K7[MnV13O38]·18H2Application of O as catalyst in aromatic hydrocarbon hydroxylation reaction
阅读说明：本技术 K7[MnV13O38]·18H2O作为催化剂在芳烃羟基化反应中的应用 (K7[MnV13O38]·18H2Application of O as catalyst in aromatic hydrocarbon hydroxylation reaction ) 是由 杨汉培 彭思佳 沈筱琦 于 2021-09-02 设计创作，主要内容包括：本发明公开了K-(7)[MnV-(13)O-(38)]·18H-(2)O作为催化剂在芳烃羟基化反应中的应用。本发明克服了现有羟基苯甲醚清洁化生产(双氧水和苯甲醚为原料一步制备对羟基苯甲醚)时存在的催化剂催化活性低导致的产物转化率低、产率低的问题,本发明选用K-(7)[MnV-(13)O-(38)]·18H-(2)O作为芳烃羟基化反应的催化剂,能够显著提高羟基化反应中苯甲醚的转化率和产物(对羟基苯甲醚)的产率,从而有效推进了对羟基苯甲醚的清洁化生产。(The invention discloses K 7 [MnV 13 O 38 ]·18H 2 The application of O as a catalyst in the hydroxylation reaction of aromatic hydrocarbon. The invention overcomes the problems of low product conversion rate and low yield caused by low catalytic activity of the catalyst in the existing clean production of hydroxyanisole (the method for preparing the hydroxyanisole by using hydrogen peroxide and anisole as raw materials in one step) 7 [MnV 13 O 38 ]·18H 2 The O is used as a catalyst for the hydroxylation reaction of the aromatic hydrocarbon, and can obviously improve the conversion rate of anisole and the yield of a product (p-hydroxyanisole) in the hydroxylation reaction, thereby effectively promoting the clean production of the p-hydroxyanisole.)
1.K7[MnV13O38]·18H2The application of O as a catalyst in the hydroxylation reaction of aromatic hydrocarbon.
2. K according to claim 17[MnV13O38]·18H2The application of O as a catalyst in the hydroxylation reaction of aromatic hydrocarbon is characterized in that: the aromatic hydrocarbon hydroxylation reaction comprises one of anisole hydroxylation reaction, chlorobenzene hydroxylation reaction or benzonitrile hydroxylation reaction.
3. K according to claim 27[MnV13O38]·18H2The application of O as a catalyst in the hydroxylation reaction of aromatic hydrocarbon is characterized in that: the hydroxylation reaction of the anisole is that the anisole and hydrogen peroxide are in K7[MnV13O38]·18H2O catalyzes the next step to produce p-hydroxyanisole.
4. K according to claim 17[MnV13O38]·18H2The application of O as a catalyst in the hydroxylation reaction of aromatic hydrocarbon is characterized in that K is7[MnV13O38]·18H2The preparation method of O comprises the following steps:
(1) adding potassium metavanadate into hot water, and adding sulfuric acid, manganese sulfate and potassium persulfate into the hot water; stirring is continued at elevated temperature until the solution evaporates to 1/3, which is no more than the volume of the original mixed solution, and precipitation is observed;
(2) filtering the reaction solution, adding potassium acetate into the filtrate, and standing overnight;
(3) taking out crystals generated in the solution after standing, washing with ethanol, and putting the solid in a mixed solution of potassium acetate and acetic acid for recrystallization under the conditions of heating and stirring after washing;
(4) after recrystallization, the solid is washed by ethanol solution, and then is dispersed in ethanol solution after washing, and is dried under air to obtain K7[MnV13O38]·18H2O。
5. K according to claim 47[MnV13O38]·18H2The application of O as a catalyst in the hydroxylation reaction of aromatic hydrocarbon is characterized in that: in the step (1), the reaction temperature is not higher than 70 ℃.
6. K according to claim 47[MnV13O38]·18H2The application of O as a catalyst in the hydroxylation reaction of aromatic hydrocarbon is characterized in that: in the step (1), the mixing mass ratio of potassium metavanadate, sulfuric acid, manganese sulfate and potassium persulfate is 13: 1: 1: 2.
7. k according to claim 47[MnV13O38]·18H2The application of O as a catalyst in the hydroxylation reaction of aromatic hydrocarbon is characterized in that: in the step (2), potassium acetate is added until the pH value of the solution is 3.8.
8. K according to claim 47[MnV13O38]·18H2The application of O as a catalyst in the hydroxylation reaction of aromatic hydrocarbon is characterized in that: in the step (3), the heating temperature for recrystallization does not exceed 120 ℃.
Technical Field
The invention relates to K7[MnV13O38]·18H2The application of O as a catalyst in the hydroxylation reaction of aromatic hydrocarbon.
