CN103204792B - Preparation method of tert-butyl hydroperoxide - Google Patents

Abstract

The invention discloses a preparation method of tert-butyl hydroperoxide. Under oxidation reaction conditions, tert-butanol, an oxidant, a solvent and a catalyst are mixed and contacted, and the catalyst is characterized in that the catalyst is modified with a soluble zinc salt. Heteroatom Molecular Sieves.

Description

A kind of preparation method of tert-butyl hydroperoxide

technical field

The present invention relates to a method for preparing tert-butyl hydroperoxide, and more particularly to a method for catalytically oxidizing tert-butyl alcohol to prepare tert-butyl hydroperoxide.

Background technique

Tert-butyl hydroperoxide is a colorless transparent or yellow liquid, which is miscible with organic solvents such as ethanol and ether. It is stable below 75°C, loses oxygen at 90-100°C, and explodes at 250°C. Tert-butyl hydroperoxide is mainly used as a catalyst for polymerization reactions, and as an introduction agent for peroxide groups in substituent reactions. It is used for dyeing and printing cotton, viscose, silk, nylon and other fibers and their fabrics. Used for polyester/viscose blended fabric dyeing. Tert-butyl hydroperoxide can also be used as a drying agent for unsaturated melamine resin coatings, a polymerization initiator, and an intermediate in organic synthesis. The existing preparation methods mainly include: firstly, after diazotization of p-nitroaniline ortho-sulfonic acid, it is coupled with acid, then the nitro group in the coupled compound is reduced to amino group, then condensed with phosgene, and finally salted out and filtered and dried. The second is obtained by reacting tert-butanol with sulfuric acid to generate tert-butyl bisulfate, which is then reacted with hydrogen peroxide. Also add tert-butanol into the reaction pot, add hydrogen peroxide at 35°C under stirring, then raise the temperature to 50°C, add 70% sulfuric acid dropwise, react for 5 hours after the addition, keep the temperature at 55-60°C, and let it stand for stratification , take the upper oil layer and dry it with anhydrous sodium sulfate, filter to obtain tert-butyl hydroperoxide. It can be seen that the existing process has equipment corrosion and harmful discharge, which is extremely inconsistent with the development direction of environmental friendliness, and the by-products are cheap by-products, and the economic benefits are poor. Disclosed in CN1699339A is a method for preparing tert-butyl hydroperoxide. The method simply uses titanium-silicon molecular sieve as a catalyst and hydrogen peroxide as an oxidant, and the conversion rate of tert-butyl alcohol still has a large room for improvement.

Contents of the invention

Therefore, the purpose of the present invention is to provide a kind of environment-friendly and simple technology for the deficiency of existing technology, the method that tert-butyl hydroperoxide is prepared by catalytic oxidation of tert-butyl alcohol with hydrogen peroxide as oxidant.

The method for preparing tert-butyl hydroperoxide provided by the present invention is characterized in that the heteroatom molecular sieve modified by soluble zinc salt is used as a catalyst, and the tert-butyl hydroperoxide butanol, oxidant, solvent and catalyst are mixed and contacted, wherein the molar ratio of tert-butanol to oxidant is 1:1 to 10, and the mass ratio of solvent to catalyst is 0 to 200:1, and the soluble zinc salt modified hetero In the atomic molecular sieve, the molar ratio of the heteroatom molecular sieve (calculated by heteroatom) to the soluble zinc salt (calculated by zinc) is 0.05-10:1.

Compared with the traditional method, the method provided by the present invention overcomes the problems of complex traditional production process, equipment corrosion, and harmful discharge. It does not need to add any inhibitor or initiator to the raw material, and the production process is simple. It is a green synthesis process, and t The yield of butyl hydroperoxide is high.

