Zirconium-doped titanyl sulfate composite bimetallic base catalyst, and preparation method and application thereof

Abstract

The present application relates to the technical fields of fossil energy, biomass, mining and the like, and particularly relates to a zirconium-doped titanyl sulfate composite bimetallic catalyst, a preparation method and application thereof. n (TiOSO4) m , n and m are both selected from positive numbers. The above-mentioned bimetallic catalyst is used for catalytic pyrolysis of fossil energy / biomass, especially oil shale, which can effectively reduce the activation energy of the pyrolysis reaction, and can also increase the content of hydrocarbons in the pyrolysis products, reduce the content of heteroatoms, and increase the content of high-value-added chemicals.

Description

Technical Field

[0001] This invention relates to the fields of fossil energy, biomass, and mining, specifically to a zirconium-doped titanium oxysulfate composite bimetallic catalyst, its preparation method and application, and a method for processing fossil energy / biomass. Background Technology

[0002] With rapid industrialization and urbanization, the global energy crisis triggered by the rapid depletion of limited conventional fossil fuels such as coal, oil, and natural gas has become a major bottleneck hindering sustainable social development. Besides vigorously developing various renewable and sustainable energy sources such as hydropower, electricity, solar energy, wind energy, geothermal energy, and biomass energy, the development of unconventional fossil fuels such as oil shale, shale oil, heavy oil, and oil sands has also attracted widespread attention in the scientific and technological fields, and is considered one of the important strategic resources that have the potential to replace / supplement traditional conventional fossil fuels. As an important unconventional fossil fuel, oil shale is a high-ash solid combustible sedimentary rock formed from complex organic matter and inorganic minerals. Through a thermal treatment process in an anaerobic environment, its organic matter can be converted into shale oil, which can be used as an alternative energy source. Therefore, the thermochemical treatment of oil shale has attracted widespread attention in many scientific and industrial fields. Among them, how to achieve its effective extraction is one of the research hotspots.

[0003] Among various methods to improve the efficiency of oil shale extraction, catalyst-assisted catalytic pyrolysis of oil shale is one of the important approaches. On the one hand, the introduction of catalysts can reduce the activation energy of the pyrolysis reaction to a certain extent, thus providing scientific and practical space for reducing energy consumption. On the other hand, the selectivity of bimetallic catalysts can also increase the hydrocarbon content and reduce the heteroatom content in the pyrolysis products, thereby increasing the content of high-value-added chemicals. Therefore, developing novel catalysts aimed at improving the efficiency of oil shale extraction is a topic of significant scientific and practical importance.

[0004] To date, catalytic systems based on primary minerals in oil shale and externally introduced catalysts, such as various minerals, inorganic or organometallic salts, metal oxides / sulfides, transition metal carbonyl compounds, porous materials, and organic polymers, have certain limitations. The proposed catalysts suffer from problems such as requiring cumbersome pretreatment on oil shale, complex catalyst preparation processes, high catalyst production costs, easy deactivation due to pore blockage, time-consuming impregnation and / or subsequent drying processes, and unsatisfactory selectivity.

[0005] Therefore, considering the strategic significance of oil shale, developing new catalytic materials for the efficient pyrolysis of oil shale remains an important topic for further exploration. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems of complex use, high production cost, and poor catalytic effect of catalysts used in the pyrolysis of fossil energy / biomass in the prior art, and to provide a zirconium-doped titanium oxysulfate composite bimetallic catalyst, its preparation method and application, and a method for processing fossil energy / biomass.

[0007] The active components of the bimetallic catalyst researched by the inventors are selected from zirconium and titanium. The bimetallic catalyst is used for the catalytic pyrolysis of fossil energy / biomass, especially oil shale. Compared with the prior art, the introduction of the bimetallic catalyst can more effectively reduce the activation energy of the pyrolysis reaction. Furthermore, through the selectivity of the bimetallic catalyst, the hydrocarbon content in the pyrolysis products can be further increased, the heteroatom content can be reduced, and the content of high value-added chemicals can be increased.

[0008] To achieve the above objectives, a first aspect of the present invention provides a zirconium-doped titanium oxysulfate composite bimetallic catalyst, wherein the active component of the bimetallic catalyst is selected from zirconium and titanium; the general formula of the bimetallic catalyst is Zr. n (TiOSO4) m Both n and m are selected from positive numbers.

[0009] In this invention, unless otherwise specified, the zirconium-doped titanium oxysulfate composite bimetallic catalyst is simply referred to as a bimetallic catalyst.

[0010] Preferably, in the bimetallic catalyst, the concentration of 0 μmol / g < β-acid ≤ 1 × 10⁻⁶ 6 μmol / g, 0 μmol / g < L-acid concentration ≤ 1 × 10 6 μmol / g.

[0011] A second aspect of this invention provides a method for preparing a zirconium-doped titanium oxysulfate composite bimetallic catalyst. The method includes: dissolving a soluble ammonium salt, a soluble zirconium salt, and titanium oxysulfate in water; adding an alkali to adjust the pH value; and sequentially stirring and drying the dispersion system. The resulting white solid is then calcined to obtain a catalyst with the general formula Zr. n (TiOSO4) m The bimetallic catalyst, where n and m are both selected from positive numbers.

[0012] The third aspect of this invention provides a bimetallic catalyst provided in the first aspect, or a bimetallic catalyst prepared by the preparation method provided in the second aspect, for use in the processing of fossil energy / biomass.

[0013] The fourth aspect of the present invention provides a method for processing fossil energy / biomass, the method comprising: contacting a catalyst with fossil energy / biomass and carrying out a pyrolysis reaction under a non-oxidizing gas, an inert gas or an oxygen-deficient atmosphere to obtain pyrolysis products;

[0014] The catalyst is selected from the bimetallic catalyst provided in the first aspect, or the bimetallic catalyst prepared by the preparation method provided in the second aspect.

