A process for utilizing waste from 1,4-bis(4-fluorobenzoyl)benzene production

Abstract

The application discloses a kind of 1,4-di (4-fluorobenzoyl) phenol production waste utilization process, it belongs to 1,4-di (4-fluorobenzoyl) phenol production technical field, including the following steps, waste scraps are dissolved in solvent and active carbon adsorption is removed pigment and solid particles in scrap material;The pretreated scrap material is subjected to dehalogenation hydrogenation under the condition of hydrogenation catalyst and alkaline substance, and 1,4-biphenyl acyl benzene is produced;The hydrogenation product is separated and purified using solution crystallization, and 1,4-biphenyl acyl benzene with a purity of 99.75% or more is obtained.The application uses waste scraps to produce 1,4-biphenyl acyl benzene, improves the utilization rate of raw materials, reduces the amount of hazardous waste emissions, and is green and environmentally friendly.

Description

Technical Field

[0001] This invention relates to the field of 1,4-bis(4-fluorobenzoyl)benzene production technology, and specifically to a process for utilizing waste from 1,4-bis(4-fluorobenzoyl)benzene production. Background Technology

[0002] PEEK materials possess a range of advantages, including high strength, high modulus, high temperature resistance, radiation resistance, and dimensional stability, making them widely used in aerospace, electronics, new energy vehicles, oil and gas exploration, and 3D printing. 1,4-Di(4-fluorobenzoyl)benzene, commonly known as triphenyl difluorodione, has a melting point of 220-222℃ and is the main monomer for synthesizing PEEK materials. Currently, it is primarily synthesized through a Friedel-Crafts acylation reaction of fluorobenzene with terephthaloyl chloride using a catalyst. However, a small amount of positional isomers of 1,4-di(4-fluorobenzoyl)benzene, such as 1-(2-fluorobenzoyl)-4-(4-fluorobenzoyl)benzene, is inevitably produced during the reaction. Solution crystallization is commonly used to purify 1,4-di(4-fluorobenzoyl)benzene to obtain a purity greater than 99.9%. The by-products from solution crystallization are mainly composed of a mixture of 1-(2-fluorobenzoyl)-4-(4-fluorobenzoyl)benzene and a small amount of 1,4-bis(4-fluorobenzoyl)benzene. Because 1-(2-fluorobenzoyl)-4-(4-fluorobenzoyl)benzene cannot be used as a raw material for the synthesis of PAEK materials, it is usually treated as hazardous waste, which has high treatment costs and causes resource waste.

[0003] 1,4-Biphenylylbenzene, with a melting point of 161-165℃, has wide applications in organic synthesis and is an important intermediate compound. It is often used as a starting material in the preparation of other organic compounds. It is commonly used in the synthesis of fluorescent dyes, photosensitive materials, organic optoelectronic materials, etc. How to prepare 1,4-biphenylylbenzene from the waste in the production of 1,4-bis(4-fluorobenzoyl)benzene and make full use of it to avoid resource waste is a problem that needs to be solved.

[0004] In view of the problems existing in the prior art, the present invention, combined with years of design and use experience in related fields, designs a process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene to overcome the above defects. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene. By controlling temperature and pressure, 1,4-bis(4-fluorobenzoyl)benzene and 1-(2-fluorobenzoyl)-4-(4-fluorobenzoyl)benzene are catalyzed under a hydrogenation catalyst to produce 1,4-biphenylylbenzene with high purity, which can be used to synthesize fluorescent dyes, photosensitive materials, organic optoelectronic materials, etc.

[0006] To achieve the above objectives, a first aspect of the present invention provides a process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene, comprising the following steps:

[0007] Step 1, solution crystallization: Dissolve the waste residue in a solvent, and add 1-3% activated carbon by mass of the waste residue. After keeping it warm, perform hot filtration to remove the activated carbon and other solid impurities from the solution. Cool the filtrate to room temperature and perform solid-liquid separation to obtain a mixture of triphenyl difluorodione position isomers.

[0008] Step 2, hydrodehalogenation reaction: Under a hydrogen atmosphere, the mixture of triphenyl difluorodione positional isomers from Step 1, the alkaline substance, the hydrogenation solvent and the hydrogenation catalyst are added to the reactor to carry out the hydrodehalogenation reaction. After the reaction is completed, the reactor is hot-filtered to separate the hydrogenation catalyst for reuse. The filtrate is cooled to room temperature, filtered, and the solid is washed with water until the washing liquid is neutral. The solid is then dried to obtain the crude product.

