Nickel-based catalyst and its preparation method and application

Abstract

The present invention relates to the technical field of catalyst preparation, and discloses a nickel-based catalyst, its preparation method, and application. The nickel-based catalyst comprises a carrier, an active component, and a promoter; the active component is nickel and nickel oxide; the promoter is selected from one or more oxides of Zn, Na, Mg, Zr, K, and Cu; and the nickel oxide is selected from one or more oxides of NiO, Ni3O4, and Ni2O3. This nickel-based catalyst exhibits bifunctional activity, promoting both oxygen adsorption and hydrogen activation, thereby further enhancing the catalytic activity and deoxidation efficiency of the nickel-based catalyst.

Description

Technical Field

[0001] The present invention relates to the technical field of catalyst preparation, and in particular to a nickel-based catalyst and a preparation method and application thereof. Background Art

[0002] Catalytic oxidation is one of the most common chemical reactions in chemical production. Incomplete reactions between feedstocks (low-carbon hydrocarbons) and oxidants (such as air, oxygen, and ozone) lead to significant accumulation of oxidants during the recycling of the feedstock, which in turn poses a significant risk of explosion during the chemical production process. The "Petrochemical Industry Flammable Gas Emission System Design Specification" stipulates that flammable gases with an oxygen content greater than 2% (v%) should not be discharged into the plant-wide flammable gas emission system. Therefore, the efficient treatment of oxygen in oxygen-containing tail gas has become a critical issue that needs to be addressed.

[0003] Currently, the primary method for treating feed gases containing hydrocarbons and oxygen is to dilute them with inert gases. This not only increases operating costs (due to the large amount of nitrogen consumed), but also causes environmental pollution through VOC emissions. In recent years, catalytic oxidation has been widely studied due to its significant economic, environmental, and energy-saving advantages. However, the catalysts commonly used in catalytic oxidation are all precious metals (Pt, Pd, Au, Ir, or Ru), which are expensive and still suffer from low deep deoxygenation efficiency. Therefore, the development of non-precious metal catalysts with high catalytic oxidation activity has attracted widespread attention from researchers.

[0004] Patent CN101745391B discloses a catalyst for removing trace oxygen from catalytic cracking dry gas. The catalyst comprises a primary catalytic active component and a co-catalytic active component. The primary catalytic active component is the precious metal palladium, the co-catalytic active component is selected from one or more of Ag, Au, Co, and Cr, and the support is selected from alumina, activated carbon, silicon oxide, or a molecular sieve. However, the catalyst can only deoxygenate high-hydrogen dry gas and can only react with trace oxygen at a relatively high reaction pressure (2.0 MPa) and a high hydrogen content to achieve deep deoxygenation.

[0005] In terms of the preparation of deoxygenation catalysts, most of the catalysts reported so far are concentrated on precious metal catalysts. However, precious metals are expensive and scarce, and cannot be promoted on a large scale in the field of olefin deoxygenation. In addition, the deoxygenation efficiency of existing olefin deoxygenation catalysts is low, which seriously limits the large-scale commercialization process of catalytic oxidation. Summary of the Invention

[0006] The purpose of the present invention is to overcome the problems existing in the prior art in the field of olefin deoxygenation, such as low deoxygenation efficiency of deoxygenation catalysts and high price of precious metal catalysts, and to provide a nickel-based catalyst and its preparation method and application. The nickel-based catalyst has bifunctional activity, which can promote oxygen adsorption and hydrogen activation at the same time, thereby further improving the catalytic activity of the nickel-based catalyst and improving the deoxygenation efficiency of the catalyst.

[0007] In order to achieve the above object, the present invention provides a nickel-based catalyst, which comprises a carrier, an active component and an additive;

[0008] The active components are nickel and nickel oxide;

[0009] The nickel oxide compound is selected from one or more of NiO, Ni3O4 and Ni2O3;

[0010] The auxiliary agent is selected from one or more oxides of Zn, Na, Mg, Zr, K and Cu.

[0011] Preferably, the molar ratio of nickel element to nickel oxide in the active component is 0.2-5:1.

[0012] Preferably, the active component is a combination of Ni and NiO, and the molar ratio of Ni to NiO is 1-2:1; or

[0013] The active component is a combination of nickel and Ni3O4, and the molar ratio of nickel to Ni3O4 is 0.2-5:1; or

[0014] The active component is a combination of nickel and Ni2O3, and the molar ratio of nickel to Ni2O3 is 0.4-5:1; or

[0015] When the active components are nickel, NiO and Ni2O3, the molar ratio of nickel, NiO and Ni2O3 is 0.4-4:0.4-8:1; or

[0016] When the active components are nickel, NiO and Ni3O4, the molar ratio of nickel, NiO and Ni3O4 is 0.5-5:0.5-6:1; or

[0017] When the active components are nickel, Ni3O4 and Ni2O3, the molar ratio of nickel, Ni3O4 and Ni2O3 is 0.25-4:0.25-4:1.

[0018] Preferably, the carrier is selected from one or more of Al2O3, SiO2, activated carbon and molecular sieve.

[0019] A second aspect of the present invention provides a method for preparing a nickel-based catalyst, the method comprising the following steps:

[0020] (1) immersing the support in a solution containing a nickel source and a promoter precursor, followed by solid-liquid separation;

[0021] (2) calcining the solid phase obtained in step (1), and then reducing the calcined product.

[0022] Preferably, the calcination conditions include: temperature of 300-550° C. and time of 3-6 hours.

[0023] Preferably, the reduction conditions include: temperature of 200-500° C., time of 3-12 h, and pressure of 0.1-0.25 MPa.

[0024] Preferably, the heating rate of the reduction process is 2-15°C / min.

