurities comprising at least one metal in an amount of at least 200 ppm, or at least 500 ppm, or at least 1000 ppm.

[0021] Without wishing to be bound by theory, it is believed that during the refinery heat treatment of the feedstock, metal phosphates are likely formed from phospholipids and metals present in the feedstock (e.g., in phospholipids or fatty acids), and the formed metal phosphates can then be removed from the feedstock. The metal phosphates can be removed, for example, as a precipitate, which can be easily filtered. Thus, less dissolved metals and phosphorus can be present in the subsequent process, and catalyst deactivation and clogging can be reduced, for example, in the hydroprocessing of the refined feedstock to fuels.

[0022] That is, the objective is to balance the metals and phosphorus in the feedstock to a sufficient degree to optimize the formation of metal phosphates during heat treatment, i.e., to ensure sufficient metal cations to balance the phosphate (anions) released from the phospholipids.

[0023] In other words, the feedstock after heat treatment and optional precipitate removal is preferably suitable for hydrodeoxygenation. Typically, the feedstock entering the hydrodeoxygenation reactor or its catalyst bed should not contain more than 10 ppm, preferably more than 5 ppm, more preferably more than 1 ppm of alkali metal and alkaline earth metal impurities, calculated as elemental alkali metal and alkaline earth metal; more than 10 ppm, preferably more than 5 ppm, more preferably more than 1 ppm of other metals, calculated as elemental metals; more than 30 ppm, preferably more than 15 ppm, more preferably more than 5 ppm of phosphorus-containing impurities, calculated as elemental phosphorus. As for impurities other than phosphorus, and metals such as sodium, potassium, magnesium, calcium and iron, the excess is typically removed by other methods known per se.

[0024] Metal phosphates can be removed as precipitates that can be easily filtered. The precipitates can be, for example, iron, sodium, potassium, magnesium and / or calcium phosphates. By heat treatment, the amount of dissolved metals and phosphorus is low enough for subsequent processing and catalyst deactivation and clogging can be avoided, for example, in hydroprocessing of the treated feedstock to fuel. Thus, the treated or purified feedstock is a feedstock that contains less phosphorus and / or metals compared to the original feedstock. If filtration is used to remove precipitate compounds, the filtration preferably removes at least 90 wt-% of the precipitate, for example at least 95 or 99 wt-% of the precipitate. If another method for removing precipitates from the heat-treated feedstock is used, the efficiency of removal is preferably within the same range as for filtration.

[0025] As used herein, less dissolved impurities or reduced amounts of dissolved impurities means that the amount of dissolved phosphorus and / or metals is, for example, up to 20 wt-% of the original amount of these dissolved impurities, which amounts may be selected, for example, independently, up to 20, 15, 10, 5, 3 or 1 wt-% of the original amount of each dissolved impurity.

[0026] The term "hydrotreating" or "hydrotreatment" refers to a chemical unit operation in which the reaction of hydrogen is used to remove impurities such as oxygen, sulfur, nitrogen, phosphorus, silicon and metals, especially as part of petroleum refining. Hydrotreating also includes hydroisomerization. Hydrotreating can be carried out in one or several steps in one or more reactor units or catalyst beds. Preferably, hydrotreating is carried out in two steps. For example, one-step hydrotreating can consist of hydrodeoxygenation and hydroisomerization in a single step, and two-step hydrotreating can consist first of a hydrodeoxygenation step and then a hydroisomerization step.

[0027] Hydrotreating therefore means hydrodeoxygenation (HDO), i.e. essentially removing oxygen as water in the presence of molecular hydrogen under the influence of a (HDO) catalyst; hydroisomerization (HI), i.e. branching of n-paraffins to form i-paraffins in the presence of molecular hydrogen under the influence of a (HI) catalyst; hydrodesulfurization (HDS), i.e. removing sulfur as hydrogen sulfide with molecular hydrogen under the influence of a (HDS) catalyst; hydrodemetallization (HDM), i.e. removing metals by trapping them with a (HDM) catalyst; hydrodenitrogenation (HDN), i.e. removing nitrogen with molecular hydrogen under the influence of a (HDN) catalyst; hydrodearomatization (HDA), saturating or ring-opening aromatics with molecular hydrogen under the influence of a (HDA) catalyst. Typically hydrotreating means hydrodeoxygenation by hydrodeoxygenation (HDO) and hydrogenation of double bonds. Additionally, hydroisomerization may be carried out simultaneously or successively with HDO.

[0028] To obtain an optimal result of the heat treatment, i.e. to sufficiently reduce the level of dissolved impurities in the feedstock, the net elementary charge Q1 of the first feedstock is balanced with an elementary charge balancing component. The elementary charge balancing component is selected so that after mixing the first feedstock with the elementary charge balancing component to obtain the feedstock to be purified, the feedstock to be purified has a net elementary charge Qt in the range of -5 to +15 mmol elementary charge / kg of the feedstock to be purified. Thus, the net elementary charge Qt of the feedstock to be purified is -5 to +15 mmol elementary charge / kg of the feedstock to be purified. The net elementary charge Qt can be, for example, -5, -4.5, -4, -3.5, -3, -2.5, -2, -1.5, -1, -0.5, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, or 14 mmol elementary charge per kg of feedstock to be purified to -4, -3.5, -3, -2.5, -2, -1.5, -1, -0.5, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 mmol elementary charge per kg of feedstock to be purified.