[0015] The beneficial technical effects achieved by the present invention through the above technical solution are as follows:

[0016] (1) In the technical solution provided by this invention, zirconium and titanium are selected as active components in the bimetallic catalyst. On the one hand, the introduction of the bimetallic catalyst can significantly reduce the activation energy of the pyrolysis reaction, thereby providing scientific and practical space for reducing energy consumption. On the other hand, the selectivity of the bimetallic catalyst can further increase the hydrocarbon content and reduce the heteroatom content in the pyrolysis products, thereby increasing the content of high-value-added chemicals. These factors endow this type of compound with rich diversity and flexibility, thus providing a rich and diverse material basis for its application as a catalyst for oil shale pyrolysis.

[0017] (2) This invention prepares a zirconium-doped titanium oxysulfate composite bimetallic catalyst using a simple wet chemical-calcination method. Further application of this material to the catalytic pyrolysis of oil shale revealed that, compared to existing technologies, the activation energy of the oil shale pyrolysis reaction can be reduced by 10%, the heteroatom content reduced by 55.4%, the hydrocarbon compound content increased by 34.4%, and the high-value-added toluene content increased by 466.7%. Attached Figure Description

[0018] Figure 1A is a schematic diagram of the preparation of the zirconium-doped titanium oxysulfate composite bimetallic catalyst provided by the present invention; Figures 1B-1C are SEM images of the zirconium-doped titanium oxysulfate composite bimetallic catalyst provided by the present invention; Figure 1D is a TEM image of the zirconium-doped titanium oxysulfate composite bimetallic catalyst provided by the present invention; Figures 1E-1H are elemental mapping analysis diagrams of the nanostructure corresponding to the TEM image shown in Figure 1D.

[0019] Figure 1I is the PXRD diffraction pattern of the zirconium-doped titanium oxysulfate composite bimetallic catalyst provided by the present invention; Figure 1J is an enlarged view of the PXRD diffraction pattern of the zirconium-doped titanium oxysulfate composite bimetallic catalyst provided by the present invention in the diffraction peak range of 2θ = 14-32°; Figure 1K is the FTIR pattern of the zirconium-doped titanium oxysulfate composite bimetallic catalyst provided by the present invention.

[0020] Figure 2A-2D is the XPS spectrum of the zirconium-doped titanium oxysulfate composite bimetallic catalyst provided by this invention; Figure 2 E is the Py-FTIR diagram of the zirconium-doped titanium oxysulfate composite bimetallic catalyst provided by this invention;

[0021] Figure 3 A represents the TG curves of the original oil shale pyrolysis system without zirconium-doped titanium oxysulfate composite bimetallic catalyst at different heating rates. Figure 3 B represents the DTG curves of the original oil shale pyrolysis system without zirconium doping and titanium oxysulfate composite bimetallic catalyst at different heating rates. Figure 3 C represents the TG curves of the oil shale pyrolysis system with zirconium-doped titanium oxysulfate composite bimetallic catalyst at different heating rates. Figure 3 D is the DTG curve of the oil shale pyrolysis system with zirconium-doped titanium oxysulfate composite bimetallic catalyst at different heating rates.

[0022] Figure 4 A and Figure 4 B represents the TG and DTG curves of different oil shale pyrolysis systems at a heating rate of 10 K / min. Figure 4 C and Figure 4 D represents the TG and DTG curves of different oil shale pyrolysis systems at a heating rate of 15 K / min. Figure 4 E and Figure 4 F represents the TG and DTG curves of different oil shale pyrolysis systems at a heating rate of 20 K / min. Figure 4 G and Figure 4 H represents the TG and DTG curves of different oil shale pyrolysis systems at a heating rate of 25 K / min. Figure 4 I and Figure 4 J represents the TG and DTG curves of different oil shale pyrolysis systems at a heating rate of 30 K / min.

[0023] Figure 5 A represents the original oil shale pyrolysis system without zirconium doping, based on the Starink approximation equation. With 1 / T α The relationship curve between the two curves; Figure 5 B is the oil shale pyrolysis system fitted by a zirconium-doped titanium oxysulfate composite bimetallic catalyst based on the Starink approximation equation. With 1 / T α The relationship curve between the two curves; Figure 5 C is based on the Starink method, among different oil shale pyrolysis systems, E α As a function distribution graph of α;

[0024] Figure 5 D is the original oil shale pyrolysis system without this bimetallic catalyst, based on the FWO method fitting of ln(β) and 1 / T. α The relationship curve between the two curves; Figure 5 E is the ln(β) and 1 / T of the oil shale pyrolysis system containing this bimetallic catalyst, fitted using the FWO method. α The relationship curve between the two curves; Figure 5 F is based on the FWO method, which is used to obtain different oil shale pyrolysis systems. α As a function distribution graph of α;

[0025] Figure 5 G is the original oil shale pyrolysis system without this bimetallic catalyst, fitted using the KAS method. With 1 / T α The relationship curve between the two curves; Figure 5 H is the KAS fit of the oil shale pyrolysis system containing this bimetallic catalyst. With 1 / T α The relationship curve between the two curves; Figure 5 I is based on the KAS method, in different oil shale pyrolysis systems, E α As a function distribution graph of α;

[0026] Figure 6 A is the Py-EGA-MS plot of different oil shale pyrolysis systems; Figure 6 B is the MS plot of the products generated in the first peak region of different oil shale pyrolysis systems; Figure 6 C is the MS plot of the products generated in the second peak region for different systems;

[0027] Figure 7 A is the TIC diagram of the products generated by the pyrolysis reaction of different oil shale systems; Figure 7 B is a schematic diagram showing the distribution of hydrocarbons and non-hydrocarbons in different oil shale systems after pyrolysis.

[0028] Figure 8 A-8C is a schematic diagram showing the distribution of components in the products of pyrolysis reactions of different oil shale systems. Detailed Implementation

[0029] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0030] The first aspect of this invention provides a zirconium-doped titanium oxysulfate composite bimetallic catalyst, wherein the active component of the bimetallic catalyst is selected from zirconium and titanium; the general formula of the bimetallic catalyst is Zr. n (TiOSO4) m Both n and m are selected from positive numbers.

