TWI842314B - Method and device for reclaim tetramethylammonium hydroxide in the developing waste liquid and removal of nitrogen-containing compounds - Google Patents

Abstract

A method for recovering tetramethylammonium hydroxide in developing waste liquid and removing nitrogen-containing compounds, comprising a first adsorption step, a first control step, a second control step, and a third control step. In the first adsorption step, a first ion resin is used to adsorb tetramethylammonium hydroxide and nitrogen-containing compounds in a developing waste liquid. In the first control step, the waste developing liquid is controlled to flow into the first ion resin at a high pH value and a high flow rate, to desorb nitrogen-containing compounds in the first ion resin. In the second control step, after the nitrogen-containing compound in the first ion resin is desorbed, the flow of the developing waste liquid is stopped. In the third control step, the first ion resin is regenerated to obtain a recovered solution of tetramethylammonium hydroxide.

Description

Method and device for recovering tetramethylammonium hydroxide from waste developer solution and removing nitrogen-containing compounds

The present invention relates to a method for recovering waste developer liquid, and in particular to a method and a device for recovering tetramethylammonium hydroxide in waste developer liquid and removing nitrogen-containing compounds.

Alkaline developer contains tetramethylammonia hydroxide (TMAH). In order to save resources, manufacturers use a recycling system to recycle the alkaline developer after use. This can solve environmental protection issues on the one hand, and reduce resource consumption on the other hand, thereby saving costs.

In addition to the tetramethylammonium ions (TMA+) generated by the reaction of the developer components, the waste developer liquid used in the early stage will also contain dissolved photoresist, monovalent/polyvalent metal ions (such as sodium, iron and aluminum ions, etc.), inorganic anions, organic anions, surfactants and suspended particles, etc.

In the invention patents No. I366076 and No. I462770 of Taiwan, the inventor proposed a new and highly efficient method for recovering tetramethylammonium hydroxide (TMAH) from developer waste liquid, which mainly includes the steps of "photoresist removal", "deionization", "regeneration", "purification", "electrodialysis" and "concentration adjustment". Among them, "photoresist removal" can be judged whether to be implemented according to the level of photoresist content in the developer waste liquid. For example, if the photoresist content in the developer waste liquid used in the integrated circuit manufacturing industry is relatively low, it can be omitted.

In the "deionization" step, tetramethylammonium ions in a developer waste solution are extracted by using an ion exchange resin, and then a staged regeneration method and device are used to simultaneously regenerate the resin tower during the adsorption process of the developer waste solution, so that the tetramethylammonium ions and the ion exchange resin are separated. The obtained tetramethylammonium ion solution will not contain most of the other impurities in the developer waste solution, which can reduce the adverse interference effects of subsequent purification and electrodialysis.

However, as integrated circuit processes become smaller and smaller in response to consumer demand, the size of each component of these electronic devices must also be reduced. Therefore, progress in the field of photolithography is necessary for the ability to miniaturize the device. Therefore, the chemicals used in the process need to be continuously refined, such as adding other nitrogen-containing compounds to improve performance. However, the well-known steps of recycling developer waste liquid such as "photoresist removal", "deionization", "regeneration", "purification" and "electrodialysis" cannot effectively remove other nitrogen-containing compounds, so that the recovered tetramethylammonium hydroxide (TMAH) also contains impurities such as other nitrogen-containing compounds. At the same time, these impurities will also interfere with the quality of subsequent electrodialysis.

In view of the above problems, it is hoped that an operating method and equipment can be developed to recover tetramethylammonium ions without other nitrogen-containing compounds, so as to reduce the operating costs of back-end purification and electrodialysis and produce tetramethylammonium hydroxide with higher purity. This is a goal that relevant technical personnel urgently need to work hard on.

In view of this, one object of the present invention is to provide a method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid. The method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid comprises a first adsorption step, a first control step, a second control step, and a third control step.

In the first adsorption step, a developer waste liquid in a container is injected into a first ionic resin at a first flow rate, and the first ionic resin adsorbs tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste liquid, and a first filter liquid flows out.

In the first control step, when the pH value of the first filter solution is greater than or equal to a first pH setting value, the flow rate of the developer waste liquid injected into the first ionic resin is increased to a second flow rate, thereby desorbing the nitrogen-containing compound in the first ionic resin.

In the second control step, when the conductivity of the developer waste liquid is similar to the conductivity of the first filter liquid, the injection of the developer waste liquid into the first ionic resin is stopped.

In the third control step, an acidic solution is applied to the first ionic resin to desorb tetramethylammonium hydroxide from the first ionic resin to obtain a tetramethylammonium salt solution.

Another technical means of the present invention is that in the first adsorption step, the first flow rate is 2 BV/hr, and in the first control step, the second flow rate is greater than or equal to 4 BV/hr.

Another technical means of the present invention is that in the above-mentioned first control step, the first acid-base setting value is 7.

Another technical means of the present invention is that the above-mentioned method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in the developer waste liquid further includes a second adsorption step after the first adsorption step. In the second adsorption step, when the conductivity of the developer waste liquid is different from the conductivity of the first filter liquid, the first filter liquid is injected into a second ionic resin to adsorb the tetramethylammonium hydroxide and nitrogen-containing compounds in the first filter liquid, and a second filter liquid is discharged.

Another technical means of the present invention is that the above-mentioned method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in the developer waste liquid further includes an ion exchange step after the second adsorption step, and a resin regeneration step after the ion exchange step. In the ion exchange step, when the acidity and alkalinity of the second filter liquid are greater than or equal to a second acidity and alkalinity setting value, the injection of the first filter liquid into the second ion resin is stopped, and an alkaline solution is used for the second ion resin. In the resin regeneration step, the injection of the alkaline solution into the second ion resin is stopped, and an acidic solution is used for the second ion resin.

Another technical means of the present invention is that in the above-mentioned ion exchange step, the second acid-base setting value is 7, and the concentration of the alkaline solution is 0.1%-2%.

Another technical means of the present invention is that the above-mentioned method for recovering tetramethylammonium hydroxide in the developer waste liquid and removing nitrogen-containing compounds further includes a waste liquid discharge step after the ion exchange step, and a waste liquid recovery step between the waste liquid discharge step and the resin regeneration step. In the waste liquid discharge step, when the conductivity of the alkaline solution flowing out of the second ion resin is less than a conductivity setting value, the second filtered liquid is discharged to the outside, and in the waste liquid recovery step, when the conductivity of the alkaline solution flowing out of the second ion resin is equal to or greater than the conductivity setting value, the alkaline solution flowing out of the second ion resin is returned to the container.

Another technical means of the present invention is that in the above-mentioned waste liquid discharge step and the waste liquid recovery step, the conductivity setting value is 400us/cm.

Another object of the present invention is to provide a device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid. The device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid is applicable to the method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid as described above. The device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid comprises a circulation unit and a first adsorption unit.

The circulation unit includes a container and a water pump module connected to the container, and the container is used to accommodate a developer waste liquid.

The first adsorption unit includes a first ionic resin connected to the container, a first acidity sensing module arranged at the outlet of the first ionic resin, a first conductivity sensing module arranged at the inlet of the first ionic resin, a second conductivity sensing module arranged at the outlet of the first ionic resin, a first regeneration module arranged at the inlet of the first ionic resin, and a first valve module arranged at the outlet of the first ionic resin.

The water pump module is used to inject the developer waste liquid into the first ion resin, the first regeneration module is used to inject the acid solution into the first ion resin, and the first valve module is used to control the liquid output by the first ion resin to be discharged outward or guided back to the container.

Another object of the present invention is to provide another device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid. The device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid is applicable to the above-mentioned method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid. The device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid comprises a circulation unit, a first adsorption unit, and a second adsorption unit.

The circulation unit includes a container and a water pump module connected to the container, and the container is used to accommodate a developer waste liquid.

