Method for purifying tail gas of copper-clad plate

Abstract

The invention provides a purification method of copper-clad plate tail gas, and belongs to the technical field of waste gas treatment. The purification method of the copper-clad plate tail gas comprises the following steps: carrying out reverse contact on the copper-clad plate tail gas and an organic solvent to obtain the organic solvent containing the copper-clad plate tail gas; and rectifying the organic solvent containing the copper-clad plate tail gas to obtain ketones, the organic solvent and propylene glycol monomethyl ether and / or N, N-dimethylformamide. Organic components (acetone and / or butanone, propylene glycol monomethyl ether and / or N, N-dimethylformamide) in the copper-clad plate tail gas can be absorbed by adopting the organic solvent, then rectification is carried out, the organic components are recovered, separated and purified, the components are separated by utilizing different volatilities of the components in the mixture, and the recovery rate of the copper-clad plate tail gas is improved. Therefore, ketones, the organic solvent and propylene glycol monomethyl ether and / or N, N-dimethylformamide are obtained, and the purpose of separation and purification is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of waste gas treatment, and in particular relates to a method for purifying tail gas of a copper clad laminate. Background Art

[0002] A large amount of organic tail gas (main components: acetone and / or butanone, propylene glycol methyl ether and / or N,N-dimethylformamide) is generated during the drying process of copper clad laminates. At present, the tail gas is mainly treated by incineration, and the heat from the incineration is used to heat the thermal oil and then reused for oven heating; this method cannot achieve the recovery of the organic components of the tail gas, resulting in a waste of resources. Therefore, how to achieve the recovery of organic components in the tail gas of copper clad laminates has become a technical problem that needs to be solved urgently in this field. Summary of the invention

[0003] The object of the present invention is to provide a method for purifying tail gas of copper clad laminates. The method for purifying tail gas of copper clad laminates provided by the present invention can realize the recovery and purification of organic components with high purity.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] The present invention provides a method for purifying tail gas of a copper-clad laminate, comprising the following steps:

[0006] (1) contacting the copper-clad laminate tail gas with an organic solvent in reverse order to obtain an organic solvent containing the copper-clad laminate tail gas;

[0007] (2) distilling the organic solvent containing the copper-clad laminate tail gas obtained in step (1) to remove ketones, organic solvents, propylene glycol methyl ether and / or N,N-dimethylformamide.

[0008] Preferably, the organic solvent in step (1) comprises at least one of ethylene glycol diacetate, N-methylpyrrolidone and dimethyl sulfoxide.

[0009] Preferably, the distillation in step (2) is carried out in a distillation tower; the bottom temperature of the distillation tower is 160-190° C., the reflux ratio of the distillation tower is 0.2-1, and the theoretical plate number of the distillation tower is 20-30.

[0010] Preferably, the bottom temperature of the distillation tower is 165-185° C., the reflux ratio of the distillation tower is 0.4-0.8, and the theoretical plate number of the distillation tower is 22-28.

[0011] Preferably, when the ketone obtained by distillation in step (2) is acetone, the top temperature of the distillation tower used for distillation is 55-60°C.

[0012] Preferably, when the ketone obtained by distillation in step (2) is butanone, the top temperature of the distillation tower used for distillation is 79-82°C.

[0013] Preferably, when propylene glycol methyl ether is obtained by distillation in step (2), the top temperature of the distillation tower used for distillation is 115-125°C.

[0014] Preferably, when N,N-dimethylformamide is obtained by distillation in step (2), the top temperature of the distillation tower used for distillation is 150-160°C.

[0015] Preferably, the organic solvent containing copper-clad laminate tail gas in step (2) also includes preheating before distillation.

[0016] Preferably, the preheating temperature is 40-50°C.