[0029] The net elementary charge of the treated feedstock is typically selected with a view to further processing of the feedstock. Indeed, different further processes require different levels of purity with respect to phosphorus and metals. For example, the further process may use a catalyst that is sensitive to one of the impurities of interest, and different catalysts have different tolerances to the impurity. The following example shows that the closer the net elementary charge of the treated feedstock is to 0, the better the refining result will be, i.e., the more the amount of the dissolved impurity of interest in the feedstock can be reduced. The net elementary charge of the treated feedstock may also depend on the net elementary charge of the components of the treated feedstock. For example, some algal oils may have a net elementary charge of up to -70 mmol / kg, while some brown greases may have a net elementary charge of up to +200 mmol / kg. For such feedstocks, balancing their charges to a range of -5 to +15 mmol / kg of feedstock means that the treated feedstock can be used for hydroprocessing. This charge balancing therefore provides a means to utilize feedstocks of various qualities and makes further processing cheaper and easier, i.e. less costly to remove certain impurities. For example, the net elementary charge of the treated feedstock may be -1 to +5 or -0.5 to +3 mmol elementary charge / kg if the treated feedstock is used for hydroprocessing with phosphorus and / or metal sensitive catalysts. In one embodiment, particularly where sodium and iron are problematic and therefore the feedstock contains significant amounts of either or both of these metals and subsequent use uses sensitive catalysts, the net elementary charge of the treated feedstock should be as close to 0 as possible, typically within the range of -0.5 to +1 mmol elementary charge / kg of treated feedstock.

[0030] In a preferred embodiment, the net elementary charge before heat treatment is greater than 0 mmol elementary charge / kg, so that there is an excess of metal rather than phosphorus in the feedstock being treated. The optimal net elementary charge also depends on the feedstock. For example, if the feedstock has a significant phosphorus content, the net elementary charge will preferably be greater than 0 mmol elementary charge / kg to ensure effective reduction of dissolved phosphorus. In practice, the total net elementary charge of the feedstock being treated is preferably slightly positive (meaning a surplus of metal) to ensure that the dissolved phosphorus is converted as well as possible to insoluble phosphorus compounds. Having a slight surplus of dissolved metal in the feed after this heat treatment can be addressed by removal of the metal using a sufficient acid dosage in a subsequent refining step, if necessary. In the above example of acidified soapstock and brown grease, the conversion of dissolved metal to metal phosphates leads to, for example, good filtration capacity in subsequent bleaching, and filtration problems that are typical especially for brown grease blends do not occur when using the treatment method of the present invention.

[0031] There are various ways to balance the net elementary charge of the feedstock. According to a method that has proven effective, this is done via the net elementary charge based on phosphorus and metals. In one embodiment, the net elementary charge Q based on phosphorus and at least one metal is given by the following formula (I):

number

[0032] In this formula, i is 1-n, i.e., i is the number of dissolved metals, and i goes from 1 to the number n, where n is the maximum number of the various dissolved metals. For example, i is 1, 2, 3, 4, 5, 6, 7, or 8.

[0033] The total net elementary charge Qt is now the sum of the net elementary charges of each feedstock and, optionally, any charge-balancing components different from the feedstocks, i.e. Qt = Q1 + Q2 + Q3 + ... + Q C where Q1 is the net elementary charge of the first feedstock, Q2 is the net elementary charge of the optional second feedstock, Q3 is the net elementary charge of the optional third feedstock, etc. Q C is the elementary charge of an optional charge-balancing component different from the feedstock.

[0034] The net elementary charge is therefore the sum of the net elementary charges of all metals and phosphorus present.

[0035] In this formula, the feedstock may be the first feedstock or the second feedstock, if used, or any other feedstock if several feedstocks are used. In this application, metal i is typically sodium, potassium, magnesium, calcium and / or iron. The elementary charge of phosphorus, assumed herein to be in the form of phosphate, is -3e in this formula. Depending on the compounds present, the elementary charge of sodium is +1e, the elementary charge of potassium is +1e, the elementary charge of magnesium is +2e, the elementary charge of calcium is +2e, and the elementary charge of iron is +3e. If other dissolved metals are present in the feed in significant amounts, e.g., higher than 1 ppm, they are also taken into account in the calculation of the net elementary charge along with their elementary charge. The same limits may be used for sodium, potassium, magnesium, calcium and iron, again depending on the further use of the feedstock, being significant amounts (e.g., 1 ppm). The feed may also contain certain metals in amounts that cannot be easily detected, and such metals and their elementary charge may not be taken into account. However, the amount is so small that it does not affect the results essentially. Thus, the limit may be 1 ppm, or 0.5 ppm, or 0.1 ppm. The elementary charge of a metal is the valence that the metal typically has when it forms a metal salt, such as a metal phosphate. Those skilled in the art may use other methods to make this determination.

[0036] In fact, in the method of the present invention, the net elementary charge Q1 of the first feedstock is first obtained. The net elementary charge can be obtained as described above. Typically, for the measurement of various concentrations, a sample of the feedstock is filtered to remove any solid particles, and the amount of various metals and phosphorus is measured. Then, formula (I) is used to obtain the net elementary charge. It is observed that it is the dissolved phosphorus and metals that are converted into metal phosphate precipitates, and therefore, for best results, these dissolved impurities need to be balanced (adjust the net elementary charge to close to zero). Therefore, only the concentrations of dissolved phosphorus and metals (not solid impurities) are used to calculate the net elementary charge. Feedstocks treated by heat treatment may contain solid precipitates, but these are not affected by the treatment, and therefore the treated feedstock does not need to be balanced or filtered before being treated.

[0037] The first feedstock is then mixed with an elementary charge balance component to obtain the feedstock to be purified. The elementary charge balance component is selected so that the resulting purified feedstock has a net elementary charge Qt in the range of -1 to 15 mmol elementary charge / kg of feedstock to be purified. This step therefore requires also knowing the net elementary charge of the elementary charge balance component and then calculating the appropriate amount of the elementary charge balance component to reach a net elementary charge Qt within the desired range. This range is selected so that the required degree of purification is achieved, i.e. at least the amount of phosphorus is sufficiently reduced. Advantageously, the amount of metals is also reduced to such an extent that no further metal removal is required.

[0038] It is also possible to mix two feedstocks with a charge balancing component that is different from the feedstocks, i.e., not the feedstocks themselves. Similarly, more than two feedstocks can be mixed, and the net charge of the remainder of the feedstock mixture can be balanced with the charge balancing component. When several feedstocks are mixed, the net charge of each feedstock can be determined first, and then the appropriate amount of the feedstocks can be mixed, and then the net charge of the resulting mixture can be determined before further mixing with the charge balancing component.

