Glyoxylic ester product, process for its synthesis and use thereof

Abstract

The application discloses a glyoxylic ester product and a preparation method and application thereof. In addition to the glyoxylic ester, the glyoxylic ester product also contains appropriate glycollic ester, oxalic monoester, acetal + hemiacetal, glyoxylic ester, polymer and water. In the process of synthesizing alpha-hydroxy-4-phenyl-4-pentenoic acid ethyl ester, the components other than the glyoxylic ester can form a combination with the ferric trichloride catalyst, and the combination is more conducive to the catalyst to play its role, promotes the reaction and improves the product yield.

Description

Technical Field

[0001] This invention relates to a glyoxylate product and its synthesis method. Background Technology

[0002] The α-ketone functional group in glyoxylates possesses high reactivity and can be used to synthesize a variety of drugs and natural compounds. For example, glyoxylates can be used to synthesize compounds with high optical efficiency through asymmetric aldol condensation with aldehydes; 3-amino-α-hydroxy-β-ester-3-quaternary carbonyl indole compounds with antitumor properties can be synthesized via the Aldol reaction; and α-hydroxy-4-phenyl-4-pentenoate can be synthesized by reacting with α-methylstyrene using a Lewis acid catalyst.

[0003] Currently, the synthesis methods of glyoxylates are mainly divided into tartrate oxidation, maleic acid ozone oxidation, and diethyl butadiene ester oxidation, depending on the source of raw materials. However, these methods generally suffer from low yields, large amounts of waste liquid, or the presence of harmful chemicals that affect downstream use, and none have seen industrial applications. Therefore, there are very few glyoxylate products available on the market, and even those that are found to contain high levels of acetals and other components. To solve the problem of acetals, CN87100429 proposes adding higher carbon alcohols with boiling points above 180°C to materials containing glyoxylates and acetals, and first distilling off water and / or alcohol ROH at a maximum pressure of 800 mbar, and finally distilling off glyoxylates. This not only increases energy consumption but also consumes a large amount of high-boiling-point alcohols.

[0004] In recent years, China's coal-to-ethylene glycol technology has developed rapidly, with an annual production capacity of 10 million tons of ethylene glycol from syngas reaching 2021. This process produces glycolate as a byproduct during the hydrogenation of oxalate. Against this backdrop, utilizing glycolate to synthesize glyoxylate, and rationally controlling the composition of the glyoxylate product, yields glyoxylate intermediates that can be directly used in organic synthesis, which has significant social and economic benefits. Summary of the Invention

[0005] The technical problem to be solved by this invention is to improve the quality of glyoxylate products in a simple way, and to provide a new glyoxylate product for organic synthesis. This product has a reasonable distribution of acetal, oxalate, and glycolate content, which can meet the needs of downstream applications, while simplifying the synthesis method and improving the yield.

[0006] The first aspect of this invention is to provide a glyoxylate product, comprising the following components by weight:

[0007]

[0008]

[0009] Furthermore, the glyoxylate is preferably methyl glyoxylate or ethyl glyoxylate.

[0010] Furthermore, the oxalate monoester is monomethyl oxalate or monoethyl oxalate.

[0011] Further, the acetal + hemiacetal is a condensation product of glyoxylate and one or two molecules of methanol, ethanol, methyl glycolate, or ethyl glycolate, with the following structural formula:

[0012]

[0013] R1 is an ester group, and R2 and R3 are methyl, ethyl or ester groups.

[0014] Furthermore, the polymer is a polymer of glyoxylic acid or glycolic acid.

[0015] Furthermore, the platinum-cobalt color of the glyoxylate product is not higher than 70.

[0016] A second aspect of the present invention provides a method for synthesizing a glyoxylate product, comprising the following steps:

[0017] a) An oxidation reaction is carried out by contacting glycolate and oxygen-containing gas with a catalyst at a temperature of 170–230°C, preferably 180–220°C; a pressure of -0.5–1 MPa, preferably -0.5–0.5 MPa; and a liquid hourly space velocity (WHSV) of 1.6–5 h⁻¹. -1 The preferred glycolate solution has a weight hourly space velocity (WHSV) of 1.6–2 h⁻¹. -1 ;

[0018] b) The reaction product of step a) is separated into gas and liquid phases to obtain glyoxylate product.

[0019] Furthermore, the alcohol impurity content in the glycolate ester described in step a) is less than 1%, preferably less than 0.3%.

[0020] Further, the oxygen-containing gas mentioned in step a) is a mixture of nitrogen and oxygen or nitrogen and air, wherein the nitrogen volume hourly space velocity in the oxygen-containing gas is 1000–4000 h⁻¹. -1 .

[0021] Furthermore, in the synthesis method, the molar content of oxygen in the exhaust gas is controlled to be 0.1% to 1%, preferably 0.2% to 0.7%. The oxygen content is controlled by adjusting the oxygen or air flow rate. A flow controller is installed on the oxygen or air pipeline; a detection device is installed on the exhaust gas pipeline to continuously detect the oxygen content in the gas phase.

[0022] Furthermore, the gas phase obtained from gas-liquid separation in step b) is a tail gas stream containing unreacted oxygen-containing gas and carbon dioxide gas.

[0023] Since the oxidation of glycolate to glyoxylate is a cascade reaction, further oxidation can produce oxalate or carbon dioxide. Therefore, improving the uniformity of catalyst activity distribution is beneficial for simultaneously achieving higher feed conversion rates and reducing the content of oxalate byproducts in the final product. Furthermore, studies have found that an unreasonable distribution of catalyst acid strength can increase the nucleophilic addition reaction between the carbonyl oxygen atom in glyoxylate and the hydroxyl group in the reactants, generating large amounts of hemiacetals and acetals.