Background
Under the trend of strongly advocating green development, the problems of multiple steps, multiple byproducts, high pollution, high toxicity and the like existing in the existing preparation process of p-hydroxyanisole need to be solved urgently. The existing research shows that the p-hydroxyanisole can be prepared in one step by taking hydrogen peroxide and anisole as raw materials (the hydrogen peroxide is taken as an oxidant to enable anisole to undergo one-step hydroxylation reaction), so that the reaction steps are greatly reduced, the operation is simple, the reaction condition is mild, no harmful by-product is generated, the method is an excellent environment-friendly preparation process, and the method has wide application prospect. Hydrogen peroxide (hydrogen peroxide) is a faintly acid colorless odorless transparent liquid, and needs to be oxidized under the action of a catalyst to obtain a target oxidation product, but the existing hydroxylation reaction catalyst is still insufficient for large-scale popularization due to low conversion rate.
Disclosure of Invention
The purpose of the invention is as follows: the invention aims to provide a catalyst K with high catalytic activity in an aromatic hydrocarbon hydroxylation reaction7[MnV13O38]·18H2O。
The technical scheme is as follows: k according to the invention7[MnV13O38]·18H2The application of O as a catalyst in the hydroxylation reaction of aromatic hydrocarbon.
Wherein, the aromatic hydrocarbon hydroxylation reaction comprises one of anisole hydroxylation reaction, chlorobenzene hydroxylation reaction or benzonitrile hydroxylation reaction.
The hydroxylation reaction of the anisole is that the anisole and hydrogen peroxide are in K7[MnV13O38]·18H2O catalyzes the next step to produce p-hydroxyanisole.
Wherein, K is7[MnV13O38]·18H2The preparation method of O specifically comprises the following steps:
(1) adding potassium metavanadate into hot water, and adding sulfuric acid, manganese sulfate and potassium persulfate into the hot water; stirring is continued at elevated temperature until the solution evaporates to 1/3, which is no more than the volume of the original mixed solution, and precipitation is observed;
(2) filtering the reaction solution, adding potassium acetate into the filtrate, and standing overnight;
(3) taking out crystals generated in the solution after standing, washing with ethanol, and putting the solid in a mixed solution of potassium acetate and acetic acid for recrystallization under the conditions of heating and stirring after washing;
(4) after recrystallization, the solid is washed by ethanol solution, and then is dispersed in ethanol solution with the mass fraction of 95 percent after being washed, and is dried under air to obtain K7[MnV13O38]·18H2O。K7[MnV13O38]·18H2O is black glossy powder.
Wherein, in the step (1), the reaction temperature is not higher than 70 ℃.
In the step (1), the mixing mass ratio of potassium metavanadate, sulfuric acid, manganese sulfate and potassium persulfate is 13: 1: 1: 2. orange crystals were obtained when the mass ratio of Mn: V was 1:13, golden yellow crystals were obtained when the mass ratio of Mn: V was 1:4, and a mixture of these products was obtained when the mass ratio of Mn: V was 1: 6.
Wherein, in the step (2), potassium acetate is added until the pH value of the solution is 3.8. In the solution, the manganate is most stable within a pH range of 3-6; at a pH close to 2, K7[MnV13O38]·18H2O will be converted into a dark red complex at pH>At 6 time, K7[MnV13O38]·18H2O will decompose. Effectively increases K when the pH is about 3.87[MnV13O38]·18H2The yield of O.
Wherein, in the step (3), the heating temperature for recrystallization does not exceed 120 ℃.
K7[MnV13O38]·18H2O has high catalytic activity and selectivity to hydroxylation reaction of aromatic hydrocarbon containing electron-withdrawing group, so that H2O2One oxygen atom in (A) is selected from H2O2Transfer to anisole to form p-hydroxyanisole.
Has the advantages that: compared with the prior art, the invention has the remarkable advantages that: the invention solves the problems of low product conversion rate and low yield caused by low catalytic activity of the catalyst in the existing clean production of hydroxyanisole (the method for preparing the hydroxyanisole by using hydrogen peroxide and anisole as raw materials in one step)7[MnV13O38]·18H2The O is used as a catalyst for the hydroxylation reaction of the aromatic hydrocarbon, can obviously improve the conversion rate of anisole and the yield of a product (p-hydroxyanisole) in the hydroxylation reaction, and also improves the selectivity of the anisole, thereby effectively promoting the clean production of the p-hydroxyanisole.
Drawings
FIG. 1 is K7[MnV13O38]·18H2A process flow diagram of a method of preparing O;
FIG. 2 is K7[MnV13O38]·18H2VO in O6Schematic structural diagram of (1).