Detailed ways

In the method for preparing tert-butyl hydroperoxide by catalytically oxidizing tert-butyl alcohol provided by the present invention, the catalyst is a heteroatom molecular sieve modified by a soluble zinc salt. Heteroatom molecular sieves are molecular sieves containing one or more heteroatoms selected from titanium, vanadium, iron, cobalt, tin, cerium and other heteroatoms in the molecular sieve framework structure, such as titanium silicon molecular sieves, vanadium silicon molecular sieves, iron silicon molecular Molecular sieves, tin-silicon molecular sieves, cerium-silicon molecular sieves, etc., among which titanium-silicon molecular sieves are preferred. The titanium-silicon molecular sieve is one or more of TS-1, TS-2, Ti-MCM-22, Ti-MCM-41, Ti-SBA-15, Ti-ZSM-48, more preferably hetero The atomic molecular sieve is titanium silicon molecular sieve TS-1. The most preferred heteroatom molecular sieve is a titanium-silicon molecular sieve with an MFI structure and a hollow structure grain, the radial length of the cavity part of the hollow structure is 5 to 300 nanometers, and the titanium-silicon molecular sieve is at 25 ° C, P/P ₀ =0.10 and the adsorption time is 1 hour, the measured benzene adsorption amount is at least 70 mg/g, and there is a hysteresis loop between the adsorption isotherm and the desorption isotherm of the low-temperature nitrogen adsorption of the titanium silicon molecular sieve.

In the method provided by the invention, the catalyst is a heteroatom molecular sieve modified by a soluble zinc salt, and the soluble zinc salt is selected from zinc phosphate, zinc nitrate, zinc chloride, zinc sulfate, zinc gluconate, zinc acetate, zinc bromide , one or more of zinc fluoride or dizinc hydrogen phosphate.

In the heteroatom molecular sieve modified by soluble zinc salt, the molar ratio of heteroatom molecular sieve (calculated by heteroatom) to soluble zinc salt (calculated by zinc) is 0.05-10:1, preferably 0.1-5:1. The heteroatom molecular sieve modified by soluble zinc salt is obtained by mixing the soluble zinc salt aqueous solution and the heteroatom molecular sieve uniformly, followed by drying and roasting. The drying and roasting conditions are well known to those skilled in the art, and there is no special requirement here. Generally, it is treated in an air atmosphere at room temperature to 200° C. for 1 to 8 hours; generally, the temperature of the calcination can be 200 to 800° C. and the time can be 1 to 12 hours. The firing can be performed under air or oxygen atmosphere.

In the method provided by the invention, the oxidizing agent is hydrogen peroxide, which can be a pure product, but it is preferably an aqueous solution of hydrogen peroxide from the viewpoint of economy and safety, and the mass percentage of hydrogen peroxide is selected from 5% ~90%, preferably 20%~70%.

In the preparation method provided by the present invention, it can be realized under solvent-free conditions. The inventors found that the reaction performance can be improved when a certain solvent is introduced during the implementation process. Therefore, in the preparation method provided by the present invention, a solvent can also be introduced as required, and the solvent is preferably introduced. Described solvent is selected from the ketones such as methanol, ethanol or acetone, methyl ethyl ketone or the nitriles such as acetonitrile, propionitrile, benzyl nitrile or their mixture, preferably acetonitrile, acetone, methanol or their mixture, more preferably acetone, methanol and/or acetonitrile.

In the method provided by the present invention, the preferred ratio of raw materials is as follows: the molar ratio of tert-butanol to oxidant is preferably 1:1-5, and the mass ratio of solvent to catalyst is preferably 0-150:1. The amount between the raw material tert-butanol and the catalyst is not specifically limited, as long as the present invention can be realized, generally the mass ratio of tert-butanol to the catalyst is 0.5-100:1.

In the method provided by the present invention, the reaction temperature is preferably 40-120° C., and the reaction pressure is preferably 0.1-2.5 MPa.

In the preparation method provided by the present invention, there is no special requirement on the order of addition, tert-butanol can be added first, and oxidant or solvent can also be added first.

The present invention will be further described below by embodiment, but content of the present invention is not limited thereby.

