Catalyst composition and method for preparing peroxy acid

Abstract

The invention belongs to the technical field of chemical product production, and particularly relates to a catalyst composition and a method for preparing peroxy acid. The catalyst composition contains an acidic catalyst and a stabilizer, the stabilizer is a nitrogen-containing alkaline compound, and an N atom has lone pair electrons. When the specific catalyst composition is used for preparing peroxy acid, the conversion rate of hydrogen peroxide can be gt; the selectivity of the prepared peroxy acid is gt; 70%, and the finally obtained peroxy acid product is used for preparing caprolactone, so that the conversion rate of cyclohexanone is gt; the selectivity of the prepared caprolactone is gt; 95%.

Description

Technical Field

[0001] The invention relates to the technical field of chemical product production, and in particular to a catalyst composition and a method for preparing peroxy acid. Background Art

[0002] Peracid is an oxidant with excellent performance. It can be used as a highly effective disinfectant or sterilizer in daily life. It can also be used as a bleaching agent for the bleaching of textiles, paper, paraffin and oils. In industry, it is mainly used to oxidize cyclohexanone to produce caprolactone.

[0003] The reaction formula for peroxyacid synthesis is RCOOH+H 2 O 2 →RCOOOH+H 2 O, this reaction is a nucleophilic reaction. Due to the weak affinity of hydrogen peroxide, it is difficult to react with the carbonyl group of the organic acid, resulting in limited reaction kinetics and low reaction rate. In the production process of peroxyacid, heteropolyacids, nitric acid and sulfuric acid are usually used as catalysts to improve the reaction efficiency.

[0004] Since the peroxyacid synthesis reaction is a homogeneous reaction, the acid catalyst remains in the product solution and cannot be separated. The residual catalyst will affect the quality of the product peroxyacid. For example, when it is used to synthesize caprolactone, the residual protonic acid catalyst will promote the polycondensation of caprolactone, greatly reducing the selectivity of the reaction (Note: this is mainly peroxypropionic acid and peroxyacids with higher molecular weight. In fact, the boiling points of peroxyacids such as formic acid and peroxyacetic acid are relatively low. The peroxyacid can be extracted from the top of the tower by distillation, and the remaining catalyst can be extracted from the bottom of the tower). When the peroxyacid does not contain a strong acid catalyst, the selectivity for synthesizing caprolactone is higher. The reaction process is shown in formula (1). When the peroxyacid contains a strong acid catalyst, the selectivity for synthesizing caprolactone is lower. Caprolactone will generate various isomerization products and various oligomers such as dimers and trimers.

[0005]

[0006] Patent application CN1034500C discloses a method for synthesizing peroxypropionic acid using boric acid as a catalyst. Boric acid has a weak acidity, and the effect of bringing it downstream on the synthesis of caprolactone is also weak, and it will not produce too many side reactions, but the weak acidity of boric acid will limit the synthesis efficiency of peroxy acid. Patent application CN103570667A discloses a method for continuously preparing caprolactone, which uses boric acid as a catalyst and hydrogen peroxide as an oxidant to continuously oxidize organic carboxylic acids in multiple reaction distillation towers to obtain peroxy acid; then the peroxy acid and cyclohexanone are continuously introduced into multiple series stirred tanks for reaction to obtain a caprolactone solution. Boric acid is a weak acid that has little effect on the polymerization of caprolactone, but its catalytic peroxy acid synthesis efficiency is low, and multiple reaction distillation towers connected in series increase energy consumption, which is also not conducive to industrial production. Summary of the invention

[0007] The purpose of the present invention is to solve the problem that the peracid synthesis efficiency is low and the peracid raw material liquid usually has residual acid catalyst in the peracid oxidation process in the prior art, which leads to the problem that the peracid raw material liquid leads to low caprolactone selectivity and decreased yield when oxidizing cyclohexanone to prepare caprolactone, thereby providing a catalyst composition and a method for preparing peracid. An acid catalyst is added to the composition to promote the synthesis of peracid, and a specific alkaline stabilizer is also added to obtain a stable peracid product. Then, when the peracid is prepared by using the specific catalyst composition, the conversion rate of hydrogen peroxide can be greater than 95%, and the selectivity of the prepared peracid can be greater than 70%. The finally obtained peracid product is used to prepare caprolactone, so that the conversion rate of cyclohexanone is greater than 95%, and the selectivity of the prepared caprolactone is greater than 95%.

[0008] The first aspect of the present invention provides a catalyst composition, which contains an acidic catalyst and a stabilizer, and the acidic catalyst and the stabilizer are stored independently, wherein the stabilizer is a nitrogen-containing basic compound, and the N atom has a lone pair of electrons.

[0009] Preferably, the molar ratio of the stabilizer to the acidic catalyst is 1 to 30:1, more preferably 3 to 10:1.

[0010] Preferably, the stabilizer is selected from one or more of methylamine, ethylamine, triethylamine, trimethylamine, ethylenediamine, urea, ethanolamine, isopropylamine, tert-butylamine, aniline, benzylamine, cyclohexylamine, pyridine, lutidine, pyrrole, indole, acridine, carbazole and quinoline.

[0011] Preferably, the acidic catalyst is selected from one or more of sulfuric acid, nitric acid, heteropoly acid and isopoly acid. More preferably, the heteropoly acid is selected from one or more of phosphomolybdic acid, phosphotungstic acid and silicotungstic acid. Further preferably, the isopoly acid is selected from one or more of decatungstic acid, heptungstic acid, octamolybdic acid and dodecamolybdic acid.

[0012] A second aspect of the present invention provides a method for preparing peroxyacid, which is prepared using the peroxyacid composition described above, and the method comprises the following steps:

[0013] (1) mixing an organic solvent, an organic acid, hydrogen peroxide and an acidic catalyst to obtain a peracid synthesis solution;

[0014] (2) reacting the peroxyacid synthetic solution with a stabilizer;

[0015] The stabilizer is a nitrogen-containing basic compound, and the N atom has a lone pair of electrons.

[0016] Preferably, the molar ratio of the stabilizer to the acidic catalyst is 1 to 30:1, more preferably 3 to 10:1.

[0017] Preferably, the stabilizer is selected from one or more of methylamine, ethylamine, triethylamine, trimethylamine, ethylenediamine, urea, ethanolamine, isopropylamine, tert-butylamine, aniline, benzylamine, cyclohexylamine, pyridine, lutidine, pyrrole, indole, acridine, carbazole and quinoline.

[0018] Preferably, the acidic catalyst is selected from one or more of sulfuric acid, nitric acid, heteropoly acid and isopoly acid. More preferably, the heteropoly acid is selected from one or more of phosphomolybdic acid, phosphotungstic acid and silicotungstic acid. Further preferably, the isopoly acid is selected from one or more of decatungstic acid, heptungstic acid, octamolybdic acid and dodecamolybdic acid.

