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CN-122006749-A - Acetylene selective hydrogenation catalyst based on metal-carrier strong interaction regulation and control as well as preparation method and application thereof

CN122006749ACN 122006749 ACN122006749 ACN 122006749ACN-122006749-A

Abstract

The invention discloses an acetylene selective hydrogenation catalyst based on strong interaction regulation and control of a metal-carrier, a preparation method and application thereof, wherein the catalyst comprises a carrier and an active component loaded on the carrier, the carrier is iron oxide doped with alkali metal and/or alkaline earth metal, the active component is palladium, and the load of the palladium is 0.01% -10% of the mass of the catalyst based on the total mass of the catalyst. The palladium catalyst has the advantages of lower metal palladium loading and higher metal atom utilization rate, and the iron oxide carrier doped with alkali metal and/or alkaline earth metal has reducibility, is easy to form metal-carrier strong interaction, is applied to acetylene selective hydrogenation reaction, can efficiently catalyze acetylene to selectively generate ethylene under milder conditions, has the advantages of high activity, high selectivity and stable catalysis, and has good application prospect, and the preparation process is simple and convenient and easy to amplify.

Inventors

  • GUO YALIN
  • Fu Baihong
  • HUANG JIANFENG

Assignees

  • 重庆大学

Dates

Publication Date
20260512
Application Date
20260327

Claims (10)

  1. 1. The acetylene selective hydrogenation catalyst based on metal-carrier strong interaction regulation is characterized by comprising a carrier and an active component loaded on the carrier; wherein the carrier is ferric oxide doped with alkali metal and/or alkaline earth metal, and the active component is palladium; Taking the total mass of the catalyst as a reference, the load of palladium is 0.01% -10% of the mass of the catalyst; And taking the total mass of the carrier as a reference, wherein the loading amount of the alkali metal and/or alkaline earth metal is 1% -20% of the mass of the carrier.
  2. 2. The acetylene selective hydrogenation catalyst based on the regulation of metal-support strong interaction according to claim 1, wherein the alkali metal-and/or alkaline earth metal-doped iron oxide is selected from at least one of sodium-doped iron oxide, potassium-doped iron oxide, magnesium-doped iron oxide and calcium-doped iron oxide, and the palladium is dispersed on the support in at least one of nano-particles, nanoclusters and atomic scale form.
  3. 3. The acetylene selective hydrogenation catalyst based on strong interaction regulation and control of metal-carrier according to claim 1, wherein the particle size of the alkali metal and/or alkaline earth metal doped iron oxide is 10 nm-5000 nm, and the specific surface area of the alkali metal and/or alkaline earth metal doped iron oxide is 15m 2 /g~300m 2 /g; the particle size of the palladium is 0.3 nm-100 nm.
  4. 4. A method for preparing the acetylene selective hydrogenation catalyst based on metal-support strong interaction regulation according to any one of claims 1 to 3, comprising the steps of: s1, preparing iron oxide doped with alkali metal and/or alkaline earth metal; s2, dissolving a palladium metal precursor in a solvent to obtain a mixed solution; S3, adding the iron oxide doped with the alkali metal and/or the alkaline earth metal into the mixed solution, and sequentially dispersing, filtering, washing and drying to obtain a catalyst precursor; And S4, roasting the catalyst precursor in an air atmosphere to obtain the catalyst.
  5. 5. The method according to claim 4, wherein in the step S1, the method for preparing the alkali metal and/or alkaline earth metal doped iron oxide comprises the steps of preparing the alkali metal and/or alkaline earth metal doped iron oxide through roasting by a precipitation deposition method, wherein the roasting temperature is 100-1000 ℃, and the roasting time is 1-48 h.
  6. 6. The method according to claim 4, wherein in step S2, the palladium metal precursor includes one or more of sodium tetrachloropalladate, palladium acetylacetonate, palladium chloride, tetraaminopalladium nitrate, palladium nitrate, and palladium acetate; the solvent is water or benzene; The concentration of the palladium metal precursor in the mixed solution is 0.1% -15%.
  7. 7. The preparation method according to claim 4, wherein in the step S3, the drying temperature is 40-300 ℃, and the drying time is 1-48 hours; In the step S4, the roasting temperature is 100-1000 ℃, and the roasting time is 1-48 hours.
  8. 8. Use of the catalyst for selective hydrogenation of acetylene based on regulation of strong metal-carrier interaction according to any one of claims 1 to 3 or the catalyst prepared by the preparation method according to any one of claims 4 to 7 in the preparation of ethylene by selective hydrogenation of acetylene.
  9. 9. The use according to claim 8, wherein the catalyst is subjected to a reduction treatment before application, the reduction treatment is performed under hydrogen gas with a concentration of 1% -100%, the temperature of the reduction treatment is 100 ℃ -900 ℃, and the time of the reduction treatment is 1-24 hours.
  10. 10. The application of the catalyst according to claim 8, wherein the reaction condition for preparing ethylene by the selective hydrogenation of acetylene comprises the reaction temperature of 20-500 ℃, the reaction pressure of 0.1-5 MPa and the inert gas with the volume fraction of 1-40% as an internal standard in the reaction gas.

