Method for producing decanal

文档序号：644576 发布日期：2021-05-14 浏览：85次中文

阅读说明：本技术 制备癸醛的方法 (Method for producing decanal ) 是由陈勇鲁树亮徐洋吴佳佳郝雪松于 2019-10-28 设计创作，主要内容包括：本发明属于催化加氢技术领域,涉及一种制备癸醛的方法。该方法包括以下步骤：在氢气存在下,使复合催化剂、癸烯醛和有机溶剂接触进行反应,得到含有癸醛的产物；所述复合催化剂包含多元酸交联的高分子基体和金属活性组分,所述高分子基体为含有含氮杂环侧基的高分子聚合物,所述含氮杂环侧基中的氮原子具有孤对电子,能够通过配位键牢固的负载金属活性组分。本发明提供的制备癸醛的方法能够提高癸烯醛加氢生成癸醛的选择性,抑制癸醇的生成,并且该方法所使用的催化剂成本低,反应温度低。(The invention belongs to the technical field of catalytic hydrogenation, and relates to a method for preparing decanal. The method comprises the following steps: in the presence of hydrogen, enabling the composite catalyst, decenal and an organic solvent to contact and react to obtain a product containing decenal; the composite catalyst comprises a polyacid crosslinked polymer matrix and a metal active component, wherein the polymer matrix is a polymer containing a nitrogen-containing heterocyclic side group, and a nitrogen atom in the nitrogen-containing heterocyclic side group has lone pair electrons and can firmly support the metal active component through a coordination bond. The method for preparing the decanal can improve the selectivity of the decenal hydrogenation to the decanal and inhibit the generation of decanol, and the catalyst used by the method has low cost and low reaction temperature.)

1. A process for preparing decanal, the process comprising the steps of:

in the presence of hydrogen, enabling the composite catalyst, decenal and an organic solvent to contact and react to obtain a product containing decenal;

the composite catalyst comprises a polyacid crosslinked polymer matrix and a metal active component, wherein the polymer matrix is a high-molecular polymer containing a nitrogen-containing heterocyclic side group, a nitrogen atom in the nitrogen-containing heterocyclic side group has a lone pair of electrons, and at least part of the metal active component and the lone pair of electrons of the nitrogen atom form a coordination bond.

2. The method according to claim 1, wherein the polyacid crosslinked polymeric matrix is obtained by coordination crosslinking of a polymeric matrix with a polyacid.

3. The process of claim 1, wherein the polyacid is peroxymolybdic acid.

4. The method of claim 1, wherein the pendant nitrogen-containing heterocyclic group is an imidazolyl group and/or a pyridyl group;

preferably, the polymeric monomer of the polymer matrix includes C containing imidazolyl and/or pyridyl₂～C₆An olefin.

5. The method of claim 1, wherein the molar ratio of the polyacid to the pendant nitrogen-containing heterocyclic group is 1 (4-20).

6. The method according to claim 1, wherein the metal active component comprises palladium derived from palladium nitrate and/or palladium chloride, preferably palladium nitrate.

7. The method of claim 6, wherein the palladium is present in the composite catalyst in an amount of 0.1 to 1 wt%.

8. The process according to claim 1, wherein the temperature of the reaction is between 40 ℃ and 100 ℃; the pressure is 1-4 MPa; the time is 1-10 hours;

preferably, the organic solvent is C₁～C₄A saturated monohydric alcohol of (1).

9. The method of claim 1, wherein the composite catalyst is prepared by:

a. dissolving or dispersing the polymer matrix in methanol and/or ethanol to obtain a first solution;

b. dissolving the polybasic acid in methanol and/or ethanol to obtain a second solution;

c. adding the second solution dropwise into the first solution under stirring to generate a first precipitate;

d. c, separating the first precipitate generated in the step c to obtain a solid substance;

e. dissolving the salt of the metal active component in methanol and/or ethanol to obtain a third solution;

f. re-dispersing the solid material obtained in step d in methanol and/or ethanol to obtain a fourth solution; adding the third solution dropwise into the fourth solution under stirring to generate a second precipitate;

g. and f, separating the second precipitate generated in the step f to obtain the composite catalyst.