[0019] Preferably, based on the total weight of the organic solvent, organic acid, hydrogen peroxide and acidic catalyst as 100 weight %, the content of the organic solvent is 5 to 70 weight %, and the content of the organic acid is

[0020] The content of the organic solvent is 10-50% by weight, the content of the organic acid is 10-50% by weight, the content of the hydrogen peroxide is 10-60% by weight, and the content of the acidic catalyst is 0.05-10% by weight.

[0021] Preferably, the organic solvent is selected from one or more of ethyl acetate, propyl acetate, isobutyl acetate, propyl propionate, isopropyl propionate, ethyl propionate, butyl acetate, n-ethane, methylene chloride, dichloromethane, cyclohexane, benzene and acetonitrile.

[0022] Preferably, the organic acid is selected from one or more of formic acid, acetic acid, propionic acid and butyric acid.

[0023] Preferably, in step (1), the mixing conditions include: temperature of 0 to 130° C., time of 0.05 to 30 h, and absolute pressure of 0.001 to 1 MPa.

[0024] Preferably, the concentration of peracid in the peracid synthesis solution is 5 to 50% by weight.

[0025] Preferably, in step (2), the reaction conditions include: temperature of 10-50° C., time of 0.2-1.5 h, and absolute pressure of 0.1-0.3 MPa.

[0026] Preferably, the concentration of the hydrogen peroxide solution is 10 to 80% by weight, more preferably 25 to 50% by weight.

[0027] The catalyst composition of the present invention combines a specific catalyst with a specific stabilizer, and utilizes the principle that the catalyst and the stabilizer undergo a neutralization reaction or a complexation reaction. Then, according to the method of the present invention, the catalyst composition is applied to the process of preparing peroxyacid. First, a composition containing a specific organic solvent, an organic acid, hydrogen peroxide and an acidic catalyst is reacted under certain conditions to obtain a peroxyacid synthetic solution, and then the synthetic solution is further reacted with a specific stabilizer to eliminate H in the synthetic solution. + The concentration of hydrogen peroxide is increased to improve the quality and stability of the peracid product, so that the conversion rate of hydrogen peroxide is greater than 95%, and the selectivity of the prepared peracid is greater than 70%. The peracid is used to prepare caprolactone, so that the conversion rate of cyclohexanone is greater than 95%, and the selectivity of the prepared caprolactone is greater than 95%. DETAILED DESCRIPTION

[0028] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0029] The endpoints and any values ​​of the ranges disclosed in this article 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 endpoint values ​​of each range, the endpoint values ​​of each range and the 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 as specifically disclosed in this article.

[0030] The first aspect of the present invention provides a catalyst composition, which contains an acidic catalyst and a stabilizer, and the acidic catalyst and the stabilizer are stored independently, wherein the stabilizer is a nitrogen-containing basic compound, and the N atom has a lone pair of electrons.

[0031] In order to make the selectivity of the prepared peracid product greater than 70%, and use the peracid to prepare caprolactone, so that the conversion rate of cyclohexanone is greater than 95%, and the selectivity of the prepared caprolactone is greater than 95%, the amount of the stabilizer and the acid catalyst needs to be controlled within a certain range. In a specific embodiment, the molar ratio of the stabilizer to the acid catalyst is 1 to 30:1. In a preferred embodiment, the molar ratio of the stabilizer to the acid catalyst is 3 to 10:1, for example, 3:1, 4:1, 5:1, 6:1,

[0032] 1, 7:1, 8:1, 9:1 or 10:1.

[0033] In order to eliminate the residual acid solution in the peracid synthesis process and improve the stability and quality of the peracid product, in the composition of the present invention, in a specific embodiment, the stabilizer is selected from one or more of methylamine, ethylamine, triethylamine, trimethylamine, ethylenediamine, urea, ethanolamine, isopropylamine, tert-butylamine, aniline, benzylamine, cyclohexylamine, pyridine, lutidine, pyrrole, indole, acridine, carbazole and quinoline. In this article, the heterocyclics in the stabilizer include but are not limited to the heterocyclic compounds themselves introduced above, and may include substitutions in the form of various functional groups. In a preferred embodiment, the stabilizer is selected from one or more of pyridine, aniline, ethylamine, isopropylamine and ethanolamine.

[0034] In order to improve the synthesis efficiency of peroxyacid and optimize the quality and stability of peroxyacid products, in the composition of the present invention, in a specific embodiment, the acidic catalyst can be a catalyst that releases H + In a preferred embodiment, the acidic catalyst is selected from one or more of sulfuric acid, nitric acid, heteropoly acid and isopoly acid, and specifically, boric acid and / or metaboric acid are optionally added.

[0035] In the composition of the present invention, in a specific embodiment, the heteropoly acid and the isopoly acid can be conventionally selected in the art, and can include modified doping of elements. In this article, the heteropoly acid refers to a polyoxometalate formed by condensation of different types of oxygen-containing acid radical ions, and the isopoly acid refers to a metal oxometalate formed by condensation of the same type of oxygen-containing acid radical ions. In a preferred embodiment, the heteropoly acid is selected from one or more of phosphomolybdic acid, phosphotungstic acid and silicotungstic acid, and the isopoly acid is selected from one or more of decatungstic acid, heptungstic acid, octamolybdic acid and dodecamoylic acid.

[0036] A second aspect of the present invention provides a method for preparing peroxyacid, the method comprising the following steps:

[0037] (1) mixing an organic solvent, an organic acid, hydrogen peroxide and an acidic catalyst to obtain a peracid synthesis solution;

[0038] (2) reacting the peroxyacid synthetic solution with a stabilizer;

[0039] The stabilizer is a nitrogen-containing basic compound, and the N atom has a lone pair of electrons.

[0040] In the method of the present invention, in order to improve the quality and stability of the peroxy acid product, make the selectivity of the prepared peroxy acid greater than 70%, and use the peroxy acid to prepare caprolactone, make the conversion rate of cyclohexanone greater than 95%, and the prepared caprolactone selectivity greater than 95%, in a specific embodiment, the molar ratio of the stabilizer to the acid catalyst is 1 to 30: 1. In a preferred embodiment, the molar ratio of the stabilizer to the acid catalyst is 3 to 10: 1, for example, 3: 1, 4: 1, 5: 1, 6: 1, 7: 1, 8: 1, 9: 1 or 10: 1.

[0041] In order to improve the synthesis efficiency of peroxyacid and optimize the quality of peroxyacid products, in the method of the present invention, in a specific embodiment, the acidic catalyst can be a catalyst that releases H + In a preferred embodiment, the acidic catalyst is selected from one or more of sulfuric acid, nitric acid, heteropoly acid and isopoly acid, and specifically, boric acid and / or metaboric acid are optionally added.

[0042] In the method of the present invention, in a specific embodiment, the heteropoly acid and the isopoly acid can be conventionally selected in the art, and can include modified doping of elements. In a preferred embodiment, the heteropoly acid is selected from one or more of phosphomolybdic acid, phosphotungstic acid and silicotungstic acid. In a more preferred embodiment, the isopoly acid is selected from one or more of decatungstic acid, heptatungstic acid, octamolybdic acid and dodecamoylic acid.

