Production method of glyoxylate

Abstract

The invention relates to a production method of glyoxylate. The method includes the steps of passing, by glycolate and an oxygen-containing gas through a reactor having at least one section of a catalyst bed layer under an oxidative dehydrogenation condition, wherein the catalyst bed layer has a mixture of an inert filler and a catalyst, in the mixture, the weight ratio of the inert filler to thecatalyst is (0.01-2): 1. The method can be used in industrial production of the glyoxylate.

Description

technical field

[0001] The present invention relates to a production method of glyoxylate. Background technique

[0002] Glyoxylate has the chemical properties of both aldehyde and ester, and can undergo various reactions, especially glyoxylic acid can be prepared by hydrolysis. Glyoxylic acid is an organic intermediate for synthesizing spices, medicines, food, varnish raw materials, dyes, and plastic additives. It can be used to produce oral penicillin, vanillin, mandelic acid and allantoin. Consumption has also been on an upward trend.

[0003] The preparation methods of glyoxylic acid at home and abroad mainly include: glyoxal oxidation method, oxalic acid electrolytic reduction method, dichloroacetic acid or dibromoacetic acid hydrolysis method, maleic anhydride ozone oxidation method, glycolic acid enzyme catalytic oxidation method, In addition, there are ethylene oxidation and acetaldehyde oxidation. Among them, glyoxal oxidation method is the main production method...

Examples

Embodiment 1

[0025] The methyl glycolate catalytic oxidation reactor is a tubular fixed-bed reactor, with a catalyst inside the tubular and a cooling medium outside the tubular. The oxygen-containing gas is air. The mol ratio of oxygen entering the reactor and methyl glycolate is 3:1, and the weight space velocity of methyl glycolate is 2.0h -1 , the reaction temperature was 350 °C, and the pressure was 1.0 MPa.

[0026] The catalyst uses alumina as a carrier, vanadium as an active component, and sodium as an auxiliary agent. The weight parts of vanadium are 10 parts, the weight parts of sodium are 2 parts, and the weight parts of the carrier are 88 parts.

[0027] The tube contains three stages of catalyst beds, the mixing ratio of inert alumina and catalyst in the first stage catalyst bed is 2:1, and the mixing ratio of inert alumina and catalyst in the second stage catalyst bed is 0.65:1 , the mixing ratio of inert alumina and catalyst in the third stage catalyst bed is 0.01:1.

[00...

Embodiment 2

[0030]The methyl glycolate catalytic oxidation reactor is a tubular fixed-bed reactor, with a catalyst inside the tubular and a cooling medium outside the tubular. The oxygen-containing gas is air. The mol ratio of oxygen entering the reactor and methyl glycolate is 2:1, and the weight space velocity of methyl glycolate is 1.0h -1 , the reaction temperature was 260 °C, and the pressure was 0.6 MPa.

[0031] The catalyst is the same as [Example 1].

[0032] The tube contains three stages of catalyst beds, the mixing ratio of inert alumina and catalyst in the first stage catalyst bed is 1.8:1, and the mixing ratio of inert alumina and catalyst in the second stage catalyst bed is 0.6:1 , the mixing ratio of inert alumina and catalyst in the catalyst bed of the third stage is 0.02:1.

[0033] Under the above conditions, the yield of methyl glyoxylate was 89.3%.

Embodiment 3

[0035] The methyl glycolate catalytic oxidation reactor is a tubular fixed-bed reactor, with a catalyst inside the tubular and a cooling medium outside the tubular. The oxygen-containing gas is a mixture of oxygen and nitrogen, and the oxygen content is 1 part and the nitrogen content is 99 parts by volume. The mol ratio of oxygen entering the reactor and methyl glycolate is 2:1, and the weight space velocity of methyl glycolate is 1.2h -1 , the reaction temperature was 300 °C, and the pressure was 0.8 MPa.

[0036] The catalyst uses silicon oxide as a carrier, vanadium as an active component, and molybdenum as an auxiliary agent.

