Method for removing impurities in raw materials

Abstract

The present invention relates to a process and apparatus for removing one or more impurities from a feedstock, the process comprising the step of contacting the feedstock with a protective bed comprising a porous material to provide a purified feedstock; wherein the porous material comprises at least 80% by weight of magnesium aluminate spinel (MgAl2O4), titanium dioxide (TiO2) or a mixture thereof; and the total pore volume of the porous material measured by a mercury intrusion method is 0.50-0.90 ml / g. The invention also envisages a method and an apparatus wherein the guard bed comprises a porous material of at least 80% by weight SiO2.

Description

[0001] The present invention relates to a method and apparatus for removing one or more impurities, such as phosphorus (P), from a feedstock, such as a renewable feedstock, by contacting the feedstock with a guard bed comprising a porous material, such as magnesium aluminum spinel (MgAl2O4), titanium dioxide (TiO2) or a mixture thereof. Optionally, the porous material is silicon dioxide (SiO2).

[0002] Renewable fuels can be produced from a variety of sources, including animal fats and vegetable oils, as well as tall oil, pyrolysis oils, and other non-food compounds. Before feedstocks derived from renewable organic materials can be used in conventional automobile engines, aviation turbines, marine engines, or other engines, and distributed using existing fuel infrastructure, it is desirable to convert the materials into hydrocarbons similar to those found in petroleum-derived transportation fuels. To this end, one established approach is to convert vegetable oils into normal alkanes in the gasoline, jet fuel, or diesel boiling range using a hydrotreating process.

[0003] In a hydroprocessing process, renewable organic materials are reacted with hydrogen at high temperature and pressure in a catalytic reactor.

[0004] A particular problem with feedstocks such as renewable feedstocks is that they contain impurities such as phosphorus- or silicon-containing substances. Phosphorus-containing substances can be present in the form of phospholipids, such as lecithin from seed oils. Waste lubricating oils may also contain substances such as zinc dialkyl dithiophosphate (ZDDP), which is used as an anti-wear additive in such lubricants. Phosphorus (P) quickly deactivates conventional hydroprocessing catalysts and greatly shortens the life cycle of the catalyst. Refineries processing renewable feedstocks are forced to load more materials to protect hydroprocessing catalysts compared to fossil fuel-based refining processes. These units typically pre-treat the feedstock with detergents and / or adsorbents to reduce P from 10-20 ppm to 1-2 ppm, but even at 1-2 ppm, protective materials still need to be used.

[0005] Therefore, whether using only renewable materials as feedstock or a blend of renewable materials with fossil fuels (i.e. co-processing), refineries processing renewable materials have consistently expressed the need for better protective materials, especially for P capture, to prevent pressure drop and bulk catalyst deactivation. It is therefore crucial to reduce or remove (if possible) impurities, especially phosphorus-containing species, before the feedstock reaches the bulk catalyst.

[0006] The concept of "guard beds" in catalytic processes is well known. For example, in U.S. Pat. No. 5,879,642, an upstream catalyst bed is used as a guard catalyst bed to remove a large portion of impurities from a hydrocarbon feed stream to extend the life of one or more catalyst beds located below (downstream) the guard catalyst bed.

[0007] US 9,447,334 (US 2011 / 138680) discloses a process for converting a feedstock by pretreating a feedstock derived from a renewable source, wherein upstream of the hydrotreating step, an intensive pretreating step is performed to eliminate foreign elements (e.g. phosphorus) that are insoluble under the hydrotreating conditions. This step comprises using an adsorbent that is free of catalytic material (free of catalytic metals) and has a high surface area (e.g. 140 m 2 / g) and a high total pore volume (e.g. 1.2 ml / g).

[0008] US2004 / 077737 discloses a catalyst for Fischer-Tropsch synthesis comprising 3-35 wt% cobalt supported on alumina, the surface area of ​​the alumina support being less than 50 m 2 / g and / or at least 10% α-alumina. Cobalt (Co) is suitably combined with a metal promoter Re or Pt. Specifically, when Co is promoted by Re or Pt, the content of Co in the catalyst is 5% by weight or more. When only Co is used in the catalyst, its content is 12% by weight or more.

[0009] US 4,510,092 discloses a process for the continuous hydrogenation of fatty materials, in particular liquid vegetable oils, using a nickel-supported α-alumina catalyst having a surface area of ​​less than 10 m 2 / g, micropore volume is less than 0.1ml / g, and macropore volume is less than 0.6ml / g, preferably less than 0.3ml / g. Micropore volume refers to pores with a diameter less than about The total volume of pores with a diameter greater than about The total volume of the pores. The nickel content is relatively high, i.e. 1-25%.

