Device and method for testing degradation and dissolution amount of ion exchange resin

Abstract

The invention discloses a device and a method for testing degradation and dissolution quantity of ion exchange resin, and relates to the field of performance testing of ion exchange resin. An inlet of a peristaltic pump is communicated with a liquid outlet of a liquid inlet box, an outlet of the peristaltic pump is communicated with an inlet of a temperature control heater, the upper end of an exchange column is communicated with an outlet of the temperature control heater, and the lower end of the exchange column is connected with a liquid storage box; the liquid storage tank is connected with the second gas collector, and the nitrogen cylinder gas conveying pipe penetrates into the liquid storage tank. Water washing or pretreatment is completed before testing, then heating temperature is set according to operation conditions, demineralized water or treating fluid is introduced into an exchange column, when gas-phase degradation products need to be collected, the gas-phase degradation products are collected through a first gas collector and a second gas collector, and if the sample is anion exchange resin, high-purity nitrogen is introduced into a liquid storage tank through a nitrogen cylinder, and the sample is collected through a second gas collector. The volatile organic matter is purged into a second gas collector, and finally the degradation and dissolution amount of the ion exchange resin is calculated according to TOC or chemical oxygen demand, the concentration of methanol and trimethylamine and the content of sulfate radicals or ammonia nitrogen.

Description

Technical Field

[0001] The invention relates to the field of ion exchange resin performance testing, and in particular to a device and method for testing the degradation and dissolution amount of ion exchange resin. Background Art

[0002] With the development of separation technology, the performance requirements for water treatment ion exchange resins are becoming increasingly higher. In addition to conventional physical and chemical properties such as exchange capacity, water content, and particle size, indicators such as temperature resistance and organic leachables of ion exchange resins are also receiving more and more attention.

[0003] In the condensate system of air-cooled units, water temperatures often exceed 65°C in summer. Using anion exchange resin with poor temperature tolerance can significantly degrade thermally. This not only reduces the exchange capacity of the ion exchange resin itself and reduces water production, but also pollutes the water treatment system with its thermal degradation products, threatening the safe operation of the unit. Furthermore, some ion exchange resin suppliers recycle used resin, reprocess it, and sell it as new resin. When these recycled resins are used in applications requiring high-quality treated water, abnormal effluent conductivity or elevated organic matter content can result, causing significant losses for users. Furthermore, many ion exchange resin applications, such as sugar purification, high-purity water production, and drug screening, require specific temperature tolerance and dissolution capacity. Therefore, developing a comprehensive and reliable method for testing ion exchange resin degradation and dissolution capacity is crucial.

[0004] Currently available methods related to ion exchange resin degradation and leachable determination include the following. First, the method specified in Appendix C of DL / T 519-2014, "Acceptance Standard for Ion Exchange Resins for Power Plant Water Treatment," is used to soak a certain volume of ion exchange resin at a constant temperature of 60°C for 16 hours, measure the total organic carbon (TOC) content of the soaking liquid, and calculate the total organic carbon content dissolved per unit volume of resin. However, this method is only suitable for new cation exchange resins. Second, the method specified in DL / T 1077-2018, "Determination of Organic Dissolved Matter from Ion Exchange Resins," is used. However, this method is only applicable to the determination of organic dissolved matter in granular new resins used for power plant water treatment. It includes dynamic and static methods. The dynamic method involves quantitatively loading pretreated resin into a dynamic circulation device. Under constant temperature and dynamic circulation conditions, a certain amount of pure water is continuously passed through the resin layer. The TOC content of the circulating liquid is regularly measured, and the level of resin dissolved matter is evaluated by the dissolution rate. The static method is similar to Appendix C of DL / T 519-2014, "Acceptance Standard for Ion Exchange Resins for Power Plant Water Treatment." Third, the application publication number is CN 118624551. A's invention patent discloses a test method for testing the dissolution characteristics of cation exchange resins. The method uses a leaching step to quickly remove residual organic matter in the resin and eliminate its interference with subsequent constant temperature dissolution results. 225 The test and the total organic carbon concentration test characterize the total dissolution level of the index resin; the fourth is the method disclosed in the invention patent "A rapid detection method for cation exchange resin dissolution" with application number CN202110058559, which determines the content of sulfate ions in the water sample containing cation exchange resin dissolution, and then irradiates the water sample with ultraviolet light, and then determines the content of sulfate ions after irradiation. The difference between the content of sulfate ions after irradiation and the content of sulfate ions before irradiation is the content of cation exchange resin dissolution.