[0043] In order to eliminate the residual acid solution in the peracid synthesis process and improve the stability and quality of the peracid product, in the method of the present invention, in a specific embodiment, the stabilizer is selected from one or more of methylamine, ethylamine, triethylamine, trimethylamine, ethylenediamine, urea, ethanolamine, isopropylamine, tert-butylamine, aniline, benzylamine, cyclohexylamine, pyridine, lutidine, pyrrole, indole, acridine, carbazole and quinoline. In a preferred embodiment, the stabilizer is selected from one or more of pyridine, aniline, ethylamine, isopropylamine and ethanolamine.

[0044] In order to improve the conversion rate of hydrogen peroxide in the peracid synthesis process and improve the quality of the peracid product, the dosage ratio of the organic solvent, organic acid, hydrogen peroxide and acidic catalyst should be controlled within a certain range. In the method of the present invention, in a specific embodiment, based on the total weight of the organic solvent, organic acid, hydrogen peroxide and acidic catalyst as 100 weight%, the content of the organic solvent is 5-70 weight%, the content of the organic acid is 5-70 weight%, the content of the hydrogen peroxide is 5-70 weight%, and the content of the acidic catalyst is 0.01-15 weight%.

[0045] In the method of the present invention, in a preferred embodiment, based on the total weight of the organic solvent, organic acid, hydrogen peroxide and acidic catalyst as 100 weight%, the content of the organic solvent is 10-50 weight%, the content of the organic acid is 10-50 weight%, the content of the hydrogen peroxide is 10-60 weight%, and the content of the acidic catalyst is 0.05-10 weight%.

[0046] In the method of the present invention, in order to form an azeotrope with water and form an oil-water two-phase solvent with water after cooling, so as to facilitate separation and recovery of the solvent, in a specific embodiment, the organic solvent is selected from one or more of ethyl acetate, propyl acetate, isobutyl acetate, propyl propionate, isopropyl propionate, ethyl propionate, butyl acetate, n-ethane, methylene chloride, dichlorohexane, cyclohexane, benzene and acetonitrile. In a preferred embodiment, the organic solvent is selected from one or more of dichlorohexane, ethyl propionate, cyclohexane and benzene.

[0047] In the method of the present invention, in a specific embodiment, as long as the organic acid is in liquid phase or soluble in a solvent, it can be an organic acid with a relatively high acid strength in the art. In a preferred embodiment, the organic acid is selected from one or more of formic acid, acetic acid, propionic acid and butyric acid.

[0048] In the method of the present invention, in a specific embodiment, the hydrogen peroxide is a conventional oxidizing solvent. In a preferred embodiment, the concentration of the hydrogen peroxide is 10 to 80% by weight. In a more preferred embodiment, the concentration of the hydrogen peroxide is 25 to 50% by weight, for example, 25%, 30%, 40% or 50% by weight.

[0049] In the method of the present invention, in a specific embodiment, in step (1), the organic solvent, organic acid, hydrogen peroxide and acidic catalyst can be introduced into the reactor separately and then mixed with other materials. In a preferred embodiment, the organic solvent, organic acid, hydrogen peroxide and acidic catalyst can be mixed in pairs and then mixed with other materials.

[0050] In the method of the present invention, in a specific embodiment, in step (1), the mixing conditions include: temperature of 0 to 130° C., reaction residence time of 0.05 to 30 h, and absolute pressure of 0.001 to 1 MPa.

[0051] In the method of the present invention, in a specific embodiment, in step (1), the reactor used in the method can be a microchannel reactor, a fixed bed reactor, a tank reactor, a reactive distillation column, a static mixing reactor or a membrane reactor. In a preferred embodiment, the reactor used in the method can be one of the reactors in the specific embodiment, or a combination of multiple reactors. In a more preferred embodiment, the reaction process in the reactor is intermittent or continuous.

[0052] In the method of the present invention, in a specific embodiment, in step (1), when the reactor used in the reaction is a microchannel reactor, a fixed bed reactor, a tank reactor, a reaction distillation tower, a static mixing reactor or a membrane reactor, in order to increase the reaction rate and avoid the decomposition of peracid and hydrogen peroxide, the reaction temperature is 35 to 80°C.

[0053] In the method of the present invention, in a specific embodiment, in step (1), when the reactor used in the reaction is a distillation tower or a reactive distillation tower, the temperature of the tower section containing hydrogen peroxide and peracid is 35 to 85°C.

[0054] In the method of the present invention, in a specific embodiment, in step (1), when the reactor used in the reaction is a microchannel reactor, a fixed bed reactor, a tank reactor or a static mixing reactor, the absolute pressure of the reaction is 0.01 to 1 MPa, preferably 0.05 to 0.5 MPa.

[0055] In the method of the present invention, in a specific embodiment, in step (1), when the reactor used in the reaction is a distillation tower or a reactive distillation tower, the absolute pressure of the reaction is 0.001 to 0.5 MPa, preferably 0.002 to 0.2 MPa.

[0056] In the method of the present invention, in a preferred embodiment, under the preferred material formulation and reaction conditions, the reaction residence time can also be controlled within a certain range, and the selectivity and efficiency of the prepared peroxy acid will be improved. In step (1), the reaction residence time is 0.1 to 10 hours.

[0057] In the method of the present invention, in a specific embodiment, in step (1), the concentration of peracid in the peracid synthesis solution is 5 to 50 weight %, for example, it can be 5 weight %, 10 weight %, 20 weight %, 30 weight %, 40 weight %, 45 weight % or 50 weight %.

[0058] In the method of the present invention, in a specific embodiment, in step (1), the peroxyacid synthetic solution can be an aqueous peroxyacid or an anhydrous peroxyacid. In this article, the aqueous peroxyacid refers to the water in the peroxyacid product that is not separated, and the water includes the water brought in by the raw material hydrogen peroxide, the water generated by the reaction, and the water added to adjust the concentration of the diluted product. The anhydrous peroxyacid refers to the water in the peroxyacid product that has been removed, and the removed water includes the water brought in by the hydrogen peroxide and the water generated by the reaction. There is no special requirement for the dehydration method, and the water can be removed by azeotropic reaction distillation, or by membrane separation or adsorption removal by adsorption material. The water content in the dehydrated product is less than 0.9% by weight.

[0059] In the method of the present invention, in a specific embodiment, in step (2), the reaction conditions include: temperature of -20 to 70°C, for example, -20°C, 0°C, 25°C, 30°C, 40°C, 50°C, 55°C, 60°C or 70°C; time of 0.1 to 10 h, for example, 0.1 h, 0.2 h, 0.5 h, 1 h, 2 h, 5 h or 10 h; absolute pressure of 0 to 0.5 MPa, for example, 0.1 MPa, 0.15 MPa, 0.2 MPa, 0.3 MPa, 0.4 MPa or 0.5 MPa.