[0010] US 4,587,012 discloses a method for upgrading hydrocarbon streams to remove metallic impurities such as nickel, vanadium and iron, using a catalyst containing more than 80% alpha-alumina. The pore volume (PV) of the catalyst material is only about 500 ml / kg (0.5 ml / g), and no more than 10% are macropores, i.e., pores with a radius > (Diameter> )’s PV does not exceed 10%.

[0011] Conventional and commercially available guard bed materials for P capture are in the form of catalysts with low metal content supported on a high pore volume gamma-alumina support to provide hydroprocessing activity.

[0012] Typically, the use of metals in guard materials, especially metals with hydroprocessing activity such as molybdenum or nickel, can lead to undesirable coking, which can cause plugging of the guard bed and induce unfavorable pressure drops. Coking can be induced by excessive metal content or excessive activity caused by promoters due to insufficient hydrogen around the catalyst and high temperatures caused by the exothermic reaction.

[0013] WO 2022008508 of the applicant discloses a phosphorus guard bed for a hydroprocessing system, the phosphorus guard bed comprising a porous material comprising α-alumina and optionally one or more metals selected from Co, Mo, Ni, W and combinations thereof.

[0014] Despite recent advances in this area, there is still a need to develop more materials, particularly porous materials for guard beds, to remove impurities such as P while reducing coking levels in the porous materials, particularly for feedstocks containing significant amounts of renewable materials, including feedstocks with 100% renewable materials, i.e., 100% renewable feeds.

[0015] Therefore, according to the first aspect of the present invention, in a first general embodiment, a method for removing one or more impurities from a raw material is provided, the method comprising the step of contacting the raw material with a guard bed comprising a porous material, thereby providing a purified raw material; wherein the porous material comprises at least 80 weight % of the following components: magnesium aluminate spinel (MgAl2O4), titanium dioxide (TiO2) or a mixture thereof; and the total pore volume of the porous material as measured by mercury intrusion is 0.50-0.90 ml / g.

[0016] Mercury porosimetry was performed according to ASTM D4284.

[0017] It has been found that these porous materials can effectively capture phosphorus in renewable feedstocks while limiting coking of the porous materials to acceptable levels.

[0018] Furthermore, the hydroprocessing unit of the process or plant has a longer life cycle.

[0019] As used herein, the term "comprising" also includes "consisting of", ie, "consisting of.

[0020] As used herein, the term "suitably" means "optionally", ie an optional embodiment.

[0021] As used herein, the terms "invention" or "present invention" are used interchangeably with "application" or "this application," respectively.

[0022] As used herein, the term "first aspect" or "the first aspect of the invention" refers to a method according to the invention. The term "second aspect" or "the second aspect of the invention" refers to an apparatus (system) according to the invention.

[0023] Additional definitions of the present application are provided in sections relevant to embodiments of the invention.

[0024] Suitably, the porous material comprises at least 90 wt % or at least 95 wt %, for example 96 wt %, 97 wt %, 98 or 98.5 wt %, 99 or 99.5 wt % or 100 wt % MgAl 2 O 4. Thus, in one embodiment, the porous material may also be high purity MgAl 2 O 4.

[0025] As used herein, the term "high purity" refers to at least 98.5% by weight, such as 99% by weight, 99.5% by weight, or 100% by weight.

[0026] The balance of the porous material (to 100 wt%) can be provided by additives, such as silicon dioxide (SiO2). For example, ≥80 wt% of the porous material is MgAl2O4, and ≤20 wt% is an additive, such as SiO2. For example, ≥80 wt% of the porous material is TiO2, and ≤20 wt% is an additive, such as SiO2. For example, ≥80 wt% of the porous material is a mixture of MgAl2O4 and TiO2, and ≤20 wt% is an additive, such as SiO2.

[0027] It should be understood that the term "additive" refers to materials other than MgAl2O4 and / or TiO2 in the process material, which are used as the balance (to 100 wt%) of the porous material. Therefore, the additive (e.g., one or more additives) accounts for ≤20 wt% of the porous material.

[0028] Additives such as SiO2 can improve the stability of the porous material, i.e., be less sensitive to process operating temperatures such as 100-400°C, optionally in the presence of a reducing agent such as hydrogen. In addition, providing, for example, SiO2 can reduce the cost of the porous material, thereby reducing process costs, since additives such as SiO2 are generally cheaper than MgAl2O4 and / or TiO2.

[0029] Suitably, the porous material comprises at least 90 wt % or at least 95 wt %, such as 96 wt %, 97 wt %, 98 wt % or 98.5 wt %, 99 wt % or 99.5 wt % or 100 wt % TiO 2. Thus, in one embodiment, the porous material may also be high purity TiO 2, such as 100 wt % anatase.