[0009] Step 3, solution crystallization: Dissolve the crude product in a crystallization solvent and recrystallize to obtain 1,4-biphenylylbenzene with a purity greater than or equal to 99.75%;

[0010] The waste materials include 1,4-bis(4-fluorobenzoyl)benzene and 1-(2-fluorobenzoyl)-4-(4-fluorobenzoyl)benzene.

[0011] Preferably, the solvent in step 1 is any one or a combination of several of ethanol, methanol, isopropanol, DMAC, DMSO, and DMF.

[0012] The hydrogenation solvent mentioned in step 2 is one of water, methanol, ethanol, toluene, and xylene.

[0013] Preferably, the heat preservation conditions in step 1 are 67-180℃ and 1 bar for 1-3 hours.

[0014] Preferably, in step 1, a ceramic membrane filter is used for thermal filtration, and the precision of the ceramic membrane filter is 10-20μm;

[0015] The filtrate from step 1 is cooled to room temperature at a rate of 30-60℃ / h.

[0016] Preferably, the alkaline substance in step 2 is any one of hydroxide, alkali metal carbonate, alkali metal bicarbonate, and organic amine.

[0017] Preferably, the mass ratio of the alkaline substance to the triphenyl difluorodione positional isomer mixture in step 2 is (0.45:1) to (2:1).

[0018] Preferably, the hydrogenation catalyst in step 2 is any one of palladium on carbon, Raney nickel, and platinum on carbon;

[0019] The palladium-on-carbon catalyst has a palladium loading of 5%, the platinum-on-carbon catalyst has a platinum loading of 3%, and the Raney nickel has an activity level of W-4.

[0020] In step 2, the amount of hydrogenation catalyst added is 5.wt%-30.wt% based on the mass of the triphenyl difluorodione positional isomer mixture.

[0021] Preferably, the amount of hydrogenation solvent added is 5-20 times the mass of the triphenyl difluorodione positional isomer mixture;

[0022] The conditions for the hydrogenation dehalogenation reaction are: a pressure of 0.5-1.5 MPa and a temperature of 80-120 °C for 12-24 h.

[0023] Preferably, in step 2, a ceramic membrane filter is used for thermal filtration, and the precision of the ceramic membrane filter is 10-20μm;

[0024] The filtrate from step 2 is cooled to room temperature at a rate of 30-40℃ / h.

[0025] Preferably, the crystallization solvent in step 3 is any one of cyclohexane, toluene, isobutyl carbonate, and DMAC.

[0026] The advantages of this invention are:

[0027] This invention addresses the treatment of waste materials generated during the production of 1,4-bis(4-fluorobenzoyl)benzene. First, activated carbon is used to remove solid impurities from the waste materials and simultaneously decolorize them. Then, a hydrogenation catalyst is used to carry out a hydrogenation dehalogenation reaction to produce 1,4-biphenylylbenzene. Finally, the product is purified by recrystallization, thereby realizing the utilization of waste materials, improving raw material utilization, reducing hazardous waste emissions, and being environmentally friendly. Attached Figure Description

[0028] Figure 1 This is a diagram illustrating the hydrogenation and dehalogenation reaction process of the triphenyl difluorodione positional isomer mixture in this invention.

[0029] Figure 2 This is the gas chromatogram of the crude product 1,4-biphenylylbenzene in Example 2 of the present invention;

[0030] Figure 3 This is a gas chromatogram of the 1,4-biphenylylbenzene solution after crystallization in Example 2 of the present invention. Detailed Implementation

[0031] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to specific embodiments.

[0032] This invention provides a process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene, comprising the following steps:

[0033] Step 1, solution crystallization: Dissolve the waste residue in a solvent, and add 1-3% activated carbon by mass of the waste residue. Keep the solution at 67-180℃ and 1 bar for 1-3 hours, then hot filter to obtain the filtrate. Remove the activated carbon and other solid impurities from the solution. Cool the filtrate to room temperature at a cooling rate of 30-60℃ / h and perform solid-liquid separation to obtain a mixture of triphenyl difluorodione position isomers.

[0034] Step 2, hydrodehalogenation reaction: Under a hydrogen atmosphere, the mixture of triphenyl difluorodione positional isomers from Step 1, the alkaline substance, the hydrogenation solvent, and the hydrogenation catalyst are added to a reaction vessel for hydrodehalogenation reaction. The pressure is 0.5-1.5 MPa, the temperature is 80-120℃, and the reaction time is 12-24 h. After the reaction is complete, the mixture is hot-filtered to separate the hydrogenation catalyst for reuse. The filtrate is cooled to room temperature at a rate of 30-40℃ / h, filtered, and the solid is washed with water until the washing liquid is neutral. The solid is then dried to obtain the crude product.

