Universal method for co-adsorbing perrhenate or pertechnetate by using cationic dye modified activated carbon

Abstract

The invention relates to a universal method for co-adsorbing perrhenate or pertechnetate by using cationic dye modified activated carbon, and belongs to the technical field of water treatment. In the system provided by the invention, the cationic dye modified activated carbon is used as an adsorbent of perrhenate or pertechnetate, and the cationic dye / activated carbon composite material realizes efficient removal of pollutants by co-adsorbing the perrhenate or pertechnetate in sewage. According to the invention, 12 activated carbon is used as a porous carrier, and after five different cationic dyes are respectively adsorbed, perrhenate radicals can be effectively adsorbed. Particularly, after methylene blue dye is adsorbed, perrhenic acid radicals can be quickly adsorbed within an extremely short time, and the adsorbent has the advantages of large adsorption capacity, good pH stability, high selectivity, good radiation resistance, low cost and the like, and can be applied to actual environmental sewage.

Description

Technical Field

[0001] The present invention relates to a general method for co-adsorbing perrhenate or pertechnetate using cationic dye-modified activated carbon, belonging to the technical field of water treatment. Background Art

[0002] The rapid development of the nuclear industry has generated a large amount of radioactive waste. 99 Tc is 235 produced with a yield as high as 6% in the fission reaction of 5 U and is one of the main components of nuclear waste. Its half-life is about 2.13×10 99 TcO4 - ), usually exists in the water environment in the form of pertechnetate ( 99 TcO4 - ). It is highly soluble (concentration 11.3 mol / L at 20 °C) and there is no natural substance to complex it, resulting in its extremely easy migration with the aqueous solution and entry into the food chain, posing great harm to the environment and human health. Therefore, 99 TcO4 - once released into the environment, it will become one of the most harmful radioactive pollutants to the environment. Due to - TcO4 - being radioactive, ReO4

[0003] with similar thermodynamic parameters, charge density and stereochemical structure is used in the laboratory for research on adsorption performance instead. Summary of the Invention

[0004] The technical problem solved by the present invention is to propose a general method for co-adsorbing perrhenate using cationic dye-modified activated carbon. The present invention uses activated carbon as a solid carrier and adsorbent, and the cationic dye provides positive potential adsorption sites, which can efficiently remove perrhenate in water. It solves the problems of poor removal effect of existing adsorption materials and cumbersome preparation processes.

[0005] To solve the above technical problems, the technical solution proposed by the present invention is as follows: A general method for co-adsorbing perrhenate or pertechnetate using activated carbon modified with cationic dyes, and the specific steps are as follows:

[0006] Prepare an aqueous solution of dye molecules with a concentration of 200 - 1000 ppm. The dye molecules are methylene blue (MB), rhodamine 6G (R6G), thioflavin T (THT), rhodamine B (RHB), tetrazolium blue chloride (TBT), and nitroblue tetrazolium chloride (NBT). Disperse the activated carbon into the aqueous solution of dye molecules, and place it on a three-dimensional shaker to shake for adsorption. After the activated carbon adsorbed with dye molecules is filtered and washed with pure water, it is placed in a vacuum oven for drying to obtain AC-Dye material. Then, disperse the AC-Dye into the aqueous solution of perrhenate or pertechnetate, and place it on a three-dimensional shaker to shake to complete the co-adsorption of perrhenate or pertechnetate.

[0007] Preferably, the 12 commercial activated carbons (AC1 - AC12) are, in order, ultra-high specific surface area activated carbon (UltraSorb-1), hierarchical porous activated carbon (PX15), hierarchically porous carbon (PWJ), high microporous activated carbon (PCV), high specific surface and high mesoporous carbon (PX16), macroporous carbon (PCD), carboxyl activated carbon (PC-S1X), carboxyl activated carbon (PC-A1X), hydrochloric acid-washed high specific surface carbon (PC-YS-1G), phosphoric acid powder activated carbon (PC-L1), nitrogen-doped activated carbon (PC-T7), high iodine activated carbon (y60s).

[0008] Preferably, among the twelve activated carbons, the ultra-high specific surface area activated carbon (UltraSorb-1) AC1 has the largest adsorption capacity for all six dyes.

[0009] Preferably, in step (1): Prepare an aqueous solution of dye molecules and an aqueous solution of perrhenate. The specific steps for preparing the aqueous solution of dye molecule methylene blue MB and the aqueous solution of perrhenate are to weigh a certain amount of dye molecules and perrhenate respectively, and dissolve them in water according to different ratios to prepare an aqueous solution of dye molecules with a concentration of 800 ppm and an aqueous solution of perrhenate with a concentration of 28 - 1000 ppm.

[0010] Step (2): Adsorption of dye molecules by activated carbon (UltraSorb-1) and its co-adsorption of perrhenate; for the adsorption of dye molecules by the activated carbon, the specific steps are to disperse the activated carbon into the aqueous solution of dye molecules, place it on a three-dimensional shaker and shake it constantly at a rate of 70 revolutions per minute for 6 hours to complete the adsorption; for the co-adsorption of perrhenate, the specific steps are to filter the activated carbon adsorbed with dye molecules, wash it with pure water, and then put it into a vacuum oven to dry at 80 °C for 12 hours to obtain the AC1-MB material. The AC1-MB is dispersed into the perrhenate aqueous solution at a solid-liquid ratio of 1 mg (AC) / mL, and placed on a three-dimensional shaker to shake for 2 minutes to complete the co-adsorption of perrhenate.