[0030] In one embodiment, the porous material is 100 wt % of said mixture of MgAl2O4 and TiO2.

[0031] In one embodiment, the mixture of MgAl2O4 and TiO2 is 30-70 wt% MgAl2O4 and 70-30 wt% TiO2. Therefore, the mass ratio of MgAl2O4 to TiO2 is 30:70 to 70:30.

[0032] For example, the porous material is a mixture of 100 wt% MgAl2O4 and TiO2, wherein MgAl2O4 is 30-70 wt% and TiO2 is 70-30 wt%. For example, the porous material is 50 wt% high-purity MgAl2O4 and 50 wt% high-purity TiO2. For example, the porous material is 35 wt% high-purity MgAl2O4 and 65 wt% high-purity TiO2.

[0033] A mixture of MgAl2O4 and TiO2, such as a 100 wt% mixture of MgAl2O4 and TiO2, wherein MgAl2O4 is 30-70 wt% and TiO2 is 70-30 wt% as previously described, wherein MgAl2O4 and TiO2 are prepared or provided as described above, can also achieve high P capture.

[0034] The porous material comprising at least 80% by weight of MgAl2O4 can be purchased externally, for example, as MgAl2O4 powder, or in the form of particles, such as flaky pellets (e.g., flaky pellets having a four-leaf shape). The MgAl2O4 powder can, for example, contain 99.5% MgAl2O4, i.e., high-purity MgAl2O4. The porous material comprising at least 80% by weight of TiO2 can, for example, be purchased externally as TiO2 powder, or in the form of particles, such as flaky pellets (e.g., flaky pellets having a four-leaf shape). The TiO2 powder can, for example, contain 99.5% TiO2, i.e., high-purity TiO2.

[0035] Suitably, the method further comprises a pre-step for preparing the porous material, which is carried out by providing a starting material (i.e. a precursor material) comprising MgAl2O4 and calcining it in air at 850-1050°C (e.g. 900-1000°C, e.g. 900, 950 or 1000°C), optionally for 1-3 hours, e.g. 2 hours.

[0036] Suitably, the starting material is high purity MgAl2O4, for example as said externally sourced MgAl2O4 powder, or as particles such as pellets, for example flake-like pellets having a quadrilobate shape.

[0037] It has been found that for MgAl2O4, when the calcination temperature is below 800°C, the total pore volume (PV) becomes too high, i.e., above 0.90 ml / g (>900 ml / kg), while when the calcination temperature is above 1050°C, the PV becomes too low, i.e., below 0.5 ml / g (<500 ml / kg). Outside 500-900 ml / kg, low P capture is observed.

[0038] Suitably, the method comprises directly providing the starting material as said MgAl2O4.

[0039] "Directly" means that there is no prior step of calcination or heat treatment prior to providing the MgAl2O4.

[0040] Suitably, the method further comprises a pre-step for preparing the porous material, which is carried out by providing a starting material (i.e. a precursor material) comprising TiO2 and calcining it in air at a temperature below 500°C, such as 250-450°C, such as 300, 350 or 400°C, optionally for 1-3 hours, such as 2 hours.

[0041] Suitably, the method comprises directly providing the starting material as said TiO2.

[0042] "Directly" means that there is no prior step of calcination or heat treatment before providing the TiO2.

[0043] Thus, the method may comprise directly providing the starting material as said MgAl2O4, TiO2, or a mixture thereof.

[0044] Again, "directly" means that there is no preceding step of calcination or heat treatment prior to providing the MgAl2O4, TiO2 or mixtures thereof.

[0045] As used herein, the term "starting material" or interchangeably "precursor material" applies to MgAl2O4 or TiO2 or a mixture thereof.

[0046] For MgAl2O4, the term "starting material" refers to, for example, an externally purchased material, such as MgAl2O4 powder or MgAl2O4 particles, which is subsequently calcined in air at 850-1050°C (e.g., 900, 950 or 1000°C), optionally for 1-3 hours (e.g., 2 hours), to become MgAl2O4, which is provided as the at least 80 wt% guard bed porous material. The starting material may also be provided directly as the at least 80 wt% guard bed porous material without calcination or heat treatment.

[0047] For TiO2, the term "starting material" refers to, for example, an externally purchased material, such as TiO2 powder or TiO2 particles, which is subsequently calcined in air at 500°C, such as 250-450°C or less, optionally for 1-3 hours, such as 2 hours, to become TiO2, which is provided as the at least 80% by weight guard bed porous material. The starting material can also be directly provided as the at least 80% by weight guard bed porous material without calcination or heat treatment.