[0039] Therefore, the concentrations of metals and phosphorus are calculated on a molar basis and further multiplied by their assumed elementary charge to obtain the trivalent PO4 3- The charge equilibrium point is found as the blend ratio where the negative charge of phosphorus, assumed as (phosphate), is balanced by the sum of the metal charge elementary charges. At the charge equilibrium point, or at a point sufficiently close to the charge equilibrium point for further processing of the feedstock by the method of the invention, phosphorus that is difficult to remove, such as from acidified soapstock or dried rendered chicken fat, may pair with metals, such as from brown grease, and form metal precipitates in the heat treatment.

[0040] Preferably, the net elementary charge is as close to zero as possible, which allows for simultaneous removal of both phosphorus and metals.

[0041] After mixing, the feedstock to be purified is heat treated and precipitated metal and phosphorus-containing compounds are removed, thereby obtaining a purified feedstock, which can be subjected to further processing either directly or after further purification or pretreatment steps or after storage and / or transportation. In fact, after the purification step of the present invention, the feedstock may still need to be further purified to remove some other impurity or impurities. Therefore, the method of the present invention may include other purification steps between the purification heat treatment and the hydrotreatment.

[0042] The purification heat treatment is carried out at an elevated temperature and typically under a pressure. The purification heat treatment may include mixing of the feedstock, but this is not required. Typically, the purification heat treatment is carried out in the absence of added hydrogen and in the absence of a catalyst. The heat treatment may also be carried out in the absence of added acid. Although it is possible to add acid prior to the purification heat treatment, it is usually not carried out during such purification heat treatment. Additionally, the heat treatment may be carried out in the presence of an added adsorbent, for example using a silica-based adsorbent, where the adsorbent is in effective contact with the feedstock to be purified. Steam (water vapor) may be used during the heat treatment. If water is used, it is typically used in an amount of up to 1 wt-%.

[0043] It should be noted that typically various feedstocks, especially those with very mixed origins, are also stored at elevated temperatures, typically above 50° C., to keep the feedstock liquid and to avoid segregation within the feedstock.

[0044] The purification heat treatment is carried out at a temperature of 180-400°C. In one embodiment, it is carried out at a temperature of 180-310°C. In another embodiment, it is carried out at a temperature of 220-300°C. In yet another embodiment, the heat treatment is carried out at a temperature of 200-280°C. Such a temperature range typically allows both to avoid undesired side reactions as much as possible and to optimize the size of the reactor. Thus, the temperature of the heat treatment can be, for example, 180, 185, 190, 195, 200, 205, 210, 215, 220, 225, 230, 235, 240, 245, 250, 255, 260, 265, 270, 280, 285, 290, 300, 310, 320, 330, 340, 350, 360, 370, or 380°C. The temperature may be from 190, 195, 200, 205, 210, 215, 220, 225, 230, 235, 240, 245, 250, 255, 260, 265, 270, 280, 285, 290, 295, 300, 305, 310, 320, 330, 340, 350, 360, 370, 380, 390, or 400°C. The temperature is selected to obtain optimal results for the removal of a given dissolved impurity. Typically, the lower the temperature, the longer the reaction time required. Thus, the temperature may be selected based on other steps in the process, such as the heat treatment time being optimal for feeding the heat-treated feedstock to further steps. The temperature also depends on the dissolved impurities to be removed, as they react differently. The size of the reactor for the heat treatment may also play a role in the selection of the optimal temperature. Side reactions may also be involved, as some feedstocks may contain components that begin to oligomerize or crack at certain temperatures.

[0045] Phospholipids typically begin to decompose at temperatures between 160 and 180°C, but it is often more practical to use longer holding times and higher treatment temperatures for complete decomposition. Treatment conditions can be, for example, 200°C / 210 min, 220°C / 65 min, 250°C / 20 min, 280°C / 10 min to achieve similar treatment effects.

[0046] In one embodiment, the heat treatment is carried out for 1 minute to 3 hours, preferably 15 minutes to 3 hours. The required time typically depends on the temperature, and the higher the temperature, the shorter the required treatment time. Also, some feedstocks may be more sensitive to heat than others. The heat treatment time may thus be, for example, from 1 minute, 5 minutes, 10 minutes, 15 minutes, 30 minutes, 45 minutes, 1 hour, 1 hour 15 minutes, or 1 hour 30 minutes, to 15 minutes, 30 minutes, 45 minutes, 1 hour, 1 hour 15 minutes, 1 hour 30 minutes, 1 hour 45 minutes, 2 hours, 2 hours 15 minutes, 2 hours 30 minutes, 2 hours 45 minutes, 3 hours, etc. It is also possible to use times longer than 3 hours, for example, up to 4 hours or 5 hours. By heat treatment time, we mean herein the effective time, which can be easily calculated by one skilled in the art based on the type of reactor, whether the process is a continuous or batch process, and the heating and cooling times.

[0047] Typically, the heat treatment is carried out in a pressurized reactor, and the pressure during the heat treatment is 2 to 20 MPa. The heat treatment can be carried out at equilibrium pressure, elevated pressure, or pressure lower than the equilibrium pressure.

[0048] There are at least two options for the type of charge balance component. In fact, it can be a second feedstock with a net charge Q2 (positive or negative net charge) based on phosphorus and at least one metal, or it can be selected from metal-containing compounds that can provide metal cations (positive charge) and phosphorus-containing compounds that can provide phosphorus-containing anions (negative charge). Depending on the available feedstocks, it is also possible to use both options. When the charge balance component is a second feedstock, the second feedstock has a net charge Q2 (e.g. positive) based on phosphorus and at least one metal that is electrically opposite to the net charge Q1 (e.g. negative) based on phosphorus and at least one metal in the first feedstock. Electrically opposite in this specification means polarity, not necessarily the magnitude of the net charge. That is, if the first feedstock has a negative net elementary charge (i.e., an excess of phosphorus relative to the metal), the second feedstock and / or the metal-containing compound capable of providing the metal cation should have a positive net elementary charge (i.e., an excess of metal relative to phosphorus), and if the first feedstock has a positive net elementary charge, the second feedstock and / or the phosphorus-containing compound capable of providing the phosphorus-containing anion should have a negative net elementary charge.

