A FeS x / layered silicate nanocomposite catalyst and its preparation and application

Abstract

The present invention discloses an FeS x / layered silicate nanocomposite catalyst and its preparation and application. The FeS x / layered silicate nanocomposite catalyst comprises FeS x particles and single-layered silicate disks, and has a structure in which spherical FeS x nanoparticles are highly dispersed and combined on single-layered silicate disks. The layered silicate is dissolved in water to form a colorless and transparent sol under mechanical external force; an iron source and a sulfur source are dissolved in water to form an FeS x precursor solution; the silicate sol and the obtained FeS x precursor solution are mixed under mechanical external force to form a uniform mixed sol; after the obtained mixed sol is subjected to crystallization treatment, the product in the formed gel is separated out, and is fully dried to obtain the FeS x / layered silicate nanocomposite catalyst. The present invention solves the problems such as poor contact with the catalyst during the liquid-phase hydrocracking process of asphaltene, realizes the full conversion of asphaltene by hydrogenation and the recycling of the catalyst, and improves the economy of the suspension bed hydrocracking catalyst.

Description

Technical Field

[0001] The present invention relates to a preparation method of an FeS x / layered silicate nanocomposite catalyst, belonging to the catalyst preparation technology in the technical field of industrial catalysis. Background Art

[0002] In China, the reserves of heavy oil raw materials are abundant. The hydro-upgrading of heavy oil to produce basic oils such as gasoline, diesel, and lubricating oil can not only alleviate the shortage of energy supply in China but also meet the requirements of sustainable development. However, the asphaltene components with high content, complex structure, and high thermal sensitivity bring many difficulties to its hydro-upgrading utilization. At present, the understanding of the microscopic structure of petroleum asphaltenes mainly has three levels, namely the molecular level, the liquid crystal-like aggregate, and the micelle. In recent years, a large number of studies have also been carried out on the upgrading of petroleum asphaltenes. The liquid-phase hydroconversion method of asphaltenes is an effective new conversion route for the hydro-upgrading of asphaltenes. During the hydroconversion process, asphaltenes simultaneously undergo a complex reaction network, mainly including the following two types: one is the hydroconversion of macromolecular asphaltenes into small-molecule substances, generating light hydrocarbon substances such as gas, gasoline, and diesel. This type of reaction plays a positive role in the upgrading and heteroatom removal of asphaltenes; the other is the condensation reaction, which generates coke and ultimately leads to catalyst deactivation, being unfavorable for the reaction and catalysis. Therefore, the development of highly efficient and highly economical asphaltene hydroconversion catalysts will solve the core problems in the hydro-upgrading utilization of heavy oil.

[0003] At present, many middle oil suspension bed hydrocatalysts have been developed in the field of petroleum processing. Chinese patents CN1132910C, CN1133727C, and CN1107712C disclose oil-soluble suspension bed hydrocatalysts. Although these catalysts have good dispersibility, they have the disadvantages of high raw material prices and high catalyst preparation costs. Patents CN1952064A, CN1233798C, CN1243082C, CN1050151C, CN1133725C, CN1482214A, US4637871, US5039392, etc. disclose water-soluble suspension bed hydrocatalysts and their preparation and use methods. The advantages of these catalysts are that the active components of the catalyst are better dispersed and the price is cheap. However, the use process increases links such as predispersion, dehydration, and presulfidation, and the operation cost is greatly increased.

[0004] Iron sulfide catalysts (such as FeS, Fe3S4, and FeS2) have received extensive attention from researchers due to their low price and abundant reserves. The particulate catalysts used in early hydrogenation technologies mainly included low-cost natural minerals such as pyrite, nano-iron, metal waste slag, iron-coal solid powder, and red mud. These catalysts had low hydrogenation activity and high reaction temperatures, resulting in thermal cracking as the main reaction. Moreover, the particle size was in the micron / submicron scale, much larger than the asphaltene cluster size, and could not contact it sufficiently, so the catalytic ability for asphaltene hydrogenation was weak and the reaction was prone to coking. In addition, the solid powder remained in the unreacted heavy raw materials and was difficult to handle. This was the main reason why early technologies were difficult to be industrialized. To improve the catalytic hydrogenation performance of iron sulfide for asphaltene, iron sulfide can be compounded with other materials to prepare special structures and morphologies, and the materials can be nano-sized. Literature (CIESC Journal, 2021, 72, 2849 - 2856), Chinese patents CN103606677A and CN 110085435A reported the compounding of iron sulfide with carbon nanomaterials, graphene, porous carbon and other materials to improve its performance. However, in the above studies, either large-particle pyrite was used as the raw material for compounding, or high-temperature pretreatment was required to obtain the compounded iron sulfide material. In addition, carbon materials were prone to become the coking center of asphaltene during the asphaltene hydrogenation reaction. Therefore, in order to prepare a nano-sized, highly active and highly economical iron sulfide composite catalyst, it is necessary to use appropriate nanomaterials to synthesize the iron sulfide nano-composite catalyst by a one-step low-temperature method. Summary of the Invention

