CN-117463306-B - Adsorption chromatographic material of technetium in radioactive waste liquid and preparation method thereof

CN117463306BCN 117463306 BCN117463306 BCN 117463306BCN-117463306-B

Abstract

The invention relates to an adsorption chromatographic material of technetium in radioactive waste liquid and a preparation method thereof, comprising the following steps of S1, exhausting air in pores of a silicon dioxide matrix, S2, uniformly mixing acetophenone, diethyl phthalate, vinyl pyridine and divinylbenzene, then adding an initiator azodiisobutyronitrile and an initiator V-40, uniformly mixing to obtain a mixed solution, S3, mixing the mixed solution and the silicon dioxide matrix under a vacuum condition, then recovering normal pressure, and then circulating for a plurality of times under the vacuum-normal pressure condition, finally recovering normal pressure, S4, continuously heating a reaction system after recovering normal pressure for a plurality of times, finally recovering normal temperature, and flushing for a plurality of times to obtain the adsorption chromatographic material. Compared with the prior art, the pyridine type weak-base anion exchange resin is directly obtained through copolymerization, the chloromethylation and amination processes in the traditional process are omitted, the process of resin synthesis is greatly simplified, and the adsorption effect on 99 Tc in radioactive waste liquid is good.

Inventors

LIU JIANPENG
GUO JIANFENG
Yang Buteng
ZHANG HANYU
CHAI SHIQUAN
JIN DONGKUI
XUE HONGPENG
JIN XIAOJUN
WU YAN

Assignees

中核四0四有限公司

Dates

Publication Date: 20260508
Application Date: 20230815

Claims (6)

1. The application of the adsorption chromatographic material in adsorbing technetium in radioactive waste liquid is characterized in that the preparation method of the adsorption chromatographic material comprises the following steps: s1, exhausting air in pores of a silicon dioxide matrix; s2, uniformly mixing acetophenone, diethyl phthalate, vinyl pyridine and divinylbenzene, and then adding an initiator azodiisobutyronitrile and an initiator V-40 to uniformly mix to obtain a mixed solution; S3, mixing the mixed solution obtained in the step S2 with the silicon dioxide matrix obtained in the step S1 under the vacuum condition, then recovering normal pressure, then circulating for a plurality of times under the vacuum-normal pressure condition, and finally recovering normal pressure; s4, continuously heating the reaction system recovered to normal pressure in the step S3 for a plurality of times, and finally recovering to normal temperature, and flushing for a plurality of times to obtain an adsorption chromatographic material; Wherein in the step S2, the volume ratio of acetophenone, diethyl phthalate, vinyl pyridine, divinylbenzene, initiator azobisisobutyronitrile and initiator V-40 is 22:15:9:2:1.6:1; In the step S4, three continuous heating is performed, wherein the temperature of the primary heating is 70 ℃, the time of the primary heating is 1 h, the temperature of the secondary heating is 80 ℃, the time of the secondary heating is 1 h, the temperature of the tertiary heating is 90 ℃, and the time of the tertiary heating is 10 h.
2. The use of an adsorption chromatography material according to claim 1 for adsorbing technetium in radioactive waste, wherein in step S2, the vinylpyridine is 4-vinylpyridine.
3. The use of an adsorption chromatography material according to claim 1 for adsorbing technetium from radioactive waste, wherein in step S3 the volume/mass ratio of mixed liquor to silica matrix is (50-55) mL 50 g.
4. The use of an adsorption chromatography material according to claim 1, wherein in step S3, the mixture is mixed with the silica matrix such that the mixture is substantially within the interstices of the silica matrix until no silica particles are bound together.
5. The use of an adsorption chromatography material according to claim 1 for adsorbing technetium from radioactive waste, wherein in step S3, the process is cycled at least three times under vacuum-normal pressure conditions to ensure an oxygen-free environment.
6. The use of an adsorption chromatography material according to claim 1 for adsorbing technetium from radioactive waste, wherein the heating rate is 10 ℃ per minute.