[0025] Preferably, the auxiliary agent precursor is selected from one or more of Zn salt, Na salt, Mg salt, Zr salt, K salt and Cu salt.

[0026] Preferably, the carrier is selected from one or more of Al2O3, SiO2, activated carbon and molecular sieve.

[0027] Preferably, the reducing gas used in the reduction process is H2, a mixture of H2 and protective gas, or a mixture of H2 and CO;

[0028] Preferably, the H2 content in the mixture of H2 and protective gas is 5-20 vol%.

[0029] Preferably, the molar ratio of the nickel source, the auxiliary agent precursor and the carrier is 20:1-5:100, wherein the nickel source and the auxiliary agent precursor are calculated as metal elements.

[0030] The third aspect of the present invention provides a nickel-based catalyst prepared by the above method.

[0031] A fourth aspect of the present invention provides a use of the nickel-based catalyst in removing oxygen.

[0032] A fifth aspect of the present invention provides a method for deoxygenating olefins, comprising: mixing a feed gas containing hydrocarbon gas and oxygen with hydrogen, and then mixing and contacting the resulting mixed gas with a catalyst to perform a deoxygenation reaction;

[0033] The hydrogen content in the mixed gas is 0.1-1 vol%, the oxygen content in the raw gas is 0.1-0.5 vol%, and the catalyst is the above-mentioned nickel-based catalyst.

[0034] Preferably, the pressure of the deoxygenation reaction is 0.1-0.3 MPa.

[0035] The active components of the nickel-based catalyst of the present invention are a composite of metal element Ni and nickel oxide. The non-precious metal Ni-based catalyst is used as a precursor. By effectively controlling the composition of the active components of the catalyst and the ratio of nickel element to nickel oxide in the active components, a bifunctional Ni-Ni catalyst surface is efficiently constructed. x O y The active phase enables the nickel-based catalyst of the present invention to not only promote the adsorption of oxygen in the catalytic oxidation reaction of olefins, but also promote the activation of hydrogen by the nickel-based catalyst, and has high H2 activation ability and O2 adsorption-activation ability, thereby further promoting the combination of oxygen and hydrogen in the feed gas to achieve the purpose of deep deoxygenation;

[0036] In addition, the additive used in the nickel-based catalyst of the present invention can maintain the phase structure of the active component and can also increase the content of the active phase through electron exchange between the additive and the active component, thereby further improving the catalytic activity of the catalyst, that is, improving the deoxidation efficiency of the nickel-based catalyst;

[0037] The nickel-based catalyst of the present invention requires a lower reaction pressure when removing oxygen from the raw gas (a mixture containing hydrocarbon gas and oxygen), and also reduces the requirement for hydrogen concentration. The low required hydrogen content further prevents the occurrence of side reactions such as hydrogen and hydrocarbon gas during the deoxygenation process, while improving the denitration efficiency of the raw gas and further reducing the oxygen content in the final treated tail gas.

[0038] Furthermore, the raw material used in the nickel-based catalyst of the present invention is nickel-based metal, which greatly reduces the cost of raw materials compared to precious metals Pt or Pd, and at the same time has excellent deoxidation efficiency, making it more convenient for industrial promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 Schematic diagram of the nickel-based catalyst of the present invention. DETAILED DESCRIPTION

[0040] The following describes the specific embodiments of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0041] The endpoints of the ranges and any values ​​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 endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0042] In the present invention, unless otherwise specified, "space velocity" refers to "volume space velocity"; and "pressure" refers to absolute pressure.

[0043] The present invention provides a nickel-based catalyst, the specific structure of which is shown in FIG. Figure 1 The nickel-based catalyst comprises a carrier, an active component and an auxiliary agent (not shown in the figure). The active component and the auxiliary agent are attached to the surface of the carrier.

[0044] In the present invention, the active components of the nickel-based catalyst are nickel and nickel oxide, wherein the nickel oxide is selected from one or more of NiO, Ni3O4, and Ni2O3. By adjusting the ratio of nickel and nickel oxide in the active components and the type of active components, the surface of the nickel-based catalyst is endowed with a bifunctional active phase, which promotes both oxygen adsorption and hydrogen activation, thereby improving the catalyst's deoxidation efficiency.

[0045] In the nickel-based catalyst of the present invention, the additive is selected from one or more oxides of Zn, Na, Mg, Zr, K, and Cu. Specifically, the additive is present in the form of a metal oxide. The additive increases the content of the active component through electron exchange with the active component, maintains the configuration of the active component, and enhances the catalytic activity of the nickel-based catalyst.

[0046] In the nickel-based catalyst of the present invention, the molar ratio of the carrier, the active component and the auxiliary agent is 100:20:1-5, wherein the active component and the auxiliary agent are both calculated as metal elements.

[0047] In a preferred embodiment, the molar ratio of nickel to nickel oxide in the active component is 0.2-5:1, preferably 0.21-3:1. Specifically, the molar ratio of nickel to nickel oxide in the active component can be 0.2:1, 0.22:1, 0.25:1, 0.4:1, 0.5:1, 0.6:1, 1:1, 1.5:1, 2:1, 2.5:1 or 3:1.

[0048] In a preferred embodiment, the active component is a combination of elemental Ni and NiO, and the molar ratio of elemental Ni to NiO is 1-2:1, preferably 1.2-1.8:1, and more preferably 1.5:1. Specifically, the molar ratio of elemental Ni to NiO in the active component can be 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, or 1.8:1.

[0049] In a preferred embodiment, the active component is a combination of elemental Ni and Ni3O4, and the molar ratio of elemental Ni to Ni3O4 is 0.2-5:1, preferably 0.5-3:1, and more preferably 0.6-2.5:1. Specifically, the molar ratio of elemental Ni to Ni3O4 in the active component can be 0.5:1, 0.6:1, 0.7:1, 1:1, 1.5:1, 2:1, or 3:1.

