Pyridine adsorption resin and preparation method thereof and method for treating pyridine-containing waste liquid

Abstract

The present invention relates to the technical field of waste liquid treatment, and in particular to a pyridine adsorption resin and a preparation method thereof and a treatment method for pyridine-containing waste liquid. The preparation method of the pyridine adsorption resin comprises the following steps: mixing a macroporous resin and an organic solvent to swell the macroporous resin to obtain a first intermediate liquid; mixing the first intermediate liquid and a metal salt to allow a portion of the metal salt to enter the pores of the macroporous resin to obtain a second intermediate liquid; removing the organic solvent in the second intermediate liquid, and adding an acid solution during the removal of the organic solvent to obtain a third intermediate liquid; washing away the acid solution to obtain the pyridine adsorption resin. The above method can prepare a pyridine adsorption resin with good adsorption performance and good stability.

Description

Technical Field

[0001] The invention relates to the technical field of waste liquid treatment, and in particular to a pyridine adsorption resin and a preparation method thereof, and a method for treating pyridine-containing waste liquid. Background Art

[0002] Pyridine is a common organic solvent, widely used in chemical synthesis, pharmaceutical preparations, pesticides and other fields. However, the toxicity and environmental pollution of pyridine have attracted people's attention. Therefore, it is of great significance to develop a material and method for efficiently removing pyridine. Various methods for removing pyridine have been proposed, including oxidative degradation, photocatalytic degradation, and biodegradation. Among them, adsorption is a simple and efficient method for removing pyridine. Existing adsorption materials mainly include activated carbon, MOFs, macroporous resins, etc. These materials remove pyridine molecules from the solution by adsorbing them.

[0003] However, there are some problems with existing adsorption materials. First, the adsorption performance of activated carbon is affected by impurities and the pH value of the solution, and the adsorption effect is unstable. Secondly, the adsorption capacity of macroporous resin adsorption materials is limited, and the adsorption is unstable. In addition, the preparation cost of MOFs materials is high, and they are easily interfered by other components in the environment. Moreover, in the waste liquid treatment process containing pyridine, after the adsorption of pyridine, the waste liquid is usually recovered and processed. The pyridine adsorption material is required to have a high pyridine adsorption capacity and high stability to avoid the introduction of other impurity elements during the adsorption of pyridine, which will affect the subsequent waste liquid recovery.

[0004] Therefore, a new pyridine removal material is needed to overcome the above problems. Summary of the invention

[0005] The invention provides a pyridine adsorption resin and a preparation method thereof, and a method for treating pyridine-containing waste liquid.

[0006] The first aspect of the present invention provides a method for preparing a pyridine adsorption resin, and the technical scheme thereof is as follows:

[0007] A method for preparing a pyridine adsorption resin comprises the following steps:

[0008] Mixing a macroporous resin and an organic solvent to swell the macroporous resin to obtain a first intermediate solution;

[0009] mixing the first intermediate solution and a metal salt so that a portion of the metal salt enters the pores of the macroporous resin to obtain a second intermediate solution;

[0010] removing the organic solvent in the second intermediate liquid, and adding acid during the process of removing the organic solvent to obtain a third intermediate liquid;

[0011] The acid solution is washed away to obtain the pyridine adsorption resin.

[0012] A second aspect of the present invention provides a pyridine adsorption resin, which is prepared by the preparation method described above.

[0013] The third aspect of the present invention provides a method for treating pyridine-containing waste liquid, and its technical scheme is as follows:

[0014] A method for treating pyridine-containing waste liquid comprises the following steps:

[0015] Adsorbing the pyridine-containing waste liquid with the pyridine adsorption resin as described above to obtain a waste liquid intermediate;

[0016] The waste liquid intermediate is recycled.

[0017] Compared with the traditional solution, the present invention has the following beneficial effects:

[0018] The present invention provides a novel preparation method of pyridine adsorption resin, which uses macroporous resin as a carrier, makes the macroporous resin swell in an organic solvent in advance, utilizes the pores of the swollen macroporous resin to load metal salts, removes the organic solvent, and adsorbs pyridine through the coordination of metal ions and N on the pyridine ring, so as to achieve the effect of efficient, stable and low-cost adsorption of pyridine. And after the metal salt is loaded into the pores of the swollen macroporous resin, a part of the metal salt will remain on the surface of the macroporous resin, which is difficult to remove in subsequent washing. When it remains on the surface of the macroporous resin, when the pyridine adsorption resin is used to adsorb the waste liquid containing pyridine, it will fall off and enter the waste liquid, affecting the subsequent waste liquid recovery and treatment. In the present invention, while removing the organic solvent, acid solution is added, and the acid solution can take away the metal salts remaining on the surface of the macroporous resin. When the acid solution is washed away, the metal salts on the surface of the macroporous resin are also washed away. The obtained pyridine adsorption resin has high stability and good market application prospects.