Description

Acetylene selective hydrogenation catalyst based on metal-carrier strong interaction regulation and control as well as preparation method and application thereof Technical Field The invention relates to the technical field of selective hydrogenation of acetylene, in particular to an acetylene selective hydrogenation catalyst based on metal-carrier strong interaction regulation and control, and a preparation method and application thereof. Background Ethylene is a core role in the petrochemical industry, and is an important raw material for producing various plastics and a key index for measuring the national chemical industry level. However, in the production of ethylene by pyrolysis of petroleum hydrocarbons, a small amount of acetylene is inevitably mixed therein. Acetylene, although low in content, is extremely destructive, not only can it easily cause reactor fly temperatures, but also can poison and disable catalysts in subsequent polyethylene production processes. Therefore, the industry generally needs to strictly control the acetylene content in ethylene to be less than five parts per million (5 ppm) to ensure smooth production. In order to remove the acetylene, a plurality of selective hydrogenation catalysts are developed at home and abroad. Such catalysts include metals of group VIII (e.g., palladium, platinum, nickel, cobalt, iron) or group IB (e.g., copper, gold). Among them, palladium (Pd) has been a hot spot for research and application because of its excellent hydrogenation activity. However, due to the high activity of Pd, it is likely that ethylene will continue to hydrogenate to ethane during the reaction, even causing polymerization of the low carbon compounds to produce the byproduct "green oil", resulting in a decrease in the final ethylene selectivity. Therefore, researchers think that by separating the spacing between Pd atoms in an "isolated" way, such as by forming a monoatomic catalyst, side reactions can be effectively inhibited, and the selectivity to ethylene can be greatly improved. However, this concept is not easy to implement and requires precise control of synthesis conditions, which both test the technique and increase the cost. In addition, it is often difficult to achieve both the economy and the reactivity of the catalyst while seeking an extremely selective catalyst. The metal-support strong interaction (SMSI) was a platinum group metal (Pt, pd, ru, rh, ir, os) catalyst supported by Tauster et al in the study of TiO 2, and the adsorption of H 2 and CO molecules by the catalyst was found to decrease drastically or even approach zero after high temperature reduction treatment at 500 ℃. Meanwhile, when the SMSI effect occurs, besides the change of the adsorption capacity, the sample also has the characteristics that the metal particles are wrapped by the carrier, the electrons between the metal and the carrier are transferred, and the three characteristics are completely reversible after being treated by the oxidizing atmosphere. The existing state of the metal in the SMSI effect is generally in a particle state, and the SMSI effect can also occur for the metal existing in the monoatomic state, but at this time, an extremely high processing temperature is required, for example, when the SMSI effect occurs on the Pt monoatoms in the Pt 1-CeO2, the processing needs to be performed at 600 ℃, at this time, the processing temperature is too high, so that the monoatoms are highly likely to be agglomerated and deactivated, and the conversion rate and selectivity of the subsequent reaction are affected, so that the temperature for reducing the occurrence of the SMSI effect is a problem to be solved. Disclosure of Invention The invention aims to overcome the defects in the prior art and provide an acetylene selective hydrogenation catalyst based on strong interaction regulation and control of a metal-carrier, a preparation method and application thereof, wherein the catalyst has lower metal palladium loading capacity and higher metal atom utilization rate; the iron oxide carrier doped with alkali metal and/or alkaline earth metal has the advantages of reducibility, easiness in forming metal-carrier strong interaction, capability of catalyzing acetylene to generate ethylene at high efficiency under medium-low temperature conditions, high activity, high selectivity and stability in catalysis, simple and convenient preparation process, easiness in amplification and good application prospect, and is applied to acetylene selective hydrogenation reaction. In order to achieve the above purpose, the technical scheme of the invention is as follows: The acetylene selective hydrogenation catalyst based on metal-carrier strong interaction regulation comprises a carrier and an active component loaded on the carrier, wherein the carrier is iron oxide doped with alkali metal and/or alkaline earth metal, the active component is palladium, the loading of the palladium is 0.01% -10% of the catalys