[0011] A general method for co-adsorbing perrhenate or pertechnetate using cationic dye-modified activated carbon, the specific steps are as follows

[0012] Step (1): Prepare aqueous solutions of dye molecules and perrhenate at different concentrations respectively;

[0013] Step (2): Disperse the activated carbon into the dye molecule solution for adsorption. After the adsorption is completed, detect the supernatant and dry the solid material;

[0014] Step (3): Disperse the dried material into the perrhenate aqueous solution for co-adsorption. After the adsorption is completed, detect the supernatant;

[0015] Step (4): Test the adsorption rate of the material for perrhenate, adsorption isotherm, influence of pH value on removal rate, influence of co-existing ions, influence of competitive anions, influence of solid-liquid ratio on removal rate, and cyclic stability respectively;

[0016] Step (5): Test the adsorption kinetics and adsorption isotherm of the material for perrhenate after irradiation with high-intensity β and γ rays respectively, and the maximum adsorption amount of the material for perrhenate after irradiation with β and γ rays of different intensities;

[0017] In Step (1), for the preparation of aqueous solutions of dye molecules and perrhenate at different concentrations, the specific method is to weigh a certain amount of dye molecules and sodium perrhenate respectively, and dissolve them in water according to different ratios to prepare an aqueous solution of dye molecules with a concentration of 200 - 1000 ppm and an aqueous solution of perrhenate with a concentration of 28 - 1000 ppm.

[0018] The adsorption by dispersing activated carbon into the dye molecule solution in step (2) is specifically as follows: 12 types of activated carbon are added to the 600 ppm aqueous solution of dye molecules at a solid-liquid ratio of 1 mg / mL, placed on a three-dimensional shaker, and constantly shaken at a rate of 70 revolutions per minute for 6 hours to complete the adsorption. The supernatant is quantitatively analyzed for dye molecules by a UV-Vis spectrophotometer (UV), and the adsorption material is placed in a vacuum oven at 80 °C for 12 hours for drying;

[0019] The co-adsorption by dispersing the dried material into the perrhenate aqueous solution in step (3) is specifically as follows: Weigh the mass of the obtained adsorption material, calculate the mass percentage of activated carbon according to the result measured by UV, and add AC-Dye to the 400 ppm perrhenate aqueous solution at a solid-liquid ratio of 1 mg (AC) / mL based on the mass of activated carbon. Constantly shake and adsorb at a rate of 70 revolutions per minute on a three-dimensional shaker for 6 hours. After the adsorption, quantitatively analyze the concentration of Re in the supernatant by inductively coupled plasma mass spectrometry (ICP-MS), and then convert the mass ratio of Re to perrhenate to obtain the actual adsorption amount of the material for perrhenate;

[0020] Preferably, in the process of co-adsorbing perrhenate in step (3), RHB has a multiplicative improvement in the effect of co-adsorbing perrhenate. However, compared with that, the activated carbon adsorbed with five dyes, namely MB, R6G, THT, TBT, and NBT, has a more obvious improvement.

[0021] Preferably, the four dye molecules, MB, R6G, TBT, and NBT, have good acid and alkali resistance properties and will not be washed out by acid / alkali after being adsorbed by AC1.

[0022] Preferably, MB is the dye molecule with the most cost advantage among the four dyes with obvious improvement in co-adsorption effect and good acid-base stability.

[0023] Preferably, AC1 is selected for adsorption at a solid-liquid ratio of 1 mg / mL by adding it to the 800 ppm MB aqueous solution for 6 hours, and then dried to obtain AC1-MB.

[0024] The adsorption rate in step (4) is specifically as follows: Add AC1-MB to the 400 ppm perrhenate solution at a solid-liquid ratio of 1 mg (AC) / mL and shake for adsorption. Detect the supernatant by ICP-MS at 1 s, 5 s, 10 s, 30 s, 60 s, 120 s, 300 s, 600 s, and 1200 s respectively;

[0025] Preferably, AC1-MB reaches the adsorption equilibrium for perrhenate at 120 s.

[0026] Regarding the adsorption isotherm described in step (4), the specific procedure is to add AC1-MB into perrhenate solutions at concentrations of 28, 40, 60, 100, 200, 400, 600, and 800 ppm with a solid-liquid ratio of 1 mg (AC) / mL, shake for adsorption, and after 2 minutes of adsorption, detect the supernatant using ICP-MS;

[0027] Regarding the influence of the pH value on the removal rate described in step (4), the specific procedure is to add AC1-MB into perrhenate solutions at a concentration of 100 ppm with a pH value ranging from 1 to 13 with a solid-liquid ratio of 1 mg (AC) / mL, shake for adsorption, and after 2 minutes of adsorption, detect the supernatant using ICP-MS;

[0028] Regarding the influence of coexisting ions described in step (4), the specific procedure is to add AC1-MB into a solution where both the coexisting anions (NO3 - 、SO4 2- 、ClO4 - 、PO4 3- 、CO3 2- 、Cl - )and perrhenate are both 0.4 mM, shake for adsorption, and after 2 minutes of adsorption, detect the supernatant using ICP-MS;

[0029] Regarding the influence of competitive anions described in step (4), the specific procedure is to add AC1-MB into 0.1 mM perrhenate solutions containing 0.1, 0.5, 1, 10, 100 mM NO3 - and 0.1, 0.5, 1, 10, 100, 600, 1000 mM SO4 2- respectively, shake for adsorption, and after 2 minutes of adsorption, detect the supernatant using ICP-MS;

[0030] Regarding the influence of the solid-liquid ratio on the removal rate described in step (4), the specific procedure is to add AC1-MB into 100 ppm perrhenate solutions containing 1 M HNO3 / NaOH with solid-liquid ratios of 1, 5, 10, 20, 30 mg (AC) / mL respectively, shake for adsorption, and after 2 minutes of adsorption, detect the supernatant using ICP-MS;

[0031] Regarding the cycle stability described in step (4), the specific procedure is to add AC1-MB into a 28 ppm perrhenate solution for adsorption, and after the adsorption is completed, add an equal amount of NaCl solution for desorption;

[0032] Preferably, the desorption conditions are 80 °C, 24 h, and the concentration of NaCl is 6 mol / L.