[0031] The inventors have discovered that the catalytic pyrolysis of oil shale is a thermochemical transformation process. Lewis acids (i.e., L-acids) and / or Brønsted acids (i.e., β-acids) of the catalyst can serve as active sites, guiding various complex sequential and / or parallel organic transformations through carbocation or free radical mechanisms. However, due to the inherent complexity of oil shale pyrolysis, the underlying mechanisms remain unclear. On the one hand, Zr... 4+ and Ti 4+ The inherent electron-deficient properties of these materials endow them with electron-withdrawing characteristics, thus creating Lewis acid sites. This, in turn, induces the polarization of surface hydroxyl groups and / or strong chemisorption of water molecules, resulting in Brønsted acid sites. On the other hand, the charge imbalance caused by the formation of Ti-O-Zr bonds can also promote the generation of surface acidity. Therefore, it is reasonable to propose that tetravalent zirconium and tetravalent titanium-based composite bimetallic catalysts are suitable catalysts for oil shale pyrolysis.

[0032] In some embodiments of the present invention, preferably, in the bimetallic catalyst, 0 μmol / g < β-acid concentration ≤ 1 × 10⁻⁶ 6 μmol / g, 0 μmol / g < L-acid concentration ≤ 1 × 10 6 μmol / g; more preferably, 0.01 μmol / g ≤ β-acid concentration ≤ 1000 μmol / g, 0.01 μmol / g ≤ L-acid concentration ≤ 500 μmol / g; more preferably, 0.1 μmol / g ≤ β-acid concentration ≤ 500 μmol / g, 0.1 μmol / g ≤ L-acid concentration ≤ 200 μmol / g; most preferably, 1 μmol / g ≤ β-acid concentration ≤ 100 μmol / g, 0.1 μmol / g ≤ L-acid concentration ≤ 50 μmol / g. In this invention, β-acid is... Acids; L-acids are Lewis acids.

[0033] In some embodiments of the present invention, preferably, the bimetallic catalyst has a one-dimensional micro / nano structure.

[0034] In some embodiments of the present invention, preferably, the bimetallic catalyst has a width of 0.01-8000 nm and a length of 0.1-1 × 10⁻⁶ nm. 7nm; more preferably, the width of the bimetallic catalyst is 0.1-500 nm and the length is 1-6000 nm; most preferably, the width of the bimetallic catalyst is 20-200 nm and the length is 100-1000 nm.

[0035] In some embodiments of the present invention, preferably, the molar ratio of zirconium to titanium in the active component is 1:6000-5000:1, for example, 1:4000, 1:2000, 1:500, 1:100, 1:10, 1:1, 10:1, 100:1, 1000:1, 2000:1, 3000:1, 4000:1, 5000:1, and any value within the range of any two of the above values, preferably 1:800-700:1. In the present invention, the molar ratio of zirconium to titanium in the active component is equivalent to n:m in the general formula of bimetallic catalysts.

[0036] In some embodiments of the present invention, the content of the active component, based on the total amount of the bimetallic catalyst, is 0.0001-73 wt%, for example, 0.0001 wt%, 0.005 wt%, 0.01 wt%, 0.05 wt%, 1 wt%, 5 wt%, 10 wt%, 20 wt%, 30 wt%, 32 wt%, 40 wt%, 50 wt%, 60 wt%, 70 wt%, 73 wt%, and any value within the range of any two of the above values, preferably 0.005-32 wt%.

[0037] The zirconium-doped titanium oxysulfate composite bimetallic catalyst provided by this invention can be prepared by a simple wet chemical-calcination method. The preparation process is simple and easy to operate, with low production cost, and it is not easily deactivated during use and has high selectivity.

[0038] In some embodiments of the present invention, the bimetallic catalyst is prepared by a wet chemical-calcination method.

[0039] A second aspect of this invention provides a method for preparing a zirconium-doped titanium oxysulfate composite bimetallic catalyst. The method includes: dissolving a soluble ammonium salt, a soluble zirconium salt, and titanium oxysulfate in water; adding an alkali to adjust the pH value; and sequentially stirring and drying the dispersion system. The resulting white solid is then calcined to obtain a catalyst with the general formula Zr. n (TiOSO4) m A bimetallic catalyst, wherein n and m are both selected from positive numbers.

[0040] The method for preparing the zirconium-doped titanium oxysulfate composite bimetallic catalyst of the present invention is simple and easy to operate, and the required raw materials are readily available and inexpensive, with low requirements for preparation conditions and high preparation efficiency.

[0041] In some embodiments of the present invention, preferably, the soluble ammonium salt is selected from at least one of ammonium chloride, ammonium nitrate, ammonium sulfate and ammonium phosphate, and preferably ammonium sulfate.

[0042] In some embodiments of the present invention, preferably, the soluble zirconium salt is selected from at least one of zirconium chloride, zirconium nitrate, zirconium sulfate, and zirconium phosphate, and more preferably zirconium nitrate. The zirconium salt is an anhydrous salt or a hydrate.

[0043] In one specific embodiment of the present invention, the titanium oxysulfate is TiOSO4·yH2O (y≥0).

[0044] In some embodiments of the present invention, preferably, the content of soluble ammonium salt in the dispersion system is 0.001wt%-55wt%, for example, 0.001wt%, 0.005wt%, 0.05wt%, 0.5wt%, 5wt%, 10wt%, 20wt%, 30wt%, 40wt%, 50wt%, 55wt%, and any value within the range of any two of the above values.

[0045] In some embodiments of the present invention, preferably, the weight ratio of the soluble zirconium salt to titanium oxysulfate in the dispersion system is 1:3000-2000:1, for example, 1:3000, 1:2000, 1:1000, 1:500, 1:100, 1:10, 1:1, 10:1, 50:1, 100:1, 200:1, 300:1, 500:1, 1000:1, 2000:1, and any value within the range of any two of the above values, preferably 1:500-300:1. In the present invention, controlling the weight ratio of the soluble zirconium salt to titanium oxysulfate within the above range allows the prepared bimetallic catalyst to have a reasonable zirconium-to-titanium ratio.

[0046] In some embodiments of the present invention, the pH value of the dispersion system is adjusted to 1-14 using an alkali, for example, 1, 3, 5, 7, 9, 11, 12, 13, 14, and any value within the range of any two of the above values, preferably 3-14. In the present invention, controlling the pH value of the dispersion system within the above range enables the preparation process to proceed smoothly.