[0060] In the method of the present invention, in a preferred embodiment, in step (2), the reaction conditions include: temperature of 0 to 70°C, time of 0.1 to 3 hours, and absolute pressure of 0.1 to 0.5 MPa. In a more preferred embodiment, in step (2), the reaction conditions include: temperature of 10 to 50°C, time of 0.2 to 1.5 hours, and absolute pressure of 0.1 to 0.3 MPa.

[0061] In the method of the present invention, in step (2), in a specific operation process, the stabilizer is added to the peracid synthesis solution under stirring conditions. Specifically, the stirring conditions include: a speed of 10 to 600 rpm and a time of 0.1 to 10 hours.

[0062] In the method of the present invention, during the specific operation, the peracid solution obtained in step (2) is stored at 0° C., and the daily decomposition rate of the peracid is less than 0.05%.

[0063] In the method of the present invention, in a specific embodiment, the pH value of the solution obtained by the reaction in step (2) is -1 to 3, for example, it can be -1, 0.1, 1, 2, 2.5 or 3.

[0064] In the method of the present invention, the peracid solution obtained in step (2) is reacted with cyclohexanone to prepare caprolactone. In the specific operation process, the cyclohexanone is first stirred at a temperature of 10 to 80° C., and the peracid solution is slowly added dropwise at a stirring speed of 10 to 600 rpm. After the addition of the peracid solution is completed, the mixture of the peracid solution and the cyclohexanone is reacted at 10 to 80° C. and 0.1 to 0.5 MPa for 1 to 10 hours. Specifically, the molar ratio of the peracid in the peracid solution to the cyclohexanone is 0.5 to 3:1.

[0065] The following examples further illustrate the method for preparing peroxyacids of the present invention. The examples are implemented based on the technical solution of the present invention, and provide detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to the following examples.

[0066] 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.

[0067] Phosphotungstic acid: Purchased from: Sinopharm Reagents, product purity > 99.9%;

[0068] Decatungstate: Purchased from: Sinopharm Reagents, product purity > 99.9%;

[0069] Pyridine: Purchased from: Sinopharm Reagent, product purity>99.9%;

[0070] Cyclohexanone: Purchased from: Sinopharm Reagents, product purity > 99.9%.

[0071] Test example:

[0072] The analysis method of peroxides such as hydrogen peroxide and peracid shall refer to the national standard "Peracetic Acid Solution GB / T19104-2021";

[0073] The analysis methods of materials such as caprolactone and cyclohexanone refer to the industry standard "Industrial ε-caprolactone HG / T 5618-2019";

[0074] The conversion rate of cyclohexanone is calculated as follows: X = (A 环己酮的初始峰面积 -A 反应后结束后环己酮峰面积 ) / A 环己酮的初始峰面积 *100%;

[0075] The selectivity calculation formula of caprolactone: S = A 己内酯峰面积 / (A 己内酯峰面积 *C 1校正因子 +A 剩余环己酮峰面积 *C 2校正因子 +A 重组分峰面积 *C 3校正因子)*100%.

[0076] Example 1

[0077] (1) 150 g of ethyl propionate, 150 g of propionic acid and 100 g of hydrogen peroxide (50 wt%) were weighed and placed in a reactor, 0.5 g of phosphotungstic acid (heteropoly acid) was added to the reactor, and the mixture was reacted at 70° C. and an absolute pressure of 0.1 MPa for 1 h to obtain a water-containing peroxypropionic acid product, and then the water-containing peroxypropionic acid product was placed in a reaction distillation tower, the bottom temperature of the reaction distillation tower was set to 80° C., the top temperature was set to 35° C., and the absolute pressure was set to 0.015 MPa. During the reaction, the reaction was stopped for 1.5 h, ethyl propionate and water formed an azeotrope and entered the top condenser, and the condensed material was in the form of oil and water phases, ethyl propionate was fully refluxed as the oil phase, and the water phase was fully extracted, and the generated anhydrous peroxy acid product was extracted from the bottom of the tower to obtain a peroxypropionic acid synthetic solution;

[0078] (2) The peroxypropionic acid synthetic solution obtained in step (1) is placed in a tank reactor, and 0.04 g of pyridine (stabilizer) is added at a stirring speed of 100 rpm, so that the molar ratio of pyridine to phosphotungstic acid (heteropoly acid) is 3:1. After the addition of pyridine is completed, the mixture of the peroxypropionic acid synthetic solution and pyridine is reacted at 50° C. and an absolute pressure of 0.1 MPa for 1 hour to obtain a peroxypropionic acid solution. According to calculations, the conversion rate of hydrogen peroxide is 99.3%, the selectivity of the peroxypropionic acid is 92%, and the concentration of the peroxypropionic acid in the peroxypropionic acid solution is 31.1%.

[0079] Application Example 1

[0080] 98 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C. The magnetic stirring was turned on at a stirring speed of 200 rpm, and the peroxypropionic acid solution obtained in Example 1 was slowly added dropwise to the cyclohexanone. The addition was completed after 0.5 h, and the reaction was continued at 55° C. and an absolute pressure of 0.1 MPa for 5 h to obtain a caprolactone solution. According to calculations, the conversion rate of cyclohexanone was 99.9%, and the selectivity of the caprolactone was 98%.

[0081] Example 2

[0082] (1) 150 g of ethyl propionate, 150 g of propionic acid and 100 g of hydrogen peroxide (50 wt%) were weighed and placed in a reactor, 0.5 g of phosphomolybdic acid (heteropoly acid) was added to the reactor, and the mixture was reacted at 70° C. and an absolute pressure of 0.1 MPa for 1 h to obtain a water-containing peroxypropionic acid product, and then the water-containing peroxypropionic acid product was placed in a reaction distillation tower, the bottom temperature of the reaction distillation tower was set to 80° C., the top temperature was set to 35° C., and the absolute pressure was set to 0.015 MPa. During the reaction, the reaction was allowed to stay for 1.5 h, ethyl propionate and water formed an azeotrope and entered the top condenser, and the condensed material was in the form of oil and water phases, ethyl propionate was fully refluxed as the oil phase, and the water phase was fully extracted, and the generated anhydrous peroxy acid product was extracted from the bottom of the tower to obtain a peroxypropionic acid synthetic solution;

[0083] (2) placing the peroxypropionic acid synthetic solution obtained in step (1) in a tank reactor, and adding pyridine at a stirring speed of 300 rpm, so that the molar ratio of pyridine to phosphomolybdic acid (heteropoly acid) is 10:1, and after the addition of pyridine is completed, reacting the mixture of the peroxypropionic acid synthetic solution and pyridine at 25° C. and an absolute pressure of 0.1 MPa for 1 hour to obtain a peroxypropionic acid solution. According to calculations, the conversion rate of hydrogen peroxide is 99.2%, the selectivity of the peroxypropionic acid solution is 84%, and the concentration of peroxypropionic acid in the peroxypropionic acid solution is 28.4%.

