Method for preparing imidazole acetate ionic liquid

Abstract

The invention discloses a method for preparing imidazole acetate ionic liquid, which comprises the following steps of: mixing organic alcoholic solution of imidazole halid salt and organic alcoholic solution of acetate, and reacting at preset temperature; evaporating to remove partial organic alcohol in a reaction system in the reaction process; and filtering reaction mixed liquor and removing organic alcohol from filtrate to obtain the imidazole acetate ionic liquid. In the method for preparing the imidazole acetate ionic liquid, the partial organic alcohol is evaporated and removed in the reaction process, so distillation can be performed by means of reaction temperature, the load of evaporating and removing a solvent after filtration is reduced, the cost is reduced, the solvent amount in the filtrate is small, and the inorganic salt amount remained in the solvent is small; therefore, the purity of the imidazole acetate ionic liquid subjected to solvent evaporation and removal is improved.

Description

technical field

[0001] The invention relates to the field of ionic liquid preparation, in particular to a method for preparing imidazole acetate ionic liquid. Background technique

[0002] Ionic liquids are composed of anions and cations, which are a special form of ions. Due to its special properties such as non-volatile, non-flammable, high electrical conductivity, good thermal and chemical stability, strong polarity and its polarity can be adjusted according to the choice of anion and cation, and it is a good solvent for many substances, it is used in organic Synthesis, chemical separation, material preparation, electrochemistry and other fields have attracted much attention, and they are the new generation of media / materials that are most likely to replace heavily polluted catalysts and solvents.

[0003] The anion of the acetate ionic liquid is acetate, so in the application, the acetate ionic liquid can avoid problems such as corrosion, catalyst poisoning, and environ...

Examples

preparation example Construction

[0024] The preparation method of imidazole acetate ionic liquid provided by the invention may further comprise the steps:

[0025] The first step: mixing the organic alcohol solution of imidazole halide salt with the organic alcohol solution of acetate, and reacting at a predetermined temperature;

[0026] The "imidazole halide salt organic alcohol solution" referred to here refers to the imidazole halide salt organic alcohol solution formed by dissolving imidazole halide salt in organic alcohol. Preferably, the imidazole halide salt used in the present invention has a structural formula: Wherein, R is an alkyl group with 1 to 6 carbon atoms, an alkyl group containing an aromatic hydrocarbon ring, a halogen-substituted alkyl group or an allyl group, and X -is fluorine, chlorine, bromine or iodide ion. More preferably, R is ethyl or butyl and X- is chloride or bromide. The "acetate" used in the present invention refers to the acetate whose cation is an alkali metal cation, a...

Embodiment 1

[0037] Preparation of 1-ethyl-3-methylimidazolium acetate

[0038] After heating and melting 1-ethyl-3-methylimidazolium chloride salt, mix it with absolute ethanol at a mass ratio of 1:0.8 to form a 1-ethyl-3-methylimidazolium chloride absolute ethanol solution. Potassium acetate with an equimolar amount of 1-ethyl-3-methylimidazole chloride is dissolved in absolute ethanol to form a 60°C saturated solution of potassium acetate in absolute ethanol, and then 1-ethyl-3-methylimidazole The chloride salt absolute ethanol solution was slowly added to the stirred potassium acetate absolute ethanol solution at 60°C for reaction. Continuously distill off part ethanol in reaction process (the ethanol amount that steams off accounts for 65% of ethanol total amount in 1-ethyl-3-methylimidazolium chloride absolute ethanol solution and potassium acetate absolute ethanol solution), And gradually reduce the reaction temperature until room temperature. After the reaction was completed, the...

