Additive for photoresist waste liquid resource recovery and photoresist waste liquid recovery method

Abstract

The invention relates to an additive for photoresist waste liquid resource recovery and a photoresist waste liquid recovery method, and belongs to the technical field of photoresist waste liquid treatment.The additive is prepared from, by mass, 10%-20% of water, 5%-10% of alkali liquor and 70%-85% of N-methyl pyrrolidone, the total mass of the water, the alkali liquor and the N-methyl pyrrolidone is 100%, and the total mass of the water, the alkali liquor and the N-methyl pyrrolidone is 100%. The photoresist waste liquid contains acetone, butanone, ethylene glycol monomethyl ether, water and epoxy resin, the addition amount of the additive is 0.5-2% of the content of the photoresist waste liquid, and the mass ratio of the water in the additive to the epoxy resin in the photoresist waste liquid is lt; 3: 1. According to the present invention, with the application of the additive to recover the acetone and the butanone in the photoresist waste liquid, the recovery rate of the acetone and the butanone is high, the viscosity of the epoxy resin hanging wall in the photoresist waste liquid can be fundamentally changed, and the trouble of secondary cleaning is avoided.

Description

Technical Field

[0001] This application relates to the field of photoresist waste liquid treatment technology, and in particular to an additive for recycling photoresist waste liquid and a method for recycling photoresist waste liquid, especially an additive for recycling photoresist waste liquid containing acetone and methyl ethyl ketone and a method for recycling photoresist waste liquid. Background Technology

[0002] Photoresist remover solutions in the electronics industry are primarily used to remove photoresist from semiconductor chips. The waste liquid after use contains acetone, methyl ethyl ketone (MEK), water, and photoresist. Direct discharge of this waste liquid not only causes environmental pollution but also wastes valuable organic solvents. Currently, the main challenge in the resource recovery of this waste liquid lies in photoresist removal. Photoresist accounts for 2-10% of the waste liquid; it easily solidifies upon contact with water, and when mixed with acetone and MEK of varying moisture content, it readily forms a film on the inner wall of the reactor, affecting heat exchange efficiency and increasing energy consumption and equipment maintenance costs. Existing technologies include Chinese patent CN114380436B, which uses plasma discharge for photoresist removal, but this method is costly, has numerous side reactions, is highly dangerous, and involves cumbersome procedures. Chinese patent CN116693102A uses mechanical equipment to stress-scrape away the adhesive, but excessive adhesive can lead to a gradual increase in motor power, damaging the equipment. Furthermore, this solution relies on acetone for scraping, and acetone, being a Class A substance, carries high operational risks and is not practical. Existing technologies generally suffer from high costs, high operational risks, and easy equipment damage, making it difficult to meet the demand for efficient, safe, and low-cost treatment of electronic adhesive removal waste liquid. Summary of the Invention

[0003] The purpose of this application is to address the shortcomings of existing technologies, such as low recovery rate, complex process, and high cost of photoresist waste liquid, and to propose an additive and method for recovering photoresist waste liquid. The additive described in this application combines water, alkaline solution, and N-methylpyrrolidone. A certain amount of water can age and dissolve the resin components in the photoresist waste liquid, causing the resin components to age into fine particles that are easy to remove through subsequent filtration. A certain amount of alkaline solution acts as a lubricant, preventing the resin in the photoresist waste liquid from adhering to the walls and affecting the subsequent flocculation and sedimentation of the resin components. A certain amount of N-methylpyrrolidone can prevent the resin components from rapidly aging and agglomerating after the precipitation of acetone and methyl ethyl ketone in the photoresist waste liquid, which would affect the heat transfer efficiency of the reactor. The synergistic effect of water, alkaline solution, and N-methylpyrrolidone is used as an additive to recover acetone and methyl ethyl ketone from the photoresist waste liquid, resulting in a high recovery rate of acetone and methyl ethyl ketone, a simple recovery process, and low recovery cost.

[0004] In a first aspect, the additive for recycling photoresist waste liquid provided in this application adopts the following technical solution: Based on the total mass of the raw material components of the additive being 100%, the raw material components of the additive include: 10-20% water, 5-10% alkaline solution, and 70-85% N-methylpyrrolidone. The photoresist waste liquid contains acetone, butanone, ethylene glycol methyl ether, water, and epoxy resin. The amount of the additive added is 0.5-2% of the content of the photoresist waste liquid, specifically, for example, 0.5%, 0.8%, 1%, 1.2%, 1.4%, 1.5%, 1.6%, 1.8%, or 2%, preferably 1.2-1.8%. The mass ratio of water in the additive to the mass of epoxy resin in the photoresist waste liquid is <3:1, specifically, for example, 0.44:1, 1:1, 1.67:1, 2:1, or 2.5:1.