[0084] Application Example 2

[0085] 98 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C. The magnetic stirring was turned on at a stirring speed of 50 rpm, and the peroxypropionic acid solution obtained in Example 2 was slowly added dropwise to the cyclohexanone, with a molar ratio of peroxypropionic acid to cyclohexanone of 1.05:1. The addition was completed after 0.5 h, and the reaction was then allowed to stand at 65° C. and an absolute pressure of 0.1 MPa for 4.5 h to obtain a caprolactone solution. It was calculated that the conversion rate of cyclohexanone was 99.9%, and the selectivity of the caprolactone was 97%.

[0086] Example 3

[0087] (1) 150 g of ethyl propionate, 40.05 g of propionic acid and 200.25 g of hydrogen peroxide (50 wt%) were weighed and placed in a reactor, 10 g of decatungstic acid (isopolyacid) was added to the reactor, and the mixture was reacted at 70° C. and an absolute pressure of 0.1 MPa for 1 h to obtain a water-containing peroxypropionic acid product, and then the water-containing peroxypropionic acid product was placed in a reaction distillation tower, the bottom temperature of the reaction distillation tower was set to 80° C., the top temperature was set to 35° C., and the absolute pressure was set to 0.015 MPa. During the reaction, the reaction was stopped for 1.5 h, ethyl propionate and water formed an azeotrope and entered the top condenser, and the condensed material was in an oil-water two-phase state, ethyl propionate was fully refluxed as the oil phase, and the water phase was fully extracted, and the generated anhydrous peroxy acid product was extracted from the bottom of the tower to obtain a peroxypropionic acid synthetic solution;

[0088] (2) The peroxypropionic acid synthetic solution obtained in step (1) is placed in a tank reactor, and quinoline (stabilizer) is added at a stirring speed of 100 rpm, so that the molar ratio of quinoline to decatungstic acid (isopolyacid) is 30:1. After the addition of quinoline is completed, the mixture of the peroxypropionic acid synthetic solution and quinoline is reacted at 50° C. and an absolute pressure of 0.15 MPa for 1 hour to obtain a peroxypropionic acid solution. According to calculation, the conversion rate of hydrogen peroxide is 99.3%, the selectivity of the peroxypropionic acid solution is 75%, and the concentration of peroxypropionic acid in the peroxypropionic acid solution is 25.3%.

[0089] Application Example 3

[0090] 100 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C., magnetic stirring was turned on, and the stirring speed was 300 rpm. The peroxypropionic acid solution obtained in Example 3 was slowly added dropwise to the cyclohexanone, and the addition was completed after 0.5 h. The reaction was then allowed to stand at 65° C. and an absolute pressure of 0.4 MPa for 2 h to obtain a caprolactone solution. According to calculations, the conversion rate of cyclohexanone was 97.5%, and the selectivity of the caprolactone was 98%.

[0091] Example 4

[0092] The method of Example 1 is followed, except that in step (1), 0.5 g of sulfuric acid (98 wt%) is added to the reactor, and the reaction is carried out at 0° C. and an absolute pressure of 0.5 MPa for 15 h. In step (2), the stabilizer is replaced with aniline, and the molar ratio of aniline to sulfuric acid (acidic catalyst) is 15:1. The specific operation process includes the following steps:

[0093] (1) 150 g of ethyl propionate, 150 g of propionic acid and 100 g of hydrogen peroxide (50 wt%) were weighed and placed in a reactor, 0.5 g of sulfuric acid (concentration of 98 wt%) was added to the reactor, and the reaction was carried out at 0° C. and an absolute pressure of 0.5 MPa for 15 h to obtain a water-containing peroxypropionic acid product, and then the water-containing peroxypropionic acid product was placed in a reaction distillation tower, the tower bottom temperature of the reaction distillation tower was set to 80° C., the tower top temperature was set to 35° C., and the absolute pressure was set to 0.015 MPa. During the reaction process, the reaction was stopped for 1.5 h, ethyl propionate and water formed an azeotrope and entered the tower top condenser, and the condensed material was in an oil-water two-phase state, ethyl propionate was fully refluxed as the oil phase, and the water phase was fully extracted, and the generated anhydrous peroxy acid product was extracted from the tower bottom to obtain a peroxypropionic acid synthetic solution;

[0094] (2) The peroxypropionic acid synthesis solution obtained in step (1) is placed in a tank reactor, and 7.17 g of aniline (stabilizer) is added at a stirring speed of 200 rpm, so that the molar ratio of aniline to sulfuric acid (acid catalyst) is 15:1. After the addition of aniline is completed, the mixture of the peroxypropionic acid synthesis solution and aniline is reacted at 60° C. and an absolute pressure of 0.5 MPa for 1 hour to obtain a peroxypropionic acid solution. According to calculations, the conversion rate of hydrogen peroxide is 99.5%, the selectivity of the peroxypropionic acid solution is 90%, and the concentration of peroxypropionic acid in the peroxypropionic acid solution is 30.4%.

[0095] Application Example 4

[0096] 98 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C. The magnetic stirring was turned on at a stirring speed of 300 rpm. The molar ratio of peroxypropionic acid to cyclohexanone was 1.03:1. The peroxypropionic acid solution obtained in Example 4 was slowly added dropwise to the cyclohexanone for 0.5 h. The reaction was then allowed to stand at 50° C. and an absolute pressure of 0.1 MPa for 4 h to obtain a caprolactone solution. According to calculations, the conversion rate of cyclohexanone was 99.9%, and the selectivity of the caprolactone was 99.8%.

[0097] Example 5

[0098] The method of Example 1 is followed, except that in step (1), 0.5 g of phosphotungstic acid (heteropoly acid) is added to the reactor, and the reaction is carried out at 130° C. and an absolute pressure of 1 MPa for 20 h, and the stabilizer is replaced with ethanolamine. The specific operation process includes the following steps:

[0099] (1) 150 g of ethyl propionate, 150 g of propionic acid and 100 g of hydrogen peroxide (50 wt%) were weighed and placed in a reactor, 0.5 g of phosphotungstic acid (heteropoly acid) was added to the reactor, and the reaction was carried out at 13° C. and an absolute pressure of 1 MPa for 20 h to obtain a water-containing peroxypropionic acid product, and then the water-containing peroxypropionic acid product was placed in a reaction distillation tower, the bottom temperature of the reaction distillation tower was set to 80° C., the top temperature was set to 35° C., and the absolute pressure was set to 0.015 MPa. During the reaction, the reaction was stopped for 1.5 h, ethyl propionate and water formed an azeotrope and entered the top condenser, and the condensed material was in an oil-water two-phase state, ethyl propionate was fully refluxed as the oil phase, and the water phase was fully extracted, and the generated anhydrous peroxy acid product was extracted from the bottom of the tower to obtain a peroxypropionic acid synthetic solution;

[0100] (2) placing the peroxypropionic acid synthetic solution obtained in step (1) in a tank reactor, and adding ethanolamine (stabilizer) at a stirring speed of 300 rpm, so that the molar ratio of ethanolamine to phosphotungstic acid (heteropolyacid) is 6:1, and after the addition of ethanolamine is completed, reacting the mixture of the peroxypropionic acid synthetic solution and ethanolamine at 70° C. and an absolute pressure of 0.5 MPa for 1 hour to obtain a peroxypropionic acid solution. According to calculations, the conversion rate of hydrogen peroxide is 99.2%, the selectivity of the peroxypropionic acid solution is 85%, and the concentration of peroxypropionic acid in the peroxypropionic acid solution is 28.7%.