[0047] In some embodiments of the present invention, preferably, the alkali is selected from at least one of sodium hydroxide, ammonia, potassium hydroxide and lithium hydroxide, and preferably ammonia.

[0048] In some embodiments of the present invention, the dispersion and mixing temperature is 15-40°C, for example, 15°C, 18°C, 20°C, 25°C, 30°C, 35°C, 40°C, or any value within the range of any two of the above values, preferably 20-25°C; the dispersion and mixing time is 0.01-168h, for example, 0.01h, 0.1h, 0.5h, 5h, 20h, 30h, 50h, 80h, 100h, 120h, 140h, 160h, 168h, or any value within the range of any two of the above values, preferably 0.1-120h. In the present invention, the above dispersion and mixing conditions enable the materials in the dispersion system to be more uniformly dispersed, forming a catalyst with higher selectivity and less susceptibility to deactivation.

[0049] In this invention, the filtration is intended to separate the dispersion system into solid and liquid components.

[0050] In some embodiments of the present invention, preferably, the drying temperature is 50-300℃, for example, 50℃, 70℃, 80℃, 100℃, 130℃, 160℃, 200℃, 240℃, 260℃, 280℃, 300℃, and any value within the range of any two of the above values, preferably 50-200℃; the drying time is 0.01-120h, for example, 0.1h, 0.5h, 5h, 20h, 30h, 50h, 80h, 100h, 120h, and any value within the range of any two of the above values, preferably 0.1-72h. In the present invention, the above drying conditions allow the material to be dried more thoroughly, forming a catalyst with higher selectivity and less susceptibility to deactivation.

[0051] In some embodiments of the present invention, preferably, the calcination temperature is 200-800℃, for example, 200℃, 300℃, 350℃, 400℃, 450℃, 500℃, 600℃, 700℃, 800℃, or any value within the range of any two of the above values, preferably 350-500℃; the calcination time is 0.01-72h, for example, 0.1h, 0.5h, 5h, 20h, 30h, 50h, 60h, 70h, 72h, or any value within the range of any two of the above values, preferably 0.1-24h. These calcination conditions allow for more complete calcination of the material, resulting in a catalyst with higher selectivity and less susceptibility to deactivation.

[0052] In one specific embodiment of the present invention, a certain amount of (NH4)2SO4 is dissolved in water, and an appropriate amount of Zr(NO3)4·xH2O (x≥0) and a certain amount of TiOSO4·yH2O (y≥0) are added to the solution under stirring; the pH value is adjusted to 1-14 using an appropriate amount of NH3·2H2O, and the dispersion system is stirred at 15-40℃ for 0.01-168h. Then, the gel is dried at 50-300℃ until a white solid is obtained; finally, the solid is transferred to a muffle furnace and calcined at 200-800℃ for 0.01-72h.

[0053] The zirconium-doped titanium oxysulfate composite bimetallic catalyst provided by this invention can be prepared by a simple wet chemical-calcination method. The preparation process is simple, highly operable, and has low production costs. It is not easily deactivated during use and exhibits high selectivity. Furthermore, it eliminates the need for cumbersome pretreatment of oil shale or similar materials during application.

[0054] The third aspect of this invention provides the application of a bimetallic catalyst provided in the first aspect, or a bimetallic catalyst prepared by the preparation method provided in the second aspect, in the processing of fossil energy / biomass.

[0055] In some embodiments of the present invention, preferably, the weight ratio of the bimetallic catalyst to fossil energy / biomass is 1:8000-20:1, for example, 1:8000, 1:5000, 1:3000, 1:1000, 1:500, 1:200, 1:100, 1:50, 1:10, 1:5, 1:1, 2:1, 5:1, 10:1, 20:1, and any value within any range of any two values, preferably 1:3000-2:1.

[0056] In some embodiments of the present invention, preferably, the fossil energy source is selected from at least one of oil shale, coal, petroleum, shale oil, heavy oil and oil sands, and preferably oil shale.

[0057] In some embodiments of the present invention, preferably, the biomass is selected from at least one of solid waste, sewage wastewater, agricultural crops, agricultural crop waste, forestry resources, and animal manure.

[0058] In this invention, there is a wide range of options for the processing method. Preferably, the processing method is selected from catalytic pyrolysis.

[0059] In this invention, using a zirconium-doped titanium oxysulfate composite bimetallic catalyst to process fossil fuels, biomass, and other materials, especially oil shale, can effectively reduce the activation energy of the pyrolysis reaction. Furthermore, the selectivity of the bimetallic catalyst can increase the hydrocarbon content and reduce the heteroatom content in the pyrolysis products, thereby increasing the content of high-value-added chemicals.

[0060] In this invention, unless otherwise specified, the activation energy parameter of the pyrolysis reaction is obtained from the relationship curve between the weight loss rate and temperature of substances such as fossil fuels and biomass.

[0061] In this invention, unless otherwise specified, the activation energy change rate parameter is obtained by analyzing the relationship curves between weight loss rate and temperature of the pyrolysis systems containing and without bimetallic catalysts, to obtain their respective pyrolysis activation energies, and by comparing the activation energies of the pyrolysis systems containing and without bimetallic catalysts.

[0062] The fourth aspect of the present invention provides a method for processing fossil energy / biomass, the method comprising: contacting a catalyst with fossil energy / biomass and carrying out a pyrolysis reaction under a non-oxidizing gas, an inert gas or an oxygen-deficient atmosphere to obtain pyrolysis products;

[0063] The catalyst is selected from the bimetallic catalyst provided in the first aspect of the present invention, or the bimetallic catalyst prepared by the preparation method provided in the second aspect.

[0064] Using the zirconium-doped titanium oxysulfate composite bimetallic catalyst provided by this invention for catalytic pyrolysis of fossil energy / biomass can reduce the activation energy of the pyrolysis reaction. Furthermore, the selectivity of the bimetallic catalyst can increase the hydrocarbon content and reduce the heteroatom content in the pyrolysis products, thereby increasing the content of high-value-added chemicals.