[0005] The present invention provides an FeS x / layered silicate nano-composite catalyst and its preparation and application. The spherical and non-agglomerated FeS x nano-particles in the structure of the composite catalyst are highly dispersed and compounded on a single layered silicate disc, which improves the contact degree between FeSx and asphaltene, and FeS x is low in price, which improves the activity and economy of its asphaltene hydrogenation catalyst, overcomes the above deficiencies of the prior art, and can effectively solve the coking problem caused by the large particle size of the FeS x catalyst and insufficient contact with asphaltene. The present invention creatively uses nano-sized layered silicate to compound with iron sulfide to prepare an FeS x / layered silicate nano-composite catalyst, thus realizing the non-coking full conversion of asphaltene liquid-phase hydrocracking to produce light oil products.

[0006] An FeS x / layered silicate nano-composite catalyst of the present invention comprises FeS x particles and a single layered silicate disc; in terms of structure, it is spherical FeS xHighly dispersed composite of nanoparticles on single-layered silicate disks; spherical FeS x The diameter of the nanoparticles is 1 to 5 nm, without agglomeration; the diameter of a single-layered silicate disk is 1 to 35 nm, and the thickness of a single disk is 0.7 to 2.2 nm.

[0007] An FeS of the present invention x / layered silicate nanocomposite catalyst is prepared by the following steps:

[0008] (1) At least one layered silicate with a particle size of 10 to 100 nm synthesized chemically is dispersed in water, and a colorless and transparent sol is formed under at least one mechanical external force among high-speed shear emulsification, mechanical stirring, magnetic stirring, and manual stirring;

[0009] (2) At least one of ferric nitrate, ferric chloride, ferric sulfate, ferrous chloride, ferric oxalate, ferric acetate, and ferric citrate is used as an iron source, and at least one of soluble sodium sulfide, potassium sulfide, ammonium sulfide, thiourea, thioacetamide, cysteine, and glutathione is used as a sulfur source and dissolved in water to form an FeS x precursor solution; the molar ratio of Fe / S in the precursor solution is 1:1 to 1:4.

[0010] (3) The silicate sol obtained in (1) and the FeS x precursor solution are mixed under at least one mechanical external force among high-speed shear emulsification, mechanical stirring, magnetic stirring, and manual stirring to form a uniform mixed sol; the mass ratio of silicate to FeS in the mixed sol x is 0.1 to 10, preferably 0.5 to 2.

[0011] (4) The mixed sol obtained in (3) can be crystallized at 120 to 220 °C for 3 to 72 hours, preferably at 180 to 200 °C for 3 to 72 hours. The crystallization method can adopt common crystallization methods such as heating crystallization in an oven, electric furnace, etc. in a closed system, microwave heating crystallization, and oil bath heating crystallization in an open system; the separation of the product in the formed gel can adopt product separation methods such as sedimentation separation with a polar solvent, vacuum filtration separation, and centrifugal separation. The product is washed with deionized water and ethanol and directly dispersed into one or more hydrogen-donating solvents such as phenol, tetralin, and decalin, and thus the FeS x / layered silicate nanocomposite catalyst slurry is obtained.

[0012] The FeS obtained by the above preparation method of the present invention x / The layered silicate nanocomposite catalyst can be used for the hydrocracking reaction of asphaltene liquid phase obtained by extracting C5-C8 normal paraffins from heavy oil with an API of 1 to 20 to produce light oil products. The reaction conditions are as follows: the mass percentage of the catalyst / asphaltene is 0.1% to 10.0%, preferably 1.0% to 4.0%; the reaction temperature is 380 to 500 °C, preferably 430 to 450 °C; the reaction time is 4 h; the reaction pressure is 10 to 25 MPa, preferably 13 to 18 MPa.

[0013] The FeS prepared in the present invention x / Characterization results of the layered silicate nanocomposite catalyst: The FeS prepared in the present invention x / The size of the layered silicate nanocomposite catalyst is about 30 nm (see Figure 1 ), and it is a highly dispersed granular form. The particle size of FeS on the layered silicate disk x is 1 to 5 nm, and the spherical FeS x nanoparticles have no agglomeration (see Figure 2 ). This result is completely different from that of the comparative sample of pure FeS x catalyst, whose particle size ranges from several hundred nanometers to micron size and shows obvious agglomeration.