[0035] Step 3, solution crystallization: Dissolve the crude product in a crystallization solvent and recrystallize to obtain 1,4-biphenylylbenzene with a purity greater than or equal to 99.75%. The dissolution temperature is 80℃-165℃, the temperature holding time is 1-1.5h, the cooling rate is 10-30℃ / h, and the final cooling temperature is room temperature.

[0036] In this invention, the waste material originates from the Friedel-Crafts acylation reaction of fluorobenzene and terephthaloyl chloride to synthesize 1,4-bis(4-fluorobenzoyl)benzene. The waste material is purified by solution crystallization and mainly consists of 1-(2-fluorobenzoyl)-4-(4-fluorobenzoyl)benzene, a small amount of 1,4-bis(4-fluorobenzoyl)benzene, carbonized organic particles, polymers, and alumina particles. This invention first utilizes activated carbon to remove impurities and decolorize the waste material, thus initially improving the purity of the system to obtain a mixture of triphenyl difluorodione positional isomers. The triphenyl difluorodione positional isomer mixture includes 1-(2-fluorobenzoyl)-4-(4-fluorobenzoyl)benzene and 1,4-bis(4-fluorobenzoyl)benzene. Under strict control of the temperature and pressure of the reactor in the presence of a hydrogenation catalyst, the 1-(2-fluorobenzoyl)-4-(4-fluorobenzoyl)benzene and 1,4-bis(4-fluorobenzoyl)benzene undergo a hydrogenation-dehalogenation reaction to synthesize 1,4-biphenylylbenzene, which is then further purified by solution crystallization. This invention improves the utilization rate of raw materials for 1,4-bis(4-fluorobenzoyl)benzene production, reduces hazardous waste emissions, and is environmentally friendly. The 1,4-biphenylylbenzene obtained by this invention has high purity and can be used to synthesize fluorescent dyes, photosensitive materials, organic optoelectronic materials, etc. The hydrogenation-dehalogenation reaction process of the triphenyl difluorodione positional isomer mixture is as follows: Figure 1 As shown.

[0037] The solvent in step 1 is any one or a combination of several of ethanol, methanol, isopropanol, DMAC, DMSO, and DMF. The device for the hot filtration process is a ceramic membrane filter with a precision of 10-20 μm. The alkaline substance in step 2 is any one of hydroxides, alkali metal carbonates, alkali metal bicarbonates, and organic amines, and is added in liquid form. Preferably, it is any one of calcium hydroxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, triethylamine, and triethanolamine. The mass ratio of the alkaline substance to the triphenyl difluorodione position isomer mixture is (0.45:1) to (2:1). The hydrogenation catalyst is any one of palladium on carbon, Raney nickel, and platinum on carbon. The palladium loading in the palladium on carbon catalyst is 5%, the platinum loading in the platinum on carbon catalyst is 3%, and the Raney nickel has an activity level of W-4. Based on the mass of the triphenyl difluorodione positional isomer mixture, the amount of hydrogenation catalyst added is 5.wt%-30.wt%, and the amount of hydrogenation solvent added is 5-20 times the mass of the triphenyl difluorodione positional isomer mixture. The hydrogenation solvent in step 2 is one of water, methanol, ethanol, toluene, and xylene. Thermal filtration in step 2 is performed using a ceramic membrane filter with a precision of 10-20 μm. The crystallization solvent in step 3 is any one of cyclohexane, toluene, isobutyl carbonate, and DMAC.

[0038] Specific embodiments are shown below.

[0039] Unless otherwise specified, the experimental methods used in this invention are all conventional methods, and the materials and reagents used are all commercially available unless otherwise specified. Example 1:

[0040] Step 1, solution crystallization: Add 1000g of DMAC, 2g of activated carbon, and 100g of residue (containing 1,4-bis(4-fluorobenzoyl)benzene and 1-(2-fluorobenzoyl)-4-(4-fluorobenzoyl)benzene) to a three-necked flask. Heat to 165℃ and keep at 1 bar for 1h. Then, use a ceramic membrane filter (10μm precision) for hot filtration to remove activated carbon and small solid particles in the solution. Cool the filtrate at a rate of 50℃ / h. After cooling to room temperature, filter and dry to obtain 87g of a mixture of triphenyl difluorodione position isomers.