10. The method according to claim 9, wherein in the step a, the mass concentration of the polymeric monomer of the polymer matrix in the first solution is 0.01-1 mmol/mL; preferably 0.1-0.5 mmol/mL;

in the step b, the mass concentration of the polybasic acid in the second solution is 0.01-1 mmol/mL; preferably 0.1-0.5 mmol/mL;

in the step e, the mass concentration of the salt of the metal active component in the third solution is 0.01-1 mg/mL; preferably 0.05-0.5 mg/mL;

in the step f, the mass concentration of solid matters in the fourth solution is 0.05-0.2 g/mL; preferably 0.1 to 0.2 g/mL.

Technical Field

The invention belongs to the technical field of catalytic hydrogenation, and particularly relates to a method for preparing decanal.

Background

Decanal is an important organic raw material and spice, naturally exists in citrus, lemon, grapefruit, tomato, strawberry and other fruits, and can be used for preparing edible essence of orange, citrus and lemon. Because the extraction cost of the decanal from natural plants is high and the yield is low, the decanal is mostly prepared by industrial synthesis.

The existing routes for producing decanal mainly include: (1) olefin of C9 is obtained through trimerization of propylene or oligomerization cutting of propylene and butylene, and decanal is generated through oxo synthesis and hydrogenation; (2) the method comprises the steps of synthesizing valeraldehyde through butene hydroformylation, then generating decenal through condensation, and generating decanal through hydrogenation.

Currently, much research has focused on the hydrogenation of decenal to produce decanol. For example, patent document CN101185893A discloses a catalyst for preparing isodecyl alcohol by gas phase hydrogenation of decenal and a preparation method thereof. The catalyst is prepared by a coprecipitation method and consists of copper oxide, zinc oxide, aluminum oxide and an active assistant; the active auxiliary agent is one or more of metal elements of Na, K, Ni, Co, Mg, Ca and Ba; the mol contents of copper oxide, zinc oxide and aluminum oxide are respectively 20-70%, 28-70% and 1-10%, and the active auxiliary agent is present in the mol content of 0.1-2.0%. The catalyst is used for preparing isodecyl alcohol by the gas-phase hydrogenation of decenal, and has higher decenal conversion rate and isodecyl alcohol selectivity.

Patent document CN102666455A is a process for preparing decanol by hydrogenating decenal. The process requires at least two reactors, wherein the first reactor uses a copper-based and/or nickel-based catalyst and the second reactor uses a palladium or ruthenium catalyst, both carried out on a solid catalyst in the liquid phase. The process enables high-yield hydrogenation of decenal to decanol, the unsaturated decenal content in the hydrogenated output being less than 1500 ppm.

Patent document CN107876047A discloses a preparation method of Pd/C catalyst for alpha, beta-unsaturated aldehyde/ketone hydrogenationThe method is carried out. The Pd/C catalyst consists of an active carbon carrier and metal Pd, wherein the average particle size of the active carbon carrier is 27 mu m, and the specific surface area is 1400m²(ii)/g, wherein the specific surface area of pores smaller than 2nm accounts for 6% of the total specific surface area; the load capacity of the metal Pd is 3-5% of the mass of the Pd/C catalyst; the preparation method of the Pd/C catalyst comprises the following steps: step one, placing an activated carbon carrier in H₂O₂Uniformly mixing and stirring the mixture in the aqueous solution, heating and refluxing the mixture, and sequentially filtering, washing and drying the mixture to obtain a pretreated activated carbon carrier; step two, adding NaCl aqueous solution into H₂PdCl₄In an aqueous solution, 1mL of H₂PdCl₄The aqueous solution contains 0.05gPd, and Na is obtained by heating and evaporating water after uniform mixing₂PdCl₄Crystals of said Na₂PdCl₄Dissolving the crystal in deionized water to prepare a palladium precursor solution, wherein 1mL of the palladium precursor solution contains 0.01g of Pd; the concentration of the NaCl aqueous solution is 0.5 g/mL; the aqueous NaCl solution and H₂PdCl₄The volume ratio of the aqueous solution is 1: 2; step three, pulping the pretreated activated carbon carrier obtained in the step one by using deionized water, then sequentially adding a surfactant and a reducing agent, and mixing and stirring for 60min to obtain mixed slurry; step four, adjusting the pH value of the palladium precursor solution prepared in the step two to 3-5 by adopting an alkaline solution, and then slowly dripping the solution into the mixed slurry obtained in the step three to obtain a mixed solution; and step five, heating the mixed solution obtained in the step four to 60-90 ℃, adjusting the pH of the mixed solution to be more than 9 by adopting an alkaline solution, keeping the temperature and stirring for 60min, and sequentially filtering, washing and drying to obtain the Pd/C catalyst. The catalyst obtained by the preparation method can be applied to the selective hydrogenation of unsaturated aldehyde/ketone to prepare saturated aldehyde/ketone.