[0005] The four currently available methods have the following limitations: First, methods 1 and 2, based on the measurement principle of a TOC analyzer, essentially measure the content of carbon-containing organic matter in the leachate that cannot be purged. However, during the degradation and dissolution process of ion exchange resins, not only are there small carbon-containing organic matter that did not react completely during the synthesis process, but also, according to the Hofmann reaction principle, there are volatile degradation products such as trimethylamine, methanol, and small ammonia molecules. The main trimethylamine and methanol cannot be characterized by measuring the TOC content of the liquid phase. Second, methods 3 and 4 only consider the degradation and dissolution of carbon-containing substances, ignoring non-carbon-containing substances such as ammonia nitrogen and sulfate. However, accumulated experience in the field of actual ion exchange resin testing has found that under high temperature, anion exchange resins decompose to produce small ammonia nitrogen molecules that dissolve in water, and cations degrade to produce sulfate molecules that dissolve in water. Third, the dynamic method of methods 2, 3, and 4 lacks high automation and adjustability, making it impossible to measure the degradation and dissolution of ion exchange resins under special operating conditions, such as setting a specific flow rate, temperature, and influent composition. Fourth, all current methods only consider the organic matter content in the liquid phase after dissolution of ion exchange resin, while a large amount of volatile degradation products exist in the gas phase and have not been tested and evaluated. Summary of the Invention

[0006] In response to the problems existing in the prior art, the present invention provides a device and method for testing the degradation and dissolution amount of ion exchange resin to solve the problems that the current method cannot measure volatile degradation products, does not contain carbon, does not consider special working conditions, and has low automation and adjustability. Different operating conditions can be set according to specific testing requirements. On the one hand, it can measure the dissolution and degradation products in the liquid phase and the degradation products in the gas phase. On the other hand, it takes into account volatile organic matter and carbon-free small molecule dissolution in the liquid phase. The degree of automation is high, the results are accurate and reliable, and more comprehensive and true.

[0007] The present invention is achieved through the following technical solutions: A device for testing the degradation and dissolution amount of ion exchange resin, comprising a peristaltic pump, a nitrogen bottle and vertically distributed exchange columns; The inlet of the peristaltic pump is connected to the liquid outlet of the liquid inlet box, the outlet of the peristaltic pump is connected to the inlet of the temperature-controlled heater, the exchange column is used to place the ion exchange resin to be tested, the upper end of the exchange column is connected to the outlet of the temperature-controlled heater, and the lower end of the exchange column is externally connected to the liquid storage tank; The upper end of the exchange column is externally connected to a first gas collector, the liquid storage tank is externally connected to a second gas collector, and the gas delivery pipe of the nitrogen bottle is deeply inserted into the liquid storage tank.

[0008] Preferably, the inlet of the peristaltic pump is connected to the liquid outlet of the liquid inlet tank through a first pipeline, the first pipeline is equipped with a liquid inlet valve, the lower end of the exchange column is connected to the liquid inlet of the liquid storage tank through a liquid guide tube, the liquid guide tube is equipped with a liquid outlet valve, and the bottom of the liquid storage tank is provided with a drain pipe, and the drain pipe is equipped with a drain valve; The upper end of the exchange column is connected to the inlet of the first gas collector through a first exhaust pipeline, and the liquid storage tank is connected to the inlet of the second gas collector through a second exhaust pipeline. A first gas phase outlet valve is installed on the first exhaust pipeline, and a second gas phase outlet valve is installed on the second exhaust pipeline.

[0009] Furthermore, the outlet of the temperature-controlled heater is connected to the upper end of the exchange column through a second pipeline. A thermometer is installed near the upper end of the exchange column on the second pipeline, and the thermometer is used to transmit a temperature signal to the temperature-controlled heater.

[0010] Furthermore, the upper end of the exchange column is externally connected to a third exhaust pipeline, the liquid storage tank is externally connected to a fourth exhaust pipeline, the third exhaust pipeline is installed with a first exhaust valve, and the fourth exhaust pipeline is installed with a second exhaust valve.

[0011] Furthermore, the first exhaust pipeline and the second exhaust pipeline are both L-shaped, the first gas collector and the second gas collector are both horizontally distributed, the outlet of the horizontal section of the first exhaust pipeline is connected to the inlet of the first gas collector, and the outlet of the horizontal section of the second exhaust pipeline is connected to the inlet of the second gas collector.

[0012] Furthermore, the first gas collector and the second gas collector are both transparent or translucent cylindrical and marked with volume scales, and the outer sides of the first gas collector and the second gas collector are open; The first gas collector is equipped with a first piston that slides with its own inner wall, and the second gas collector is equipped with a second piston that slides with its own inner wall. A first push rod is fixed to the outer end of the first piston, and a second push rod is fixed to the outer end of the second piston. The liquid storage tank is transparent or translucent and is marked with a volume scale.

[0013] Furthermore, a bottom plate is provided near the bottom of the exchange column. The bottom plate is a sand core or a filter plate with a plurality of through holes evenly arranged. The inner diameter of the through holes is smaller than the volume of the ion exchange resin particles to be tested.

[0014] A method for testing the degradation and dissolution amount of an ion exchange resin, based on the device for testing the degradation and dissolution amount of an ion exchange resin as described above, comprises the following steps: S1, within the set time, the deionized water or pretreatment solution in the liquid inlet tank is passed into the exchange column through the peristaltic pump, and then the effluent flows into the liquid storage tank, completing the water washing or pretreatment process of the ion exchange resin to be tested; S2, according to the working conditions of the ion exchange resin to be tested during actual operation, set the temperature of the temperature control heater, and as needed, pass the deionized water or treatment solution in the liquid inlet tank into the exchange column through a peristaltic pump, and then the effluent Q flows into the liquid storage tank. If it is necessary to collect the gaseous degradation products in the ion exchange resin to be tested, the first gas collector and the second gas collector are used to collect them. If the ion exchange resin to be tested is an anion exchange resin, high-purity nitrogen is introduced from a nitrogen bottle to the liquid level of the liquid storage tank through a gas pipe, and volatile organic compounds are purged into the second gas collector by bubbling; S3, determine the TOC content or chemical oxygen demand in the effluent Q, as well as the methanol and trimethylamine concentrations in the first gas collector and the second gas collector. If the ion exchange resin to be tested is a cation exchange resin, determine the sulfate content of the effluent Q. If the ion exchange resin to be tested is an anion exchange resin, determine the ammonia nitrogen content in the effluent Q. Calculate the degradation of the ion exchange resin to be tested and the total organic carbon content or organic oxygen demand, ammonia nitrogen or sulfate content, methanol and trimethylamine content of the dissolved matter, and complete the test of ion exchange resin degradation and dissolution amount.