[0024] Furthermore, the aforementioned catalyst for synthesizing glyoxylate comprises, by weight parts:

[0025] a) 0.5 to 15 parts of the active component copper, calculated as elemental copper;

[0026] b) 0.1 to 10 parts of the first auxiliary agent, calculated as an element;

[0027] c) 0.01 to 1 part of the second auxiliary agent, calculated as an element;

[0028] d) 84–99.39 vectors;

[0029] The catalyst, as characterized by NH3-TPD, exhibits a desorption peak in the range of 50℃ to 300℃.

[0030] Furthermore, the catalyst, as characterized by NH3-TPD, exhibits an NH3-TPD acidity in the range of 50℃ to 180℃ that accounts for more than 80% of the total NH3-TPD acidity below 300℃. Preferably, the NH3-TPD acidity in the range of 50℃ to 180℃ accounts for more than 90% of the total NH3-TPD acidity below 300℃. More preferably, the NH3-TPD acidity in the range of 50℃ to 180℃ accounts for more than 92% of the total acidity below 300℃.

[0031] Further, the molar ratio of the second auxiliary agent to the first auxiliary agent is 0.01 to 0.02. Further, the first auxiliary agent is selected from at least one of molybdenum, iron, vanadium, cobalt, and manganese; the second auxiliary agent is selected from at least one of lanthanum, potassium, calcium, sodium, and barium.

[0032] Furthermore, the carrier is selected from at least one of titanium oxide, silicon oxide, magnesium oxide, zirconium oxide, and cerium oxide, preferably at least one of silicon oxide and magnesium oxide.

[0033] Furthermore, the particles with a particle size distribution of 30-60 nm account for more than 85% of the total number of carrier particles, and preferably, the particles with a particle size distribution of 30-60 nm account for 90% to 95% of the total number of carrier particles.

[0034] Furthermore, the catalyst was characterized by XRD testing and showed no obvious copper characteristic peaks at 2θ = 50.4° and 2θ = 74.1°, and no obvious copper oxide characteristic peaks at 2θ = 29.7°, 36.6°, 42.4°, 61.5°, 73.7°, and 77.6°.

[0035] Furthermore, the catalyst exhibits only one hydrogen reduction peak for the active component Cu as characterized by H2-TPR testing. The H2-TPR characterization data for the catalyst shows a Cu reduction peak temperature of 200℃±10℃, preferably 200℃±7℃.

[0036] Furthermore, the temperature difference between the end position of hydrogen reduction and the beginning position of peak elution of the active component Cu, as characterized by H2-TPR testing, is <60℃, preferably <40℃, and more preferably <30℃.

[0037] Furthermore, the molar ratio of the first auxiliary agent to the active component copper is 0.2 to 5, preferably 0.3 to 4.

[0038] Furthermore, the preparation method of the aforementioned catalyst for synthesizing glyoxylate includes the following steps:

[0039] a) Prepare a soluble salt solution of the active ingredient and the first adjuvant, and adjust the pH value to 2-5;

[0040] b) Mix the carrier powder with a low-carbon alcohol solution with a boiling point below 110°C to obtain a slurry;

[0041] c) Add the solution obtained in step a) to the slurry obtained in step b) while stirring;

[0042] d) Recirculate the slurry obtained in step c) at 50–100°C for 2–20 hours, and add the second additive during or after heating;

[0043] e) The slurry obtained in step d) is dried and heat-treated to obtain a catalyst for the oxidative synthesis of glyoxylate.

[0044] Furthermore, in step a), the pH of the solution is adjusted using acid and / or ammonia.

[0045] Further, in step a), the first auxiliary agent is selected from at least one of molybdenum, iron, vanadium, cobalt, and manganese;

[0046] Further, in step a), the mass concentration of the soluble salt aqueous solution of the active component and the first auxiliary agent is 0.25% to 20%. The molar ratio of copper between the first auxiliary agent and the active component is 0.2 to 5, preferably 0.3 to 4.

[0047] Further, in step b), the lower alcohol is selected from at least one of C1 to C4 alcohols. The mass concentration of the lower alcohol solution is 2% to 20%. The mass ratio of the lower alcohol to the carrier is 0.02 to 0.2:1.

[0048] Furthermore, in step b), the particle size distribution of the carrier powder is as follows: particles of 30-60 nm account for more than 85% of the total number of particles, preferably 90% to 95%.

[0049] Furthermore, in step b), the carrier powder is preferably a carrier powder treated with an organic amine solution.

[0050] Furthermore, the organic amine solution treatment steps include:

[0051] 1) Prepare an organic amine solution and adjust the pH to 9-12;

[0052] 2) Mix the carrier powder with the solution obtained in step 1), stir at 120-180°C for 2-24 hours, filter and wash until the conductivity of the washing solution is less than 100 μs / cm, preferably less than 50 μs / cm, and dry the filtered material to obtain the carrier powder.

[0053] The organic amine mentioned in step 1) includes, but is not limited to, one or more of fatty amines, amides, and alkanolamines, preferably one or more of fatty amines and amides. The mass concentration of the organic amine solution is 0.1% to 1.3%.

[0054] The pH adjustment described in step 1) is preferably performed using sodium hydroxide and / or nitric acid.