[0101] Application Example 5

[0102] 98 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C., magnetic stirring was turned on, and the stirring speed was 350 rpm. The peroxypropionic acid solution obtained in Example 5 was slowly added dropwise to the cyclohexanone, wherein the molar ratio of peroxypropionic acid to cyclohexanone was 1.02:1, and the addition was completed for 0.5 h. The reaction was then allowed to stand at 55° C. and an absolute pressure of 0.1 MPa for 5.5 h to obtain a caprolactone solution. It was calculated that the conversion rate of cyclohexanone was 99.3%, and the selectivity of the caprolactone was 98%.

[0103] Example 6

[0104] The method of Example 1 is followed, except that in step (1), the reaction conditions in the reaction distillation tower and the molar ratio of the stabilizer to the acid catalyst are adjusted. The specific operation process includes the following steps:

[0105] (1) 150 g of ethyl propionate, 150 g of propionic acid and 100 g of hydrogen peroxide (50 wt%) were weighed and placed in a reactor, 0.5 g of phosphotungstic acid (heteropoly acid) was added to the reactor, and the mixture was reacted at 70° C. and an absolute pressure of 0.1 MPa for 1 h to obtain a water-containing peroxypropionic acid product, and then the water-containing peroxypropionic acid product was placed in a reaction distillation tower, the bottom temperature of the reaction distillation tower was set to 70° C., the top temperature was set to 27° C., and the absolute pressure was set to 0.01 MPa. During the reaction, the reaction was stopped for 5 h, ethyl propionate and water formed an azeotrope and entered the top condenser, and the condensed material was in the form of oil and water phases, ethyl propionate was fully refluxed as the oil phase, and the water phase was fully extracted, and the generated anhydrous peroxy acid product was extracted from the bottom of the tower to obtain a peroxypropionic acid synthetic solution;

[0106] (2) The peroxypropionic acid synthetic solution obtained in step (1) is placed in a tank reactor, and 0.08 g of pyridine (stabilizer) is added at a stirring speed of 100 rpm, so that the molar ratio of pyridine to phosphotungstic acid (heteropolyacid) is 6:1. After the addition of pyridine is completed, the mixture of the peroxypropionic acid synthetic solution and pyridine is reacted at 55° C. and an absolute pressure of 0.1 MPa for 1 hour to obtain a peroxypropionic acid solution. According to calculations, the conversion rate of hydrogen peroxide is 99.7%, the selectivity of the peroxypropionic acid solution is 95%, and the concentration of peroxypropionic acid in the peroxypropionic acid solution is 32.1%.

[0107] Application Example 6

[0108] 50 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C. The magnetic stirring was turned on at a stirring speed of 200 rpm, and the peroxypropionic acid solution obtained in Example 6 was slowly added dropwise to the cyclohexanone. The addition was completed after 0.5 h, and the reaction was continued at 55° C. and 0.1 MPa for 5.5 h to obtain a caprolactone solution. According to calculation, the conversion rate of cyclohexanone was 99.8%, and the selectivity of the caprolactone was 97.8%.

[0109] Example 7

[0110] The method of Example 1 is implemented, except that ethyl propionate is replaced by acetonitrile, propionic acid is replaced by butyric acid, and heteropoly acid is replaced by nitric acid. The specific operation process includes the following steps:

[0111] (1) 150 g of acetonitrile, 150 g of butyric acid and 100 g of hydrogen peroxide (90 wt%) were weighed and placed in a reactor, 0.5 g of nitric acid (concentration of 25 wt%) was added to the reactor, and the mixture was reacted at 35° C. and an absolute pressure of 0.1 MPa for 1 h to obtain a water-containing peroxybutyric acid product, and then the water-containing peracetic acid product was placed in a reaction distillation tower, the bottom temperature of the reaction distillation tower was set to 80° C., the top temperature was set to 35° C., and the absolute pressure was set to 0.015 MPa. During the reaction, the reaction was stopped for 1.5 h, acetonitrile and water formed an azeotrope and entered the top condenser, and the condensed material was in an oil-water two-phase state, acetonitrile was fully refluxed as the oil phase, and the water phase was fully extracted, and the generated anhydrous peroxy acid product was extracted from the bottom of the tower to obtain a peroxybutyric acid synthetic solution;

[0112] (2) placing the peroxybutyric acid synthetic solution obtained in step (1) in a tank reactor, and adding pyridine (stabilizer) at a stirring speed of 100 rpm, so that the molar ratio of pyridine to nitric acid is 3:1, and after the addition of pyridine is completed, reacting the mixture of the peroxybutyric acid synthetic solution and pyridine at 50° C. and an absolute pressure of 0.1 MPa for 1 hour to obtain a peroxybutyric acid solution. According to calculations, the conversion rate of hydrogen peroxide is 98%, the selectivity of the peroxybutyric acid solution is 74%, and the concentration of peroxypropionic acid in the peroxybutyric acid solution is 25%.

[0113] Application Example 7

[0114] 50 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C. The magnetic stirring was turned on at a stirring speed of 200 rpm. The peroxybutyric acid solution obtained in Example 7 was slowly added dropwise to the cyclohexanone, and the molar ratio of peroxybutyric acid to cyclohexanone was 1:1. The addition was completed after 2.5 hours, and then the reaction was allowed to stand at 55° C. and an absolute pressure of 0.1 MPa for 5 hours to obtain a caprolactone solution. It was calculated that the conversion rate of cyclohexanone was 98.3%, and the selectivity of the caprolactone was 98%.

[0115] Example 8

[0116] The method of Example 1 is followed, except that the reaction conditions of the peroxypropionic acid synthetic solution and the stabilizer in step (2) are changed. The specific operation process includes the following steps:

[0117] (1) 150 g of ethyl propionate, 150 g of propionic acid and 100 g of hydrogen peroxide (50 wt%) were weighed and placed in a reactor, 0.5 g of phosphotungstic acid (heteropoly acid) was added to the reactor, and the mixture was reacted at 70° C. and an absolute pressure of 0.1 MPa for 1 h to obtain a water-containing peroxypropionic acid product, and then the water-containing peroxypropionic acid product was placed in a reaction distillation tower, the bottom temperature of the reaction distillation tower was set to 80° C., the top temperature was set to 35° C., and the absolute pressure was set to 0.015 MPa. During the reaction, the reaction was stopped for 1.5 h, ethyl propionate and water formed an azeotrope and entered the top condenser, and the condensed material was in the form of oil and water phases, ethyl propionate was fully refluxed as the oil phase, and the water phase was fully extracted, and the generated anhydrous peroxy acid product was extracted from the bottom of the tower to obtain a peroxypropionic acid synthetic solution;

[0118] (2) The peroxypropionic acid synthetic solution obtained in step (1) is placed in a tank reactor, and 0.04 g of pyridine (stabilizer) is added at a stirring speed of 100 rpm, so that the molar ratio of pyridine to phosphotungstic acid (heteropoly acid) is 3:1. After the addition of pyridine is completed, the mixture of the peroxypropionic acid synthetic solution and pyridine is reacted at 30° C. and an absolute pressure of 0.1 MPa for 0.2 h to obtain a peroxypropionic acid solution. According to calculations, the conversion rate of hydrogen peroxide is 99.3%, the selectivity of the peroxypropionic acid solution is 92%, and the concentration of peroxypropionic acid in the peroxypropionic acid solution is 31.1%.