[0015] Furthermore, the flow rate range of the peristaltic pumps in S1 and S2 is 20 mL / min~200 mL / min.

[0016] Furthermore, the degradation of the ion exchange resin and the total organic carbon content of the dissolved matter in S3 were analyzed. R a or organic oxygen demand R b , ammonia nitrogen or sulfate content R c , methanol R d and trimethylamine R e The contents were obtained according to the following formula: or ; or ; or ; or ; or ; in: C TOC —TOC content in the effluent Q, in mg / L; V L—The volume of the effluent Q, in L; M —The mass of the ion exchange resin to be tested, in kg; C COD —chemical oxygen demand in the effluent Q, in mg / L; C N(S) — C N or C S , C N is the ammonia nitrogen content in the effluent Q, C S is the sulfate content in the effluent Q, in mg / L; C 甲醇 —Methanol concentration, in mg / L; V Q —The total volume of gas in the first gas collector and the second gas collector, in L; C 三甲胺 —Concentration of trimethylamine, in mg / L; V —The volume of the ion exchange resin to be tested, in L; R a 、 R b 、 R c 、 R d and R e The unit is mg / kg 湿树脂 or mg / L 湿树脂 .

[0017] Compared with the prior art, the present invention has the following beneficial technical effects: The invention discloses a device for testing the degradation and dissolution amount of an ion exchange resin. The device comprises the following steps: a peristaltic pump is used to pass deionized water or a pretreatment solution in a liquid inlet box into an exchange column, and then an effluent flows into a liquid storage tank, thereby completing water washing or pretreatment of the resin; a temperature-controlled heater is used to set a temperature according to actual operating conditions of the resin; the heated deionized water or treatment solution is passed into the exchange column and then flows into the liquid storage tank; and first and second gas collectors are used to collect gaseous degradation products in the resin; and when the resin is an anion exchange resin, a nitrogen bottle is used to pass high-purity nitrogen to the liquid surface of the liquid storage tank through a gas pipe, and volatile organic matter is purged into the second gas collector by bubbling, thereby facilitating the measurement of the TOC content or chemical oxygen demand in the effluent, the methanol and trimethylamine concentrations in the first and second gas collectors, the sulfate content of the effluent in the case of a cation exchange resin, and the ammonia nitrogen content in the case of an anion exchange resin, thereby facilitating the final calculation of the degradation of the resin and the total organic carbon content or organic oxygen demand, ammonia nitrogen or sulfate content, and the methanol and trimethylamine content of the dissolution products. The device of the present invention can automatically process ion exchange resin samples according to different conditions, such as high temperature and oxidizing components in the influent water, collect the effluent, and conduct comprehensive testing on the liquid and gas phase degradation and dissolution of the ion exchange resin during operation. In addition, according to the degradation law of the ion exchange resin, on the one hand, the degradation products in the gas phase can be collected. On the other hand, considering that the volatile organic matter in the liquid phase cannot be measured during the total organic carbon test, the gas pipe of the nitrogen bottle is deeply inserted into the liquid storage tank, and the volatile organic matter is directly purged into the second gas collector by bubbling and purging with high-purity nitrogen, which is convenient for later testing.

[0018] The present invention provides a method for testing the degradation and dissolution amount of an ion exchange resin. The method comprises the following steps: first, deionized water or a pretreatment solution in a liquid inlet tank is passed into an exchange column through a peristaltic pump to complete a water washing or pretreatment process of the resin; then, a heating temperature is set according to actual operating conditions, and the deionized water or the treatment solution is passed into the exchange column through the peristaltic pump; if gaseous degradation products need to be collected, they are collected using first and second gas collectors; if the resin is an anion exchange resin, high-purity nitrogen is passed from a nitrogen bottle to the liquid surface of the liquid storage tank through a gas transmission pipe, and volatile organic matter is purged into the second gas collector by bubbling; the TOC content or chemical oxygen demand in the effluent, as well as the methanol and trimethylamine concentrations in the first and second gas collectors are measured; the sulfate content of the effluent is measured using a cation exchange resin, and the ammonia nitrogen content is measured using an anion exchange resin; the degradation of the resin and the total organic carbon content or organic oxygen demand, the ammonia nitrogen or sulfate content, and the methanol and trimethylamine content of the dissolution can be calculated, so that the degradation and dissolution amount of the ion exchange resin sample under different units and standards under the set operating conditions can be obtained. The present invention breaks through the limitation of traditional methods that only consider non-volatile organic degradation and dissolution. It simultaneously measures the degradation products in the gas phase according to the degradation laws of anion and cation exchange resins, taking into account both carbon-containing organic matter in the degradation and dissolution processes and volatile organic matter and carbon-free small molecule dissolutions (ammonia nitrogen, sulfate). It has a high degree of automation and produces accurate and reliable results. It can comprehensively test and analyze the degradation and dissolution amount of ion exchange resins under set working conditions. It is of great significance for the production, research and development, application, acceptance, adjustment and optimization of operating processes, and diagnosis of abnormal operating conditions of ion exchange resins. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of a device for testing the degradation and dissolution amount of ion exchange resin according to the present invention.