The first adsorption unit includes a first ionic resin disposed at the outlet of the container, a first acidity and alkalinity sensing module disposed at the outlet of the first ionic resin, a first conductivity sensing module disposed at the inlet of the first ionic resin, a second conductivity sensing module disposed at the outlet of the first ionic resin, a first regeneration module disposed at the inlet of the first ionic resin, and a first valve module disposed at the outlet of the first ionic resin. The water pump module is used to inject the developer waste liquid into the first ionic resin, and the first regeneration module is used to inject an acidic solution into the first ionic resin.

The second adsorption unit includes a second ionic resin disposed between the first ionic resin outlet and the container inlet, a second acidity and alkalinity sensing module disposed at the second ionic resin outlet, a third conductivity sensing module disposed at the second ionic resin outlet, an alkaline liquid supply module disposed at the second ionic resin inlet, a second regeneration module disposed at the second ionic resin inlet, and a second valve module disposed at the second ionic resin outlet.

The alkaline liquid supply module is used to inject alkaline solution into the second ion resin, the second regeneration module is used to inject acidic solution into the second ion resin, the first valve module is used to control the liquid output from the first ion resin to be discharged to the outside or injected into the second ion resin, and the second valve module is used to control the liquid output from the second ion resin to be discharged to the outside or introduced back into the container.

The beneficial effect of the present invention is that in the first adsorption step, as the first ionic resin adsorbs tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste liquid, the first filter liquid will increase its pH value due to the increase in the saturation of the first ionic resin. Since the dissociation constant of nitrogen-containing compounds is much smaller than that of tetramethylammonium hydroxide, when the pH value of the first filter liquid is greater than or equal to the first pH setting value, the tetramethylammonium hydroxide in the developer waste liquid will react with the nitrogen-containing compounds in the first ionic resin. Ion exchange can remove nitrogen-containing compounds in the first ionic resin, thereby achieving the purpose of reducing the nitrogen-containing compounds in the first ionic resin and increasing the content of tetramethylammonium hydroxide in the first ionic resin, so as to effectively reduce the nitrogen-containing compounds in the tetramethylammonium salt solution discharged and obtained in the third control step, and further reduce the burden of the back-end process, while not affecting the total amount of tetramethylammonium hydroxide in the tetramethylammonium salt solution discharged and obtained when the first ionic resin is regenerated by the acidic solution.

The related patent application features and technical contents of the present invention will be clearly presented in the following detailed description of two preferred embodiments with reference to the drawings. Before the detailed description, it should be noted that similar components are represented by the same numbers.

Referring to FIG. 1 , a first preferred embodiment of a device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid of the present invention is shown. The device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds comprises a circulation unit 31 and a first adsorption unit 32.

The circulation unit 31 includes a container 311, a circulation pipeline 312 connected to the container 311, and a water pump module 313 connected to the container 311. The container 311 is used to accommodate a developer waste liquid. The water pump module 313 is used to drive the developer waste liquid to flow in the circulation pipeline 312, and the water pump module 313 can control the flow rate of the developer waste liquid in the ion resin in the first adsorption unit 32. Since controlling the flow rate of the liquid in the pipeline is a known technology, it will not be described in detail here.

The first adsorption unit 32 includes a first ionic resin 321 connected to the container 311 and having an inlet (not shown in the figure) and an outlet (not shown in the figure), a first acidity sensing module 322 disposed at the outlet of the first ionic resin 321, a first conductivity sensing module 323 disposed at the inlet of the first ionic resin 321, a second conductivity sensing module 324 disposed at the outlet of the first ionic resin 321, a first regeneration module 325 disposed at the inlet of the first ionic resin 321, and a first valve module 326 disposed at the outlet of the first ionic resin 321.

The water pump module 313 is used to inject the developer waste liquid into the first ion resin 321, the first pH sensing module 322 is used to detect the pH value of the first filter liquid, the first conductivity sensing module 323 is used to detect the conductivity value of the developer waste liquid, the second conductivity sensing module 324 is used to detect the conductivity value of the first filter liquid, the first regeneration module 325 is used to inject an acid solution into the first ion resin 321, and the first valve module 326 is used to control the liquid output from the first ion resin 321 to be discharged to the outside or guided back to the container 311.

In the first preferred embodiment, after the circulation pipeline 312 is connected from the container 311, it passes through the water pump module 313, the first pH sensing module 322, the first ionic resin 321, the first conductivity sensing module 323, the second conductivity sensing module 324, and the first valve module 326 in sequence and then is connected back to the container 311 to form a circulation pipeline 312 that can circulate the developer waste liquid. During actual implementation, the pipeline configuration of the circulation pipeline 312 can also be configured according to the actual site and should not be limited to this.

The first ion resin 321 uses a plurality of cationic ion exchange resin towers. In the first preferred embodiment, the first ion resin 321 uses three resin towers. The resin towers of the first ion resin 321 can be arranged in series or in parallel. Since the arrangement of the resin towers and the connecting pipes are known techniques, they will not be described in detail here. In actual implementation, the first ion resin 321 can even be arranged in multiple groups. When one group of the first ion resin 321 is performing ion exchange, another group of the first ion resin 321 can perform a regeneration process, and another group of the first ion resin 321 is waiting for standby after completing regeneration. The example of the preferred embodiment should not be limited to this. The first valve module 326 is electrically connected to the water pump module 313, the first pH sensing module 322, the first conductivity sensing module 323, the second conductivity sensing module 324, and the first regeneration module 325, respectively, wherein the first valve module 326 is a module device having a control circuit and a water valve element.

Please refer to FIG. 2 for a method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds from developer waste liquid. The method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds from developer waste liquid corresponds to the above-mentioned device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds from developer waste liquid. The method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds from developer waste liquid includes a first adsorption step 901, a first control step 902, a second control step 903, and a third control step 904.

In the first adsorption step 901, the developer waste liquid in the container 311 is injected into the first ion resin 321 at a first flow rate. The first ion resin 321 adsorbs tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste liquid, and flows out the first filter liquid. The first pH sensing module 322 senses the pH value of the first filter liquid. When the first ion resin 321 with a stronger adsorption force performs ion adsorption, it can adsorb more tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste liquid. At this time, the pH value measured by the first pH sensing module 322 is lower. As the adsorption capacity of the first ion resin 321 weakens, the pH value of the first filter liquid increases. , the pH value of the first filter liquid gradually increases. When the pH value of the first filter liquid flowing out of the first ion resin 321 is less than a first pH setting value, it is determined that the standard of the first filter liquid meets the discharge regulations and can be directly discharged into a wastewater treatment system. The first valve module 326 controls the first filter liquid flowing out of the first ion resin 321 to flow to the wastewater treatment system. At this time, the water pump module 313 controls the developer waste liquid to flow into the first ion resin 321 at a first flow rate. Preferably, the first flow rate in the first ion resin 321 controlled by the water pump module 313 is controlled at 2BV/hr.

In the first control step 902, when the acidity and alkalinity of the first filter liquid is greater than or equal to the first acidity and alkalinity setting value, the flow rate of the developer waste liquid injected into the first ionic resin 321 is increased to a second flow rate, thereby desorbing the nitrogen-containing compounds in the first ionic resin 321, and the first valve module 326 controls the first filter liquid flowing out of the first ionic resin 321 to flow back to the container 311, and The flow rate of the developer waste liquid injected into the first ionic resin 321 is increased to a second flow rate, wherein, since the pH of the first filter liquid has been increased to the first pH setting value, the nitrogen-containing compounds in the first ionic resin 321 can be desorbed. Preferably, the water pump module 313 controls the second flow rate in the first ionic resin 321 to be controlled at 4 BV/hr or greater than 4 BV/hr.

In the first preferred embodiment, the first acid-base setting value is 7. In actual implementation, the first flow rate and the second flow rate in the first ionic resin 321, as well as the setting value of the first acid-base setting value, should be set according to actual conditions and should not be limited thereto. Since the dissociation constant of nitrogen-containing compounds is much smaller than that of tetramethylammonium hydroxide, when the acidity and alkalinity of the first filter liquid has been increased to the first acid-base setting value and the flow rate is increased to the second flow rate, the tetramethylammonium hydroxide in the developer waste liquid will exchange the nitrogen-containing compounds in the first ionic resin 321, thereby reducing the nitrogen-containing compounds in the first ionic resin 321.