Patent document CN108435167A discloses a Pd-Ag bimetallic catalyst for catalyzing hydrogenation of cinnamaldehyde, and a preparation method and application thereof. The carrier of the Pd-Ag bimetallic catalyst for catalyzing hydrogenation of cinnamaldehyde is a porous material; the mass percentage of the metal palladium relative to the carrier is 0.1-5%; the mass percentage of Ag is 0.1-0.5%. The porous material is MCM-41, SiO₂SBA-15 or activated carbon. Pd-Ag in a certain proportion of the catalyst can form an alloy which is loaded on MCM-41, SiO₂The palladium silver on the SBA-15 or the activated carbon is nano particles, the particle size is fine and uniform, and the palladium silver is highly distributed on the carrier; the method has high selectivity and stability for preparing the phenylpropyl aldehyde by selectively hydrogenating the carbon-carbon double bond of the cinnamaldehyde.

As can be seen from the above patent documents and paper documents, the noble metal palladium is a noble metal hydrogenation active component commonly used in industry, and has excellent selective hydrogenation activity due to its special valence electron structure, and is widely used in selective hydrogenation.

However, few studies have been reported on the selective hydrogenation of liquid-phase decenal to produce decanal. Li newly reported Pt/Al₂O₃2-propyl heptanal (Pt/Al) prepared by selective hydrogenation of 2-propyl-2-heptenal under catalysis of catalyst₂O₃The catalyst catalyzes the selective hydrogenation of 2-propyl-2-heptenal, Lixin, the development of fine petrochemical engineering, Vol 5, No. 2 in 2004, pp 30-32). The catalyst used in the method is Pt/Al produced by Engehard company₂O₃The catalyst is used, the platinum loading amount is 0.5%, the reaction temperature is 373-433K, the reaction pressure is 0.5-3.0 MPa, the conversion rate of the 2-propyl-2-heptenal can reach 93% at most, and the selectivity of the 2-propyl heptenal can reach 96% at most. Although the method described in the document has high conversion rate of decenal and selectivity of decenal, the active component of the catalyst required by the reaction is mainly Pt, and the catalyst is imported abroad, so that the cost is high, and the temperature required by the reaction is above 100 ℃, so that the energy consumption is high.

Therefore, there is a need for a relatively inexpensive and low energy consuming process for preparing decanal.

Disclosure of Invention

The invention aims to provide a method for preparing decanal, so as to reduce the cost and energy consumption for preparing the decanal.

In order to achieve the above object, the present invention provides a method for preparing decanal, comprising the steps of:

in the presence of hydrogen, enabling the composite catalyst, decenal and an organic solvent to contact and react to obtain a product containing decenal;

the composite catalyst comprises a polyacid crosslinked polymer matrix and a metal active component, wherein the polymer matrix is a polymer containing a nitrogen-containing heterocyclic side group, a nitrogen atom in the nitrogen-containing heterocyclic side group has a lone pair of electrons, and at least part of the metal active component and the lone pair of electrons of the nitrogen atom form a coordination bond.