[0033] For the adsorption kinetics of perrhenate by the material after high-intensity irradiation in step (5), the steps are as follows: AC1-MB irradiated by 600 kGy β or γ rays is added to a 400 ppm perrhenate solution at a solid-liquid ratio of 1 mg (AC) / mL and shaken for adsorption. The supernatant is detected by ICP-MS at 1 s, 5 s, 10 s, 30 s, 1 min, 5 min, 10 min, 30 min, and 60 min respectively.

[0034] Preferably, AC1-MB after being irradiated by two kinds of high-intensity irradiation reaches the adsorption equilibrium for perrhenate at 30 min.

[0035] For the adsorption isotherm of perrhenate by the material after high-intensity irradiation in step (5), the steps are as follows: AC1-MB irradiated by 600 kGy β or γ rays is added to 28, 40, 60, 100, 200, 300, 400, 600 ppm perrhenate solutions at a solid-liquid ratio of 1 mg (AC) / mL and shaken for adsorption. The supernatant is detected by ICP-MS after adsorption for 30 min.

[0036] For testing the maximum adsorption capacity of the material for perrhenate after being irradiated by β and γ rays with different intensities in step (5), the specific steps are as follows: AC1-MB irradiated by 200, 400, 600 kGy β or γ rays is added to a 400 ppm perrhenate solution at a solid-liquid ratio of 1 mg (AC) / mL and shaken for adsorption. The supernatant is detected by ICP-MS after adsorption for 30 min.

[0037] Advantages of the present invention:

[0038] The present invention provides a method for co-adsorbing perrhenate using activated carbon as a solid carrier and adsorbent and a material providing positive adsorption potential adsorption sites by cationic dyes, which has a good removal effect. The results show that compared with other perrhenate removal materials in the prior art, AC1-MB has a faster adsorption rate and good adsorption capacity, has a good removal rate for perrhenate in a wide pH range of 3 - 10, and NO3 - 、SO4 2- 、ClO4 - 、PO4 3- 、CO3 2- 、Cl - Plasma will not affect the removal rate in the presence, and the removal rate does not decrease significantly after five-cycle experiments, and it also has excellent radiation resistance.

[0039] It can be seen from Example 3 that the adsorption kinetic curve of AC1-MB for perrhenate Figure 8 , and the adsorption equilibrium time is 120 s. The maximum adsorption capacity for perrhenate is shown in Figure 9 , which is 372 mg / g. When the initial concentration of perrhenate is 400 ppm, the adsorption capacity of AC1-MB for perrhenate is 350 mg / g.

[0040] The pH stability of AC1-MB for adsorbing perrhenate is shown in Figure 10 , and the removal rate of AC1-MB for perrhenate is above 97% in the pH range of 3-10.

[0041] The anti-interference ion selectivity of AC1-MB for adsorbing perrhenate is shown in Figure 11 , and the coexistence of several ions has almost no effect on the selective removal of perrhenate by AC1-MB, and the removal rate remains above 99%.

[0042] The competitive ion stability of AC1-MB for adsorbing perrhenate is shown in Figure 12 , when the concentration of NO3 - reaches 100 times that of perrhenate, the removal rate of AC1-MB for perrhenate still exceeds 90%, and when it reaches 1000 times, it drops to 50%. When the concentration of SO4 2- reaches 10000 times that of perrhenate, AC1-MB still has a 94% removal rate for perrhenate.

[0043] The effect of the solid-liquid ratio of AC1-MB on the removal rate of perrhenate under the conditions of 1 M HNO3 / NaOH is shown in Figure 13 , in the perrhenate solution containing 1 M HNO3, when the solid-liquid ratio reaches 30:1, the removal rate of AC1-MB for perrhenate reaches 84%. In the perrhenate solution containing 1 M NaOH, when the solid-liquid ratio reaches 20:1, the removal rate of AC1-MB for perrhenate reaches 72%.

[0044] The cyclic stability of AC1-MB for perrhenate is shown in Figure 14 , and the removal ability of AC1-MB for perrhenate remains stable within five cycles.

[0045] The adsorption kinetic curve of AC1-MB for perrhenate after being irradiated by 600 kGy β or γ rays is shown in Figure 15 , and the adsorption equilibrium time is 30 min. The maximum adsorption capacity for perrhenate after being irradiated by 600 kGy β or γ rays is shown in Figure 16The maximum adsorption capacities for perrhenate were 344 and 353 mg / g respectively. When the initial concentration of perrhenate was 400 ppm, the adsorption capacities of AC1-MB after being irradiated by two kinds of rays for perrhenate were 337 and 346 mg / g respectively.

[0046] The adsorption capacities of AC1-MB irradiated by β or γ rays with different intensities in 400 ppm perrhenate solution are shown in Figure 17 , the adsorption capacities of AC1-MB irradiated by 200, 400, 600 kGy β rays for perrhenate were 344, 334, 349 mg / g respectively. After being irradiated by 200, 400, 600 kGy γ rays, the adsorption capacities of AC1-MB for perrhenate were 358, 363, 356 mg / g respectively.