In Examples and Comparative Examples, all reagents used are commercially available chemically pure reagents, wherein hydrogen peroxide is an aqueous solution with a mass concentration of 30%. The titanium-silicon molecular sieve used was prepared according to the method of the prior art (Zeolites, 1992, Vol. 12 pages 943-950). The hollow titanium-silicon molecular sieve used is the titanium-silicon molecular sieve industrial product described in Example 6 of Chinese Patent CN1301599A. The titanium-silicon molecular sieve has an MFI structure. There is Hysteresis ring, the grains are hollow grains and the radial length of the cavity part is 15-180 nanometers; the titanium-silicon molecular sieve sample is measured under the conditions of 25°C, P/P ₀ =0.10, and adsorption time of 1 hour. Adsorption capacity is 78 mg/g)

The preparation process of the titanium-silicon molecular sieve modified by the soluble zinc salt of the catalyst in the embodiment is that under normal temperature and pressure, a certain amount of soluble zinc salt solution and titanium-silicon molecular sieve are mixed evenly according to the needs, and then transferred to the oven under the air atmosphere Dry at 120°C for 5 hours, and finally bake at 550°C for 5 hours in a muffle furnace. For the molar ratio of titanium-silicon molecular sieve (calculated as titanium) to soluble zinc salt (calculated as zinc) in the catalyst preparation process, refer to the description in each embodiment for details.

In Comparative Examples and Examples:

Comparative example 1

This comparative example illustrates the reaction conditions and results of t-butanol and hydrogen peroxide in the absence of a catalyst.

The tert-butanol, hydrogen peroxide and solvent are reacted at a temperature of 60° C. and a pressure of 1.5 MPa according to the molar ratio of tert-butanol to hydrogen peroxide of 1:2, wherein the mass of solvent methanol is 20 g. After 2 hours of reaction, the conversion of tert-butanol and the selectivity to tert-butyl hydroperoxide were 0%.

Comparative example 2

This comparative example illustrates the reaction conditions and results of tert-butanol and hydrogen peroxide under the condition that the catalyst titanium-silicon molecular sieve exists alone.

The tert-butanol, hydrogen peroxide, solvent and catalyst titanium silicon molecular sieve are 2: 7 according to the mol ratio of tert-butanol and hydrogen peroxide, the mass ratio of solvent methanol and catalyst is 20: 1, the mass ratio of tert-butanol and catalyst The ratio is 10:1, and the reaction is carried out at a temperature of 80° C. and a pressure of 1.5 MPa. The results of the reaction for 2 hours were as follows: the conversion rate of tert-butyl alcohol was 26%; the selectivity of tert-butyl hydroperoxide was 88%.

Comparative example 3

This comparative example illustrates the reaction conditions and results of tert-butanol and hydrogen peroxide under the condition that the catalyst soluble zinc salt (zinc phosphate) exists alone.

With tert-butanol, hydrogen peroxide, solvent and catalyst (zinc phosphate) according to the mol ratio of tert-butanol and hydrogen peroxide is 1: 4, the mass ratio of solvent acetone and catalyzer is 40: 1, the mass ratio of tert-butanol and catalyzer The mass ratio is 10:1, and the reaction is carried out at a temperature of 60° C. and a pressure of 2.5 MPa. The result of reacting for 2 hours is as follows: the conversion rate of tert-butanol is 3%; the selectivity of tert-butyl hydroperoxide is 6%.

Example 1

The mol ratio of tert-butanol, hydrogen peroxide, solvent and catalyst (molar ratio 0.2: 1 of titanium silicon molecular sieve and zinc nitrate) is 1: 2 according to the mol ratio of tert-butanol and hydrogen peroxide, and the mass ratio of solvent acetonitrile and catalyzer is 20:1, the mass ratio of tert-butanol to catalyst is 10:1, and the reaction is carried out at a temperature of 50° C. and a pressure of 1.5 MPa. The results of the reaction for 2 hours were as follows: the conversion rate of tert-butyl alcohol was 34%; the selectivity of tert-butyl hydroperoxide was 94%.

Example 2

The mol ratio of tert-butanol, hydrogen peroxide, solvent and catalyst (molar ratio 1: 1 of titanium silicon molecular sieve and zinc phosphate) is 1: 3 according to the mol ratio of tert-butanol and hydrogen peroxide, and the mass ratio of solvent acetone and catalyzer is 50:1, the mass ratio of tert-butanol to catalyst is 20:1, and the reaction is carried out at a temperature of 60° C. and a pressure of 2.5 MPa. The results of the reaction for 2 hours were as follows: the conversion rate of tert-butyl alcohol was 45%; the selectivity of tert-butyl hydroperoxide was 96%.