[0055] Furthermore, in step c), the feeding time is controlled to be 30–180 min during the feeding process.

[0056] Further, in step d), the second auxiliary agent is selected from at least one of lanthanum, potassium, calcium, sodium, and barium. The second auxiliary agent is added to the system in the form of a solid compound, such as a hydroxide or carbonate.

[0057] Furthermore, the drying described in step e) can be performed using any conventional drying method to evaporate excess water and alcohol from the refluxed slurry.

[0058] Further, the heat treatment described in step e) is preferably performed using water vapor containing 0.1% to 0.5% carbonate by mass at a volume hourly space velocity of 300 to 2000 h⁻¹. -1 Treat at 460–560℃ for 4–10 hours.

[0059] Further, the carbonate in step e) can be at least one of dimethyl carbonate and diethyl carbonate.

[0060] A third aspect of the present invention is to provide the use of a glyoxylate product in the synthesis of ethyl α-hydroxy-4-phenyl-4-pentenoate.

[0061] Furthermore, the glyoxylate product is used as a ferric chloride catalyst in the synthesis of ethyl α-hydroxy-4-phenyl-4-pentenoate.

[0062] In the synthesis of ethyl α-hydroxy-4-phenyl-4-pentenoate from glyoxylate, appropriate amounts of components other than glyoxylate, such as glycolate and monooxalate, can form complexes with the ferric chloride catalyst. These complexes are more conducive to the catalyst's function, promoting the reaction and increasing the product yield. However, if the content of components other than glyoxylate is too high, the effective active site concentration will decrease due to the formation of a large number of ligands. This invention directly synthesizes a glyoxylate product with suitable glycolate and monooxalate contents. It can be directly used to synthesize ethyl α-hydroxy-4-phenyl-4-pentenoate and has a promoting effect on the catalyst used in the synthesis process.

[0063] Furthermore, the catalyst for synthesizing glyoxylate products in this invention exhibits a uniform distribution of active sites, a low redox activation point, and a reasonable acid distribution. During catalyst preparation, a first promoter is used as a multivalent promoter to regulate the catalyst's electronic effect, and a second promoter combined with hydrothermal treatment is used to control the catalyst's acid distribution. Moreover, the catalyst is further enhanced by employing a support with uniform particle size distribution and pretreating the support under a specific atmosphere to adjust its bonding force with the active components. Attached Figure Description

[0064] Figure 1 The NH3-TPD spectrum of catalyst A1 prepared in Example 1 is shown. The desorption peaks appear at 151℃ and 237℃, and the acidity of NH3-TPD in the range of 50℃ to 180℃ accounts for 97.6% of the total acidity of NH3-TPD below 300℃.

[0065] Figure 2 The XRD pattern of catalyst A1 prepared in Example 1 shows no obvious characteristic peaks of Cu or CuO.

[0066] Figure 3 The image shows the H2-TPR reduction spectrum of catalyst A1 prepared in Example 1; Cu has only one hydrogen reduction peak.

[0067] Figure 4 The NH3-TPD spectrum of catalyst B1 prepared in Comparative Example 1 is shown. The desorption peaks appear at 158℃ and 243℃, and the acidity of NH3-TPD in the range of 50℃ to 180℃ accounts for 93.5% of the total acidity of NH3-TPD below 300℃. Detailed Implementation

[0068] The present invention will be further described below with reference to specific embodiments, but it should be understood that the specific embodiments do not constitute a limitation on the scope of protection.

[0069] In this invention, the catalyst components were tested using a Rigaku ZSX 100e XRF instrument under the following conditions: rhodium target as excitation source, maximum power 3600W, tube voltage 60kV, and tube current 120mA.

[0070] In this invention, the particle size distribution of the catalyst support was determined using a Zetasizer Nano ZS 90 (Malvin) laser particle size analyzer. Before testing, the sample was dispersed in an ultrasonic generator for 20 minutes using water as the dispersion medium, and then tested to output the particle size analysis results.

[0071] In this invention, the catalyst H2-TPR characterization was performed using a Micromeritics AutoChem II 2920 chemisorption analyzer. A 50 mg sample was taken, and before testing, it was purged with Ar at room temperature, followed by a programmed reduction from room temperature to 300 °C using a 10% (v / v) H2 / Ar mixed gas at a rate of 10 °C / min. The reduction peak start temperature was defined as the temperature at which the tangent line drawn at the inflection point before the copper reduction peak in the TPR spectrum intersects with the peak bottom, and the reduction peak end temperature was defined as the temperature at which the tangent line drawn at the inflection point after the copper reduction peak in the TPR spectrum intersects with the peak bottom.

[0072] In this invention, the XRD diffraction peaks of copper and copper oxide in the catalyst were characterized using a Bruker D8 polycrystalline X-ray diffractometer (XRD) with a graphite monochromator, a Cu-Kα ray source (Kα1 wavelength λ = 0.15406 nm), a scanning angle 2θ of 5–80°, and a scanning rate of 1° / min.