[0019] In general, the method of the present invention has the following advantages: 1) the macroporous resin has a large adsorption capacity and can better adsorb pyridine molecules; 2) the coordination effect between metal and pyridine makes the adsorption effect more stable and reliable; 3) the loading method of metal salt reduces the preparation cost of the material. 4) when the pyridine adsorption resin is used to adsorb the waste liquid containing pyridine, the metal salt is not easy to fall off and enter the waste liquid, affecting the subsequent waste liquid recovery and treatment.

[0020] In summary, the present invention provides a new material and method for removing pyridine, which has high adsorption efficiency and stability and can be applied to environmental pollution control and industrial production of pyridine. In addition, the material synthesized by the method of the present invention has good environmental and economic effects, simple operation steps, and relatively mild reaction conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention and to more completely understand the present invention and its beneficial effects, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0022] Figure 1 This is a physical picture of the pyridine adsorption resin of Example 1;

[0023] Figure 2 is a SEM image of the pyridine adsorption resin of Example 1;

[0024] Figure 3 is the XRD pattern of the pyridine adsorption resin of Example 1;

[0025] Figure 4 Schematic diagram of the coordination between iron ions and pyridine in the pores of the pyridine adsorption resin of Example 1. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below in conjunction with specific embodiments. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0028] the term

[0029] Unless otherwise specified or incompatible herewith, the terms and phrases used herein shall have the following meanings:

[0030] In the present invention, "plurality", "multiple", "multiple times", "multiple" and the like, unless otherwise specified, refer to a number greater than or equal to 2. For example, "one or more" means one or greater than or equal to two.

[0031] In the present invention, "optionally", "optional" and "optional" refer to optional, that is, to any one of the two parallel schemes of "yes" or "no". If multiple "options" appear in a technical solution, unless otherwise specified and there is no contradiction or mutual restriction, each "optional" is independent.

[0032] In the present invention, in the "first aspect", "second aspect", "third aspect", "fourth aspect", etc., the terms "first", "second", "third", "fourth", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or quantity, nor can they be understood as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first", "second", "third", "fourth", etc. only serve the purpose of non-exhaustive enumeration and description, and it should be understood that they do not constitute a closed limitation on quantity.

[0033] In the present invention, when it comes to numerical intervals (i.e., numerical ranges), unless otherwise specified, the optional numerical distribution is considered continuous within the above numerical interval, and includes the two numerical endpoints (i.e., the minimum value and the maximum value) of the numerical range, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to the integers within the numerical interval, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints. In this article, it is equivalent to directly listing each integer, such as t is an integer selected from 1 to 10, indicating that t is any integer selected from the group of integers consisting of 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10. In addition, when multiple ranges are provided to describe features or characteristics, these ranges can be combined. In other words, unless otherwise specified, the ranges disclosed herein should be understood to include any and all sub-ranges included therein.

[0034] The temperature parameters in the present invention, if not specifically limited, are allowed to be either constant temperature treatment or to vary within a certain temperature range. It should be understood that the constant temperature treatment allows the temperature to fluctuate within the precision range controlled by the instrument. Fluctuations within the range of ±5°C, ±4°C, ±3°C, ±2°C, and ±1°C are allowed.

[0035] In the present invention, when it comes to percentage content, unless otherwise specified, for solid-liquid mixing and solid-solid mixing, it refers to mass percentage, and for liquid-liquid mixing, it refers to volume percentage.

[0036] In the present invention, when it comes to percentage concentration, unless otherwise specified, it refers to the final concentration. The final concentration refers to the proportion of the added component in the system after the addition of the component.

[0037] In the present invention, % (w / w) and wt% both represent weight percentage, % (v / v) refers to volume percentage, and % (w / v) refers to mass volume percentage.