[0014] The present invention has the following advantages and effects compared with the prior art:

[0015] (1) In the present invention, by compounding iron sulfide with nanoscale layered silicate, an FeS x / layered silicate nanocomposite catalyst is prepared. The asphaltene structure consists of three levels, namely polycyclic aromatic "flakes", "crystal-like aggregates" and "micelles". Among them, the diameter of the polycyclic aromatic unit flakes of asphaltene is about 1 nm, and the relative molecular mass is 600 to 1000; the diameter of the crystal-like aggregates is 2 to 2 nm; while the diameter of the general asphaltene "micelles" is about 10 to 30 nm. The microstructure of the nanoscale layered silicate is a disk with a sheet diameter not greater than 35 nm, which is stacked parallel to each other in the solid state. After being compounded with FeS x nanoparticles, it is directly dispersed in the hydrogen donor, and the disks can no longer be stacked parallel and exist in the form of single disks. Therefore, an FeS x / layered silicate nanocomposite catalyst with a size of about 30 nm is formed.

[0016] (2) Since the particle size of pure FeS x is much larger than that of the FeS x / layered silicate nanocomposite catalyst prepared in the present invention, its suspension property is poor in the liquid-phase hydrocracking and lightening reaction of asphaltene. FeS xAfter separation, the FeS / layered silicate nanocomposite catalyst can be directly dispersed in the hydrogen-donating solvent without drying, which avoids the stacking of layered silicates into large particles in the solid state and maintains its nanoscale size. Therefore, in the asphaltene liquid-phase hydrocracking reaction system, this nanoscale composite catalyst can be highly dispersed and suspended in the reaction system to fully contact with the micelles of asphaltenes and quickly undergo hydrocracking reactions, avoiding catalyst deactivation caused by asphaltene coking and achieving the non-coking full conversion of asphaltenes into light oils.

[0017] (3) The FeS x / layered silicate nanocomposite catalyst prepared in the present invention is inexpensive and highly economical. The one-step low-temperature synthesis method is simple to operate and convenient for industrial scale-up production. When used in the asphaltene liquid-phase hydrocracking reaction, it can be directly used without pre-sulfidation and pre-mixing treatments. When used in the asphaltene liquid-phase hydrocracking reaction, it has high reaction activity. The reaction results are shown in Table 1. The FeS x / layered silicate nanocomposite catalyst has a light oil yield as high as 48.0% in the products of the asphaltene liquid-phase hydrocracking reaction and no coking. While for the comparative sample FeS x catalyst, the light oil yield in the products of the asphaltene liquid-phase hydrocracking reaction is only 8.9%, and the coking rate is 7.8%.

[0018] The FeS x / layered silicate nanocomposite catalyst obtained in the present invention can be used in the reaction of asphaltene liquid-phase hydrocracking to produce light oils. The present invention solves the problems of poor contact with the catalyst and low catalyst activity during the asphaltene liquid-phase hydrocracking process, resulting in coking and low economy, realizes the full hydrogenation conversion of asphaltenes and the recycling of the catalyst, and improves the economy of the slurry-phase hydrocracking catalyst. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 SEM photographs of the pure FeS obtained in Comparative Example 1 x and the FeS x / layered silicate nanocomposite catalyst obtained in Example 2.

[0020] Figure 2 The pure FeS obtained in Comparative Example 1 x and the FeS x / layered silicate nanocomposite catalyst obtained in Example 2. DETAILED DESCRIPTION OF THE INVENTION

[0021] In order to further illustrate the present invention, the following examples are listed, but they do not limit the scope of the present invention.

[0022] Example 1:

[0023] Weigh 1.0 g of lithium magnesium silicate nanosheets (lithium magnesium silicate synthesized by hydrothermal method, with an average particle size of 80 nm measured by a nano laser particle size analyzer, a single-layer disc size of 20 nm, and a thickness of 1.0 nm for a single disc) and disperse it in 60 m of deionized water. Shear emulsify it for 10 minutes at 13,000 r.m.p. to form a colorless and transparent sol. Dissolve 0.2016 g of ferric nitrate nonahydrate and 0.1562 g of thioacetamide in water to form an FeS x precursor solution. Mix the lithium magnesium silicate sol and the FeS x precursor solution by high-speed shear emulsification for 10 minutes to form a homogeneous mixed sol. Transfer the obtained sol into a stainless-steel hydrothermal autoclave with a polytetrafluoroethylene liner and crystallize it at 180 °C in an electric furnace for 24 hours. After cooling to room temperature, perform suction filtration separation and wash it 3 times with deionized water to obtain a black solid, which is directly dispersed in 30 ml of phenol to obtain an FeS x / lithium magnesium silicate composite catalyst slurry. The test results of the nano laser particle size analyzer show that the average particle size of the FeS / lithium magnesium silicate composite catalyst obtained in this example is 30 nm. Therefore, FeS / lithium magnesium silicate is a nano composite catalyst. SEM characterization shows that the FeS / lithium magnesium silicate nano composite catalyst obtained in this example is a loose nano particle with a particle size of 20 - 36 nm; the HRTEM characterization results show that spherical FeS nano particles are combined with single-layered lithium magnesium silicate discs, and the diameter of the spherical FeS nano particles is 1 - 3 nm, and there is no agglomeration and they are dispersed and combined on a single-layered silicate disc; the diameter of the single-layered lithium magnesium silicate disc is 20 nm.

