CN103086865B - Treatment method of perfluoroalkyl acyl fluoride waste - Google Patents

Abstract

The invention discloses a method for treating perfluoroalkyl acyl fluoride waste, which comprises the following steps: firstly adding an alkali solution to the perfluoroalkyl acyl fluoride waste for reaction, adjusting the pH value to 7-8, standing, The water phase and the oil phase are obtained by separation; the perfluorocarboxylate is obtained by separation and purification from the water phase; finally, the inert fluorocarbon is obtained by separation and purification from the oil phase. The invention separates perfluoroalkyl acid fluoride waste into water phase and oil phase by adding alkali solution, and separates and purifies the water phase and oil phase respectively, and obtains high-purity perfluorocarboxylic acid after the water phase is separated and purified The salt and oil phases are separated and purified to obtain high-purity inert fluorocarbons, which realizes the graded utilization of perfluoroalkyl fluoride wastes, with mild treatment conditions and good treatment effects.

Description

A kind of treatment method of perfluoroalkyl fluoride waste

technical field

The invention relates to the technical field of waste treatment produced in the electrochemical fluorination production process, in particular to a treatment method for perfluoroalkyl fluoride waste.

Background technique

At present, the Simons method is mostly used for the production of acyl fluoride products. First, perfluorocyclohexyl fluoride is produced by electrochemical fluorination of benzoyl chloride, and then the crude product of acyl fluoride is separated by distillation and purification. Some low-boiling perfluorinated compounds (PFCs) separated by rectification have a boiling point between 40 and 80 °C. That is, perfluoroalkyl fluoride waste. Perfluoroalkyl fluoride waste contains part of perfluorocyclohexyl fluoride, and other by-products, including other configurations of perfluoroacyl fluoride and inert fluorocarbons (perfluorocarbons and perfluorocyclic ethers mixture), etc.

The structure of perfluoroalkyl fluoride waste is quite stable, and it is an important organic chemical, in which inert fluorocarbons can be used as solvents, dielectrics, heat exchangers and hydraulic oils. Perfluoroacyl fluoride can be used to synthesize perfluoroacyl peroxide. Perfluoroalkyl acyl peroxides can be used as initiators to prepare tetrafluoroethylene (TFE)/hexafluoropropylene (HFP) polymers, which have good thermal stability and mechanical and physical properties, and can be used to process cable insulation films, pipes, etc. , fiber, board, and powder coating, etc.

But at the same time, perfluoroalkyl fluoride wastes are bioaccumulative and toxic, so they need to be properly treated. At present, the method of treating perfluoroalkyl fluoride wastes is mainly the direct combustion method, and the combustion product HF is recovered. This method requires an extremely high temperature above 1400 °C, which is accompanied by many disadvantages, such as high energy consumption, and the HF produced by decomposition will cause severe corrosion to the combustion device and reduce the durability of the system. Perfluoroalkyl fluoride wastes may contain more valuable or potential application value substances, so more consideration should be given to recycling methods.

Through gas chromatography-mass spectrometry, NMR and other means, it is found that perfluoroalkyl fluoride wastes contain trace amounts of highly fluorine-substituted hydrogen-containing substances and unsaturated perfluorocarbons, and the physical and chemical properties of these substances are similar to those of The target products are similar and cannot be separated directly by rectification. Highly fluorine-substituted hydrogen-containing substances and unsaturated perfluorocarbons contain unstable fluoride ions such as >CHF, >CF=CF<, which may release hydrogen fluoride during the use of inert fluorocarbon products Acids and unsaturated substances, which are toxic and must be removed.

The methods for removing highly fluorine-substituted hydrogen-containing substances and unsaturated perfluorocarbons are mainly divided into three categories. The first category of methods mainly destroys impurities without damaging the perfluorinated target products.