[0065] In this invention, unless otherwise specified, the types of bimetallic catalysts and fossil energy / biomass are all as defined above, and will not be elaborated upon here.

[0066] In some embodiments of the present invention, the method includes the following steps:

[0067] (1) The bimetallic catalyst is mixed with fossil energy / biomass under a non-oxidizing gas, inert gas or oxygen-deficient atmosphere to obtain a mixture;

[0068] (2) The mixture is subjected to a pyrolysis reaction in a non-oxidizing gas, an inert gas or an oxygen-deficient atmosphere to obtain pyrolysis products.

[0069] The above-mentioned catalytic pyrolysis method can effectively reduce the activation energy of the pyrolysis reaction. It can also increase the hydrocarbon content and reduce the heteroatom content in the pyrolysis products by selectively using bimetallic catalysts, thereby increasing the content of high-value-added chemicals.

[0070] In this invention, the mixing method in step (1) has a wide range of options, as long as the bimetallic catalyst is mixed evenly with fossil energy / biomass. In some embodiments of this invention, the mixing method is selected from soaking / grinding.

[0071] In some embodiments of the present invention, the mixing time is 0-24h, for example, 0h, 0.5h, 3h, 5h, 10h, 12h, 18h, 20h, 24h, and any value within the range of any two of the above values, preferably 0-3h.

[0072] In some embodiments of the present invention, the bimetallic catalyst is mixed with fossil energy / biomass in the form of a solid powder and then ground to obtain an average particle size of 1×(10⁻⁶). -6 -10 10 A mixture of 1 × (10⁻⁶) μm particles. The bimetallic catalyst has an average particle size of 1 × (10⁻⁶) μm. -4 -10 6 The micrometer size is 0.001-600 μm, preferably 0.001-600 μm.

[0073] In this invention, unless otherwise specified, when the pyrolysis reaction is carried out on Earth, there is a requirement for the average particle size of the bimetallic catalyst, namely, the average particle size of the bimetallic catalyst is 1×(10⁻⁶). -4 -10 6 The average particle size of the bimetallic catalyst is 600-0.001 μm, preferably 600-0.001 μm. When the pyrolysis reaction is carried out underground, there are no special requirements for the average particle size of the bimetallic catalyst. The reason is that when the pyrolysis reaction is carried out underground, the underground rocks are cracked by underground explosion or fracturing. The particle size of the rocks can be hundreds of meters or even larger. This is equivalent to the formation of rocks of various sizes by underground explosion. Then the bimetallic catalyst only adheres to the surface of the rocks in the dominant channels for producing oil / gas underground.

[0074] In some embodiments of the present invention, preferably, the weight ratio of the bimetallic catalyst to fossil energy / biomass is 1:8000-20:1, for example, 1:8000, 1:5000, 1:3000, 1:1000, 1:500, 1:200, 1:100, 1:50, 1:10, 1:5, 1:1, 2:1, 5:1, 10:1, 20:1, and any value within any range of two such values, preferably 1:3000-2:1. Wherein, the weight of the bimetallic catalyst is expressed as Zr... n (TiOSO4) m A weight (where n and m are both positive numbers) is used. In this invention, controlling the above weight ratio within a specific range allows the pyrolysis reaction to proceed more completely.

[0075] In this invention, the conditions for the pyrolysis reaction are subject to a wide range of selection. Preferably, the temperature of the pyrolysis reaction is 0-1000℃, for example, 0℃, 5℃, 10℃, 20℃, 100℃, 200℃, 300℃, 400℃, 500℃, 600℃, 700℃, 800℃, 900℃, 1000℃, and any value within the range of any two of the above values, preferably 80-700℃.

[0076] In some embodiments of the present invention, preferably, the pyrolysis reaction time is 0.0001s-8 years, for example, 0.0001s, 0.001s, 1s, 1min, 1h, 20h, 1 day, 72h, 30 days, 1 year, 2 years, 3 years, 4 years, 5 years, 6 years, 7 years, 8 years, and any value within the range of any two of the above values, preferably 0.001s-72h.

[0077] In some embodiments of the present invention, preferably, the heating rate of the pyrolysis reaction is 0-9000℃ / s, for example, 0℃ / s, 2℃ / s, 10℃ / s, 50℃ / s, 100℃ / s, 500℃ / s, 1000℃ / s, 3000℃ / s, 5000℃ / s, 8000℃ / s, 9000℃ / s, and any value within the range of any two of the above values, preferably 0-6000℃ / s.

[0078] In this invention, by controlling the conditions of the above-mentioned pyrolysis reaction within a specific range, the pyrolysis reaction can be carried out more completely.

[0079] In this invention, unless otherwise specified, the heating rate parameter of the pyrolysis reaction depends on the heating method; when using the Curie point heating method, the heating rate can be as high as 10000℃ / s, while when using other heating methods, the heating rate can be as low as 0.0001℃ / s. Furthermore, when the pyrolysis reaction is carried out at an isothermal temperature, the heating rate is 0℃ / s.

[0080] In this invention, unless otherwise specified, the time parameters of the pyrolysis reaction depend on the specific conditions. When the pyrolysis reaction is carried out underground, the reaction time can be as long as 1-8 years, or even as short as a few days or months.

[0081] In some embodiments of the present invention, the inert gas is selected from at least one of nitrogen, argon, helium, krypton, neon and xenon, preferably nitrogen.

[0082] In some embodiments of the present invention, the non-oxidizing gas is selected from at least one of hydrogen, gaseous water, carbon dioxide, and carbon monoxide.

[0083] In a preferred embodiment of the present invention, the non-oxidizing gas or oxygen-deficient atmosphere may be an underground oxygen-deficient environment.

[0084] In some embodiments of the present invention, the pyrolysis reaction is carried out underground or above ground.

[0085] In one specific embodiment of the present invention, when the pyrolysis reaction is carried out underground, the bimetallic catalyst is directly transported to the underground environment for reaction, or the bimetallic catalyst is transported to the underground environment for reaction by a fluid load.