It will be understood by those skilled in the art that the method for preparing decanal can be carried out in a reaction vessel with stirring function, which is preferably provided with stirring function, to achieve sufficient mixing contact between the raw materials and the catalyst, and to rapidly and sufficiently perform the hydrogenation reaction. The hydrogenation reaction is usually carried out in the absence of oxygen, and therefore, before the hydrogenation reaction is carried out, oxygen in the reaction vessel is first removed with hydrogen to reduce the formation of by-products.

Specifically, the polyacid crosslinked polymer matrix is obtained by the coordination crosslinking action of the polyacid on the polymer matrix. The polyacid crosslinked polymer matrix has stable pores and large specific surface area.

In the invention, nitrogen atoms in a polymer matrix of the composite catalyst have uncoordinated lone-pair electrons, and have coordination with the metal active component, so that the load stability of the metal active component is improved through the chemical bond effect. The nitrogen-containing heterocyclic side group contains a nitrogen atom with a lone pair of electrons, so that the purpose can be achieved. Preferably, the pendant group of the nitrogen-containing heterocycle is imidazolyl and/or pyridyl, that is, the polymer matrix is a polymer containing imidazolyl and/or pyridyl.

In the present invention, the main chain structure of the polymer matrix is not particularly limited, and it is preferable that the polymer monomer of the polymer matrix includes C containing an imidazole group and/or a pyridine group in view of the sufficiency of the site of the metal active component and steric hindrance of the group₂～C₆Olefin, the polymer matrix may be a homopolymer or a multipolymer, as long as the polymerized monomer contains C containing imidazolyl and/or pyridyl₂-C₆An olefin. What is needed isExamples of such homopolymers include, but are not limited to, polyvinylimidazole, polyvinylpyridine. Examples of such multipolymers include, but are not limited to, copolymers of vinylimidazole and divinylbenzene, copolymers of vinylpyridine and divinylbenzene, copolymers of vinylimidazole and vinylimine, and the like.

In a preferred embodiment of the invention, the molar ratio of the polybasic acid to the nitrogen-containing heterocyclic side group is 1 (4-20).

In a preferred embodiment of the present invention, the palladium content in the composite catalyst is 0.1 wt% to 1 wt%.

In a preferred embodiment of the present invention, the metal active component comprises palladium. The palladium is derived from a palladium salt, such as palladium nitrate and/or palladium chloride, preferably palladium nitrate.

In a specific embodiment of the present invention, the temperature is 40 to 100 ℃, for example 40 ℃, 60 ℃, 90 ℃, 100 ℃; the pressure is 1 to 4MPa, such as 1MPa, 1.5MPa, 2MPa, 2.5MPa, 3MPa, 3.5MPa, 4 MPa; the time is 1 to 10 hours, such as 2 to 8 hours, 4 to 6 hours.

In the invention, the preparation of the decanal by hydrogenation of the decenal is an exothermic reaction, and the raw materials are diluted by the organic solvent, so that the reaction temperature can be controlled, and the reaction process can be controlled. As long as the organic solvent does not react with decenal and hydrogen and does not react with itself, specifically, C₁-C₄A saturated monohydric alcohol of (1). C₁～C₄The saturated monohydric alcohol comprises at least one of methanol, ethanol, propanol, n-butanol and isobutanol.

In the invention, the composite catalyst is prepared by the following steps:

a. dissolving or dispersing the polymer matrix in methanol and/or ethanol to obtain a first solution;

b. dissolving the polybasic acid in methanol and/or ethanol to obtain a second solution;

c. adding the second solution dropwise into the first solution under stirring to generate a first precipitate;

d. c, separating the first precipitate generated in the step c to obtain a solid substance;

e. dissolving the salt of the metal active component in methanol and/or ethanol to obtain a third solution;

g. and f, separating the second precipitate generated in the step f to obtain the composite catalyst.

In one embodiment of the present invention, the salt of the metal active component comprises: at least one of palladium nitrate, palladium chloride, palladium acetate and chloropalladic acid.

In the present invention, a person skilled in the art can empirically determine the concentration of the polymer matrix in the first solution, the concentration of the polyacid in the second solution, the concentration of the salt of the metal active component in the third solution, and the concentration of the solid substance in the fourth solution, and the present invention is not particularly limited as long as the composite catalyst can be prepared.