[0048] It has been found that for TiO2, calcination at low temperature (i.e., 500°C) or without calcination or heat treatment, PVs of 0.50 ml / g or higher, such as 600, 700 ml / g, can be obtained, thus facilitating P capture. In contrast to MgAl2O4, increasing the calcination temperature of TiO2 above 500°C results in PVs below 0.50 ml / g. For example, calcination at 550°C for 2 hours in air results in a PV of 0.44 ml / g; calcination at 750°C for 2 hours in air results in a PV of 0.240 ml / g. At these low PV values ​​(below 0.50 ml / g), low P capture is observed.

[0049] Therefore, more specifically, in one embodiment, the method further comprises:

[0050] i-1) a pre-step for preparing MgAl2O4 in the porous material, by providing a starting material comprising MgAl2O4 and calcining it in air at 850-1050°C (e.g. 900-1000°C, e.g. 900, 950 or 1000°C), optionally for 1-3 hours, e.g. 2 hours;

[0051] or

[0052] i-2) directly providing a starting material as the MgAl2O4;

[0053] and / or

[0054] ii-1) a pre-step for preparing TiO2 in the porous material, by providing a starting material comprising TiO2 and calcining it in air at a temperature below 500°C, such as 250-450°C, such as 300, 350 or 400°C, optionally for 1-3 hours, such as 2 hours;

[0055] or

[0056] ii-2) directly providing a starting material as the TiO2.

[0057] In particular, optimal P capture is observed when said calcination in step i-1) is at 900-1000°C and said calcination in step i-2) is below 500°C or calcination is avoided, as shown in the Examples section below.

[0058] In one embodiment, the titanium dioxide (TiO2) is at least 99.9 wt% anatase. It has been found that when anatase is ≤ 99.8 wt%, for example, when the TiO2 is 99.8 wt% anatase and 0.2 wt% rutile, the pore volume becomes too low (less than 0.50 ml / g) to properly capture P. For example, when the TiO2 starting material is calcined in air at above 600°C for 1-3 hours (e.g., 2 hours), the TiO2 will appear in the form of rutile and account for 0.2 wt% or more of the TiO2. For example, calcined at 650°C for 2 hours, the rutile is 0.2 wt% and the pore volume is 0.390 ml / g; calcined at 750°C for 2 hours, the rutile is 1.1 wt% and the PV is 0.240 ml / g.

[0059] In one embodiment, the porous material includes one or more metals selected from Co, Mo, Ni, W and combinations thereof; and the content of the one or more metals is 0.25-20 wt %. For example, the content of the one or more metals is 0.25-15 wt %, 0.25-10 wt %, or 0.25-5 wt %.

[0060] Without being bound by any theory, it can be found that the present application reduces the surface reactivity of the porous material to P substances compared to traditional γ-alumina-based materials - so that P is not only captured on the surface of the porous material - but is at least comparable to the α-alumina materials disclosed in WO 2022008508 of the above-mentioned applicant (see the Examples section). At the same time, the porous material allows better penetration of the feed (especially renewable feed), thereby allowing better penetration of the P substance. In addition, it is also found that the use of one or more metals with hydroprocessing activity can reduce coking on the porous material, which, again, without being bound by any theory, can be attributed to the metal (such as Mo) blocking the remaining acid sites, or to some small hydrogenation activity of the porous material when the metal is present.

[0061] In one embodiment, the porous material has a diameter of 1-150 m 2 / g of BET surface area.

[0062] BET surface area is suitably measured according to ASTM D4567-19, ie, single point surface area determination by the BET equation.

[0063] It has been found that reducing the BET surface area can reduce coking, especially for TiO2 and MgAl2O4. BET surface areas above 150 m 2 / g will result in more coking.

[0064] Suitably, the BET surface area is 60-120 m 2 / g, for example 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115m 2 / g.

[0065] In one embodiment, the porous material has a MgAl2O4 content of 50-150 m 2 / g BET surface area, for example 60, 70, 80, 90, 100, 110, 120, 130, 140 m 2 / g.

[0066] In one embodiment, the porous material has a TiO2 content of 100-150 m 2 / g BET surface area, such as 110, 120, 130, 140 m 2 / g.

[0067] As used herein, the degree of coking, or simply coking, refers to the carbon content of a porous material after use.

[0068] In one embodiment, the MgAl2O4 in the porous material is at least 90 wt% MgAl2O4, such as at least 95 wt% MgAl2O4, at least 99 wt% MgAl2O4, or 100 wt% MgAl2O4, and has a pore size distribution (PSD) wherein at least 60 vol% (e.g., at least 70 vol% or at least 80 vol%) of the total pore volume is located at pores with a radius below For example, in holes with radii as low as or as low as hole.