[0049] In fact, when current types of feedstocks arrive at the processing station, they are usually accompanied by a certificate of analysis showing the amounts of various components in the feedstock, based on which the charge balance component is selected to be either another feedstock containing the appropriate amount of phosphorus and / or metals, or the appropriate type and amount of a positive charge metal-containing compound or a negative charge phosphorus-containing compound.

[0050] Examples of such metal-containing compounds capable of providing the metal cation are, for example, sodium hydroxide, sodium soap, potassium hydroxide, potassium soap, calcium hydroxide, calcium soap, magnesium hydroxide, magnesium soap, iron hydroxide, iron soap, and mixtures thereof. In this context, soap is a salt of a fatty acid, i.e., for example, sodium soap is a sodium salt of a fatty acid, such as, for example, sodium stearate.

[0051] Examples of such phosphorus-containing compounds capable of providing phosphorus-containing anions are, for example, phosphoric acid, phospholipids, and mixtures thereof.

[0052] The removal of the precipitated compounds formed in step d) may be carried out by at least one method selected from filtration, sedimentation, centrifugation, water washing, degumming and bleaching. In one embodiment, said removal is carried out by degumming with acid and / or water followed by centrifugation. In another embodiment, said removal is carried out by bleaching in the presence of an acid and an adsorbent.

[0053] In one embodiment, the method further comprises at least one of degumming and bleaching after heat treatment. The method may also comprise both degumming and bleaching, and these may be performed in either order, although it is more typical to perform degumming first and then bleaching.

[0054] In embodiments where the further processing is degumming, this may be done by mixing the treated feedstock with an acid, such as phosphoric acid and / or citric acid, and water, and separating the impurities which are removed by centrifugation. The amount of acid is typically in stoichiometric excess, and it hydrates the remaining metals, making them easier to remove.

[0055] In embodiments where the further treatment is bleaching, it may be carried out in the presence of an acid, such as, for example, citric acid and / or phosphoric acid. Bleaching is typically carried out in the presence of a small amount of water. Bleaching may be carried out after filtration of the precipitate formed in the heat treatment.

[0056] Bleaching earth or other adsorbents, such as silica, may be added to the treated feedstock to adsorb impurities. The temperature for bleaching is, for example, 80-90° C. After this, the bleached product is typically dried and filtered to remove solids along with impurities.

[0057] The feedstock can be any type of animal and / or plant-based material that contains oxygen. Typically, the feedstock contains, for example, triglycerides and / or free fatty acids. In one embodiment, the feedstock is selected from the group consisting of: Vegetable fats, vegetable oils, vegetable waxes; animal fats, animal oils, animal waxes; fish fats, fish oils, fish waxes; Fatty acids or free fatty acids obtained from vegetable fats, vegetable oils, vegetable waxes; animal fats, animal oils, animal waxes; fish fats, fish oils, fish waxes and mixtures thereof by hydrolysis, transesterification or pyrolysis; esters obtained by transesterification from vegetable fats, vegetable oils, vegetable waxes; animal fats, animal oils, animal waxes; fish fats, fish oils, fish waxes and mixtures thereof; Metal salts of fatty acids obtained by saponification from vegetable fats, vegetable oils, vegetable waxes; animal fats, animal oils, animal waxes; fish fats, fish oils, fish waxes, and mixtures thereof; Esters obtained by esterification of free fatty acids of vegetable, animal and fish origin with alcohols; Fatty alcohols or aldehydes obtained as reduction products of fatty acids from vegetable fats, vegetable oils, vegetable waxes; animal fats, animal oils, animal waxes; fish fats, fish oils, fish waxes and mixtures thereof; recycled food-grade fats and oils, as well as fats, oils and waxes obtained through genetic engineering; dicarboxylic acids or polyols, including diols, hydroxyketones, hydroxyaldehydes, hydroxycarboxylic acids, and the corresponding di- or polyfunctional sulfur compounds, the corresponding di- or polyfunctional nitrogen compounds; Algae-derived compounds, as well as A mixture of any of these substances.

[0058] In one embodiment of the invention, the feedstock is based on non-edible oils / fats. In another embodiment, the feedstock comprises vegetable oil. In a further embodiment, the vegetable oil is obtained as a by-product from forestry. In a particular embodiment, the feedstock is selected from waste and residues from animal fats or oils, vegetable fats or oils, and fish fats or oils, and mixtures thereof.

[0059] Exemplary feedstocks include at least triglycerides. The most typical exemplary feedstocks are animal fats and palm oil fatty acids, especially those derived from waste and residual materials.

[0060] Further exemplary feedstocks include at least fatty acids. The most typical feedstocks are various vegetable oils and tall oil materials, such as crude tall oil.

[0061] The natural fats or derivatives thereof may be provided in pure form or as part of a feedstock containing other ingredients. Preferably, the feedstock contains at least 20 wt-%, more preferably at least 30 wt-%, and most preferably at least 40 wt-% pure natural fats or oils or derivatives thereof.

[0062] Feedstock is C8~C 24The fatty acids may include fatty acids, derivatives thereof, such as esters of the fatty acids and triglycerides of the fatty acids, metal salts of the fatty acids, or combinations thereof. The fatty acids or fatty acid derivatives, such as esters, may be produced via hydrolysis of bio-oils, by fractionation thereof, or by esterification reactions of triglycerides.

[0063] The feedstock is also C 10 ~C 28 Mono- or diglycerides of fatty acids, C 10 ~C 28 Fatty Acids, Nonglyceride C 10 ~C 28 Fatty acid ester, C 10 ~C 28 Fatty alcohol, C 10 ~C 28 Fatty aldehydes, and C 10 ~C 28 Derivatives of natural fats, including fatty ketones, may also be included. 10 ~C 28 Fatty acids, their mono- and diglycerides are typically prepared by hydrolysis of the corresponding triglycerides. 10 ~C 28 Fatty acid esters are primarily prepared from triglycerides by transesterification. 10 ~C 28 Fatty alcohols, aldehydes and ketones are prepared by reduction of the corresponding fatty acids, typically by hydrogenation. Advantageously, the feedstock hydrocarbon is C 10 ~C 24 It could be.