[0017] The present invention provides a method for purifying tail gas of copper clad laminates, comprising the following steps: contacting the tail gas of copper clad laminates with an organic solvent in reverse order to obtain an organic solvent containing the tail gas of copper clad laminates; and rectifying the organic solvent containing the tail gas of copper clad laminates to obtain ketones, an organic solvent, and propylene glycol methyl ether and / or N,N-dimethylformamide. The present invention uses an organic solvent to absorb organic components (acetone and / or butanone, propylene glycol methyl ether and / or N,N-dimethylformamide) in the tail gas of copper clad laminates, and then rectifying to recover, separate and purify the organic components, and separate the components by utilizing the different volatilities of the components in the mixture, thereby obtaining ketones, an organic solvent, and propylene glycol methyl ether and / or N,N-dimethylformamide, thereby achieving the purpose of separation and purification. Experimental results show that the purity of acetone obtained by the copper-clad laminate tail gas purification method provided by the present invention is greater than 99.5%, the purity of butanone is greater than 99.5%, the purity of propylene glycol methyl ether is greater than 99.5%, and the purity of N,N-dimethylformamide is greater than 99.5%. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The schematic diagram of the distillation of the organic solvent containing copper clad laminate tail gas according to the present invention. DETAILED DESCRIPTION

[0019] The present invention provides a method for purifying tail gas of a copper-clad laminate, comprising the following steps:

[0020] (1) contacting the copper-clad laminate tail gas with an organic solvent in reverse order to obtain an organic solvent containing the copper-clad laminate tail gas;

[0021] (2) distilling the organic solvent containing the copper-clad laminate tail gas obtained in step (1) to obtain ketones, organic solvents, propylene glycol methyl ether and / or N,N-dimethylformamide.

[0022] The present invention has no particular limitation on the sources of the raw materials, and commercially available products known to those skilled in the art may be used.

[0023] The purification method provided by the present invention is applicable to tail gas of copper-clad laminates, and is preferably applicable to tail gas of copper-clad laminates containing acetone and / or butanone and propylene glycol methyl ether and / or N,N-dimethylformamide.

[0024] The present invention has no particular limitation on the contents of the acetone, butanone, propylene glycol methyl ether and N,N-dimethylformamide, and any contents are acceptable.

[0025] The invention makes the tail gas of the copper clad laminate contact with the organic solvent in reverse order to obtain the organic solvent containing the tail gas of the copper clad laminate. The invention uses the organic solvent to absorb the organic components (acetone and / or butanone, propylene glycol methyl ether and / or N,N-dimethylformamide) in the tail gas of the copper clad laminate.

[0026] In the present invention, the organic solvent preferably includes at least one of ethylene glycol diacetate, N-methylpyrrolidone and dimethyl sulfoxide, and more preferably N-methylpyrrolidone (NMP). The present invention has no particular limitation on the amount of the organic solvent, as long as the organic components in the tail gas of the copper clad laminate are completely absorbed.

[0027] In the present invention, the reverse contact is preferably carried out in a spray tower. The present invention has no particular limitation on the type of the spray tower, and any equipment well known to those skilled in the art can be used.

[0028] The present invention has no special limitation on the operation of the reverse contact, as long as the organic components in the tail gas of the copper-clad laminate are completely absorbed.

[0029] In the present invention, the waste gas obtained by the reverse contact is preferably discharged into the air after being washed with water. The present invention has no special limitation on the operation of the discharge into the air, and the operation well known to those skilled in the art can be adopted.

[0030] The present invention has no particular limitation on the water washing operation, which can be determined according to common sense.

[0031] After obtaining the organic solvent containing the tail gas of the copper-clad laminate, the present invention performs rectification on the organic solvent containing the tail gas of the copper-clad laminate to obtain ketones, organic solvents, propylene glycol methyl ether and / or N,N-dimethylformamide. The present invention adopts rectification to recover, separate and purify the organic components, and separates the components in the mixture by utilizing the different volatilities of the components, thereby obtaining ketones, organic solvents, propylene glycol methyl ether and / or N,N-dimethylformamide, and achieving the purpose of separation and purification.