[0069] For MgAl2O4, the radius is equal to or greater than or equal to or greater than Larger holes can be used for P capture, while radii below The smaller pores allow the one or more metals in the porous material to be better available for providing hydroprocessing activity. The porous material has, for example, a bimodal pore system, wherein in particular the smaller pores (pore radius less than ) increases the possibility of providing hydroprocessing activity to porous materials.

[0070] In one embodiment, the TiO2 in the porous material is at least 90 wt% TiO2, such as at least 95 wt% TiO2, at least 99 wt% TiO2, or 100 wt% TiO2, and has a pore size distribution (PSD) wherein at least 90 vol% (e.g., at least 95 vol%) of the total pore volume is located at pores with a radius below For example, in holes with radii as low as or as low as holes, such as And the average pore radius is

[0071] The TiO2 in the porous material has a unimodal pore system, and surprisingly, the pore structure is mainly composed of small pores (with an average pore radius of ) can achieve P capture at least comparable to that of MgAl2O4, while increasing the possibility of providing hydroprocessing activity to the porous material. For P capture, it does not appear that larger pores, such as those with radii exceeding or hole.

[0072] The protective material, i.e. the porous material, has a certain (albeit low) hydroprocessing activity to avoid coking and high exothermicity when the feed is contacted with the downstream main catalyst bed for hydroprocessing. The most reactive molecules in the feed are converted, thereby reducing the risk of gelling due to excessive temperatures. Therefore, a trade-off is achieved by the present invention: the absence of metal may lead to coking in the material; too much metal activity may lead to coking and gelling due to excessive exothermicity. Low metal content, such as 15 wt% Mo, 10 wt% Mo, 5 wt% Mo, or lower, such as 3 wt% Mo, 1 wt% Mo or 0.5 wt% Mo, appropriately within the corresponding ranges described below, seems to just balance these two deactivation effects. In addition, partial preheating is also achieved before the feed reaches the bulk catalyst (i.e. the downstream hydroprocessing catalyst), thereby improving the energy efficiency of the method or equipment.

[0073] Thus, in one embodiment, the one or more metals include Mo in an amount of 0.5-15 wt %, such as 0.5-10 wt %, or 0.5-5 wt %, or 0.5-3 wt %, such as 0.5-1.5 wt % or 0.5-1 wt %, such as 0.7 or 0.9 wt %, or 1-2 wt %. Optionally, 0.1-5 wt %, such as 0.1-3 wt %, 0.1-1 wt %, 0.1-0.5 wt %, or 0.1-0.2 wt % of Ni, Co, and W are provided. Optionally, the porous material is free of Co and / or W. For example, the porous material includes 0.05-5 wt % of Mo, so Mo is the one or more metals. For example, the porous material includes 0.5-0.5 wt % of Ni. The content of Ni is much lower than that of conventional materials. Thus, for example, the porous material also includes 0.5-5 wt % of Mo and 0.05-0.5 wt % of Ni, wherein Mo and Ni are the one or more metals.

[0074] Thus, in one embodiment, the porous material is free of Co and / or W, and further comprises 0.05-0.5 wt. % Ni.

[0075] Therefore, it should be understood that in a specific embodiment, at least one or more metals are Mo. In another specific embodiment, one or more metals are Mo and Ni. Therefore, the porous material does not include one or more metals selected from Co, W. For example, the porous material may include 0.5-1.5 wt % Mo (e.g., 1 wt % Mo) and 0.1-0.2 wt % Ni. Due to the low surface area of ​​the porous material, the Mo loading (Mo content) is reduced, but by adding, for example, Ni as a promoter, the low metal content can be compensated. In addition, although the surface area of ​​the porous material of the present invention is low, a small amount of molybdenum (e.g., 0.5-3 wt % Mo, e.g., about 1 wt %) can lead to significantly reduced coking formation.

[0076] The present invention does not require the use of any metal to provide P capture, but the addition of Mo can significantly reduce coking and can also achieve the desired effect of achieving an activity gradient in a unit comprising a porous material. In addition, while the addition of Co or Ni as a promoter may be desirable because it will significantly increase activity, this can be very detrimental to downstream hydroprocessing stages that contain at least one hydroprocessing catalyst. More specifically, when processing renewable feedstocks, this can be very detrimental to hydroprocessing / hydrodeoxygenation (HDO) selectivity (yield loss). Although it is ideal to remove oxygen from renewable feedstocks in HDO primarily by removing HO, in particular, nickel levels above about 0.5 wt% can result in undesirable decarboxylation, thereby reducing HDO selectivity.