For example: U.S. Patent US3004075, published on October 10, 1961, discloses that it is purified by reagents such as ethanolamine or diethylamine, and produced by thermal polymerization of unsaturated olefins such as perfluoroethylene or thermal decomposition of highly fluorine-substituted substances. C2~C6 perfluoroalkanes, remove the perfluoroalkenes and highly fluorine-substituted hydrogen-containing substances contained in them.

U.S. Patent No. 5,563,306 published on January 21, 1993 discloses the use of nucleophiles (especially secondary amines, alkoxide ions) and high-concentration alkalis (especially KOH, NaOH) in the presence of Ca ²⁺ , Ba ²⁺ Purification of perfluorocarbons under ionic conditions is suitable for the production of perfluorocarbons by known methods such as electrochemical fluorination, indirect fluorination of CoF ₃ or direct fluorination of fluorine gas, etc., which can completely remove hydrogen-containing impurities and unsaturated perfluorocarbons. Fluorocarbon. The purified saturated perfluorocarbon can be directly used in medicine, biology and electronic technology.

U.S. Patent No. 2,999,885, published on September 12, 1961, discloses the use of a certain concentration of KMnO ₄ and alkali (KOH, NaOH) to treat unsaturated olefin thermal polymerization methods such as perfluoroethylene or thermal decomposition of highly fluorine-substituted substances. C2~C6 perfluoroalkanes produced by this method. Oxidative decomposition of unreacted reactants in perfluorocarbon products and impurities containing hydrogen and chlorine elements and unsaturated substances in products. The specific method is to use potassium permanganate with a mass fraction of about 5%~40%, and at the same time add alkali in proportion, add about 0.5~2 units of alkali (KOH, NaOH) per unit mass of potassium permanganate, and add a certain amount at the same time 0.5%~1% of surfactant, react at 20℃~95℃. However, the reaction needs to be operated at a pressure above 13 to 15 atmospheres, so special alloys are needed to make the reactor. The large consumption of expensive reaction materials and the considerable amount of material produced hinders the commercialization of this process.

U.S. Patent No. 4,766,261 published on August 23, 1988 discloses the use of strong bases or alkaline earth metals to remove hydrogen-containing substances in perfluorocarbons. Use 85% KOH (containing 15% H ₂ O), heat while stirring until the temperature rises to 170°C~175°C, the process takes about 1h. During this heating, the contents of the reactor changed from a white solid to an amber slurry and finally dark brown or black. When reflux begins to occur, keep at 90°C for 2h. Subsequently, a certain amount of water was slowly added to completely dissolve the unreacted KOH. The aqueous and organic phases are separated.

The second type of method is the adsorption method. The adsorbents include silica, alumina, activated carbon, alumina, zeolite, etc. This method is used to selectively remove reactive substances.

The third method is to co-distill the target product with a carrier (such as water, alcohol, etc.).

Dmitrii D. Moldavsky et al. studied the reaction of elemental fluorine with crude perfluorinated compounds in the presence of different catalysts in J. Fluor. Chem, 1998, (87): 111-121. Finally, CoF ₃ is selected as the catalyst, and the steam of the PFOC crude product and the gas fluorine-nitrogen mixture are introduced into the reactor, and the process is carried out until the fluorine is slightly excessive. Subsequently, the reaction mixture was reacted with aqueous sodium iodide. Finally, it is dried by distillation and washed with water.

Contents of the invention

The invention provides a treatment method for perfluoroalkyl acyl fluoride waste, which is aimed at the recycling and utilization of perfluoroalkyl acyl fluoride waste generated in the production process of perfluorocyclohexane acyl fluoride. The treatment conditions of the invention are mild , most of the perfluorinated compounds can be recovered, and the graded utilization of perfluoroalkyl fluoride waste can be realized, which effectively reduces the discharge of perfluoroalkyl fluoride waste.