[0050] In a preferred embodiment, the active component is a combination of elemental Ni and Ni2O3, and the molar ratio of elemental Ni to Ni2O3 is 0.4-5:1, preferably 0.7-3:1, and more preferably 0.75-2.5:1. Specifically, the molar ratio of elemental Ni to Ni2O3 in the active component can be 0.7:1, 1:1, 1.5:1, 1.6:1, 2:1, 2.5:1, or 3:1.

[0051] In a preferred embodiment, when the active components are nickel, NiO, and Ni2O3, the molar ratio of nickel, NiO, and Ni2O3 is 0.4-4:0.4-8:1, preferably 0.4-2:1-3:1, and more preferably 0.5-1:1.5-2.5:1. Specifically, the molar ratio of nickel, NiO, and Ni2O3 in the active components can be 0.5:1.5:1, 0.5:2:1, 0.8:1.5:1, or 1:2.5:1.

[0052] In a preferred embodiment, when the active components are nickel, NiO, and Ni3O4, the molar ratio of nickel, NiO, and Ni3O4 is 0.5-5:0.5-6:1, preferably 1-3:1-4:1, and more preferably 1.5-2.5:2-4:1. Specifically, the molar ratio of nickel, NiO, and Ni3O4 in the active components can be 1.5:2:1, 2:3:1, 2.5:3.5:1, or 2.5:4:1.

[0053] In a preferred embodiment, when the active components are nickel, Ni3O4, and Ni2O3, the molar ratio of nickel, Ni3O4, and Ni2O3 is 0.25-4:0.25-4:1, preferably 0.5-1.5:0.3-2:1, and more preferably 0.55-1.2:0.3-1.5:1. Specifically, the molar ratio of nickel, Ni3O4, and Ni2O3 in the active components can be 0.5:0.3:1, 0.5:0.5:1, 1:1:1, or 1.5:2:1.

[0054] In the nickel-based catalyst described in the present invention, the Ni element and nickel oxide in the active component form a composite active center. Compared with a single active center catalyst, it has more catalytic active sites and more functions. When catalyzing the deoxygenation of olefins, it can not only promote the adsorption of oxygen, but also promote the activation of hydrogen, thereby comprehensively improving the deoxygenation efficiency of the catalyst.

[0055] In the nickel-based catalyst of the present invention, the support can be selected from common supports in the art. In a preferred embodiment, the support is selected from one or more of Al2O3, SiO2, activated carbon, and molecular sieves. Specifically, the activated carbon can be conventional activated carbon in the art, and the molecular sieve can be selected from at least one of an HZSM-5 molecular sieve support, a 4A molecular sieve support, an MCM-22 molecular sieve support, and a Y-type molecular sieve support.

[0056] According to some embodiments of the present invention, the nickel-based catalyst comprises a support, an active component supported on the support, and a promoter. The active component is elemental nickel and at least one of NiO, Ni3O4, and Ni2O3; the promoter is selected from one or more oxides of Zn, Na, Mg, Zr, K, and Cu; and the support is selected from one or more of Al2O3, SiO2, activated carbon, and molecular sieves.

[0057] According to other embodiments of the present invention, the nickel-based catalyst comprises a support, an active component supported on the support, and a promoter. The active component is elemental nickel and at least one of NiO, Ni3O4, and Ni2O3; the promoter is selected from one or more oxides of Zn, Na, Mg, Zr, K, and Cu; and the support is selected from one or more oxides of Al2O3, SiO2, activated carbon, and molecular sieves. In the nickel-based catalyst, the weight ratio of the support, active component, and promoter is 100:20:1-5, where the active component and promoter are both calculated as metal elements.

[0058] The present invention also provides a method for preparing the nickel-based catalyst, the method comprising the following steps:

[0059] (1) immersing the support in a solution containing a nickel source and a promoter precursor, followed by solid-liquid separation;

[0060] (2) calcining the solid phase obtained in step (1), and then reducing the calcined product.

[0061] In a specific embodiment, before immersing the support in the solution containing the nickel source and the auxiliary agent precursor, the nickel source and the auxiliary agent precursor may be dissolved in water to obtain a solution containing the nickel source and the auxiliary agent precursor.

[0062] In a preferred embodiment, in step (1), the impregnation method can be excess impregnation, distributed impregnation or equal volume impregnation.

[0063] In a preferred embodiment, the nickel source is selected from NiCl2 or Ni(NO3)2.

[0064] In a preferred embodiment, the auxiliary agent precursor is a soluble salt, preferably one or more selected from the group consisting of Zn salts, Na salts, Mg salts, Zr salts, K salts, and Cu salts. Specifically, the auxiliary agent precursor is one or more selected from the group consisting of Zn(NO3)2, NaNO3, Mg(NO3)2, Zr(NO3)4, KNO3, and Cu(NO3)2.

[0065] In a preferred embodiment, the carrier is selected from one or more of Al2O3, SiO2, activated carbon and molecular sieve.

[0066] In some embodiments, in the nickel-based catalyst, the weight ratio of the support, the active component, and the auxiliary agent is 100:20:1-5, wherein the active component and the auxiliary agent are both calculated as metal elements.

[0067] In a specific embodiment, in step (1), the solid phase obtained after solid-liquid separation needs to be dried at a temperature of 80-120° C. for a drying time of 8-15 h.

[0068] In a specific embodiment, in order to further improve the catalytic performance of the nickel-based catalyst finally prepared, in step (2), the calcination conditions include: a temperature of 300-550°C, preferably 400-550°C; and a time of 3-6 hours, preferably 3.5-5.5 hours. Specifically, the calcination temperature can be 300°C, 350°C, 400°C, 450°C, 500°C, or 550°C; and the calcination time can be 3 hours, 4 hours, 5 hours, or 6 hours.