[0064] The feedstock also contains milk fat containing lauric-myristic acid groups (C 12 ~C 14 ), palmitic acid group (C 16 ), stearic acid group (C 18 ), linoleic acid group (unsaturated C 18 ), the erucic acid group (unsaturated C 22), whale oil and fish oil containing oleostearic acid group (conjugated unsaturated C 18 ), substituted fatty acids such as castor oil (lysine oleate, C 18 ), oils obtained from plants by genetic engineering, and mixtures of two or more of these.

[0065] Derivatives of natural fats also include any of the aforementioned natural fats and derivatives, including those in which the hydrocarbon chains have been modified, for example by substitution, branching or saturation.

[0066] Feedstock oils may be classified as crude, degummed, cooked, and RBD (refined, bleached, deodorized) grades depending on the level of pretreatment and residual phosphorus and metal content. Animal fats and / or oils include non-edible tallow, edible tallow, technical tallow, floating tallow, lard, chicken fat, chicken oil, fish fat, fish oil, and mixtures of any two or more thereof. Grease may include yellow grease, brown grease, waste vegetable oil, restaurant grease, trap grease from municipalities such as water treatment plants, and used oil from industrial packaged food operations, and mixtures of any two or more thereof.

[0067] In one embodiment, the first feedstock and optional second feedstock comprise at least one of animal fat, animal oil, vegetable fat, vegetable oil, fish fat, fish oil, microbial oil, algal oil, waste fat, waste oil, residual fat, residual oil, sludge from vegetable oil production. When more than one or two feedstocks are used, the above may apply to all feedstocks.

[0068] In another embodiment, the first feedstock and the optional second feedstock are selected from the group consisting of acidified soap stock (ASK), chicken fat, dry rendered chicken fat (AFP), brown grease (BG), used cooking oil (UCO), tall oil, tall 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, carinata oil, coconut butter, muscat butter oil, sesame oil, corn oil, poppy seed oil, oil, cottonseed oil, soybean oil, bay seed oil, jatropha oil, palm kernel oil, camelina oil, archaeal oil, bacterial oil, fungal oil, protozoan oil, algae oil, seaweed oil, mustard seed oil, halophilic oil, soybean oil (SBO), technical corn oil, rapeseed oil (RSO), colza oil, canola oil, sunflower oil, hemp seed oil, olive oil, linseed oil, mustard oil, peanut oil, castor oil, coconut oil, lard, tallow, marine animal oil, spent bleaching earth oil (SBEO), lignocellulosic based feed, or mixtures thereof.

[0069] In one embodiment, the hydrotreating comprises hydrodeoxygenation and isomerization, using a temperature in the range of 250-400° C., a pressure in the range of 1-2 MPa, and a hydrogen flow rate in the range of 350-1500 Nl H2 / l feed, where Nl H2 / l means normal liters of hydrogen per liter of feed to the HDO reactor.

[0070] In another particular embodiment, the hydrodeoxygenation reaction conditions are a temperature in the range of 250 to 400° C., a pressure in the range of 2 to 8 MPa, and a reaction time of 0.5 to 3 h. -1 and a hydrogen flow rate of 350-900Nl H2 / l feed, and a hydrodeoxygenation catalyst.

[0071] The hydrotreatment may be carried out at a temperature of 270 to 380°C, for example, 275 to 360°C, or 300 to 350°C. The temperature may be, for example, from 250, 255, 260, 265, 270, 275, 280, 285, 290, 295, 300, 305, 310, 315, 320, 325, 330, 335, 340, 345, 350, 355, 360, 365, 370, 375, 380 or 385°C to 265, 270, 275, 280, 285, 290, 295, 300, 305, 310, 315, 320, 325, 330, 335, 340, 345, 350, 355, 360, 365, 370, 375, 380, 385, 390, 395 or 400°C. The pressure during hydrotreatment can be between 4 and 20 MPa. The pressure can be, for example, from 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 MPa to 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 MPa.

[0072] In one embodiment, particularly in the case of HDO, the weight hourly space velocity (WHSV) used is between 0.25 and 3.0 h , depending on the hydrogen consumption. -1 , preferably 0.7 to 3.0 h -1 , more preferably 1.0 to 2.5 h -1 , and most preferably 1.0 to 2.0 h -1 The hydrogen gas flow rate, particularly in the case of HDO, may be in the range of 350 to 1500 Nl H2 / l feed, more preferably 350 to 900 Nl H2 / l feed, most preferably 350 to 750 Nl H2 / l feed, for example 350 to 500 Nl H2 / l feed.

[0073] Hydrotreating catalysts typically include at least one component selected from IUPAC Groups 6, 8, or 10 of the periodic table. In one embodiment, the catalyst includes at least one of nickel, molybdenum, cobalt, tungsten, and combinations thereof. The catalyst may include, for example, NiMo, CoMo, NiW, or CoNiMo. The catalyst may also include a support including at least one of alumina, silica, zeolite, and combinations thereof.

[0074] In another embodiment, the catalyst comprises at least one of platinum, palladium, nickel and combinations thereof, a zeolite selected from ZSM-12, ZSM-23, SAPO-11, SAPO-41 and fernerite, supported on an alumina and / or silica support. Thus, the hydrotreating catalyst can be a supported Pd, Pt, Ni, NiW, NiMo, CoMo or CoNiMo catalyst, and the support can be a zeolite, zeolite-alumina, alumina and / or silica. The catalyst can be, for example, NiW / AI2O3, NiMo / AI2O3 or CoMo / AI2O3. In particular, the hydrotreating catalyst can be a sulfided NiMo or CoMo catalyst. Even after purification, if the feed contains sulfur, the catalyst does not necessarily have to be sulfided.

[0075] In one embodiment, the hydroprocessing conditions are adjusted to be optimal for the stream in question. In practice, this may mean slight changes in the reaction conditions and catalysts used, depending on the desired end product.

[0076] The hydrotreating step may also include mixing the feedstock refined in this process with another renewable feedstock or several different renewable feedstocks for co-hydrotreating prior to such hydrotreating.