[0020] In the figure: liquid inlet tank 1, liquid inlet valve 2, peristaltic pump 3, temperature control heater 4, first push rod 51, second push rod 52, filter plate 6, thermometer 7, exchange column 8, first gas phase outlet valve 9, first gas collector 10, first drain valve 11, liquid outlet valve 12, liquid storage tank 13, nitrogen bottle 14, second gas phase outlet valve 15, second gas collector 16, second drain valve 17, drain valve 18. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments and drawings, which are intended to explain rather than limit the present invention.

[0022] like Figure 1 As shown in FIG, a device for testing the degradation and dissolution amount of ion exchange resin according to the present invention is shown. Figure 1As shown, it mainly includes a liquid inlet box 1, a liquid inlet valve 2, a peristaltic pump 3, a temperature-controlled heater 4, a thermometer 7, a vertically distributed exchange column 8, a liquid outlet valve 12, a liquid storage tank 13, a nitrogen bottle 14 and a drain valve 18.

[0023] The inlet of the peristaltic pump 3 is connected to the outlet of the liquid inlet tank 1 via a first pipeline, which is equipped with a liquid inlet valve 2. The liquid inlet tank 1 is filled with deionized water. If the degradation of the ion exchange resin under specific operating conditions needs to be measured, a corresponding reagent can be added to the deionized water to form a corresponding treatment solution. The peristaltic pump 3 can adjust the flow rate of the liquid. The outlet of the peristaltic pump 3 is connected to the inlet of the temperature-controlled heater 4 via a liquid pipeline. The temperature-controlled heater 4 can heat the liquid flowing through it and the temperature is adjustable. The ion exchange resin sample to be tested is placed in the exchange column 8. The upper end of the exchange column 8 is connected to the outlet of the temperature-controlled heater 4, and the outlet of the lower end of the exchange column 8 is connected to the inlet of the liquid storage tank 13 via a liquid conduit. The liquid conduit is equipped with a liquid outlet valve 12, which transports the liquid flowing through the ion exchange resin layer into the liquid storage tank 13. A drain pipe is provided at the bottom of the liquid storage tank 13, and a drain valve 18 is installed on the drain pipe. The liquid storage tank 13 is transparent or translucent and marked with a volume scale.

[0024] In the present invention, the exchange column 8 is provided with a base plate near the bottom. This base plate is a sand core or a filter plate 6 with a plurality of evenly spaced through holes. The inner diameter of the through holes is smaller than the volume of the ion exchange resin particles, preventing leakage of the ion exchange resin sample. The peristaltic pump 3 has a controllable flow rate range of 20 mL / min to 200 mL / min. The temperature-controlled heater 4 has an adjustable temperature range of 30°C to 95°C, with a temperature control accuracy better than ±1.5°C.

[0025] The top of the exchange column 8 is connected to the inlet of the first gas collector 10 via a first exhaust line, and the upper portion of the liquid storage tank 13 is connected to the inlet of the second gas collector 16 via a second exhaust line. A first gas phase outlet valve 9 is installed on the first exhaust line, and a second gas phase outlet valve 15 is installed on the second exhaust line. The nitrogen cylinder 14 is equipped with a gas valve and a pressure reducing valve, and its gas supply pipe is inserted below the liquid level of the liquid storage tank 13. Specifically, the first and second exhaust lines are both L-shaped, and the first and second gas collectors 10 and 16 are both horizontally distributed and transparent or translucent cylindrical, with volume scales marked on them. The outlet of the horizontal section of the first exhaust line is connected to the inlet of the first gas collector 10, and the outlet of the horizontal section of the second exhaust line is connected to the inlet of the second gas collector 16. The outer sides of the first gas collector 10 and the second gas collector 16 are opened. A first piston sliding with its own inner wall is installed in the first gas collector 10, and a second piston sliding with its own inner wall is installed in the second gas collector 16. A first push rod 51 is fixed to the outer end of the first piston, and a second push rod 52 is fixed to the outer end of the second piston.

[0026] Furthermore, the outlet of temperature-controlled heater 4 is connected to the upper inlet of exchange column 8 via a second pipeline. A thermometer 7 is installed in this second pipeline near the upper end of exchange column 8. Thermometer 7 transmits a temperature signal to temperature-controlled heater 4, allowing temperature-controlled heater 4 to adjust the liquid temperature to an appropriate value when the set temperature is not reached or exceeded. A third exhaust pipeline is also externally connected to the upper end of exchange column 8, with a first drain valve 11 installed on the third exhaust pipeline. A fourth exhaust pipeline is also externally connected to liquid storage tank 13, with a second drain valve 17 installed on the fourth exhaust pipeline.

