Method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate

Abstract

The invention discloses a method for preparing ethanol and methanol through hydrogenation reduction of methyl acetate. The method comprises the following steps: taking a copper-loaded zinc oxide / carbon composite material as a catalyst, and introducing hydrogen into a reaction kettle to catalyze a hydrogenation reduction reaction of methyl acetate to prepare methanol and ethanol. The preparation method of the copper-loaded zinc oxide / carbon composite material comprises the following steps: S1, dissolving trimesic acid into N, N-dimethylacetamide, and then adding zinc nitrate for reaction; and S2, adding a product obtained after the reaction in the step S1 into a copper nitrate solution, stirring, standing, filtering and calcining to obtain the copper-loaded zinc oxide / carbon composite material. The copper-loaded zinc oxide / carbon composite material is used as a catalyst, so that the ethanol can be prepared by hydrogenation reduction of methyl acetate under low hydrogen pressure.

Description

Technical Field

[0001] The invention relates to the technical field of chemical industry, in particular to a method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate. Background Art

[0002] In industrial production, shell-and-tube reactors are often used for continuous operation. A large amount of hydrogen is introduced through a cyclic reaction to obtain ethanol and methanol, which can achieve catalytic hydrogenation reduction of esters. Currently, copper-based oxide materials are usually used as catalysts for hydrogenation reduction of methyl acetate. A large amount of hydrogen is usually introduced into a shell-and-tube reactor for reaction. There are safety hazards under high temperature and high pressure conditions. At the same time, the reaction conversion rate is affected during the recycling of materials, which is not conducive to energy saving, safety and environmental protection of production operations. Summary of the invention

[0003] Based on the technical problems existing in the background technology, the present invention proposes a method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate. Using a copper-loaded zinc oxide / carbon composite material as a catalyst can realize hydrogenation reduction of methyl acetate to prepare ethanol under low hydrogen pressure.

[0004] The invention provides a method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate, and the method comprises the following steps: using a copper-supported zinc oxide / carbon composite material as a catalyst and introducing hydrogen into a reactor to catalyze the hydrogenation reduction reaction of methyl acetate to prepare methanol and ethanol.

[0005] Preferably, the method for preparing the copper-supported zinc oxide / carbon composite material comprises the following steps: S1: dissolving trimesic acid in N,N-dimethylacetamide, and then adding zinc nitrate to react; S2: The product obtained after the reaction of S1 is added into a copper nitrate solution, and after stirring, standing, filtering and calcining, a copper-loaded zinc oxide / carbon composite material is obtained.

[0006] Preferably, the molar volume ratio of zinc nitrate, trimesic acid, copper nitrate and N,N-dimethylacetamide is 1 mmol:0.8-1.2 mmol:2.5-3.5 mmol:5-15 mL.

[0007] Preferably, the reaction temperature in S1 is 100-120° C. and the reaction time is 48-72 h.

[0008] Preferably, the calcination temperature in S2 is 400-600° C. and the calcination time is 3-5 h.

[0009] Preferably, the volume mass ratio of methyl acetate to catalyst is 10 mL:0.5-1.5 g; and the pressure after hydrogen is introduced into the reactor is 0.3-0.5 MPa.

[0010] Preferably, the temperature of the hydrogenation reduction reaction is 200-300° C., and the time is 6-24 h.

[0011] Beneficial technical effects of the present invention: The copper-supported zinc oxide / carbon composite material prepared in the present invention is used as a catalyst to realize the hydrogenation reduction of methyl acetate to produce ethanol under low hydrogen pressure, providing a new method and new idea for the development of green chemical technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 (a) SEM image of the copper-loaded MOF material proposed in the present invention, and (b) SEM image of the copper-loaded MOF material after high-temperature calcination; Figure 2 The chromatogram of the product prepared in Example 1 of the present invention; Figure 3 The chromatogram of the product prepared in Example 2 of the present invention; Figure 4 The chromatogram of the product prepared in Example 3 of the present invention; Figure 5 The chromatogram of the product prepared in Example 4 proposed by the present invention; Figure 6 The chromatogram is of the product prepared in Example 5 proposed by the present invention. DETAILED DESCRIPTION

[0013] The present invention will be further explained below in conjunction with specific embodiments.

[0014] Example 1 The method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate proposed in this embodiment comprises the following steps: heating methyl acetate to 100° C. without adding hydrogen and catalyst.

[0015] The test results are as follows Figure 2 As shown, it can be seen that methyl acetate will not react at low temperature, without catalyst and without hydrogenation.

[0016] Example 2 The method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate proposed in this embodiment comprises the following steps: using a copper-supported zinc oxide / carbon composite material as a catalyst and introducing hydrogen into a reactor to catalyze the hydrogenation reduction reaction of methyl acetate to prepare methanol and ethanol. Figure 1 shown.

[0017] The method steps for preparing the copper-supported zinc oxide / carbon composite material are as follows: S1: dissolving trimesic acid in N,N-dimethylacetamide, and then adding zinc nitrate to react; S2: The product obtained after the reaction of S1 is added into a copper nitrate solution, and after stirring, standing, filtering and calcining, a copper-loaded zinc oxide / carbon composite material is obtained.