In the second control step 903, when the nitrogen-containing compounds in the first ionic resin 321 begin to be desorbed, the first filter liquid will contain many nitrogen-containing compounds, which will cause the conductivity of the developer waste liquid to be greatly different from that of the first filter liquid. Since the conductivity of nitrogen-containing compounds is lower than that of tetramethylammonium hydroxide, the conductivity of the first filter liquid is lower than that of the developer waste liquid. When the nitrogen-containing compounds in the first ionic resin 321 have been reduced, the first filter liquid will not contain or contain a small amount of nitrogen-containing compounds, and the conductivity of the developer waste liquid will be very close to the conductivity of the first filter liquid. Therefore, when the conductivity of the developer waste liquid is close to (substantially the same as) the conductivity of the first filter liquid, the developer waste liquid is stopped from being injected into the first ionic resin 321. Since the conductivity of the developer waste liquid is not a fixed value, the conductivity of the first filter liquid flowing out of the first ionic resin 321 will change with the conductivity of the first filter liquid. As the adsorption capacity of the first ionic resin 321 decreases, it gradually increases. Therefore, when the conductivity of the first filter liquid is close to (substantially the same as) the conductivity of the developer waste liquid, it means that the nitrogen-containing compound in the first ionic resin 321 has been released. Then, the developer waste liquid is stopped from being injected into the first ionic resin 321, and the third control step 904 is entered. In actual implementation, the water pump module 313 can also guide the developer waste liquid to another set of regenerated first ionic resin 321, but it should not be limited to this.

In the third control step 904, the first regeneration module 325 is controlled to use an acidic solution on the first ionic resin 321 to desorb tetramethylammonium hydroxide in the first ionic resin 321, and to discharge and obtain a tetramethylammonium salt solution. When the first regeneration module 325 regenerates the first ionic resin 321, the first valve module 326 controls the tetramethylammonium salt solution to enter a recovery system, and the recovery system can further separate the tetramethylammonium hydroxide in the tetramethylammonium salt solution. Since the tetramethylammonium salt solution no longer contains or greatly reduces nitrogen-containing compounds, the subsequent regeneration process can be reduced. The cost of the process is reduced. When the first ion resin 321 is ready for use after regeneration, the regenerated first ion resin 321 can adsorb tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste liquid in the first adsorption step 901, so as to sequentially perform the first adsorption step 901, the first control step 902, the second control step 903 and the third control step 904.

Wherein, in the first adsorption step 901, the first flow rate is 2BV/hr, in the first control step 902, the second flow rate is 4BV/hr, and in the first control step 902, the first acid-base setting value is 7, which should not be limited to the actual implementation.

Referring to FIG. 3 , a second preferred embodiment of a device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid of the present invention is shown. The second preferred embodiment is substantially the same as the first preferred embodiment. The device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds comprises a circulation unit 31, a first adsorption unit 32, and a second adsorption unit 33.

The circulation unit 31 includes a container 311, a circulation pipeline 312 connected to the container 311, and a water pump module 313 connected to the container 311. The container 311 is used to accommodate a developer waste liquid, and the water pump module 313 is used to drive the developer waste liquid to flow in the circulation pipeline 312.

The first adsorption unit 32 includes a first ionic resin 321 connected to the container 311 and having an inlet (not shown in the figure) and an outlet (not shown in the figure), a first acidity sensing module 322 disposed at the outlet of the first ionic resin 321, a first conductivity sensing module 323 disposed at the inlet of the first ionic resin 321, a second conductivity sensing module 324 disposed at the outlet of the first ionic resin 321, a first regeneration module 325 disposed at the inlet of the first ionic resin 321, and a first valve module 326 disposed at the outlet of the first ionic resin 321.

The second adsorption unit 33 includes a second ionic resin 331 disposed between the outlet of the first ionic resin 321 and the inlet of the container 311 and having an inlet (not shown in the figure) and an outlet (not shown in the figure), a second acidity and alkalinity sensing module 332 disposed at the outlet of the second ionic resin 331, a third conductivity sensing module 333 disposed at the outlet of the second ionic resin 331, an alkaline liquid supply module 334 disposed at the inlet of the second ionic resin 331, a second regeneration module 335 disposed at the inlet of the second ionic resin 331, and a second valve module 336 disposed at the outlet of the second ionic resin 331.

The water pump module 313 is used to inject the developer waste liquid into the first ion resin 321, the first pH sensing module 322 is used to detect the pH value of the first filter liquid, the first conductivity sensing module 323 is used to detect the conductivity value of the developer waste liquid, the second conductivity sensing module 324 is used to detect the conductivity value of the first filter liquid, the first regeneration module 325 is used to inject an acid solution into the first ion resin 321, and the first valve module 326 is used to control the liquid output from the first ion resin 321 to be discharged outward. The second ionic resin 331 is output or injected into the second ionic resin 331, the second pH sensing module 332 is used to detect the pH value of the second filter liquid, the third conductivity sensing module 333 is used to detect the conductivity value of the second filter liquid, the alkaline solution supply module 334 is used to inject an alkaline solution into the second ionic resin 331, the second regeneration module 335 is used to inject an acidic solution into the second ionic resin 331, and the second valve module 336 is used to control the liquid output from the second ionic resin 331 to be discharged to the outside or introduced back into the container 311.

After the circulation pipe 312 is connected from the container 311, it passes through the first ion resin 321 and the second ion resin 331 in sequence and then is connected back to the container 311, and the water pump module 313 drives the developer waste liquid to circulate in the circulation pipe 312. In addition, the water pump module 313 can also control the flow rate of the developer waste liquid in the circulation pipe 312. In a second preferred embodiment, the water pump module 313 has a plurality of pressurized water pumps, which are respectively arranged between the water pump and the first ion resin 321, between the first ion resin 321 and the second ion resin 331, and between the second ion resin 331 and the container 311. In actual implementation, the arrangement of the water pump module 313 should be based on the actual pipeline and should not be limited thereto.

The first ion resin 321 and the second ion resin 331 use multiple cationic ion exchange resin towers. Preferably, the first ion resin 321 uses three resin towers, and the second ion resin 331 uses two resin towers. The resin towers of the first ion resin 321 can be arranged in series or in parallel, and the resin towers of the second ion resin 331 can be arranged in series or in parallel. Since the setting of the resin tower is a known setting, it will not be described in detail here. In actual implementation, the first ion resin 321 and the second ion resin 331 can be set with multiple sets of resin towers. When one set of resin towers is performing ion exchange of nitrogen-containing compounds, another set of resin towers can perform a regeneration process, and another set of resin towers is waiting for a standby process after completing the regeneration process. It should not be limited to the examples of this preferred embodiment.

The first valve module 326 is electrically connected to the water pump module 313, the first pH sensing module 322, the first conductivity sensing module 323, the second conductivity sensing module 324, and the first regeneration module 325, respectively. The second valve module 336 is electrically connected to the water pump module 313, the second pH sensing module 332, the third conductivity sensing module 333, the alkaline liquid supply module 334, and the second regeneration module 335, respectively. The first valve module 326 and the second valve module 336 have a control circuit and a water valve element.

The first valve module 326 is disposed in the circulation pipeline 312 and is located between the first ion resin 321 and the second ion resin 331, and the first valve module 326 is additionally connected to an external pipeline to connect to a wastewater treatment system (not shown in the figure) and a recovery system (not shown in the figure). The second valve module 336 is disposed in the circulation pipeline 312 and is located between the second ion resin 331 and the container 311. The second valve module 336 is additionally connected to an external pipeline to connect to the wastewater treatment system, wherein the wastewater treatment system and the recovery system can be the same treatment system, but should not be limited to this.