[0041] Step 2: Hydrogenation and dehalogenation reaction. Under a hydrogen atmosphere, 87g of the above mixture of triphenyl difluorodione positional isomers was added to a reactor, followed by 200g of 40% sodium hydroxide solution, 500g of xylene, and 4.4g of palladium on carbon catalyst (5% palladium loading). The reaction was carried out at 120℃ and 1.5MPa for 12h. After the reaction was completed, the reactor material was transferred to a ceramic membrane filter (10μm precision) to separate the palladium on carbon catalyst. The resulting filtrate was cooled to room temperature at a rate of 40℃ / h, filtered, and the solid was washed with water until the washing liquid was neutral. After drying, 75g of crude product 1,4-biphenylylbenzene was obtained, with a purity of 98.32%.

[0042] Step 3, solution crystallization: Add the above 75g crude product to the crystallization vessel, use isobutyl carbonate as the crystallization solvent, heat to 145℃ and keep warm for 1h, then cool the solution at a rate of 30℃ / h, filter and dry after cooling to room temperature to obtain 70g of 1,4-biphenylylbenzene with a purity of 99.75%. Example 2:

[0043] Step 1: Add 850g of DMSO, 1.5g of activated carbon, and 150g of residue (containing 1,4-bis(4-fluorobenzoyl)benzene and 1-(2-fluorobenzoyl)-4-(4-fluorobenzoyl)benzene) to a three-necked flask. Heat to 180℃ and maintain at 1 bar for 1.5h. Then transfer to a ceramic membrane filter (20μm precision) for hot filtration to remove activated carbon and small solid particles in the solution. Cool the obtained filtrate at a cooling rate of 60℃ / h. After cooling to room temperature, filter and dry to obtain 143g of a mixture of triphenyl difluorodione position isomers.

[0044] Step 2: Hydrogenation and dehalogenation reaction. Under a hydrogen atmosphere, 143g of the above mixture of triphenyl difluorodione positional isomers was added to a reactor, followed by 258g of 25% potassium hydroxide solution, 740g of ethanol, and 28.6g of platinum-carbon catalyst (3% platinum loading). The reaction was carried out at 100℃ and 1.5MPa for 24h. After the reaction was completed, the reactor contents were transferred to a ceramic membrane filter (20μm precision) to separate the platinum-carbon catalyst. The resulting filtrate was cooled to room temperature at a rate of 35℃ / h, filtered, and the solid was washed with water until the washing liquid was neutral. After drying, 118g of crude product 1,4-biphenylylbenzene was obtained, with a purity of 96.47%. See [link to relevant documentation]. Figure 2 ;

[0045] Step 3: Solution crystallization. Add 100g of the crude product to a crystallization vessel using cyclohexane as the crystallization solvent. Heat to 80℃ to dissolve, maintain this temperature for 1.5h, then cool the solution at a rate of 10℃ / h. After cooling to room temperature, filter and dry to obtain 97g of 1,4-biphenylylbenzene with a purity of 99.86%. See [link to relevant documentation]. Figure 3 . Example 3:

[0046] Step 1: Add 2000g of methanol, 3g of activated carbon, and 100g of residue (containing 1,4-bis(4-fluorobenzoyl)benzene and 1-(2-fluorobenzoyl)-4-(4-fluorobenzoyl)benzene) to a three-necked flask. Heat to 67°C and maintain at 1 bar for 3 hours. Then transfer to a ceramic membrane filter (10μm precision) for hot filtration to remove activated carbon and small solid particles in the solution. Cool the obtained filtrate at a cooling rate of 30°C / h. After cooling to room temperature, filter and dry to obtain 68g of a mixture of triphenyl difluorodione position isomers.

[0047] Step 2: Hydrogenation and dehalogenation reaction. Under a hydrogen atmosphere, 68g of the above mixture of triphenyl difluorodione positional isomers was added to a reaction vessel, followed by 128g of triethylamine, 1360g of methanol, and 20.4g of Raney nickel (activity grade W-4). The reaction was carried out at 80℃ and 0.5MPa for 18h. After the reaction was completed, the material in the reaction vessel was transferred to a ceramic membrane filter (10μm precision) to separate the Raney nickel. The resulting filtrate was cooled to room temperature at a rate of 30℃ / h, filtered, and the solid was washed with water until the washing liquid was neutral. After drying, 56.3g of crude product 1,4-biphenylylbenzene was obtained, with a purity of 98.23%.