[0027] When it is necessary to measure the volatile organic matter in the ion exchange resin eluate, the nitrogen bottle 14 can be opened to bubble nitrogen into the effluent of the ion exchange resin to purge the volatile organic matter into the gas phase of the liquid storage tank 13, and the gas to be measured is collected by the second gas collector 16. The lower part of the liquid storage tank 13 is connected to a water outlet, and the effluent can be discharged or collected for measurement through the drain pipe and drain valve 18.

[0028] The present invention provides a method for testing the degradation and dissolution amount of ion exchange resin, based on the above-mentioned device, comprising the following steps: The first step is to add deionized water or pretreatment solution into the liquid inlet tank 1, and use a balance to weigh a certain mass of the ion exchange resin sample to be tested after removing free water, which is recorded as M , or use a measuring cylinder to measure a certain volume of the ion exchange resin sample to be tested, recorded as V , transfer it to the exchange column 8 using deionized water, discharge the bubbles in the resin layer, and keep the liquid level height of 3cm~8cm above the ion exchange resin layer; In the second step, the various pipelines and components of the device are connected, the liquid inlet valve 2, the peristaltic pump 3, the first drain valve 11, the liquid outlet valve 12, the second drain valve 17, and the drain valve 18 are opened, the first gas phase outlet valve 9, the pressure reducing valve and the gas valve of the nitrogen bottle 14, and the second gas phase outlet valve 15 are closed, and deionized water or a pretreatment solution is passed into the exchange column 8, maintaining a certain flow rate and time. After that, the effluent flows into the liquid storage tank 13 and then flows out through the drain valve 18, completing the washing or pretreatment process of the ion exchange resin sample to be tested; The third step is to set the temperature of the temperature-controlled heater 4 according to the different operating conditions during the actual operation of the ion exchange resin. If it is necessary to test the oxidative degradation of the ion exchange resin, the required amount of oxidant, such as sodium hypochlorite or hydrogen peroxide, can be added to the deionized water to form a corresponding treatment solution. The deionized water or treatment solution at a certain temperature is passed into the exchange column 8, and the flow rate is controlled by the peristaltic pump 3; The 4th step, when needing to start collecting ion exchange resin degradation and dissolution, opens the first gas phase outlet valve 9 and the second gas phase outlet valve 15, closes the first drain valve 11, the second drain valve 17 and the drain valve 18, collects the gas phase degradation product in batches with the first gas collector 10 and the second gas collector 16, collects the ion exchange resin sample effluent in the exchange column 8 with liquid storage tank 13; In the fifth step, if the sample is an anion exchange resin and the TOC content of the liquid phase is to be determined, the pressure reducing valve of the nitrogen cylinder 14 is opened, and high-purity nitrogen is introduced into the liquid storage tank 13 below the liquid level. The volatile organic compounds in the effluent of the ion exchange resin sample are purged into the gas phase by bubbling and collected by the second gas collector 16; Step 6: Record the volume of liquid in the liquid storage tank 13 as V L , the total volume of gas in the first gas collector 10 and the second gas collector 16 is recorded by the positions of the first piston and the second piston. V Q , open the drain valve 18 and transfer the ion exchange resin sample outflow in the liquid storage tank 13 into the plastic bottle for testing; The seventh step is to measure the TOC content by using a total organic carbon analyzer, which is recorded as C TOC , or measure chemical oxygen demand (COD) by potassium dichromate oxidation method Cr , recorded as C COD If the sample is a cation exchange resin, determine the sulfate content of the liquid in the plastic bottle in step 6 by ion chromatography or turbidimetry. C S If the sample is an anion exchange resin, determine the ammonia nitrogen content of the liquid in the plastic bottle in step 6 using Nessler's reagent spectrophotometry. C N The gas samples in the first gas collector 10 and the second gas collector 16 are passed into a gas chromatograph to measure the concentrations of methanol and trimethylamine, which are recorded as C 甲醇 and C 三甲胺 ; Step 8: After sampling is completed, open the first drain valve 11 and the second drain valve 17 to drain the gas in the entire pipeline, and open the drain valve 18 to drain the liquid in the liquid storage tank 13 to facilitate the next operation; In the ninth step, the test can be repeated multiple times, and the gas phase and liquid phase degradation and dissolution products can be collected again, and steps 4 to 8 can be repeated; Step 10: Calculate the degradation and dissolution amount of ion exchange resin per unit mass according to formula (1) to formula (5) or calculate the degradation and dissolution amount of ion exchange resin per unit volume according to formula (6) to formula (10): (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) in: R 1—Degradation of ion exchange resin and total organic carbon content of leachables, in mg / kg 湿树脂 ; C TOC —TOC content of water from plastic bottles, in mg / L; V L —The volume of liquid in step 6 is in L; M —The mass of the ion exchange resin sample, in kg; R 2—Degradation of ion exchange resin and organic oxygen consumption of dissolved matter, in mg / kg 湿树脂 ; C COD —Chemical oxygen demand (COD) of water from plastic bottles Cr , unit is mg / L; R 3—Degradation of ion exchange resin and ammonia nitrogen (or sulfate) content of dissolved substances, in mg / kg 湿树脂 ; C N(S) —The ammonia nitrogen or sulfate content of the water discharged from the plastic bottle, in mg / L; R 4—Degradation of ion exchange resin and methanol content of dissolved substances, in mg / kg 湿树脂 ; C 甲醇 —Methanol content in the gas phase, in mg / L; V Q —Gas volume in step 6, in L; R5—Degradation of ion exchange resin and content of trimethylamine in dissolved substances, in mg / kg 湿树脂 ; C 三甲胺 —Trimethylamine content in the gas phase, in mg / L; R 6—Degradation of ion exchange resin and total organic carbon content of leachables, in mg / L 湿树脂 ; V —The volume of the ion exchange resin sample, in L; R 7—Degradation of ion exchange resin and organic oxygen consumption of dissolved matter, in mg / L 湿树脂 ; R 8—Degradation of ion exchange resin and ammonia nitrogen content of dissolved substances, in mg / L 湿树脂 ; R 9—Degradation of ion exchange resin and methanol content of leachate, in mg / L 湿树脂 ; R 10 —Degradation of ion exchange resin and trimethylamine content in dissolved substances, in mg / L 湿树脂 .

