Environment-friendly p-hydroxyacetophenone production process

Abstract

The invention discloses an environment-friendly p-hydroxyacetophenone production process, and particularly relates to the technical field of p-hydroxyacetophenone production, which comprises the following steps: step 1, respectively putting dissolved phenol and acetic anhydride into a synthesis reaction kettle, stirring and heating to 128 DEG C, refluxing for 5 hours at normal pressure, then carrying out heat preservation treatment, and reacting to generate phenyl acetate; 2, cooling phenyl acetate generated by the reaction to 60 DEG C, washing with water, standing for layering, and discharging phenyl acetate to generate a small amount of by-products containing 90% of glacial acetic acid; and 3, pumping the dehydrated phenyl acetate into a reaction kettle by a vacuum pump, gradually adding aluminum trichloride, then adding acidic water for hydrolysis, cooling to 60 DEG C, and discharging to obtain a liquid crude product of p-hydroxyacetophenone and o-hydroxyacetophenone. The environment-friendly performance of implementation is good, conditions needed by the technology are mild, the unstable condition is not prone to occurring in the operation process, and the practical application effect of the method is ideal.

Description

Technical Field

[0001] The present invention relates to the technical field of p - hydroxyacetophenone production, and more specifically, to an environmentally friendly production process for p - hydroxyacetophenone. Background Art

[0002] p - Hydroxyacetophenone, also known as 4 - hydroxyacetophenone and commonly called piceol, is a white needle - shaped crystal at room temperature, flammable, soluble in hot water, methanol, ethanol, ether, acetone, benzene, and insoluble in petroleum ether. In the implementation of the existing p - hydroxyacetophenone production process, its environmental friendliness is not good enough, and the conditions required by the process are not mild enough, and instability is likely to occur during the operation process, resulting in an unsatisfactory actual application effect of the existing p - hydroxyacetophenone production process.

[0003] Therefore, there is an urgent need for an environmentally friendly production process for p - hydroxyacetophenone. Summary of the Invention

[0004] To overcome the above - mentioned defects of the prior art, an embodiment of the present invention provides an environmentally friendly production process for p - hydroxyacetophenone. The embodiment of the present invention has good environmental friendliness, the conditions required by the process are relatively mild, and instability is not likely to occur during the operation process, making the actual application effect of the present invention relatively ideal, so as to solve the problems raised in the above - mentioned background art.

[0005] To achieve the above object, the present invention provides the following technical solution: An environmentally friendly production process for p - hydroxyacetophenone, comprising the following steps:

[0006] Step 1: Put melted phenol and acetic anhydride into a synthesis reaction kettle respectively, stir and heat up to 128 °C, reflux at normal pressure for 5 hours, and then carry out heat preservation treatment to react to form phenyl acetate;

[0007] Step 2: After the phenyl acetate generated by the reaction is cooled to 60 °C, it is washed with water, allowed to stand for separation, and the phenyl acetate is discharged, generating a small amount of by - product glacial acetic acid containing 90%;

[0008] Step 3: The dehydrated phenyl acetate is pumped into a conversion reaction kettle by a vacuum pump, aluminum trichloride is gradually added, and then hydrolyzed with acidic water. After cooling to 60 °C, the material is discharged to obtain a crude liquid of p - hydroxyacetophenone and o - hydroxyacetophenone;

[0009] Step 4: Freeze to below - 10 °C, heat up and stir for decolorization in a decolorization kettle, filter to discharge p - hydroxyacetophenone, dry to obtain the finished product of p - hydroxyacetophenone, and filter to produce waste activated carbon, and recycle the waste activated carbon;

[0010] Step 5: Weigh and package the finished product of p - hydroxyacetophenone;

[0011] Step 6: Feed the crude o-hydroxyacetophenone into a vacuum condenser, and then transfer the crude product to a distillation kettle for rectification. Distill o-hydroxyacetophenone at 125°C under reduced pressure.

[0012] Step 7: Fill the distilled o-hydroxyacetophenone into barrels for packaging.

[0013] In a preferred embodiment, the time for the heat preservation treatment in Step 1 is controlled at 7 hours.

[0014] In a preferred embodiment, the hydrolysis temperature in Step 3 is controlled between 95°C and 100°C.