[0069] In the present invention, the calcined material is subjected to a reduction treatment, and the conditions of the reduction process are further controlled so that the surface of the nickel-based catalyst has bifunctional Ni metal and Ni oxide active centers, and the catalytic activity of the active component is further regulated by controlling the composition of Ni oxide in the active component and the content ratio between Ni metal and Ni oxide. As a result, the nickel-based catalyst of the present invention can promote the adsorption of oxygen and the activation of hydrogen, thereby further promoting the reaction between oxygen and hydrogen in the feed gas, improving the deoxidation effect of the nickel-based catalyst, and achieving deep deoxidation of the feed gas.

[0070] In the present invention, the auxiliary agent conducts electron flow with the active component during the calcination and reduction process, promotes the formation of the active phase and increases the content of the active component, and further maintains the configuration of the active component, thereby further improving the catalytic activity of the nickel-based catalyst, thereby improving the deoxygenation efficiency of the nickel-based catalyst in the catalytic oxidation of olefins.

[0071] In a preferred embodiment, to further improve the deoxidation efficiency of the nickel-based catalyst, the reduction conditions include: a temperature of 200-500°C, preferably 350-450°C; a time of 3-12 hours, preferably 6-10 hours; and a pressure of 0.1-0.25 MPa. Specifically, the reduction temperature can be 200°C, 300°C, 400°C, or 500°C; the reduction time can be 3 hours, 5 hours, 8 hours, 10 hours, or 12 hours; and the reduction pressure can be 0.1 MPa, 0.15 MPa, 0.18 MPa, 0.2 MPa, 0.23 MPa, or 0.25 MPa.

[0072] In a preferred embodiment, in order to further improve the catalytic efficiency of the nickel-based catalyst, the heating rate of the reduction process is controlled to be 2-15°C / min, more preferably 3-10°C / min. The heating rate of the reduction process refers to the heating rate of the process of raising the ambient temperature of the material to the reduction target temperature during the reduction process. Specifically, the heating rate of the reduction process can be 2°C / min, 5°C / min, 6°C / min, 8°C / min, 10°C / min, 12°C / min, or 15°C / min.

[0073] In the present invention, the reducing gas used in the reduction process is H2, a mixture of H2 and protective gas, or a mixture of H2 and CO; specifically, the reducing gas can be pure H2, a mixture of H2 and protective gas, or a mixture of H2 and CO.

[0074] In a preferred embodiment, when the reducing gas is a mixture of H2 and protective gas, the H2 content in the mixture is 5-20 vol%, preferably 5-15 vol%. Specifically, the H2 content in the reducing gas can be 5 vol%, 10 vol%, 15 vol% or 20 vol%.

[0075] In a specific embodiment, the molar ratio of the nickel source, the auxiliary agent precursor and the carrier is 20:1-5:100, wherein the nickel source and the auxiliary agent precursor are calculated as metal elements.

[0076] The present invention further provides a nickel-based catalyst prepared by the above preparation method.

[0077] The present invention further provides a use of the nickel-based catalyst in removing oxygen. Preferably, the nickel-based catalyst is used to remove oxygen from a feed gas containing hydrocarbon gas and oxygen by catalytic oxidation, wherein the oxygen content in the feed gas is 0.1-0.5 vol%.

[0078] The present invention may also provide a method for deoxygenating olefins, comprising: mixing a feed gas containing hydrocarbon gas and oxygen with hydrogen, and then mixing and contacting the obtained mixed gas with a catalyst to perform a deoxygenation reaction.

[0079] In a specific embodiment, the hydrocarbon gas may be at least one of C1-C4 alkanes, C2-C4 alkenes and C2-C4 alkynes.

[0080] In a specific embodiment, the content of hydrogen in the mixed gas is 0.1-1 vol%, preferably 0.3-0.6 vol%; the content of oxygen in the raw gas is 0.1-0.5 vol%; and the catalyst is the above-mentioned nickel-based catalyst.

[0081] In the present invention, the nickel-based catalyst can remove low-concentration oxygen in the raw gas and achieve deep deoxygenation of the raw gas. In addition, in the presence of the nickel-based catalyst, the deoxygenation reaction does not need to be carried out under conditions of a high hydrogen content, further avoiding the reaction of hydrogen with hydrocarbon gases in the raw gas, reducing the generation of side reactions, and further achieving deep deoxygenation of the raw gas.

[0082] In the present invention, the pressure of the deoxygenation reaction is 0.1-0.3 MPa. Specifically, the pressure of the deoxygenation reaction can be 0.1 MPa (normal pressure), 0.15 MPa, 0.2 MPa, 0.25 MPa or 0.3 MPa. The deoxygenation reaction requires a lower pressure and milder conditions.

[0083] In a specific embodiment, the nickel-based catalyst of the present invention can remove low-content oxygen in the feed gas, and can achieve deep removal of oxygen under conditions of lower hydrogen content and lower reaction pressure.

[0084] The present invention will be described in detail below through examples, but the scope of protection of the present invention is not limited thereto. The examples are implemented under the premise of the technical solution of the present invention, and detailed implementation methods and specific operating processes are given, but the scope of protection of the present invention is not limited to the following examples.

[0085] The experimental methods in the following examples, unless otherwise specified, are all conventional methods in the art. The experimental materials used in the following examples, unless otherwise specified, are all commercially available.