A method for treating perfluoroalkyl fluoride wastes, comprising the following steps:

(1) adding an alkali solution to the perfluoroalkyl fluoride waste to react, adjusting the pH value to 7-8, standing still, and separating to obtain a water phase and an oil phase;

(2) Separating and purifying from the aqueous phase to obtain perfluorocarboxylate;

(3) Separation and purification from the oil phase to obtain inert fluorocarbons.

The source of perfluoroalkyl fluoride waste in the present invention is as follows:

Undecafluorocyclohexyl fluoride is produced by electrochemical fluorination of benzoyl chloride in liquid hydrogen fluoride under the condition of electrolytic additives. Due to the complex mechanism of electrochemical fluorination, in addition to the target product undecafluorocyclohexyl fluoride, a series of by-products may also be generated, mainly perfluoroalkyl acid fluorides of different configurations, perfluoroalkanes, Perfluoroethers, perfluoroolefins, a small amount of hydrogen-containing compounds and polymer compounds such as resin compounds. Therefore, in order to obtain the target acyl fluoride product, a fraction of the crude acyl fluoride product is collected first by rectification to separate part of the substance with a lower boiling point. This part of the substance with a lower boiling point is called perfluoroalkyl fluoride waste.

According to the preliminary analysis, in addition to some target acid fluorides, the perfluoroalkyl acid fluoride wastes also include isomeric perfluoroalkyl acid fluorides, inert fluorocarbons (perfluorocarbons, perfluorocyclic ethers), a small amount of HF and other hydrogen-containing compounds, etc.

The invention separates perfluoroalkyl acid fluoride waste into water phase and oil phase by adding alkali solution, and separates and purifies the water phase and oil phase respectively, and obtains high-purity perfluorocarboxylic acid after the water phase is separated and purified The salt and oil phases are separated and purified to obtain high-purity inert fluorocarbons, which realizes the graded utilization of perfluoroalkyl fluoride wastes, with mild treatment conditions and good treatment effects.

In step (1), the alkaline solution is at least one of potassium hydroxide solution, sodium hydroxide solution, potassium carbonate solution, sodium carbonate solution, sodium bicarbonate solution and potassium bicarbonate solution. Preferably, the alkaline solution is potassium carbonate solution or sodium carbonate solution, because potassium carbonate and sodium carbonate are relatively soluble in water, and are not substituted with highly fluorine-substituted hydrogen-containing substances and unsaturated perfluorinated substances during the neutralization reaction. The reaction of hydrocarbon substances is beneficial to improve the recovery rate of perfluorocarboxylates.

In step (1), the concentration of the alkali solution is 0.5 ~ 2mol/L, and the alkali solution in this concentration range can ensure the mildness of the reaction conditions. If the concentration of the alkali solution is too high, it will cause the alkali solution to have a high degree of The substituted hydrogen-containing substances react with unsaturated perfluorocarbons to form brown substances, which is not conducive to the recycling of perfluorocarboxylates.

In step (1), the preferred reaction temperature is 5-25°C, the reaction is relatively mild at this temperature, and no gel phenomenon will occur. The optimal reaction time is 5-6 hours to ensure sufficient reaction. The optimal pH value at the end of the reaction is 7~8, if the alkali solution is added in excess, it will increase the difficulty of subsequent treatment.

After the treatment of step (1), the water phase and the oil phase are obtained by separation.

In step (2), the main components of the water phase are perfluorocarboxylates, fluoride salts and excess alkali. Among them, perfluorocarboxylates are dissolved in methanol, while fluoride salts and excess alkali are insoluble in methanol.

The specific steps of step (2) are to evaporate the water phase to dryness to obtain the crude perfluorocarboxylate, then add methanol to dissolve the crude perfluorocarboxylate, filter the solution, and evaporate the methanol solvent to obtain the purified perfluorocarboxylate. salt.

Among them, a rotary evaporator can be used to evaporate water in the water phase. Since perfluorocarboxylate is a good surfactant, bumping is prone to occur in this process, so the suitable temperature for operation is 30~55°C, and the pressure is - 0.1~0MPa.