[0015] The technical effects and advantages of the present invention:

[0016] In the present invention, molten phenol and acetic anhydride are respectively put into a synthesis reaction kettle, stirred and heated to 128°C, and refluxed at atmospheric pressure for 5 hours. Then, heat preservation treatment is carried out, and the time for the heat preservation treatment is controlled at 7 hours. Phenyl acetate is generated by the reaction. After the generated phenyl acetate is cooled to 60°C, it is washed with water, allowed to stand for stratification, and the phenyl acetate is discharged, producing a small amount of by-product glacial acetic acid containing 90%. The dehydrated phenyl acetate is pumped into a reaction kettle by a vacuum pump, aluminum trichloride is gradually added, and then hydrolyzed with acidic water. The hydrolysis temperature is controlled between 95°C and 100°C. After cooling to 60°C, the liquid crude products of p-hydroxyacetophenone and o-hydroxyacetophenone are discharged. After freezing to below -10°C, stirring and decolorization are carried out in a decolorization kettle while heating. The p-hydroxyacetophenone is filtered and discharged, and then dried to obtain the finished product of p-hydroxyacetophenone. Waste activated carbon is generated during filtration, and the waste activated carbon is recycled. The finished product of p-hydroxyacetophenone is weighed and packaged. The crude o-hydroxyacetophenone is fed into a vacuum condenser, and the crude product is transferred to a distillation kettle for rectification. Distill o-hydroxyacetophenone at 125°C under reduced pressure. The distilled o-hydroxyacetophenone is filled into barrels for packaging. The present invention has good environmental protection performance, the required conditions of the process are relatively mild, and it is not easy to appear unstable situations during the operation process, so that the actual application effect of the present invention is relatively ideal. Specific embodiments

[0017] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0018] Example 1

[0019] The present invention provides an environmentally friendly production process for p-hydroxyacetophenone, including the following steps:

[0020] Step 1: Put the melted phenol and acetic anhydride into the synthesis reactor respectively, stir and heat up to 128°C, reflux at atmospheric pressure for 5 hours, and then carry out heat preservation treatment to react to produce phenyl acetate;

[0021] Step 2: After the produced phenyl acetate is cooled to 60°C, carry out water washing, stand for stratification, discharge the phenyl acetate, and produce a small amount of by-product glacial acetic acid containing 90%;

[0022] Step 3: The dehydrated phenyl acetate is pumped into the reaction kettle by a vacuum pump, aluminum trichloride is gradually added, and then hydrolyzed with acidic water. After cooling to 60°C, the crude liquid of p-hydroxyacetophenone and o-hydroxyacetophenone is discharged;

[0023] Step 4: Freeze to below -10°C, heat up and stir for decolorization in the decolorization kettle, filter and discharge p-hydroxyacetophenone, dry to obtain the finished product of p-hydroxyacetophenone, filter to produce waste activated carbon, and recycle the waste activated carbon;

[0024] Step 5: Weigh and package the finished product of p-hydroxyacetophenone;

[0025] Step 6: Feed the crude o-hydroxyacetophenone into the vacuum condenser and rectify the crude product to the rectification kettle. Distill out o-hydroxyacetophenone at 125°C under reduced pressure;

[0026] Step 7: Fill the distilled o-hydroxyacetophenone into drums for packaging.

[0027] In Step 1, the time of heat preservation treatment is controlled within 7 hours.

[0028] In Step 3, the hydrolysis temperature is controlled at 95°C.

[0029] In this example, it is stirred and heated up to 128°C, refluxed at atmospheric pressure for 5 hours. After the produced phenyl acetate is cooled to 60°C, water washing is carried out, and the hydrolysis temperature is controlled at 95°C. Compared with the prior art, this example has better environmental protection, milder process conditions required, and more stable operation process.

[0030] Example 2

[0031] The present invention provides an environmentally friendly production process of p-hydroxyacetophenone, including the following steps:

[0032] Step 1: Put the melted phenol and acetic anhydride into the synthesis reactor respectively, stir and heat up to 128°C, reflux at atmospheric pressure for 5 hours, and then carry out heat preservation treatment to react to produce phenyl acetate;

[0033] Step 2: After the produced phenyl acetate is cooled to 60°C, carry out water washing, stand for stratification, discharge the phenyl acetate, and produce a small amount of by-product glacial acetic acid containing 90%;