[0073] In this invention, the temperature-programmed desorption (NH3-TPD) characterization of the catalyst was performed using a temperature-programmed adsorption apparatus. 0.1 g of molecular sieve sample was weighed and placed in a quartz adsorption tube. A carrier gas was introduced, and the temperature was raised to 550 °C at a rate of 20 °C / min, held for 2 h, to remove impurities adsorbed on the molecular sieve sample. After cooling, the carrier gas was switched to an NH3-He mixture, held for 30 min, to allow the catalyst sample to reach NH3 saturation. The NH3-He mixture was then switched to high-purity He carrier gas, and the sample was purged for 1 h to adsorb NH3. Finally, the temperature was raised to 600 °C at a rate of 10 °C / min to obtain the temperature-programmed desorption curve. The desorbed ammonia was detected using a thermal conductivity cell. After converting the temperature-programmed desorption curve into an NH3 desorption rate-temperature curve, the acid content could be obtained by analyzing the peak shapes.

[0074] In this invention, the composition of the liquid phase product was determined using a Shimadzu LC-20A liquid chromatograph. Analytical conditions: Agilent C18 column; column oven temperature 35°C; detection wavelength 212 nm; injection volume 2 μL.

[0075] In this invention, the platinum-cobalt color of the liquid-phase product is determined using a standard colorimetric method.

[0076] The present invention will be further illustrated by the following examples.

[0077]

Example 1

[0078] Dissolve 0.5g of ethylenediamine in 100ml of water and adjust the pH to 10 to obtain solution a. Add 20g of silica powder (90% of which have a particle size of 30-60nm) to solution a, place in a pressure vessel, maintain a constant temperature of 130℃, and stir for 5 hours. After the process, filter the carrier, wash it multiple times with deionized water, and measure the conductivity of the washing solution. When the conductivity of the washing solution is less than 50μs / cm, the washing is considered complete. Filter out the powder, dry it at 120℃ to obtain powder b.

[0079] Dissolve 5.2g of copper nitrate and 8.3g of ferric nitrate in 120ml of deionized water and adjust the pH to 3 to obtain solution c.

[0080] Powder b was added to 50 ml of 5% propanol aqueous solution to obtain slurry d.

[0081] Under stirring, solution c is added to slurry d, and the feeding time is controlled at 120 min to obtain slurry e.

[0082] After reflux heating of slurry e at 100℃ for 8 hours, 0.12g of potassium hydroxide was added, and reflux heating was continued for 4 hours to obtain slurry f.

[0083] Excess water and alcohol in slurry f are evaporated to obtain powder g.

[0084] The powder (g) was loaded into a tube furnace and introduced at 500°C with a volumetric space velocity (VHSV) of 1000 h⁻¹. -1 Catalyst A1 was obtained by steam heat treatment with 0.2% dimethyl carbonate for 5 hours.

[0085] The NH3-TPD spectrum of catalyst A1 is as follows: Figure 1 As shown, desorption peaks appear at 151℃ and 237℃, and the acidity of NH3-TPD in the range of 50℃ to 180℃ accounts for 97.6% of the total acidity of NH3-TPD below 300℃. The XRD pattern of catalyst A1 is shown below. Figure 2 As shown, there are no obvious characteristic peaks of Cu or CuO; the H2-TPR reduction spectrum of the catalyst is as follows. Figure 3 As shown, Cu has only one hydrogen reduction peak, and the analysis and test results are shown in Table 1.

[0086]

Example 2

[0087] Dissolve 0.5g of ethylenediamine in 100ml of water and adjust the pH to 10 to obtain solution a. Add 20g of silica powder (90% of which have a particle size of 30-60nm) to solution a, place in a pressure vessel, maintain a constant temperature of 130℃, and stir for 5 hours. After the process, filter the carrier, wash it multiple times with deionized water, and measure the conductivity of the washing solution. When the conductivity of the washing solution is less than 50μs / cm, the washing is considered complete. Filter out the powder, dry it at 120℃ to obtain powder b.

[0088] Dissolve 5.2g of copper nitrate and 8.3g of ferric nitrate in 120ml of deionized water and adjust the pH to 3 to obtain solution c.

[0089] Powder b was added to 50 ml of 5% propanol aqueous solution to obtain slurry d.

[0090] Under stirring, solution c is added to slurry d, and the feeding time is controlled at 120 min to obtain slurry e.

[0091] After reflux heating of slurry e at 100℃ for 8 hours, 0.08g of potassium hydroxide was added, and reflux heating was continued for 4 hours to obtain slurry f.

[0092] Excess water and alcohol in slurry f are evaporated to obtain powder g.

[0093] The powder (g) was loaded into a tube furnace and introduced at 500°C with a volumetric space velocity (VHSV) of 1000 h⁻¹. -1 Catalyst A2 was obtained by heat treatment with steam containing 0.2% dimethyl carbonate for 5 hours. The analytical results are shown in Table 1.

[0094]

Example 3

[0095] Dissolve 0.5g of ethylenediamine in 100ml of water and adjust the pH to 10 to obtain solution a. Add 20g of silica powder (90% of which have a particle size of 30-60nm) to solution a, place in a pressure vessel, maintain a constant temperature of 130℃, and stir for 5 hours. After the process, filter the carrier, wash it multiple times with deionized water, and measure the conductivity of the washing solution. When the conductivity of the washing solution is less than 50μs / cm, the washing is considered complete. Filter out the powder, dry it at 120℃ to obtain powder b.

[0096] Dissolve 5.2g of copper nitrate and 8.3g of ferric nitrate in 120ml of deionized water and adjust the pH to 3 to obtain solution c.

[0097] Powder b was added to 50 ml of 5% propanol aqueous solution to obtain slurry d.

[0098] Under stirring, solution c is added to slurry d, and the feeding time is controlled at 120 min to obtain slurry e.