[0005] Through the above technical solution, the water in the additive can age and dissolve the resin components in the photoresist waste liquid. When the water content in the additive is within an appropriate range, it can age the epoxy resin in the photoresist waste liquid into fine particles, making it easy to filter. When the mass ratio of water in the additive to the mass of epoxy resin in the photoresist waste liquid is ≥3:1, it easily leads to increased viscosity and agglomeration of the epoxy resin. Adjusting the pH value to 7-9 with a certain amount of alkaline solution can act as a lubricant, preventing the resin in the photoresist waste liquid from adhering to the walls and thus affecting the subsequent flocculation and sedimentation of the resin components. Adding N to the photoresist waste liquid... N-methylpyrrolidone ensures that acetone and butanone are effectively distilled off as fractions during the distillation process, resulting in high recovery rates for acetone and butanone. Simultaneously, N-methylpyrrolidone remains in the residual photoresist waste liquid, preventing it from adhering to the walls and facilitating easy sedimentation and discharge. When the amount of the additive is less than 0.5% of the photoresist waste liquid content, the photoresist removal is incomplete, leading to film formation, hardening, and adhesion on the inner wall of the reactor, resulting in decreased heat exchange efficiency. When the amount of the additive exceeds 2% of the photoresist waste liquid content, steam energy consumption increases, disposal costs rise, and unnecessary production labor is generated.

[0006] Optionally, based on the total mass of the photoresist waste liquid as 100%, the acetone content is 10-90%, specifically, for example, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90%, preferably 40-90%; the butanone content is 0.5-55%, specifically, for example, 0.5%, 5%, 15%, 20%, 25%, 35%, 45%, 50%, or 55%, preferably 20-50%; the ethylene glycol methyl ether content is 0.1-5%, specifically, for example, 10-90%, specifically ... The content of the epoxy resin is 0.1%, 0.5%, 1%, 2%, 3%, 4%, or 5%, preferably 0.5-2%; the water content is 0.1-80%, specifically, for example, 0.1%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, or 80%, preferably 0.1-10%; the epoxy resin content is 0.5-50%, specifically, for example, 0.5%, 5%, 15%, 25%, 35%, 45%, or 50%, preferably 0.5-25%, wherein the epoxy resin is polyepoxychloropropane.

[0007] By using the above technical solution, adding the additives described in this application to photoresist waste liquid containing specific amounts of acetone, methyl ethyl ketone, ethylene glycol methyl ether, water, and epoxy resin can effectively remove epoxy resin from the waste liquid and improve the recovery rate of acetone and methyl ethyl ketone.

[0008] Further optionally, the polyepoxychloropropane has a weight-average molecular weight of 500,000 to 700,000.

[0009] Further optionally, based on the total mass of the photoresist waste liquid as 100%, when the content of acetone is 30-50%, the content of butanone is 10-25%, the content of ethylene glycol methyl ether is 1-5%, the content of water is 5-20%, and the content of epoxy resin is >30%, the raw materials of the additive also include polyaluminum chloride. Based on the total mass of the raw material components of the additive as 100%, the raw material components include: 10-15% water, 5-10% alkali solution, 75-84% N-methylpyrrolidone, and 0.01% polyaluminum chloride.

[0010] Through the above technical solution, when the contents of acetone, methyl ethyl ketone, ethylene glycol methyl ether, water and epoxy resin in the photoresist waste liquid are within a certain range, especially when the epoxy resin content is >30%, the photoresist waste liquid can be treated by using additives containing specific amounts of water, alkaline solution, N-methylpyrrolidone and polyaluminum chloride. This can increase the precipitation efficiency of epoxy resin, reduce the reaction precipitation time, thereby improving the epoxy resin removal rate and further improving the recovery rate of acetone and methyl ethyl ketone.