[0034] Step 3: The dehydrated phenyl acetate is pumped into a reaction kettle by a vacuum pump, aluminum trichloride is gradually added, and then hydrolyzed with acidic water. After cooling to 60°C, the crude liquid of p-hydroxyacetophenone and o-hydroxyacetophenone is obtained by discharging the material;

[0035] Step 4: Freeze to below -10°C, raise the temperature in the decolorization kettle for stirring and decolorization, filter to discharge p-hydroxyacetophenone, dry to obtain the finished product of p-hydroxyacetophenone, waste activated carbon is generated during filtration, and the waste activated carbon is recycled;

[0036] Step 5: Weigh and package the finished product of p-hydroxyacetophenone;

[0037] Step 6: The crude o-hydroxyacetophenone is fed into a vacuum condenser, and the crude product is rectified in a rectification kettle. o-Hydroxyacetophenone is distilled out at 125°C under reduced pressure;

[0038] Step 7: The distilled o-hydroxyacetophenone is filled into barrels for packaging.

[0039] In Step 1, the time for heat preservation treatment is controlled at 7 hours.

[0040] In Step 3, the hydrolysis temperature is controlled at 96°C.

[0041] In this example, the temperature is raised to 128°C with stirring, refluxed at normal pressure for 5 hours, the generated phenyl acetate is cooled to 60°C and then washed with water, and the hydrolysis temperature is controlled at 96°C. Compared with the prior art, this example has better environmental protection, milder process conditions required, and more stable operation process.

[0042] Example 3

[0043] The present invention provides an environmentally friendly production process for p-hydroxyacetophenone, including the following steps:

[0044] Step 1: Put the melted phenol and acetic anhydride into the synthesis reaction kettle respectively, raise the temperature with stirring to 128°C, reflux at normal pressure for 5 hours, and then carry out heat preservation treatment to react to generate phenyl acetate;

[0045] Step 2: After the generated phenyl acetate is cooled to 60°C, it is washed with water, allowed to stand and separate layers, the phenyl acetate is discharged, and a small amount of by-product of glacial acetic acid containing 90% is generated;

[0046] Step 3: The dehydrated phenyl acetate is pumped into a reaction kettle by a vacuum pump, aluminum trichloride is gradually added, and then hydrolyzed with acidic water. After cooling to 60°C, the crude liquid of p-hydroxyacetophenone and o-hydroxyacetophenone is obtained by discharging the material;

[0047] Step 4: Freeze to below -10°C, raise the temperature in the decolorization kettle for stirring and decolorization, filter to discharge p-hydroxyacetophenone, dry to obtain the finished product of p-hydroxyacetophenone, waste activated carbon is generated during filtration, and the waste activated carbon is recycled;

[0048] Step 5: Weigh and package the p - hydroxyacetophenone finished product;

[0049] Step 6: Feed the crude o - hydroxyacetophenone into a vacuum condenser, and then transfer the crude product to a distillation kettle for distillation. Distill o - hydroxyacetophenone at 125°C under reduced pressure;

[0050] Step 7: Fill the distilled o - hydroxyacetophenone into drums for packaging.

[0051] The time for heat preservation treatment in Step 1 is controlled at 7 hours.

[0052] The hydrolysis temperature in Step 3 is controlled at 97°C.

[0053] In this example, the mixture is stirred and heated to 128°C, refluxed at atmospheric pressure for 5 hours. After the reaction - generated phenyl acetate is cooled to 60°C, it is washed with water. The hydrolysis temperature is controlled at 97°C. Compared with the prior art, this example has better environmental protection, milder process conditions, and a more stable operation process.

[0054] Example 4

[0055] The present invention provides an environmentally - friendly production process for p - hydroxyacetophenone, comprising the following steps:

[0056] Step 1: Put the melted phenol and acetic anhydride into a synthesis reaction kettle respectively, stir and heat to 128°C, reflux at atmospheric pressure for 5 hours, and then conduct heat preservation treatment to react and generate phenyl acetate;

[0057] Step 2: After the reaction - generated phenyl acetate is cooled to 60°C, wash it with water, let it stand for stratification, and release the phenyl acetate to produce a small amount of by - product of glacial acetic acid containing 90%;

[0058] Step 3: The dehydrated phenyl acetate is pumped into a reaction kettle by a vacuum pump, aluminum trichloride is gradually added, and then hydrolyzed with acidic water. After cooling to 60°C, discharge to obtain liquid crude products of p - hydroxyacetophenone and o - hydroxyacetophenone;