[0032] In the present invention, the organic solvent containing copper-clad laminate tail gas is further preheated before distillation; the preheating temperature is preferably 40-50°C. As an embodiment, the preheating temperature can be 42-48°C, or 44-46°C. The present invention preheats the organic solvent containing copper-clad laminate tail gas to keep the temperature of the raw materials entering the distillation tower constant, increase the reaction rate, save energy consumption, and improve the separation effect in the distillation process.

[0033] The present invention has no limitation on the preheating time, which can be adjusted according to actual needs.

[0034] In the present invention, the distillation is preferably carried out in a distillation tower; the distillation tower is preferably a batch distillation tower. The present invention has no special limitation on the model of the distillation tower, and any equipment well known to those skilled in the art can be used.

[0035] In the present invention, the distillation preferably produces acetone and / or butanone and propylene glycol methyl ether and / or N,N-dimethylformamide in gas phase in sequence from the top of the tower; and the distillation preferably produces the organic solvent from the bottom of the tower.

[0036] In the present invention, the bottom temperature of the distillation tower is preferably 160-190°C; the reflux ratio of the distillation tower is preferably 0.2-1; and the theoretical plate number of the distillation tower is preferably 20-30. As an embodiment, the bottom temperature of the distillation tower can be 162-185°C, or 165-175°C; the reflux ratio of the distillation tower can be 0.4-0.8, or 0.5, 0.6 or 0.7; and the theoretical plate number of the distillation tower can be 22-28, or 23, 24, 25, 26 or 27. The present invention limits the bottom temperature, reflux ratio and theoretical plate number of the distillation tower within the above ranges to further improve the distillation effect, thereby further improving the purity of each component.

[0037] In the present invention, when the ketone obtained by the distillation is acetone, the top temperature of the distillation tower used for the distillation is preferably 55-60° C. As an embodiment, the top temperature of the tower can be 56° C., 57° C., 58° C. or 59° C.

[0038] In the present invention, when the ketone obtained by distillation is butanone, the top temperature of the distillation tower used for distillation is preferably 79-82° C. As an embodiment, the top temperature of the tower can be 80° C. or 81° C.

[0039] In the present invention, when the distillation obtains propylene glycol methyl ether, the top temperature of the distillation tower used for the distillation is preferably 115-125° C. As an embodiment, the top temperature of the tower can be 116° C., 117° C., 118° C., 119° C., 120° C., 121° C., 122, 123, 124 or 124° C.

[0040] In the present invention, when the distillation obtains N,N-dimethylformamide, the top temperature of the distillation tower used for the distillation is preferably 150-160° C. As an embodiment, the top temperature of the tower can be 151° C., 152° C., 153° C., 154° C., 155° C., 156° C., 157° C., 158° C. or 159° C.

[0041] In the present invention, the distillation pressure is preferably normal pressure.

[0042] In the present invention, when the organic solvent containing the copper-clad laminate tail gas includes acetone, butanone and propylene glycol methyl ether, the tower top temperature during the distillation is preferably first set to 55-60°C to produce acetone, then the tower top temperature is raised to 79-82°C to produce butanone, and then the tower top temperature is raised to 115-125°C to produce propylene glycol methyl ether.

[0043] In the present invention, when the organic solvent containing the copper-clad laminate tail gas includes acetone, butanone and N,N-dimethylformamide, the tower top temperature during the distillation is preferably first set to 55-60°C to produce acetone, then the tower top temperature is raised to 79-82°C to produce butanone, and then the tower top temperature is raised to 150-160°C to produce N,N-dimethylformamide.

[0044] In the present invention, when the organic solvent containing the copper-clad laminate tail gas includes butanone, propylene glycol methyl ether and N,N-dimethylformamide, the tower top temperature during the distillation is preferably first set to 79-82°C to produce butanone, then the tower top temperature is raised to 115-125°C to produce propylene glycol methyl ether, and then the tower top temperature is raised to 150-160°C to produce N,N-dimethylformamide.