[0086] In this invention, the fluid can be selected from a wide range of types, including gases and liquids, such as nitrogen, air, helium, CO2, organic solvents, and water.

[0087] In the method provided by this invention, Zr n (TiOSO4) m (Both n and m are positive numbers) As a catalyst, it reacts with fossil energy / biomass (especially oil shale) in a non-oxidizing gas, inert gas or oxygen-deficient atmosphere to obtain pyrolysis products and reduce the activation energy of the pyrolysis reaction. It can also increase the hydrocarbon content and reduce the heteroatom content in the pyrolysis products through the selectivity of bimetallic catalysts, thereby increasing the content of high value-added chemicals.

[0088] Compared with existing technologies, the activation energy of the oil shale pyrolysis reaction can be reduced by 10% after introducing this bimetallic catalyst, the heteroatom content can be reduced by 55.4%, the hydrocarbon compound content can be increased by 34.4%, and the toluene content, which has high added value, can be increased by 466.7%.

[0089] The present invention will be described in detail below through embodiments.

[0090] Example 1

[0091] We prepared zirconium-doped titanium oxysulfate composite bimetallic catalysts via a wet chemical-calcination method, as shown in Figure 1A. The specific method is as follows:

[0092] At room temperature and pressure, 19.8 g of (NH4)2SO4 was dissolved in 90 mL of pure water. Under vigorous magnetic stirring, 1.07 g of Zr(NO3)4·5H2O and 2.36 g of TiOSO4·2H2O were added to the system sequentially, and then 7.5 mL of NH3·H2O was added to adjust the pH to 9. The resulting dispersion was stirred at 25 °C for 24 h to produce a white gel, and then dried at 100 °C until a white solid was obtained. The white solid was transferred to a muffle furnace and calcined at 500 °C for 3 h to obtain a zirconium-doped titanium oxysulfate composite bimetallic catalyst.

[0093] Further analysis, as shown in Figures 1B-1C, revealed by scanning electron microscopy (SEM) characterization of the bimetallic catalysts prepared therefrom, that the bimetallic catalysts are mainly irregular one-dimensional nanostructures with a width of 20-200 nm and a length of 100-1000 nm.

[0094] As shown in Figures 1D-1H, transmission electron microscopy (TEM) and corresponding elemental mapping analysis of the above-mentioned bimetallic catalysts show that Ti, Zr, S and O elements are almost uniformly distributed within this nanostructure.

[0095] As shown in Figures 1I and 1J, powder X-ray diffraction (PXRD) tests were performed on the bimetallic catalyst to further verify the formation of the zirconium-based and titanium-based nanocomposite catalyst. As shown in Figure 1I, the diffraction pattern of the bimetallic catalyst matches well with the diffraction pattern of standard hexagonal titanium oxysulfate. As shown in Figure 1J, the magnified PXRD pattern indicates that, compared with the standard JCPDS file for hexagonal titanium oxysulfate, the main diffraction peaks of this bimetallic catalyst are broadened and shifted to lower angles. This is likely due to the larger radius (0.072 nm) of the tetravalent zirconium ion compared to that of the tetravalent titanium ion (0.061 nm). These results confirm that tetravalent zirconium ions were successfully doped into the titanium oxysulfate lattice, forming a zirconium-doped titanium oxysulfate composite bimetallic nanocomposite catalyst.

[0096] As shown in Figure 1K, the Fourier transform infrared (FTIR) characterization of the above-mentioned bimetallic catalyst reveals numerous surface hydroxyl groups, Zr-O bonds, Ti-O bonds, and Zr-O-Ti bonds, indicating the potential presence of Brønsted (B) and Lewis (L) acid sites within the system. This may endow the catalyst with certain catalytic properties, as many current catalysts function primarily due to their Brønsted (B) and Lewis (L) acid sites.

[0097] In this regard, such as Figure 2 As shown in A-2E, X-ray photoelectron spectroscopy (XPS) and pyridine adsorption Fourier transform infrared spectroscopy (Py-FTIR) were performed on the above bimetallic catalyst. The results showed that Brønsted (B) and Lewis (L) acid centers did indeed exist in the bimetallic catalyst. Both metal ions were in their highest oxidation state, electron-deficient, forming Lewis (L) acid centers, while the surface hydroxyl groups formed their Brønsted (B) acid centers. For example, ... Figure 2As shown in Figure E, at a desorption temperature of 200 °C, the calculated concentrations of Brønsted acid (B-acid) and L-acid sites were 20.7 μmol / g and 6.5 μmol / g, respectively. At a desorption temperature of 350 °C, the concentration of B-acid sites decreased slightly to 17.3 μmol / g, a decrease of 16.4%; while the concentration of L-acid sites decreased significantly to 1.1 μmol / g, a marked decrease of 83.1%. This indicates that the concentration of B-acid sites in this bimetallic catalyst is greater than the concentration of L-acid sites.

[0098] To evaluate the catalytic performance of the zirconium-doped titanium oxysulfate composite bimetallic catalyst for the pyrolysis of oil shale, thermogravimetric (TG) analysis experiments were conducted with and without the aforementioned bimetallic catalyst.

[0099] After introducing the bimetallic catalyst, 10 mg of oil shale with an average particle size ≤74 μm and 1 mg of the bimetallic catalyst sample were placed in a crucible. The heating rates were 10 K / min (10 K / min = 1 / 6 °C / s, the same applies below), 15 K / min, 20 K / min, 25 K / min, and 30 K / min, with a temperature range of 35-980 °C. During the experiment, the flow rate of the carrier gas (dry high-purity nitrogen) was maintained at 50 mL / min (the flow rates of the purge gas and protective gas were both 25 mL / min). For the oil shale pyrolysis system without the introduction of the zirconium-doped titanium oxysulfate composite bimetallic catalyst, except for the experiment with 10 mg of oil shale with an average particle size ≤74 μm, all other conditions were the same as the TG analysis experiment when the bimetallic catalyst was introduced. Each experiment was performed three times under the same conditions to ensure the reliability and repeatability of the results.

[0100] The Starink method is one of the most commonly used accurate model-free isoconversion methods for estimating the apparent activation energy of oil shale pyrolysis. In addition, two other widely used methods, the Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS), were employed to validate the results obtained by the Starink method.