[0059] Step 4: Freeze to below - 10°C, heat up and stir for decolorization in a decolorization kettle, filter and release the p - hydroxyacetophenone, dry it to obtain the p - hydroxyacetophenone finished product, filter to produce waste activated carbon, and recycle the waste activated carbon;

[0060] Step 5: Weigh and package the p - hydroxyacetophenone finished product;

[0061] Step 6: Feed the crude o - hydroxyacetophenone into a vacuum condenser, and then transfer the crude product to a distillation kettle for distillation. Distill o - hydroxyacetophenone at 125°C under reduced pressure;

[0062] Step 7: Fill the distilled o - hydroxyacetophenone into drums for packaging.

[0063] The time for heat preservation treatment in Step 1 is controlled at 7 hours.

[0064] In Step 3, the hydrolysis temperature is controlled at 98°C.

[0065] In this example, the mixture is stirred and heated to 128°C, refluxed under normal pressure for 5 hours. After the generated phenyl acetate is cooled to 60°C, it is washed with water, and the hydrolysis temperature is controlled at 98°C. Compared with the prior art, this example has better environmental protection, milder process requirements, and a more stable operation process.

[0066] Example 5

[0067] The present invention provides an environmentally friendly production process for p-hydroxyacetophenone, comprising the following steps:

[0068] Step 1: Melted phenol and acetic anhydride are respectively put into a synthesis reaction kettle, stirred and heated to 128°C, refluxed under normal pressure for 5 hours, and then subjected to heat preservation treatment to generate phenyl acetate.

[0069] Step 2: After the generated phenyl acetate is cooled to 60°C, it is washed with water, allowed to stand for separation, and the phenyl acetate is discharged, producing a small amount of by-product glacial acetic acid containing 90%.

[0070] Step 3: The dehydrated phenyl acetate is pumped into a reaction kettle by a vacuum pump, aluminum trichloride is gradually added, and then hydrolyzed with acidic water. After cooling to 60°C, the crude liquid of p-hydroxyacetophenone and o-hydroxyacetophenone is discharged.

[0071] Step 4: Cool to below -10°C, heat up and stir for decolorization in a decolorization kettle, filter to discharge p-hydroxyacetophenone, dry it to obtain the finished product of p-hydroxyacetophenone, and recover the waste activated carbon generated by filtration.

[0072] Step 5: Weigh and package the finished product of p-hydroxyacetophenone.

[0073] Step 6: The crude o-hydroxyacetophenone is fed into a vacuum condenser and then rectified in a rectification kettle. o-Hydroxyacetophenone is distilled out at 125°C under reduced pressure.

[0074] Step 7: Package the distilled o-hydroxyacetophenone into drums.

[0075] In Step 1, the time of heat preservation treatment is controlled at 7 hours.

[0076] In Step 3, the hydrolysis temperature is controlled at 99°C.

[0077] In this example, the mixture is stirred and heated to 128°C, refluxed under normal pressure for 5 hours. After the generated phenyl acetate is cooled to 60°C, it is washed with water, and the hydrolysis temperature is controlled at 99°C. Compared with the prior art, this example has better environmental protection, milder process requirements, and a more stable operation process.

[0078] Example 6

[0079] The present invention provides an environmentally friendly production process for p - hydroxyacetophenone, comprising the following steps:

[0080] Step 1: Put the melted phenol and acetic anhydride into the synthesis reaction kettle respectively, stir and heat up to 128 °C, reflux at normal pressure for 5 hours, and then carry out heat preservation treatment to react to produce phenyl acetate;

[0081] Step 2: After the produced phenyl acetate is cooled to 60 °C, carry out water washing, stand for stratification, discharge the phenyl acetate, and produce a small amount of by - product glacial acetic acid containing 90%;

[0082] Step 3: The dehydrated phenyl acetate is pumped into the conversion reaction kettle by a vacuum pump, aluminum trichloride is gradually added, and then hydrolyzed with acidic water. After cooling to 60 °C, discharge to obtain crude liquid of p - hydroxyacetophenone and o - hydroxyacetophenone;

[0083] Step 4: Freeze to below - 10 °C, heat up and stir for decolorization in the decolorization kettle, filter and discharge p - hydroxyacetophenone, dry to obtain the finished product of p - hydroxyacetophenone, filter to produce waste activated carbon, and recycle the waste activated carbon;

[0084] Step 5: Weigh and package the finished product of p - hydroxyacetophenone;

[0085] Step 6: Feed the crude o - hydroxyacetophenone into the vacuum condenser and rectify the crude product to the rectification kettle. Distill out o - hydroxyacetophenone at 125 °C under reduced pressure;

[0086] Step 7: Fill and package the distilled o - hydroxyacetophenone into drums.