[0048] Step 3, solution crystallization: Take 50g of the above crude product and add it to the crystallization vessel. Use DMAC as the crystallization solvent, heat to 165℃ to dissolve, keep warm for 1h, and then cool the solution at a cooling rate of 30℃ / h. After cooling to room temperature, filter and dry to obtain 46g of 1,4-biphenylylbenzene with a purity of 99.92%.

[0049] It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the invention. Furthermore, it should be understood that after reading the technical description of this invention, those skilled in the art can make various alterations, modifications, and / or variations to the invention, and all such equivalent forms also fall within the scope of protection defined by the appended claims.

Claims

1. A process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene, characterized in that, Includes the following steps: Step 1, solution crystallization: Dissolve the waste residue in a solvent, and add 1-3% activated carbon by mass of the waste residue. After keeping it warm, perform hot filtration to remove the activated carbon and other solid impurities from the solution. Cool the filtrate to room temperature and perform solid-liquid separation to obtain a mixture of triphenyl difluorodione position isomers. Step 2, hydrodehalogenation reaction: Under a hydrogen atmosphere, the mixture of triphenyl difluorodione positional isomers from Step 1, the alkaline substance, the hydrogenation solvent and the hydrogenation catalyst are added to the reactor to carry out the hydrodehalogenation reaction. After the reaction is completed, the reactor is hot-filtered to separate the hydrogenation catalyst for reuse. The filtrate is cooled to room temperature, filtered, and the solid is washed with water until the washing liquid is neutral. The solid is then dried to obtain the crude product. Step 3, solution crystallization: Dissolve the crude product in a crystallization solvent and recrystallize to obtain 1,4-biphenylylbenzene with a purity greater than or equal to 99.75%; The waste material comes from the waste material generated during the Friedel-Crafts acylation reaction of fluorobenzene and terephthaloyl chloride to synthesize 1,4-bis(4-fluorobenzoyl)benzene, and is purified by solution crystallization. The mixture of triphenyl difluorodione positional isomers includes 1-(2-fluorobenzoyl)-4-(4-fluorobenzoyl)benzene and 1,4-bis(4-fluorobenzoyl)benzene; The hydrogenation catalyst mentioned in step 2 is any one of palladium on carbon, Raney nickel, and platinum on carbon; The palladium-on-carbon catalyst has a palladium loading of 5%, the platinum-on-carbon catalyst has a platinum loading of 3%, and the Raney nickel has an activity grade of W-4; the amount of hydrogenation catalyst added is 5.wt%-30.wt% based on the mass of the triphenyl difluorodione position isomer mixture. The conditions for the hydrogenation dehalogenation reaction are: a pressure of 0.5-1.5 MPa and a temperature of 80-120 °C for 12-24 h.

2. The process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene according to claim 1, characterized in that, The solvent in step 1 is any one or a combination of several of ethanol, methanol, isopropanol, DMAC, DMSO, and DMF; The hydrogenation solvent mentioned in step 2 is one of water, methanol, ethanol, toluene, and xylene.

3. The process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene according to claim 1, characterized in that, The insulation conditions in step 1 are 67-180℃ and 1 bar for 1-3 hours.

4. The process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene according to claim 1, characterized in that, In step 1, a ceramic membrane filter is used for thermal filtration. The precision of the ceramic membrane filter is 10-20μm. The filtrate from step 1 is cooled to room temperature at a rate of 30-60℃ / h.

5. The process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene according to claim 1, characterized in that, The alkaline substance mentioned in step 2 is any one of hydroxides, alkali metal carbonates, alkali metal bicarbonates, and organic amines.

6. The process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene according to claim 1, characterized in that, The mass ratio of the alkaline substance to the triphenyl difluorodione positional isomer mixture in step 2 is (0.45:1) - (2:1).

7. The process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene according to claim 1, characterized in that, The amount of hydrogenated solvent added is 5-20 times the mass of the triphenyl difluorodione positional isomer mixture.

8. The process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene according to claim 1, characterized in that, In step 2, a ceramic membrane filter is used for thermal filtration. The precision of the ceramic membrane filter is 10-20μm. The filtrate from step 2 is cooled to room temperature at a rate of 30-40℃ / h.

9. The process for utilizing waste from the production of 1,4-bis(4-fluorobenzoyl)benzene according to claim 1, characterized in that, The crystallization solvent in step 3 is any one of cyclohexane, toluene, isobutyl carbonate, and DMAC.

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