CN107473936B - A kind of method for preparing lower alkanol from diol compound - Google Patents

Abstract

The invention belongs to the technical field of organic compound preparation, and discloses a method for preparing lower alkanols from glycol compounds. Lower alkanols can be obtained by reacting at 160～220℃ for 6～24h. The catalyst used in the invention is a nano-nickel catalyst, the raw materials are readily available, and the cost is low; the catalyst is simple to prepare and can be reused; the reaction system uses water as a solvent, and does not need to introduce hydrogen. The reaction conditions of the invention are mild, the equipment requirements are low, only a sealed reaction kettle is needed, the equipment is simple, the operation is easy, and the yield of the corresponding lower alkanol (1,2-propylene glycol to prepare ethanol) can reach up to 65% , with good industrialization prospects.

Description

A kind of method for preparing lower alkanol from diol compound

technical field

The invention belongs to the technical field of organic preparation, and in particular relates to a method for preparing lower alkanols from diol compounds.

Background technique

In recent years, the use of chemical or biological methods to convert biomass derivatives glycol compounds (ethylene glycol, 1,2-propanediol, 1,2-butanediol, etc.) into fuels has been widely studied and developed worldwide. and other high value-added chemicals. Among them, the conversion of glycol compounds into lower alcohols (methanol, ethanol, butanol) is another trend in the conversion and utilization of such compounds, which has attracted much attention. Since lower alcohols (methanol, ethanol, butanol) can be directly applied to power fuels, this synthesis route can not only improve the flammability of biomass derivatives, but also improve the application range of biomass derivatives. Diols contain carbon-oxygen and carbon-carbon, in which the carbon-oxygen bond is easier to break, but it is difficult to selectively realize the cleavage of carbon-carbon bond to prepare lower alkanols. Because in the field of organic chemistry, non-polar carbon-carbon bonds are very thermodynamically stable, their HOMO energy is too low, and their LUMO energy is too high to combine with catalysts, so carbon-carbon bonds will remain stable in many organic reactions, so Diols are used to prepare lower alkanols. At present, the main problem of carbon-carbon bond cleavage is: the complexity of the reaction substrate, which is not universal. The catalyst has complex synthesis, harsh reaction conditions and low selectivity to lower alcohols. There is also an important problem that the conversion of diols into lower alcohols requires the introduction of a large amount of hydrogen and toxic chemical solvents.

To sum up, the problems existing in the prior art are: in the process of preparing lower alkanols from diol compounds, the catalyst used is complicated to prepare, and the introduction of high-pressure hydrogen is dangerous and toxic organic solvents are used; In the process of synthesizing lower alkanols, the selectivity is low, and there are problems such as easy formation of ether compounds, difficult operation process and high cost.

SUMMARY OF THE INVENTION

In view of the problems existing in the prior art, the present invention provides a method for preparing lower alkanols from diol compounds.

The present invention is achieved in this way, a method for preparing lower alkanols from glycol compounds, the method for preparing lower alkanols from glycol compounds, without introducing hydrogen, with glycol compounds and water As raw material, with nano-nickel as catalyst, the glycol compound, water and nano-nickel are put into the autoclave and sealed under the saturated steam pressure of water (0.6-2.3Mpa) to undergo hydrothermal reaction, and the reaction is carried out at 160 ℃～ The reaction was carried out at 220°C for 6h-30h, and after cooling, the solution was filtered to obtain a lower alkanol solution.

Further, the chemical reaction formula of the method for preparing lower alkanol by diol compound is:

Further, the diol compounds are 1,2-propanediol, 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,3-propanediol and 1,2-butanediol One of the dienols.

Further, the lower alkanols after the reaction are: 1,2-propanediol corresponds to ethanol; 1,2-butanediol corresponds to n-propanol; 1,2-pentanediol corresponds to n-butanol; Hexylene glycol corresponds to n-pentanol; 1,3-propanediol corresponds to ethanol; 1,2-butadienol corresponds to n-propanol.

Further, in the diol compound and water as raw materials, the aqueous solution of the diol compound is: 25ml, 0.05mol/L of the diol compound aqueous solution; the nano nickel is: 0.05g～0.5g.