[0077] Hydrodeoxygenation can be carried out, for example, as shown in FI 100248, EP 1741768, WO 2007 / 068795, WO 2016 / 062868 or EP 2155838, as well as using conventional hydrotreating catalysts and hydrogen gas.

[0078] In one embodiment, the hydrodeoxygenation is carried out at reaction conditions including a temperature in the range of 100-500°C, e.g., 250-400°C, or 280-350°C, or 300-330°C; and a pressure in the range of 0.1-20 MPa, e.g., 0.2-8 MPa. The weight hourly space velocity (WHSV) can be in the range of 0.5-3.0 l / h, e.g., 1.0-2.5 l / h, or 1.0-2.0 l / h. The H2 flow rate can be in the range of 350-900 Nl H2 / l feed, e.g., 350-750, or 350-500, in the presence of the hydrodeoxygenation catalyst.

[0079] Advantageously, HDO is carried out to obtain a hydrodeoxidized material containing less than 1 wt-% oxygen.

[0080] A portion of the deoxidizing material may be recycled to the hydrogenation process. Preferably, the ratio of fresh feed or purified material obtained from the previous step to the recycled deoxidizing material is between 2:1 and 20:1.

[0081] In one embodiment, hydrotreating comprises hydrodeoxygenation and hydroisomerization, either simultaneously or sequentially. If performed sequentially, hydrotreating comprises first hydrodeoxygenation and then hydroisomerization.

[0082] The isomerization can be carried out in a conventional hydroisomerization unit, for example as shown in FI 100248, EP 1741768, WO 2007 / 068795, WO 2016 / 062868 or EP 2155838. Hydrogen is added to the hydroisomerization step.

[0083] Both the hydrodeoxygenation step and the hydroisomerization step may be carried out in the same reactor, and even in the same reaction bed. The hydroisomerization catalyst may be a precious metal bifunctional catalyst, such as a Pt-containing commercial catalyst, for example a Pt-SAPO catalyst or a Pt-ZSM catalyst, or may be a non-precious metal catalyst, for example NiW. The hydrodeoxygenation step and the hydroisomerization step may be carried out in the same catalyst bed, for example using a NiW catalyst in both the hydrodeoxygenation and isomerization.

[0084] The isomerization step may be carried out at a temperature of 250-400°C, for example 280-370°C, or 300-350°C. The pressure may be 1-6 MPa, or 2-5 MPa, or 2.5-4.5 MPa. The WHSV may be 0.5-3 l / h, for example 0.5-2 l / h, or 0.5-1 l / h, and the H2 flow rate may be 100-800 Nl H2 / l feed, or 200-650, or even 350-500 Nl H2 / l feed.

[0085] During isomerization, n-paraffins are branched, i.e., to form i-paraffins. Preferably, conditions are selected such that the branches are located at or near the ends of the molecules, thus improving the cold flow properties of the renewable fuel.

[0086] Isomerization is a process used primarily to isomerize hydrodeoxygenated feedstocks, i.e., most thermal or catalytic conversions (e.g., HDO, etc.) result in little or no isomerization (usually less than 5 wt%), but the isomerization process that may be employed in the present process is one that significantly increases the isoparaffin content.

[0087] During the isomerization reaction of n-paraffins to hydrocarbon components, cracking can occur. Therefore, the selection of catalysts and optimization of reaction conditions during the isomerization step are important if cracking is to be avoided. Renewable diesel and naphtha can be produced by cracking during isomerization and can be produced from n-paraffins with long carbon chain length such as renewable base oils. The renewable diesel fuel thus obtained generally has excellent cold flow properties and can be used as winter grade diesel fuel as it is, i.e. 100%, without being mixed with fossil middle distillates. The renewable naphtha component produced by cracking provides the gasoline component.

[0088] Most typically, the renewable hydrocarbons produced by the processes and methods of the present invention are used in renewable fuels, such as gasoline, diesel, or aviation fuel. The renewable hydrocarbons may be used as fuels as such, or they may be used as components of fuels, or as chemicals or feedstocks for chemicals.

[0089] It is to be understood that the disclosed embodiments of the invention are not limited to the particular structures, process steps, or materials disclosed herein, but extend to equivalents thereof that would be recognized by one of ordinary skill in the relevant art. It is also to be understood that the terminology used herein is used only for the purpose of describing particular embodiments, and is not intended to be limiting.

[0090] Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Numerous specific details are provided herein to provide a thorough understanding of embodiments of the invention.

[0091] In this specification, the verbs "to comprise" and "to include" are used as open limitations that do not exclude or require the presence of any unrecited features. Features recited in the dependent claims may be freely combined with each other, unless otherwise expressly stated. Furthermore, it is to be understood that the use of "a" or "an", i.e. the singular form, throughout this specification does not exclude the plural form. EXAMPLES

[0092] Several feedstocks were treated according to the method of the present invention and the efficiency of the treatment with respect to phosphorus and metals was evaluated.

[0093] Feeds and Instructions The feeds used in the study were two dried chicken fat samples (AFP1 and AFP2), two acid oil samples (ASK1 and ASK2) derived from vegetable oil soapstock, and five brown grease samples (BG1, BG2, BG3, BG4), four of which had been centrifuged (Hettich Rotanta centrifuge, 60°C, 4300 rpm, 20 min) to reduce the moisture content to less than 1 wt-% (marked "(C)").

[0094] The feed may contain both solid impurities (precipitates) and dissolved impurities. Solids in the feed are considered inert, so only the dissolved impurities are considered in the elementary charge determination.

[0095] After filtration through a 2 μm filter, the feed was analyzed for phosphorus and metals to determine the amount of dissolved impurities. The elementary charge Q was calculated using formula (I) based on the phosphorus and metal impurity concentrations of the feed, i.e., dissolved impurities. Thus, the net elementary charge (mmol / kg) is the charge of the feed before treatment. The concentrations of dissolved phosphorus and metals were analyzed from all samples by first digesting the sample with acid in a microwave oven to obtain a clear water / acid matrix (visually assessed), then diluting it to a known volume and analyzing it against an acid-based calibration using ICP-MS / MS (tandem inductively coupled plasma mass spectrometry).