[0045] The present invention has no particular limitation on the heating rate, and operations familiar to those skilled in the art may be adopted.

[0046] The acetone and / or butanone and propylene glycol methyl ether and / or N,N-dimethylformamide obtained by the purification method provided by the present invention can meet the process recycling requirements of the solvent.

[0047] The present invention adopts distillation to recover, separate and purify organic components. By utilizing the characteristics that each component in the mixture has different vapor pressures (i.e., different volatilities) at a certain temperature, the liquid mixture is heated, partially vaporized and partially condensed for multiple times, and gas-liquid mass transfer and heat transfer are performed in a distillation tower, so that the content of the component with low volatility in the gas phase is significantly higher than that in the liquid phase, thereby achieving the purpose of separating and purifying the component from the mixed liquid.

[0048] Figure 1 The schematic diagram of the distillation of the organic solvent containing copper clad laminate tail gas according to the present invention.

[0049] from Figure 1It can be seen that the organic solvent containing copper-clad laminate tail gas is distilled, acetone, butanone and propylene glycol methyl ether / N,N-dimethylformamide are produced from the top of the tower, and organic solvents such as NMP are produced from the bottom of the tower.

[0050] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] Example 1

[0052] The purification method of copper clad laminate tail gas is as follows:

[0053] (1) The tail gas of the copper clad laminate is contacted with NMP in a spray tower in reverse order to obtain an organic solvent containing the tail gas of the copper clad laminate. The tail gas obtained by the reverse contact is washed with water and then discharged to the air; wherein the acetone content of the tail gas of the copper clad laminate is 17.1 g / m 3 , butanone is 17.3g / m 3 , propylene glycol methyl ether is 8.4g / m 3 ;

[0054] (2) preheating the organic solvent containing the copper-clad plate tail gas obtained in the step (1) to 48° C., and then entering an intermittent distillation tower for distillation at normal pressure, first extracting acetone in the gas phase when the tower top temperature is 57° C., then heating the tower top to 79° C. to extract butanone in the gas phase, and then heating the tower top to 120° C. to extract propylene glycol methyl ether in the gas phase, and extracting NMP in the tower bottom; wherein the tower bottom temperature is 162° C., the reflux ratio is 0.6, and the theoretical plate number is 20.

[0055] The acetone, butanone and propylene glycol methyl ether obtained by the purification method of Example 1 were tested, and the purity was: 99.9% for acetone, 99.7% for butanone, and 99.7% for propylene glycol methyl ether; the yield was 88% for acetone, 90% for butanone, and 90% for propylene glycol methyl ether.

[0056] Example 2

[0057] The purification method of copper clad laminate tail gas is as follows:

[0058] (1) The tail gas of the copper clad laminate is contacted with NMP in reverse in a spray tower to obtain an organic solvent containing the tail gas of the copper clad laminate, and the tail gas obtained by the reverse contact is washed with water and then discharged to the air; wherein the acetone content of the tail gas of the copper clad laminate is 14 g / m 3 , butanone is 20.5g / m 3 , N,N-dimethylformamide is 11.5g / m 3 ;

[0059] (2) preheating the organic solvent containing the copper-clad plate tail gas obtained in the step (1) to 48° C., and then entering an intermittent distillation tower for distillation at normal pressure, first extracting acetone in the gas phase when the tower top temperature is 57° C., then heating the tower top to 79° C. to extract butanone in the gas phase, and then heating the tower top to 155° C. to extract N,N-dimethylformamide in the gas phase, and extracting NMP in the tower bottom; wherein the tower bottom temperature is 165° C., the reflux ratio is 0.6, and the theoretical plate number is 23.