[0077] Materials catalytically active in hydroprocessing / HDO typically include an active metal (a sulfided base metal such as nickel, cobalt, tungsten and / or molybdenum, but may also include elemental noble metals such as platinum and / or palladium) and a refractory support (such as alumina, silica or titania, or combinations thereof).

[0078] The hydroprocessing conditions include a temperature in the range of 250-400°C, a pressure in the range of 30-150 bar, a liquid hourly space velocity (LHSV) in the range of 0.1-2, optionally with intermediate cooling by using cold hydrogen, feed or product.

[0079] In an embodiment according to the first aspect, at least one metal is in the form of an oxide or a sulfide.

[0080] In an embodiment according to the first aspect, the porous material is an extruded or tabletted particle, and its shape is selected from trilobal, quadrilobal, pentalobal, cylindrical, spherical, hollow (such as hollow ring or hollow cylinder) and combinations thereof. Quadrilobal particles are particularly advantageous because their surface area / volume ratio is improved.

[0081] In one embodiment, the one or more impurities are selected from vanadium-containing impurities, silicon-containing impurities, halogen-containing impurities, iron-containing impurities, phosphorus-containing impurities and combinations thereof; preferably, the one or more impurities are phosphorus (P)-containing impurities. In addition, the process is carried out at high temperature, such as 100-400° C., such as 250-350° C., optionally in the presence of a reducing agent (such as hydrogen).

[0082] In one embodiment, the feedstock is a renewable feedstock, a fossil fuel feedstock, or a combination thereof. Suitably, the feedstock is a renewable feedstock or a combination of a renewable feedstock and a fossil fuel feedstock.

[0083] Thus, in one embodiment, the starting material is:

[0084] i) Renewable origin, obtained from renewable origin raw materials, for example from plants, algae, animals, fish, vegetable oil refining, household garbage, plastic-rich waste, industrial organic waste such as tall oil or black liquor, or from one or more of the following oxygenated compound groups: triglycerides, fatty acids, resin acids, ketones, aldehydes or alcohols, wherein the oxygenated compounds are derived from one or more of biological sources, gasification processes, pyrolysis processes, Fischer-Tropsch synthesis or methanol-based synthesis. The oxygenated compounds may also be derived from other synthesis processes. Some of these raw materials may contain aromatic compounds; in particular products from pyrolysis processes or from waste products such as frying oil. Any combination of the above raw materials is also envisaged.

[0085] The raw materials can also be:

[0086] ii) feedstocks derived from fossil fuels, such as diesel, kerosene, naphtha, vacuum gas oil (VGO), waste lubricating oils, or combinations thereof;

[0087] or

[0088] iii) A feedstock derived from a renewable source according to i) in combination with a feedstock derived from fossil fuels according to ii).

[0089] In the context of the present invention, the terms "renewable source" and "renewable feedstock" or "renewable raw material" are used interchangeably. The terms "fossil fuel-derived feedstock" and "fossil fuel feedstock" are also used interchangeably.

[0090] In one embodiment, the portion of the feedstock derived from renewable sources is 5-60% by weight, such as 10 or 50% by weight. In another specific embodiment, the portion of the feedstock derived from renewable sources is higher than 60% by weight, such as 70-90% by weight.

[0091] In one embodiment, one or more impurities are phosphorus (P) impurities, and the feedstock contains 0.5-1000 ppm of P. The P content may vary significantly depending on the feedstock. For example, the P content in an oil derived from oxygenates from a pyrolysis process (e.g., pyrolysis oil) is 50-60 ppm, or the P content in a feedstock derived from animals (particularly animal fats) is 100-300 ppm or 50-300 ppm, such as 200 ppm. For example, the P content is 400, 500, 600, 700, 800, 900 ppm.

[0092] It should be understood that the ppm unit is based on weight, ie, ppm-wt.

[0093] In one embodiment, the purified feedstock is subsequently processed in a hydroprocessing stage in the presence of a hydroprocessing catalyst. In a particular embodiment, the hydroprocessing stage is located directly downstream, optionally including heating / cooling in between. In another particular embodiment, the hydroprocessing catalyst preferably comprises at least one metal selected from Co, Mo, Ni, W, and combinations thereof.

[0094] According to the first aspect of the present invention, in a second general embodiment, there is provided a method for removing one or more impurities from a raw material, the method comprising the step of contacting the raw material with a guard bed comprising a porous material, thereby providing a purified raw material; wherein the porous material comprises at least 80 wt % silicon dioxide (SiO2), and the total pore volume of the porous material as measured by mercury intrusion porosimetry is 0.90-1.50 ml / g.

[0095] Mercury porosimetry was performed according to ASTM D4284.