Please refer to FIG. 4 for a method for recovering tetramethylammonium hydroxide in developer waste liquid and removing nitrogen-containing compounds corresponding to the above-mentioned device. The method for recovering tetramethylammonium hydroxide in developer waste liquid and removing nitrogen-containing compounds comprises a first adsorption step 901, a first control step 902, a second control step 903, a third control step 904, a second adsorption step 905, an ion exchange step 906, a waste liquid discharge step 907, a waste liquid recovery step 908, and a resin regeneration step 909.

In the first adsorption step 901, the water pump module 313 is controlled to inject the developer waste liquid in the container 311 into the first ionic resin 321. The first ionic resin 321 adsorbs tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste liquid. The first ionic resin 321 flows out a first filter liquid. The pH value of the first filter liquid gradually increases as the adsorption capacity of the first ionic resin 321 weakens. The first pH sensing module 322 senses the pH value of the first filter liquid flowing out of the first ionic resin 321. When the pH value of the first filtered liquid flowing out of the first ion resin 321 is less than the first pH setting value, the standard of the first filtered liquid meets the discharge regulations and can be directly discharged into the wastewater treatment system. The first valve module 326 controls the first filtered liquid flowing out of the first ion resin 321 to flow to the wastewater treatment system. At this time, the water pump module 313 controls the developer waste liquid to flow into the first ion resin 321 at a first flow rate. Preferably, the water pump module 313 controls the first flow rate in the first ion resin 321 to be controlled at 2BV/hr.

In the first control step 902, when the pH value of the first filter liquid flowing out of the first ionic resin 321 is greater than or equal to the first pH setting value, the first valve module 326 controls the first filter liquid flowing out of the first ionic resin 321 to flow into the second ionic resin 331, and increases the flow rate of the developer waste liquid injected into the first ionic resin 321 to a second flow rate, thereby desorbing the nitrogen-containing compounds in the first ionic resin 321. Preferably, the water pump module 313 controls the second flow rate in the first ionic resin 321 to be controlled at 4 BV/hr or greater than 4 BV/hr. In addition, the first pH setting value is set to 1. The value is 7. In actual implementation, the first flow rate, the second flow rate, and the setting value of the first acid-base setting value in the first ionic resin 321 should be set according to the actual situation and should not be limited thereto. The first conductivity sensing module 323 senses the conductivity of the developer waste liquid, and the second conductivity sensing module 324 senses the conductivity of the first filter liquid. When the conductivity of the first filter liquid is greatly different from that of the developer waste liquid, it means that tetramethylammonium hydroxide in the developer waste liquid is exchanged with the nitrogen-containing compound in the first ionic resin 321, and the first filter liquid has more nitrogen-containing compounds and therefore has a lower conductivity than the developer waste liquid.

In the second control step 903, when the first ionic resin 321 can no longer release nitrogen-containing compounds, the conductivity of the first filter liquid is close to or substantially the same as the conductivity of the developer waste liquid (when the difference between the conductivity of the first filter liquid and the conductivity of the developer waste liquid is between ±2ms/cm, it is defined as the conductivity is close to or substantially the same), and the developer waste liquid is stopped from being injected into the first ionic resin 321. The conductivity is not a fixed value. Therefore, when the conductivity of the first filter liquid is close to (or substantially the same as) the conductivity of the developer waste liquid, it means that the nitrogen-containing compound can no longer be separated from the first ionic resin 321. Therefore, the injection of the developer waste liquid into the first ionic resin 321 is stopped, and the third control step 904 is entered. In actual implementation, the water pump module 313 can guide the developer waste liquid to another set of regenerated first ionic resin 321, but this should not be limited to this.

In the third control step 904, the first regeneration module 325 is controlled to use an acidic solution on the first ionic resin 321 to desorb tetramethylammonium hydroxide in the first ionic resin 321 to obtain a tetramethylammonium salt solution. When the first regeneration module 325 regenerates the first ionic resin 321, the first valve module 326 controls the tetramethylammonium salt solution to enter the recovery system. The recovery system can The tetramethylammonium hydroxide containing no nitrogen compounds in the tetramethylammonium salt solution is separated. When the first ionic resin 321 is regenerated and ready for use, the first adsorption step 901, the first control step 902, the second control step 903 and the third control step 904 are sequentially performed. The regenerated first ionic resin 321 can adsorb the tetramethylammonium hydroxide and the nitrogen compounds in the developer waste solution in the first adsorption step 901.

In the second preferred embodiment, when the first control step 902 is executed, when the pH of the first filter liquid is greater than or equal to the first pH setting value, not only is the flow rate of the developer waste liquid injected into the first ionic resin 321 increased to the second flow rate to desorb the nitrogen-containing compounds in the first ionic resin 321, but the second adsorption step 905 is also executed.

In the second adsorption step 905, because the pH of the first filter liquid is greater than or equal to the first pH setting value, and the flow rate in the first ionic resin 321 has been increased to the second flow rate, the nitrogen-containing compounds in the first ionic resin 321 will be released, so the first valve module 326 controls the first filter liquid to flow into the second ionic resin 331, so that the second ionic resin 331 adsorbs tetramethylammonium and nitrogen-containing compounds in the first filter liquid, and the second ionic resin 331 discharges a second filter liquid. When the second ionic resin 331 When unsaturated (the pH of the second filtered liquid is less than a second pH setting value), the nitrogen-containing compounds in the first filtered liquid can be effectively adsorbed, so the second filtered liquid meets the discharge standard. The second valve module 336 controls the second filtered liquid to be output to the wastewater treatment system. Even if the first ionic resin 321 circulates to perform the first adsorption step 901, the first control step 902, the second control step 903 and the third control step 904, the second valve module 336 still controls the second filtered liquid to be output to the wastewater treatment system. When the second ion resin 331 is saturated, the injection of the first filter liquid into the second ion resin 331 is stopped immediately. In actual implementation, the first filter liquid can be output to another set of regenerated second ion resin 331, but this should not be limited to it.

When the pH value of the second filtered liquid is greater than or equal to the second pH setting value, it indicates that the second ion resin 331 is saturated, and therefore the ion exchange step 906, the waste liquid discharge step 907, the waste liquid recovery step 908 and the resin regeneration step 909 are sequentially performed. Preferably, the second pH setting value is 7, but it should not be limited thereto in actual implementation.

In the ion exchange step 906, when the acidity and alkalinity of the second filter liquid is greater than or equal to a second acidity and alkalinity setting value, the injection of the first filter liquid into the second ion resin 331 is stopped, and an alkaline solution (sodium hydroxide or potassium hydroxide) is used for the second ion resin 331. The ions (such as sodium ions or potassium ions) contained in the alkaline solution can be ion exchanged with the nitrogen-containing compound or tetramethylammonium ions in the second ion resin 331. This is defined as a pre-regeneration process, so that the alkaline solution discharged from the second ion resin 331 can discharge the nitrogen-containing compound first and then discharge the tetramethylammonium ions. It is worth mentioning that due to The concentration of the alkaline solution used in the previous regeneration process can change the degree of ion exchange. When the concentration of the alkaline solution is within the effective range, the nitrogen-containing compound and tetramethylammonium ions in the second ion resin 331 can be effectively separated. According to the inventor's test, if the concentration of the alkaline solution is too high or too low, the nitrogen-containing compound or tetramethylammonium ions in the second ion resin 331 cannot be effectively released. Preferably, the alkaline solution used for the second ion resin 331 can be sodium hydroxide or potassium hydroxide. In actual implementation, it can also be other alkaline solutions or other alkaline solutions containing sodium hydroxide or potassium hydroxide.

In the second preferred embodiment, the weight percentage concentration of the alkaline solution is 0.1% to 2%. Since the concentration of the alkaline solution used in the previous regeneration process will change the degree of ion exchange; in this concentration range (0.1wt% to 2wt%), the sodium ions or potassium ions in the alkaline solution can exchange ions with the nitrogen-containing compound of the second ion resin 331. In this way, the nitrogen-containing compounds in the second ionic resin 331 are effectively separated from tetramethylammonium ions. In actual implementation, the concentration of the alkaline solution should be adjusted according to the actual situation to discharge the nitrogen-containing compounds and obtain the best recovery effect of tetramethylammonium hydroxide. When the alkaline solution effectively releases the nitrogen-containing compounds in the second ionic resin 331, the waste liquid discharge step 907 is performed.

