Ce (Ⅳ) nitrato complexes were adsorbed on two anion exchangers based on polyvinyl pyridine (PVP) and quatemized PVP incorporated into porous silica matrix. The effect of nitric acid concentration (0.5~6 mol...Ce (Ⅳ) nitrato complexes were adsorbed on two anion exchangers based on polyvinyl pyridine (PVP) and quatemized PVP incorporated into porous silica matrix. The effect of nitric acid concentration (0.5~6 mol·L^-1) and temperature (278 ~318 K) on Ce( Ⅳ ) sorption efficiency was investigated. Sorption increased with increasing nitric acid concentration, indicating that [Ce(NO3)6]^2- complex is the main adsorbed Ce(Ⅳ) species. Oxidation of sorbents by adsorbed Ce ( Ⅳ ) species resulting in Ce ( Ⅲ ) release to the solution was observed. Pyridine based anion exchangers exhibited higher oxidation stability compared to the commercial strong base anion exchanger. Ce( Ⅳ ) reduction was temperature dependent and obeyed pseudo-first-order reaction kinetics. Column separation of Ce ( Ⅳ ) from La ( Ⅲ ) and Y ( Ⅲ ) was carried out from 6 mol·L^-1 nitric acid with PVP based anion exchanger. Reasonable Ce (Ⅳ) breakthrough capacity (0.7 mol·kg^-1 PVP) was achieved. No remarkable decrease of capacity was observed within 3 consequent runs. In contrast, Ce (Ⅲ) leakage due to reduction decreased and breakthrough capacity slightly increased. This effect was more pronounced with increasing temperature. Regeneration with 0.1 mol·L^- 1 nitric acid was successful (recovery 100% ± 4% ) and Ce solution of high purity ( 〉 99.97% ) with respect to La and Y content was gained.展开更多
[Objective] This study aimed to establish an efficient process for separation of phycoerythrin by using Q Sepharose Fast Flow resin and verity its feasibility for scale-up. [Method] Elution gradient, sample volume and...[Objective] This study aimed to establish an efficient process for separation of phycoerythrin by using Q Sepharose Fast Flow resin and verity its feasibility for scale-up. [Method] Elution gradient, sample volume and flow rate were optimized to determine the optimal separation condition, under which the scale-up process was verified. [Result] The optimal condition for separation of phycoerythrin by using Q Sepharose FF resin was investigated: 30 ml of laver extract was loaded to the Q Sepharose FF column with a bed volume of 8 ml; subsequently, the column was stepwise eluted with 0-0.10-0.35-1.00 mol/L NaCI solution (pH 6.0) at a constant flow rate of 1 ml/min; the elution peak under 0.35 mol/L NaCI solution was collected, and the recovery rate and purity coefficient (A565/A280) of phycoerythrin were determined as 44.3 and 1.15, respectively. Based on the established process, 75 ml of phycoerythrin extract was loaded to the Q Sepharose FF column with a bed volume of 20 ml for separation, while no significant variation was observed in the separation result. [Conclusion] Phycoerythrin can be well separated from laver extract by using Q Sepharose FF resin and the process is feasible for scale-up.展开更多
Ultra-high purity Yb_(2)O_(3) is the critical material of many high-tech materials such as laser glass and fiber,in which impurities seriously affect the laser color quality,intensity and power.In order to reduce the ...Ultra-high purity Yb_(2)O_(3) is the critical material of many high-tech materials such as laser glass and fiber,in which impurities seriously affect the laser color quality,intensity and power.In order to reduce the influence of impurities on the properties of laser materials,the purification process of Yb_(2)O_(3) was studied by comparing two kinds of resins(RT-1 and RS-1)using improved ion-exchange chromatography(IEC)method.In this study,through the synergistic improvement of resin structure and eluting system,the environmental pollution caused by ammonia water in the traditional IEC method was reduced,and the requirements of high temperature and pressure were cut.The ion exchange behavior and impurity removal mechanism in the resin column during the loading and eluting process were compared and analyzed.The experimental results show that RS-1 resin is all superior to RT-1resin in elements selectivity,ion exchange capacity and impurities removal rate.After separation and purification by IEC with RS-1 resin,the total removal rate of rare earth impurities was 77.59%and that of non-rare earth impurities was 95.86%when Yb recovery was more than 70%,both higher than that of RT-1 resin(73.26%and 83.18%).This indicates that the improved IEC method is very effective in separating and removing different metal impurities from Yb_(2)O_(3).The pilot test results of IEC method separating and purifying Yb_(2)O_(3) with RS-1 resin show that the purity of Yb_(2)O_(3) can be increased from 99.9929%to 99.9997%by IEC method.It has exhibited huge potential of preparing ultra-high purity Yb_(2)O_(3),especially the deep removal of non-rare earth impurities.展开更多
With the rapid development of the nuclear industry,more-stringent requirements are proposed for highlevel radioactive waste liquid treatment and the enrichment of isotope products.High-pressure ion exchange chromatogr...With the rapid development of the nuclear industry,more-stringent requirements are proposed for highlevel radioactive waste liquid treatment and the enrichment of isotope products.High-pressure ion exchange chromatography has been widely accepted for the fine separation of elements and nuclides due to its advantages,such as high efficiency,environmental friendliness,ease of operation,and feasibility for large-scale industrial applications.Here,we summarized the evolution of high-pressure ion exchange chromatography and the relevant research progress in ion exchange equilibrium and related separation technology.The prospects for application of high-pressure ion exchange chromatography to rare earth elements,actinide elements and isotope separation were discussed.High-pressure ion exchange chromatography represents a promising strategy for the extraction of rare earth elements and actinide elements from high-level radioactive waste liquid,as well as being an effective method for the automated production of high purity isotope products with great environmental benefits.展开更多