[0086] Example 1

[0087] (1) Ni(NO3)2 and Zn(NO3)2 are dissolved in deionized water to obtain a solution containing Ni(NO3)2 and Zn(NO3)2; then, a carrier Al2O3 is impregnated in the solution of Ni(NO3)2 and Zn(NO3)2 by an over-impregnation method, followed by solid-liquid separation, and the obtained solid phase is dried at 120°C for 10 hours; the weight ratio of Ni(NO3)2, Zn(NO3)2 and carrier Al2O3 is 20:5:100 (the weight of Ni(NO3)2 and Zn(NO3)2 is calculated as metal elements);

[0088] (2) The dried solid phase was calcined at a temperature of 550°C for 3 h. The calcined product was then placed in a fixed bed reactor for reduction at a temperature of 450°C, a reducing atmosphere of pure H2, a reduction time of 6 h, a reducing pressure of 0.2 MPa, and a heating rate of 2°C / min to obtain a Ni-based catalyst. In-situ XPS characterization revealed that the active components of the Ni-based deoxidation catalyst were Ni and NiO, with a molar ratio of 3:2. XRD and XPS characterization revealed that the additive was Zn oxide.

[0089] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0090] (4) The feed gas (composed of 99.25 vol% ethylene, 0.25 vol% oxygen and 0.5 vol% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000 h -1 , reaction pressure 0.2MPa, reaction temperature 120℃.

[0091] Example 2

[0092] (1) Ni(NO3)2 and NaNO3 are dissolved in deionized water to obtain a solution containing Ni(NO3)2 and NaNO3; then, the carrier Al2O3 is impregnated in the Ni(NO3)2 and NaNO3 solution by an equal volume impregnation method, followed by solid-liquid separation, and the obtained solid phase is dried at 120°C for 10 hours; the weight ratio of Ni(NO3)2, NaNO3 and the carrier Al2O3 is 20:5:100 (the weight of Ni(NO3)2 and NaNO3 is calculated as metal elements);

[0093] (2) The dried solid phase was calcined at a temperature of 550°C for 4 hours. The calcined product was then placed in a fixed bed reactor for reduction at a temperature of 400°C, a reducing atmosphere of pure H2, a reduction time of 8 hours, a reducing pressure of 0.1 MPa, and a heating rate of 3°C / min to obtain a Ni-based catalyst. In-situ XPS characterization revealed that the active components of the Ni-based deoxidation catalyst were Ni and Ni3O4, with a molar ratio of 3:5. XRD and XPS characterization revealed that the additive was Na oxide.

[0094] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0095] (4) The feed gas (composed of 99.25 vol% ethylene, 0.25 vol% oxygen and 0.5 vol% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000 h -1 , reaction pressure 0.2MPa, reaction temperature 120℃.

[0096] Example 3

[0097] (1) Ni(NO3)2 and Mg(NO3)2 are dissolved in deionized water to obtain a solution containing Ni(NO3)2 and Mg(NO3)2; then, a carrier SiO2 is impregnated in the Ni(NO3)2 and Mg(NO3)2 solution by an equal volume impregnation method, followed by solid-liquid separation, and the obtained solid phase is dried at 120°C for 10 hours; the weight ratio of Ni(NO3)2, Mg(NO3)2 and carrier SiO2 is 20:5:100 (the weight of Ni(NO3)2 and Mg(NO3)2 is calculated as metal elements);

[0098] (2) The dried solid phase was calcined at 450°C for 4 hours. The calcined product was then placed in a fixed bed reactor for reduction at 400°C in a pure H2 atmosphere for 8 hours, at a pressure of 0.15 MPa, and at a heating rate of 3°C / min to obtain a Ni-based catalyst. In-situ XPS characterization revealed that the active components of the Ni-based deoxidation catalyst were Ni and Ni2O3, with a molar ratio of 5:2. XRD and XPS characterization revealed that the additive was Mg oxide.

[0099] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0100] (4) The feed gas (composed of 99.25 vol% ethylene, 0.25 vol% oxygen and 0.5 vol% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000 h -1 , reaction pressure 0.2MPa, reaction temperature 120℃.

[0101] Example 4

[0102] (1) Ni(NO3)2 and Zr(NO3)2 are dissolved in deionized water to obtain a solution containing Ni(NO3)2 and Zr(NO3)2; then, a carrier SiO2 is impregnated in the Ni(NO3)2 and Zr(NO3)2 solution by an equal volume impregnation method, followed by solid-liquid separation, and the obtained solid phase is dried at 120°C for 10 hours; the weight ratio of Ni(NO3)2, Zr(NO3)2 and carrier SiO2 is 20:3:100 (the weight of Ni(NO3)2 and Zr(NO3)2 is calculated as metal elements);

[0103] (2) The dried solid phase is calcined at a temperature of 450°C for 4 hours; the calcined product is then placed in a fixed bed reactor for reduction at a temperature of 400°C in a reducing atmosphere of a mixture of 15 vol% H2 and 85 vol% N2 for 8 hours, at a pressure of 0.1 MPa, and at a heating rate of 3°C / min to obtain a Ni-based catalyst; in-situ XPS characterization indicates that the active components of the Ni-based deoxidation catalyst are Ni, NiO, and Ni3O4, and the molar ratio is 2:3:1. XRD and XPS characterization indicate that the auxiliary agent is Zr oxide;

[0104] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0105] (4) The feed gas (composed of 99.25 vol% ethylene, 0.25 vol% oxygen and 0.5 vol% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000 h -1 , reaction pressure is 0.25MPa, and reaction temperature is 130℃.