[0011] Optionally, the polyaluminum chloride is modified polyaluminum chloride, and the raw materials of the modified polyaluminum chloride include polyaluminum chloride (PAC) and carboxymethyl starch (CMS) in a mass ratio of 8 to 12:1. Specifically, for example, the mass ratio of polyaluminum chloride to carboxymethyl starch can be 8:1, 10:1 or 12:1, preferably 10:1. The content of Al2O3 in the polyaluminum chloride is 12 to 28%, specifically, for example, 12%, 15%, 18%, 20%, 22%, 26% or 28%.

[0012] Through the above technical solution, carboxymethyl starch possesses biodegradability and a multi-hydroxyl structure. It forms a hydrogen-bonded network with polyaluminum chloride (PAC), enhancing the flocculation function of PAC, and at a lower cost. When the mass ratio of PAC to carboxymethyl starch is less than 8:1, the carboxyl groups of excess carboxymethyl starch encapsulate the active component of PAC, reducing its positive charge density and weakening its ability to neutralize colloids. Simultaneously, the hydrophilic network of carboxymethyl starch over-expands, encapsulating more acetone / butanone molecules, thus reducing the recovery rate of acetone and butanone. When the mass ratio of PAC to carboxymethyl starch is greater than 12:1, there is an excess of PAC, and free Al... 3+ It readily forms hydrogen bonds with acetone and / or butanone, leading to a decrease in the recovery rate of acetone and butanone.

[0013] Alternatively, the preparation method of the modified polyaluminum chloride includes the following steps: (1) Adjust the pH of the polyaluminum chloride aqueous solution to 3.5~4.0, heat it to 50~70 ℃, keep the stirring speed at 200~300 r / min, and perform aging treatment for 1~2 h to obtain pretreated polyaluminum chloride solution; (2) Dissolve carboxymethyl starch in water and add the pretreated polyaluminum chloride solution to mix. Stir the mixture at 50-70 °C and pH 5.0-6.0 for 1-3 h to obtain the reaction solution. (3) The reaction solution is allowed to stand at 40~50 ℃ for 18~24 h, and then spray-dried at an inlet temperature of 160~200 ℃ and an outlet temperature of 70~90 ℃ to obtain modified polyaluminum chloride.

[0014] Through the above technical solution, in step (1), the pH value of the polyaluminum chloride aqueous solution is adjusted to a specific range, and the temperature is raised for aging treatment. The purpose is to optimize the molecular configuration and activity of PAC and ensure its efficient complexation with CMS. The purpose of step (2) is to achieve molecular-level complexation of PAC and CMS by precisely controlling the reaction conditions, forming a stable and efficient three-dimensional network structure, realizing the synergistic effect of charge neutralization and adsorption bridging, and laying the molecular basis for subsequent efficient flocculation.

[0015] Alternatively, the amount of the additive added is 0.02 to 0.04% of the content of the photoresist waste liquid.

[0016] Through the above technical solution, when the epoxy resin content in the photoresist waste liquid is >30%, the photoresist waste liquid is treated with an additive containing a specific amount of water, alkali solution, N-methylpyrrolidone, and modified polyaluminum chloride prepared by a specific method. The amount of the additive is limited to 0.8~1.2% of the photoresist waste liquid content, which can further improve the recovery rate of acetone and methyl ethyl ketone. At the same time, the epoxy resin removal rate is high and the phenomenon of curing and adhering to the wall is not easy to occur.

[0017] Secondly, this application provides a method for recycling photoresist waste liquid, the recycling method comprising the following steps: S1. The photoresist waste liquid mentioned above is introduced into the reactor, and water containing the additives mentioned above is added to the reactor and stirred to obtain the first mixed system. S2. Add the alkaline solution of the additives mentioned above and N-methylpyrrolidone to the first mixing system to obtain the second mixing system. Let the second mixing system stand and settle, and then filter the settled system. S3. Distill the filtrate obtained in step S2 to obtain acetone and butanone products respectively.

[0018] Through the above technical solution, during the use of the additive, water should be added first and then alkali solution, so that the epoxy resin in the photoresist waste liquid can be effectively settled into powder. The powdered epoxy resin is easy to separate from acetone and methyl ethyl ketone in the waste liquid, thereby improving the recovery rate of acetone and methyl ethyl ketone. If alkali is added first, it is easy to cause the local alkali concentration to be too high, which will cause acetone to denature and affect the recovery rate.

[0019] Optionally, when the epoxy resin content in the photoresist waste liquid is >30%, the polyaluminum chloride mentioned above is added to the settled system before filtering it.