基金Project supported bythe Japan Societyfor the Promotion of Science (JSPS)
文摘Ce (Ⅳ) nitrato complexes were adsorbed on two anion exchangers based on polyvinyl pyridine (PVP) and quatemized PVP incorporated into porous silica matrix. The effect of nitric acid concentration (0.5~6 mol·L^-1) and temperature (278 ~318 K) on Ce( Ⅳ ) sorption efficiency was investigated. Sorption increased with increasing nitric acid concentration, indicating that [Ce(NO3)6]^2- complex is the main adsorbed Ce(Ⅳ) species. Oxidation of sorbents by adsorbed Ce ( Ⅳ ) species resulting in Ce ( Ⅲ ) release to the solution was observed. Pyridine based anion exchangers exhibited higher oxidation stability compared to the commercial strong base anion exchanger. Ce( Ⅳ ) reduction was temperature dependent and obeyed pseudo-first-order reaction kinetics. Column separation of Ce ( Ⅳ ) from La ( Ⅲ ) and Y ( Ⅲ ) was carried out from 6 mol·L^-1 nitric acid with PVP based anion exchanger. Reasonable Ce (Ⅳ) breakthrough capacity (0.7 mol·kg^-1 PVP) was achieved. No remarkable decrease of capacity was observed within 3 consequent runs. In contrast, Ce (Ⅲ) leakage due to reduction decreased and breakthrough capacity slightly increased. This effect was more pronounced with increasing temperature. Regeneration with 0.1 mol·L^- 1 nitric acid was successful (recovery 100% ± 4% ) and Ce solution of high purity ( 〉 99.97% ) with respect to La and Y content was gained.
基金Supported by National Natural Science Foundation of China(51143012)Natural Science Foundation of Shandong Province(ZR2009BM006)~~
文摘[Objective] This study aimed to establish an efficient process for separation of phycoerythrin by using Q Sepharose Fast Flow resin and verity its feasibility for scale-up. [Method] Elution gradient, sample volume and flow rate were optimized to determine the optimal separation condition, under which the scale-up process was verified. [Result] The optimal condition for separation of phycoerythrin by using Q Sepharose FF resin was investigated: 30 ml of laver extract was loaded to the Q Sepharose FF column with a bed volume of 8 ml; subsequently, the column was stepwise eluted with 0-0.10-0.35-1.00 mol/L NaCI solution (pH 6.0) at a constant flow rate of 1 ml/min; the elution peak under 0.35 mol/L NaCI solution was collected, and the recovery rate and purity coefficient (A565/A280) of phycoerythrin were determined as 44.3 and 1.15, respectively. Based on the established process, 75 ml of phycoerythrin extract was loaded to the Q Sepharose FF column with a bed volume of 20 ml for separation, while no significant variation was observed in the separation result. [Conclusion] Phycoerythrin can be well separated from laver extract by using Q Sepharose FF resin and the process is feasible for scale-up.
基金financially supported by the National Key R&D Program of China(No.2020YFC1909004)China Postdoctoral Science Foundation(Nos.2020M680615 and 2021T140581)the Youth Fund Project of GRINM。
文摘Ultra-high purity Yb_(2)O_(3) is the critical material of many high-tech materials such as laser glass and fiber,in which impurities seriously affect the laser color quality,intensity and power.In order to reduce the influence of impurities on the properties of laser materials,the purification process of Yb_(2)O_(3) was studied by comparing two kinds of resins(RT-1 and RS-1)using improved ion-exchange chromatography(IEC)method.In this study,through the synergistic improvement of resin structure and eluting system,the environmental pollution caused by ammonia water in the traditional IEC method was reduced,and the requirements of high temperature and pressure were cut.The ion exchange behavior and impurity removal mechanism in the resin column during the loading and eluting process were compared and analyzed.The experimental results show that RS-1 resin is all superior to RT-1resin in elements selectivity,ion exchange capacity and impurities removal rate.After separation and purification by IEC with RS-1 resin,the total removal rate of rare earth impurities was 77.59%and that of non-rare earth impurities was 95.86%when Yb recovery was more than 70%,both higher than that of RT-1 resin(73.26%and 83.18%).This indicates that the improved IEC method is very effective in separating and removing different metal impurities from Yb_(2)O_(3).The pilot test results of IEC method separating and purifying Yb_(2)O_(3) with RS-1 resin show that the purity of Yb_(2)O_(3) can be increased from 99.9929%to 99.9997%by IEC method.It has exhibited huge potential of preparing ultra-high purity Yb_(2)O_(3),especially the deep removal of non-rare earth impurities.
基金The financial supports from National Natural Science Foundation of China(Nos.22176077,U1730245)Natural Science Foundation of Gansu Province,China(No.20JR10RA615)the fundamental research funds for the central universities(No.lzujbky-2021-sp29)are acknowledged。
文摘With the rapid development of the nuclear industry,more-stringent requirements are proposed for highlevel radioactive waste liquid treatment and the enrichment of isotope products.High-pressure ion exchange chromatography has been widely accepted for the fine separation of elements and nuclides due to its advantages,such as high efficiency,environmental friendliness,ease of operation,and feasibility for large-scale industrial applications.Here,we summarized the evolution of high-pressure ion exchange chromatography and the relevant research progress in ion exchange equilibrium and related separation technology.The prospects for application of high-pressure ion exchange chromatography to rare earth elements,actinide elements and isotope separation were discussed.High-pressure ion exchange chromatography represents a promising strategy for the extraction of rare earth elements and actinide elements from high-level radioactive waste liquid,as well as being an effective method for the automated production of high purity isotope products with great environmental benefits.