[0060] The acetone, butanone and N,N-dimethylformamide obtained by the purification method of Example 2 were tested for purity, and the purity was: 99.9% for acetone, 99.7% for butanone, and 99.7% for N,N-dimethylformamide; the yields were: 88% for acetone, 90% for butanone, and 90% for N,N-dimethylformamide.

[0061] Example 3

[0062] The purification method of copper clad laminate tail gas is as follows:

[0063] (1) The tail gas of the copper clad laminate is contacted with NMP in reverse in a spray tower to obtain an organic solvent containing the tail gas of the copper clad laminate, and the tail gas obtained by the reverse contact is discharged to the air; wherein the butanone in the tail gas of the copper clad laminate is 35g / m 3 , propylene glycol methyl ether is 17.2g / m 3 , N,N-dimethylformamide is 20.1g / m 3 ;

[0064] (2) preheating the organic solvent containing the copper-clad plate tail gas obtained in the step (1) to 48° C., and then entering an intermittent distillation tower for distillation under normal pressure, first extracting butanone in the gas phase at a tower top temperature of 79° C., then heating the temperature to 120° C. to extract propylene glycol methyl ether, and then heating the temperature to 155° C. to extract N,N-dimethylformamide in the gas phase, and extracting NMP in the tower bottom, wherein the tower bottom temperature is 165° C., the reflux ratio is 0.5, and the number of theoretical plates is 23.

[0065] The butanone, propylene glycol methyl ether and N,N-dimethylformamide obtained by the purification method of Example 3 were tested for purity. The purity was: butanone 99.7%, propylene glycol methyl ether 99.8%, N,N-dimethylformamide 99.8%; the yield was: butanone 87%, propylene glycol methyl ether 90%, N,N-dimethylformamide 90%.

[0066] It can be seen from the above embodiments that the method for purifying tail gas from copper-clad laminates provided by the present invention can realize the recovery and purification of organic components with high purity.

[0067] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for purifying tail gas from a copper-clad laminate, comprising the following steps: (1) contacting the copper-clad laminate tail gas with an organic solvent in reverse order to obtain an organic solvent containing the copper-clad laminate tail gas; (2) distilling the organic solvent containing the copper-clad laminate tail gas obtained in step (1) to obtain ketones, organic solvents, propylene glycol methyl ether and / or N,N-dimethylformamide.

2. The purification method according to claim 1, characterized in that The organic solvent in step (1) includes at least one of ethylene glycol diacetate, N-methylpyrrolidone and dimethyl sulfoxide.

3. The purification method according to claim 1, characterized in that The distillation in step (2) is carried out in a distillation tower; the bottom temperature of the distillation tower is 160-190° C., the reflux ratio of the distillation tower is 0.2-1, and the theoretical plate number of the distillation tower is 20-30.

4. The purification method according to claim 3, characterized in that The bottom temperature of the distillation tower is 165-185° C., the reflux ratio of the distillation tower is 0.4-0.8, and the theoretical plate number of the distillation tower is 22-28.

5. The purification method according to claim 1, characterized in that: When the ketone obtained by distillation in step (2) is acetone, the top temperature of the distillation tower used for distillation is 55-60°C.

6. The purification method according to claim 1, characterized in that: When the ketone obtained by distillation in step (2) is butanone, the top temperature of the distillation tower used for distillation is 79-82°C.

7. The purification method according to claim 1, characterized in that: When propylene glycol methyl ether is obtained by distillation in step (2), the top temperature of the distillation tower used for distillation is 115-125°C.

8. The purification method according to claim 1, characterized in that: When N,N-dimethylformamide is obtained by distillation in step (2), the top temperature of the distillation tower used for distillation is 150-160°C.

9. The purification method according to claim 1, characterized in that: The organic solvent containing copper-clad laminate tail gas in step (2) also includes preheating before distillation.

10. The purification method according to claim 9, characterized in that: The preheating temperature is 40-50°C.

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