Description

Adsorption chromatographic material of technetium in radioactive waste liquid and preparation method thereof Technical Field The invention relates to the field of nuclide separation research in radioactive waste liquid, in particular to an adsorption chromatographic material of technetium in radioactive waste liquid and a preparation method thereof. Background The fission product 99 Tc in the radioactive waste liquid is a long-life radionuclide mainly derived from 235 U fission, occupies 6.03% of the total amount of all uranium fission products, is a radionuclide with half-life of 2.13×10 5 years, releases low-energy beta rays while decaying, is easy to migrate and diffuse in the environment, can be separated out for transmutation, can reduce the harm to the environment, and is one of targets of advanced spent fuel aftertreatment. Since 99 Tc usually exists in the form of anions of TcO 4- in the high-level radioactive waste liquid, when Tc is separated and adsorbed by adopting an ion exchange mode, the affinity of active groups on a separating material to TcO 4- is greater than that of anions in resin, so that Tc is separated from the solution. Ion exchange resins commonly used in the market today are almost exclusively spherical cross-linked copolymers. The synthesis of ion exchange resins can be divided in methods into addition polymerization type and polycondensation type. The largest amount of polyaddition ion exchange resins are currently used, with crosslinked polystyrene and crosslinked polyacrylic acid being the main materials. Most of ion exchange resins are synthesized by synthesizing cross-linked copolymer spheres by a suspension copolymerization method, introducing needed ion exchange groups through a certain chemical reaction, and the preparation process is complex. Only a few ion exchange resins are prepared by direct copolymerization of monomers bearing functional groups. Disclosure of Invention The invention aims to develop an ion exchange resin with simple preparation process and high adsorption efficiency and provides an adsorption chromatographic material for technetium in radioactive waste liquid and a preparation method thereof. The aim of the invention can be achieved by the following technical scheme: one of the technical schemes of the invention is to provide a preparation method of adsorption chromatographic material of technetium in radioactive waste liquid, which comprises the following steps: s1, exhausting air in pores of a silicon dioxide matrix; s2, uniformly mixing acetophenone, diethyl phthalate, vinyl pyridine and divinylbenzene, and then adding an initiator azodiisobutyronitrile and an initiator V-40 to uniformly mix to obtain a mixed solution; S3, mixing the mixed solution obtained in the step S2 with the silicon dioxide matrix obtained in the step S1 under the vacuum condition, then recovering normal pressure, then circulating for a plurality of times under the vacuum-normal pressure condition, and finally recovering normal pressure; and S4, continuously heating the reaction system recovered to normal pressure in the step S3 for a plurality of times, and finally recovering to normal temperature, and flushing for a plurality of times to obtain the adsorption chromatographic material. In some embodiments, in step S2, the vinylpyridine is 4-vinylpyridine. In some embodiments, in step S2, the volume ratio of acetophenone, diethyl phthalate, vinylpyridine, divinylbenzene, initiator Azobisisobutyronitrile (AIBN), and initiator V-40 is 22:15:9:2:1.6:1. In some embodiments, in step S3, the ratio of the mixed liquor to the silica matrix is (50-55) mL:50g. In some embodiments, in step S3, the mixed solution is mixed with the silica matrix such that the mixed solution fully enters the voids of the silica matrix until no silica particles adhere to form clusters. In some embodiments, at step S3, the vacuum-atmospheric conditions are cycled at least three times to ensure an oxygen-free environment. In some embodiments, in step S4, three consecutive heats are performed. In some embodiments, in step S4, the temperature of the primary heating is 70 ℃, the time of the primary heating is 1h, the temperature of the secondary heating is 80 ℃, the time of the secondary heating is 1h, the temperature of the tertiary heating is 90 ℃, and the time of the tertiary heating is 10h. In some embodiments, in step S4, the heating is at a ramp rate of 10℃per minute. The second technical scheme of the invention is to provide an adsorption chromatographic material of technetium in radioactive waste liquid, and the preparation method based on one of the technical schemes is provided. Compared with the prior art, the invention has the following beneficial effects: (1) The invention uses vinyl pyridine as monomer and divinylbenzene as cross-linking agent, and directly obtains pyridine type weak alkaline anion exchange resin through copolymerization reaction, thereby omitting chloromethylation and amination p