[0020] By using the above technical solution, polyaluminum chloride as a flocculant can age epoxy resin and produce fine precipitates. At the same time, the large number of fine aged resin particles produced can settle quickly, thereby improving the precipitation efficiency of epoxy resin in waste liquid and reducing reaction and precipitation time.

[0021] Optionally, in step S2, the pH value of the second mixture is 7 to 9.

[0022] The above technical solution adjusts the pH value to 7-9 to achieve a lubricating effect and prevents the epoxy resin in the waste liquid from curing and adhering to the wall.

[0023] In summary, this application includes at least one of the following beneficial technical effects: 1. The additive described in this application is effective for specific photoresist waste liquids containing acetone and methyl ethyl ketone across a wide pH range, and is low in cost, relatively controllable, and requires only a small amount to be added. Secondly, it can fundamentally change the viscosity of epoxy resin (adhesive) adhering to the wall in the photoresist waste liquid, eliminating the trouble of secondary cleaning. In addition, acetone and methyl ethyl ketone can be effectively separated from the waste liquid after desizing through the azeotropic principle, and the recovery rate of acetone and methyl ethyl ketone is relatively high. 2. In the process of using the additive described in this application, water should be added first and then alkali solution, so that the epoxy resin in the photoresist waste liquid can be effectively settled into powder. The powdered epoxy resin is easy to separate from acetone and methyl ethyl ketone in the waste liquid, thereby improving the recovery rate of acetone and methyl ethyl ketone. 3. In preferred cases, using polyaluminum chloride modified with carboxymethyl starch can further improve the flocculation and sedimentation of epoxy resin in waste liquid, increase the removal rate of epoxy resin in waste liquid, thereby further improving the recovery rate of acetone and methyl ethyl ketone. Moreover, carboxymethyl starch is biodegradable and will not cause secondary pollution. Attached Figure Description

[0024] Figure 1 The image shows the effect of treating the waste liquid in Example 1. Figure 2 An electronic photograph of the untreated photoresist waste liquid-2; Figure 3 The image shows the effect of treating the waste liquid using Comparative Example 1. Detailed Implementation

[0025] The following combination Figures 1-3 The present application will be further described in detail with reference to specific embodiments.

[0026] The following examples further illustrate the additive for recycling photoresist waste liquid and the method for recycling photoresist waste liquid described in this application. The examples are implemented based on the technical solution of this application, providing detailed implementation methods and specific operating procedures; however, the scope of protection of this application is not limited to the following examples.

[0027] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods in the art. Unless otherwise specified, the experimental materials used in the following embodiments are commercially available.

[0028] Photoresist waste liquid-1: The specific composition is: 50% acetone, 10% butanone, 1% ethylene glycol methyl ether, 5% water, and 34% polyepoxychloropropane (weight average molecular weight is 700,000). Photoresist waste liquid-2: The specific composition is: 38% acetone, 25% butanone, 5% ethylene glycol methyl ether, 20% water, and 12% polyepoxychloropropane (weight average molecular weight is 500,000). Polyaluminum chloride-1: Purchased from Gongyi Haibang Water Purification Materials Co., Ltd., with an Al2O3 content of 28%; Polyaluminum chloride-2: Purchased from Gongyi Haibang Water Purification Materials Co., Ltd., with an Al2O3 content of 12%; Polyaluminum chloride-3: Purchased from Gongyi Haibang Water Purification Materials Co., Ltd., with an Al2O3 content of 30%; Polyaluminum chloride-4: Purchased from Gongyi Haibang Water Purification Materials Co., Ltd., with an Al2O3 content of 10%; Carboxymethyl starch: Purchased from Shanghai Aladdin Technology Co., Ltd., product number C105665.

[0029] Preparation Example 1 Preparation of modified polyaluminum chloride: (1) Dissolve 4 g of polyaluminum chloride-1 in 30 g of water to obtain a polyaluminum chloride aqueous solution. Adjust the pH value of the polyaluminum chloride aqueous solution to 3.5, raise the temperature to 50 °C, and maintain the stirring speed at 200 r / min for 2 h of aging treatment to obtain a pretreated polyaluminum chloride solution. (2) Dissolve 0.5 g of carboxymethyl starch in 50 g of water and add the pretreated polyaluminum chloride solution to mix. Adjust the pH of the mixed system to 5.0 and stir the reaction at 50 °C for 3 h to obtain the reaction solution. (3) The reaction solution was allowed to stand at 40°C for 24 h, and then spray-dried at an inlet temperature of 200°C and an outlet temperature of 90°C to obtain modified polyaluminum chloride-1.