In the waste liquid discharge step 907, since the second ionic resin 331 is already saturated and an alkaline solution is used for the second ionic resin 331, the step utilizes the characteristic that "the dissociation constant of nitrogen-containing compounds is much smaller than that of tetramethylammonium hydroxide". The ions in the alkaline solution will first exchange with the nitrogen-containing compounds in the second ionic resin 331, but will not exchange with tetramethylammonium ions. Since the conductivity of nitrogen-containing compounds is lower than that of tetramethylammonium hydroxide, when the second ionic resin 331 is saturated, the ions in the alkaline solution will first exchange with the nitrogen-containing compounds in the second ionic resin 331, and will not exchange with tetramethylammonium ions. When the conductivity of the alkaline solution flowing out of the second ionic resin 331 is less than a conductivity setting value, it means that the alkaline solution entering the second ionic resin 331 and the nitrogen-containing compounds in the second ionic resin 331 are effectively undergoing ion exchange, and the solution discharged from the second ionic resin 331 contains a large amount of nitrogen-containing compounds and does not contain tetramethylammonium hydroxide, and the discharged liquid meets the discharge standard. The second valve module 336 discharges the alkaline solution discharged from the second ionic resin 331 into the wastewater treatment system.

In the waste liquid recovery step 908, when the nitrogen-containing compound in the second ion resin 331 has been gradually released by the alkaline solution, only tetramethylammonium ions remain in the second ion resin 331. Then, the ions (such as sodium ions or potassium ions) contained in the alkaline solution can undergo ion exchange with the tetramethylammonium ions in the second ion resin 331. The alkaline solution (sodium hydroxide or potassium hydroxide) is replaced with a solution containing tetramethylammonium hydroxide. Since tetramethylammonium hydroxide has a higher conductivity, the conductivity of the liquid discharged from the second ionic resin 331 will increase. Therefore, when the conductivity of the alkaline solution discharged from the second ionic resin 331 is equal to or greater than the conductivity setting value, it means that The second ion resin 331 is releasing tetramethylammonium hydroxide. At this time, the second valve module 336 guides the solution containing tetramethylammonium hydroxide flowing out of the second ion resin 331 back to the container 311 to recover the tetramethylammonium hydroxide until a fixed amount of alkaline solution flows out. Then, the alkaline solution supply module 334 stops injecting alkaline solution into the second ion resin 331. The conductivity setting value is 400us/cm, the alkaline solution is sodium hydroxide or potassium hydroxide, and the acidic solution is hydrochloric acid. In actual implementation, the first acid-base setting value, the second acid-base setting value, the conductivity setting value, the components used in the alkaline solution, and the components used in the acidic solution should not be limited to this.

In the resin regeneration step 909, the alkaline solution supply module 334 stops injecting the alkaline solution into the second ion resin 331, and the second ion resin 331 is filled with ions provided by the alkaline solution. Then, the second regeneration module 335 is controlled to use an acidic solution on the second ion resin 331. The acidic solution can desorb the second ion resin 3 The ions (such as sodium ions or potassium ions) provided by the alkaline solution in 31 are used to regenerate the second ion resin 331 for standby use. This is defined as a post-regeneration process. Since the technology of regenerating the resin with an acidic solution is well known, it will not be described in detail here. The regenerated second ion resin 331 waits for the second adsorption step 905 to be performed again.

The above method is mainly based on the fact that "the dissociation constant of nitrogen-containing compounds is much smaller than that of tetramethylammonium hydroxide". Therefore, the present invention utilizes the fact that nitrogen-containing compounds are not easy to form cations under high pH (high acidity and alkalinity) conditions, so that tetramethylammonium ions in the developer waste liquid exchange the nitrogen-containing compounds in the first ionic resin 321, thereby removing most of the nitrogen-containing compounds, and then the second ionic resin 331 is used to adsorb this high acidity and alkalinity solution to avoid the problem that the highly alkaline and high nitrogen wastewater cannot be discharged.

In addition, after the second ion resin 331 is saturated, the nitrogen-containing compound is easily exchanged with the cations in the alkaline solution under high acidity and alkalinity conditions, thereby separating and desorbing the nitrogen-containing compound and tetramethylammonium ions to effectively recover the tetramethylammonium ions, thereby achieving the purpose of effectively removing the nitrogen-containing compound and recovering the tetramethylammonium ions. Finally, the acidic solution is used to regenerate the second ion resin 331 for standby use.

Experiment:

In a first experiment, a developer waste liquid with a low concentration of tetramethylammonium ions was used. The developer waste liquid was adsorbed by the first ion resin 321. The concentrations of the compounds in the developer waste liquid and the tetramethylammonium salt solution are shown in Table (I). When the pH value at the outlet of the first ion resin 321 was measured to be greater than 7, the flow rate was increased to 4 BV/hr, and the first valve module 326 was controlled to switch the valve to the second ion resin 331. When the conductivity at the outlet of the first ion resin 321 was equal to the conductivity at the inlet, the flow rate was reduced and the spare tower of the first ion resin 321 was used to continue the adsorption of the developer waste liquid. The adsorption and desorption of the first ion resin 321 can be calculated to have a removal rate of at least 80%. The tetramethylammonium salt solution obtained by regenerating the first ion resin 321 with an acidic solution has ammonium ions (NH ₄ ⁺ ) and monoethanolamine (MEA) less than 10 ppm and 25 ppm, respectively. Therefore, by increasing the pH value of the developer waste solution and increasing the flow rate of the first ion resin 321, the nitrogen-containing compounds (ammonium ions (NH ₄ ⁺ ) and monoethanolamine (MEA)) adsorbed by the first ion resin 321 can be removed, so that the first filter liquid can increase the concentration of the tetramethylammonium salt (TMA ⁺ ) and reduce the concentration of the nitrogen-containing compounds. Detailed data are shown in Table (I).

Concentration of each compound in waste developer solution (ppm) Removal rate (%) Concentration in tetramethylammonium salt solution NH ₄ ⁺ MEA TMA ⁺ NH ₄ ⁺ MEA NH ₄ ⁺ MEA TMA ⁺ 3 46 1359 95 98 ＜10ppm ＜25ppm 10.8% Table 1: Low concentration of tetramethylammonium ion developer wastewater, adsorption operation at high flow rate

In a second experiment, the experimental conditions of the second experiment were substantially the same as those of the first experiment, except that the concentration of tetramethylammonium ions in the developer waste solution was increased in the second experiment (TMA ⁺ increased from 1359 ppm to 3540 ppm). Detailed data are shown in Table (II).

Concentration of each compound in waste developer solution (ppm) Removal rate (%) Concentration in tetramethylammonium salt solution NH ₄ ⁺ MEA TMA ⁺ NH ₄ ⁺ MEA NH ₄ ⁺ MEA TMA ⁺ 8 50 3540 84 95 ＜10ppm ＜25ppm 11.1% Table 2: High concentration of tetramethylammonium ion developer wastewater, adsorption operation at high flow rate

In a third experiment, the experimental conditions of the third experiment were substantially the same as those of the second experiment, except that the concentration of monoethanolamine in the developer waste solution was further increased in the third experiment (MEA was increased from 50 ppm to 123 ppm). Detailed data are shown in Table (III).