Example 3

The mol ratio of tert-butanol, hydrogen peroxide, solvent and catalyst (molar ratio 0.1: 1 of titanium silicon molecular sieve and zinc sulfate) is 2: 9 according to the mol ratio of tert-butanol and hydrogen peroxide, and the mass ratio of solvent acetic acid and catalyzer is 60:1, the mass ratio of tert-butanol to catalyst is 1:1, and the reaction is carried out at a temperature of 100° C. and a pressure of 0.5 MPa. The results of the reaction for 2 hours were as follows: the conversion rate of tert-butyl alcohol was 73%; the selectivity of tert-butyl hydroperoxide was 92%.

Example 4

With tert-butanol, hydrogen peroxide, solvent and catalyst (the molar ratio of titanium silicon molecular sieve and dizinc hydrogen phosphate 2: 1) is 1: 4 according to the mol ratio of tert-butanol and hydrogen peroxide, the mass of solvent methanol and catalyst The ratio is 35:1, the mass ratio of tert-butanol to catalyst is 50:1, and the reaction is carried out at a temperature of 40° C. and a pressure of 0.5 MPa. The results of the reaction for 2 hours were as follows: the conversion rate of tert-butyl alcohol was 71%; the selectivity of tert-butyl hydroperoxide was 96%.

Example 5

The mol ratio of tert-butanol, hydrogen peroxide, solvent and catalyst (molar ratio of titanium silicon molecular sieve and zinc chloride 5: 1) is 1: 2 according to the mol ratio of tert-butanol and hydrogen peroxide, the mass ratio of solvent acetonitrile and catalyst 5:1, the mass ratio of tert-butanol to catalyst is 70:1, and the reaction is carried out at a temperature of 80° C. and a pressure of 0.5 MPa. The results of the reaction for 2 hours were as follows: the conversion rate of tert-butyl alcohol was 82%; the selectivity of tert-butyl hydroperoxide was 94%.

Example 6

The mol ratio of tert-butanol, hydrogen peroxide, solvent and catalyst (molar ratio 0.2: 1 of titanium silicon molecular sieve and zinc acetate) is 3: 8 according to the mol ratio of tert-butanol and hydrogen peroxide, the mass ratio of solvent benzyl nitrile and catalyst The mass ratio of tert-butanol to catalyst is 100:1, and the reaction is carried out at a temperature of 90° C. and a pressure of 1.5 MPa. The results of the reaction for 2 hours were as follows: the conversion rate of tert-butyl alcohol was 79%; the selectivity of tert-butyl hydroperoxide was 95%.

Example 7

The mol ratio of tert-butanol, hydrogen peroxide, solvent and catalyst (molar ratio 0.3: 1 of titanium silicon molecular sieve and zinc bromide) is 1: 5 according to the mol ratio of tert-butanol and hydrogen peroxide, solvent (equal volume ratio acetonitrile and The mass ratio of acetone) to the catalyst is 200:1, the mass ratio of tert-butanol to the catalyst is 0.5:1, and the reaction is carried out at a temperature of 60° C. and a pressure of 0.5 MPa. The results of the reaction for 2 hours were as follows: the conversion rate of tert-butyl alcohol was 65%; the selectivity of tert-butyl hydroperoxide was 91%.

Example 8

The mol ratio of tert-butanol, hydrogen peroxide, solvent and catalyst (molar ratio 0.5: 1 of titanium silicon molecular sieve and zinc gluconate) is 1: 2 according to the mol ratio of tert-butanol and hydrogen peroxide, the mass of solvent propionitrile and catalyzer The ratio is 10:1, the mass ratio of tert-butanol to catalyst is 30:1, and the reaction is carried out at a temperature of 70° C. and a pressure of 1.5 MPa. The results of the reaction for 2 hours were as follows: the conversion rate of tert-butyl alcohol was 84%; the selectivity of tert-butyl hydroperoxide was 93%.

Example 9

The mol ratio of tert-butanol, hydrogen peroxide, solvent and catalyst (molar ratio of titanium silicon molecular sieve and zinc fluoride 0.8: 1) is 1: 4 according to the mol ratio of tert-butanol and hydrogen peroxide, the mass ratio of solvent acetonitrile and catalyst The mass ratio of tert-butanol to catalyst is 90:1, and the reaction is carried out at a temperature of 120° C. and a pressure of 0.1 MPa. The result of reacting for 1 hour was as follows: the conversion rate of tert-butyl alcohol was 91%; the selectivity of tert-butyl hydroperoxide was 93%.