[0099] After reflux heating of slurry e at 100℃ for 8 hours, 0.16g of potassium hydroxide was added, and reflux heating was continued for 4 hours to obtain slurry f.

[0100] Excess water and alcohol in slurry f are evaporated to obtain powder g.

[0101] The powder (g) was loaded into a tube furnace and introduced at 500°C with a volumetric space velocity (VHSV) of 1000 h⁻¹. -1 Catalyst A3 was obtained by heat treatment with steam containing 0.2% dimethyl carbonate for 5 hours. The analytical results are shown in Table 1.

[0102]

Example 4

[0103] Dissolve 0.7g of trimethylamine in 100ml of water and adjust the pH to 10 to obtain solution a. Add 20g of silica powder (90% of which have a particle size of 30-60nm) to solution a, place in a pressure vessel, maintain a constant temperature of 140℃, and stir for 5 hours. After the process, filter the carrier, wash it multiple times with deionized water, and measure the conductivity of the washing solution. When the conductivity of the washing solution is less than 50μs / cm, the washing is considered complete. Filter out the powder, dry it at 120℃ to obtain powder b.

[0104] Dissolve 5.2g of copper nitrate and 8.3g of ferric nitrate in 120ml of deionized water and adjust the pH to 3 to obtain solution c.

[0105] Powder b was added to 50 ml of 5% ethanol aqueous solution to obtain slurry d.

[0106] Under stirring, solution c is added to slurry d, and the feeding time is controlled at 120 min to obtain slurry e.

[0107] After reflux heating of slurry e at 100℃ for 8 hours, 0.37g of barium hydroxide was added, and reflux heating was continued for 4 hours to obtain slurry f.

[0108] Excess water and alcohol in slurry f are evaporated to obtain powder g.

[0109] The powder (g) was loaded into a tube furnace and introduced at 460°C with a volumetric space velocity (VHSV) of 1000 h⁻¹. -1 The catalyst A4 was subjected to steam heat treatment containing 0.2% dimethyl carbonate for 5 hours. The analytical results are shown in Table 1.

[0110]

Example 5

[0111] Dissolve 0.5g of ethylenediamine in 100ml of water and adjust the pH to 10 to obtain solution a. Add 20g of silica powder (90% of which have a particle size of 30-60nm) to solution a, place in a pressure vessel, maintain a constant temperature of 140℃, and stir for 5 hours. After the process, filter the carrier, wash it multiple times with deionized water, and measure the conductivity of the washing solution. When the conductivity of the washing solution is less than 50μs / cm, the washing is considered complete. Filter out the powder, dry it at 120℃ to obtain powder b.

[0112] Dissolve 0.3g of copper nitrate and 0.1g of ferric nitrate in 120ml of deionized water and adjust the pH to 3 to obtain solution c.

[0113] Powder b was added to 50 ml of 5% propanol aqueous solution to obtain slurry d.

[0114] Solution c is added to slurry d while stirring, and the addition time is controlled at 120 min. Slurry e is obtained.

[0115] After reflux heating of slurry e at 100℃ for 8 hours, 0.12g of potassium hydroxide was added, and reflux heating was continued for 4 hours to obtain slurry f.

[0116] Excess water and alcohol in slurry f are evaporated to obtain powder g.

[0117] The powder (g) was loaded into a tube furnace and introduced at 500°C with a volumetric space velocity (VHSV) of 1000 h⁻¹. -1 Catalyst A5 was obtained by heat treatment with steam containing 0.2% dimethyl carbonate for 5 hours. The analytical results are shown in Table 1.

[0118]

Example 6

[0119] Dissolve 0.5g of ethylenediamine in 100ml of water and adjust the pH to 10 to obtain solution a. Add 20g of silica powder (90% of which have a particle size of 30-60nm) to solution a, place in a pressure vessel, maintain a constant temperature of 140℃, and stir for 5 hours. After the process, filter the carrier, wash it multiple times with deionized water, and measure the conductivity of the washing solution. When the conductivity of the washing solution is less than 50μs / cm, the washing is considered complete. Filter out the powder, dry it at 120℃ to obtain powder b.

[0120] Dissolve 11.5g of copper nitrate and 11g of ferric nitrate in 120ml of deionized water and adjust the pH to 3 to obtain solution c.

[0121] Powder b was added to 50 ml of 5% propanol aqueous solution to obtain slurry d.

[0122] Solution c is added to slurry d while stirring, and the addition time is controlled at 120 min. Slurry e is obtained.

[0123] After reflux heating of slurry e at 100℃ for 8 hours, 0.12g of potassium hydroxide was added, and reflux heating was continued for 4 hours to obtain slurry f.

[0124] Excess water and alcohol in slurry f are evaporated to obtain powder g.

[0125] The powder (g) was loaded into a tube furnace and introduced at 500°C with a volumetric space velocity (VHSV) of 1000 h⁻¹. -1 Catalyst A6 was obtained by heat treatment with steam containing 0.2% dimethyl carbonate for 5 hours. The analytical results are shown in Table 1.

[0126]

Example 7

[0127] Dissolve 0.5g of ethylenediamine in 100ml of water and adjust the pH to 10 to obtain solution a. Add 20g of silica powder (90% of which have a particle size of 30-60nm) to solution a, place in a pressure vessel, maintain a constant temperature of 140℃, and stir for 5 hours. After the process, filter the carrier, wash it multiple times with deionized water, and measure the conductivity of the washing solution. When the conductivity of the washing solution is less than 50μs / cm, the washing is considered complete. Filter out the powder, dry it at 120℃ to obtain powder b.