[0106] Example 5

[0107] (1) Ni(NO3)2 and KNO3 are dissolved in deionized water to obtain a solution containing Ni(NO3)2 and KNO3; then, the carrier activated carbon is impregnated in the Ni(NO3)2 and KNO3 solution by an over-impregnation method, followed by solid-liquid separation, and the obtained solid phase is dried at 120°C for 10 hours; the weight ratio of Ni(NO3)2, KNO3 and the carrier activated carbon is 20:3:100 (the weight of Ni(NO3)2 and KNO3 is calculated as metal elements);

[0108] (2) The dried solid phase was calcined at 450°C for 4 hours. The calcined product was then placed in a fixed bed reactor for reduction at 400°C in a pure H2 atmosphere for 8 hours, at a pressure of 0.1 MPa, and at a heating rate of 3°C / min to obtain a Ni-based catalyst. In-situ XPS characterization revealed that the active components of the Ni-based deoxidation catalyst were Ni, NiO, and Ni2O3, with a molar ratio of 2:6:3. XRD and XPS characterization revealed that the additive was K oxide.

[0109] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0110] (4) The feed gas (composed of 99.25 vol% ethylene, 0.25 vol% oxygen and 0.5 vol% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000 h -1 , reaction pressure is 0.25MPa, and reaction temperature is 120℃.

[0111] Example 6

[0112] (1) Ni(NO3)2 and Cu(NO3)2 are dissolved in deionized water to obtain a solution containing Ni(NO3)2 and Cu(NO3)2; then, a carrier HZSM-5 molecular sieve is impregnated in the solution of Ni(NO3)2 and Cu(NO3)2 by an over-impregnation method, followed by solid-liquid separation, and the obtained solid phase is dried at 120°C for 10 hours; the metal weight ratio of the amount of Ni(NO3)2, Cu(NO3)2 and the carrier HZSM-5 molecular sieve is 20:4:100 (the weight of Ni(NO3)2 and Cu(NO3)2 is calculated as metal elements);

[0113] (2) The dried solid phase is calcined at a temperature of 550°C for 4 hours; the calcined product is then placed in a fixed bed reactor for reduction at a temperature of 400°C in a reducing atmosphere of a mixture of 10 vol% H2 and 90 vol% N2 for 8 hours, a reducing pressure of 0.25 MPa, and a heating rate of 3°C / min to obtain a Ni-based catalyst; in-situ XPS characterization indicates that the active components of the Ni-based deoxidation catalyst are Ni, Ni3O4, and Ni2O3, and the molar ratio is 2:3:2. XRD and XPS characterization indicate that the auxiliary agent is Cu oxide;

[0114] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0115] (4) The feed gas (composed of 99.25% ethylene, 0.25% oxygen and 0.5% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000h -1 , reaction pressure 0.3MPa, reaction temperature 120℃.

[0116] Example 7

[0117] (1) Ni(NO3)2 and Cu(NO3)2 are dissolved in deionized water to obtain a solution containing Ni(NO3)2 and Cu(NO3)2; then, the carrier MCM-22 molecular sieve is impregnated in the Ni(NO3)2 and Cu(NO3)2 solution by a distributed impregnation method, followed by solid-liquid separation, and the obtained solid phase is dried at 120°C for 10 hours; the metal weight ratio of the amount of Ni(NO3)2, Cu(NO3)2 and the carrier MCM-22 molecular sieve is 20:4:100 (the weight of Ni(NO3)2 and Cu(NO3)2 is calculated as metal elements);

[0118] (2) The dried solid phase was calcined at a temperature of 550°C for 4 hours. The calcined product was then placed in a fixed bed reactor for reduction at a temperature of 400°C, a reducing atmosphere of pure H2, a reduction time of 8 hours, a reducing pressure of 0.1 MPa, and a heating rate of 3°C / min to obtain a Ni-based catalyst. In-situ XPS characterization revealed that the active components of the Ni-based deoxidation catalyst were Ni, Ni3O4, and Ni2O3, with a molar ratio of 2:1:3. XRD and XPS characterization revealed that the additive was Cu oxide.

[0119] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0120] (4) The feed gas (composed of 99.25% ethylene, 0.25% oxygen and 0.5% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000h -1 , reaction pressure is 0.25MPa, and reaction temperature is 120℃.

[0121] Example 8

[0122] (1) Ni(NO3)2 and NaNO3 are dissolved in deionized water to obtain a solution containing Ni(NO3)2 and NaNO3; then, a carrier Y-type molecular sieve is impregnated in the solution of Ni(NO3)2 and NaNO3 by a distributed impregnation method, followed by solid-liquid separation, and the obtained solid phase is dried at 120°C for 10 hours; the weight ratio of Ni(NO3)2, NaNO3 and carrier Y-type molecular sieve is 20:5:100 (the weight of Ni(NO3)2 and NaNO3 is calculated as metal elements);

[0123] (2) The dried solid phase was calcined at a temperature of 550°C for 4 hours; the calcined product was then placed in a fixed bed reactor for reduction at a temperature of 400°C in a reducing atmosphere of a mixture of 5 vol% H2 and 95 vol% N2 for 10 hours, a reducing pressure of 0.15 MPa, and a heating rate of 3°C / min to obtain a Ni-based catalyst; in-situ XPS characterization revealed that the active components of the Ni-based deoxidation catalyst were Ni and Ni3O4, with a molar ratio of 5:2, and XRD and XPS characterization revealed that the auxiliary agent was Na oxide;

[0124] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0125] (4) The feed gas (composed of 99.25% ethylene, 0.25% oxygen and 0.5% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000h -1 , reaction pressure is 0.25MPa, and reaction temperature is 120℃.