[0101] Based on TG analysis, the above three methods were used to estimate the apparent activation energy of the catalytic and non-catalytic pyrolysis systems of oil shale. A series of TG values ​​obtained at heating rates of 10 K / min, 15 K / min, 20 K / min, 25 K / min, and 30 K / min were analyzed. Figure 3 A and Figure 3 C) and DTG Figure 3 B and Figure 3D) The data were processed and analyzed, and the activation energy changes of the oil shale pyrolysis reaction induced by the bimetallic catalyst were evaluated using three methods. The approximate equations for the Starink method, FWO method, and KAS method are shown in equations (1)-(3), respectively:

[0102]

[0103]

[0104]

[0105] like Figure 4 As shown, a series of TG (triglycerides) were obtained for different pyrolysis systems at different heating rates. Figure 4 A, Figure 4 C Figure 4 E, Figure 4 G and Figure 4 I) and DTG Figure 4 B Figure 4 D、 Figure 4 F, Figure 4 H and Figure 4 We analyzed the data and found that the introduction of this bimetallic catalyst can effectively promote the pyrolysis of organic matter and has good anti-coking performance. We will further study its anti-coking performance below.

[0106] In addition, such as Figure 5 As shown, based on the calculation results of these three methods, the apparent activation energy of the oil shale pyrolysis reaction decreased by an average of 10% after the introduction of this bimetallic catalyst.

[0107] Meanwhile, we also conducted temperature-programmable pyrolysis experiments (Py-EGA-MS) on oil shale pyrolysis systems with and without zirconium-doped titanium oxysulfate composite bimetallic catalysts. When the bimetallic catalyst was introduced, 1 mg of oil shale with an average particle size ≤74 μm and 0.1 mg of the bimetallic catalyst sample were placed in a pyrolysis vessel, with heating rates of 10 K / min and temperatures ranging from 55 to 850 °C. During the experiments, the total flow rate of the carrier gas (dry high-purity helium) was 12.1 mL / min, with column flow rate and purge flow rate of 0.82 mL / min and 3 mL / min, respectively. The m / z range was 10–800, and the column inlet pressure was 80 kPa. To avoid condensation of the pyrolysis products, the GC inlet, column oven, and interface between the GC and MS were all maintained at 300 °C. The ion source was maintained at 250 °C during the experiments. For the oil shale pyrolysis system without the introduction of zirconium-doped titanium oxysulfate composite bimetallic catalyst, except for the experiment using 1 mg of oil shale with an average particle size ≤74 μm, all other conditions were the same as those for the Py-EGA-MS experiment without the introduction of this bimetallic catalyst. Each experiment was performed three times under the same conditions to ensure the reliability and reproducibility of the results.

[0108] like Figure 6 As shown in Figure A, our Py-EGA-MS study indicates that after the pyrolysis of oil shale, two main peaks are observed. The first peak corresponds primarily to the decomposition of organic matter, while the second peak corresponds primarily to the decomposition of inorganic matter. After introducing a zirconium-doped titanium oxysulfate composite bimetallic catalyst, the highest point of the organic matter peak shifts to the low-temperature region, and the peak intensity of the total ion chromatogram increases. This indicates that the introduction of this bimetallic catalyst can indeed exert a catalytic effect, converting more organic matter into oil and gas products. The first peak region of the total ion chromatography (TIC) curve in Py-EGA-MS shows a complex but high-intensity signal in the mass spectrum of the pyrolysis products, as shown in Figure A. Figure 6 As shown in B. Through our detailed analysis, we can see that mass fragments with m / z values ​​of 43+14n (n = 0, 1, 2, etc.) and 41+14n (n = 0, 1, 2, etc.) are generally attributed to ionic fragments of aliphatic hydrocarbon chains. Furthermore, mass fragments with m / z values ​​of 109 and 95 are typically fragments of aromatic compounds, and m / z value of 81 is typically fragments of alkyl-substituted cyclohexenes. On the other hand, as... Figure 6 As shown in C, the mass spectra of the volatiles generated in the second peak region mainly yielded signals with m / z values ​​of 12, 16, 28, and 44, which are well matched with the standard mass spectrum of CO2, while the signals of other fragments were relatively weak.

[0109] Furthermore, we analyzed the product distribution of oil shale pyrolysis systems with or without zirconium-doped titanium oxysulfate composite bimetallic catalysts using rapid pyrolysis gas chromatography-mass spectrometry (Py-GC-MS) to further explore the catalytic effect of this bimetallic catalyst on oil shale pyrolysis. During the experiment, the total flow rate of high-purity helium used to purge the volatiles obtained in the pyrolyzer was 18.1 mL / min, and the flow rate of helium introduced into the molten silica GC column after separation was 1.37 mL / min. The m / z range was 50-550. For the catalytic pyrolysis system of oil shale, the weight ratio of oil shale to the bimetallic catalyst was 10:1. We placed oil shale samples with or without the bimetallic catalyst in sample cups and then placed them in a pyrolysis furnace at a preset temperature of 590 °C for 6 seconds. During the experiment, the GC column was initially held at 50°C for 5 min; subsequently, the temperature was increased from 50°C to 250°C at a rate of 3°C / min; finally, it was held at 250°C for 20 min. Each experiment was performed three times under the same conditions to ensure the reliability and reproducibility of the results. Peaks in the MS spectra were compared with peaks in the National Institute of Standards and Technology (NIST) mass spectrometry database to qualitatively match the chromatographic peaks observed in total ion chromatography (TIC). Data analysis and peak area integration were performed using GC-MS Postrun Analysis (GCMSsolution Version 4.3) software.

[0110] like Figure 7 As shown in Figure A, the introduction of the aforementioned bimetallic catalyst significantly increased the intensity and number of chromatographic peaks in regulating the composition and distribution of pyrolysis products. This indicates that the bimetallic catalyst can alter the distribution of pyrolysis products, which we will discuss in more detail below. We found that, as... Figure 7 As shown in Figure B, after introducing the above-mentioned bimetallic catalyst, the content of hydrocarbon compounds increased from 61.7% to 82.9%, an increase of 34.4%; in addition, the total amount of non-hydrocarbon compounds, that is, compounds containing N, O and S, decreased from 38.3% to 17.1%, a decrease of 55.4%. This indicates that the quality of the oil was greatly improved after catalytic pyrolysis.