[0128] Dissolve 5g of copper nitrate, 1.8g of cobalt acetate, and 2.5g of manganese acetate in 120ml of deionized water, and adjust the pH to 3 to obtain solution c.

[0129] Powder b was added to 50 ml of 5% propanol aqueous solution to obtain slurry d.

[0130] Solution c is added to slurry d while stirring, and the addition time is controlled at 120 min. Slurry e is obtained.

[0131] After reflux heating of slurry e at 100℃ for 8 hours, 0.12g of potassium hydroxide was added, and reflux heating was continued for 4 hours to obtain slurry f.

[0132] Excess water and alcohol in slurry f are evaporated to obtain powder g.

[0133] The powder (g) was loaded into a tube furnace and introduced at 500°C with a volumetric space velocity (VHSV) of 2000 h⁻¹. -1 Catalyst A7 was obtained by heat treatment with steam containing 0.2% dimethyl carbonate for 5 hours. The analytical results are shown in Table 1.

[0134]

Example 8

[0135] Dissolve 0.5g of ethylenediamine in 100ml of water and adjust the pH to 10 to obtain solution a. Add 10g of titanium dioxide powder (85% of the total particles with a particle size of 30-60nm) and 10g of zirconium oxide powder (87% of the total crystals with a particle size of 30-60nm) to solution a, place in a pressure vessel, maintain a constant temperature of 140℃, and stir for 5 hours. After the process, filter the carrier, wash it multiple times with deionized water, and measure the conductivity of the washing solution. When the conductivity of the washing solution is less than 50μs / cm, the washing is considered complete. Filter out the powder, dry it at 120℃ to obtain powder b.

[0136] Dissolve 5g of copper nitrate and 8.5g of ferric nitrate in 120ml of deionized water and adjust the pH to 4 to obtain solution c.

[0137] Powder b was added to 50 ml of 5% propanol aqueous solution to obtain slurry d.

[0138] Solution c is added to slurry d while stirring, and the addition time is controlled at 120 min. Slurry e is obtained.

[0139] After reflux heating of slurry e at 100℃ for 8 hours, 0.12g of potassium hydroxide was added, and reflux heating was continued for 4 hours to obtain slurry f.

[0140] Excess water and alcohol in slurry f are evaporated to obtain powder g.

[0141] The powder (g) was loaded into a tube furnace and introduced at 500°C with a volumetric space velocity (VHSV) of 1000 h⁻¹. -1 Catalyst A8 was obtained by heat treatment with steam containing 0.2% dimethyl carbonate for 5 hours. The analytical results are shown in Table 1.

[0142]

Example 9

[0143] Dissolve 0.5g of ethylenediamine in 100ml of water and adjust the pH to 10 to obtain solution a. Add 20g of silica powder (90% of which have a particle size of 30-60nm) to solution a, place in a pressure vessel, maintain a constant temperature of 130℃, and stir for 5 hours. After the process, filter the carrier, wash it multiple times with deionized water, and measure the conductivity of the washing solution. When the conductivity of the washing solution is less than 50μs / cm, the washing is considered complete. Filter out the powder, dry it at 120℃ to obtain powder b.

[0144] Dissolve 5.2g of copper nitrate and 8.3g of ferric nitrate in 120ml of deionized water and adjust the pH to 3 to obtain solution c.

[0145] Powder b was added to 50 ml of 5% propanol aqueous solution to obtain slurry d.

[0146] Under stirring, solution c is added to slurry d, and the feeding time is controlled at 120 min to obtain slurry e.

[0147] After reflux heating of slurry e at 100℃ for 8 hours, 0.7g of potassium hydroxide was added, and reflux heating was continued for 4 hours to obtain slurry f.

[0148] Excess water and alcohol in slurry f are evaporated to obtain powder g.

[0149] The powder (g) was loaded into a tube furnace and introduced at 500°C with a volumetric space velocity (VHSV) of 1000 h⁻¹. -1 Catalyst A9 was obtained by heat treatment with steam containing 0.2% dimethyl carbonate for 5 hours.

[0150]

Comparative Example 1

[0151] According to the formulation of Example 1, 5.2g of copper nitrate, 8.3g of ferric nitrate, and 0.12g of potassium hydroxide were dissolved in deionized water and then impregnated with 20g of silica powder carrier. The powder was dried at 110°C to obtain g of powder. The g of powder was placed in a tube furnace and purged at 500°C with a volumetric hourly space velocity of 1000 h⁻¹. -1 Catalyst B1 was obtained by heat treatment with steam containing 0.2% dimethyl carbonate for 5 hours. The analytical results are shown in Table 1.

[0152] [Comparative Example 2]

[0153] Following the formulation and method of Example 1, except that potassium hydroxide was not added during the preparation process, 0.5g of ethylenediamine was dissolved in 100ml of water, and the pH was adjusted to 10 to obtain solution a. 20g of silica powder with a particle size of 30-60nm (90% of the total particles) was added to solution a, placed in a pressure vessel, and kept at a constant temperature of 130℃ for 5 hours with stirring. After completion, the carrier was filtered, washed multiple times with deionized water, and the conductivity of the washing solution was measured. When the conductivity of the washing solution was less than 50μs / cm, the washing was considered complete, the powder was filtered out, and dried at 120℃ to obtain powder b.

[0154] Dissolve 5.2g of copper nitrate and 8.3g of ferric nitrate in 120ml of deionized water and adjust the pH to 3 to obtain solution c.