Concentration of each compound in waste developer solution (ppm) Removal rate (%) Concentration in tetramethylammonium salt solution NH ₄ ⁺ MEA TMA ⁺ NH ₄ ⁺ MEA NH ₄ ⁺ MEA TMA ⁺ 10 123 4110 74 82 ＜10ppm ＜25ppm 9.8% Table (III) High concentration of tetramethylammonium ion and monoethanolamine developer wastewater, adsorption operation at high flow rate

Then, a fourth experiment was conducted. The fourth experiment was a control experiment. In the fourth experiment, the flow rate of the developer waste liquid was not increased. The developer waste liquid was adsorbed by the first ion resin 321. The concentrations of the compounds in the developer waste liquid and the tetramethylammonium salt solution are shown in Table (IV). When the pH value at the outlet of the first ion resin 321 was measured to be greater than 7, the adsorption was stopped. Then, the first ion resin 321 was regenerated with acid solution. Ammonium ions (NH ₄ ⁺ ) and monoethanolamine (MEA) were detectable in the obtained regenerated recovery solution (tetramethylammonium salt solution). Detailed data is shown in Table (IV). By comparing the fourth experiment with the first to third experiments, it can be seen that if the flow rate is not increased, the removal rate of ammonium ions (NH ₄ ⁺ ) and monoethanolamine (MEA) of the first ion resin 321 will be less than 50%, and ammonium ions (NH ₄ ⁺ ) and monoethanolamine (MEA) can be detected in the regeneration recovery liquid (tetramethylammonium salt solution) obtained by regeneration in an acidic solution, and the nitrogen-containing compounds in the tetramethylammonium salt solution are not actually removed.

Concentration of each compound in waste developer solution (ppm) Removal rate (%) Concentration in tetramethylammonium salt solution NH ₄ ⁺ MEA TMA ⁺ NH ₄ ⁺ MEA NH ₄ ⁺ MEA TMA ⁺ 10 118 4166 40 43 56ppm 565ppm 9.7% Table (IV) High concentration of tetramethylammonium ion and monoethanolamine developer wastewater, no speed-up for adsorption operation

From the data of the first to third experiments, it can be seen that regardless of the concentration of tetramethylammonium ions in the developer waste solution, the ammonium ions and monoethanolamine can be effectively removed by the operation combination of high pH and high flow rate. Compared with the fourth experiment, it can be understood that the operation combination of increasing the operating pH and flow rate can not only effectively remove the ammonium ions and monoethanolamine in the regeneration recovery solution to reduce the burden of the back-end process, but also does not affect the total amount of the regeneration recovery solution (recovered tetramethylammonium salt solution) obtained by regenerating the acidic solution.

In addition, when the first ion resin 321 is saturated, the tetramethylammonium ions in the developer waste liquid can exchange with the nitrogen-containing compounds in the first ion resin 321 by using the developer waste liquid under high pH (acidity and alkalinity) conditions. The first filtered liquid discharged from the first ion resin 321 will contain a high concentration of tetramethylammonium ions. If the first filtered liquid is not subjected to adsorption treatment, it will cause the problem of wastewater discharge. Therefore, the present invention establishes the second adsorption unit 33 after the first adsorption unit 32 for the second adsorption, and performs pre-regeneration with 1% sodium hydroxide concentration (the concentration range can be 0.1wt%~2wt%) to achieve the purpose of wastewater treatment and effective recovery of tetramethylammonium ions.

The second ion resin 331 receives the high nitrogen alkaline first filtered liquid discharged from the first ion resin 321. The concentration of each compound is shown in Table (V) below. When the outlet pH of the second ion resin 331 is greater than 7, the valve is turned to the spare tower of the second ion resin 331 to continue adsorption. Then, the saturated second ion resin 331 is pre-regenerated with 1% sodium hydroxide. During the pre-regeneration, when the conductivity value of the outlet of the second ion resin 331 is less than 400us/cm, the waste liquid containing nitrogen-containing compounds can be discharged to the wastewater treatment plant for disposal. However, when the conductivity value of the outlet of the second ion resin 331 is equal to or greater than 400us/cm, the outlet must be switched to the container 311 so that the sodium ions in the alkaline solution are exchanged with the tetramethylammonium ions in the second ion resin 331 and become a solution containing tetramethylammonium hydroxide. When a fixed amount of 1% sodium hydroxide (NaOH) is injected into the second ion resin 331, the pre-regeneration is stopped immediately. Finally, the second ion resin 331 is used for standby after the sodium ions are desorbed with an acidic solution.

In a fifth experiment, the compound adsorbed by the second ion resin 331 is the waste liquid with high concentration of tetramethylammonium ions discharged from the first ion resin 321. When the outlet pH of the second ion resin 331 is greater than 7, the adsorption is stopped, and then the pre-regeneration is carried out with a flow rate of 1BV/hr of 1% sodium hydroxide and the waste liquid is discharged. The concentrations of ammonium ions, monoethanolamine and tetramethylammonium ions are analyzed by sampling, and the conductivity is also measured to determine the outlet waste water discharge mode (qualified waste liquid or recycled waste liquid). The analysis data are shown in Table (V), wherein the feed concentration is the concentration of the waste water entering the second ion resin 331. The qualified waste liquid is the composition of the discharge liquid when the conductivity value of the outlet of the second ion resin 331 is less than 400us/cm, and the recovered waste liquid is the composition of the discharge liquid when the conductivity value of the outlet of the second ion resin 331 is equal to or greater than 400us/cm. It can be understood from Table (V) that when the conductivity value of the outlet of the second ion resin 331 is less than 400us/cm, the sodium ions in the alkaline solution will only exchange ions with the nitrogen-containing compounds, and will not exchange ions with tetramethylammonium. Therefore, the nitrogen-containing compounds (NH ₄ ⁺ and MEA) components are higher and tetramethylammonium (TMA ⁺ ) components are lower, so qualified waste liquid can be directly discharged to the outside. When the conductivity value at the outlet of the second ion resin 331 is greater than or equal to 400us/cm, there are only a small amount of nitrogen-containing compounds in the second ion resin 331. Therefore, the alkaline solution can perform ion exchange with the tetramethylammonium in the second ion resin 331, resulting in a lower nitrogen-containing compound (NH ₄ ⁺ and MEA) component and a higher tetramethylammonium (TMA ⁺ ) component in the recovered waste liquid, thereby achieving the purpose of recovering tetramethylammonium hydroxide (TMAH).

Unit NH ₄ ⁺ MEA TMA ⁺ Feed concentration ppm 6 248 2318 Qualified waste liquid ppm 52 1287 ＜5ppm Recycling waste liquid ppm 15 493 4771 Table 5. Concentrations of various compounds in the ionic resin after adsorption of high concentration tetramethylammonium ion waste developer solution with alkaline solution

The experimental conditions of the sixth experiment are substantially the same as those of the fifth experiment, except that the sixth experiment only changes the concentration of tetramethylammonium ions in the feed of the second ion resin 331. Detailed data are shown in Table (VI).

Unit NH ₄ ⁺ MEA TMA ⁺ Feed concentration ppm 10 208 676 Qualified waste liquid ppm 245 3243 ＜5ppm Recycling waste liquid ppm 20 574 4694 Table 6. Concentrations of various compounds after adsorption of waste developer solution with low concentration of tetramethylammonium ions and regeneration with alkaline solution

From the experimental data in Table (V) and Table (VI), it can be known that the tetramethylammonium ion waste liquid discharged by the first ion resin 321 can be adsorbed by the second ion resin 331 to solve the problem of the highly alkaline and high-nitrogen waste water discharged by the first ion resin 321 to remove other nitrogen-containing compounds; when the second ion resin 331 is saturated, it can also be regenerated using alkaline solution to recover nearly 96% of tetramethylammonium ions.

From the above description, it can be seen that the method of recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in waste developer liquid of the present invention has the following effects:

1. Elimination of nitrogen-containing compounds: The present invention utilizes the characteristic that "the dissociation constant of nitrogen-containing compounds is much smaller than that of tetramethylammonium hydroxide". When the first ionic resin 321 is saturated, a high-acidity and alkaline developer waste liquid is used so that the tetramethylammonium hydroxide in the developer waste liquid can exchange the nitrogen-containing compounds in the first ionic resin 321, thereby reducing the nitrogen-containing compounds in the first ionic resin 321 and increasing the tetramethylammonium hydroxide in the first ionic resin 321.

