CN113274985A - Adsorbent for removing iodine and preparation method thereof - Google Patents
Adsorbent for removing iodine and preparation method thereof Download PDFInfo
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- CN113274985A CN113274985A CN202110354632.8A CN202110354632A CN113274985A CN 113274985 A CN113274985 A CN 113274985A CN 202110354632 A CN202110354632 A CN 202110354632A CN 113274985 A CN113274985 A CN 113274985A
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- adsorbent
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/22—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising organic material
- B01J20/26—Synthetic macromolecular compounds
- B01J20/261—Synthetic macromolecular compounds obtained by reactions only involving carbon to carbon unsaturated bonds
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D15/00—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor
- B01D15/08—Selective adsorption, e.g. chromatography
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
- C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
- C08F220/10—Esters
- C08F220/12—Esters of monohydric alcohols or phenols
- C08F220/14—Methyl esters, e.g. methyl (meth)acrylate
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F226/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a single or double bond to nitrogen or by a heterocyclic ring containing nitrogen
- C08F226/06—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a single or double bond to nitrogen or by a heterocyclic ring containing nitrogen by a heterocyclic ring containing nitrogen
- C08F226/10—N-Vinyl-pyrrolidone
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2220/00—Aspects relating to sorbent materials
- B01J2220/40—Aspects relating to the composition of sorbent or filter aid materials
- B01J2220/48—Sorbents characterised by the starting material used for their preparation
- B01J2220/4812—Sorbents characterised by the starting material used for their preparation the starting material being of organic character
Abstract
The invention relates to an adsorbent for removing radioactive iodide ions and a preparation method thereof, wherein the adsorbent has a structure shown as a structural formula (I), wherein m: n = 1-5: 50, molecular weight distribution of 1-1.5, number average molecular weight Mn=1.0×104–5.0×104 g mol‑1Weight average molecular weight Mw=1.0×104–7.5×104 g·mol‑1. The preparation method of the adsorbent comprises the following steps: 1) dispersing N-vinyl pyrrolidone in deionized water, adding potassium persulfate initiator, performing ultrasonic dispersion treatment for 30min, pouring the solutionPutting the mixture into a three-mouth bottle, introducing nitrogen for protection, and slowly dropwise adding methyl methacrylate for polymerization at a certain temperature; filtering the product obtained in the step 1), circularly cleaning for 3 times by using ethanol/deionized water, and drying in vacuum to obtain the adsorbent.
Description
Technical Field
The invention relates to the field of adsorption materials, and particularly relates to an adsorbent for removing iodine and a preparation method thereof.
Background
Radioiodine refers to a radioactive isotope of iodine, consisting essentially of123I、124I、125I、129I、131I, and the like. Radioactive iodine, one of the products of nuclear fission, is widely present in nuclear fission waste liquids, to131The form I has a half-life of from 8.04 days to 1.57X 107The water can flow in natural water bodies for different years, and can enter aquatic environments such as oceans, rivers, underground water and the like without being treated, so that the ecological environment and the human health are greatly damaged; in addition, radioiodine is also widely used in the medical field, for example131I is used for treating hyperthyroidism and thyroid cancer,125the kit I is used for thyroid tumor biopsy, thyroid scanning, radioimmunoassay and the like. Radioactive iodine has great harm to human body, can cause diseases such as surrogate disorder, leukemia, thyroid cancer and the like due to accumulation in human body, and is listed as a carcinogen by the world health organization at present. Therefore, designing to prepare suitable materials for efficient capture and storage of iodine is critical to public safety.
In the prior art, for removing I-The method mainly comprises surface adsorption, ion exchange, chemical precipitation, solvent extraction, membrane separation and the like. Although there are many methods for removing iodide ions, most of the methods have low removal efficiency, and the partially efficient removal method is accompanied by high cost, thereby restricting the popularization and application of the related methods. In addition, the above adsorbent is affected by PH, temperature and solvent, and the fluctuation of adsorption rate is large, and it cannot exhibit good adsorption performance. The adsorption method is an effective mode for removing iodide ions, and has the advantages of convenient operation, high efficiency, low cost and the like; however, the adsorption effect of the adsorption method on iodine depends on the acting force between the adsorption material and the iodine, and the dynamic adsorption processThe lack of the medium stable acting force easily causes desorption even if iodine is adsorbed, thereby affecting the adsorption effect. Therefore, the development of an adsorbent that efficiently removes radioactive iodide ions is critical to ensure efficient performance of such methods. In the prior adsorption technology, the adsorption rate for removing radioactive iodide ions is low, the desorption is easy, the cost is high, the preparation process is complex, and in addition, the adsorption rate of the adsorbent is greatly fluctuated under the influence of temperature and solvent.