[0047] AC1 directly adsorbs perrhenate, and the adsorption isotherm is shown in Figure 18 , and the maximum adsorption capacity is 25.5 mg / g

[0048] When the dye molecules are changed to poly(diallyldimethylammonium chloride) and polyethyleneimine polymers for co-adsorption, the adsorption capacities for perrhenate are shown in Figure 19 , which are 46 and 29 mg / g respectively, 1.8 and 1.13 times that of AC1; when changed to acidified melamine molecules, according to the increase of acidification degree, the adsorption effect on perrhenate also increases significantly. After AC1 adsorbs melamine acidified by 0, 0.5, 1, 2, 3 M hydrochloric acid, the adsorption capacities for perrhenate are shown in Figure 20 , which are 27, 61, 75, 66, 72 mg / g respectively, 1.05, 2.39, 2.94, 2.59, 2.82 times that of AC1; when changed to small molecules such as guanidine hydrochloride, guanidine hydrobromide or triaminoguanidine hydrochloride for co-adsorption, the adsorption capacities for perrhenate are shown in Figure 21 , which are 41, 40 and 35 mg / g respectively, 1.6, 1.57 and 1.37 times that of AC1. Description of the Drawings

[0049] The present invention will be further described below with reference to the drawings.

[0050] Figure 1 is a schematic diagram of the simulation of co-adsorbing perrhenate after activated carbon adsorbs cationic dyes;

[0051] Figure 2 is the structural diagram of six dye molecules;

[0052] Figure 3It is the UV-visible spectra and standard curve graphs of six dye molecules, methylene blue (a, b), rhodamine 6G (c, d), thioflavin T (e, f), rhodamine B (g, h), nitroblue tetrazolium chloride (i, j), and nitrotetrazolium blue chloride (k, l);

[0053] Figure 4 It is a physical comparison graph of the supernatant after 12 kinds of activated carbon adsorbed 600 ppm dye molecules, methylene blue (a), rhodamine 6G (b), thioflavin T (c), rhodamine B (d), nitroblue tetrazolium chloride (e), nitrotetrazolium blue chloride (f), and the UV-visible spectra graphs of nitroblue tetrazolium chloride (f) and nitrotetrazolium blue chloride (g);

[0054] Figure 5 It is the co-adsorption effect graph of activated carbon adsorbed different concentrations of dyes on perrhenate;

[0055] Figure 6 It is the physical graph and retention rate graph (f) of five dye molecule solutions of 600 ppm soaked for 6 hours under the conditions of pH 2, 6, 8, and 12, methylene blue (a), rhodamine 6G (b), thioflavin T (c), nitroblue tetrazolium chloride (d), nitrotetrazolium blue chloride (e);

[0056] Figure 7 It is the physical and UV-visible analysis spectra graphs of AC1 adsorbed with 600 ppm of four dye molecules soaked for 6 hours under the conditions of pH 2, 6, 8, and 12, methylene blue (a, b), rhodamine 6G (c, d), nitroblue tetrazolium chloride (e, f), nitrotetrazolium blue chloride (g, h);

[0057] Figure 8 It is the adsorption kinetics graph of AC1-MB on perrhenate;

[0058] Figure 9 It is the adsorption isotherm graph of AC1-MB on perrhenate;

[0059] Figure 10 It is the adsorption performance graph of AC1-MB on perrhenate at different pH values;

[0060] Figure 11 It is the adsorption selectivity graph of AC1-MB on perrhenate in the presence of different anions;

[0061] Figure 12 It is the adsorption effect graph of AC1-MB on perrhenate in the presence of excessive competitive ions, NO3 - (a), SO4 2- (b);

[0062] Figure 13Removal effect diagrams of AC1-MB at different solid-liquid ratios in perrhenate solutions of 1 M HNO3 (a) and NaOH (b);

[0063] Figure 14 Cyclic desorption diagram of AC1-MB for perrhenate;

[0064] Figure 15 Adsorption kinetics diagram of AC1-MB for perrhenate after being irradiated by 600 kGy β or γ rays;

[0065] Figure 16 Adsorption isotherm diagram of AC1-MB for perrhenate after being irradiated by 600 kGy β or γ rays;

[0066] Figure 17 Maximum adsorption capacity diagrams of AC1-MB for perrhenate after being irradiated by 200, 400, and 600 kGy β or γ rays respectively;

[0067] Figure 18 Adsorption isotherm of AC1 for perrhenate;

[0068] Figure 19 Adsorption amounts of AC1 for perrhenate after adsorbing polydiallyldimethylammonium chloride or polyethyleneimine;

[0069] Figure 20 Adsorption amounts of AC1 for perrhenate after adsorbing acidified melamine;

[0070] Figure 21 Adsorption amounts of AC1 for perrhenate after adsorbing guanidine hydrochloride, guanidine hydrobromide, or triaminoguanidine hydrochloride. Detailed implementation manners

[0071] Example 1

[0072] Aqueous solutions of dye molecules (MB, R6G, THT, RHB, TBT, NBT) at 600 ppm were prepared respectively. The dye molecules are as Figure 2 shown. Twelve kinds of activated carbons (Table 1) were added to the aqueous solutions of dye molecules at a solid-liquid ratio of 1 mg / mL respectively, and placed on a three-dimensional shaker to shake constantly at a rate of 70 revolutions per minute for 12 hours to complete adsorption. The aqueous solutions of dye molecules after adsorption were quantitatively analyzed by colorimetry and ultraviolet-visible spectrophotometry as seen in Figure 4 , and the adsorption amounts of the twelve kinds of activated carbons for the six dye molecules are shown in Table 2. AC1 (UltraSorb-1) has the highest adsorption amount for the six dye molecules. Therefore, AC1 was selected for subsequent co-adsorption tests of perrhenate.