In order to ensure that the crude perfluorocarboxylate is completely dissolved in methanol, the mass ratio of methanol to crude perfluorocarboxylate is 3:1-10:1.

Through filtration, the methanol-insoluble fluoride salt and excess alkali can be filtered out, and the methanol solvent can be evaporated to obtain a relatively pure perfluorocarboxylate. The purity of the perfluorocarboxylate obtained by the method of measuring fluoride ion in GB7483-87 "Determination of Fluoride in Water Quality by Spectrophotometry of Fluorine Reagent" can be measured to obtain the perfluorocarboxylic acid obtained after step (2) methanol extraction The purity of the salt is over 95%.

In step (3), the main components of the oil phase are inert inert fluorocarbons and trace amounts of toxic substances (highly fluorine-substituted hydrogen-containing substances and unsaturated perfluorocarbons). The obtained oil phase is separated and purified to obtain purified inert fluorocarbons. Pyridine, piperidine reagent color reaction and ultraviolet (detection band 200~320nm) scanning can be used to detect the purification effect.

The separation and purification of the oil phase is carried out by the following three methods:

Method 1: Add ethanol-water-KOH mixed reagent to the oil phase, stir the reaction evenly, separate the organic layer, and then wash the organic layer with water to obtain the purified inert fluorocarbon compound.

In order to further improve the rate of recovery of inert fluorocarbons, the mass ratio of ethanol, water, and KOH in the ethanol-water-KOH mixed reagent is 1:1:1, and the described ethanol-water-KOH mixed reagent is mixed with the oil phase The mass ratio is 1:1~5:1.

Method 2: Add potassium permanganate-alkali-water mixed reagent to the oil phase for reflux reaction, and then collect fractions at 65°C~90°C by conventional atmospheric distillation to obtain purified inert fluorocarbons.

In order to further improve the recovery rate of inert fluorocarbons, the alkali is KOH or NaOH, and the mass fraction of potassium permanganate in the potassium permanganate-alkali-water mixed reagent is 5%~30%, and the alkali and high The mass ratio of potassium manganate is 0.5:1-2:1, and the mass ratio of the potassium permanganate-alkali-water mixed reagent to the oil phase is 1:1-5:1.

Method 3: Add methanol to the oil phase, stir evenly, let stand, separate the lower oil phase, then add methanol to the lower oil phase, and repeat the extraction for 3 to 8 times to obtain purified inert fluorocarbons. Further preferably, the mass ratio of the methanol added each time to the oil phase is 1:1-1:5.

Compared with the prior art, the beneficial technical effect of the present invention is:

(1) The treatment conditions of the present invention are mild, the operating temperature of the process is below 100°C, and all steps can be operated under normal pressure. Compared with the current direct combustion method for treating this perfluoroalkyl fluoride waste, Safety and energy consumption are more superior. The purification methods of the three inert fluorocarbons used are relatively simple to operate. Among them, potassium permanganate-alkali-water reagent, ethanol, water, KOH (1:1:1) reagent is used to effectively remove hydrogen and unsaturated substances in the separated inert fluorocarbon without high pressure. In particular, the methanol extraction method is used and operated at normal temperature. The methanol used can be recycled and reused, which can effectively reduce waste emissions and avoid secondary pollution problems, and is more economical in terms of cost; the same method is used to purify perfluorocarboxylates by methanol extraction Salts can effectively separate perfluorocarboxylates from fluorinated salts, and the purity of the obtained perfluorocarboxylates can reach more than 95%. Only a single solvent is used in the process, and the solvent can be recycled.