Embodiment 2

[0040] Preparation of 1-ethyl-3-methylimidazolium acetate

[0041] After heating and melting 1-ethyl-3-methylimidazolium bromide salt, mix it with absolute ethanol at a mass ratio of 1:1.0 to prepare 1-ethyl-3-methylimidazolium bromide salt absolute ethanol solution, and Potassium acetate with an equimolar amount of 1-ethyl-3-methylimidazolium bromide is dissolved in absolute ethanol to form a 75°C saturated solution of potassium acetate in absolute ethanol, and then 1-ethyl-3-methylimidazole The bromide salt absolute ethanol solution was slowly added to the stirred potassium acetate absolute ethanol solution at 75°C for reaction. Part ethanol is continuously distilled off in the reaction process (the ethanol amount steamed off accounts for 70% of the ethanol total amount in 1-ethyl-3-methylimidazolium bromide absolute ethanol solution and potassium acetate absolute ethanol solution), And gradually reduce the reaction temperature until room temperature. After the reaction wa...

technical field

[0001] The invention relates to the field of ionic liquid preparation, in particular to a method for preparing imidazole acetate ionic liquid. Background technique

[0002] Ionic liquids are composed of anions and cations, which are a special form of ions. Due to its special properties such as non-volatile, non-flammable, high electrical conductivity, good thermal and chemical stability, strong polarity and its polarity can be adjusted according to the choice of anion and cation, and it is a good solvent for many substances, it is used in organic Synthesis, chemical separation, material preparation, electrochemistry and other fields have attracted much attention, and they are the new generation of media / materials that are most likely to replace heavily polluted catalysts and solvents.

[0003] The anion of the acetate ionic liquid is acetate, so in the application, the acetate ionic liquid can avoid problems such as corrosion, catalyst poisoning, and environ...

Examples

preparation example Construction

[0024] The preparation method of imidazole acetate ionic liquid provided by the invention may further comprise the steps:

[0025] The first step: mixing the organic alcohol solution of imidazole halide salt with the organic alcohol solution of acetate, and reacting at a predetermined temperature;

[0026] The "imidazole halide salt organic alcohol solution" referred to here refers to the imidazole halide salt organic alcohol solution formed by dissolving imidazole halide salt in organic alcohol. Preferably, the imidazole halide salt used in the present invention has a structural formula: Wherein, R is an alkyl group with 1 to 6 carbon atoms, an alkyl group containing an aromatic hydrocarbon ring, a halogen-substituted alkyl group or an allyl group, and X -is fluorine, chlorine, bromine or iodide ion. More preferably, R is ethyl or butyl and X- is chloride or bromide. The "acetate" used in the present invention refers to the acetate whose cation is an alkali metal cation, a...

Embodiment 1

[0037] Preparation of 1-ethyl-3-methylimidazolium acetate

[0038] After heating and melting 1-ethyl-3-methylimidazolium chloride salt, mix it with absolute ethanol at a mass ratio of 1:0.8 to form a 1-ethyl-3-methylimidazolium chloride absolute ethanol solution. Potassium acetate with an equimolar amount of 1-ethyl-3-methylimidazole chloride is dissolved in absolute ethanol to form a 60°C saturated solution of potassium acetate in absolute ethanol, and then 1-ethyl-3-methylimidazole The chloride salt absolute ethanol solution was slowly added to the stirred potassium acetate absolute ethanol solution at 60°C for reaction. Continuously distill off part ethanol in reaction process (the ethanol amount that steams off accounts for 65% of ethanol total amount in 1-ethyl-3-methylimidazolium chloride absolute ethanol solution and potassium acetate absolute ethanol solution), And gradually reduce the reaction temperature until room temperature. After the reaction was completed, the...

Embodiment 2

[0040] Preparation of 1-ethyl-3-methylimidazolium acetate

[0041] After heating and melting 1-ethyl-3-methylimidazolium bromide salt, mix it with absolute ethanol at a mass ratio of 1:1.0 to prepare 1-ethyl-3-methylimidazolium bromide salt absolute ethanol solution, and Potassium acetate with an equimolar amount of 1-ethyl-3-methylimidazolium bromide is dissolved in absolute ethanol to form a 75°C saturated solution of potassium acetate in absolute ethanol, and then 1-ethyl-3-methylimidazole The bromide salt absolute ethanol solution was slowly added to the stirred potassium acetate absolute ethanol solution at 75°C for reaction. Part ethanol is continuously distilled off in the reaction process (the ethanol amount steamed off accounts for 70% of the ethanol total amount in 1-ethyl-3-methylimidazolium bromide absolute ethanol solution and potassium acetate absolute ethanol solution), And gradually reduce the reaction temperature until room temperature. After the reaction wa...