[0073] Prepare aqueous solutions of dye molecules (MB, R6G, THT, RHB, TBT, NBT) at concentrations of 200, 400, 600, 800, and 1000 ppm respectively. Add AC1 to the aqueous dye solutions at a solid-liquid ratio of 1 mg / mL, place them on a three-dimensional shaker, and shake them constantly at a rate of 70 revolutions per minute for 12 hours to complete the adsorption. Use a UV-visible spectrophotometer to measure the adsorption amounts of AC1 for different dyes at different concentrations as shown in Table 3. After washing the AC1 adsorbed with dyes with water, put it into a vacuum oven and dry it under the conditions of 80 °C for 12 h to obtain AC1-Dye materials adsorbed with different concentrations of dyes.

[0074] Based on the data measured by the UV-visible spectrophotometer, calculate the mass ratio of AC1 in AC1-Dye. Add the AC1-Dye material to a 400 ppm perrhenate solution at a solid-liquid ratio of 1 mg (AC) / mL for adsorption. After the adsorbed solution is filtered through a nylon filter head with a pore size of 0.22 μm, use ICP-MS to detect the concentration of Re in the supernatant, and then calculate the mass ratio of Re to perrhenate to obtain the adsorption results for perrhenate as Figure 5 shown. Except for RHB, the other five dyes have a very large promotion effect on the co-adsorption of perrhenate, and the co-adsorption amounts of AC1 adsorbed with 800 and 1000 ppm MB for perrhenate are almost the same.

[0075] Immerse the five dye molecules with obvious promotion effects (MB, R6G, THT, TBT, NBT) in solutions with pH values of 2, 6, 8, and 12 for 6 hours respectively. The results are as Figure 6 shown. THT is completely decomposed at pH = 12. Then immerse AC1 adsorbed with 600 ppm of the other four dye molecules in solutions with pH values of 2, 6, 8, and 12 for 6 hours. No dye is detected in the supernatant by UV-visible analysis spectrophotometer ( Figure 7 ). Among the five dyes (MB, R6G, THT, TBT, NBT) that have a promotion effect on the co-adsorption effect, THT is unstable under alkaline conditions. Among the remaining four dye molecules with good acid and alkali resistance and obvious promotion effects on the adsorption of perrhenate, it can be concluded from Table 4 that MB has an obvious cost advantage. Therefore, AC1 adsorbed with 800 ppm of MB is selected for the co-adsorption perrhenate test.

[0076] Table 1. Types and basic parameters of activated carbon

[0077]

[0078] Table 2. Adsorption amounts of 12 kinds of activated carbon for dyes in six dye molecule solutions at 600 ppm

[0079]

[0080] Table 3. Adsorption capacity of AC1 for dyes in dye molecule solutions with different concentrations

[0081]

[0082] Table 4. Comparison table of dye molecule costs

[0083]

[0084] Example 2

[0085] Dissolve 4 mg of MB in 5 mL of water to prepare an 800 ppm MB aqueous solution. Weigh 5 mg of AC1 and disperse it into the above MB aqueous solution. Place it on a three-dimensional shaker and shake it constantly at a rate of 70 revolutions per minute for 6 hours to complete the adsorption. Take the supernatant, detect the remaining MB concentration with a UV-visible spectrophotometer, calculate the mass of MB adsorbed by AC1, and thus calculate that the actual mass ratio of AC1 in AC1-MB is 0.566.

[0086] Wash the AC1 adsorbed with MB three times with water and then put it into a vacuum oven to dry at 80 °C for 12 h to obtain the adsorbent AC1-MB.

[0087] Example 3

[0088] Considering that AC1-MB has good adsorption capacity, a series of adsorption performance tests were carried out in this example. The solid mass in all solid-liquid ratios in the following tests is based on the mass of AC1 in AC1-MB for adsorption.

[0089] Add the AC1-MB prepared in Example 2 to the perrhenate solution of 400 ppm at a solid-liquid ratio of 1 mg (AC) / mL, and shake it constantly at a rate of 70 revolutions per minute on a three-dimensional shaker for adsorption. Detect the concentration of Re in the supernatant at 1 s, 5 s, 10 s, 30 s, 60 s, 300 s, 600 s, and 1200 s respectively with ICP-MS, and then convert the mass ratio of Re to perrhenate to obtain the adsorption kinetic curve of AC1-MB for perrhenate as shown in Figure 8 , and the adsorption equilibrium time is 120 s.

[0090] Add AC1-MB to the perrhenate solutions of 28, 40, 60, 100, 200, 400, 600, and 800 ppm at a ratio of 1 mg (AC) / mL, and shake it constantly at a rate of 70 revolutions per minute on a three-dimensional shaker for 2 min to complete the adsorption. Detect the concentration of Re in the supernatant with ICP-MS, and then convert the mass ratio of Re to perrhenate to obtain the adsorption isotherm of AC1-MB for perrhenate as shown inFigure 9 The maximum adsorption capacity for perrhenate is 372 mg / g. When the initial concentration of perrhenate is 400 ppm, the adsorption capacity of AC1-MB for perrhenate is 350 mg / g.