Example 10

According to the method of Example 1, tert-butyl alcohol was oxidized to prepare tert-butyl hydroperoxide. The difference is that the molar ratio of tert-butanol to hydrogen peroxide becomes 1:1. After 2 hours of reaction, the conversion rate of tert-butanol was 12%; the selectivity of tert-butyl hydroperoxide was 79%.

Example 11

According to the method of Example 5, tert-butyl alcohol was oxidized to prepare tert-butyl hydroperoxide. The difference is that the molar ratio of titanium silicon molecular sieve and zinc chloride in the catalyst becomes 12:1. After 2 hours of reaction, the conversion rate of tert-butanol was 76%; the selectivity of tert-butyl hydroperoxide was 76%.

Example 12

According to the method of Example 6, tert-butyl alcohol was oxidized to prepare tert-butyl hydroperoxide. The difference is that zinc acetate is replaced by equimolar zinc chloride. After reacting for 2 hours, the conversion rate of tert-butanol was 85%; the selectivity of tert-butyl hydroperoxide was 97%.

Example 13

According to the method of Example 9, tert-butyl alcohol was oxidized to prepare tert-butyl hydroperoxide. The difference is that the solvent acetonitrile is replaced by phenylacetonitrile. After 2 hours of reaction, the conversion rate of tert-butanol was 72%; the selectivity of tert-butyl hydroperoxide was 86%.

Example 14

With tert-butanol, hydrogen peroxide, solvent and catalyst (the molar ratio of vanadium-silicon molecular sieve and zinc acetate prepared according to the method described in Chinese patent CN1840477A embodiment 1 is 2: 1, wherein Si/heteroatom molar ratio in the vanadium-silicon molecular sieve is 80:1) according to the mol ratio of tert-butanol and hydrogen peroxide is 2:9, the mass ratio of solvent acetic acid and catalyst is 60:1, the mass ratio of tert-butanol and catalyst is 10:1, at a temperature of 100 The reaction was carried out at a temperature of 0.5 MPa. The result of reacting for 2 hours was as follows: the conversion rate of tert-butyl alcohol was 79%; the selectivity of tert-butyl hydroperoxide was 86%.

Example 15

With tert-butanol, hydrogen peroxide, solvent and catalyst (according to the molar ratio of tin silicon molecular sieve and zinc bromide prepared by the method described in J.Mol.Catal.A:Chem., 1996,105:149～158: 1, wherein the molar ratio of Si/heteroatom in the tin-silicon molecular sieve is 60: 1) according to the mol ratio of tert-butanol and hydrogen peroxide is 1: 4, the mass ratio of solvent methanol and catalyst is 35: 1, tert-butanol and The mass ratio of the catalyst is 5:1, and the reaction is carried out at a temperature of 40° C. and a pressure of 0.5 MPa. The results of the reaction for 2 hours were as follows: the conversion rate of tert-butyl alcohol was 67%; the selectivity of tert-butyl hydroperoxide was 97%.

Example 16

With tert-butanol, hydrogen peroxide, solvent and catalyst (according to the molar ratio of titanium silicon molecular sieve Ti-Beta and zinc gluconate prepared by the method described in J.Chem.Soc.Chem.Commun., 1997,677～678 0.2:1, wherein Si/heteroatom molar ratio in the titanium silicon molecular sieve is 30:1) According to the molar ratio of tert-butanol and hydrogen peroxide is 1:2, the mass ratio of solvent acetonitrile and catalyst is 5:1, tert-butyl The mass ratio of alcohol to catalyst is 70:1, and the reaction is carried out at a temperature of 80° C. and a pressure of 0.5 MPa. The results of the reaction for 2 hours were as follows: the conversion rate of tert-butyl alcohol was 78%; the selectivity of tert-butyl hydroperoxide was 85%.