Further, the nano-nickel catalyst is prepared by wet chemical reduction method, and the specific method includes:

4.27g of nickel chloride was dissolved in 300ml of water, under nitrogen atmosphere, 100ml of 1mol sodium borohydride aqueous solution was added dropwise, vigorously stirred for 3h to 5h, washed with water several times after the reaction, and dried in a vacuum drying box for 12h, A nano-nickel catalyst is obtained.

Another object of the present invention is to provide a lower alkanol prepared by utilizing the above-mentioned method for preparing lower alkanol from a diol compound.

Another object of the present invention is to provide a power fuel prepared by utilizing the above-mentioned lower alkanol.

The advantages and positive effects of the present invention are:

The present invention develops a new method, which can efficiently convert diols into diols through selective carbon-carbon bond cleavage through hydrothermal reaction without using high-pressure hydrogen using a simple amorphous nickel-based catalyst. lower alcohols. It provides a new idea for the activation of carbon-carbon bonds in organic reactions, especially the cleavage of carbon-carbon bonds.

The closest prior art to the present invention is a paper published in ACS Catal. 2012, 2, 1285-1289, entitled "Partial Deoxygenation of 1,2-Propanediol Catalyzed by Iridium PincerComplexes". Compared with this method, the advantages of the present invention are:

The catalyst used in the invention is a nano-nickel catalyst, the raw materials are readily available, and the cost is low; the catalyst is simple to prepare and can be reused; the reaction system uses water as a solvent, and does not need to introduce hydrogen. The reaction conditions of the invention are mild, the equipment requirements are low, only a sealed reaction kettle is needed, the equipment is simple, the operation is easy, and the yield of the corresponding lower alkanol (1,2-propanediol to prepare ethanol) can reach up to 65% , with good industrialization prospects.

Description of drawings

1 is a flow chart of a method for preparing lower alkanols from diol compounds provided in an embodiment of the present invention.

FIG. 2 is a mass spectrum of the product ethanol in Examples 1 and 18 provided in the embodiment of the present invention.

Fig. 3 is the mass spectrum of the product n-propanol in Examples 14 and 17 provided by the embodiment of the present invention.

Fig. 4 is the mass spectrum of the product n-butanol in Example 15 provided by the embodiment of the present invention.

Fig. 5 is the mass spectrum of the product n-amyl alcohol in Example 16 provided by the embodiment of the present invention.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

In the prior art, the catalyst used is complicated to prepare, and the introduction of high-pressure hydrogen has certain dangers and toxic dioxane is used as a solvent; the synthetic n-propanol is easy to form ether compounds, and the operation process is difficult , the problem of high cost.

Based on this theory, the present invention develops a new method to efficiently convert diols into lower alcohols through selective carbon-carbon bond cleavage using a simple amorphous nickel-based catalyst under hydrothermal conditions. It provides a new idea for the activation of carbon-carbon bonds in organic reactions, especially the cleavage of carbon-carbon bonds.

The application principle of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in Figure 1, the method for preparing lower alkanol from diol compounds provided in the embodiment of the present invention comprises:

S101: put a certain amount of glycol compounds, a certain amount of water and nano-nickel into the autoclave, and mix them uniformly.

S102: After sealing, react at 160-220° C. for 6-24 hours, and obtain a lower alkanol solution after cooling.

As a preferred solution in the embodiment of the present invention, the diol compounds are 1,2-propanediol, 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,3 - Propylene glycol, 1,2-butadienol.

The main product after the reaction is that 1,2-propanediol corresponds to ethanol, 1,2-butanediol corresponds to n-propanol, 1,2-pentanediol corresponds to n-butanol, and 1,2-hexanediol corresponds to is n-pentanol, 1,3-propanediol corresponds to ethanol, and 1,2-butadienol corresponds to n-propanol.