[0038] Traditional pyridine adsorption materials include activated carbon, which has a large specific surface area and rich pore structure and can effectively adsorb pyridine molecules. However, under high temperature or high humidity conditions, the adsorption efficiency of activated carbon will be affected. In recent years, with the increasing requirements for environmental protection, the research on adsorption materials for removing pyridine has continued to deepen, and researchers have tried to modify and synthesize new adsorption materials for the adsorption of pyridine. For example, nanomaterials such as metal oxides and carbon nanotubes are used to adsorb pyridine. In addition, functionalized polymer materials have also been used for the adsorption of pyridine. By regulating the structure and functional groups of the polymer, the selective adsorption of pyridine can be achieved. In addition, the development of some new materials has also provided new ideas for the adsorption of pyridine. For example, metal organic framework (MOF) is a material with a highly porous structure and controllability, which has been used to adsorb organic pollutants such as pyridine. In addition, materials with special surface properties such as graphene and silica gel also show good adsorption capacity for pyridine.

[0039] Different from the above-mentioned adsorption materials, the first aspect of the present invention provides a method for preparing a novel pyridine adsorption resin. In some embodiments, a method for preparing a pyridine adsorption resin comprises the following steps:

[0040] S10, mixing a macroporous resin and an organic solvent to swell the macroporous resin to obtain a first intermediate solution.

[0041] The macroporous resin has a large specific surface area, and after the metal salt is loaded in the pores, the adsorption efficiency of pyridine is high. At the same time, the macroporous resin is acid-resistant, alkali-resistant, corrosion-resistant, and has good stability. Optionally, the macroporous resin is selected from a styrene-based macroporous resin.

[0042] Optionally, the porosity of the macroporous resin is 65% to 75%;

[0043] Optionally, the pore size of the macroporous resin is 10 nm to 1000 nm;

[0044] Optionally, the average particle size of the macroporous resin is 30 mesh to 60 mesh;

[0045] Optionally, the chlorine content of the macroporous resin is 15 wt% to 18 wt%.

[0046] The macroporous resin can be commercially available, for example, purchased from Shanghai Resin Factory.

[0047] Optionally, the organic solvent is selected from a mixture of one or more of N,N-dimethylformamide, dimethyl sulfoxide, 1,2-dichloroethane and ethanol.

[0048] Optionally, the mass ratio of the macroporous resin to the organic solvent is 1:(3-6).

[0049] Optionally, the conditions for swelling the macroporous resin include: heating to 40° C. to 60° C. for 2 h to 6 h.

[0050] S20, mixing the first intermediate solution and the metal salt so that a portion of the metal salt enters the pores of the macroporous resin to obtain a second intermediate solution.

[0051] It is understandable that the metal salt is an oil-soluble metal salt. Optionally, the metal salt is selected from a mixture of one or more of aluminum chloride, ferric chloride, cupric chloride and nickel chloride. The metal salt can be dissolved in an organic solvent.

[0052] Optionally, mixing the first intermediate solution and the metal salt so that a portion of the metal salt enters the pores of the macroporous resin comprises the following steps:

[0053] Under stirring conditions, the metal salt is added to the first intermediate solution in batches, and heated under reflux to allow a portion of the metal salt to enter the pores of the macroporous resin.

[0054] Optionally, the mass ratio of the metal salt to the macroporous resin in each batch is independently 1:(3-6);

[0055] Optionally, the stirring time after adding the metal salt in each batch is independently 0.5h to 2h;

[0056] Optionally, the total number of batches is 2 to 5 times;

[0057] Optionally, the heating reflux time is 16h to 24h;

[0058] Optionally, the heating reflux temperature is 80°C to 90°C.

[0059] S30, removing the organic solvent in the second intermediate liquid, and adding acid during the process of removing the organic solvent to obtain a third intermediate liquid.

[0060] Optionally, the method of removing the organic solvent is distillation.

[0061] The acid solution is added during the process of removing the organic solvent, comprising the following steps:

[0062] A portion of the organic solvent is removed, a portion of the acid solution is added, and the remaining portion of the organic solvent is continued to be removed. During the process of removing the remaining portion of the organic solvent, the remaining portion of the acid solution is added.

[0063] Optionally, the mass ratio of the portion of the acid solution to the mass ratio of the macroporous resin is 1:(3-5);

[0064] Optionally, the mass ratio of the remaining part of the acid solution to the mass ratio of the macroporous resin is 1:(3-5).

[0065] Optionally, the acid solution is a mixture of one or more of an aqueous solution of hydrochloric acid, an aqueous solution of sulfuric acid and an aqueous solution of nitric acid.