[0126] Example 9

[0127] (1) Ni(NO3)2 and NaNO3 are dissolved in deionized water to obtain a solution containing Ni(NO3)2 and NaNO3; then, a mixture of a Y-type molecular sieve carrier and an MCM-22 molecular sieve (the weight ratio of the Y-type molecular sieve carrier to the MCM-22 molecular sieve is 1:1) is impregnated in the Ni(NO3)2 and NaNO3 solution by an over-impregnation method, followed by solid-liquid separation, and the obtained solid phase is dried at 120°C for 10 hours; the weight ratio of Ni(NO3)2, NaNO3 and the Y-type molecular sieve carrier is 20:5:100 (the weight of Ni(NO3)2 and NaNO3 is calculated as metal elements);

[0128] (2) The dried solid phase was calcined at a temperature of 450°C for 4 hours. The calcined product was then placed in a fixed bed reactor for reduction at a temperature of 400°C in a reducing atmosphere of a mixture of 5 vol% H2 and 95 vol% N2 for 8 hours. The reduction pressure was 0.1 MPa and the heating rate during reduction was 3°C / min to obtain a Ni-based catalyst. In-situ XPS characterization revealed that the active components of the Ni-based deoxidation catalyst were Ni and Ni3O4, with a molar ratio of 3:2. XRD and XPS characterization revealed that the auxiliary agent was Na oxide.

[0129] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0130] (4) The feed gas (composed of 99.25% ethylene, 0.25% oxygen and 0.5% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000h -1 , reaction pressure is 0.25MPa, and reaction temperature is 120℃.

[0131] Example 10

[0132] (1) Ni(NO3)2 and Mg(NO3)2 are dissolved in deionized water to obtain a solution containing Ni(NO3)2 and Mg(NO3)2; then, a mixture of HZSM-5 molecular sieve and MCM-22 molecular sieve (the weight ratio of HZSM-5 molecular sieve and MCM-22 molecular sieve is 1:1) is impregnated in the solution of Ni(NO3)2 and Mg(NO3)2 by an over-impregnation method, followed by solid-liquid separation, and the obtained solid phase is dried at 120°C for 10 hours; the metal ratio of Ni(NO3)2, Mg(NO3)2 and the carrier is 20:5:100 (the weight of Ni(NO3)2 and Mg(NO3)2 is calculated as metal elements);

[0133] (2) The dried solid phase was calcined at a temperature of 550°C for 4 hours. The calcined product was then placed in a fixed bed reactor for reduction at a temperature of 450°C in a reducing atmosphere of a mixture of 5 vol% H2 and 95 vol% N2 for 6 hours. The reduction pressure was 0.1 MPa and the heating rate during reduction was 3°C / min to obtain a Ni-based catalyst. In-situ XPS characterization revealed that the active components of the Ni-based deoxidation catalyst were Ni and Ni2O3, with a molar ratio of 3:4. XRD and XPS characterization revealed that the additive was Mg oxide.

[0134] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0135] (4) The feed gas (composed of 99.25% ethylene, 0.25% oxygen and 0.5% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000h -1 , reaction pressure is 0.25MPa, and reaction temperature is 120℃.

[0136] Comparative Example 1

[0137] (1) Ni(NO3)2 is dissolved in deionized water to obtain a Ni(NO3)2 solution; then, a carrier SiO2 is impregnated in the Ni(NO3)2 solution by an over-impregnation method, followed by solid-liquid separation, and the obtained solid phase is dried at 120°C for 10 hours; the metal weight ratio of the amount of Ni(NO3)2 to the carrier SiO2 is 20:100 (the weight of Ni(NO3)2 is calculated as the metal element);

[0138] (2) The dried solid phase was calcined at a temperature of 550°C for 4 hours. The calcined product was then placed in a fixed bed reactor for reduction at a temperature of 400°C, a reducing atmosphere of pure H2, a reduction time of 8 hours, a reducing pressure of 0.1 MPa, and a heating rate of 3°C / min to obtain a Ni-based catalyst. Characterization by in-situ XPS revealed that the active component of the Ni-based deoxidation catalyst was Ni.

[0139] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0140] (4) The feed gas (composed of 99.25% ethylene, 0.25% oxygen and 0.5% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000h -1 , reaction pressure is 0.25MPa, and reaction temperature is 120℃.

[0141] Comparative Example 2

[0142] (1) Ni(NO3)2 was dissolved in deionized water to obtain a Ni(NO3)2 solution; then, the carrier Al2O3 was impregnated in the Ni(NO3)2 solution by an equal volume impregnation method, followed by solid-liquid separation, and the obtained solid phase was dried at 120°C for 10 hours; the weight ratio of Ni(NO3)2 to the carrier Al2O3 was 10:100 (the weight of Ni(NO3)2 was calculated as the metal element);

[0143] (2) The dried solid phase was calcined at a temperature of 550°C for 4 hours; the calcined product was then placed in a fixed bed reactor for reduction at a temperature of 400°C in a reducing atmosphere of a mixture of 10 vol% H2 and 95 vol% N2 for 8 hours, at a pressure of 0.1 MPa, and at a heating rate of 3°C / min to obtain a Ni-based catalyst; in-situ XPS characterization revealed that the active component of the Ni-based deoxidation catalyst was Ni;

[0144] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0145] (4) The feed gas (composed of 99.25% ethylene, 0.25% oxygen and 0.5% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000h -1 , reaction pressure is 0.25MPa, and reaction temperature is 120℃.