[0096] The feed was treated by heat treatment (HT) as it was without balancing the elementary charge as a comparative example, and after balancing the elementary charge by mixing AFP or ASK or phosphorus-containing chemicals with negative net elementary charges of phosphorus and metals and BG or metal-containing chemicals with positive net elementary charges of phosphorus and metals to obtain a balanced feed with an elementary charge close to zero (-10 to +16.2 mmol / kg in the examples).

[0097] The metal-containing chemicals used were Na-stearate (Alfa Aesar), Ca-stearate (Sigma Aldrich), Fe-stearate (TCIEurope), NaOH (Emsure Merck Germany), Ca(OH)2 (Sigma Aldrich), KOH (Emsure Merck Germany). The phosphorus-containing chemicals used were phosphoric acid (PA, Merck Switzerland) and soy lecithin (PL, Millipore Merck Germany). The amount of chemicals required to balance the charge of the feed was calculated by formula (I) and the respective amounts were added to the feed sample, mixed well, and stirred at 70°C for 30 min. The feed was left at 70°C overnight (~16-23 h) to completely dissolve the chemicals (hydroxide / stearate / acid / lecithin) in the oil.

[0098] Heat treatment (HT) was performed by heating 600 g of feed in a Parr Instruments 1 L stirred autoclave reactor under 500 rpm agitation. The feed was heated to 280°C (balance pressure), held at 280°C for 30 min, and then cooled to about 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 corresponds approximately to a 45 min treatment at 280°C in a tubular reactor. The heat-treated products were subjected to filtration (F) through 2 μm filter paper at 85°C for analysis of dissolved impurities (performed as above) or bleaching (BL) with 2000 mg citric acid / kg sample. After addition of citric acid at 85°C and agitation, 1 wt-% bleaching earth was added and agitated, after which the samples were vacuum dried and filtered at 105°C. Conditions were the same for all bleaching tests. As a comparison, a portion of the non-cooked feed was also subjected to bleaching.

[0099] In all tables with results, phosphorus and metals are given as dissolved phosphorus and dissolved metals in mg / kg. The net elementary charge is the net elementary charge Q given by equation (I) (after converting the concentrations to mmol / kg) in mmol / kg.

[0100] result Unbalanced Feed Results The results for the unbalanced feed, or reference sample, are shown in Table 1. The results show that the AFP and ASK samples had a negative elementary charge resulting in phosphorus (P) in the HT+BL product greater than 10 ppm. The BG samples had a positive elementary charge resulting in high metals in the HT+F product and often also in the HT+BL product. Metals are the sum of Na, Mg, K, Ca, and Fe for all results.

[0101] [Table 1]

[0102] Balanced Feed Results - Balanced by Feed Blend Tables 2, 3 and 4 show the results of a series of tests mixing different ratios of different ASK (negative charge elementary) and different BG (positive charge elementary). Comparing the bleaching results of the non-heat treated sample (BL) with the heat treated sample (HT+BL), it is clear that treating the feed with HT prior to BL increases the impurity removal during bleaching.

[0103] Comparing the HT+BL results of different feed blends with different elemental charges, it is clear that the closer the elemental charge was to zero, the better the overall purification results (lower phosphorus and metals). For each mixture, one combination was optimal for removing both dissolved phosphorus and metals, namely, 50% ASK1 + 50% BG4 blend (1.4mmol / kg net charge), 50% ASK1 + 50% BG3 blend (1.6mmol / kg net charge), and 90% ASK1 + 10% BG2 blend (-1.2mmol / kg net charge). The results of the heat treated and filtered samples (HT+F) also showed the same trend, although the impurity levels were higher than the bleached products.

[0104] Figure 1 shows the percent conversion of dissolved phosphorus to solid phosphorus compounds for filtered intermediate samples taken during heat treatment of ASK1, BG4, and their blends. Filtration was performed with 2 μm filter paper as above. % Phosphorus Removal = ((Dissolved phosphorus in feed) - (Dissolved phosphorus in filtered HT sample)) / (Dissolved P in feed). "250C" refers to the sample taken from the reactor when the temperature reached 250°C (about 30 min from start). "280C / 0 min" refers to the sample taken when the reactor temperature reached 280°C (about 45 min from start). "280C / 15 min" refers to the sample taken after 15 min at 280°C (about 60 min from start). "280C / 30 min" refers to the sample taken after 30 min at 280°C (about 75 min from start). The bottom curve, starting at about 30%, is for ASK1 alone. The second curve, starting at about 62%, is for a mixture of 65% ASK1 and 35% BG4. The third curve, starting at about 72%, is for BG4 alone, and the top curve, starting at about 85%, is for a mixture of 50% ASK1 and 50% BG4.

[0105] The results in Figure 1 show that the dissolved phosphorus conversion (comparison of dissolved phosphorus concentration in feed and product) increases with increasing treatment time. For the equilibrated feed (ASK1 50% + BG4 50%), the dissolved phosphorus conversion is higher than for the non-equilibrated feed, and the equilibrated feed can reach very high dissolved phosphorus conversion (>95%) at lower treatment severity (lower temperature and shorter time).

[0106] [Table 2]

[0107] [Table 3]

[0108] [Table 4]

[0109] Table 5 shows the results for various charge-balanced feedstock blends (charge-3.7 to 1.8 mmol / kg, unbalanced ASK / AFP-33 to -13 mmol / kg). Heat treated and bleached (HT+BL) products have significantly lower phosphorus (0.5 to 1.7 ppm) and metals (0.4 to 3.7 ppm) concentrations, thus showing a clear improvement over the results of the unbalanced feedstocks processed individually (Table 1).

[0110] [Table 5]

[0111] Equilibration Feed Results - Equilibration by Chemical Addition The results for equilibration treatment of AFP and ASK with metal-containing chemicals are shown in Table 6. Impurities in the HT+BL products of the equilibrated feed are significantly lower in all cases than after treatment of the unequilibrium feed.