[0066] Optionally, the mass fraction of hydrochloric acid in the aqueous solution of hydrochloric acid is 5% to 15%;

[0067] Optionally, the mass fraction of sulfuric acid in the aqueous solution of sulfuric acid is 5% to 15%;

[0068] Optionally, the mass fraction of nitric acid in the aqueous solution of nitric acid is 5% to 15%.

[0069] S40, washing away the acid solution to obtain the pyridine adsorption resin.

[0070] The acid can be washed away with water.

[0071] The above-mentioned preparation method uses macroporous resin as a carrier, so that the macroporous resin is swollen in an organic solvent in advance, and the pores of the swollen macroporous resin are used to load metal salts, and then the organic solvent is removed, and pyridine is adsorbed by the coordination of metal ions with N on the pyridine ring, so as to achieve the effect of efficient, stable and low-cost adsorption of pyridine. And after the metal salt is loaded into the pores of the swollen macroporous resin, a part of the metal salt will also remain on the surface of the macroporous resin, and this part of the metal salt is difficult to remove in subsequent washings. When it remains on the surface of the macroporous resin, when the waste liquid containing pyridine is adsorbed by the pyridine adsorption resin, it will fall off and enter the waste liquid, affecting the subsequent waste liquid recycling. In the present invention, while removing the organic solvent, acid solution is added, and the acid solution can take away the metal salt remaining on the surface of the macroporous resin. While washing away the acid solution, the metal salt on the surface of the macroporous resin is also washed away. The stability of the obtained pyridine adsorption resin is high, and it has a good market application prospect.

[0072] In general, the above method has the following advantages: 1) The macroporous resin has a large adsorption capacity and can better adsorb pyridine molecules; 2) The coordination effect between metal and pyridine makes the adsorption effect more stable and reliable; 3) The loading method of metal salt reduces the preparation cost of the material. 4) When using pyridine adsorption resin to adsorb waste liquid containing pyridine, the metal salt is not easy to fall off and enter the waste liquid, affecting the subsequent waste liquid recovery and treatment.

[0073] In summary, the present invention provides a new material and method for removing pyridine, which has high adsorption efficiency and stability and can be applied to environmental pollution control and industrial production of pyridine. In addition, the material synthesized by the method of the present invention has good environmental and economic effects, simple operation steps, and relatively mild reaction conditions.

[0074] The second aspect of the present invention provides a pyridine adsorption resin, which is prepared by the above preparation method. The pyridine adsorption resin is suitable for efficiently removing and recovering pyridine from industrial waste liquid, thereby protecting the environment and human health.

[0075] A third aspect of the present invention provides a method for treating pyridine-containing waste liquid, which, in some embodiments, comprises the following steps:

[0076] S1. Using the pyridine adsorption resin to adsorb the pyridine-containing waste liquid to obtain a waste liquid intermediate.

[0077] It can be understood that the pyridine adsorption resin can be loaded into the packed column, and the resin can be washed with 3 to 5 BV of clean water before use, and then the waste liquid containing pyridine is added for adsorption. After the adsorption is completed, the waste liquid intermediate flows out.

[0078] S2. Recycling the waste liquid intermediate.

[0079] Optionally, the method further comprises a step of analyzing the pyridine adsorption resin adsorbed with pyridine. For example, after adsorption saturation, an alkaline solution is used at a temperature of 40 to 55° C. to analyze and regenerate the pyridine adsorption resin adsorbed with pyridine.

[0080] Optionally, the analytical solution is an alkaline solution. Further optionally, the analytical solution is a mixture of one or more selected from an aqueous solution of sodium hydroxide, an aqueous solution of potassium hydroxide and an aqueous solution of barium hydroxide.

[0081] Optionally, the mass fraction of sodium hydroxide in the aqueous solution of sodium hydroxide is 5% to 10%.

[0082] Optionally, the mass fraction of potassium hydroxide in the aqueous solution of potassium hydroxide is 5% to 10%.

[0083] Optionally, the mass fraction of barium hydroxide in the aqueous solution of barium hydroxide is 5% to 10%.

[0084] The above method can be used to solve the removal and recovery of pyridine in industrial production waste liquid, and achieve the recycling of resin through a relatively simple regeneration process.