Specifically, in the step a, the mass concentration of the polymeric monomer of the polymer matrix in the first solution is 0.01-1 mmol/mL; preferably 0.1-0.5 mmol/mL;

in the step b, the mass concentration of the polybasic acid in the second solution is 0.01-1 mmol/mL; preferably 0.1-0.5 mmol/mL;

in the step e, the mass concentration of the salt of the metal active component in the third solution is 0.01-1 mg/mL; preferably 0.05-0.5 mg/mL;

in the step f, the mass concentration of solid matters in the fourth solution is 0.05-0.2 g/mL; preferably 0.1 to 0.2 g/mL.

In the above steps d and g, the separation can be various separation methods conventional in the art, such as vacuum filtration, and after the separation, a washing step is preferably performed, and in the step g, after the washing, a drying step is preferably further included, and the drying condition is, for example, 60-100 ℃ for 6-10 h.

According to the method for preparing the decanal, since the nitrogen atoms in the polymer matrix of the composite catalyst have uncoordinated lone-pair electrons, at least part of the metal active components and the lone-pair electrons of the nitrogen atoms form coordinate bonds, the load stability of the metal active components is improved, the dispersity of the metal active components is improved, the electron distribution of the outermost layer of the metal active components is changed, the hydrogenation activity of the metal active components on C ═ O is inhibited, the selectivity of decanal generated by hydrogenating decenal is improved, the generation of decanol is inhibited, and the catalyst used in the method is low in cost and low in reaction temperature.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Detailed Description

Preferred embodiments of the present invention will be described in more detail below. While the following describes preferred embodiments of the present invention, it should be understood that the present invention may be embodied in various forms and should not be limited by the embodiments set forth herein.

Preparation example 1

The preparation example provides a composite catalyst.

(1) 3g (0.03mol) of Polyvinylimidazole (PVIM) were weighed out and dissolved in 200ml of methanol, and 50ml of a 0.1mmol/ml methanol solution of peroxomolybdic acid (homemade, commercially available molybdenum powder dissolved in 30% hydrogen peroxide) were added dropwise with stirring, and a solid material immediately appeared in the solution. After the addition was complete, stirring was maintained for 4 h. Finally, after vacuum filtration and methanol washing for 3 times, drying at 80 ℃ for 8 hours to obtain the peroxymolybdic acid-polyvinyl imidazole polymer, which is marked as PMo-1.

(2) 2g of PMo-1 prepared in preparation example 1 was weighed out and dispersed in 20ml of methanol, and 40ml of a methanol solution of palladium nitrate containing 0.5mg/ml of palladium was added dropwise with stirring. After the end of the dropwise addition, stirring was maintained for 4 h. And finally, after vacuum filtration and methanol washing for 3 times, drying at 80 ℃ for 8 hours to obtain the Pd-peroxymolybdic acid-polyvinyl imidazole composite catalyst with 1 percent of Pd loading, with the number of A1-1.

(3) A1-1 is shown in formula I.

Preparation example 2

The preparation example provides a composite catalyst.

(1) 2g of PMo-1 prepared in preparation example 1 was weighed out and dispersed in 20ml of methanol, and 40ml of a methanol solution of palladium nitrate containing 0.05mg/ml of palladium was added dropwise with stirring. After the end of the dropwise addition, stirring was maintained for 4 h. And finally, after vacuum filtration and methanol washing for 3 times, drying at 80 ℃ for 8 hours to obtain the Pd-peroxomolybdic acid-polyvinyl imidazole composite catalyst with the Pd loading of 0.1 percent, which is numbered A1-2.

(2) A1-2 is shown in formula I.

Preparation example 3

The preparation example provides a composite catalyst.

(1) 3.76g (0.04mol) of Polyvinylimidazole (PVIM) were weighed out and dissolved in 200ml of methanol, and 100ml of a 0.1mmol/ml methanol solution of peroxomolybdic acid (homemade, commercially available molybdenum powder dissolved in 30% hydrogen peroxide) were added dropwise with stirring, whereupon a solid material immediately appeared in the solution. After the addition was complete, stirring was maintained for 4 h. Finally, after vacuum filtration and methanol washing for 3 times, drying at 80 ℃ for 8 hours to obtain the peroxymolybdic acid-polyvinyl imidazole polymer, which is marked as PMo-2.