[0087] The time of heat preservation treatment in Step 1 is controlled within 7 hours.

[0088] The hydrolysis temperature in Step 3 is controlled at 100 °C.

[0089] In this embodiment, stir and heat up to 128 °C, reflux at normal pressure for 5 hours, carry out water washing after the produced phenyl acetate is cooled to 60 °C, and control the hydrolysis temperature at 100 °C. Compared with the prior art, this embodiment has better environmental protection, milder process conditions, and more stable operation process.

[0090] In the present invention, molten phenol and acetic anhydride are respectively put into a synthesis reaction kettle, stirred and heated to 128 °C, refluxed under normal pressure for 5 hours, and then subjected to heat preservation treatment. The heat preservation treatment time is controlled at 7 hours. Phenyl acetate is generated by the reaction. After the generated phenyl acetate is cooled to 60 °C, it is washed with water, allowed to stand and separate layers, and the phenyl acetate is discharged, producing a small amount of by-product glacial acetic acid containing 90%. The dehydrated phenyl acetate is pumped into a reaction kettle by a vacuum pump, aluminum trichloride is gradually added, and then hydrolyzed with acidic water. The hydrolysis temperature is controlled between 95 °C and 100 °C. After cooling to 60 °C, the material is discharged to obtain a crude liquid of p-hydroxyacetophenone and o-hydroxyacetophenone. It is frozen to below -10 °C, and stirred and decolorized by heating in a decolorization kettle. The p-hydroxyacetophenone is filtered and discharged, dried to obtain the finished product of p-hydroxyacetophenone. Waste activated carbon is generated by filtration, the waste activated carbon is recycled, the finished product of p-hydroxyacetophenone is weighed and packaged, and the crude o-hydroxyacetophenone is fed into a vacuum condenser and rectified in a rectification kettle. The o-hydroxyacetophenone is distilled out at 125 °C under reduced pressure, and the distilled o-hydroxyacetophenone is filled into barrels and packaged. The present invention has good environmental protection performance, the process conditions required are relatively mild, and unstable conditions are not likely to occur during the operation process, making the actual application effect of the present invention relatively ideal.

[0091] Finally: The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An environmentally friendly production process of p-hydroxyacetophenone, characterized in that, It includes the following steps: Step 1: Put the melted phenol and acetic anhydride into the synthesis reactor respectively, stir and heat up to 128 °C, reflux under normal pressure for 5 hours, and then carry out heat preservation treatment to react to produce phenyl acetate; Step 2: After the produced phenyl acetate is cooled to 60 °C, it is washed with water, allowed to stand and separate layers, and the phenyl acetate is discharged to produce a small amount of by-product glacial acetic acid containing 90%; Step 3: The dehydrated phenyl acetate is pumped into the conversion reactor by a vacuum pump, aluminum trichloride is gradually added, and then it is hydrolyzed with acidic water. After cooling to 60 °C, the crude liquid of p-hydroxyacetophenone and o-hydroxyacetophenone is discharged; Step 4: Cool to below -10 °C, heat up and stir for decolorization in the decolorization kettle, filter and discharge p-hydroxyacetophenone, dry it to obtain the finished product of p-hydroxyacetophenone, filter to produce waste activated carbon, and recycle the waste activated carbon; Step 5: Weigh and package the finished product of p-hydroxyacetophenone; Step 6: Feed the crude o-hydroxyacetophenone into the vacuum condenser and rectify the crude product to the rectification kettle. Distill out o-hydroxyacetophenone at 125 °C under reduced pressure; Step 7: Drum-pack the distilled o-hydroxyacetophenone.

2. The environmentally friendly production process of 4 - hydroxyacetophenone according to claim 1, characterized in that: The time of the heat preservation treatment in Step 1 is controlled within 7 hours.

3. An environmentally friendly production process of 4-hydroxyacetophenone according to claim 1, characterized in that: The hydrolysis temperature in Step 3 is controlled between 95 °C and 100 °C.