[0037] There are two stages of catalyst beds in the tube, the mixing ratio of inert alumina and catalyst in the first stage catalyst bed is 1.5:1, and the mixing ratio of inert alumina and catalyst in the second stage catalyst bed is 0.35:1 .

[0038] Under the above conditions, the yield of methyl glyoxylate was 87.6%.

technical field

[0001] The present invention relates to a production method of glyoxylate. Background technique

[0002] Glyoxylate has the chemical properties of both aldehyde and ester, and can undergo various reactions, especially glyoxylic acid can be prepared by hydrolysis. Glyoxylic acid is an organic intermediate for synthesizing spices, medicines, food, varnish raw materials, dyes, and plastic additives. It can be used to produce oral penicillin, vanillin, mandelic acid and allantoin. Consumption has also been on an upward trend.

[0003] The preparation methods of glyoxylic acid at home and abroad mainly include: glyoxal oxidation method, oxalic acid electrolytic reduction method, dichloroacetic acid or dibromoacetic acid hydrolysis method, maleic anhydride ozone oxidation method, glycolic acid enzyme catalytic oxidation method, In addition, there are ethylene oxidation and acetaldehyde oxidation. Among them, glyoxal oxidation method is the main production method...

Examples

Embodiment 1

[0025] The methyl glycolate catalytic oxidation reactor is a tubular fixed-bed reactor, with a catalyst inside the tubular and a cooling medium outside the tubular. The oxygen-containing gas is air. The mol ratio of oxygen entering the reactor and methyl glycolate is 3:1, and the weight space velocity of methyl glycolate is 2.0h -1 , the reaction temperature was 350 °C, and the pressure was 1.0 MPa.

[0026] The catalyst uses alumina as a carrier, vanadium as an active component, and sodium as an auxiliary agent. The weight parts of vanadium are 10 parts, the weight parts of sodium are 2 parts, and the weight parts of the carrier are 88 parts.

[0027] The tube contains three stages of catalyst beds, the mixing ratio of inert alumina and catalyst in the first stage catalyst bed is 2:1, and the mixing ratio of inert alumina and catalyst in the second stage catalyst bed is 0.65:1 , the mixing ratio of inert alumina and catalyst in the third stage catalyst bed is 0.01:1.

[00...

Embodiment 2

[0030]The methyl glycolate catalytic oxidation reactor is a tubular fixed-bed reactor, with a catalyst inside the tubular and a cooling medium outside the tubular. The oxygen-containing gas is air. The mol ratio of oxygen entering the reactor and methyl glycolate is 2:1, and the weight space velocity of methyl glycolate is 1.0h -1 , the reaction temperature was 260 °C, and the pressure was 0.6 MPa.

[0031] The catalyst is the same as [Example 1].

[0032] The tube contains three stages of catalyst beds, the mixing ratio of inert alumina and catalyst in the first stage catalyst bed is 1.8:1, and the mixing ratio of inert alumina and catalyst in the second stage catalyst bed is 0.6:1 , the mixing ratio of inert alumina and catalyst in the catalyst bed of the third stage is 0.02:1.

[0033] Under the above conditions, the yield of methyl glyoxylate was 89.3%.

Embodiment 3

[0035] The methyl glycolate catalytic oxidation reactor is a tubular fixed-bed reactor, with a catalyst inside the tubular and a cooling medium outside the tubular. The oxygen-containing gas is a mixture of oxygen and nitrogen, and the oxygen content is 1 part and the nitrogen content is 99 parts by volume. The mol ratio of oxygen entering the reactor and methyl glycolate is 2:1, and the weight space velocity of methyl glycolate is 1.2h -1 , the reaction temperature was 300 °C, and the pressure was 0.8 MPa.

[0036] The catalyst uses silicon oxide as a carrier, vanadium as an active component, and molybdenum as an auxiliary agent.

[0037] There are two stages of catalyst beds in the tube, the mixing ratio of inert alumina and catalyst in the first stage catalyst bed is 1.5:1, and the mixing ratio of inert alumina and catalyst in the second stage catalyst bed is 0.35:1 .

[0038] Under the above conditions, the yield of methyl glyoxylate was 87.6%.