Detailed Description
Example 1
Invention K7[MnV13O38]·18H2The preparation method of O comprises the following steps: adding 500mL of distilled water into a magnetic stirrer, adjusting the temperature, checking by using a thermometer, controlling the temperature of the water to be 70 ℃, sequentially adding 0.13mol of potassium metavanadate, 10mL of 1.0F sulfuric acid, 10mL of 1.0F manganese sulfate and 20mmol of potassium persulfate into the water, and keeping stirring; keeping the water temperature at 70 deg.C, stirring for 2.5-3.5h, evaporating to obtain a solution with a volume of about 150ml, and observing brown precipitate; filtering the obtained filtrate with a funnel, adding 18mL of 1F potassium acetate into the filtrate, adjusting the pH value of the solution to 3.8, and standing overnight; taking out the solid in the solution after standing overnight by using a suction filtration device, installing the filtration device, putting the solid on filter paper, washing by using a small amount (a few drops) of ethanol, and repeating the washing step after the liquid naturally flows down; after washing, preparing a round-bottom flask, and putting a mixed solution of washed solid and 0.5F potassium acetate and 0.5F acetic acid, wherein the adding amount of the mixed solution is that the solution is immersed in the solid; putting the round-bottom flask into a magnetic stirrer, heating to a temperature not exceeding 120 ℃, and after the solid is completely dissolved, closing the magnetic stirrer, naturally cooling the magnetic stirrer, and separating out orange-red crystals; carrying out suction filtration by using a cloth type funnel, adding a mixed solution of 0.5F potassium acetate and 0.5F acetic acid into the bottle again, wherein the adding amount of the mixed solution is that the solution is immersed into the solid, and carrying out recrystallization operation again; after recrystallization, carrying out suction filtration again, and taking out solids; placing the solid after suction filtration in a funnel deviceCleaning with 95% ethanol solution, and repeating for 2 times when the solution is naturally left after the solution is overflowed through the solid; and finally, dispersing the solid in an ethanol solution with the mass fraction of 95%, and drying in the air. Placing the obtained solid into a brown bottle, and identifying the shape and crystallization habit of the obtained K through a microscope and X-ray powder7[MnV13O38]The yield was 79%.
Example 2
Invention K7[MnV13O38]·18H2The preparation method of O comprises the following steps: adding 500mL of distilled water into a magnetic stirrer, adjusting the temperature, checking by using a thermometer, controlling the temperature of the water to be 70 ℃, sequentially adding 0.13mol of potassium metavanadate, 10mL of 1.0F sulfuric acid, 10mL of 1.0F manganese sulfate and 20mmol of potassium persulfate into the water, and keeping stirring; keeping the water temperature at 70 deg.C, stirring for 2.5-3.5h, evaporating to obtain a solution with a volume of about 150ml, and observing brown precipitate; filtering the obtained filtrate with a funnel, adding 18mL of 1F potassium acetate into the filtrate, adjusting the pH value of the solution to 3.8, and standing overnight; taking out the solid in the solution after standing overnight by using a suction filtration device, installing the filtration device, putting the solid on filter paper, washing by using a small amount (a few drops) of ethanol, and repeating the washing step after the liquid naturally flows down; after washing, preparing a round-bottom flask, and putting a mixed solution of washed solid and 0.5F potassium acetate and 0.5F acetic acid, wherein the adding amount of the mixed solution is that the solution is immersed in the solid; putting the round-bottom flask into a magnetic stirrer, heating to a temperature not exceeding 120 ℃, and after the solid is completely dissolved, closing the magnetic stirrer, naturally cooling the magnetic stirrer, and separating out orange-red crystals; carrying out suction filtration by using a cloth type funnel, adding a mixed solution of 0.5F potassium acetate and 0.5F acetic acid into the bottle again, wherein the adding amount of the mixed solution is that the solution is immersed into the solid, and carrying out recrystallization operation again; after recrystallization, carrying out suction filtration again, and taking out solids; placing the filtered solid in a funnel device, cleaning the solid by using an ethanol solution with the mass fraction of 95%, and repeating for 2 times when the solution is naturally left after the solid is soaked by the solution; and finally, dispersing the solid in an ethanol solution with the mass fraction of 95%, and drying in the air. Placing the solid in a brown bottle, and passing through a microscopeAnd characterization of X-ray powder morphology and crystal habit, the resulting K7[MnV13O38]The yield was 34%.
The catalysts K obtained in example 1 and example 27[MnV13O38]·18H2The conversion of anisole was determined by gas chromatography for O and the yields of hydroxylated product were 76% (98% selectivity) and 73% (96% selectivity), respectively.
The organic compounds were analyzed by gas chromatography using Agilent 1790 gas chromatography (GC-wax capillary 25m column). Column temperature 160 deg.C, gasification chamber temperature 250 deg.C, detector temperature 280 deg.C, nitrogen flow 1.0 ml/min-1The carrier gas flow rate was 30 ml/min.