[0085] The following is further described in conjunction with specific embodiments and comparative examples. The raw materials involved in the following specific embodiments and comparative examples, unless otherwise specified, can all be commercially available, the instruments used, unless otherwise specified, can all be commercially available, and the processes involved, unless otherwise specified, are all routinely selected by those skilled in the art.

[0086] Example 1

[0087] This embodiment provides a pyridine adsorption resin and a preparation method thereof and a method for treating pyridine-containing waste liquid, and the steps are as follows:

[0088] (a) Mix the purchased macroporous resin and 1,2-dichloroethane in a mass ratio of 1:5, heat to 40° C., and swell for 2 h to obtain a first intermediate solution;

[0089] (b) adding ferric chloride to the first intermediate solution of step (a) in batches, wherein the mass ratio of ferric chloride to macroporous resin added in each batch is 1:5, stirring for 1 hour after the previous batch is added and then adding the next batch, after adding 3 batches in total, heating to 84° C. and reflux for 16 hours to obtain a second intermediate solution;

[0090] (c) maintaining the temperature of the second intermediate solution in step (b) at 84° C., distilling off 1,2-dichloroethane in the reaction system until the resin can be stirred, adding a 10% hydrochloric acid aqueous solution, the mass ratio of the acid solution to the macroporous resin being 1:3, continuing to distill off 1,2-dichloroethane in the reaction system, and simultaneously using a constant pressure funnel to dropwise add a 10% hydrochloric acid aqueous solution until no 1,2-dichloroethane can be distilled off (i.e., the reaction system is entirely made up of the added acid solution), at which time the mass ratio of the subsequently added acid solution to the macroporous resin is approximately 1:3, maintaining for 1 hour and then stopping heating to obtain a third intermediate solution;

[0091] (d) The third intermediate liquid of step (c) is rinsed with pure water for 3 times, and then soaked in hot water for 2 hours. If the hot water changes color during soaking, the water needs to be changed and soaked for a long time. After repeated several times, the upper liquid of the soaking is clear, and the pyridine adsorption resin is obtained by solid-liquid separation;

[0092] The actual picture of the obtained pyridine adsorption resin is as follows Figure 1 As shown in the scanning electron microscope (SEM) image Figure 2 As shown, Figure 2 a is the magnification of 300 microns, Figure 2 The magnification of b is 5 microns. The XRD pattern of the obtained pyridine adsorption resin is as follows Figure 3 As shown, from Figure 3 It can be seen that obvious diffraction peaks appear at 2θ of 33.0°, 35.7°, and 54°, indicating that ferric chloride is loaded in the pyridine adsorption resin.

[0093] (e) 10 mL (7.8 g) of the pyridine adsorption resin of step (d) was loaded into a packed column for adsorption, the resin was first rinsed with 5 BV of clean water, and then a pyridine waste liquid (wherein, the content of pyridine was 200 ppm and the content of ferric chloride was 0 ppm) was introduced for adsorption, Figure 4The figure is a schematic diagram of the coordination of iron ions and pyridine in the pores of the pyridine adsorption resin. After the adsorption is completed, the waste liquid intermediate flows through a 0.45 micron membrane, and the pyridine content is determined by liquid chromatography, and the ferric chloride content is determined by ICP. The results are shown in Table 1. After the adsorption is saturated, a 10% sodium hydroxide aqueous solution is used at a temperature of 50°C for desorption regeneration.

[0094] Example 2

[0095] This embodiment provides a pyridine adsorption resin and a preparation method thereof and a method for treating pyridine-containing waste liquid, and the steps are as follows:

[0096] (a) Mix the purchased macroporous resin and 1,2-dichloroethane in a mass ratio of 1:5, heat to 40° C., and swell for 2 h to obtain a first intermediate solution;

[0097] (b) adding aluminum chloride to the first intermediate solution of step (a) in batches, with the mass ratio of aluminum chloride to macroporous resin added in each batch being 1:5, stirring for 1 hour after the previous batch is added before adding the next batch, and after adding 3 batches in total, heating to 84° C. and reflux for 16 hours to obtain a second intermediate solution;

[0098] (c) maintaining the temperature of the second intermediate solution in step (b) at 84° C., distilling off 1,2-dichloroethane in the reaction system until the resin can be stirred, adding a 10% hydrochloric acid aqueous solution, the mass ratio of the acid solution to the macroporous resin being 1:3, continuing to distill off 1,2-dichloroethane in the reaction system, and simultaneously using a constant pressure funnel to dropwise add a 10% hydrochloric acid aqueous solution until no 1,2-dichloroethane can be distilled off (i.e., the reaction system is entirely made up of the added acid solution), at which time the mass ratio of the subsequently added acid solution to the macroporous resin is approximately 1:3, maintaining for 1 hour and then stopping heating to obtain a third intermediate solution;