(2) 2g of PMo-2 prepared in preparation example 3 was weighed out and dispersed in 20ml of methanol, and 40ml of a methanol solution of palladium nitrate containing 0.5mg/ml of palladium was added dropwise with stirring. After the end of the dropwise addition, stirring was maintained for 4 h. And finally, after vacuum filtration and methanol washing for 3 times, drying at 80 ℃ for 8 hours to obtain the Pd-peroxymolybdic acid-polyvinyl imidazole composite catalyst with 1 percent of Pd loading, with the number of A2-1.

(3) A2-1 is shown in formula I.

Preparation example 4

The preparation example provides a composite catalyst.

(1) 2g of PMo-2 prepared in preparation example 3 was weighed out and dispersed in 20ml of methanol, and 40ml of a methanol solution of palladium nitrate containing 0.05mg/ml of palladium was added dropwise with stirring. After the end of the dropwise addition, stirring was maintained for 4 h. And finally, after vacuum filtration and methanol washing for 3 times, drying at 80 ℃ for 8 hours to obtain the Pd-peroxomolybdic acid-polyvinyl imidazole composite catalyst with the Pd loading of 0.1 percent, which is numbered A2-2.

(2) A2-2 is shown in formula I.

Preparation example 5

The preparation example provides a composite catalyst.

(1) 3.76g (0.04mol) of Polyvinylimidazole (PVIM) were weighed out and dissolved in 200ml of methanol, and 20ml of a 0.1mmol/ml methanol solution of peroxomolybdic acid (homemade, commercially available molybdenum powder dissolved in 30% hydrogen peroxide) were added dropwise with stirring, and a solid material immediately appeared in the solution. After the addition was complete, stirring was maintained for 4 h. Finally, after vacuum filtration and methanol washing for 3 times, drying at 80 ℃ for 8 hours to obtain the peroxymolybdic acid-polyvinyl imidazole polymer, which is marked as PMo-3.

(2) 2g of PMo-3 prepared in preparation example 5 was weighed out and dispersed in 20ml of methanol, and 40ml of a methanol solution of palladium nitrate containing 0.5mg/ml of palladium was added dropwise with stirring. After the end of the dropwise addition, stirring was maintained for 4 h. And finally, after vacuum filtration and methanol washing for 3 times, drying at 80 ℃ for 8 hours to obtain the Pd-peroxymolybdic acid-polyvinyl imidazole composite catalyst with 1 percent of Pd loading, with the number of A3-1.

(3) A3-1 is shown in formula I.

Preparation example 6

The preparation example provides a composite catalyst.

(1) 2g of PMo-3 prepared in preparation example 5 was weighed out and dispersed in 20ml of methanol, and 40ml of a methanol solution of palladium nitrate containing 0.05mg/ml of palladium was added dropwise with stirring. After the end of the dropwise addition, stirring was maintained for 4 h. And finally, after vacuum filtration and methanol washing for 3 times, drying at 80 ℃ for 8 hours to obtain the Pd-peroxomolybdic acid-polyvinyl imidazole composite catalyst with the Pd loading of 0.1 percent, which is numbered A3-2.

(2) A3-2 is shown in formula I.

Comparative example 1

This comparative example prepared a catalyst.

The traditional load type palladium hydrogenation catalyst Pd/Al is prepared by adopting an equivalent impregnation method₂O₃. 10ml of an aqueous palladium nitrate solution having a palladium concentration of 0.01g/ml was prepared, the pH of the solution was adjusted to 1 with nitric acid, 10g of alumina was added thereto, and after immersion for 2 hours, drying was carried out at 110 ℃ for 4 hours. Finally, the Pd/Al with the palladium loading of 1wt percent is prepared by roasting at 450 ℃ and reducing with hydrogen at 300 DEG C₂O₃Hydrogenation catalyst, noted as D-1.

Example 1