[0030] Preparation Example 2 Preparation of modified polyaluminum chloride: (1) Dissolve 5 g of polyaluminum chloride-1 in 30 g of water to obtain a polyaluminum chloride aqueous solution. Adjust the pH of the polyaluminum chloride aqueous solution to 4.0 and heat it to 70 °C. Keep the stirring speed at 300 r / min and perform aging treatment for 1 h to obtain a pretreated polyaluminum chloride solution. (2) Dissolve 0.5 g of carboxymethyl starch in 50 g of water and add the pretreated polyaluminum chloride solution to mix. Adjust the pH of the mixed system to 6.0 and stir at 70 °C for 1 h to obtain the reaction solution. (3) The reaction solution was allowed to stand at 50°C for 18 h, and then spray-dried at an inlet temperature of 160°C and an outlet temperature of 70°C to obtain modified polyaluminum chloride-2.

[0031] Preparation Example 3 The preparation method was carried out as in Example 1, except that in step (1), 6 g of polyaluminum chloride-2 was dissolved in 30 g of water to obtain an aqueous solution of polyaluminum chloride, thereby obtaining modified polyaluminum chloride-3.

[0032] Preparation Example 4 The preparation method was carried out in accordance with Example 1, except that polyaluminum chloride 1 was completely replaced with polyaluminum chloride-3 to obtain modified polyaluminum chloride-4.

[0033] Preparation Example 5 The preparation method was carried out in accordance with Example 1, except that all of the polyaluminum chloride 1 was replaced with polyaluminum chloride-4 to obtain modified polyaluminum chloride-5. Example 1

[0034] An additive for recycling photoresist waste liquid, wherein the total mass of the raw material components of the additive is 100%, the raw material components of the additive include: 20% water, 10% sodium hydroxide solution (mass concentration of 30%) and 70% N-methylpyrrolidone, the photoresist waste liquid is photoresist waste liquid-2, and the amount of the additive added is 1.5% of the content of the photoresist waste liquid. Example 2

[0035] An additive for recycling photoresist waste liquid, wherein the raw material components of the additive are 100% by weight, and the raw material components of the additive include: 15% water, 5% sodium hydroxide solution (mass concentration of 30%), 79.99% N-methylpyrrolidone and 0.01% polyaluminum chloride-1, wherein the photoresist waste liquid is photoresist waste liquid-1, and the amount of the additive added is 1.2% of the content of the photoresist waste liquid. Example 3

[0036] An additive for recycling photoresist waste liquid, wherein the raw material components of the additive are 100% by weight, and the raw material components of the additive include: 10% water, 10% sodium hydroxide solution (mass concentration of 30%), 79.99% N-methylpyrrolidone and 0.01% modified polyaluminum chloride-1, wherein the photoresist waste liquid is photoresist waste liquid-1, and the amount of the additive added is 1.0% of the content of the photoresist waste liquid. Example 4

[0037] The method described in Example 3 was followed, except that 0.01% modified polyaluminum chloride-1 was completely replaced with 0.01% modified polyaluminum chloride-2. Example 5

[0038] The method described in Example 3 was followed, except that all 0.01% modified polyaluminum chloride-1 was replaced with 0.01% modified polyaluminum chloride-3. Example 6

[0039] An additive for recycling photoresist waste liquid, wherein the raw material components of the additive are 100% by weight, and the raw material components of the additive include: 10% water, 10% sodium hydroxide solution (mass concentration of 30%), 79.99% N-methylpyrrolidone and 0.01% modified polyaluminum chloride-4, the photoresist waste liquid is photoresist waste liquid-1, and the amount of the additive added is 0.8% of the content of the photoresist waste liquid. Example 7

[0040] The method described in Example 3 was followed, except that all 0.01% modified polyaluminum chloride-1 was replaced with 0.01% modified polyaluminum chloride-5.

[0041] Comparative Example 1 The additive is implemented in accordance with Example 1, except that the raw material components include: 5% water, 15% sodium hydroxide solution (mass concentration of 30%) and 80% N-methylpyrrolidone.

[0042] Comparative Example 2 The additive was implemented in accordance with Example 1, except that the raw material components of the additive included: 36% water, 10% sodium hydroxide solution (mass concentration of 30%) and 54% N-methylpyrrolidone.