Described nanometer nickel catalyst adopts wet chemical reduction method to make, and concrete method is as follows:

4.27g of nickel chloride was dissolved in 300ml of water, under nitrogen atmosphere, 100ml of 1mol sodium borohydride aqueous solution was added dropwise, vigorously stirred for 3h to 5h, washed with water several times after the reaction, and dried in a vacuum drying box for 12h, A nano-nickel catalyst is obtained.

As a preferred solution of the embodiment of the present invention, the preferred condition is that the reaction is carried out at 160-220° C. for 6-30 hours.

As a preferred solution of the embodiment of the present invention, the preferred amount of the catalyst is 0.05-0.5 g.

The application principle of the present invention will be further described below with reference to specific embodiments.

Example 1

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.2g of nano-nickel prepared by reduction of sodium borohydride into a 30mL autoclave, and after sealing the reactor, react at 200°C for 24h, After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). From the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 48%.

Example 2

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.2g of nano-nickel prepared by sodium borohydride reduction into a 30mL autoclave, and after sealing the reactor, react at 220°C for 24h, After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). From the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 43%.

Example 3

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.2g of nano-nickel prepared by reduction of sodium borohydride into a 30mL autoclave, and after sealing the reactor, react at 180°C for 24h, After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). Based on the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 46%.

Example 4

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.2g of nano-nickel prepared by sodium borohydride reduction into an autoclave with a volume of 30mL. After sealing the reactor, react at 160°C for 24h. After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). According to the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product can be calculated to be 35%.

Example 5

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.05g of nano-nickel prepared by reduction of sodium borohydride into an autoclave with a volume of 30mL. After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). From the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 15%.

Example 6

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.05g of nano-nickel prepared by reduction of sodium borohydride into an autoclave with a volume of 30mL. After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). According to the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product can be calculated to be 20%.

Example 7

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.1g of nano-nickel prepared by reduction of sodium borohydride into a 30mL autoclave, and after sealing the reactor, react at 200°C for 24h, After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). From the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 42%.

Example 8

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.3g of nano-nickel prepared by reduction of sodium borohydride into an autoclave with a volume of 30mL, after sealing the reactor, react at 200°C for 24h, After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). From the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 47%.

Example 9

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.4g of nano-nickel prepared by reduction of sodium borohydride into an autoclave with a volume of 30mL. After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). Based on the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 46%.

Example 10

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.5g of nano-nickel prepared by reduction of sodium borohydride into an autoclave with a volume of 30mL. After sealing the reactor, react at 200°C for 24h. After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). Based on the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 45%.

Example 11

Put 25ml of 0.05mol/L 1,2-propanediol aqueous solution and 0.5g of nano-nickel prepared by reduction of sodium borohydride into a 30mL autoclave, and after sealing the reactor, react at 200°C for 30h, After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). From the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 47%.

Example 12

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.2g of nano-nickel prepared by reduction of sodium borohydride into an autoclave with a volume of 30mL. After sealing the reactor, react at 200°C for 6h. After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). From the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product can be calculated to be 5%.

Example 13

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.2g of nano-nickel prepared by reduction of sodium borohydride into a 30mL autoclave, and after sealing the reactor, react at 200°C for 12h, After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). From the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 31%.

Example 14

Put 25ml of 0.05mol/L aqueous solution of 1,2-propanediol and 0.5g of nano-nickel prepared by sodium borohydride reduction into an autoclave with a volume of 30mL. After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). From the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 43%.

Example 15

Put 25ml of 0.05mol/L 1,2-propanediol aqueous solution and 0.5g of nano-nickel prepared by reduction of sodium borohydride into a 30mL autoclave, and after sealing the reactor, react at 200°C for 30h, After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). Based on the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 46%.

Example 16

The aqueous solution of the 1,2-butanediol of 0.05mol/L of 25ml and the nano-nickel 0.2g prepared by the reduction of sodium borohydride are put into the autoclave with a volume of 30mL, and after the closed reactor, react at 200°C 24h, after the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). According to the concentration-peak area standard curve and the product peak area, the molar yield of n-propanol in the product can be calculated to be 42%.