[0029] Step 11: According to the specific ion exchange resin sample and the corresponding working conditions, the test results R 1 or R 2 and R 3~ R Sum the corresponding results in 5, or R 6 or R 7 and R 8~ R 10 By summing the corresponding results in , we can obtain the degradation and dissolution amount of the ion exchange resin sample under different units and standards under the set working conditions.

[0030] Example 1 The present invention provides a method for testing the degradation and dissolution amount of an ion exchange resin, which specifically comprises the following steps: In the first step, deionized water is added to the liquid inlet tank 1, and 200 g of the anion exchange resin sample to be tested after free water is removed is weighed on a balance. The resin mass is recorded as M , transfer it to the exchange column 8, discharge the bubbles in the resin layer, and keep the liquid level at 8 cm above the ion exchange resin layer; The second step is to connect the various pipes and components of the device, open the liquid inlet valve 2, peristaltic pump 3, first drain valve 11, liquid outlet valve 12, second drain valve 17, and drain valve 18, close the first gas phase outlet valve 9, the pressure reducing valve and gas valve of the nitrogen bottle 14, and the second gas phase outlet valve 15, and pass deionized water into the exchange column 8, maintaining a constant flow rate of 100 mL / min for 30 minutes. After that, the effluent flows into the liquid storage tank 13 and then flows out through the drain valve 18, completing the water washing process of the ion exchange resin sample to be tested; Step 3: Set the temperature of the temperature-controlled heater 4 to 80°C, set the flow rate of the peristaltic pump 3 to 20 mL / min, and introduce 80°C deionized water into the exchange column 8; The 4th step, when beginning to collect ion exchange resin degradation and dissolution, opens the first gas phase outlet valve 9 and the second gas phase outlet valve 15, closes the first drain valve 11, the second drain valve 17 and the drain valve 18, collects the gas phase degradation product with the first gas collector 10 and the second gas collector 16, collects the ion exchange resin sample effluent in the exchange column 8 with liquid storage tank 13; Step 5: Open the pressure reducing valve of the nitrogen bottle 14 and introduce high-purity nitrogen into the liquid level of the liquid storage tank 13 to purge the volatile organic matter in the effluent of the ion exchange resin sample into the gas phase by bubbling, and collect it through the second gas collector 16; Step 6: Record the volume of liquid in the liquid storage tank 13 as V L , the total volume of gas in the first gas collector 10 and the second gas collector 16 is recorded by the positions of the first piston and the second piston. V Q , open the drain valve 18 and transfer the ion exchange resin sample outflow in the liquid storage tank 13 into the plastic bottle for testing; Step 7: Determine the chemical oxygen demand (COD) of the liquid in the plastic bottle in step 6 by potassium dichromate oxidation method. Cr , recorded as C COD , determine the ammonia nitrogen content by Nessler's reagent spectrophotometry C N The gas samples in the first gas collector 10 and the second gas collector 16 are passed into a gas chromatograph to measure the concentrations of methanol and trimethylamine, which are recorded as C 甲醇 and C 三甲胺 ; Step 8: After sampling is completed, open the first drain valve 11 and the second drain valve 17 to drain the gas in the entire pipeline, and open the drain valve 18 to drain the liquid in the liquid storage tank 13; The ninth step is to calculate the degradation and dissolution amount of ion exchange resin per unit mass according to formula (2) to formula (5): (2) (3) (4) (5) in: R 2—Degradation of ion exchange resin and organic oxygen consumption of dissolved matter, in mg / kg 湿树脂 ; C COD —Chemical oxygen demand (COD) of effluent Cr , unit is mg / L; V L —The volume of liquid in step 6 is in L; M —The mass of the ion exchange resin sample, in kg; R 3—Degradation of ion exchange resin and ammonia nitrogen content of dissolved substances, in mg / kg 湿树脂 ; C N —Ammonia nitrogen content of effluent, in mg / L; R 4—Degradation of ion exchange resin and methanol content of dissolved substances, in mg / kg 湿树脂 ; C 甲醇 —Methanol content in the gas phase, in mg / L; V Q —Gas volume in step 6, in L; R 5—Degradation of ion exchange resin and content of trimethylamine in dissolved substances, in mg / kg 湿树脂 ; C 三甲胺 —Trimethylamine content in the gas phase, in mg / L; Calculation results: R 2 = 110.2 mg / kg 湿树脂 , R 3 = 24.2 mg / kg 湿树脂 , R 4 = 46.8 mg / kg 湿树脂 , R 5 = 5.2 mg / kg 湿树脂 ; Step 10: ObtainR 2. R 3. R 4. R 5, we can get the degradation and dissolution amount of the ion exchange resin sample at 80℃.

