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CN-121988404-A - Method for recycling acidic ionic liquid catalyst

CN121988404ACN 121988404 ACN121988404 ACN 121988404ACN-121988404-A

Abstract

The application discloses a method for recycling an acidic ionic liquid catalyst, and relates to the field of organic synthesis. Aiming at the problem of ion liquid deactivation caused by acid-soluble oil (ASO) accumulation in a carbon tetraalkylation reaction, the application provides a combined regeneration method of catalytic hydrogenation-solvent extraction-active component supplementation, wherein the complex structure of ASO and [ Al 2 Cl 7 ] − ] is destroyed through catalytic hydrogenation, and the ASO removal rate is obviously improved by combining solvent extraction and active component supplementation, so that the Bronsted acid and Lewis acidity of the ion liquid are comprehensively recovered. The method has the advantages of high regeneration efficiency, low cost and simple process, is suitable for industrial continuous operation, and has good popularization and application prospects.

Inventors

  • WANG RUIFENG
  • LI YU
  • WANG YUEMEI
  • ZHANG YANAN

Assignees

  • 鄂尔多斯应用技术学院

Dates

Publication Date
20260508
Application Date
20260410

Claims (8)

  1. 1. The method for recycling the acidic ionic liquid catalyst is characterized by comprising the following steps of: (1) The pretreatment extraction, namely mixing the acidic ionic liquid deactivated by accumulation of acid-soluble oil with an inert organic solvent, stirring and extracting, standing and layering, and separating a solvent phase containing part of free acid-soluble oil to obtain a pretreated ionic liquid phase; (2) Adding a hydrogenation catalyst into the pretreated ionic liquid phase obtained in the step (1), introducing hydrogen, and carrying out catalytic hydrogenation under the conditions of a reaction temperature of 80-120 ℃ and a reaction pressure of 1-3 MPa for 1-8 hours to enable unsaturated carbon-carbon double bonds in acid-soluble oil to be saturated in a hydrogenation way and destroy a complex structure formed by the unsaturated carbon-carbon double bonds and active anions of the ionic liquid; (3) Deep separation, namely filtering or settling to separate the hydrogenation catalyst after the reaction in the step (2), standing for layering, and separating out a solvent phase containing saturated hydrocarbon to obtain a regenerated ionic liquid phase; (4) And (3) supplementing an active component, namely supplementing a Lewis acid component and a Bronsted acid component into the regenerated ionic liquid phase obtained in the step (3), and regulating the acidity and catalytic activity of the ionic liquid to obtain the recyclable regenerated ionic liquid catalyst.
  2. 2. The method for recycling and regenerating an acidic ionic liquid catalyst according to claim 1, wherein the acidic ionic liquid in the step (1) is an chloroaluminate ionic liquid with a structural formula of [ R 3 NH]Cl-xAlCl 3 or [ R 3 NH]Cl-xAlCl 3 -yMCl n ], wherein M is one or more of transition metals of Cu, fe, ni, co, x=1.5 or 2.5, and y=1.1 or 1.0.
  3. 3. The method for recycling and regenerating an acidic ionic liquid catalyst according to claim 1, wherein in the step (1), the inert organic solvent is one or more of n-butane, n-hexane, cyclohexane and n-heptane, and the volume ratio of the solvent to the deactivated ionic liquid is 0.2-2:1.
  4. 4. The method for recycling and regenerating an acidic ionic liquid catalyst according to claim 1, wherein the hydrogenation catalyst in the step (2) is a supported catalyst, the active component is one or more selected from Pd, pt, rh, ni, and the carrier includes but is not limited to porous Al 2 O 3 、SiO 2 , activated carbon and molecular sieve.
  5. 5. The method for recycling and regenerating the acidic ionic liquid catalyst according to claim 4, wherein the loading amount of the active components in the hydrogenation catalyst is 0.5-10wt% and the catalyst consumption is 0.5-10wt% of the mass of the deactivated ionic liquid.
  6. 6. The method for recycling and regenerating an acidic ionic liquid catalyst according to claim 1, wherein the reaction temperature of the catalytic hydrogenation reaction in the step (2) is 80-120 ℃, the reaction pressure is 1.0-3.0 MPa, and the reaction time is 1-8 h.
  7. 7. The method for recycling and regenerating the acidic ionic liquid catalyst according to claim 1, wherein in the step (4), the acidic component of the Lewis acid is AlCl 3 and/or CuCl, the complementary amount of the acidic component is 1% -15% of the mass of the regenerated ionic liquid, the acidic component of the Br nsted acid is hydrogen chloride or tertiary butyl chloride, the hydrogen chloride is introduced into the regenerated ionic liquid to be saturated, and the addition amount of the tertiary butyl chloride is 0.5% -5% of the mass of the regenerated ionic liquid.
  8. 8. The method for recovering and regenerating an acidic ionic liquid catalyst according to claim 1, further comprising the step of pre-treating the carbon tetraalkylating raw material by adsorption dehydration or oxygen-containing compound removal to slow down the deactivation rate of the ionic liquid.