[0043] Comparative Example 3 The method is implemented in accordance with Example 1, except that the amount of additive added is 0.3% of the content of the photoresist waste liquid.

[0044] Comparative Example 4 The method is implemented in accordance with Example 1, except that the amount of additive added is 2.5% of the content of the photoresist waste liquid.

[0045] Application Example 1 A method for recycling photoresist waste liquid, the method comprising the following steps: S1. The photoresist waste liquid-2 is introduced into the reactor, and water containing the additive described in Example 1 is added to the reactor and stirred to obtain the first mixed system; S2. Add sodium hydroxide solution and N-methylpyrrolidone of the additive described in Example 1 to the first mixed system to obtain a second mixed system. Adjust the pH of the second mixed system to 8, then let the second mixed system stand and settle, and then filter the settled system. S3. Distill the filtrate obtained in step S2 to obtain acetone and butanone products respectively.

[0046] Application Example 2 A method for recycling photoresist waste liquid, the method comprising the following steps: S1. Photoresist waste liquid-1 is introduced into the reactor, and water containing the additive described in Example 2 is added to the reactor and stirred to obtain the first mixed system; S2. Add sodium hydroxide solution and N-methylpyrrolidone of the additives described in Example 2 to the first mixed system to obtain a second mixed system. Adjust the pH of the second mixed system to 8, then let the second mixed system stand and settle. Then add polyaluminum chloride-1 described in Example 2 to the settled system, stir until flocculation is complete, and filter the flocculent. S3. Distill the filtrate obtained in step S2 to obtain acetone and butanone products respectively.

[0047] Application Example 3 The application is carried out in the manner described in Example 2, except that all the additives described in Example 2 are replaced with the additives described in Example 3.

[0048] Application Example 4 The application is carried out in the manner described in Example 2, except that all the additives described in Example 2 are replaced with the additives described in Example 4.

[0049] Application Example 5 The application is carried out in the manner described in Example 2, except that all the additives described in Example 2 are replaced with the additives described in Example 5.

[0050] Application Example 6 The application is carried out in the manner described in Example 2, except that all the additives described in Example 2 are replaced with the additives described in Example 6.

[0051] Application Example 7 The application is carried out in the manner described in Example 2, except that all the additives described in Example 2 are replaced with the additives described in Example 7.

[0052] Application Comparative Example 1 The application was carried out in the manner described in Example 1, except that all the additives described in Example 1 were replaced with the additives described in Comparative Example 1.

[0053] Application Comparative Example 2 The application was carried out in the manner described in Example 1, except that all the additives described in Example 1 were replaced with the additives described in Comparative Example 2.

[0054] Application Comparative Example 3 The application was carried out in the manner described in Example 1, except that all the additives described in Example 1 were replaced with the additives described in Comparative Example 3.

[0055] Application Comparative Example 4 The application was carried out in the manner described in Example 1, except that all the additives described in Example 1 were replaced with the additives described in Comparative Example 4.

[0056] Application Comparative Example 5 The method described in Application Example 1 is followed, except that the alkali is added first, followed by the water. Specifically: S1. Photoresist waste liquid-2 is introduced into the reactor, and sodium hydroxide solution of the additive described in Example 1 is added to the reactor and stirred to obtain the first mixed system; S2. Add water and N-methylpyrrolidone, the additives described in Example 1, to the first mixed system to obtain a second mixed system. Adjust the pH of the second mixed system to 8, then let the second mixed system stand and settle, and then filter the settled system. S3. Distill the filtrate obtained in step S2 to obtain acetone and butanone products respectively.

[0057] Test case Acetone recovery rate (%) = Acetone content in photoresist waste liquid / Acetone product content after distillation; Methyl ketone recovery rate (%) = Methyl ketone content in photoresist waste liquid / Methyl ketone product content after distillation.

[0058] The contents of acetone and butanone products in Application Examples 1-7 and Comparative Examples 1-5 were determined respectively. The acetone recovery rate and butanone recovery rate in Application Examples 1-7 and Comparative Examples 1-5 were calculated based on the acetone recovery rate and butanone recovery rate, respectively. The results are shown in Table 1. Table 1

[0059] As can be seen from Table 1, this application uses a certain amount of water, alkali and N-methylpyrrolidone as additives to recover acetone and butanone from photoresist waste liquid containing specific components, which produces a synergistic effect. The recovery rates of acetone and butanone are relatively high. However, when the content of water, alkali or N-methylpyrrolidone in the additive is not within the specified range, or when the amount of additive added is not within the preset range, the recovery rates of acetone and butanone are relatively low.