Example 17

With tert-butanol, hydrogen peroxide, solvent and catalyst (the molar ratio of zinc fluoride and titanium silicon molecular sieve Ti-MCM-41 prepared according to the method described in Chem.Commun., 1994, 147～148 is 0.2: 1, Wherein the molar ratio of Si/heteroatom in the titanium silicon molecular sieve is 40: 1) according to the mol ratio of tert-butanol and hydrogen peroxide is 3: 8, the mass ratio of solvent benzyl nitrile and catalyzer is 20: 1, tert-butanol and catalyzer The mass ratio is 10:1, and the reaction is carried out at a temperature of 90° C. and a pressure of 1.5 MPa. The results of the reaction for 2 hours were as follows: the conversion rate of tert-butyl alcohol was 71%; the selectivity of tert-butyl hydroperoxide was 89%.

From Examples 1 to 17 and Comparative Examples 1 to 3, it can be seen that the conversion rate of tert-butanol using soluble zinc salt-modified titanium-silicon molecular sieves as catalysts in the present invention is significantly higher than that of unmodified Comparative samples such as titanium-silicon molecular sieves.

Claims (9)

1. a preparation method of tert-butyl hydroperoxide, under oxidation reaction conditions, tert-butyl alcohol, oxidizing agent, solvent and catalyzer are mixed contact, it is characterized in that described catalyzer is the heteroatom modified with soluble zinc salt Molecular sieves, the heteroatom molecular sieves are titanium-silicon molecular sieves, vanadium-silicon molecular sieves or tin-silicon molecular sieves, and the oxidizing agent is hydrogen peroxide. 2. The method according to claim 1, characterized in that the method is carried out at a temperature of 20-180° C. and a pressure of 0.1-3 MPa, wherein the molar ratio of tert-butanol to oxidant is 1:1-10, and the solvent The mass ratio of the heteroatom molecular sieve to the catalyst is 0-200:1. In the heteroatom molecular sieve modified by the soluble zinc salt, the molar ratio of the heteroatom molecular sieve to the soluble zinc salt is 0.05-10:1, and the heteroatom molecular sieve is calculated as a heteroatom , the soluble zinc salt is calculated as zinc. 3. according to the method for claim 1, wherein, described titanium silicon molecular screening is from TS-1, TS-2, Ti-MCM-22, Ti-MCM-41, Ti-SBA-15, Ti-ZSM-48 one or more of them. 4. according to the method for claim 1, wherein, described heteroatom molecular sieve is the titanium-silicon molecular sieve of the MFI structure of hollow structure grain, the radial length of the cavity part of its hollow structure is 5～300 nanometers, and the described The benzene adsorption measured by the titanium-silicon molecular sieve under the conditions of 25°C, P/P ₀ =0.10, and an adsorption time of 1 hour is at least 70 mg/g. The adsorption isotherm and desorption of the low-temperature nitrogen adsorption of the titanium-silicon molecular sieve There is a hysteresis loop between the isotherms. 5. according to the method for claim 1, wherein, described soluble zinc salt is selected from zinc phosphate, zinc nitrate, zinc chloride, zinc sulfate, zinc gluconate, zinc acetate, zinc bromide, zinc fluoride and hydrogen phosphate One or more of zinc. 6. according to the method for claim 1, wherein, tert-butanol and oxygenant molar ratio are 1: 2～5, solvent and catalyst mass ratio are 5～150: 1, tert-butanol and catalyst mass ratio are 0.5～100: 1 . 7. according to the method for claim 1, it is characterized in that with the heteroatom molecular sieve of soluble zinc salt modification as catalyzer, under the condition that temperature is 40～120 ℃ and pressure is 0.1～2.5MPa, tert-butanol, oxidizing agent, The solvent and the catalyst are mixed and contacted. 8. according to the method for claim 1, wherein, described catalyzer is the titanium-silicon molecular sieve of soluble zinc salt modification, and the mol ratio of titanium-silicon molecular sieve and soluble zinc salt is 0.1～5: 1, and titanium-silicon molecular sieve is in titanium, Soluble zinc salts are calculated as zinc. 9. The method according to claim 1, wherein the heteroatom molecular sieve modified by the soluble zinc salt is obtained by mixing the soluble zinc salt aqueous solution and the heteroatom molecular sieve uniformly, drying and roasting.