[0155] Powder b was added to 50 ml of 5% propanol aqueous solution to obtain slurry d.

[0156] Under stirring, solution c is added to slurry d, and the feeding time is controlled at 120 min to obtain slurry e.

[0157] Slurry e was refluxed and heated at 100°C for 8 hours to obtain slurry f.

[0158] Excess water and alcohol in slurry f are evaporated to obtain powder g.

[0159] The powder (g) was loaded into a tube furnace and introduced at 500°C with a volumetric space velocity (VHSV) of 1000 h⁻¹. -1 Catalyst B2 was obtained by heat treatment with steam containing 0.2% dimethyl carbonate for 5 hours. The analytical results are shown in Table 1.

[0160]

Example 10

[0161] The catalysts obtained in Examples 1-9 were used to synthesize glyoxylate products. Methyl glycolate was used as a raw material, mixed with oxygen and nitrogen. The reaction was carried out at a temperature of 205°C, a pressure of 0.2 MPa, and a methyl glycolate weight hourly space velocity of 2 h⁻¹. -1 Nitrogen volume hourly space velocity 3000 h⁻¹ -1 Glyoxylate products were synthesized under the condition of 0.3% oxygen molar content in the exhaust gas. The analysis results of the synthesized glyoxylate products are shown in Table 2.

[0162]

Example 11

[0163] The glyoxylate product obtained in Example 10 was used for the synthesis of ethyl α-hydroxy-4-phenyl-4-pentenoate. The reaction conditions were as follows: ferric chloride, an inexpensive and environmentally friendly catalyst, was used; the molar ratio of α-methylstyrene to ethyl glyoxylate was 1:1; the reaction temperature was 30°C; and the reaction time was 5 h. The yield results of ethyl α-hydroxy-4-phenyl-4-pentenoate are shown in Table 2.

[0164] [Comparative Example 3]

[0165] The catalysts obtained in Comparative Examples 1-2 were used to synthesize glyoxylate products. Methyl glycolate was used as a raw material, mixed with oxygen and nitrogen. The reaction was carried out at a temperature of 205°C, a pressure of 0.2 MPa, and a methyl glycolate weight hourly space velocity of 2 h⁻¹. -1 Nitrogen volume hourly space velocity 3000 h⁻¹ -1 The glyoxylate product was synthesized under the condition of 0.3% oxygen molar content in the exhaust gas. The reaction results are shown in Table 2.

[0166] [Comparative Example 4]

[0167] Using 20g packaged methyl glyoxylate (from the Shanghai Test brand, purchased by Sinopharm Reagent) as raw material, and after multiple separations and purifications, glyoxylate esters as shown in Table 2 were obtained. The above product was used for the synthesis of ethyl α-hydroxy-4-phenyl-4-pentenoate. The reaction conditions were: using inexpensive and environmentally friendly ferric chloride as catalyst, a molar ratio of α-methylstyrene to ethyl glyoxylate of 1:1, a reaction temperature of 30℃, and a reaction time of 5h, the yield of ethyl α-hydroxy-4-phenyl-4-pentenoate was 48.7%.

[0168] Table 1

[0169]

[0170] Table 2

[0171]

[0172] *The others in the table are polymers.

[0173]

Example 12

[0174] The catalyst obtained in Example 1 was used to synthesize glyoxylate products. Experiments were conducted by changing the process conditions. The reaction conditions and results are shown in Table 3.

[0175]

Example 13

[0176] The glyoxylate obtained in [Example 12] was used for the synthesis of ethyl α-hydroxy-4-phenyl-4-pentenoate. The reaction conditions were as follows: ferric chloride, an inexpensive and environmentally friendly catalyst, was used; the molar ratio of α-methylstyrene to ethyl glyoxylate was 1:1; the reaction temperature was 30°C; and the reaction time was 5 h. The yield results of ethyl α-hydroxy-4-phenyl-4-pentenoate are shown in Table 3.

[0177] Table 3

[0178]

[0179] *The others in the table are polymers.

[0180] The specific embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combining the various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A glyoxylate product, characterized in that, By product mass, comprising: glycolate 0.03%~0.3%; oxalate monoester 0.03%~0.3%; acetal+hemiacetal 0.3%~1%; glyoxylate 79%~82.5%; polymer 0.3%~1.2%; water 16.5%~17.6%; The glycolate is methyl glycolate or ethyl glycolate; the glyoxylate is methyl glyoxylate or ethyl glyoxylate; the oxalate monoester is monomethyl oxalate or monoethyl oxalate; the acetal+hemiacetal is a condensate of glyoxylate and one or two molecules of methanol, ethanol or methyl glycolate, ethyl glycolate, and the structure is: ， R1 is an ester group, R2 and R3 are methyl, ethyl or an ester group; the polymer is a polymer of glycolic acid or glyoxylic acid.

2. The glyoxylate product of claim 1, wherein, Glyoxylate product, characterized by, by product mass, comprising: glycolate 0.07%~0.15%; oxalate monoester 0.07%~0.15%; acetal+hemiacetal 0.3%~0.6%; glyoxylate 80%~82%; polymer 0.3%~0.7%; water 16.8%~17.6%.

3. The glyoxylate product of claim 1, wherein, The platinum-cobalt color of the glyoxylate product is not higher than 70.