Disclosure of Invention
The invention provides an adsorbent for removing iodine and a preparation method thereof, and solves the problems that the existing adsorbent is low in adsorption rate, easy to resolve, high in cost, complex in preparation process, and greatly fluctuated in adsorption rate due to the influence of temperature and solvent.
In order to solve the above problems, an aspect of the present invention provides an adsorbent for removing iodine having a structure represented by structural formula (i):
（Ⅰ）
wherein m: n = 1-5: 50, PDI of 1 to 1.5, number average molecular weight Mn=1.0×104–5.0×104 g mol-1Weight average molecular weight Mw =1.0×104–7.5×104 g·mol-1Measured by GPC.
Another aspect of the present invention provides a method for preparing an adsorbent for removing iodine, which comprises the following steps:
the more specific preparation method comprises the following steps:
1) dispersing N-vinyl pyrrolidone (NVP) in deionized water, adding a potassium persulfate (KPS) initiator, performing ultrasonic dispersion treatment for 30min, pouring the solution into a three-necked bottle, introducing nitrogen for protection, and slowly dropwise adding Methyl Methacrylate (MMA) at a certain temperature;
2) filtering the product obtained in the step 1), circularly cleaning for 3 times by using ethanol/deionized water, and drying in vacuum to obtain white powdery polymer nano adsorbent (PNM NPs).
Preferably, the mass ratio of the N-vinyl pyrrolidone (NVP) to the Methyl Methacrylate (MMA) in the step 1) is 1-4: 1.
Preferably, the mass of potassium persulfate (KPS) in the step 1) is 0.54-1.34% of the sum of the mass of N-vinylpyrrolidone (NVP) and Methyl Methacrylate (MMA).
Preferably, the polymerization temperature in the step 1) is 50 ℃ to 70 ℃.
Preferably, the polymerization reaction time in the step 1) is 24 h.
The invention provides an adsorbent for removing iodine and a preparation method thereof, wherein a novel iodine adsorbent with adjustable hydrophilicity and hydrophobicity is synthesized by a one-step method by introducing an active functional group-N-vinyl pyrrolidone and a hydrophobic monomer-methyl methacrylate which have strong iodine adsorption capability. The adsorbent for removing iodine prepared by the invention has the advantages of high adsorption rate, difficult desorption, low cost and simple preparation process. In addition, the adsorbent has higher adsorption efficiency in iodine solutions with different temperatures and different concentrations.
Detailed Description
The technical solutions of the present invention are further illustrated below by specific examples, and the terms used in the present invention have meanings generally understood by those of ordinary skill in the art unless otherwise specified. Also in the following examples, various processes and methods not described in detail are conventional methods well known in the art.
The technical solutions in the embodiments of the present invention are clearly and completely described below with reference to the embodiments, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the obtained embodiments. All other embodiments that can be derived from the embodiments of the present invention by a person of ordinary skill in the art are within the scope of the present invention.
Example 1
A method for preparing an adsorbent for removing iodine, comprising the steps of:
1) dispersing 2g N-vinyl pyrrolidone (NVP) in 100g of deionized water, adding 0.0216g of potassium persulfate (KPS) initiator, performing ultrasonic dispersion treatment for 30min, pouring the solution into a three-neck bottle, introducing nitrogen for protection, slowly and dropwise adding 2g of Methyl Methacrylate (MMA) at the temperature of 70 ℃, and performing polymerization reaction for 24 h;
2) filtering the product obtained in the step 1), circularly cleaning for 3 times by using ethanol/deionized water, and drying in vacuum to obtain white powdery polymer nano adsorbent (PNM NPs).
Example 2
A method for preparing an adsorbent for removing iodine, comprising the steps of:
1) dispersing 4g N-vinyl pyrrolidone (NVP) in 100g of deionized water, adding 0.0804g of potassium persulfate (KPS) initiator, performing ultrasonic dispersion treatment for 30min, pouring the solution into a three-neck bottle, introducing nitrogen for protection, slowly dropwise adding 2g of Methyl Methacrylate (MMA) at the temperature of 60 ℃, and performing polymerization reaction for 24 h;
2) filtering the product obtained in the step 1), circularly cleaning for 3 times by using ethanol/deionized water, and drying in vacuum to obtain white powdery polymer nano adsorbent (PNM NPs).