2. Reduction of recycling costs: After the nitrogen-containing compounds in the first ionic resin 321 are removed, the ions adsorbed in the first ionic resin 321 are high-purity tetramethylammonium hydroxide. In the third control step 904, the first ionic resin 321 is regenerated using an acidic solution to remove the tetramethylammonium hydroxide in the first ionic resin 321 to obtain the tetramethylammonium salt solution. The tetramethylammonium salt solution that does not contain nitrogen-containing compounds can reduce the subsequent regeneration and recycling process, reduce the adverse interference effects of purification and electrodialysis, and has the effect of reducing recycling costs.

3. Reduction of resin and compliance with wastewater discharge regulations: The second adsorption unit 33 established after the first adsorption unit 32 can adsorb wastewater, and then use 1% sodium hydroxide to perform a pre-regeneration process to achieve the purpose of wastewater treatment and effective recovery of tetramethylammonium ions. The alkaline solution can perform ion exchange and remove nitrogen-containing compounds. When the conductivity of the discharged alkaline solution is less than 400us/cm, it meets the discharge standard and can be discharged into the wastewater treatment system. The acidic solution used in the regeneration process can then desorb tetramethylammonium hydroxide from the second ion resin 331 to regenerate and reduce the second ion resin 331.

4. Ability to release nitrogen-containing compounds in double reaction: In the first control step 902, the saturated first ion resin 321 is used to increase the pH of the first filter liquid to the first pH setting value, and the second flow rate in the first ion resin 321 is controlled to be 4BV/hr or greater than 4BV/hr, so that tetramethylammonium hydroxide in the developer waste liquid replaces the nitrogen-containing compounds in the first ion resin 321, thereby releasing the nitrogen-containing compounds in the first ion resin 321. , to release the nitrogen-containing compounds for the first time. In addition, in the ion exchange step 906, the sodium hydroxide in the alkaline solution can be used to first release the nitrogen-containing compounds in the second ion resin 331, and then release the tetramethylammonium ions in the second ion resin 331 to release the nitrogen-containing compounds for the second time, and make the alkaline solution discharged from the second ion resin 331 meet the discharge standards, thereby improving the recovery rate of tetramethylammonium hydroxide in wastewater.

In summary, the present invention can release the nitrogen-containing compounds in the first ion resin 321 after increasing the pH value of the developer waste liquid and increasing the flow rate of the developer waste liquid, so as to obtain a tetramethylammonium salt solution without nitrogen-containing compounds. The second ion resin 331 can adsorb the nitrogen-containing compounds and tetramethylammonium ions in the first filtered liquid, and perform a pre-regeneration process with an alkaline solution to first release the nitrogen compounds in the second ion resin 331 and then recover the tetramethylammonium hydroxide in the second ion resin 331. In addition, the nitrogen compounds discharged from the second ion resin 331 meet the discharge standard of waste liquid, so the purpose of the present invention can be achieved.

However, the above are only two preferred embodiments of the present invention, and should not be used to limit the scope of implementation of the present invention. In other words, any simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the content of the invention description are still within the scope of the present patent.

31: Circulation unit

311:Container

312: Circulation Pipeline

313: Water pump module

32: First adsorption unit

321:First Ion Resin

322: First pH sensing module

323: First conductivity sensing module

324: Second conductivity sensing module

325: First regeneration module

326: First valve module

33: Second adsorption unit

331: Second ion resin

332: Second pH sensing module

333: The third conductivity sensing module

334: Alkaline solution supply module

335: Second regeneration module

336: Second valve module

901: First adsorption step

902: First control step

903: Second control step

904: Third control step

905: Second adsorption step

906: Ion exchange step

907: Wastewater Discharge Steps

908: Wastewater recovery step

909: Resin regeneration step

FIG1 is a schematic diagram of a device, which is a first preferred embodiment of a device for recovering tetramethylammonium hydroxide in developer waste liquid and removing nitrogen-containing compounds of the present invention; FIG2 is a flow chart, which illustrates a method for recovering tetramethylammonium hydroxide in developer waste liquid and removing nitrogen-containing compounds corresponding to the device for recovering tetramethylammonium hydroxide in developer waste liquid and removing nitrogen-containing compounds in the first preferred embodiment; FIG3 is a schematic diagram of a device, which is a second preferred embodiment of a device for recovering tetramethylammonium hydroxide in developer waste liquid and removing nitrogen-containing compounds of the present invention; FIG4 is a flow chart illustrating a method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds from waste developer liquid corresponding to the device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds from waste developer liquid in the second preferred embodiment.

31: Circulation unit

311:Container

312: Circulation pipeline

313: Water pump module

32: First adsorption unit

321: First ion resin

322: The first pH sensing module

323: First conductivity sensing module

324: Second conductivity sensing module

325: First regeneration module

326: First valve module

33: Second adsorption unit

331: Second ion resin

332: Second pH sensing module

333: The third conductivity sensing module

334: Alkaline solution supply module

335: Second regeneration module

336: Second valve module

Claims (7)