[0119] Application Example 8

[0120] 98 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C. The magnetic stirring was turned on at a stirring speed of 200 rpm, and the peroxypropionic acid solution obtained in Example 8 was slowly added dropwise to the cyclohexanone. The addition was completed after 0.5 h, and the reaction was continued at 55° C. and an absolute pressure of 0.1 MPa for 2 h to obtain a caprolactone solution. According to calculations, the conversion rate of cyclohexanone was 99.9%, and the selectivity of the caprolactone was 96.7%.

[0121] Example 9

[0122] The method of Example 7 is followed, except that, based on the total weight of acetonitrile, butyric acid, hydrogen peroxide and nitric acid being 100 weight %, the content of acetonitrile is 50 weight %, the content of butyric acid is 35 weight %, the content of hydrogen peroxide is 10 weight %, and the content of nitric acid is 5 weight %. The specific operation process includes the following steps:

[0123] (1) 205 g of acetonitrile, 143.5 g of butyric acid and 41 g of hydrogen peroxide (80 wt%) were weighed and placed in a reactor, 10.5 g of nitric acid (concentration of 25 wt%) was added to the reactor, and the reaction was carried out at 70° C. and an absolute pressure of 0.1 MPa for 1 h to obtain a water-containing peroxybutyric acid product, and then the water-containing peroxybutyric acid product was placed in a reaction distillation tower, the bottom temperature of the reaction distillation tower was set to 80° C., the top temperature was set to 35° C., and the absolute pressure was set to 0.015 MPa. During the reaction, the reaction was stopped for 1.5 h, acetonitrile and water formed an azeotrope and entered the top condenser, and the condensed material was in an oil-water two-phase state, acetonitrile was fully refluxed as the oil phase, and the water phase was fully extracted, and the generated anhydrous peroxy acid product was extracted from the bottom of the tower to obtain a peroxybutyric acid synthetic solution;

[0124] (2) placing the peroxybutyric acid synthetic solution obtained in step (1) in a tank reactor, and adding pyridine (stabilizer) at a stirring speed of 100 rpm, so that the molar ratio of pyridine to nitric acid is 10:1, and after the addition of pyridine is completed, reacting the mixture of the peroxybutyric acid synthetic solution and pyridine at 50° C. and an absolute pressure of 0.1 MPa for 1 hour to obtain a peroxybutyric acid solution. According to calculations, the conversion rate of hydrogen peroxide is 99%, the selectivity of the peroxybutyric acid solution is 70%, and the concentration of peracetic acid in the peroxypropionic acid solution is 23.6%.

[0125] Application Example 9

[0126] 50 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C. The magnetic stirring was turned on at a stirring speed of 200 rpm. The peroxybutyric acid solution obtained in Example 9 was slowly added dropwise to the cyclohexanone, and the molar ratio of peroxybutyric acid to cyclohexanone was 0.95:1. The addition was completed after 0.5 h, and then the reaction was allowed to stand at 55° C. and an absolute pressure of 0.1 MPa for 2 h to obtain a caprolactone solution. It was calculated that the conversion rate of cyclohexanone was 97.9%, and the selectivity of the caprolactone was 97.6%.

[0127] Example 10

[0128] The method of Example 7 is followed, except that in step (1), the reaction conditions in the reactor and the reaction distillation column and the molar ratio of the stabilizer to the acid catalyst are adjusted. The specific operation process includes the following steps:

[0129] (1) 150 g of acetonitrile, 150 g of butyric acid and 100 g of hydrogen peroxide (90 wt%) were weighed and placed in a reactor, 0.5 g of nitric acid (concentration of 25 wt%) was added to the reactor, and the reaction was carried out at 20° C. and an absolute pressure of 1 MPa for 2 h to obtain a water-containing peroxybutyric acid product, and then the water-containing peroxybutyric acid product was placed in a reaction distillation tower, the bottom temperature of the reaction distillation tower was set to 35° C., the top temperature was set to 85° C., and the absolute pressure was set to 0.015 MPa. During the reaction process, the reaction was stopped for 3 h, acetonitrile and water formed an azeotrope and entered the top condenser, and the condensed material was in an oil-water two-phase state, acetonitrile was fully refluxed as the oil phase, and the water phase was fully extracted, and the generated anhydrous peroxy acid product was extracted from the bottom of the tower to obtain a peroxybutyric acid synthetic solution;

[0130] (2) placing the peroxybutyric acid synthetic solution obtained in step (1) in a tank reactor, and adding pyridine (stabilizer) at a stirring speed of 200 rpm, so that the molar ratio of pyridine to nitric acid is 6:1, and after the addition of pyridine is completed, reacting the mixture of the peroxybutyric acid synthetic solution and pyridine at 25° C. and an absolute pressure of 0.1 MPa for 1 hour to obtain a peroxybutyric acid solution. According to calculations, the conversion rate of hydrogen peroxide is 98.5%, the selectivity of the peroxybutyric acid solution is 72%, and the concentration of peroxybutyric acid in the peroxybutyric acid solution is 24.3%.

[0131] Application Example 10

[0132] 50 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C. The magnetic stirring was turned on at a stirring speed of 200 rpm, and the peroxybutyric acid solution obtained in Example 10 was slowly added dropwise to the cyclohexanone. The addition was completed after 0.5 h, and then the reaction was allowed to stand at 55° C. and an absolute pressure of 0.1 MPa for 2 h to obtain a caprolactone solution. According to calculations, the conversion rate of cyclohexanone was 96%, and the selectivity of the caprolactone was 95%.

[0133] Comparative Example 1

[0134] The method of Example 1 is followed, except that only step (1) is performed and step (2) is not performed, to obtain a peroxypropionic acid solution. According to calculations, the conversion rate of hydrogen peroxide is 97.5%, the selectivity of the peroxypropionic acid solution is 82%, and the concentration of peroxypropionic acid in the peroxypropionic acid solution is 27.7%.

[0135] Application Comparative Example 1

[0136] 98 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C. The magnetic stirring was turned on at a stirring speed of 200 rpm, and the peroxypropionic acid solution obtained in Comparative Example 1 was slowly added dropwise to the cyclohexanone. The addition was completed after 0.5 h, and the reaction was continued at 45° C. and 0.1 MPa for 2 h to obtain a caprolactone solution. The conversion rate of cyclohexanone was 73%, and the selectivity of the caprolactone was 27.5%.