[0024] The FeS / lithium magnesium silicate nano composite catalyst prepared in this example is used for the hydrocracking reaction of the liquid-phase hydrogenation of asphaltene obtained by extracting C5 - C8 normal paraffins from heavy oil with an API of 1 - 20 (the definition of asphaltene is carried out in accordance with the standard NB / SH / T0509 - 2010). The reaction conditions are as follows: the mass percentage of the catalyst / asphaltene is 2.5%; the reaction temperature is 430 °C; the reaction time is 4 h; the hydrogen reaction pressure is 14 MPa. The liquid-phase autoclave reaction activity results are shown in Table 1. The yield of light oil products with a boiling point of 20 - 350 °C in the liquid-phase hydrogenation cracking products of asphaltene of the FeS / lithium magnesium silicate nano composite catalyst of the present invention is much higher than that of the catalyst of the comparative example, and there is no asphaltene coking phenomenon.

[0025] Example 2:

[0026] Weigh 1.0 g of lithium magnesium silicate (lithium magnesium silicate synthesized by hydrothermal method, with an average particle size of 80 nm measured by a nano laser particle size analyzer, a single-layer disc size of 20 nm, and a disc thickness of 1.0 nm) and disperse it in 60 m of deionized water. Mechanically stir it for 30 minutes to form a colorless and transparent sol. Dissolve 2.2525 g of ferric chloride hexahydrate and 1.008 g of L-cysteine in water to form an FeSx Precursor solution. Lithium magnesium silicate sol and FeS x The precursor solution was mechanically stirred for 1 hour to form a uniform mixed sol. The obtained sol was transferred to a microwave synthesizer with a polytetrafluoroethylene liner and crystallized at 160°C for 6 hours. After cooling to room temperature, it was separated by suction filtration and washed with deionized water 3 times to obtain a black solid, which was directly dispersed in 30 ml of tetralin to obtain FeS x / lithium magnesium silicate nanocomposite catalyst slurry.

[0027] The test results of the nano-laser particle size analyzer show that the FeS x The average particle size of the FeS / LiMgSiO composite catalyst is 33 nm. x / lithium magnesium silicate is a nanocomposite catalyst. SEM characterization shows that the FeS x / Lithium magnesium silicate nanocomposite catalyst is loose nanoparticles with a particle size of 25-35nm; HRTEM characterization results show that FeS x Spherical nanoparticles are composited with a single layered lithium magnesium silicate disk, the spherical FeS x The diameter of the nanoparticles is 2-4nm, and there is no agglomeration; the diameter of the single layered magnesium lithium silicate disk is 20nm.

[0028] The FeS / lithium magnesium silicate nanocomposite catalyst prepared in this embodiment is used for the extraction of C5-C8 normal alkanes from heavy oil with an API of 1 to 20 (the definition of asphaltene is implemented in accordance with the standard NB / SH / T0509-2010) to obtain asphaltene liquid phase hydrocracking to produce light oil products. The liquid phase kettle reaction conditions are: the mass percentage of catalyst / asphaltene is 2.5%; the reaction temperature is 450°C; the reaction time is 4h; the hydrogen reaction pressure is 12MPa. The reaction activity results are shown in Table 1. The yield of light oil products with a boiling point of 20 to 350°C in the asphaltene liquid phase hydrocracking product of the FeS / lithium magnesium silicate nanocomposite catalyst of the present invention is much higher than that of the comparative catalyst, and no asphaltene coking phenomenon occurs.

[0029] Embodiment 3:

[0030] Weigh 1.0g of Laponite (Bick Additives, Inc., USA, artificially synthesized sodium magnesium silicate lithium salt, average particle size 60nm, single layer disc size 25nm, disc thickness 0.92nm) and disperse it in 60ml of deionized water. Stir magnetically for 1 hour to form a colorless transparent sol. Dissolve 1.6666g of ferric sulfate and 3.8416g of glutathione in water to form FeS x Precursor solution. Laponite sol and FeS xThe precursor solution was magnetically stirred for 1 hour to form a homogeneous mixed sol. The obtained sol was transferred into a stainless-steel hydrothermal autoclave with a polytetrafluoroethylene liner and crystallized at 200 °C in an oven for 12 hours. After cooling to room temperature, suction filtration was carried out for separation, and it was washed 3 times with deionized water to obtain a black solid, which was directly dispersed into 30 ml of decahydronaphthalene to obtain FeS x / Laponite nanocomposite catalyst slurry.