[0112] [Table 6]

[0113] Table 7 shows the results for BG equilibrated with phosphorus-containing chemicals. Impurities in the HT+BL products of the equilibrated feed are significantly lower in all cases than after treatment of the unequilibrium feed. When phosphoric acid (PA) was added, the net charge was calculated based on the dissolved phosphorus in the feed and the phosphorus concentration added with PA.

[0114] [Table 7]

[0115] The refined feedstock was then subjected to hydrotreatment.

Claims

1. A method for producing renewable hydrocarbons from an oxygen-containing renewable feedstock, wherein the feedstock contains dissolved impurities selected from phosphorus-containing impurities and impurities containing at least one metal, and the feedstock further contains at least one triglyceride and a free fatty acid, and the method is a) A step of obtaining a net elementary charge Q1 based on phosphorus and at least one metal in a first feedstock; b) A step of mixing the first feedstock with an elementary charge equilibrium component to obtain a purified feedstock, wherein the purified feedstock has a net elementary charge Qt based on phosphorus and at least one metal in the range of -5 to 15 mmol elementary charge / kg of purified feedstock; c) A step of heat-treating the purified feedstock at a temperature of 180 to 400°C to precipitate the phosphorus and the compound containing the at least one metal; d) a step of removing the resulting precipitate compound containing the at least one metal and the phosphorus in order to obtain a purified feedstock; and e) A step of subjecting the purified feedstock to hydrogenation using a catalyst sensitive to at least one of the impurities. A method that includes this.

2. The method according to claim 1, wherein the charge elementary equilibrium component is a second feed having a net charge elementary Q2 based on the phosphorus and the at least one metal, which is electrically opposite to the net charge elementary Q1 based on the phosphorus and the at least one metal in the first feed.

3. The method according to claim 1, wherein the net elementary charge Q based on the phosphorus and the at least one metal is obtained by formula (I). [Math 1] (Here C P This is the dissolved phosphorus concentration in the feedstock, expressed as mmol / kg of feedstock. Q P This is the elementary charge of dissolved phosphorus in the feedstock, C Mi This is the concentration of dissolved metal i in the feedstock, expressed as mmol / kg of feedstock. Q Mi This is the elementary charge of the dissolved metal i in the feedstock, i is the number of dissolved metals to consider.

4. The method according to claim 1, wherein the dissolved metal present in an amount of at least 1 ppm by weight is taken into consideration in formula (I).

5. The method according to claim 3 or 4, wherein the dissolved metal is selected from sodium, potassium, magnesium, calcium, iron, and mixtures thereof.

6. The method according to claim 1, wherein the charge elementary equilibrium component is selected from a metal-containing compound that can provide a metal cation and a phosphorus-containing compound that can provide a phosphorus anion.

7. The method according to claim 6, wherein the charge elementary equilibrium component is selected from sodium hydroxide, sodium soap, potassium hydroxide, potassium soap, calcium hydroxide, calcium soap, magnesium hydroxide, magnesium soap, iron hydroxide, iron soap, and mixtures thereof, as well as from phosphoric acid, phospholipids, and mixtures thereof.

8. The method according to claim 1, wherein the purification heat treatment is carried out at a temperature of 180 to 310°C.

9. The method according to claim 8, wherein the purification heat treatment is carried out at a temperature of 200 to 290°C.

10. The method according to claim 1, wherein the purification and heat treatment is carried out in the presence of a maximum of 1 wt-% of water.

11. The method according to claim 1, wherein the purification heat treatment is carried out for 1 minute to 3 hours, preferably 15 minutes to 3 hours.

12. The method according to claim 1, wherein the removal of the precipitated compound formed in step d) is carried out by at least one method selected from filtration, sedimentation, centrifugation, washing with water, degumming, and bleaching.

13. The hydrogenation treatment includes hydrogenation deoxygenation and isomerization, and is performed at a temperature in the range of 250 to 400°C, a pressure in the range of 1 to 2 MPa, and 350 to 1500 NlH. 2 The method according to claim 1, wherein a hydrogen flow rate in the range of / l feed is used.

14. The method according to claim 1, wherein the catalyst comprises at least one of nickel, molybdenum, cobalt, tungsten, and combinations thereof.

15. The method according to claim 14, wherein the catalyst comprises NiMo, CoMo, NiW, or CoNiMo.

16. The method according to claim 14 or 15, wherein the catalyst comprises a carrier containing at least one of alumina, silica, zeolite, and combinations thereof.

17. The method according to claim 1, wherein the catalyst comprises at least one of platinum, palladium, nickel and combinations thereof, and a zeolite selected from ZSM-12, ZSM-23, SAPO-11, SAPO-41 and Fernerite, supported on an alumina and / or silica support.

18. The method according to claim 1, wherein the first feedstock and an optional second feedstock comprises at least one of animal fats, animal oils, vegetable fats, vegetable oils, fish fats, fish oils, microbial oils, waste fats, waste oils, residue fats, residue oils, and sludge derived from vegetable oil production.

19. The first feedstock and an optional second feedstock include acidified soap stock, chicken fat, dried rendered chicken fat, brown grease, used cooking oil, tall oil, tall oil fraction, crude tall oil, tall oil pitch, palm oil waste sludge, crude palm oil, palm oil, palm seed oil, palm fatty acid distillate, babassu oil, carinata oil, coconut butter, muscat butter oil, sesame oil, corn oil, poppy seed oil, cottonseed oil, soybean oil, laurel seed oil, and jatrov. The method according to claim 18, comprising at least one of the following: oat oil, palm kernel oil, camelina oil, archaeal oil, bacterial oil, fungal oil, protozoan oil, algal oil, seaweed oil, mustard seed oil, halophilic bacteria-derived oil, soybean oil, technical corn oil, rapeseed oil, coriander oil, canola oil, sunflower oil, hemp seed oil, olive oil, linseed oil, mustard oil, peanut oil, castor oil, coconut oil, lard, animal fat, marine animal oil, used bleached clay oil, lignocellulose-based feed, or mixtures thereof.

20. The method according to claim 1, wherein the renewable hydrocarbon is a renewable fuel and fuel component.

21. The method according to claim 20, wherein the renewable fuel is gasoline, diesel, or aviation fuel.

Images