[0096] It was also observed that the P capture, although slightly lower than that of MgAl2O4 and TiO2, was able to achieve comparable coking reduction as MgAl2O4 and TiO2, as shown in the Examples section of this application.

[0097] Suitably, the porous material comprises at least 90 wt % or at least 95 wt %, for example 96 wt %, 97 wt %, 98 or 98.5 wt %, 99 or 99.5 wt % or 100 wt % SiO 2 . Thus, in one embodiment, the porous material is high purity SiO 2 .

[0098] The porous material comprising at least 80 wt % SiO2 can be, for example, externally purchased silica powder (silicopowder), or in the form of particles as described above for MgAl2O4 and TiO2. For example, the silica powder can contain 98.5-99 wt % SiO2, i.e. high purity SiO2, with the remainder comprising trace amounts of aluminum oxide, titanium dioxide and iron oxide. For example, the silica powder can also be silica sand.

[0099] In one embodiment, the method further comprises directly providing a starting material, ie a precursor material, as said SiO2.

[0100] In one embodiment, the porous material comprising at least 80 wt. % SiO2 has a total pore volume of 0.90-1.50 ml / g.

[0101] In one embodiment, the porous material has a diameter of 200-350 m 2 / g BET surface area, for example 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340 m 2 / g.

[0102] In a second aspect of the present invention, there is also provided an apparatus (system) for carrying out the method according to any one of the above embodiments.

[0103] It should be understood that any embodiment of the method according to the present invention may be used in conjunction with the apparatus of the present invention, and vice versa. Example

[0104] Table 1 below shows the comparison results of the porous material according to the present invention with the prior art. As is well known in the art, the ignition loss (LOI, wt%) is used to measure the coking of the sample after use, thereby serving as an indicator of the carbon content (C, wt%). The total pore volume (PV) of the fresh sample and the P capture amount (P pickup) after use are shown. No metals such as Mo are added. The test was carried out in an intermittent reactor test, in which a small amount of sample was reacted with a renewable feed in an intermittent reactor at about 300°C in the presence of hydrogen, as shown below:

[0105] Sample preparation:

[0106] The catalyst or support sample was crushed and sieved to a size of 300-600 microns.

[0107] Model materials:

[0108] For 400 grams of raw material, 6.65 grams of lecithin were dissolved in 197 grams of heptane, and then 197 grams of soybean oil were added. The phosphorus content was 800 ppm-wt.

[0109] Testing Procedure:

[0110] 1.5 g of sample and 15 g of feedstock were added to a batch reactor. The reactor was sealed and flushed with nitrogen. After applying 50 bar of hydrogen pressure, the reactor was heated to 320°C (2.5°C / min) and kept at the maximum temperature for 6 minutes. After recovering the sample particles, they were extracted with xylene using a Soxhlet extractor to remove any heavy oil residues and dried under vacuum at 90°C.

[0111] analyze:

[0112] The dried samples were analyzed for carbon using a LECO instrument and for P and Al using XRF analysis as disclosed in the applicant's WO 2022008508.

[0113] The total pore volume (PV) was determined using mercury intrusion porosimetry according to ASTM D4284.

[0114] Table 1

[0115]

[0116] A: 100 wt% MgAl2O4 obtained by calcining the MgAl2O4 catalyst support material at 900°C;

[0117] B: 100 wt% TiO2 (anatase) obtained by calcining the TiO2 catalyst support material below 500°C or without calcination (no heat treatment) - the starting material is directly provided as TiO2;

[0118] C: 100 wt% MgAl2O4 obtained by calcining the MgAl2O4 catalyst support material at 1000°C;

[0119] D (prior art): according to the applicant's WO 2022008508, i.e. a sample based on α-alumina (sample 3, Figures 1-2 therein).

[0120] E: 100% SiO2 - the starting material was provided directly as SiO2.

[0121] *Note: 77.7 g / L is the P capture capacity of the applicant's WO2022008508, which was not intermittently tested as in this application and therefore cannot be directly compared.

[0122] Batch reactor testing shows that A (100% MgAl2O4), B (100 wt% TiO2) and C (100 wt% MgAl2O4), especially samples B and C, are good candidates for guard beds as they are similar to or appear to be even better than sample D in terms of P capture (sample B). Sample D showed a P capture of 5.78 g / L in this batch test and is used herein as a reference porous material, which corresponds to sample 3 of Figures 1-2 of WO 2022008508, which is rich in α-alumina and also contains θ-alumina. Sample D shows higher P capture under industrial relevant conditions, about 600% higher than the reference sample therein (WO 2022008508, sample 1 - reference: >95 wt% γ-alumina). Sample E (100% SiO2) has slightly lower P capture than samples AC, but its carbon content is comparable to sample B.