[0031] The test results of a nano laser particle size analyzer showed that the average particle size of the FeS2 / Laponite composite catalyst obtained in this example was 25 nm. Therefore, FeS2 / Laponite was a nanocomposite catalyst. SEM characterization showed that the FeS2 / Laponite nanocomposite catalyst obtained in this example was a loose nanoparticle, and the particle size was in the range of 20 - 30 nm; the HRTEM characterization results showed that FeS x spherical nanoparticles were composite with single-layered Laponite disks. The diameter of the spherical FeS2 nanoparticles was 1 - 3 nm, without agglomeration; the diameter of the single-layered Laponite disks was 25 nm.

[0032] The FeS2 / Laponite nanocomposite catalyst prepared in this example was used for the hydrocracking reaction of the liquid-phase hydrogenation of the asphaltene obtained by extracting C5 - C8 normal paraffins from heavy oil with an API of 1 - 20 (the definition of asphaltene was carried out according to the standard NB / SH / T0509 - 2010). The liquid-phase autoclave reaction conditions were as follows: the mass percentage of the catalyst / asphaltene was 2.5%; the reaction temperature was 480 °C; the reaction time was 4 h; the hydrogen reaction pressure was 10 MPa. The reaction activity results are shown in Table 1. The yield of light oil products with a boiling point of 20 - 350 °C in the liquid-phase hydrogenation cracking product of the asphaltene of the FeS2 / Laponite nanocomposite catalyst of the present invention was much higher than that of the catalyst of the comparative example, and there was no asphaltene coking phenomenon.

[0033] Example 4:

[0034] Weigh 0.1 g of Laponite (synthetic lithium magnesium sodium silicate from BYK Additives & Instruments GmbH, with an average particle size of 60 nm, a single-layer disk size of 25 nm, and a disk thickness of 0.92 nm) and disperse it in 60 m of deionized water, and magnetically stir for 1 hour to form a colorless and transparent sol. Dissolve 2.0016 g of ferric nitrate nonahydrate and 1.875 g of thiourea in water to form FeS x precursor solution. Mix the Laponite sol with FeS xThe precursor solution was magnetically stirred for 1 hour for mixing to form a uniform mixed sol. The obtained sol was transferred into a three-necked flask and refluxed and heated in an oil bath at 140 °C for crystallization for 48 hours. After cooling to room temperature, suction filtration separation was carried out, and it was washed 3 times with deionized water to obtain a black solid, which was directly dispersed into 30 ml of decahydronaphthalene to obtain FeS x / Laponite nanocomposite catalyst slurry.

[0035] The test results of the nano laser particle size analyzer show that the average particle size of the FeS x / Laponite composite catalyst obtained in this example is 40 nm. Therefore, FeS x / Laponite is a nanocomposite catalyst. SEM characterization shows that the FeS x / Laponite nanocomposite catalyst obtained in this example is a loose nanoparticle, and the particle size is 38 - 40 nm; the HRTEM characterization results show that FeS x spherical nanoparticles are combined with single-layered Laponite disks, and the diameter of the spherical FeS x nanoparticles is 4 - 5 nm and there is no agglomeration; the diameter of the single-layered Laponite disk is 25 nm.

[0036] The FeS2 / Laponite nanocomposite catalyst prepared in this example was used for the hydrocracking reaction of the liquid-phase addition of asphaltene obtained by extracting C5 - C8 normal paraffins from heavy oil with an API of 1 - 20 (the definition of asphaltene was carried out in accordance with the standard NB / SH / T0509 - 2010). The liquid-phase autoclave reaction conditions were: the mass percentage of the catalyst / asphaltene was 2.5%; the reaction temperature was 380 °C; the reaction time was 4 h; the hydrogen reaction pressure was 22 MPa. The reaction activity results are shown in Table 1. The yield of light oil products with a boiling point of 20 - 350 °C in the hydrocracking product of asphaltene of the FeS2 / Laponite nanocomposite catalyst of the present invention is much higher than that of the comparative catalyst, and there is no coking.

[0037] Example 5:

[0038] 0.5 g of Laponite (synthetic lithium magnesium sodium silicate from BYK Additives & Instruments GmbH, average particle size 60 nm, single-layer disk size 25 nm, disk thickness 0.92 nm) was weighed and dispersed in 60 m of deionized water, and shear emulsification was carried out for 10 minutes to form a colorless and transparent sol. 3.1319 g of iron oxalate and 2.0160 g of L-cysteine were dissolved in water to form a FeS x precursor solution. The Laponite sol and FeS xThe precursor solution was magnetically stirred for 1 hour to form a homogeneous mixed sol. The obtained sol was transferred into a three-necked flask and refluxed and heated in an oil bath at 120 °C for crystallization for 72 hours. After cooling to room temperature, suction filtration was carried out for separation, and it was washed 3 times with deionized water to obtain a black solid, which was directly dispersed in 30 ml of tetralin to obtain FeS x / Laponite nanocomposite catalyst slurry.

