阅读说明：本技术 掺杂铁钼过渡金属的介孔硅催化剂绿色共氧制备己内酯 (Preparation of caprolactone by mesoporous silicon catalyst green oxygen-sharing doped with iron-molybdenum transition metal ) 是由 金鑫 赵磊 张春蓉 王东雪 马超 郑春明 于 2018-06-20 设计创作，主要内容包括：本发明涉及一种共氧催化制备己内酯的复合金属介孔硅催化剂制备方法。该该方法所制备的掺杂过渡金属钼和铁离子介孔硅催化剂。介孔具有较大的比表面积及可供大分子自由出入的多孔孔道,具有丰富的表面羟基及较高的水热稳定性,因此能保持载体的介孔结构和硅钨酸的Keggin型结构。采用了非均相介孔硅复合金属氧化物催化剂和空气中的氧气,更加易得,绿色环保,催化活性更高,并且过程中产生的过氧酸较少,只有10％左右,容易处理,总的操作较为简易,对于工业生产成本低,同时也可以使得该反应有极高的绿色性和酯或内酯的生成率,并且该反应也符合清洁生产和绿色化学的理念,也可以大大提高反应的原子经济性。(The invention relates to a preparation method of a composite metal mesoporous silicon catalyst for preparing caprolactone by using oxygen-sharing catalysis. The transition metal molybdenum and iron ion doped mesoporous silicon catalyst prepared by the method. The mesopores have larger specific surface area and porous channels for macromolecules to freely come in and go out, have rich surface hydroxyl groups and higher hydrothermal stability, so that the mesoporous structure of the carrier and the Keggin type structure of silicotungstic acid can be maintained. The heterogeneous mesoporous silicon composite metal oxide catalyst and oxygen in the air are adopted, the catalyst is easy to obtain, green and environment-friendly, the catalytic activity is higher, the amount of peroxy acid generated in the process is less, only about 10 percent, the treatment is easy, the total operation is simple, the cost for industrial production is low, the reaction has extremely high greenness and the generation rate of ester or lactone, the reaction also accords with the concepts of clean production and green chemistry, and the atom economy of the reaction can be greatly improved.)

1. A preparation method of a mesoporous silicon catalyst doped with iron-molybdenum transition metal as a catalyst comprises the following steps:

(1) dissolving 0.68-2.01 wt% of g P123 (123) in 30-50mL of concentrated hydrochloric acid of 36 wt% and 60.28-76.11 wt% of deionized water;

(2) stirring for 1 hour at the temperature of 50-70 ℃ at 300r/min, then violently stirring at 600r/min, slowly adding 5.24-6.83 wt% of TEOS, and finishing the adding for 15 min;

(3) after 5-10min, the rotating speed is slowed down to 300r/min, 0.07-0.21 wt% of ferric chloride and ammonium molybdate solid are added, 1.49-2.13 wt% of ammonium fluoride solid is added until the pH value is 8-10, and the stirring is continued for 6 hours;

(4) then the mixture is transferred into a reaction kettle for crystallization at the temperature of 100 ℃ and 150 ℃ for 12 hours, and then is cooled, filtered, washed and dried;

(5) finally, roasting for 6-8 hours in a muffle furnace at 500-600 ℃.

Technical Field

The invention relates to a preparation method of a catalyst for preparing epsilon-caprolactone by a Baeyer-Villiger (B-V) oxidation method, belonging to the fields of biomedical engineering and degradable plastics.

The mesoporous structure of the transition metal-doped mesoporous silicon material catalyst has larger specific surface area, porous channels for macromolecules to freely come in and go out, abundant surface hydroxyl groups and higher hydrothermal stability, so that the channel structure of a carrier and the Keggin type structure of silicotungstic acid can be maintained, and the effect of the catalyst and the recycling effect can be improved to a great extent.