[0146] Comparative Example 3

[0147] (1) Ni(NO3)2 and Ca(NO3)2 are dissolved in deionized water to obtain a solution containing Ni(NO3)2 and Ca(NO3)2; then, a carrier Y-type molecular sieve is impregnated in the solution of Ni(NO3)2 and NaNO3 by an over-impregnation method, followed by solid-liquid separation, and the obtained solid phase is dried at 120°C for 10 hours; the metal weight ratio of the amount of Ni(NO3)2, Ca(NO3)2 and the carrier Y-type molecular sieve is 20:5:100 (the weight of Ni(NO3)2 and Ca(NO3)2 is calculated as metal elements);

[0148] (2) The dried solid phase was calcined at 450°C for 4 hours; the calcined product was then placed in a fixed bed reactor for reduction at 400°C in a reducing atmosphere of a mixture of 5 vol% H2 and 95 vol% N2 for 8 hours, at a pressure of 0.1 MPa, and at a heating rate of 3°C / min to obtain a Ni-based catalyst; in-situ XPS characterization revealed that the active components of the Ni-based deoxidation catalyst were Ni and NiO, with a molar ratio of Ni:NiO = 15:1;

[0149] (3) After the reduction is completed, the bed temperature of the fixed bed reactor is lowered to room temperature, and the catalyst bed is purged with nitrogen for 30 minutes;

[0150] (4) The feed gas (composed of 99.25% ethylene, 0.25% oxygen and 0.5% hydrogen) was introduced into a fixed bed reactor for gas phase deoxygenation reaction. The deoxygenation reaction conditions were: reaction space velocity 2000h -1 , reaction pressure is 0.25MPa, and reaction temperature is 120℃.

[0151] Test Case

[0152] Gas chromatography was used to detect the oxygen content in the tail gas after final deoxygenation of Examples 1-10 and Comparative Examples 1-3, and the deoxygenation rate was calculated using the formula: (oxygen content in feed gas - oxygen content in tail gas) ÷ oxygen content in feed gas. The results are shown in Table 1.

[0153] Table 1

[0154]

[0155]

[0156] It can be seen from the results in Table 1 that in the olefin deoxygenation process, the nickel-based catalyst of the present invention has a higher deoxygenation rate and a better deoxygenation effect, and can achieve deep deoxygenation of the feed gas.

[0157] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A nickel-based catalyst, characterized in that The nickel-based catalyst comprises a carrier, an active component and an auxiliary agent, wherein the active component and the auxiliary agent are attached to the surface of the carrier, and the molar ratio of the carrier, the active component and the auxiliary agent is 100:20:1-5, wherein the active component and the auxiliary agent are both calculated as metal elements; The active components are nickel and nickel oxide, and the molar ratio of nickel to nickel oxide in the active components is 0.2-5:1; The nickel oxide is selected from one or more of NiO, Ni3O4 and Ni2O3; The auxiliary agent is selected from one or more oxides of Zn, Na, Mg, Zr, K and Cu.

2. The nickel-based catalyst according to claim 1, characterized in that The active component is a combination of nickel and NiO, and the molar ratio of nickel to NiO is 1-2:1; or The active component is a combination of nickel and Ni3O4, and the molar ratio of nickel to Ni3O4 is 0.2-5:1; or The active component is a combination of nickel and Ni2O3, and the molar ratio of nickel to Ni2O3 is 0.4-5:1; or When the active components are nickel, NiO and Ni2O3, the molar ratio of nickel, NiO and Ni2O3 is 0.4-4:0.4-8:1; or When the active components are nickel, NiO and Ni3O4, the molar ratio of nickel, NiO and Ni3O4 is 0.5-5:0.5-6:1; or When the active components are nickel, Ni3O4 and Ni2O3, the molar ratio of nickel, Ni3O4 and Ni2O3 is 0.25-4:0.25-4:

1.

3. The nickel-based catalyst according to claim 1, characterized in that The carrier is selected from one or more of Al2O3, SiO2, activated carbon and molecular sieve.

4. A method for preparing the nickel-based catalyst according to any one of claims 1 to 3, characterized in that: The method comprises the following steps: (1) Immersing the support in a solution containing a nickel source and a promoter precursor, followed by solid-liquid separation; (2) calcining the solid phase obtained in step (1), and then reducing the calcined product.

5. The method for preparing a nickel-based catalyst according to claim 4, wherein The calcination conditions include: temperature of 300-550° C. and time of 3-6 hours.

6. The method for preparing a nickel-based catalyst according to claim 4, wherein The reduction conditions include: temperature of 200-500° C., time of 3-12 h, and pressure of 0.1-0.25 MPa.

7. The method for preparing a nickel-based catalyst according to claim 4 or 6, characterized in that: The heating rate of the reduction process is 2-15°C / min.

8. The method for preparing a nickel-based catalyst according to claim 4, wherein The auxiliary agent precursor is selected from one or more of Zn salt, Na salt, Mg salt, Zr salt, K salt and Cu salt.

9. The method for preparing a nickel-based catalyst according to claim 4, wherein: The carrier is selected from one or more of Al2O3, SiO2, activated carbon and molecular sieve.

10. The method for preparing a nickel-based catalyst according to any one of claims 4, 6 or 7, characterized in that: The reducing gas used in the reduction process is H2, a mixture of H2 and protective gas, or a mixture of H2 and CO.

11. The method for preparing a nickel-based catalyst according to claim 10, wherein: The content of H2 in the mixed gas of H2 and protective gas is 5-20 vol%.

12. The method for preparing a nickel-based catalyst according to any one of claims 4, 8 or 9, characterized in that: The molar ratio of the nickel source, the auxiliary agent precursor and the carrier is 20:1-5:100, wherein the nickel source and the auxiliary agent precursor are calculated as metal elements.

13. Use of the nickel-based catalyst according to any one of claims 1 to 3 in removing oxygen.

14. A method for deoxygenating olefins, characterized in that: The method comprises: mixing a raw gas containing hydrocarbon gas and oxygen with hydrogen gas, and then mixing and contacting the obtained mixed gas with a catalyst to perform a deoxygenation reaction; The hydrogen content in the mixed gas is 0.1-1 vol%, and the oxygen content in the raw gas is 0.1-0.5 vol%. The catalyst is the nickel-based catalyst according to any one of claims 1 to 3.

15. The method for deoxygenating olefins according to claim 14, wherein: The pressure of the deoxidation reaction is 0.1-0.3 MPa.

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