[0039] The test results of the nano laser particle size analyzer showed that the average particle size of the FeS x / Laponite composite catalyst obtained in this example was 38 nm. Therefore, FeS x / Laponite was a nano composite catalyst. SEM characterization showed that the FeS x / Laponite nanocomposite catalyst obtained in this example was a loose nano particle, and the particle size was 35 - 40 nm; the HRTEM characterization results showed that FeS x spherical nano particles were combined with single-layered Laponite disks, and the diameter of the spherical FeS x nano particles was 2 - 4 nm without agglomeration; the diameter of the single-layered Laponite disk was 25 nm.

[0040] The FeS2 / Laponite nanocomposite catalyst prepared in this example was used for the hydrocracking reaction of the liquid-phase of the asphaltene obtained by extracting C5 - C8 normal paraffins from heavy oil with an API of 1 - 20 (the definition of asphaltene was carried out in accordance with the standard NB / SH / T0509 - 2010). The liquid-phase autoclave reaction conditions were: the mass percentage of the catalyst / asphaltene was 2.5%; the reaction temperature was 400 °C; the reaction time was 4 h; the hydrogen reaction pressure was 18 MPa. The reaction activity results are shown in Table 1. The yield of light oil products with a boiling point of 20 - 350 °C in the hydrocracking product of the asphaltene of the FeS2 / Laponite nanocomposite catalyst of the present invention was much higher than that of the comparative catalyst, and only 0.1% of coking occurred.

[0041] Example 6:

[0042] 0.5 g of lithium magnesium silicate (lithium magnesium silicate synthesized by hydrothermal method, the average particle size measured by a nano laser particle size analyzer was 80 nm, the single-layer disk size was 20 nm, and the disk thickness was 1.0 nm) was weighed and dispersed in 60 m of deionized water, and shear emulsification was carried out for 10 minutes to form a colorless and transparent sol. 1.6568 g of ferrous chloride tetrahydrate and 1.9500 g of sodium sulfide were dissolved in water to form a FeS x precursor solution. The lithium magnesium silicate sol and FeS xThe precursor solution was magnetically stirred for 1 hour to form a homogeneous mixed sol. The obtained sol was transferred into a polytetrafluoroethylene inner lining and placed in a stainless-steel hydrothermal autoclave electric furnace for crystallization at 220 °C for 3 hours. After cooling to room temperature, suction filtration separation was carried out, and it was washed 3 times with deionized water to obtain a black solid, which was directly dispersed into 30 ml of phenol to obtain FeS x / layered silicate nanocomposite catalyst slurry.

[0043] The test result of the nano laser particle size analyzer shows that the average particle size of the FeS x / lithium magnesium silicate composite catalyst obtained in this example is 40 nm. Therefore, FeS x / lithium magnesium silicate is a nano composite catalyst. SEM characterization shows that the FeS x / lithium magnesium silicate nano composite catalyst obtained in this example is a loose nano particle, and the particle size is between 35 - 40 nm; the HRTEM characterization result shows that FeS x spherical nano particles are composite with single lithium magnesium silicate disks, and the diameter of the spherical FeS x nano particles is 3 - 5 nm, without agglomeration; the diameter of the single layered lithium magnesium silicate disk is 20 nm.

[0044] The FeS / layered silicate nano composite catalyst prepared in this example was used for the hydrocracking reaction of the liquid-phase hydrogenation of the asphaltene obtained from the extraction of C5 - C8 normal paraffins in heavy oil with an API of 1 - 20 (the definition of asphaltene was carried out according to the standard NB / SH / T0509 - 2010). The liquid-phase autoclave reaction conditions were: the mass percentage of the catalyst / asphaltene was 2.5%; the reaction temperature was 420 °C; the reaction time was 4 h; the hydrogen reaction pressure was 16 MPa. The reaction activity results are shown in Table 1. The yield of light oil products with a boiling point of 20 - 350 °C in the liquid-phase hydrogenation cracking products of the asphaltene of the FeS / lithium magnesium silicate nano composite catalyst of the present invention is much higher than that of the comparative catalyst, and there is no asphaltene coking phenomenon. Comparative Example 1:

[0045] 0.2016 g of ferric nitrate nonahydrate and 0.1562 g of thioacetamide were dissolved in water to form a FeS x precursor solution. The obtained sol was transferred into a stainless-steel hydrothermal autoclave with a polytetrafluoroethylene inner lining and crystallized at 180 °C in an electric furnace for 24 hours. After cooling to room temperature, suction filtration separation was carried out, and it was washed 3 times with deionized water to obtain a black solid, which was directly dispersed into phenol to obtain FeS x / layered silicate nano composite catalyst slurry.

