A post-treatment method for phenol hydrogenation pd@cn catalyst

Abstract

The invention relates to a post-treatment method of a phenol hydrogenation Pd@CN catalyst and belongs to the technical field of catalysis. The post-treatment method comprises the following steps: after carrying out phenol hydrogenation reaction, filtering to separate a Pd@CN catalyst; putting the Pd@CN catalyst into a container and adding de-ionized water; washing for a plurality of times under certain temperature and rotary speed; filtering when a solution is hot and immersing in water. By adopting the post-treatment method provided by the invention, the Pd@CN catalyst can be effectively recycled in a phenol hydrogenation process for producing cyclohexanone and the catalysis performance is stable. According to the post-treatment method, cyclic utilization of resources is realized, the cost is reduced and energy sources are saved; green production of a process of producing cyclohexanone through one-step phenol hydrogenation is facilitated.

Description

technical field

[0001] The invention relates to a post-treatment method of a phenol hydrogenation Pd@CN catalyst, in particular to a post-treatment method of a Pd@CN catalyst used in a hydrogenation process, and belongs to the technical field of catalysis. Background technique

[0002] Cyclohexanone is an important organic chemical raw material, mainly used in the production of caprolactam and adipic acid. In industry, it is mainly produced by cyclohexane oxidation. However, cyclohexane oxidation needs to be carried out under high temperature and high pressure, and many by-products will be generated, causing serious environmental pollution. At present, the one-step hydrogenation of phenol to cyclohexanone has attracted widespread attention due to its environmental friendliness and low energy consumption.

[0003] The reaction mechanism of one-step hydrogenation of phenol to cyclohexanone is as follows: phenol chemically adsorbs on the surface of the carrier, and reacts wit...

Examples

Embodiment 1

[0025] The reacted mixture was filtered through filter paper to separate the Pd@CN catalyst and solution. Put 6.4g of the recovered Pd@CN catalyst into a 1000mL beaker, add 500mL of deionized water, and stir at 70°C for 30min at a stirring rate of 400r / min. Filtrate while it is hot, the filtration temperature is controlled at 60°C, and the washed Pd@CN catalyst is recovered. Repeat the above washing steps three times. The Pd@CN catalyst washed three times was soaked in 200 mL deionized water.

[0026] The Pd@CN catalyst washed three times was added to the reactor together with 200mL deionized water, and used in the experiment of hydrogenation of phenol to cyclohexanone. The reaction was stopped after 2 hours, and it was recycled 5 times under the subsequent treatment method. The results are as follows figure 2 shown. The Pd@CN catalyst maintained good catalytic activity and selectivity in 5 sets of tests.

Embodiment 2

[0028] The reacted mixture was filtered through filter paper to separate the Pd@CN catalyst and solution. Put 6.4g of the recovered Pd@CN catalyst into a 200mL beaker, add 128mL of deionized water, and stir at 60°C for 10min at a stirring rate of 100r / min. Filtrate while it is hot, the filtration temperature is controlled at 50°C, and the washed Pd@CN catalyst is recovered. Repeat the above washing step twice. The Pd@CN catalyst washed twice was soaked in 64 mL deionized water.

[0029] The Pd@CN catalyst washed twice was added to the reactor together with 64 mL of deionized water for the experiment of hydrogenation of phenol to cyclohexanone, and the reaction was stopped after 2 hours. Through 5 repeated experiments, the catalytic activity decreased by 8.2%.

Embodiment 3

[0031] The reacted mixture was filtered through filter paper to separate the Pd@CN catalyst and solution. Put 6.4g of the recovered Pd@CN catalyst into a 2000mL beaker, add 950mL of deionized water, and stir at 90°C for 1h at a stirring rate of 500r / min. Filtrate while it is hot, the filtration temperature is controlled at 90°C, and the washed Pd@CN catalyst is recovered. Repeat the above washing steps five times. The Pd@CN catalyst washed five times was soaked in 640 mL deionized water.

[0032] The Pd@CN catalyst washed five times was added to the reactor together with 640 mL of deionized water for the experiment of hydrogenation of phenol to cyclohexanone, and the reaction was stopped after 2 hours. Through 5 repeated experiments, the catalytic activity decreased by 3.6%.

technical field

[0001] The invention relates to a post-treatment method of a phenol hydrogenation Pd@CN catalyst, in particular to a post-treatment method of a Pd@CN catalyst used in a hydrogenation process, and belongs to the technical field of catalysis. Background technique

[0002] Cyclohexanone is an important organic chemical raw material, mainly used in the production of caprolactam and adipic acid. In industry, it is mainly produced by cyclohexane oxidation. However, cyclohexane oxidation needs to be carried out under high temperature and high pressure, and many by-products will be generated, causing serious environmental pollution. At present, the one-step hydrogenation of phenol to cyclohexanone has attracted widespread attention due to its environmental friendliness and low energy consumption.

[0003] The reaction mechanism of one-step hydrogenation of phenol to cyclohexanone is as follows: phenol chemically adsorbs on the surface of the carrier, and reacts wit...

Examples

Embodiment 1

[0025] The reacted mixture was filtered through filter paper to separate the Pd@CN catalyst and solution. Put 6.4g of the recovered Pd@CN catalyst into a 1000mL beaker, add 500mL of deionized water, and stir at 70°C for 30min at a stirring rate of 400r / min. Filtrate while it is hot, the filtration temperature is controlled at 60°C, and the washed Pd@CN catalyst is recovered. Repeat the above washing steps three times. The Pd@CN catalyst washed three times was soaked in 200 mL deionized water.

[0026] The Pd@CN catalyst washed three times was added to the reactor together with 200mL deionized water, and used in the experiment of hydrogenation of phenol to cyclohexanone. The reaction was stopped after 2 hours, and it was recycled 5 times under the subsequent treatment method. The results are as follows figure 2 shown. The Pd@CN catalyst maintained good catalytic activity and selectivity in 5 sets of tests.

Embodiment 2

[0028] The reacted mixture was filtered through filter paper to separate the Pd@CN catalyst and solution. Put 6.4g of the recovered Pd@CN catalyst into a 200mL beaker, add 128mL of deionized water, and stir at 60°C for 10min at a stirring rate of 100r / min. Filtrate while it is hot, the filtration temperature is controlled at 50°C, and the washed Pd@CN catalyst is recovered. Repeat the above washing step twice. The Pd@CN catalyst washed twice was soaked in 64 mL deionized water.

[0029] The Pd@CN catalyst washed twice was added to the reactor together with 64 mL of deionized water for the experiment of hydrogenation of phenol to cyclohexanone, and the reaction was stopped after 2 hours. Through 5 repeated experiments, the catalytic activity decreased by 8.2%.

Embodiment 3

[0031] The reacted mixture was filtered through filter paper to separate the Pd@CN catalyst and solution. Put 6.4g of the recovered Pd@CN catalyst into a 2000mL beaker, add 950mL of deionized water, and stir at 90°C for 1h at a stirring rate of 500r / min. Filtrate while it is hot, the filtration temperature is controlled at 90°C, and the washed Pd@CN catalyst is recovered. Repeat the above washing steps five times. The Pd@CN catalyst washed five times was soaked in 640 mL deionized water.

[0032] The Pd@CN catalyst washed five times was added to the reactor together with 640 mL of deionized water for the experiment of hydrogenation of phenol to cyclohexanone, and the reaction was stopped after 2 hours. Through 5 repeated experiments, the catalytic activity decreased by 3.6%.

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