[0111] Further research found that, for example Figure 8As shown in Figure A, the contents of N-containing, O-containing, and S-containing compounds were significantly reduced after the introduction of the bimetallic catalyst. Specifically, the content of N-containing compounds decreased from 4.0% to 0.4%, a reduction of 90.0%; the content of O-containing compounds decreased from 18.8% to 5.3%, a reduction of 71.8%; and the content of S-containing compounds decreased from 16.2% to 12.8%, a reduction of 21.0%. Furthermore, the introduction of this bimetallic catalyst reduced the content of alkanes from 16.3% to 9.7%, a reduction of 40.5%; increased the content of olefins from 24.3% to 38.8%, an increase of 59.7%; and increased the content of aromatics from 14.4% to 18.8%, an increase of 30.6%. Figure 8 As shown in Figure B, further analysis of aromatic hydrocarbons revealed that the introduction of this bimetallic catalyst reduced the content of polycyclic aromatic hydrocarbons (PAHs) from 1.1% to 0.7%, a decrease of 36.4%; while the content of monocyclic aromatic hydrocarbons (MOHs) increased from 13.3% to 18.1%, an increase of 36.1%. Specifically, the introduction of this bimetallic catalyst increased the contents of xylene and trimethylbenzene from 2.6% to 4.1% (an increase of 57.7%) and from 1.3% to 2.3% (an increase of 76.9%), respectively. More importantly, the introduction of this bimetallic catalyst significantly increased the content of toluene from 1.2% to 6.8%, an increase of 466.7%. Xylene and trimethylbenzene, especially toluene, are important and valuable platform chemicals widely used in the chemical and petroleum industries.

[0112] In addition, such as Figure 8 As shown in Figure C, we can see that after introducing this bimetallic catalyst, the short chain (≤C) 13 The content of aliphatic hydrocarbons increased significantly from 19.6% to 46.3%, a substantial increase of 136.2%. Furthermore, after introducing this bimetallic catalyst, the content of medium-chain (C...)... 14 -C 19 ) and long chains (C 20 -C 25 and ≥C 26 The content of aliphatic hydrocarbons decreased from 22.1% to 14.5% (a reduction of 34.4%) and from 5.6% to 3.3% (a reduction of 41.1%), respectively. This indicates that the bimetallic catalyst can also make the oil product lighter.

[0113] In summary, although there is no strict boundary between the catalytic performance and function of Brønsted (B) and Lewis (L) acids in oil shale pyrolysis, it is generally believed that B-acid sites primarily promote cracking, isomerization, oligomerization, and cyclization reactions through a carbocation chain mechanism. Lewis (L) acid sites primarily promote dehydrogenation and / or hydrogen transfer processes, using alkanes, alkenes, or cyclic hydrocarbons as precursors, through a carbon ion chain mechanism or a free radical mechanism, further promoting aromatization. In this bimetallic catalyst with numerous B-acid sites, B-acids promote the cracking of large molecules, for example, increasing the amount of short-chain aliphatic hydrocarbons. Furthermore, this catalyst exhibits anti-coking properties, possibly because B-acids, in addition to their cracking function, can also play a cyclization role, followed by dehydrogenation and aromatization under the influence of Lewis (L) acids. The cracking ability of the monocyclic aromatic side groups at the β-position preferentially exceeds the ability of the monocyclic aromatic hydrocarbons to undergo further deep aromatization. This contributes to the catalyst's anti-coking properties and also significantly increases the toluene content. The competition of these conversion pathways is a result of the synergistic effect of B-acid and L-acid sites.

[0114] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A zirconium-doped titanium oxysulfate composite bimetallic catalyst for processing fossil fuels or biomass, characterized in that, The active component of the bimetallic catalyst is selected from zirconium and titanium; The bimetallic catalyst has the general formula Zr. n (TiOSO4) m Both n and m are selected from positive numbers; the molar ratio of zirconium to titanium in the active component is 1:800-700:1; the content of the active component is 0.005-32wt%; the bimetallic catalyst is prepared by wet chemical-calcination method.

2. The application of the zirconium-doped titanium oxysulfate composite bimetallic catalyst according to claim 1 in the processing of fossil energy or biomass.

3. The application according to claim 2, wherein, The fossil energy source is selected from at least one of oil shale, coal, petroleum and oil sands, and the biomass is selected from at least one of agricultural crops, agricultural crop waste, forestry resources and animal manure; And / or, the processing method is selected from catalytic pyrolysis.

4. A method for processing fossil energy or biomass, characterized in that, The method includes: contacting a catalyst with fossil energy or biomass and carrying out a pyrolysis reaction in a non-oxidizing gas, inert atmosphere or oxygen-deficient atmosphere to obtain pyrolysis products; Wherein, the catalyst is selected from the zirconium-doped titanium oxysulfate composite bimetallic catalyst of claim 1; the non-oxidizing gas is selected from at least one of hydrogen, gaseous water, carbon dioxide and carbon monoxide; the inert atmosphere is selected from at least one of nitrogen, argon, helium, krypton, neon and xenon.

5. The method according to claim 4, wherein, The catalyst is in a weight ratio of 1:8000 to 20:1 with fossil energy or biomass. And / or, the fossil energy source is selected from at least one of oil shale, coal, petroleum and oil sands, and the biomass is selected from at least one of agricultural crops, agricultural crop waste, forestry resources and animal manure.

6. The method according to claim 5, wherein, The catalyst is in a weight ratio of 1:3000 to 2:1 with fossil energy or biomass.

7. The method according to claim 4, wherein, The conditions for the pyrolysis reaction include: a temperature of 35℃-1000℃, a time of 6s-30 days, and a heating rate of 1 / 6℃ / s-50℃ / s.

8. The method according to claim 4, wherein, The inert atmosphere is nitrogen.

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