(2) The present invention can recover most of the perfluoroalkyl fluoride wastes, and realize the graded utilization of the perfluoroalkyl fluoride wastes, and can obtain high-purity perfluorocarboxylates and inert fluorocarbons respectively. Two kinds of products of compound, perfluorocarboxylate can be used as fluorine surfactant, such as emulsifier, foaming agent, pigment dispersant used in emulsion polymerization, etc., inert fluorocarbon has good stability, can be used as fluorine Oil or inert perfluorinated solvents are used in precision instrument cleaning, as dielectric materials and heat carriers and other fields.

Detailed ways

Below by embodiment the present invention is further elaborated.

Example 1:

This embodiment discloses a method for treating perfluoroalkyl fluoride waste, and the specific steps are as follows:

(1) Introduce 50ml of perfluoroalkyl fluoride waste into a 500ml jacketed reaction kettle, through which condensed water at a temperature of 5°C is passed through the jacket. After the temperature in the reactor and the temperature of the condensed water reach equilibrium , slowly drop about 150ml of the prepared 1mol/L K ₂ CO ₃ solution into the perfluoroalkyl fluoride waste while stirring continuously. A large amount of heat is released during this process, and the temperature in the reactor needs to be kept below 25°C. After the dropwise addition of the alkali solution is completed, the stirring is continued for 5 hours to ensure complete hydrolysis of the perfluoroalkyl acid fluoride and complete acid-base neutralization reaction. Then stop stirring and let it stand for 2h to separate the water phase and the oil phase. Then take out the reaction mixture and pour it into a 250ml separatory funnel, separate out 25ml of the lower oil phase and 170ml of the aqueous phase containing perfluorocarboxylate;

(2) The obtained water phase was evaporated to dryness with a rotary evaporator. The suitable temperature for operation was 30-55° C. and the pressure was -0.1-0 MPa to obtain about 38 g of the crude product of perfluorocarboxylate. Add 200ml of methanol to dissolve the crude perfluorocarboxylate, and then distill off the methanol after filtration to obtain about 15 g of perfluorocarboxylate;

(3) Pour 25ml of the separated oil phase containing inert fluorocarbons into a three-necked flask, connect the condensing reflux tube and a thermometer, heat to 50°C, add ethanol-water-KOH solution (1/1/1) mixed reagent About 10ml. Heat to reflux for 12 hours under stirring conditions (the temperature must not exceed 60°C), cool the mixture, separate the layers to obtain an organic layer, and then wash with water to obtain about 20 ml of purified inert fluorocarbons.

Example 2:

This embodiment discloses a method for treating perfluoroalkyl fluoride waste, and the specific steps are as follows:

(1) Introduce 50ml of perfluoroalkyl fluoride waste into a 500ml jacketed reaction kettle, and pass through the jacket with condensed water at a temperature of 5°C. After the temperature in the reactor and the temperature of the condensed water reach equilibrium , slowly drop about 150ml of the prepared 1mol/L Na ₂ CO ₃ solution into the perfluoroalkyl fluoride waste while stirring continuously. A large amount of heat is released during this process, and the temperature in the reactor needs to be kept below 10°C. At the same time, due to the low solubility of NaF in water (4.06g/100g water (20°C), a large amount of NaF precipitated during the dropping process. After the dropwise addition of the alkali solution is completed, the stirring is continued for 5 hours to ensure complete hydrolysis of the perfluoroalkyl acid fluoride and complete acid-base neutralization reaction. Then the stirring was stopped, and the precipitated NaF was separated by filtration, which weighed about 6 g after drying, and the remaining reaction mixture continued to stand for 2 h, so that the water phase and the oil phase were separated. Then take out the reaction mixture and pour it into a 250ml separatory funnel, separate out 23ml of the lower oil phase, and 161ml of the aqueous phase containing perfluorocarboxylate;

(2) The obtained water phase was evaporated to dryness with a rotary evaporator. The suitable temperature for operation was 30-55° C. and the pressure was -0.1-0 MPa to obtain about 27 g of the crude product of perfluorocarboxylate. Add 200ml of methanol to dissolve the crude perfluorocarboxylate, and then distill off the methanol after filtration to obtain about 14 g of perfluorocarboxylate;

(3) Pour 23ml of the separated oil phase into a three-necked flask, connect the condensing reflux tube and a thermometer, heat to 50°C, add about 8ml of ethanol-water-KOH solution (1/1/1) mixed reagent. After stirring for 12 hours (the temperature should not exceed 60°C), the mixture was cooled, separated to obtain an organic layer, and washed with water to obtain about 18 ml of purified inert fluorocarbons.