[0099] (d) The third intermediate liquid of step (c) is rinsed with pure water for 3 times, and then soaked in hot water for 2 hours. If the hot water changes color during soaking, the water needs to be changed and soaked for a long time. After repeated several times, the upper liquid of the soaking is clear, and the pyridine adsorption resin is obtained by solid-liquid separation;

[0100] (e) The pyridine adsorption resin of step (d) was loaded into a packed column for adsorption, and the resin was first rinsed with 5 BV of clean water, and then a waste liquid containing pyridine (wherein the content of pyridine was 200 ppm and the content of aluminum chloride was 0 ppm) was introduced for adsorption, and the waste liquid intermediate liquid flowing out was passed through a 0.45 μm membrane, and the content of pyridine was determined by liquid chromatography, and the content of aluminum chloride was determined by ICP, and the results were shown in Table 1. After the adsorption was completed, a sodium hydroxide aqueous solution with a mass fraction of 10% was used at a temperature of 50° C. for desorption and regeneration.

[0101] Example 3

[0102] This embodiment provides a pyridine adsorption resin and a preparation method thereof and a method for treating pyridine-containing waste liquid, and the steps are as follows:

[0103] (a) Mix the purchased macroporous resin and 1,2-dichloroethane in a mass ratio of 1:5, heat to 40° C., and swell for 2 h to obtain a first intermediate solution;

[0104] (b) adding copper chloride to the first intermediate solution of step (a) in batches, with the mass ratio of copper chloride to macroporous resin added in each batch being 1:5, stirring for 1 hour after the previous batch is added before adding the next batch, and after a total of 3 batches are added, heating to 84° C. and reflux for 16 hours to obtain a second intermediate solution;

[0105] (c) maintaining the temperature of the second intermediate liquid in step (b) at 84° C., distilling off 1,2-dichloroethane in the reaction system until the resin can be stirred, adding a 10% sulfuric acid aqueous solution, the mass ratio of the acid solution to the macroporous resin being 1:3, continuing to distill off 1,2-dichloroethane in the reaction system, and simultaneously using a constant pressure funnel to dropwise add a 10% sulfuric acid aqueous solution until no 1,2-dichloroethane can be distilled off (i.e., the reaction system is entirely made up of the added acid solution), at which time the mass ratio of the subsequently added acid solution to the macroporous resin is approximately 1:3, maintaining for 1 hour and then stopping heating to obtain a third intermediate liquid;

[0106] (d) The third intermediate liquid of step (c) is rinsed with pure water for 3 times, and then soaked in hot water for 2 hours. If the hot water changes color during soaking, the water needs to be changed and soaked for a long time. After repeated several times, the upper liquid of the soaking is clear, and the pyridine adsorption resin is obtained by solid-liquid separation;

[0107] (e) The pyridine adsorption resin of step (d) was loaded into a packed column for adsorption, and the resin was first rinsed with 5 BV of clean water, and then a waste liquid containing pyridine (wherein the content of pyridine was 200 ppm and the content of cupric chloride was 0 ppm) was introduced for adsorption, and the waste liquid intermediate liquid flowing out was passed through a 0.45 μm membrane, and the content of pyridine was determined by liquid chromatography, and the content of cupric chloride was determined by ICP, and the results were shown in Table 1. After the adsorption was completed, a sodium hydroxide aqueous solution with a mass fraction of 10% was used at a temperature of 50° C. for desorption and regeneration.

[0108] Comparative Example 1

[0109] This comparative example provides a pyridine adsorption resin and a preparation method thereof and a method for treating pyridine-containing waste liquid. The steps are basically the same as those in Example 1, with the main difference being that: acid solution is not added in step (c), specifically:

[0110] (a)-(b) are the same as in Example 1;

[0111] (c) maintaining the temperature of the second intermediate liquid in step (b) at 84° C., distilling off 1,2-dichloroethane in the reaction system until no more 1,2-dichloroethane can be distilled off, and then stopping heating after maintaining for 1 hour to obtain a third intermediate liquid;

[0112] (d)-(e) are the same as in Example 1.