[0031] Example 2 The present invention provides a method for testing the degradation and dissolution amount of an ion exchange resin, which specifically comprises the following steps: In the first step, deionized water is added to the liquid inlet tank 1, and 200 mL of the cation exchange resin sample to be tested is measured with a graduated cylinder. The resin volume is recorded as V , transfer it to the exchange column 8, discharge the bubbles in the resin layer, and keep the liquid level above the ion exchange resin layer at 5 cm; The second step is to connect the various pipes and components of the device, open the liquid inlet valve 2, peristaltic pump 3, first drain valve 11, liquid outlet valve 12, second drain valve 17, and drain valve 18, close the first gas phase outlet valve 9, the pressure reducing valve and gas valve of the nitrogen bottle 14, and the second gas phase outlet valve 15, and pass deionized water into the exchange column 8, maintaining a constant flow rate of 80 mL / min for 20 minutes. After that, the effluent flows into the liquid storage tank 13 and then flows out through the drain valve 18, completing the water washing process of the ion exchange resin sample to be tested; Step 3: Set the temperature of the temperature-controlled heater 4 to 60°C, set the flow rate of the peristaltic pump 3 to 25 mL / min, add hydrogen peroxide to the liquid inlet tank 1 to make a 1‰ hydrogen peroxide solution by volume, and start to pass the 60°C 1‰ hydrogen peroxide solution into the exchange column 8; In the fourth step, when the degradation of the ion exchange resin and the dissolution products are collected, the outlet valve 12 is opened and the ion exchange resin sample effluent in the exchange column 8 is collected by the liquid storage tank 13; Step 5: Record the volume of liquid in the liquid storage tank 13. V L , open the drain valve 18 and connect the ion exchange resin sample outflow in the liquid storage tank to the plastic bottle for testing, and measure the TOC content by the total organic carbon analyzer, which is recorded as C TOC , sulfate content was determined by ion chromatography C S ; Step 6: After sampling is completed, open the drain valve 18 to drain the liquid in the liquid storage tank 13; Step 7: Repeat the test multiple times, collect the liquid phase degradation and dissolution again, and repeat steps 4 to 6; Step 8: Calculate the degradation and dissolution amount of cation exchange resin per unit volume under 60°C oxidation conditions according to equations (6) and (8): (6) (8) in: R 6—Degradation of ion exchange resin and total organic carbon content of leachables, in mg / L 湿树脂 ; C TOC —TOC content of effluent, in mg / L; V —The volume of the ion exchange resin sample, in L; R 8—Degradation of ion exchange resin and ammonia nitrogen content of dissolved substances, in mg / L 湿树脂 ; C S —Sulfate content of effluent, in mg / L; Calculation results: R 6=150.0 mg / L 湿树脂 , R 8=64.8 mg / L 湿树脂 ; Step 10: Obtain R 6 and R The degradation and dissolution amount of the cation exchange resin sample under the oxidation condition of 60℃ can be obtained by summing the values of 8.

Claims

1. A device for testing the degradation and dissolution of ion exchange resin, characterized in that: It includes a peristaltic pump (3), a nitrogen bottle (14) and a vertically distributed exchange column (8); The inlet of the peristaltic pump (3) is connected to the liquid outlet of the liquid inlet box (1), and the outlet of the peristaltic pump (3) is connected to the inlet of the temperature-controlled heater (4). The exchange column (8) is used to place the ion exchange resin to be tested. The upper end of the exchange column (8) is connected to the outlet of the temperature-controlled heater (4), and the lower end of the exchange column (8) is externally connected to the liquid storage box (13); The upper end of the exchange column (8) is externally connected to a first gas collector (10), the liquid storage tank (13) is externally connected to a second gas collector (16), and the gas delivery pipe of the nitrogen bottle (14) is deeply inserted into the liquid storage tank (13).

2. The device for testing the degradation and dissolution amount of ion exchange resin according to claim 1, characterized in that: The inlet of the peristaltic pump (3) is connected to the liquid outlet of the liquid inlet box (1) through a first pipeline, and a liquid inlet valve (2) is installed on the first pipeline. The lower end of the exchange column (8) is connected to the liquid inlet of the liquid storage box (13) through a liquid guide tube, and a liquid outlet valve (12) is installed on the liquid guide tube. A liquid discharge pipe is provided at the bottom of the liquid storage box (13), and a liquid discharge valve (18) is installed on the liquid discharge pipe. The upper end of the exchange column (8) is connected to the inlet of the first gas collector (10) through a first exhaust pipeline, and the liquid storage tank (13) is connected to the inlet of the second gas collector (16) through a second exhaust pipeline. A first gas phase outlet valve (9) is installed on the first exhaust pipeline, and a second gas phase outlet valve (15) is installed on the second exhaust pipeline.