Description

Method for recycling acidic ionic liquid catalyst Technical Field The invention relates to the field of catalysts, in particular to a method for recycling an acidic ionic liquid catalyst. Background The carbon tetraalkylating oil has the advantages of high octane number, low saturated vapor pressure, low sulfur content, almost no olefin, aromatic hydrocarbon and the like, is an ideal blending component of the motor gasoline, and the acidic ionic liquid catalyst is widely applied to the carbon tetraalkylating reaction due to the environment-friendly and adjustable physical and chemical properties and excellent catalytic performance, and is used for producing the high-quality gasoline blending component with high octane number, low sulfur and low olefin content. However, in the continuous operation process of a long period, the catalytic activity of the ionic liquid catalyst is gradually reduced, and researches show that the deactivation is mainly caused by the central loss of Bronsted acid and the central loss of Lewis acid, and the existing regeneration method comprises supplementing active components such as HCl, alCl 3, cuCl and the like, or adopting means such as solvent extraction, electrolysis, silane reduction, metal reduction, catalytic hydrogenation and the like to remove ASO, but the problems of low ASO removal rate, high regeneration cost, complex process flow, increased ionic liquid circulation quantity and the like exist in the methods, so the application introduces a high-efficiency, economic and industrialized ionic liquid regeneration method. Disclosure of Invention The invention aims to provide a method for recycling an acidic ionic liquid catalyst, which aims to solve the problems in the prior art. A method for recycling and regenerating an acidic ionic liquid catalyst, which comprises the following steps: (1) The pretreatment extraction, namely mixing the acidic ionic liquid deactivated by accumulation of acid-soluble oil with an inert organic solvent, stirring and extracting, standing and layering, and separating a solvent phase containing part of free acid-soluble oil to obtain a pretreated ionic liquid phase; (2) Adding a hydrogenation catalyst into the pretreated ionic liquid phase obtained in the step (1), introducing hydrogen, and carrying out catalytic hydrogenation under the conditions of a reaction temperature of 80-120 ℃ and a reaction pressure of 1-3 MPa for 1-8 hours to enable unsaturated carbon-carbon double bonds in acid-soluble oil to be saturated in a hydrogenation way and destroy a complex structure formed by the unsaturated carbon-carbon double bonds and active anions of the ionic liquid; (3) Deep separation, namely filtering or settling to separate the hydrogenation catalyst after the reaction in the step (2), standing for layering, and separating out a solvent phase containing saturated hydrocarbon to obtain a regenerated ionic liquid phase; (4) And (3) supplementing an active component, namely supplementing a Lewis acid component and a Bronsted acid component into the regenerated ionic liquid phase obtained in the step (3), and regulating the acidity and catalytic activity of the ionic liquid to obtain the recyclable regenerated ionic liquid catalyst. As an optimization, the acidic ionic liquid in the step (1) is chloroaluminate ionic liquid, and the structural general formula of the acidic ionic liquid is [ R 3NH]Cl-xAlCl3 or [ R 3NH]Cl-xAlCl3-yMCln ], wherein M is one or more of Cu, fe, ni, co, x=1.5 or 2.5, and y=1.1 or 1.0. As optimization, the inert organic solvent in the step (1) is one or more of n-butane, n-hexane, cyclohexane and n-heptane, and the volume ratio of the solvent to the deactivated ionic liquid is 0.2-2:1. Preferably, the hydrogenation catalyst in the step (2) is a supported catalyst, the active component is one or more selected from Pd, pt, rh, ni, and the carrier comprises but is not limited to porous Al 2O3、SiO2, activated carbon and molecular sieve. As optimization, the loading amount of the active components in the hydrogenation catalyst is 0.5-10wt%, and the dosage of the catalyst is 0.5-10wt% of the mass of the deactivated ionic liquid. As optimization, the reaction temperature of the catalytic hydrogenation reaction in the step (2) is 80-120 ℃, the reaction pressure is 1.0-3.0 mpa, and the reaction time is 1-8 h. As optimization, the acidic components of the Lewis acid in the step (4) are AlCl 3 and/or CuCl, the supplementing amount of the acidic components is 1-15% of the mass of the regenerated ionic liquid, the acidic components of the Bronsted acid are hydrogen chloride or tertiary butyl chloride, the hydrogen chloride is introduced into the regenerated ionic liquid to be saturated, and the adding amount of the tertiary butyl chloride is 0.5-5% of the mass of the regenerated ionic liquid. Preferably, the method further comprises pre-treating the carbon tetraalkylating feedstock with adsorption dehydration or oxygenate removal to slow t