[0018] The molar volume ratio of zinc nitrate, trimesic acid, copper nitrate and N,N-dimethylacetamide is 1 mmol:0.8 mmol:2.5 mmol:5 mL.

[0019] The reaction temperature in S1 is 90°C and the reaction time is 48h.

[0020] The calcination temperature in S2 is 400°C and the time is 4h.

[0021] The volume mass ratio of methyl acetate and catalyst is 100mL:1g; after hydrogen is introduced into the reactor, the pressure is 0.4MPa.

[0022] The temperature of the hydrogenation reduction reaction was 100°C and the time was 6 h.

[0023] The test results are as follows Figure 3 As shown in the figure, at 100°C, under the action of hydrogenation and catalyst, only a small amount of methanol is decomposed, and no ethanol is produced, indicating that at low temperature, methyl acetate will decompose a small amount when the catalyst is added, but no reduction reaction will occur. In addition, under this temperature and catalyst, the reaction structure without hydrogenation is basically the same as that with hydrogenation.

[0024] Example 3 The method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate proposed in this embodiment comprises the following steps: using a copper-supported zinc oxide / carbon composite material as a catalyst and introducing hydrogen into a reactor to catalyze the hydrogenation reduction reaction of methyl acetate to prepare methanol and ethanol.

[0025] The method for preparing the copper-supported zinc oxide / carbon composite material is the same as that in Example 1.

[0026] The volume mass ratio of methyl acetate and catalyst is 100mL:1g; after hydrogen is introduced into the reactor, the pressure is 0.4MPa.

[0027] The temperature of the hydrogenation reduction reaction is 220°C and the time is 6 hours.

[0028] The test results are as follows Figure 4 As shown, more methanol and a small amount of ethanol can be obtained under this condition, indicating that decomposition and reduction occur simultaneously, thereby obtaining more methanol.

[0029] Example 4 The method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate proposed in this embodiment comprises the following steps: using a copper-supported zinc oxide / carbon composite material as a catalyst and introducing hydrogen into a reactor to catalyze the hydrogenation reduction reaction of methyl acetate to prepare methanol and ethanol.

[0030] The method for preparing the copper-supported zinc oxide / carbon composite material is the same as that in Example 1.

[0031] The volume mass ratio of methyl acetate and catalyst is 100mL:1g; after hydrogen is introduced into the reactor, the pressure is 0.4MPa.

[0032] The temperature of the hydrogenation reduction reaction was 226°C and the time was 6 h.

[0033] The test results are as follows Figure 5 As shown, more methanol and a certain amount of ethanol can be obtained under this condition, indicating that decomposition and reduction occur simultaneously, thereby obtaining more methanol, and the ethanol yield increases, indicating that increasing the reaction temperature will promote the increase in the degree of reaction.

[0034] Example 5 The method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate proposed in this embodiment comprises the following steps: using a copper-supported zinc oxide / carbon composite material as a catalyst and introducing hydrogen into a reactor to catalyze the hydrogenation reduction reaction of methyl acetate to prepare methanol and ethanol.

[0035] The method for preparing the copper-supported zinc oxide / carbon composite material is the same as that in Example 1.

[0036] The volume mass ratio of methyl acetate and catalyst is 100mL:1g; after hydrogen is introduced into the reactor, the pressure is 0.4MPa.

[0037] The temperature of the hydrogenation reduction reaction is 220°C and the time is 24h.

[0038] The test results are as follows Figure 6 As shown, under this condition, the conversion rate of methyl acetate reached more than 90%, indicating that decomposition and reduction occurred simultaneously, thereby obtaining more methanol, and the ethanol yield was significantly increased, indicating that the reaction time had a significant effect on the conversion rate.

Claims

1. A method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate, characterized in that: The method comprises the following steps: using a copper-supported zinc oxide / carbon composite material as a catalyst and introducing hydrogen into a reaction kettle to catalyze the hydrogenation reduction reaction of methyl acetate to produce methanol and ethanol.

2. The method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate according to claim 1, characterized in that: The method steps for preparing the copper-supported zinc oxide / carbon composite material are as follows: S1: dissolving trimesic acid in N,N-dimethylacetamide, and then adding zinc nitrate to react; S2: The product obtained after the reaction of S1 is added into a copper nitrate solution, and after stirring, standing, filtering and calcining, a copper-loaded zinc oxide / carbon composite material is obtained.

3. The method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate according to claim 2, characterized in that: The molar volume ratio of zinc nitrate, trimesic acid, copper nitrate and N,N-dimethylacetamide is 1 mmol:0.8-1.2 mmol:2.5-3.5 mmol:5-15 mL.

4. The method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate according to claim 2, characterized in that: The reaction temperature in S1 is 100-120°C and the reaction time is 48-72h.

5. The method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate according to claim 2, characterized in that: The calcination temperature in S2 is 400-600°C and the time is 3-5h.

6. The method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate according to claim 1, characterized in that: The volume mass ratio of methyl acetate to catalyst is 10 mL:0.5-1.5 g; and the pressure after hydrogen is introduced into the reactor is 0.3-0.5 MPa.

7. The method for preparing ethanol and methanol by hydrogenation reduction of methyl acetate according to claim 1, characterized in that: The temperature of the hydrogenation reduction reaction is 200-300°C and the time is 6-24h.

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