Example 3:

This embodiment discloses a method for treating perfluoroalkyl fluoride waste, and the specific steps are as follows:

(1) Introduce 25ml of perfluoroalkyl fluoride waste into a 500ml jacketed reaction kettle, and pass through the jacket with condensed water at a temperature of 5°C. After the temperature in the reactor and the temperature of the condensed water reach equilibrium , Slowly add about 300ml of the prepared 1mol/L KHCO ₃ solution dropwise into the perfluoroalkyl fluoride waste while stirring continuously. A large amount of heat is released during this process, and the temperature in the reactor needs to be kept below 25°C. After the dropwise addition of the alkali solution is completed, the stirring is continued for 5 hours to ensure complete hydrolysis of the perfluoroalkyl acid fluoride and complete acid-base neutralization reaction. Then stop stirring and let it stand for 2h to separate the water phase and the oil phase. Then take out the reaction mixture and pour it into a 500ml separatory funnel, separate the lower oil phase 12ml, and the aqueous phase containing perfluorocarboxylate 310ml;

(2) The obtained water phase was evaporated to dryness with a rotary evaporator. The suitable temperature for operation was 30-55° C. and the pressure was -0.1-0 MPa to obtain about 16 g of the crude product of perfluorocarboxylate. Add 80ml~150ml of methanol to dissolve the crude product of perfluorocarboxylate, filter and then distill off the methanol to obtain about 7g of perfluorocarboxylate;

(3) Pour 12ml of the separated oil phase into a three-necked flask, connect the condensing reflux tube and a thermometer, heat to 50°C, add about 3~8ml of ethanol-water-KOH solution (1/1/1) mixed reagent. After stirring for 12 hours (the temperature should not exceed 60°C), the mixture was cooled, separated to obtain an organic layer, and then washed with water to obtain about 8 ml of purified inert fluorocarbons.

Example 4:

This embodiment discloses a method for treating perfluoroalkyl fluoride waste, and the specific steps are as follows:

(1) Introduce 25ml of perfluoroalkyl fluoride waste into a 500ml plastic reaction kettle with a jacket. Condensed water at a temperature of 5°C is passed through the jacket, and the temperature in the reactor and the temperature of the condensed water reach equilibrium. Finally, about 300ml of the configured 1mol/L NaHCO ₃ solution was slowly added dropwise to the perfluoroalkyl fluoride waste while stirring continuously. A large amount of heat is released during this process, and the temperature in the reactor needs to be kept below 25°C. During the dropwise addition of alkali solution, NaF was partially separated out. After the dropwise addition, continue to stir for 5 hours to ensure complete hydrolysis of perfluoroalkyl acid fluoride and complete acid-base neutralization reaction. Then the stirring was stopped, and the precipitated NaF was separated by filtration, which weighed about 1 g after drying, and the remaining reaction mixture continued to stand for 2 hours to ensure the separation of the water phase and the oil phase. Then take out the reaction mixture and pour it into a 500ml separatory funnel, separate the lower oil phase 12ml, and the aqueous phase containing perfluorocarboxylate 307ml;

(2) The obtained water phase was evaporated to dryness with a rotary evaporator. The suitable temperature for operation was 30-55° C. and the pressure was -0.1-0 MPa to obtain about 14 g of the crude product of perfluorocarboxylate. Add 100ml of methanol to dissolve the crude perfluorocarboxylate, and then distill off the methanol after filtration to obtain about 6.5g of perfluorocarboxylate;

(3) Pour 12ml of the separated oil phase into a three-necked flask, connect the condensing reflux tube and a thermometer, heat to 50°C, add about 3~8ml of ethanol-water-KOH solution (1/1/1) mixed reagent. After stirring for 12 hours (the temperature should not exceed 60°C), the mixture was cooled, separated to obtain an organic layer, and then washed with water to obtain about 8 ml of purified inert fluorocarbons.