[0046] The pure FeS x catalyst obtained in this comparative example, the test result of the nano laser particle size shows that its average particle size is 840 nm. The SEM result shows that the pure FeS xThe particle size of the catalyst ranges from several hundred nanometers to micrometers, and obvious agglomeration is presented. The TEM characterization results show that pure FeS x The catalyst is a solid particle with a rough surface. The particle size is much larger than 100 nm, and the agglomeration is serious.

[0047] Comparative Example 2:

[0048] Weigh 1.0 g of nano - lithium magnesium silicate (lithium magnesium silicate synthesized by hydrothermal method, with an average particle size of 80 nm measured by a nano - laser particle size analyzer, a single - layer disc size of 20 nm, and a disc thickness of 1.0 nm), disperse it in 60 m of deionized water, and shear - emulsify it for 10 minutes at 13000 r.m.p. to form a colorless and transparent sol. Weigh 2.7371 g of cobalt acetate and 3.9890 g of L - cysteine, dissolve them in 60 ml of water under stirring to form a CoS precursor solution. Under the condition of shear - emulsification, uniformly mix the above - mentioned lithium magnesium silicate sol and CoS precursor solution for 10 minutes to obtain a sol. Transfer the obtained sol into a polytetrafluoro - lined container and put it into a microwave synthesizer, and crystallize it at 180 °C for 12 hours. After cooling to room temperature, carry out sedimentation and then suction filtration, wash it 3 times with deionized water and 3 times with ethanol to obtain a black solid, and naturally dry it for 24 hours to obtain a CoS / lithium magnesium silicate nano - composite catalyst.

[0049] The test results of the nano - laser particle size analyzer show that the average particle size of the CoS / lithium magnesium silicate composite catalyst obtained in this example is 180 nm. The SEM characterization shows that the CoS / lithium magnesium silicate nano - composite catalyst obtained in this example is a loose flower - shaped nano - particle, and the particle size is in the range of 150 - 200 nm; the HRTEM characterization and mapping elemental analysis results show that the CoS / lithium magnesium silicate composite catalyst is a core - shell - structured catalyst with a layered silicate single - layer disc as the core and CoS nano - sheets loosely wrapped as the shell.

[0050] Comparative Example 3:

[0051] Weigh 1.0 g of lithium magnesium silicate (lithium magnesium silicate synthesized by hydrothermal method, with an average particle size of 80 nm measured by a nano - laser particle size analyzer, a single - layer disc size of 20 nm, and a disc thickness of 1.0 nm), disperse it in 60 m of deionized water, and shear - emulsify it for 10 minutes at 13000 r.m.p. to form a colorless and transparent sol. Weigh 3.0869 g of nickel sulfate and 3.9890 g of L - cysteine, dissolve them in 60 ml of water under stirring to form a CoS precursor solution. Under the condition of shear - emulsification, uniformly mix the above - mentioned lithium magnesium silicate sol and CoS precursor solution for 10 minutes to obtain a sol. Transfer the obtained sol into a round - bottom flask with a reflux device, and crystallize it in an oil bath at 120 °C for 60 hours. After cooling to room temperature, carry out sedimentation and then suction filtration, wash it 3 times with deionized water to obtain a black solid, and freeze - dry it for 6 hours to obtain a NiS / lithium magnesium silicate nano - composite catalyst.

[0052] The test results of the nano laser particle size analyzer show that the average particle size of the NiS / magnesium silicate lithium composite catalyst obtained in this example is 80 nm. SEM characterization shows that the NiS / magnesium silicate lithium nano composite catalyst obtained in this example is a loose flower-like nano particle with a particle size of 60 - 100 nm; the results of HRTEM characterization and mapping elemental analysis show that the NiS / magnesium silicate lithium composite catalyst is a core-shell structured catalyst with a layered silicate single-layer disc as the core and NiS nano sheets loosely wrapped as the shell.

[0053] The catalysts prepared in Comparative Examples 1 - 3 were used for the reaction of hydrocracking of the asphaltene liquid phase obtained by extracting C5 - C8 normal paraffins from heavy oil with an API of 1 - 20 (the definition of asphaltene was carried out in accordance with the standard NB / SH / T0509 - 2010) to produce light oil products with a boiling point of 20 - 350 °C. The liquid-phase autoclave reaction conditions were: the mass percentage of the catalyst / asphaltene was 2.5%; the reaction temperature was 430 °C; the reaction time was 4 h; the hydrogen reaction pressure was 14 MPa.

