Catalyst for preparing benzaldehyde by direct oxidation of toluene and preparation method thereof

A catalyst and benzaldehyde technology, applied in the field of industrial catalysis, can solve the problems of uneconomical industrial production, high reaction temperature, and difficult product separation, and achieve the effects of easy separation and purification, mild reaction conditions, and enhanced interaction

Active Publication Date: 2018-03-23
YANCHENG CITY CHUNZHU AROMA
View PDF5 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The direct oxidation of toluene to generate benzaldehyde under gas phase or liquid phase conditions is a relatively economical and environmentally friendly method. Chinese patent CN1068755 discloses a method for preparing benzaldehyde by gas phase oxidation of toluene. The selectivity of benzaldehyde prepared by this method reaches 60%, and the one-way yield of benzaldehyde can reach 16%. The method of direct oxidation of toluene through the gas phase method mainly has the defects of high reaction temperature and easy over-oxidation of toluene, and the selectivity of benzaldehyde decreases especially when the conversion rate is increased.
There are many reports about the direct oxidation of benzaldehyde under liquid phase conditions. As early as 2004, the Chinese patent No. CN1528726 disclosed a method of preparing benzene by liquid phase oxidation of toluene in an acidic or neutral ionic liquid and acetic acid mixed solvent. The method of formaldehyde is to oxidize toluene under the condition of 115~120 ℃. When the conversion rate of toluene is 42%, the selectivity of benzaldehyde is only 48%. This method uses a large number of expensive ionic liquid and acetic acid solvent, which greatly improves the production cost, and product separation is difficult, and industrial production is uneconomical. The patent CN02143361.5 of Dalian Institute of Chemical Physics discloses a preparation method for a catalyst for the oxidation of toluene to benzaldehyde. The active components of the catalyst are zirconium and other transition metals and alkali metals Or alkaline earth metal etc., use this catalyzer, at temperature 180-195 ℃, feed oxygen, react under the condition of pressure 0.8-1.2MPa, when toluene conversion rate is 13%, the selectivity of benzaldehyde is 86.6%, this method catalyst The preparation process is relatively complicated, and the oxidation is not easy to control in the aldehyde stage, and it is easier to generate benzoic acid
[0005] In summary, there is not yet a method for the production of benzaldehyde with simple reaction, energy saving and environmental protection, easy separation and recovery of product and solvent, high toluene conversion rate and benzaldehyde selectivity in the reaction

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Catalyst for preparing benzaldehyde by direct oxidation of toluene and preparation method thereof
  • Catalyst for preparing benzaldehyde by direct oxidation of toluene and preparation method thereof
  • Catalyst for preparing benzaldehyde by direct oxidation of toluene and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] A catalyst for the direct oxidation of toluene to produce benzaldehyde, comprising the following components: 80wt% magnesia-alumina composite oxide carrier, wherein the molar ratio of magnesia to alumina is 1, cerium 10wt%, cobalt 3wt%, copper 5wt% , Nickel 2wt%.

[0024] The preparation method of above-mentioned catalyst comprises the steps:

[0025] 1) Weigh 150g Al(NO 3 ) 3 9H 2 O and 51.3g Mg(NO 3 ) 2 ·6H 2 O was dissolved in 1200 mL of deionized water to make a total concentration of 0.5 mol L -1 Mixed salt solution, weigh 80g NaOH and dissolve in 400ml deionized water to prepare 5mol L -1 Add the NaOH solution drop by drop to the mixed salt solution under stirring conditions, keep the pH value of the system at 9-10 during the dropwise addition, continue stirring and aging for 3 hours after the NaOH solution is added dropwise, and the obtained product Filter, wash with deionized water repeatedly 3 times, place in a constant temperature drying oven at 100°C ...

Embodiment 2

[0029] A catalyst for the direct oxidation of toluene to produce benzaldehyde, comprising the following components: 90wt% magnesia-alumina composite oxide carrier, wherein the molar ratio of magnesia to alumina is 1, cerium 4wt%, cobalt 5wt%, copper 0.5wt% %, nickel 0.5wt%.

[0030] The preparation method of above-mentioned catalyst comprises the steps:

[0031] 1) Weigh 150g Al(NO 3 ) 3 9H 2 O and 51.3gMg(NO 3 ) 2 ·6H 2 O was dissolved in 1200 mL of deionized water to make a total concentration of 0.5 mol L -1 Mixed salt solution, weigh 80g NaOH and dissolve in 400ml deionized water to prepare 5mol L -1 Add the NaOH solution drop by drop to the mixed salt solution under stirring conditions, keep the pH value of the system at 9-10 during the dropwise addition, continue stirring and aging for 3 hours after the NaOH solution is added dropwise, and the obtained product Filter, wash with deionized water repeatedly 3 times, place in a constant temperature drying oven at 100...

Embodiment 3

[0035] A catalyst for direct oxidation of toluene to produce benzaldehyde, comprising the following components: 85wt% magnesia-alumina composite oxide carrier, wherein the molar ratio of magnesia to alumina is 2, cerium 6wt%, cobalt 5wt%, copper 3wt% , Nickel 1wt%.

[0036] The preparation method of above-mentioned catalyst comprises the steps:

[0037] 1) Weigh 39.9g AlCl 3 and 28.8g MgCl 2 Dissolve in 1200mL deionized water to make a total concentration of 0.5mol L -1 Mixed salt solution, weigh 80g NaOH and dissolve in 400ml deionized water to prepare 5mol L -1 Add the NaOH solution drop by drop to the mixed salt solution under stirring conditions, keep the pH value of the system at 9-10 during the dropwise addition, continue stirring and aging for 3 hours after the NaOH solution is added dropwise, and the obtained product Filter, wash with deionized water repeatedly 3 times, place in a constant temperature drying oven at 100°C and dry, after drying, grind and place in a...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a catalyst for catalyzing direct oxidation of toluene to prepare benzaldehyde and a preparation method thereof. The catalyst comprises the following components in percentage by weight: 85 to 90 wt% of magnesium oxide and alumina composite oxide carrier; 0.5 to 10 wt% of cerium, 0.5 to 5 wt% of cobalt, 0.1 to 5 wt% of copper, and 0.5 to 2 wt% of nickel, wherein the mole ratio of magnesium oxide to alumina is 1-2. The catalyst takes a mixture of magnesium oxide and alumina as the carrier, can directly catalyze the oxidation of toluene to prepare benzaldehyde, and has the advantages of high toluene conversion rate, high benzaldehyde selectivity, high reaction stability, excellent performance, and mild reaction conditions. Moreover, the reaction product and the reactants are in two phases, and thus separation and purification become easier.

Description

technical field [0001] The invention relates to a catalyst, in particular to a catalyst for directly oxidizing toluene to produce benzaldehyde and a preparation method thereof, belonging to the technical field of industrial catalysis. Background technique [0002] Benzaldehyde is an important fine chemical product, which is widely used in industrial fields such as medicine, dyestuff, fragrance, pesticide and materials. The present disclosed production method of preparing benzaldehyde mainly contains following three kinds: toluene chlorination hydrolysis method, benzoic acid (ester) reduction method and toluene direct oxidation method. [0003] Chlorine is inevitably contained in the benzaldehyde produced by chlorination and hydrolysis of toluene, and chlorine cannot be contained in benzaldehyde used in industries such as medicine and spices. Therefore, the application range of benzaldehyde produced by chlorination and hydrolysis is limited. limits. Benzoic acid reduction m...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): B01J23/83C07C47/54C07C45/36
Inventor 谷列先朱得伟黄埔
Owner YANCHENG CITY CHUNZHU AROMA
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products