A method for recovering tetramethylammonium hydroxide in developer waste liquid and removing nitrogen-containing compounds comprises the following steps: a first adsorption step, injecting a developer waste liquid in a container into a first ion resin at a first flow rate, the first ion resin adsorbing tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste liquid and flowing out a first filter liquid, the first ion resin being a cationic ion exchange resin tower; a first control step, when the acidity and alkalinity of the first filter liquid is greater than or equal to a first acidity and alkalinity setting value, increasing the flow rate of injecting the developer waste liquid into the first ion resin to a second flow rate, and controlling the flow rate of the developer waste liquid to a second flow rate by adjusting the pH of the first filter liquid to a second flow rate. Since the dissociation constant of the nitrogen-containing compound is less than that of tetramethylammonium hydroxide, the tetramethylammonium in the developer waste liquid exchanges the nitrogen-containing compound in the first ionic resin, thereby desorbing the nitrogen-containing compound in the first ionic resin, wherein the first acid-base setting value is 7; a second control step, when the conductivity of the developer waste liquid is similar to the conductivity of the first filter liquid, stop injecting the developer waste liquid into the first ionic resin; and a third control step, use an acidic solution on the first ionic resin to desorb the tetramethylammonium hydroxide in the first ionic resin to obtain a tetramethylammonium salt solution. A method for recovering tetramethylammonium hydroxide from waste developer liquid and removing nitrogen-containing compounds as described in claim 1, wherein in the first adsorption step, the first flow rate is 2BV/hr, and in the first control step, the second flow rate is greater than or equal to 4BV/hr. The method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid as described in claim 1 further comprises a second adsorption step after the first adsorption step. In the second adsorption step, when the conductivity of the developer waste liquid is different from the conductivity of the first filter liquid, the first filter liquid is injected into a second ion resin, and the second ion resin is a cationic ion exchange resin tower for adsorbing tetramethylammonium hydroxide and nitrogen-containing compounds in the first filter liquid, and a second filter liquid is discharged. The method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds from developer waste liquid as described in claim 3 further comprises an ion exchange step after the second adsorption step, and a resin regeneration step after the ion exchange step. In the ion exchange step, when the acidity and alkalinity of the second filter liquid is greater than or equal to a second acid-alkaline setting value, the injection of the first filter liquid into the second ion resin is stopped, and an alkaline solution is used for the second ion resin, wherein the second acid-alkaline setting value is 7, and the concentration of the alkaline solution is 0.1%-2%. In the resin regeneration step, the injection of the alkaline solution into the second ion resin is stopped, and an acidic solution is used for the second ion resin. The method for recovering tetramethylammonium hydroxide in developer waste liquid and removing nitrogen-containing compounds as described in claim 4 further comprises a waste liquid discharge step after the ion exchange step, and a waste liquid recovery step between the waste liquid discharge step and the resin regeneration step. In the waste liquid discharge step, when the conductivity of the alkaline solution flowing out of the second ion resin is less than a conductivity setting value, the second filtered liquid is discharged to the outside. In the waste liquid recovery step, when the conductivity of the alkaline solution flowing out of the second ion resin is equal to or greater than the conductivity setting value, the alkaline solution flowing out of the second ion resin is guided back to the container, wherein the conductivity setting value is 400us/cm. A device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid is applicable to the method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid as described in any one of claims 1 to 2, comprising: a circulation unit, including a container, and a water pump module connected to the container, the container is used to accommodate a developer waste liquid; and a first adsorption unit, including a first ion resin connected to the container, a first acidity sensing module arranged at the outlet of the first ion resin, a first conductivity sensing module arranged at the inlet of the first ion resin, a second conductivity sensing module arranged at the outlet of the first ion resin, a first regeneration module arranged at the inlet of the first ion resin, module, and a first valve module disposed at the outlet of the first ion resin; the water pump module is used to inject the developer waste liquid into the first ion resin, the first ion resin is a cationic ion exchange resin tower used to adsorb tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste liquid and flow out a first filter liquid, the first pH sensing module is used to detect the first The first conductivity sensing module is used to detect the conductivity of the first filter liquid flowing out of the ion resin, the second conductivity sensing module is used to detect the conductivity of the first filter liquid flowing out of the first ion resin, and the first regeneration module is used to inject an acidic solution into the first ion resin to desorb hydrogen inside the first ion resin. Tetramethylammonium oxide, the first valve module is used to control the liquid output by the first ion resin to be discharged outward or directed back to the container; when the water pump module is turned on to inject the developer waste liquid in the container into the first ion resin, the first regeneration module is closed to prohibit the acid solution from being injected into the first ion resin, and the detection value of the first pH sensing module is less than a first When the acid-base setting value is 7, the first valve module controls the first filter liquid output by the first ion resin to be discharged outward; when the detection value of the first acid-base sensing module is greater than or equal to the first acid-base setting value, and the detection value of the second conductivity sensing module is less than the detection value of the first conductivity sensing module, the water pump module is turned on. The first regeneration module is closed to prohibit the acid solution from being injected into the first ion resin, and the first valve module controls the first filtered liquid output from the first ion resin to be guided back to the container; when the detection value of the first acid-base sensing module is greater than or equal to the first acid-base setting value, and the first When the detection value of the second conductivity sensing module is substantially equal to the detection value of the first conductivity sensing module, the water pump module is closed to prohibit the developer waste liquid in the container from being injected into the first ion resin, the first regeneration module is opened to inject the acid solution into the first ion resin, and the first valve module controls the first filter liquid output by the first ion resin to be discharged outward. A device for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid is applicable to the method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds in developer waste liquid as described in any one of claims 1 to 5, comprising: a circulation unit, including a container, and a water pump module connected to the container, the container is used to accommodate a developer waste liquid; a first adsorption unit, including a first adsorption unit disposed in the first adsorption unit; A first ion resin at the outlet of the container, a first acidity sensing module disposed at the outlet of the first ion resin, a first conductivity sensing module disposed at the inlet of the first ion resin, a second conductivity sensing module disposed at the outlet of the first ion resin, a first regeneration module disposed at the inlet of the first ion resin, and a first regeneration module disposed at the outlet of the first ion resin. a valve module; and a second adsorption unit, comprising a second ion resin disposed between the first ion resin outlet and the container inlet, a second acidity and alkalinity sensing module disposed at the second ion resin outlet, a third conductivity sensing module disposed at the second ion resin outlet, an alkaline liquid supply module disposed at the second ion resin inlet, and a a second regeneration module, and a second valve module disposed at the outlet of the second ion resin; the water pump module is used to inject the developer waste liquid into the first ion resin, the first regeneration module is used to inject an acid solution into the first ion resin, the first ion resin is a cationic ion exchange resin tower used to adsorb tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste liquid, the first acidity and alkalinity sensing module The first conductivity sensing module is used to detect the acidity and alkalinity of the first filter liquid flowing out of the first ion resin, the first conductivity sensing module is used to detect the conductivity of the developer waste liquid flowing out of the container, the second conductivity sensing module is used to detect the conductivity of the first filter liquid flowing out of the first ion resin, and the first regeneration module is used to inject an acidic solution into the first ion resin to release tetrahydrofuran in the first ion resin. The first valve module is used to control the liquid output from the first ion resin to be discharged or injected into the second ion resin; the second ion resin is a cationic ion exchange resin tower used to adsorb tetramethylammonium and nitrogen-containing compounds in the first filter liquid discharged from the second ion resin, the second pH sensing module is used to detect the pH value of the second filter liquid discharged from the second ion resin, and the second The three conductivity sensing modules are used to detect the conductivity of the second filter liquid discharged from the second ion resin. The alkaline solution supply module is used to inject an alkaline solution into the second ion resin so that the ions in the alkaline solution can exchange ions with the nitrogen-containing compound or tetramethylammonium ions in the second ion resin. The second regeneration module is used to inject an acidic solution into the second ion resin to release the second ion resin. The second valve module is used to control the liquid output by the second ion resin to be discharged outward or directed back to the container; when the water pump module is turned on to inject the waste developer liquid in the container into the first ion resin, the first regeneration module is turned off to prohibit the acid solution from being injected into the first ion resin, and the detection value of the first acid-base sensing module is less than a first acid-base setting value, the The first valve module controls the first filter liquid output by the first ion resin to be discharged outward, and the first acid-base setting value is 7; when the detection value of the first acid-base sensing module is greater than or equal to the first acid-base setting value, and the detection value of the second conductivity sensing module is less than the detection value of the first conductivity sensing module, the water pump module is turned on to inject the waste developer liquid in the container into the first ion resin. The first regeneration module is closed to prohibit the acid solution from being injected into the first ionic resin, and the first valve module controls the first filter liquid output by the first ionic resin to be introduced into the second ionic resin; when the detection value of the first acid-base sensing module is greater than or equal to the first acid-base setting value, and the detection value of the second conductivity sensing module is substantially equal to the detection value of the first conductivity sensing module, When measuring the value, the water pump module is closed to prohibit the developer waste liquid in the container from being injected into the first ion resin, the first regeneration module is opened to inject the acid solution into the first ion resin, and the first valve module controls the first filter liquid output from the first ion resin to be discharged outward; when the first valve module controls the first filter liquid output from the first ion resin to be introduced into the second ion resin, the first valve module is closed. When the alkaline solution supply module stops injecting alkaline solution into the second ion resin, the second regeneration module is closed to stop injecting acid solution into the second ion resin, and the detection value of the second acid-base sensing module is less than a second acid-base setting value, the second valve module controls the second ion resin output second filtered liquid to be discharged outward, and the second acid-base setting value is 7; when the second acid-base sensing module When the detection value of the first conductivity sensing module is greater than or equal to the second acid-base setting value, and the detection value of the third conductivity sensing module is less than a conductivity setting value, the first valve module stops inputting the first filter liquid output by the first ion resin into the second ion resin, opens the alkaline solution supply module to inject alkaline solution into the second ion resin, closes the second regeneration module to stop injecting acid into the second ion resin, and stops the second ion resin from being injected. The second valve module controls the second filter liquid output by the second ion resin to be discharged outwardly, and the conductivity setting value is 400us/cm; when the detection value of the second pH sensing module is greater than or equal to the second pH setting value, and the detection value of the third conductivity sensing module is greater than or equal to a conductivity setting value, the first valve module stops inputting the first filter liquid into the second ion resin. The first filtered liquid outputted from the ionic resin is turned on to inject the alkaline solution into the second ionic resin, the second regeneration module is turned off to stop injecting the acid solution into the second ionic resin, and the second valve module controls the second filtered liquid outputted from the second ionic resin to be recovered to the container to recover the tetramethylammonium hydroxide in the second ionic resin; when the second ionic resin is After the tetramethylammonium hydroxide is recovered, the first valve module stops inputting the first filtered liquid output by the first ionic resin into the second ionic resin, closes the alkaline solution supply module to stop injecting alkaline solution into the second ionic resin, opens the second regeneration module to inject acidic solution into the second ionic resin, and the second valve module controls the second filtered liquid output by the second ionic resin to be discharged outward.

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