[0054] Table 1 FeS prepared by the present invention x / layered silicate nano composite catalyst and the control sample pure FeS x The hydrocracking reaction activity of the asphaltene of the catalyst.

[0055]

Claims

1. A FeS x / layered silicate nanocomposite catalyst, characterized in that: FeS x The composition of the layered silicate nanocomposite catalyst includes FeS x particles and individual layered silicate discs, where x is 1 to 2, and structurally spherical FeS x nanoparticles are attached or dispersed and compounded on the individual layered silicate discs; The spherical FeS described above x The diameter of the nanoparticles is 1 to 5 nm; FeS x The preparation of the layered silicate nano-composite catalyst comprises the following steps: (1) Disperse the layered silicate in water to form a colorless and transparent sol under the action of mechanical external force; (2) Dissolve one or a mixture of two or more of iron nitrate, iron chloride, iron sulfate, iron chloride, iron oxalate, iron acetate, and iron citrate in water as the iron source and sulfur source to form an FeS x precursor solution; (3) Mix the sol obtained in step (1) with the FeS x precursor solution under mechanical external force to form a homogeneous mixed sol; (4) Heat-treat and crystallize the mixed sol obtained in step (3), then cool it, and separate the product in the formed gel to obtain FeS. x / layered silicate nanocomposite catalyst slurry; The layered silicate used is one or more of chemically synthesized magnesium silicate, lithium magnesium silicate, and sodium lithium magnesium silicate with a particle size of 10 - 100 nm; The sulfur source used is one or a mixture of two or more of soluble sodium sulfide, potassium sulfide, ammonium sulfide, thiourea, thioacetamide, cysteine, and glutathione; In step (3), the mass ratio of layered silicate to FeS in the mixed sol x is 0.1 to 10.

2. The FeS x / layered silicate nanocomposite catalyst according to claim 1, characterized in that: The described FeS x The particle size of the layered silicate nano-composite catalyst is 20 - 40 nm; Mass ratio of layered silicate and spherical FeS nanoparticles in the composite catalyst x is 0.1 to 10; The spherical FeS x nanoparticles are non-aggregated and dispersed in a composite manner on a single-layered silicate disk; The diameter of a single layered silicate disc is 1 - 35 nm, and the thickness of a single disc is 0.7 - 2.2 nm.

3. The FeS x / layered silicate nanocomposite catalyst according to claim 1, characterized in that: The mass ratio of the layered silicate to the spherical FeS nanoparticles in the composite catalyst x is 0.5 to 2.

0.

4. The FeS x / layered silicate nanocomposite catalyst according to claim 1, characterized in that: Mass ratio of layered silicate and spherical FeS nanoparticles in composite catalyst x is 0.9~1.

2.

5. The FeS x / layered silicate nanocomposite catalyst according to claim 1, characterized in that: In step (3), the mass ratio of the layered silicate to FeS in the mixed sol x is 0.5 to 2.

6. The FeS x / layered silicate nanocomposite catalyst, characterized in that: In step (3), the mass concentration range of the layered silicate in the mixed sol is 0.8 - 45 mg / ml; in step (4), the crystallization temperature of the mixed sol is 120 - 220 °C for 3 - 72 hours, Separate the product in the formed gel and directly disperse it into the hydrogen - donating solvent. The hydrogen - donating solvent used is one or a mixture of two or more of phenol, tetralin, and decalin.

7. The FeS x / layered silicate nanocomposite catalyst, characterized in that: In step (4), the crystallization temperature of the mixed sol is 180 - 200 °C for 3 - 72 hours.

8. The FeS x / layered silicate nanocomposite catalyst according to claim 1, characterized in that: The mechanical external force used to form the sol is one or more of high - speed shear emulsification, mechanical stirring, magnetic stirring, manual stirring, and ultrasound.

9. The FeS as described in any one of claims 1-8 x / layered silicate nanocomposite catalyst is used in the liquid-phase hydrocracking reaction of asphaltene obtained by extracting C5-C8 n-alkanes from heavy oil with an API of 1 to 20 to produce light oil products.

10. Use of the FeS x / layered silicate nanocomposite catalyst according to claim 9, characterized in that: FeS x / The layered silicate nanocomposite catalyst is used for the liquid-phase hydrocracking reaction of asphaltene, and the reaction conditions are as follows: the mass percentage of the catalyst / asphaltene is 0.1% to 10.0%, the reaction temperature is 380 to 500 °C, and the hydrogen pressure is 10 to 25 MPa.

11. Use of the FeS x / layered silicate nanocomposite catalyst according to claim 10, characterized in that: The mass percentage content of the catalyst / asphaltene is 1.0% - 4.0%; the reaction temperature is 430 - 450 °C; the hydrogen pressure is 13 - 18 MPa.

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