[0137] Comparative Example 2

[0138] The method of Example 1 is followed, except that in step (2), the pyridine is replaced by ammonium chloride to obtain a peroxypropionic acid solution. According to calculations, the conversion rate of hydrogen peroxide is 99.2%, the selectivity of the peroxypropionic acid solution is 91%, and the concentration of peroxypropionic acid in the peroxypropionic acid solution is 30.7%.

[0139] Application Comparative Example 2

[0140] 98 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C. The magnetic stirring was turned on at a stirring speed of 200 rpm, and the peroxypropionic acid solution obtained in Comparative Example 2 was slowly added dropwise to the cyclohexanone, and the addition was completed for 0.5 h, and then the reaction was allowed to stand at 55° C. and 0.1 MPa for 1 h to obtain a caprolactone solution. The conversion rate of cyclohexanone was 85%, and the selectivity of the caprolactone was 17.2%.

[0141] Comparative Example 3

[0142] The method of Example 1 is followed, except that in step (2), pyridine is replaced by ethanol to obtain a peroxypropionic acid solution. According to calculations, the conversion rate of hydrogen peroxide is 99.3%, the selectivity of the peroxypropionic acid is 92%, and the concentration of the peroxypropionic acid in the peroxypropionic acid solution is 31.1%.

[0143] Application Comparative Example 3

[0144] 98 g of cyclohexanone was weighed and placed in a tank reactor, and the temperature was raised to 50° C., magnetic stirring was turned on, and the stirring speed was 200 rpm. The peroxypropionic acid solution obtained in Comparative Example 3 was slowly added dropwise to the cyclohexanone, and the addition was completed for 0.5 h. The reaction was then allowed to stand at 55° C. and 0.1 MPa for 1 h to obtain a caprolactone solution. The conversion rate of cyclohexanone was 89.2%, and the selectivity of the caprolactone was 15%.

[0145] Table 1

[0146]

[0147] As can be seen from Table 1, the use of the composition and method of the present invention to prepare the peracid product can improve the conversion rate of hydrogen peroxide in the reaction process, so that the conversion rate of hydrogen peroxide is greater than 95%, and the selectivity of the prepared peracid product is greater than 70%. The peracid product is used to prepare caprolactone, so that the conversion rate of cyclohexanone is greater than 95%, and the selectivity of the prepared caprolactone is greater than 95%.

[0148] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A catalyst composition, characterized in that The composition contains an acidic catalyst and a stabilizer, and the acidic catalyst and the stabilizer are stored independently, wherein the stabilizer is a nitrogen-containing alkaline compound, and the N atom has a lone pair of electrons.

2. The composition according to claim 1, characterized in that The molar ratio of the stabilizer to the acid catalyst is 1 to 30:1, preferably 3 to 10:

1.

3. The composition according to claim 1 or 2, characterized in that The stabilizer is selected from one or more of methylamine, ethylamine, triethylamine, trimethylamine, ethylenediamine, urea, ethanolamine, isopropylamine, tert-butylamine, aniline, benzylamine, cyclohexylamine, pyridine, lutidine, pyrrole, indole, acridine, carbazole and quinoline.

4. The composition according to any one of claims 1 to 3, characterized in that The acidic catalyst is selected from one or more of sulfuric acid, nitric acid, heteropoly acid and isopoly acid; Preferably, the heteropoly acid is selected from one or more of phosphomolybdic acid, phosphotungstic acid and silicotungstic acid; Preferably, the isopoly acid is selected from one or more of decatungstic acid, heptatungstic acid, octamolybdic acid and dodecamolybdic acid.

5. A method for preparing peroxyacid, characterized in that: The method comprises the following steps: (1) mixing an organic solvent, an organic acid, hydrogen peroxide and an acidic catalyst to obtain a peracid synthesis solution; (2) reacting the peroxyacid synthetic solution with a stabilizer; The stabilizer is a nitrogen-containing basic compound, and the N atom has a lone pair of electrons.

6. The method according to claim 5, characterized in that The molar ratio of the stabilizer to the acid catalyst is 1 to 30:1, preferably 3 to 10:

1.

7. The method according to claim 5 or 6, characterized in that: The stabilizer is selected from one or more of methylamine, ethylamine, triethylamine, trimethylamine, ethylenediamine, urea, ethanolamine, isopropylamine, tert-butylamine, aniline, benzylamine, cyclohexylamine, pyridine, lutidine, pyrrole, indole, acridine, carbazole and quinoline.

8. The method according to any one of claims 5 to 7, characterized in that: The acidic catalyst is selected from one or more of sulfuric acid, nitric acid, heteropoly acid and isopoly acid; Preferably, the heteropoly acid is selected from one or more of phosphomolybdic acid, phosphotungstic acid and silicotungstic acid; Preferably, the isopoly acid is selected from one or more of decatungstic acid, heptatungstic acid, octamolybdic acid and dodecamolybdic acid.

9. The method according to any one of claims 5 to 7, characterized in that: Based on the total weight of the organic solvent, organic acid, hydrogen peroxide and acidic catalyst as 100 weight %, the content of the organic solvent is 5 to 70 weight %, the content of the organic acid is 5 to 70 weight %, the content of the hydrogen peroxide is 5 to 70 weight %, and the content of the acidic catalyst is 0.01 to 15 weight %; Preferably, based on the total weight of the organic solvent, organic acid, hydrogen peroxide and acidic catalyst as 100 weight %, the content of the organic solvent is 10-50 weight %, the content of the organic acid is 10-50 weight %, the content of the hydrogen peroxide is 10-60 weight %, and the content of the acidic catalyst is 0.05-10 weight %.

10. The method according to any one of claims 5 to 7, characterized in that: The organic solvent is selected from one or more of ethyl acetate, propyl acetate, isobutyl acetate, propyl propionate, isopropyl propionate, ethyl propionate, butyl acetate, n-ethane, methylene chloride, dichlorohexane, cyclohexane, benzene and acetonitrile; Preferably, the organic acid is selected from one or more of formic acid, acetic acid, propionic acid and butyric acid.

11. The method according to claim 10, characterized in that In step (1), the mixing conditions include: temperature of 0 to 130° C., time of 0.05 to 30 h, and absolute pressure of 0.001 to 1 MPa.

12. The method according to claim 5 or 11, characterized in that: The concentration of peroxyacid in the peroxyacid synthetic solution is 5 to 50% by weight.

13. The method according to any one of claims 5 to 12, characterized in that: In step (2), the reaction conditions include: temperature of 10-50° C., time of 0.2-1.5 h, and absolute pressure of 0.1-0.3 MPa.

14. The method according to any one of claims 5 to 12, characterized in that: The concentration of the hydrogen peroxide solution is 10 to 80% by weight, preferably 25 to 50% by weight.

Images