Example 3
A method for preparing an adsorbent for removing iodine, comprising the steps of:
1) dispersing 6g N-vinyl pyrrolidone (NVP) in 100g of deionized water, adding 0.08g of potassium persulfate (KPS) initiator, performing ultrasonic dispersion treatment for 30min, pouring the solution into a three-neck bottle, introducing nitrogen for protection, slowly and dropwise adding 2g of Methyl Methacrylate (MMA) at the temperature of 50 ℃, and performing polymerization reaction for 24 h;
2) filtering the product obtained in the step 1), circularly cleaning for 3 times by using ethanol/deionized water, and drying in vacuum to obtain white powdery polymer nano adsorbent (PNM NPs).
Example 4
A method for preparing an adsorbent for removing iodine, comprising the steps of:
1) dispersing 8g N-vinyl pyrrolidone (NVP) in 100g of deionized water, adding 0.134g of potassium persulfate (KPS) initiator, performing ultrasonic dispersion treatment for 30min, pouring the solution into a three-neck bottle, introducing nitrogen for protection, slowly and dropwise adding 2g of Methyl Methacrylate (MMA) at the temperature of 70 ℃, and performing polymerization reaction for 24 h;
2) filtering the product obtained in the step 1), circularly cleaning for 3 times by using ethanol/deionized water, and drying in vacuum to obtain white powdery polymer nano adsorbent (PNM NPs).
Example 5
A method for preparing an adsorbent for removing iodine, comprising the steps of:
1) dispersing 4g N-vinyl pyrrolidone (NVP) in 100g of deionized water, adding 0.06g of potassium persulfate (KPS) initiator, performing ultrasonic dispersion treatment for 30min, pouring the solution into a three-neck bottle, introducing nitrogen for protection, slowly and dropwise adding 2g of Methyl Methacrylate (MMA) at the temperature of 50 ℃, and performing polymerization reaction for 24 h;
2) filtering the product obtained in the step 1), circularly cleaning for 3 times by using ethanol/deionized water, and drying in vacuum to obtain white powdery polymer nano adsorbent (PNM NPs).
Example 6
A method for preparing an adsorbent for removing iodine, comprising the steps of:
1) dispersing 8g N-vinyl pyrrolidone (NVP) in 100g of deionized water, adding 0.134g of potassium persulfate (KPS) initiator, performing ultrasonic dispersion treatment for 30min, pouring the solution into a three-neck bottle, introducing nitrogen for protection, slowly and dropwise adding 2g of Methyl Methacrylate (MMA) at the temperature of 60 ℃, and performing polymerization reaction for 24 h;
2) filtering the product obtained in the step 1), circularly cleaning for 3 times by using ethanol/deionized water, and drying in vacuum to obtain white powdery polymer nano adsorbent (PNM NPs).
Adsorption test
0.05g of the nano-adsorbent (PNM NPs) prepared in examples 1 to 6 was added with solutions of different iodine concentrations (0.002 g/mL, 0.004 g/mL, 0.006 g/mL, 0.008 g/mL, 0.01 g/mL) and sonicated for 3 min to completely disperse the solution. Then placing the iodine concentration solution container in 60oC, directly reaching adsorption balance in a constant-temperature water bath oscillator; 3) centrifuging the suspension after iodine adsorption treatment, repeatedly centrifuging and washing with n-heptane for several times to remove residual iodine 40oC, vacuum drying is carried out, and yellow powdery polymer nano particles (PNM NPs-I) capable of adsorbing iodine can be obtained; and quantitatively measuring the content of iodine adsorbed on the surface of the sample by an iodometry method, and evaluating the adsorption performance of the sample.
TABLE 1 iodine solution concentration vs PNM2：2Effect of NPs iodine adsorption Capacity
PNM2：2The adsorption capacity of NPs to iodine increases along with the increase of the concentration of the iodine solution, which shows that the adsorption capacity can be effectively regulated and controlled by the concentration of the iodine solution.
0.05g of the nano-adsorbent (PNM NPs) prepared in examples 1-6 was added to a solution of iodine concentration of 0.006 g/mL and sonicated for 3 min to completely disperse the solution. Then placing a 0.006 g/mL iodine concentration solution container in 25, 35, 45 or 60 partsoC, directly reaching adsorption balance in a constant-temperature water bath oscillator; 3) centrifuging the suspension after iodine adsorption treatment, repeatedly centrifuging and washing with n-heptane for several times to remove residual iodine 40oC, vacuum drying is carried out, and yellow powdery polymer nano particles (PNM NPs-I) capable of adsorbing iodine can be obtained; and quantitatively measuring the content of iodine adsorbed on the surface of the sample by an iodometry method, and evaluating the adsorption performance of the sample.
