CN-117920159-B - Polybenzimidazole functionalized silicon-based resin and preparation method and application thereof

CN117920159BCN 117920159 BCN117920159 BCN 117920159BCN-117920159-B

Abstract

The application discloses a preparation method of polybenzimidazole functionalized silica-based resin, which comprises the following operation steps of S1, preparing polybenzimidazole, S2, preparing the polybenzimidazole functionalized silica-based resin, and S3, optimizing the polybenzimidazole functionalized silica-based resin by heat treatment. The application also provides the polybenzimidazole functionalized silicon-based resin prepared by the preparation method of the polybenzimidazole functionalized silicon-based resin and application of the polybenzimidazole functionalized silicon-based resin. The silicon-based resin provided by the application contains rich nitrogen sites, realizes high adsorption capacity and excellent selective separation of palladium ions under the condition of high acid, can be reused after elution, and effectively solves the problems of low adsorption capacity, poor selectivity, poor acid resistance and irradiation resistance stability and low reuse rate of the existing adsorption material under the condition of high radioactive waste liquid with extremely complex components and high radioactive environment.

Inventors

Jiang tianjiao
LI WENLONG
MA ZHILIANG
WEI YUEZHOU
XIE CHAO
NING SHUNYAN
Yin Xiangbiao
LUO CAIWU
CHEN LIFENG
WANG JI

Assignees

南华大学

Dates

Publication Date: 20260512
Application Date: 20240312

Claims (10)

1. The preparation method of the polybenzimidazole functionalized silica-based resin is characterized by comprising the following operation steps: S1, preparing polybenzimidazole, namely mixing polyphosphoric acid with 3,3', 4' -tetraminobiphenyl and malonic acid in a protective atmosphere, reacting at a certain temperature to obtain a solid product, filtering and washing the solid product to obtain solid powder, and removing impurities from the solid powder to obtain the polybenzimidazole; S2, preparing polybenzimidazole functional silicon-based resin, namely dissolving polybenzimidazole in an organic solvent to prepare a polybenzimidazole solution, immersing the polybenzimidazole solution into a silicon dioxide pore canal in a vacuum environment until the solvent is completely volatilized, and obtaining the polybenzimidazole functional silicon-based resin after vacuum impregnation; And S3, heat treatment is carried out on the optimized polybenzimidazole functionalized silicon-based resin, namely, the polybenzimidazole functionalized silicon-based resin is heat treated for a period of time at 120-300 ℃ to obtain the optimized polybenzimidazole functionalized silicon-based resin.
2. The preparation method of the polybenzimidazole functionalized silica-based resin according to claim 1, wherein the addition amount of polyphosphoric acid and 3,3', 4' -tetraminobiphenyl and malonic acid in the step S1 is 90-95 parts by mass, 3',4' -tetraminobiphenyl 3-5 parts and 3,3', 4' -tetraminobiphenyl 2-4 parts.
3. The preparation method of the polybenzimidazole functionalized silica-based resin according to claim 1, wherein the specific process of mixing the polyphosphoric acid, 3', 4' -tetraminobiphenyl and malonic acid in the step S1 is that a nitrogen pipe and an electric stirring device are connected with a three-neck flask which is dried, the polyphosphoric acid is added into the three-neck flask, the three-neck flask is placed into an oil bath pot, N 2 is introduced, the stirring device is started under the protection of nitrogen, the temperature is slowly increased to 60-85 ℃ for stirring and deoxidizing for 0.5-1.5 h, then the temperature is reduced to 20-35 ℃, then the feeding is performed, 3', 4' -tetraminobiphenyl is added, the stirring and the oxygen removal are performed at room temperature, the temperature is increased to 60-85 ℃, the heating is continued until the 3,3', 4' -tetraminobiphenyl is completely dissolved in a solvent, the room temperature is cooled, the malonic acid is added, and then the nitrogen is introduced for removing the oxygen at the room temperature.
4. The method for preparing the polybenzimidazole functionalized silica-based resin according to claim 3, wherein the reaction process in the step S1 is specifically heating under the condition of oil bath, so that the system is respectively reacted for 3-5 hours at 110-130 ℃, 7-9 hours at 150-160 ℃ and 11-13 hours at 200-220 ℃.
5. The preparation method of the polybenzimidazole functionalized silica-based resin according to claim 1, wherein the impurity removal process of the solid powder in the step S1 is specifically that the solid powder is soaked in an aqueous solution of 10-15% NaHCO 3 for 2-3 days to neutralize residual acid in the polymer, and finally the polymer is washed to be neutral by deionized water, and the obtained polymer is dried in a vacuum drying oven for 24-48 hours.
6. The preparation method of the polybenzimidazole functionalized silica-based resin according to any one of claims 1 to 5, wherein the polybenzimidazole and silica are added in the step S2 in an amount of 30 to 35 parts by mass of polybenzimidazole and 65 to 70 parts by mass of silica.
7. The preparation method of the polybenzimidazole functionalized silica-based resin according to any one of claims 1 to 5, wherein the polybenzimidazole solution in the step S2 is immersed into a silica pore canal, and the preparation method is characterized in that a certain amount of porous SiO 2 pellet carriers are firstly weighed into an eggplant-shaped flask, then a certain amount of polybenzimidazole prepared in the step S1 is weighed into a proper amount of organic solvent, the solvent is heated appropriately to accelerate the dissolution, the solvent is moved into the eggplant-shaped flask after the solvent is completely dissolved, finally the eggplant-shaped flask is fixed to a rotary evaporator, vacuum pumping is carried out until the air pressure in the flask is 20 to 50hPa, then inert gas is filled to restore normal pressure, the steps are circulated for 2 to 3 times, air in the flask is replaced, the rotating speed of the flask is kept at the normal temperature and the normal pressure for 1 to 2 hours, then standing is carried out for 2 to 4 hours, an oil bath is heated to 110 to 130 ℃, the rotating speed of the flask is kept at the 60 to 80rpm, a cooling water circulation device is opened while the heating is carried out, after the steps are completed, the vacuum pump is opened, and the polybenzimidazole is immersed into the silica pore canal in a slow pressure reducing mode.
8. The method for preparing a polybenzimidazole functionalized silica-based resin according to any one of claims 1 to 5, where the organic solvent in step S2 is N-methylpyrrolidone or dimethyl sulfoxide.
9. A polybenzimidazole functionalized silica-based resin prepared by the method of any one of claims 1 to 8.
10. An adsorption material for separating palladium from high level waste liquid, which is characterized by comprising the polybenzimidazole functionalized silica-based resin prepared by the preparation method according to any one of claims 1 to 8.