[0091] AC1-MB was added to perrhenate solutions with a concentration of 100 ppm and a pH ranging from 1 to 13 at a solid-liquid ratio of 1 mg (AC) / mL, and shaken constantly at a rate of 70 revolutions per minute on a three-dimensional shaker for 2 min to complete the adsorption. The concentration of Re in the supernatant was detected by ICP-MS, and then the mass ratio of Re to perrhenate was converted to obtain the pH stability of AC1-MB for adsorbing perrhenate as shown in Figure 10 , and the removal rate of perrhenate by AC1-MB was above 97% in the pH range of 3 - 10.

[0092] AC1-MB was added to solutions in which the coexisting ions (NO3 - / SO4 2 / ClO4 - / PO4 3- / CO3 2- / Cl - ) and perrhenate were both 0.4 mM at a solid-liquid ratio of 1 mg (AC) / mL, and shaken constantly at a rate of 70 revolutions per minute on a three-dimensional shaker for 2 min to complete the adsorption. The concentration of Re in the supernatant was detected by ICP-MS, and then the mass ratio of Re to perrhenate was converted to obtain the anti-interference ion selectivity of AC1-MB for adsorbing perrhenate as shown in Figure 11 , and the coexistence of several ions had almost no effect on the selective removal of perrhenate by AC1-MB, and the removal rate remained above 99%.

[0093] AC1-MB was added to 0.1 mM perrhenate solutions containing 0.1, 0.5, 1, 10, 100 mM NO3 - and 0.1, 0.5, 1, 10, 100, 600, 1000 mM SO4 2- at a solid-liquid ratio of 1 mg (AC) / mL, and shaken constantly at a rate of 70 revolutions per minute on a three-dimensional shaker for 2 min to complete the adsorption. The concentration of Re in the supernatant was detected by ICP-MS, and then the mass ratio of Re to perrhenate was converted to obtain the competitive ion stability of AC1-MB for adsorbing perrhenate as shown in Figure 12 , when the concentration of NO3 - was 100 times that of perrhenate, the removal rate of perrhenate by AC1-MB was still over 90%, and when it reached 1000 times, it dropped to 50%. For SO4 2-When the concentration is 10,000 times that of perrhenate, AC1-MB still has a 94% removal rate for perrhenate.

[0094] AC1-MB was added to a 100 ppm perrhenate solution containing 1 M HNO3 / NaOH at solid-liquid ratios of 1, 5, 10, 20, and 30 mg (AC) / mL, and shaken constantly at a rate of 70 revolutions per minute on a three-dimensional shaker for 2 min to complete adsorption. The concentration of Re in the supernatant was detected by ICP-MS, and the mass ratio of Re to perrhenate was calculated. The effect of the solid-liquid ratio of AC1-MB on the removal rate of perrhenate under the condition of 1 M HNO3 / NaOH is shown in Figure 13 , in the perrhenate solution containing 1 M HNO3, the removal rate of AC1-MB for perrhenate reached 84% when the solid-liquid ratio reached 30:1, and in the perrhenate solution containing 1 M NaOH, the removal rate of AC1-MB for perrhenate reached 72% when the solid-liquid ratio reached 20:1.

[0095] AC1-MB was added to a 28 ppm perrhenate solution at a ratio of 1 mg (AC) / mL, and shaken constantly at a rate of 70 revolutions per minute on a three-dimensional shaker for 2 min to complete adsorption. Then, an equal volume of 6 M NaCl solution was added and shaken at 80 °C for 24 h for desorption. The concentration of Re in the supernatant was detected by ICP-MS, and the mass ratio of Re to perrhenate was calculated. The cyclic stability of AC1-MB for perrhenate is shown in Figure 14 , the removal ability of AC1-MB for perrhenate remained stable within five cycles.

[0096] AC1-MB irradiated by 600 kGy β or γ rays was added to a 400 ppm perrhenate solution at a solid-liquid ratio of 1 mg (AC) / mL and shaken for adsorption. The concentration of Re in the supernatant was detected by ICP-MS at 1 s, 5 s, 10 s, 30 s, 1 min, 5 min, 10 min, 30 min, and 60 min respectively, and the mass ratio of Re to perrhenate was calculated. The adsorption kinetic curve of AC1-MB irradiated by high-intensity rays for perrhenate is shown in Figure 15 , and the adsorption equilibrium time was 30 min.

[0097] AC1-MB irradiated with 600 kGy of β or γ rays was added to perrhenate solutions at 28, 40, 60, 100, 200, 300, 400, and 600 ppm at a solid-liquid ratio of 1 mg (AC) / mL, and adsorption was completed by constant shaking at 70 revolutions per minute on a three-dimensional shaker for 30 min. The concentration of Re in the supernatant was detected by ICP-MS, and the mass ratio of Re to perrhenate was calculated to obtain the adsorption isotherm of AC1-MB irradiated with high-intensity rays for perrhenate as shown in Figure 16 , the maximum adsorption capacities of AC1-MB for perrhenate after irradiation with 600 kGy of β or γ rays were 344 and 353 mg / g, respectively. When the initial concentration of perrhenate was 400 ppm, the adsorption capacities for perrhenate were 337 and 346 mg / g, respectively.

[0098] AC1-MB irradiated with 200, 400, and 600 kGy of β or γ rays was added to a perrhenate solution at 400 at a solid-liquid ratio of 1 mg (AC) / mL, and adsorption was completed by constant shaking at 70 revolutions per minute on a three-dimensional shaker for 30 min. The concentration of Re in the supernatant was detected by ICP-MS, and the mass ratio of Re to perrhenate was calculated to obtain the maximum adsorption capacity of AC1-MB for perrhenate after irradiation with different intensities of β or γ rays as shown in Figure 17 , after irradiation with 200, 400, and 600 kGy of β rays, the adsorption capacities of AC1-MB for perrhenate were 344, 334, and 349 mg / g, respectively. After irradiation with 200, 400, and 600 kGy of γ rays, the adsorption capacities of AC1-MB for perrhenate were 358, 363, and 356 mg / g, respectively.