TABLE 2 temperature vs. PNM2：2Effect of NPs iodine adsorption Capacity
PNM2：2The adsorption capacity of NPs to iodine increases along with the increase of temperature, which shows that the adsorption capacity can be effectively regulated and controlled by the adsorption temperature.
Claims (6)
1. An adsorbent for removing iodine, characterized in that: the adsorbent for removing iodine has a structure represented by the structural formula (I):
（Ⅰ）
wherein m: n = 1-5: 50, molecular weight distribution of 1-1.5, number average molecular weight Mn=1.0×104–5.0×104 g mol-1Weight average molecular weight Mw =1.0×104–7.5×104 g·mol-1Measured by GPC.
2. A method for preparing an adsorbent for removing iodine according to claim 1, comprising the steps of:
1) dispersing N-vinyl pyrrolidone (NVP) in deionized water, adding a potassium persulfate (KPS) initiator, performing ultrasonic dispersion treatment for 30min, pouring the solution into a three-necked bottle, introducing nitrogen for protection, slowly dropwise adding Methyl Methacrylate (MMA) at a certain temperature, and performing polymerization reaction for a certain time;
2) filtering the product obtained in the step 1), circularly cleaning for 3 times by using ethanol/deionized water, and drying in vacuum to obtain white powdery polymer nano adsorbent (PNM NPs).
3. The method for producing an adsorbent for removing radioactive iodide ions according to claim 2, wherein: the mass ratio of the N-vinyl pyrrolidone (NVP) to the Methyl Methacrylate (MMA) in the step 1) is 1-4: 1.
4. The method of producing an adsorbent for removing iodine according to claim 2 or 3, characterized in that: the mass of the potassium persulfate (KPS) in the step 1) is 0.54-1.34% of the sum of the mass of the N-vinyl pyrrolidone (NVP) and the mass of the Methyl Methacrylate (MMA).
5. The method of preparing an adsorbent for removing iodine according to claim 2, wherein: the polymerization temperature in the step 1) is 50-70 ℃.
6. The method of preparing an adsorbent for removing iodine according to claim 2, wherein: the polymerization reaction time in the step 1) is 24 hours.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE619168A (en) * | 1961-06-20 | 1962-12-20 | Rohm & Haas | Polymers of N-vinylpyrrolidinone and their production process |
| JPH06296626A (en) * | 1993-04-15 | 1994-10-25 | Morita Tokyo Seisakusho:Kk | Dental diagnostic device with bactericidal water producing device |
| CN105542059A (en) * | 2015-11-25 | 2016-05-04 | 深圳市昌华生物医学工程有限公司 | Synthetic method of methyl methacrylate and N-vinyl pyrrolidone copolymer |
| CN108219066A (en) * | 2018-01-11 | 2018-06-29 | 东莞理工学院 | A kind of nanometer of povidone-iodine antibacterial dyestuff and preparation method thereof |
-
2021
- 2021-04-01 CN CN202110354632.8A patent/CN113274985A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE619168A (en) * | 1961-06-20 | 1962-12-20 | Rohm & Haas | Polymers of N-vinylpyrrolidinone and their production process |
| JPH06296626A (en) * | 1993-04-15 | 1994-10-25 | Morita Tokyo Seisakusho:Kk | Dental diagnostic device with bactericidal water producing device |
| CN105542059A (en) * | 2015-11-25 | 2016-05-04 | 深圳市昌华生物医学工程有限公司 | Synthetic method of methyl methacrylate and N-vinyl pyrrolidone copolymer |
| CN108219066A (en) * | 2018-01-11 | 2018-06-29 | 东莞理工学院 | A kind of nanometer of povidone-iodine antibacterial dyestuff and preparation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| QINGGELE BORJIHAN等: "Controlled Engineering of Nano-Povidones for Efficient Iodine Recovery and Antibacterial Reutilization", 《ACS SUSTAINABLE CHEM. ENG.》, vol. 8, pages 11704 - 11712 * |
| TIANYI GAO等: "Povidone−Iodine-Based Polymeric Nanoparticles for Antibacteria Applications", 《ACS APPL. MATER. INTERFACES》, vol. 9, pages 25738 - 25746 * |
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