3. The device for testing the degradation and dissolution amount of ion exchange resin according to claim 2, characterized in that: The outlet of the temperature-controlled heater (4) is connected to the upper end of the exchange column (8) through a second pipeline. A thermometer (7) is installed at a position of the second pipeline near the upper end of the exchange column (8). The thermometer (7) is used to transmit a temperature signal to the temperature-controlled heater (4).

4. The device for testing the degradation and dissolution amount of ion exchange resin according to claim 3, characterized in that: The upper end of the exchange column (8) is also externally connected to a third exhaust pipeline, and the liquid storage tank (13) is also externally connected to a fourth exhaust pipeline. A first exhaust valve (11) is installed on the third exhaust pipeline, and a second exhaust valve (17) is installed on the fourth exhaust pipeline.

5. The device for testing the degradation and dissolution amount of ion exchange resin according to claim 2, characterized in that: The first exhaust pipeline and the second exhaust pipeline are both L-shaped, the first gas collector (10) and the second gas collector (16) are both horizontally distributed, the outlet of the horizontal section of the first exhaust pipeline is connected to the inlet of the first gas collector (10), and the outlet of the horizontal section of the second exhaust pipeline is connected to the inlet of the second gas collector (16).

6. The device for testing the degradation and dissolution amount of ion exchange resin according to claim 5, characterized in that: The first gas collector (10) and the second gas collector (16) are both transparent or translucent cylindrical and marked with volume scales. The outer sides of the first gas collector (10) and the second gas collector (16) are open. The first gas collector (10) is provided with a first piston that is slidably mounted on its inner wall, and the second gas collector (16) is provided with a second piston that is slidably mounted on its inner wall. A first push rod (51) is fixed to the outer end of the first piston, and a second push rod (52) is fixed to the outer end of the second piston. The liquid storage tank (13) is transparent or translucent and is marked with a volume scale.

7. The device for testing the degradation and dissolution amount of ion exchange resin according to claim 1, characterized in that: The exchange column (8) is provided with a bottom plate near the bottom thereof, the bottom plate being a sand core or a filter plate (6) evenly arranged with a plurality of through holes, wherein the inner diameter of the through holes is smaller than the volume of the ion exchange resin particles to be tested.

8. A method for testing the degradation and dissolution of ion exchange resin, characterized in that: The device for testing the degradation and dissolution amount of ion exchange resin according to any one of claims 1 to 7 comprises the following steps: S1, within a set time, the deionized water or pretreatment solution in the liquid inlet tank (1) is passed into the exchange column (8) through the peristaltic pump (3), and then the outflow liquid flows into the liquid storage tank (13), completing the water washing or pretreatment process of the ion exchange resin to be tested; S2, according to the actual operating conditions of the ion exchange resin to be tested, the temperature of the temperature control heater (4) is set, and as needed, the deionized water or the treatment solution in the liquid inlet tank (1) is passed into the exchange column (8) through the peristaltic pump (3), and then the effluent Q flows into the liquid storage tank (13). If it is necessary to collect the gaseous degradation products in the ion exchange resin to be tested, the first gas collector (10) and the second gas collector (16) are used to collect them in turn; If the ion exchange resin to be tested is an anion exchange resin, high-purity nitrogen is introduced from the nitrogen bottle (14) to the liquid level of the liquid storage tank (13) through the gas pipe, and volatile organic matter is purged into the second gas collector (16) by bubbling; S3, determine the TOC content or chemical oxygen demand in the effluent Q, as well as the methanol and trimethylamine concentrations in the first gas collector (10) and the second gas collector (16). If the ion exchange resin to be tested is a cation exchange resin, determine the sulfate content in the effluent Q. If the ion exchange resin to be tested is an anion exchange resin, determine the ammonia nitrogen content in the effluent Q. Calculate the degradation of the ion exchange resin to be tested and the total organic carbon content or organic oxygen demand, ammonia nitrogen or sulfate content, methanol and trimethylamine content of the dissolved matter, and complete the test of ion exchange resin degradation and dissolution amount.

9. The method for testing the degradation and dissolution amount of ion exchange resin according to claim 8, characterized in that: The flow rate range of the peristaltic pump (3) in S1 and S2 is 20 mL / min~200 mL / min.

10. The method for testing the degradation and dissolution amount of ion exchange resin according to claim 8, characterized in that: Degradation of the ion exchange resin tested in S3 and the total organic carbon content of the dissolved matter R a or organic oxygen demand R b , ammonia nitrogen or sulfate content R c , methanol R d and trimethylamine R e The contents were obtained according to the following formula: or ; or ; or ; or ; or ; in: C TOC —TOC content in the effluent Q, in mg / L; V L —The volume of the effluent Q, in L; M —The mass of the ion exchange resin to be tested, in kg; C COD —chemical oxygen demand in the effluent Q, in mg / L; C N(S) — C N or C S , C N is the ammonia nitrogen content in the effluent Q, C S is the sulfate content in the effluent Q, in mg / L; C 甲醇 —Methanol concentration, in mg / L; V Q —The total volume of gas in the first gas collector (10) and the second gas collector (16), in L; C 三甲胺 —Concentration of trimethylamine, in mg / L; V —The volume of the ion exchange resin to be tested, in L; R a 、 R b 、 R c 、 R d and R e The unit is mg / kg 湿树脂 or mg / L 湿树脂 .

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