[0099] Comparative Example 1

[0100] Direct adsorption of perrhenate by activated carbon: AC1 was added to aqueous perrhenate solutions at 10, 15, 28, 40, 60, 80, and 100 ppm at a solid-liquid ratio of 1 mg / mL, and adsorption was completed by constant shaking at 70 revolutions per minute on a three-dimensional shaker for 24 h. The concentration of Re in the supernatant was detected by ICP-MS, and the mass ratio of Re to perrhenate was calculated to obtain the adsorption isotherm of AC1 for perrhenate as shown in Figure 18 , the maximum adsorption capacity of AC1 for perrhenate was 25.5 mg / g.

[0101] Comparative Example 2

[0102] Effect of polymers on the co-adsorption of perrhenate: Aqueous solutions of polymers poly(diallyldimethylammonium chloride) (PDA) and polyethyleneimine (PEI) with a concentration of 1000 ppm were respectively prepared. AC1 was added to the two polymer solutions at a solid-liquid ratio of 1 mg / mL, and the adsorption was completed by constant shaking at a rate of 70 revolutions per minute on a three-dimensional shaker for 6 h. After washing AC1-PDA / PEI three times with water, it was placed in a vacuum oven and dried at 80 °C for 12 h. The dried AC1-PDA / PEI was dispersed in an aqueous perrhenate solution with a concentration of 400 ppm at a solid-liquid ratio of 1 mg / mL, and shaken constantly at a rate of 70 revolutions per minute on a three-dimensional shaker for 6 h. The concentration of Re in the supernatant was detected by ICP-MS, and the mass ratio of Re to perrhenate was calculated to obtain the adsorption amount of perrhenate after AC1 adsorbed poly(diallyldimethylammonium chloride) or polyethyleneimine, as shown in Figure 19 , which were 46 and 29 mg / g respectively.

[0103] Comparative Example 3

[0104] Effect of melamine on the co-adsorption of perrhenate: An aqueous solution of melamine (MEL) with a concentration of 1000 ppm was prepared and mixed with equal volumes of 0, 1, 2, 4, and 6 M hydrochloric acid (HCl) solutions respectively. The reaction was carried out by constant shaking at a rate of 70 revolutions per minute on a three-dimensional shaker for 6 h to obtain melamine solutions acidified with 0, 0.5, 1, 2, and 3 M hydrochloric acid respectively. AC1 was added to each of them at a solid-liquid ratio of 1 mg / mL and shaken continuously for 6 h to complete the adsorption. After washing the materials three times with water, they were placed in a vacuum oven and dried at 80 °C for 12 h. The dried AC1-MEL (0, 0.5, 1, 2, 3) was dispersed in an aqueous perrhenate solution with a concentration of 400 ppm at a solid-liquid ratio of 1 mg / mL, and shaken constantly at a rate of 70 revolutions per minute on a three-dimensional shaker for 6 h. The concentration of Re in the supernatant was detected by ICP-MS, and the mass ratio of Re to perrhenate was calculated to obtain the adsorption amount of perrhenate after AC1 adsorbed melamine acidified with different concentrations, as shown in Figure 20 , and the adsorption amounts of perrhenate after AC1 adsorbed melamine acidified with 0, 0.5, 1, 2, and 3 M hydrochloric acid were 27, 61, 75, 66, and 72 mg / g respectively.

[0105] Comparative Example 4

[0106] Effect of small molecules on the co-adsorption of perrhenate: Aqueous solutions of small molecules of guanidine hydrochloride (GHCl), guanidine hydrobromide (GHBr), and triaminoguanidine hydrochloride (THCl) with a concentration of 1000 ppm were prepared respectively. AC1 was added to the three small molecule solutions at a solid-liquid ratio of 1 mg / mL, and the adsorption was completed by constant shaking at a rate of 70 revolutions per minute on a three-dimensional shaker for 24 h. After washing AC1-GHCl / GHBr / THCl three times with water, it was placed in a vacuum oven and dried at 80 °C for 12 h. The dried AC1-GHCl / GHBr / THCl was dispersed in an aqueous solution of perrhenate with a concentration of 200 ppm at a solid-liquid ratio of 1 mg / mL, and shaken constantly at a rate of 70 revolutions per minute on a three-dimensional shaker for 24 h. The concentration of Re in the supernatant was detected by ICP-MS, and the mass ratio of Re to perrhenate was calculated. The adsorption amounts of perrhenate after AC1 adsorbed guanidine hydrochloride, guanidine hydrobromide, and triaminoguanidine hydrochloride are shown in Figure 21 , which are 41, 40, and 35 mg / g respectively.

Claims

1. A general method for co-adsorbing perrhenate or pertechnetate using cationic dye-modified activated carbon, characterized in that, The specific steps are as follows: Prepare an aqueous solution of dye molecules with a concentration of 200 - 1000 ppm. The dye molecules are methylene blue MB, rhodamine 6G (R6G), thioflavin T (THT), tetrazolium blue chloride TBT, and nitroblue tetrazolium chloride NBT. Disperse activated carbon into the aqueous solution of dye molecules and place it on a three-dimensional shaker to complete the adsorption by shaking. After filtering and washing the activated carbon adsorbed with dye molecules with pure water, put it into a vacuum oven for drying to obtain the AC-Dye material. Then disperse the AC-Dye into an aqueous solution of perrhenate or pertechnetate and place it on a three-dimensional shaker to complete the co-adsorption of perrhenate or pertechnetate.