Description

Polybenzimidazole functionalized silicon-based resin and preparation method and application thereof Technical Field The application relates to the technical field of adsorption separation materials, in particular to polybenzimidazole functionalized silicon-based resin and a preparation method and application thereof. Background Palladium is an important member of platinum group metals (ruthenium, rhodium, palladium, osmium, iridium and platinum), the content of the palladium in the crust is less than 0.52ppb, the global reserve is estimated to be about 3220t, and the palladium is widely applied to the high-tip fields of automobile industry, petrochemical industry, electronic information industry, biological medicine and the like because the palladium has good chemical stability, corrosion resistance, thermal stability, catalytic property, high electrical conductivity, thermal conductivity and the like, and is an important raw material of modern industry. With the rapid development of the high and new technology industry, palladium has been increasingly used and the demand for palladium has been increasing. However, the platinum group metal resources in China are seriously deficient, the reserves are only 324t, and account for 0.2% of the global reserves, and the contradiction between supply and demand is prominent. Therefore, development of a technology for separating and recovering palladium from secondary resources is of great importance to palladium strategic resource supply. Currently, 430 nuclear power plants are running worldwide, producing large amounts of spent fuel each year, about 120000t spent fuel worldwide, and also growing rapidly at 7200t per year. Noble metal palladium is taken as one of main fission products of nuclear fuel 235 U or 239 Pu, the content is quite considerable, 1000t of fission Pd is expected to be stored in spent fuel in 2030, and the noble metal palladium is expected to become a substitute resource to meet the increasing demands. In addition, in the high level waste (HLLW) glass curing process, the presence of palladium increases the melting point of the glass and tends to form an independent phase, which results in non-uniformity of the glass matrix, affects the stability of the glass body, and increases the difficulty of the glass curing process and the risk of radioactive leakage during long-term storage. Therefore, the fission product palladium can be effectively separated and recycled from the high-level waste liquid, so that the strategic resource palladium can be recycled, the contradiction between supply and demand of palladium resources in China can be relieved, the negative influence of the palladium in the post-treatment process of spent fuel can be eliminated, the treatment difficulty of the high-level waste liquid is reduced, and the stability and safety of the high-level waste liquid glass solidification are improved. The main research methods for separating the fission product palladium include a coprecipitation method, a solvent extraction method, a membrane separation method, a biological method, an electrodeposition method, an adsorption method and the like. Compared with other separation methods, the solid-liquid adsorption method has the advantages of high adsorption efficiency, high selectivity, low cost, repeated use and the like, and the existing palladium adsorption material mainly comprises natural adsorbents such as zeolite, active carbon and the like, inorganic nano materials, framework materials and the like, and other inorganic and organic adsorbents. However, the materials have the defects of poor selectivity, low adsorption capacity and the like, for example, the adsorption capacity of nano Fe 3O4 particles is low and only 10.6mg/g, the adsorption capacity of UHMWPE-PMDA chelating resin on Pd (II) is obviously higher than that of other metal ions (Cu (II), zn (II), cr (II), fe (III), ni (II) and the like, the concentration of coexisting ions is far higher than that of Pd (II), and the maximum adsorption capacity is about 221.8mg/g, but the adsorption capacity of the adsorbent in high acid is poor. In the prior published literature, the maximum adsorption capacities of the novel heterocyclic polymers PS-MBO, PS-MBI and PS-MMBT on Pd (II) are 171.2mg/g, 138.8mg/g and 142.0mg/g respectively, but the adsorption effect and selectivity of the novel heterocyclic polymers are obviously deteriorated along with the increase of acidity, the maximum adsorption capacity of the UIO-66 on Pd under a 1mol/L nitric acid system is only 45mg/g, the selectivity is poor, and the extraction rate of the materials on Ag and Se is over 70 percent. Therefore, the research and development of the adsorption material with high palladium adsorption capacity, good selectivity, strong acid resistance and reusability under the condition of high acid is of great significance. Disclosure of Invention In order to solve the technical problems, the invention provides the polybenzim