Example 5:

The difference between this example and Example 1 is that the concentration of the added _K2CO3 solution is changed to 2mol/L, the added amount is adjusted to _75ml , and other treatment methods are the same as in Example 1 to obtain purified perfluorinated Carboxylate 13g, purified inert fluorocarbon 20ml.

Embodiment 6:

The difference between this example and Example 1 is: the concentration of the added _K2CO3 solution is changed to 0.5mol/L, _the amount added is adjusted to 300ml, other treatment methods are the same as in Example 1, and the purified whole Fluorocarboxylate 12.5g, purified inert fluorocarbon 18ml.

Embodiment 7:

The difference between this example and Example 1 is that the purification treatment method of the separated oil phase solution is changed, put 25ml of the oil phase into a three-necked flask, connect the condensing reflux tube, a thermometer, and heat to 50°C. Add 10 grams of potassium permanganate, 5 grams of sodium hydroxide and 100 milliliters of water under stirring, stir and reflux for 24 hours at 70 ° C, collect fractions at 65 ° C to 90 ° C, and obtain 12 ml of purified inert fluorocarbons.

Embodiment 8:

The difference between this example and Example 1 is that the purification treatment method of the separated oil phase solution is changed to extraction with methanol, that is, 5 ml of methanol is added to the separated 25 ml of oil phase. Stir for 30 minutes, let stand for 30 minutes, pour the mixture into a separatory funnel, and separate the lower oil phase. Then add 5ml methanol to the oil phase, repeat the above operation 5 times. 16 ml of purified inert fluorocarbons were obtained.

Claims (4)

1. a treatment process for perfluoroalkyl acyl fluoride waste, is characterized in that, comprises the following steps:

(1) in perfluoroalkyl acyl fluoride waste, add alkaline solution to react, adjust ph to 7 ~ 8, leave standstill, be separated and obtain aqueous phase and oil phase; Described alkaline solution is at least one in potassium hydroxide solution, sodium hydroxide solution, solution of potassium carbonate, sodium carbonate solution, sodium hydrogen carbonate solution and potassium bicarbonate solution;

(2) from aqueous phase, separation and purification obtains perfluorocarboxylic acid salt; Described purification procedures is: after aqueous phase evaporating water, obtains perfluorocarboxylic acid salt crude product, then adds dissolve with methanol perfluorocarboxylic acid salt crude product, filtering solution, evaporative removal methanol solvate, obtains the perfluorocarboxylic acid salt after purifying;

(3) from oil phase, separation and purification obtains inertia fluorocarbon; Described purification procedures is: add methyl alcohol in oil phase, after stirring, leaves standstill, isolates lower floor's oil phase, then add methyl alcohol in lower floor's oil phase, repeatedly extract 3 ~ 8 times, obtain the inertia fluorocarbon after purifying.

2. the treatment process of perfluoroalkyl acyl fluoride waste as claimed in claim 1, it is characterized in that: in step (1), described alkaline solution is solution of potassium carbonate or sodium carbonate solution.

3. the treatment process of perfluoroalkyl acyl fluoride waste as claimed in claim 1, it is characterized in that: in step (1), described alkaline concentration is 0.5 ~ 2mol/L.

4. the treatment process of perfluoroalkyl acyl fluoride waste as claimed in claim 1, it is characterized in that: in step (1), temperature of reaction is 5 ~ 25 DEG C, and the reaction times is 5 ~ 6h.