[0113] Table 1

[0114]

[0115] It can be seen that the adsorption resins of Examples 1-3 have excellent adsorption performance for pyridine, among which Example 2 has the best measured effect. Compared with Comparative Example 1, the adsorption resin of Example 1 has high stability.

[0116] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0117] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for preparing a pyridine adsorption resin, characterized in that: The following steps are involved: Mixing a macroporous resin and an organic solvent to swell the macroporous resin to obtain a first intermediate solution, wherein the macroporous resin is selected from a styrene-based macroporous resin; Mixing the first intermediate solution and a metal salt so that a portion of the metal salt enters the pores of the macroporous resin to obtain a second intermediate solution, wherein the metal salt is selected from a mixture of one or more of aluminum chloride, ferric chloride, copper chloride and nickel chloride; removing a portion of the organic solvent in the second intermediate solution, adding a portion of the acid solution, continuing to remove the remaining portion of the organic solvent, and adding the remaining portion of the acid solution during the process of removing the remaining portion of the organic solvent, wherein the acid solution can remove the metal salt remaining on the surface of the macroporous resin, to obtain a third intermediate solution; The acid solution is washed away to obtain the pyridine adsorption resin.

2. The method for preparing a pyridine adsorption resin according to claim 1, characterized in that: The acid solution is a mixture of one or more of an aqueous solution of hydrochloric acid, an aqueous solution of sulfuric acid and an aqueous solution of nitric acid.

3. The method for preparing a pyridine adsorption resin according to claim 2, characterized in that: Includes one or more of the following characteristics: (1) The mass fraction of hydrochloric acid in the aqueous solution of hydrochloric acid is 5% to 15%; (2) The mass fraction of sulfuric acid in the aqueous solution of sulfuric acid is 5% to 15%; (3) The mass fraction of nitric acid in the aqueous solution of nitric acid is 5% to 15%.

4. The method for preparing a pyridine adsorption resin according to claim 1, characterized in that: The mass ratio of the portion of the acid solution to the macroporous resin is 1:(3-5).

5. The method for preparing a pyridine adsorption resin according to claim 1, characterized in that: The mass ratio of the remaining acid solution to the macroporous resin is 1:(3-5).

6. The method for preparing a pyridine adsorption resin according to any one of claims 1 to 5, characterized in that: The organic solvent is selected from a mixture of one or more of N,N-dimethylformamide, dimethyl sulfoxide, 1,2-dichloroethane and ethanol.

7. The method for preparing a pyridine adsorption resin according to claim 6, characterized in that: The macroporous resin satisfies at least one of the following conditions: (1) The porosity of the macroporous resin is 65% to 75%; (2) The pore size of the macroporous resin is 10 nm to 1000 nm; (3) The average particle size of the macroporous resin is 30 mesh to 60 mesh; (4) The chlorine content of the macroporous resin is 15wt%~18wt%.

8. The method for preparing a pyridine adsorption resin according to any one of claims 1 to 5 and 7, characterized in that: Mixing the first intermediate solution and the metal salt so that a portion of the metal salt enters the pores of the macroporous resin comprises the following steps: Under stirring conditions, the metal salt is added to the first intermediate solution in batches, and heated under reflux to allow a portion of the metal salt to enter the pores of the macroporous resin.

9. The method for preparing a pyridine adsorption resin according to claim 8, characterized in that: At least one of the following conditions is met: (1) The mass ratio of the metal salt to the macroporous resin in each batch is independently 1:(3-6); (2) The stirring time after adding the metal salt of each batch is independently 0.5h~2h; (3) The total number of batches is 2 to 5; (4) Heating reflux time 16h~24h; (5) The heating reflux temperature is 80℃~90℃.

10. The method for preparing a pyridine adsorption resin according to any one of claims 1 to 5, 7 and 9, characterized in that: At least one of the following conditions is met: (1) The mass ratio of the macroporous resin to the organic solvent is 1:(3-6); (2) The conditions for swelling the macroporous resin include: heating to 40° C. to 60° C. for 2 h to 6 h.

11. A pyridine adsorption resin, characterized in that: Prepared by the preparation method according to any one of claims 1 to 10.

12. A method for treating pyridine-containing waste liquid, characterized in that: The following steps are involved: Adsorbing the pyridine-containing waste liquid using the pyridine adsorption resin according to claim 11 to obtain a waste liquid intermediate; The waste liquid intermediate is recycled.

Images