Background

The epsilon-caprolactone is a novel polyester monomer, and the polyester has good biocompatibility and biodegradability and can be widely applied to biomedical engineering, degradable plastics and high value-added packaging materials; the poly-epsilon-caprolactone can also be copolymerized or blended and modified with various resins, so that various indexes of the resins are improved. With the improvement of environmental protection consciousness of people, the epsilon-caprolactone is expected to replace plastics to enter a wider market. However, the synthesis of the product involves severe technological operations such as strong oxidation, the purity requirement of the product is high, and the mature production technology is basically mastered in several companies in countries such as the United states, the United kingdom, the Japan and the like. In recent years, with the increasing use of epsilon-caprolactone, the market demand is gradually increased, and the production process is a new research hotspot.

At present, the production process of epsilon-caprolactone is mainly a Baeyer-Villiger (B-V) oxidation method, a peroxyacid method is used in the traditional epsilon-caprolactone production, but the peroxyacid has potential safety hazard in the transportation and storage processes, a large amount of waste acid is generated by reaction, and environmental pollution is easily caused; in addition, the reaction conditions of the biological oxidation method are mild, but the technology has high cost, poor stability and low efficiency, and some used bacterial strains are second pathogens and have higher environmental risks. Therefore, to achieve green oxidation one must start with green safe oxidants and catalysts to address the by-products.

The invention adopts the novel composite metal mesoporous material and air as reaction conditions, and can play a role in reducing environmental influence and improving preparation safety.

Disclosure of Invention

The invention aims to prepare caprolactone by taking mesoporous silicon catalyst doped with iron-molybdenum transition metal as catalyst for oxygen copolymerization

(1) Dissolving 0.68-2.01 wt% of gP123 in 21.88-39.04 wt% g of deionized water, 36 wt% of concentrated hydrochloric acid and 60.28-76.11 wt% of deionized water.

(2) Stirring at 50-70 ℃ for 1 hour at 300r/min, then stirring vigorously at 600r/min and slowly adding 5.24-6.83 wt% TEOS.

(3) And after 5-10min, the rotating speed is slowed down to 300r/min, 0.07-0.21 wt% of ferric chloride and ammonium molybdate solid are added, 1.49-2.13 wt% of ammonium fluoride solid is added until the pH value is 8-10, and the stirring is continued for 6 hours.

(4) And then the mixture is transferred into a reaction kettle for crystallization at the temperature of 100 ℃ and 150 ℃ for 12 hours, and then is cooled, filtered, washed and dried.

(5) And roasting the mixture in a muffle furnace at the temperature of 500 ℃ and 600 ℃ for 6 to 8 hours, and taking out the mixture.

The invention has the beneficial effects that: the composite metal oxide mesoporous material and the oxygen in the air are adopted, so that the composite metal oxide mesoporous material is easy to obtain and low in price, is green and environment-friendly, has high catalytic activity, generates less peroxy acid in the process, has low treatment cost, is easy to operate, has low industrial production cost, and can be widely applied.

The method for using the catalyst comprises the following steps:

(1) and adding 0.0025-0.0041 wt% g of catalyst into a three-neck flask.

(2) Taking 0.0238-0.0794 wt% of cyclohexanone, 0.0173-0.0510 wt% of benzaldehyde and taking 1, 2-dichloroethane as a solvent.

(3) Heating the solution to 40-60 ℃, rotating speed of 400-.

(4) Cooling for 10min, adding dodecane, centrifuging for 3min at 1000 r/min.

(5) And an internal standard method, taking supernatant liquid to measure the gas phase of the solution.

The invention has the beneficial effects that: the mesoporous catalyst doped with transition metal ions can enhance the electropositivity of carbonyl carbon on ketone, so that the electrophilicity of the carbonyl carbon is enhanced, an oxidant is favorably used for attacking the carbonyl carbon, the purpose of activating the carbonyl carbon can be achieved, oxygen in air is used as the catalyst to replace peroxy acid, the cost is reduced, and the process is cleaner and more green.

The present invention will be further described in detail with reference to the following examples for better understanding, but the scope of the present invention as claimed is not limited to the scope shown in the examples.

Detailed Description