Example 17

The aqueous solution of the 1,2-pentanediol of 0.05mol/L of 25ml and the nano-nickel 0.2g prepared by the reduction of sodium borohydride are put into the autoclave with a volume of 30mL, and after the closed reactor, react at 200°C 24h, after the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). According to the concentration-peak area standard curve and the product peak area, the molar yield of n-butanol in the product can be calculated to be 50%.

Example 18

The aqueous solution of the 1,2-hexanediol of 0.05mol/L of 25ml and the nano-nickel 0.2g prepared by the reduction of sodium borohydride are put into the autoclave with a volume of 30mL, after sealing the reactor, react at 200°C 24h, after the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). According to the concentration-peak area standard curve and the product peak area, the molar yield of n-amyl alcohol in the product can be calculated to be 50%.

Example 19

The aqueous solution of 25ml of 0.05mol/L 1,2-butadienol and 0.2g of nano-nickel prepared by sodium borohydride reduction were put into the autoclave with a volume of 30mL, after the closed reaction kettle, at 200°C The reaction was carried out for 24h, and after the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). According to the concentration-peak area standard curve and the product peak area, the molar yield of n-propanol in the product can be calculated to be 32%.

Example 20

Put 25ml of 0.05mol/L aqueous solution of 1,3-propanediol and 0.2g of nano-nickel prepared by reduction of sodium borohydride into an autoclave with a volume of 30mL. After the reaction kettle was cooled, the reaction solution was tested.

The resulting solution was detected by gas chromatography-mass spectrometry (TRACE DSQ GC-MS). Based on the concentration-peak area standard curve and the product peak area, the molar yield of ethanol in the product was calculated to be 25%.

FIG. 2 is a mass spectrum of the product ethanol in Examples 1 and 18 provided in the embodiment of the present invention.

Fig. 3 is the mass spectrum of the product n-propanol in Examples 14 and 17 provided by the embodiment of the present invention.

Fig. 4 is the mass spectrum of the product n-butanol in Example 15 provided by the embodiment of the present invention.

Fig. 5 is the mass spectrum of the product n-amyl alcohol in Example 16 provided by the embodiment of the present invention.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (5)

1. A process for producing a lower alkanol from a diol compound, comprising charging the diol compound, water and nano nickel into a high-pressure reactor using the diol compound and water as raw materials and nano nickel as a catalyst, sealing the reactor, carrying out a hydrothermal reaction, reacting the reaction product at 160 to 220 ℃ for 6 to 30 hours, cooling the reaction product, and filtering the reaction product to obtain a lower alkanol solution; the lower alkanol is ethanol, n-propanol, n-butanol or n-pentanol;

in the raw materials of the diol compound and water, the aqueous solution of the diol compound is as follows: 25ml of 0.05mol/L aqueous solution of diol compound; the nano nickel is as follows: 0.1g or 0.3-0.5 g.

2. The process for producing a lower alkanol from a diol compound according to claim 1, wherein the process for producing a lower alkanol from a diol compound has the chemical reaction formula:

3. the process for producing a lower alkanol from a diol compound according to claim 1,

the diol compound is one of 1, 2-propylene glycol, 1, 2-butanediol, 1, 2-pentanediol, 1, 2-hexanediol, 1, 3-propylene glycol and 1, 2-butadienol.

4. The process for producing a lower alkanol from a diol compound according to any one of claims 1 to 3, wherein the lower alkanol after the reaction is: 1,2-propanediol corresponds to ethanol; 1, 2-butanediol corresponds to n-propanol; the 1, 2-pentanediol corresponds to n-butanol; 1, 2-hexanediol corresponds to n-pentanol; 1, 3-propanediol corresponds to ethanol; 1, 2-butadienol corresponds to n-propanol.

5. The method of claim 1, wherein the nano nickel catalyst is prepared by wet chemical reduction, and the method comprises:

dissolving 4.27g of nickel chloride in 300ml of water, dropwise adding 100ml of 1mol of sodium borohydride aqueous solution under the nitrogen atmosphere, violently stirring for 3-5 h, washing with water for several times after the reaction is finished, and drying in a vacuum drying oven for 12h to obtain the nano nickel catalyst.

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