[0060] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application.

Claims

1. An additive for recycling photoresist waste liquid, characterized in that, Based on the total mass of the raw material components of the additive being 100%, the raw material components of the additive include: 10-20% water, 5-10% alkaline solution and 70-85% N-methylpyrrolidone, wherein the photoresist waste liquid contains acetone, butanone, ethylene glycol methyl ether, water and epoxy resin, the amount of the additive added is 0.5-2% of the content of the photoresist waste liquid, and the mass ratio of water in the additive to the mass of epoxy resin in the photoresist waste liquid is <3:

1.

2. The additive for recycling photoresist waste liquid according to claim 1, characterized in that, Based on the total mass of the photoresist waste liquid as 100%, the content of acetone is 10-90%, the content of butanone is 0.5-55%, the content of ethylene glycol methyl ether is 0.1-5%, the content of water is 0.1-80%, and the content of epoxy resin is 0.5-50%, wherein the epoxy resin is polyepoxychloropropane.

3. The additive for recycling photoresist waste liquid according to claim 2, characterized in that, The weight-average molecular weight of the polyepoxychloropropane is 500,000 to 700,000.

4. The additive for recycling photoresist waste liquid according to claim 2 or 3, characterized in that, Based on the total mass of the photoresist waste liquid as 100%, when the content of acetone is 30-50%, the content of butanone is 10-25%, the content of ethylene glycol methyl ether is 1-5%, the content of water is 5-20%, and the content of epoxy resin is >30%, the raw materials of the additive also include polyaluminum chloride. Based on the total mass of the raw material components of the additive as 100%, the raw material components include: 10-15% water, 5-10% alkali solution, 75-84% N-methylpyrrolidone, and 0.01% polyaluminum chloride.

5. The additive for recycling photoresist waste liquid according to claim 4, characterized in that, The polyaluminum chloride is a modified polyaluminum chloride, and the raw materials of the modified polyaluminum chloride include polyaluminum chloride and carboxymethyl starch in a mass ratio of 8~12:1, wherein the content of Al2O3 in the polyaluminum chloride is 12~28%.

6. The additive for recycling photoresist waste liquid according to claim 5, characterized in that, The preparation method of the modified polyaluminum chloride includes the following steps: (1) Adjust the pH of the polyaluminum chloride aqueous solution to 3.5~4.0, heat it to 50~70 ℃, keep the stirring speed at 200~300 r / min, and perform aging treatment for 1~2 h to obtain pretreated polyaluminum chloride solution; (2) Dissolve carboxymethyl starch in water and add the pretreated polyaluminum chloride solution to mix. Stir the mixture at 50-70 °C and pH 5.0-6.0 for 1-3 h to obtain the reaction solution. (3) The reaction solution is allowed to stand at 40~50 ℃ for 18~24 h, and then spray-dried at an inlet temperature of 160~200 ℃ and an outlet temperature of 70~90 ℃ to obtain modified polyaluminum chloride.

7. The additive for recycling photoresist waste liquid according to claim 6, characterized in that, The amount of the additive added is 0.8 to 1.2% of the content of the photoresist waste liquid.

8. A method for recycling photoresist waste liquid, characterized in that, The recycling method includes the following steps: S1. The photoresist waste liquid according to any one of claims 1 to 7 is introduced into a reaction vessel, and water containing the additive according to any one of claims 1 to 7 is added to the reaction vessel and stirred to obtain a first mixed system; S2. Add the alkaline solution of the additive described in any one of claims 1 to 7 and N-methylpyrrolidone to the first mixed system to obtain a second mixed system. Allow the second mixed system to stand and settle, and then filter the settled system. S3. Distill the filtrate obtained in step S2 to obtain acetone and butanone products respectively.

9. The method for recycling photoresist waste liquid according to claim 8, characterized in that, In the photoresist waste liquid, when the content of the epoxy resin is >30%, before filtering the settled system, the polyaluminum chloride of any one of claims 4 to 6 is added to the settled system.

10. The method for recycling photoresist waste liquid according to claim 8, characterized in that, In step S2, the pH value of the second mixture is 7-9.

Images