2. The universal method for co-adsorbing perrhenate or pertechnetate using cationic dye-modified activated carbon according to claim 1, characterized in that, The 12 commercial activated carbons (AC1 - AC12) are, in order, ultra-high specific surface area activated carbon AC1 (UltraSorb-1), hierarchical porous activated carbon (PX15), hierarchically porous carbon (PWJ), high microporous activated carbon (PCV), high specific surface and high mesoporous carbon (PX16), macroporous carbon (PCD), carboxyl-activated carbon (PC-S1X), carboxyl-activated carbon (PC-A1X), hydrochloric acid-washed high specific surface carbon (PC-YS-1G), phosphoric acid powder activated carbon (PC-L1), nitrogen-doped activated carbon (PC-T7), high iodine activated carbon (y60s).

3. The universal method for co-adsorbing perrhenate or pertechnetate by using cationic dye-modified activated carbon according to claim 2, characterized in that, Among the twelve activated carbons, the ultra-high specific surface area activated carbon (UltraSorb-1) AC1 has the largest adsorption capacity for the five dyes.

4. The general method for co-adsorbing perrhenate or pertechnetate using activated carbon modified with cationic dyes according to claim 1, the specific steps are as follows: Step (1): Prepare an aqueous solution of dye molecules and an aqueous solution of perrhenate. The specific steps for preparing the aqueous solution of dye molecules and the aqueous solution of perrhenate are to weigh a certain amount of dye molecules and perrhenate salts respectively, dissolve them in water according to different ratios to prepare an aqueous solution of dye molecules with a concentration of 200 - 1000 ppm and an aqueous solution of perrhenate with a concentration of 28 - 1000 ppm. Step (2): Adsorption of dye molecules by activated carbon and its co-adsorption of perrhenate. The specific steps for the adsorption of dye molecules by activated carbon are to disperse activated carbon into the aqueous solution of dye molecules and place it on a three-dimensional shaker to complete the adsorption by shaking. The specific steps for the co-adsorption of perrhenate are to filter and wash the activated carbon adsorbed with dye molecules with pure water, put it into a vacuum oven for drying to obtain the AC-Dye material, and then disperse the AC-Dye into the aqueous solution of perrhenate and place it on a three-dimensional shaker to complete the co-adsorption of perrhenate.

5. The general method for co-adsorbing perrhenate or pertechnetate using activated carbon modified with cationic dyes according to claim 1, the specific steps are as follows: Step (1): Prepare an aqueous solution of dye molecules and an aqueous solution of perrhenate. The specific steps for preparing the aqueous solution of methylene blue MB dye molecules and the aqueous solution of perrhenate are to weigh a certain amount of dye molecules and perrhenate salts respectively, dissolve them in water according to different ratios to prepare an aqueous solution of dye molecules with a concentration of 800 ppm and an aqueous solution of perrhenate with a concentration of 28 - 1000 ppm. Step (2): Adsorption of dye molecules by activated carbon AC1 (UltraSorb-1) and its co-adsorption of perrhenate ions; for the adsorption of dye molecules by the activated carbon, the specific steps are to disperse the activated carbon into an aqueous solution of dye molecules, place it on a three-dimensional shaker and shake it constantly at a rate of 70 revolutions per minute for 6 hours to complete the adsorption; for the co-adsorption of perrhenate ions, the specific steps are to filter the activated carbon adsorbed with dye molecules, wash it with pure water, and then put it into a vacuum oven at 80 °C for drying for 12 hours to obtain the AC1-MB material. The AC1-MB material is dispersed into an aqueous solution of perrhenate ions at a solid-liquid ratio of 1 mg (AC) / mL, and placed on a three-dimensional shaker and shaken for 2 minutes to complete the co-adsorption of perrhenate ions.

6. The general method for co-adsorbing perrhenate or pertechnetate by using cationic dye-modified activated carbon according to claim 5, characterized in that, The AC1-MB material has an ultra-fast adsorption rate for perrhenate ions, can reach the adsorption equilibrium within an extremely short time of 120 s, and has a good adsorption capacity.

7. The general method for co-adsorbing perrhenate or pertechnetate using cationic dye-modified activated carbon according to claim 5, characterized in that, The AC1-MB material can have a high removal rate for perrhenate ions within the pH range of 3 - 10.

8. The general method for co-adsorbing perrhenate or pertechnetate using cationic dye-modified activated carbon according to claim 5, characterized in that, The described AC1-MB material has good selectivity for perrhenate ions in the coexistence of NO3 - , SO4 2- , ClO4 - , PO4 3- , CO3 2- , Cl - ions; it also has good removal ability in the presence of high concentrations of NO3 - or SO4 2- ; the described AC1-MB material can improve its removal rate of perrhenate ions under 1 M HNO3 / NaOH conditions by increasing its solid-liquid ratio relative to the solution.

9. The general method for co-adsorbing perrhenate or pertechnetate using cationic dye-modified activated carbon according to claim 5, characterized in that, The AC1-MB material still has a good ability to remove perrhenate ions after multiple adsorption and desorption processes; the AC1-MB material still has a good removal effect after being irradiated with high-intensity radiation.

10. The universal method for co-adsorbing perrhenate or pertechnetate by using cationic dye-modified activated carbon according to claim 5, characterized in that, Replacing the dye molecules with polymers such as poly(diallyldimethylammonium chloride) and polyethyleneimine, acidified melamine, small molecules such as guanidine hydrochloride, guanidine hydrobromide, and triaminoguanidine hydrochloride will significantly improve the co-adsorption.

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