Claims

1. A method for removing one or more impurities from a feedstock, the method comprising the step of contacting the feedstock with a guard bed comprising a porous material to provide a purified feedstock; wherein the porous material comprises at least 80% by weight of the following components: magnesium aluminum spinel (MgAl2O4), titanium dioxide (TiO2) or a mixture thereof; and the porous material has a total pore volume of 0.50-0.90 ml / g as measured by mercury intrusion porosimetry.

2. The method according to claim 1, wherein in the mixture of MgAl2O4 and TiO2, MgAl2O4 is 30-70 wt% and TiO2 is 70-30 wt%.

3. The method according to any one of claims 1 to 2, wherein the method further comprises: i-1) a preparatory step for preparing MgAl2O4 in the porous material, by providing a starting material comprising MgAl2O4 and calcining it in air at 850-1050°C, for example 900-1000°C, optionally for 1-3 hours; or i-2) directly providing a starting material as the MgAl2O4; and / or ii)-1 Pre-step for preparing TiO2 in the porous material, by providing a starting material, i.e. a precursor material, comprising TiO2, and calcining it in air at a temperature below 500°C, e.g., 250-450°C, optionally for 1-3 hours; or ii-2) directly providing a starting material as the TiO2.

4. The method of claim 1, wherein the titanium dioxide (TiO2) is at least 99.9 wt% anatase.

5. The method according to any one of claims 1 to 4, wherein the porous material comprises one or more metals selected from Co, Mo, Ni, W and combinations thereof; the content of the one or more metals is 0.25-20 wt %, such as 0.25-15 wt %, 0.25-10 wt %, or 0.25-5 wt %.

6. The method according to any one of claims 1 to 5, wherein the porous material has a thickness of 1 to 150 m 2 / g of BET surface area.

7. The method according to any one of claims 1 to 6, wherein the porous material is at least 90 wt% MgAl2O4, such as at least 95 wt% MgAl2O4, at least 99 wt% MgAl2O4 or 100% MgAl2O4, and has a pore size distribution (PSD) wherein at least 60 vol%, such as at least 70 vol% or at least 80 vol% of the total pore volume is located in a region with a radius of In holes with radii as low as or as low as in the hole.

8. The method of any one of claims 1 to 7, wherein the porous material is at least 90 wt% TiO2, such as at least 95 wt% TiO2, at least 99 wt% TiO2 or 100 wt% TiO2, and has a pore size distribution (PSD) wherein at least 90 vol%, such as at least 95 vol%, of the total pore volume is located in pores with a radius of In holes with radii as low as or as low as of the pores; and wherein the average pore radius is 9. The method according to any one of claims 5 to 8, wherein the one or more metals include Mo in an amount of 0.5-15 wt%, such as 0.5-10 wt%, or 0.5-5 wt%, or 0.5-3 wt%, or 0.5-1.5 wt%.

10. The method according to claim 9, wherein the porous material is free of Co and / or W and further comprises 0.05-0.5 wt% Ni.

11. The method according to any one of claims 1 to 10, wherein the one or more impurities are selected from vanadium-containing impurities, silicon-containing impurities, halide-containing impurities, iron-containing impurities, phosphorus-containing impurities and combinations thereof; in addition, the method is carried out at high temperature, such as 100-400° C., optionally in the presence of a reducing agent, such as hydrogen.

12. The method according to any one of claims 1 to 11, wherein the raw material is: i) of renewable origin, obtained from raw materials of renewable origin, for example originating from plants, algae, animals, fish, vegetable oil refining, household waste, waste rich in plastics, industrial organic waste such as tall oil or black liquor, or from one or more of the following oxygenated compounds group: triglycerides, fatty acids, resin acids, ketones, aldehydes or alcohols, wherein the oxygenated compounds originate from one or more of biological sources, gasification processes, pyrolysis processes, Fischer-Tropsch synthesis or methanol-based synthesis; or ii) feedstocks derived from fossil fuels, such as diesel, kerosene, naphtha, vacuum gas oil (VGO), waste lubricating oils or combinations thereof; or iii) A feedstock derived from a renewable source according to i) in combination with a feedstock derived from fossil fuels according to ii).

13. A process according to claim 12, wherein the portion of the feedstock originating from renewable sources is 5-60% by weight, such as 10 or 50% by weight.

14. The method according to any one of claims 1 to 13, wherein the one or more impurities are phosphorus (P)-containing impurities, and the content of P in the raw material is 0.5-1000 ppm.

15. Process according to any one of claims 1 to 14, wherein the purified feedstock is subsequently processed in a hydrotreatment stage in the presence of a hydrotreatment catalyst.

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