4. A process for the synthesis of a glyoxylate product according to any one of claims 1 to 3, characterized in that, Comprising the following steps: a) glycolate and oxygen-containing gas are contacted with a catalyst to perform an oxidation reaction, the reaction temperature is 170~230℃; the pressure is -0.5~1MPa; the liquid hourly space velocity of glycolate is 1.6~5h -1 ; b) the reaction product of step a) is subjected to gas-liquid separation, and the liquid phase is the glyoxylate product; The catalyst in step a) comprises, by weight fraction: a) 0.5~15 parts of active component copper, calculated as copper element; b) 0.1~10 parts of first auxiliary agent, calculated as element; c) 0.01~1 parts of second auxiliary agent, calculated as element; d) 84~99.39 parts of carrier; The catalyst is characterized by NH3-TPD test desorption peak existing in the range of 50℃~300℃; The molar ratio of the second auxiliary agent to the first auxiliary agent is 0.01~0.02; the first auxiliary agent is selected from at least one of iron, cobalt and manganese; and the second auxiliary agent is selected from at least one of potassium and barium.

5. The method of synthesis of claim 4, wherein, a) glycolate and oxygen-containing gas are contacted with a catalyst to perform an oxidation reaction, the reaction temperature is 180~220℃; the pressure is -0.5~0.5MPa; the liquid hourly space velocity of glycolate is 1.6~2h -1 .

6. The method of synthesis of claim 4, wherein, The mass content of alcohol impurities in the glycolate in step a) is less than 1%.

7. The method of synthesis of claim 4, wherein, The mass content of alcohol impurities in the glycolate in step a) is less than 0.3%.

8. The method of synthesis of claim 4, wherein, The oxygen-containing gas in step a) is a mixed gas of nitrogen and oxygen or nitrogen and air, and the volume space velocity of nitrogen in the oxygen-containing gas is 1000-4000 h -1 .

9. The method of synthesis of claim 4, wherein, The molar content of oxygen in the tail gas in the synthesis method is controlled to be 0.1%~1%.

10. The method of synthesis of claim 4, wherein, The molar content of oxygen in the tail gas in the synthesis method is controlled to be 0.2%~0.7%.

11. The method of synthesis of claim 4, wherein, The catalyst in step a) is characterized by NH3-TPD test, and the NH3-TPD acid amount in the range of 50℃~180℃ is more than 80% of the total NH3-TPD acid amount within 300℃.

12. The method of synthesis of claim 4, wherein, The catalyst in step a) is characterized by NH3-TPD test, and the NH3-TPD acid amount in the range of 50℃~180℃ is more than 90% of the total NH3-TPD acid amount within 300℃.

13. The method of synthesis of claim 4, wherein, The catalyst in step a) is characterized by NH3-TPD test, and the NH3-TPD acid amount in the range of 50℃~180℃ is more than 92% of the total acid amount within 300℃.

14. The method of synthesis of claim 4, wherein, The particles with a particle size distribution of 30-60nm account for more than 85% of the total number of carrier particles.

15. The method of synthesis of claim 4, wherein, The particles with a particle size distribution of 30-60nm account for 90%~95% of the total number of carrier particles.

16. The method of synthesis of claim 4, wherein, The catalyst is characterized by XRD test without obvious copper characteristic peaks at 2θ=50.4°, 2θ=74.1°, and without obvious copper oxide characteristic peaks at 2θ=29.7°, 36.6°, 42.4°, 61.5°, 73.7°, 77.6°.

17. The method of synthesis of claim 4, wherein The catalyst is characterized by H2-TPR test with only one hydrogen reduction peak of the active component Cu; the H2-TPR characterization data of the catalyst: Cu reduction peak temperature is 200℃±10℃.

18. The method of synthesis of claim 4, wherein The catalyst is characterized by H2-TPR test with only one hydrogen reduction peak of the active component Cu; the H2-TPR characterization data of the catalyst: Cu reduction peak temperature is 200℃±7℃.

19. The method of synthesis of claim 4, wherein, The catalyst is characterized by H2-TPR test with a temperature difference between the end position of hydrogen reduction of the active component Cu and the start position of the peak <60℃.

20. The method of synthesis of claim 4, wherein, The catalyst is characterized by H2-TPR test with a temperature difference between the end position of hydrogen reduction of the active component Cu and the start position of the peak <40℃.

21. The method of synthesis of claim 4, wherein, The catalyst is characterized by H2-TPR test with a temperature difference between the end position of hydrogen reduction of the active component Cu and the start position of the peak <30℃.

22. The method of synthesis of claim 4, wherein, The molar ratio of the first additive to the active component copper is 0.2-5.

23. The method of synthesis of claim 4, wherein, The molar ratio of the first additive to the active component copper is 0.3-4.

24. The method of synthesis of claim 4, wherein, The preparation method of the catalyst comprises the following steps: a) preparing a water solution of soluble salts of the active component and the first additive, and adjusting the pH value to 2-5; b) mixing the carrier powder with a low-carbon alcohol solution with a boiling point lower than 110℃ to obtain a slurry; c) adding the solution obtained in step a) to the slurry obtained in step b) under stirring; d) refluxing the slurry obtained in step c) at 50-100℃ for 2-20 hours, and adding the second additive during or after the heating; e) drying and heat-treating the slurry obtained in step d) to obtain the catalyst for synthesizing glyoxalate by oxidation method.

25. Use of the glyoxalate product of any one of claims 1-3 or the glyoxalate product synthesized by the method of any one of claims 4-24 in the synthesis of ethyl α-hydroxy-4-phenyl-4-pentenoate.

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