The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid(D2EHPA) as extracting agent.The extracting agents were supported on a macro porous polymeric resi...The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid(D2EHPA) as extracting agent.The extracting agents were supported on a macro porous polymeric resin XAD-7(solid phase).Yttrium ions extraction and discharge tests were performed,firstly from a synthetic aqueous solution of 100 mg/L Y(liquid phase) at 25℃ with stirring.The effects of pH of aqueous solutions bearing yttrium,volume fraction of extracting agents and the solid/liquid(S/L)ratio on the yttrium recovery were studied.The most favorable conditions for yttrium ions extraction are;20 vol% D_(2)EHPA functionalized resin,pH=1.5 and an S/L ratio of 10 mg/mL The discharge of yttrium ions was done under the same conditions of extraction stage,using a 2 mol/L [H_(2)SO_(4)] as stripping solution.Up to 80% yttrium is extracted,while 75% yttrium is recovered in the striping solution.In all experiments,the reaction equilibrium is reached after 20 min,and the kinetics for the extraction stage was determined as a second-order model.Also,experiments were carried out to discharge the yttriumloaded resins,and it has been determined that the best pH value to strip the Y ions is 1.5.Cyclic tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its efficiency.Finally,the proposed process was tested in a real solution with Y ions fro m a waste fluorescent la mp powder leached in H_(2)SO_(4),demonstrating the ability to effectively recover yttrium,separating it from various metals from the studied residue.展开更多
Tannic acid and its related compounds are known as refractory organic pollutants, and it can create serious problems for the environment. The adsorption and desorption studies of tannic acid on commercial resins XAD-7...Tannic acid and its related compounds are known as refractory organic pollutants, and it can create serious problems for the environment. The adsorption and desorption studies of tannic acid on commercial resins XAD-7 and D-201 are performed, and all data indicates resin XAD-7 can be used as an effective adsorbent for removing tannic acid during water/wastewater treatment. Furthermore, adsorption thermodynamics studies indicate different adsorption mechanisms for TA on XAD-7 and D-201. FT-IR and solid state 13C-NMR spectroscopy are used to explain the adsorption force between XAD-7 and TA. It suggests that hydrogen bonding is the main adsorption force for TA. Finally, XAD-7＇s adsorption capacity in the presence of different metal ions is investigated, which indicates that heavy metal ions in solutions can decrease the adsorption capacity for TA on ester resin XAD-7.展开更多
Objective: To compare the protective effects of removingcirculatory TNF by specific immunoadsorption and by nonspeciflc Amberlite XAD-7 adsorption on experimental endotoxin shock. Methods: New Zealand white rabbits re...Objective: To compare the protective effects of removingcirculatory TNF by specific immunoadsorption and by nonspeciflc Amberlite XAD-7 adsorption on experimental endotoxin shock. Methods: New Zealand white rabbits receiving a lethal dose of endotoxin underwent hemoperfusion through immunoadsorbent or Amberlite BAD-7. Plasma TNF levels. efficiency of the adsorbents and the survival rate were observed. Results: After 2 h of hemopcrfusion through immunoadsorhent or Amberlite XAD-7. plasma TNF levels were significantly lower than those in the control group(P<0.01). and the best result was shown by immunoadsorption (P<0. 01). The 12 h and 18 h survival rates were 70% and 30% in the immunoadsorption group, and 30% and 5% in the Amberlite XAD-7 group respectively (P<0. 05). Conclusion: Compared with the nonspecific Amberlite XAD-7 adsorption,the specific imrnunoadsorption might be a more effective method of removing circulatory TNF and improve the survival rate in endotoxin shock.展开更多
基金Project supported by Secretariat of Research and Postgraduate Studies National Polytechnic Institute (20221369 and 20231939)Consejo Nacional de Ciencia y Tecnologia CONACyT。
文摘The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid(D2EHPA) as extracting agent.The extracting agents were supported on a macro porous polymeric resin XAD-7(solid phase).Yttrium ions extraction and discharge tests were performed,firstly from a synthetic aqueous solution of 100 mg/L Y(liquid phase) at 25℃ with stirring.The effects of pH of aqueous solutions bearing yttrium,volume fraction of extracting agents and the solid/liquid(S/L)ratio on the yttrium recovery were studied.The most favorable conditions for yttrium ions extraction are;20 vol% D_(2)EHPA functionalized resin,pH=1.5 and an S/L ratio of 10 mg/mL The discharge of yttrium ions was done under the same conditions of extraction stage,using a 2 mol/L [H_(2)SO_(4)] as stripping solution.Up to 80% yttrium is extracted,while 75% yttrium is recovered in the striping solution.In all experiments,the reaction equilibrium is reached after 20 min,and the kinetics for the extraction stage was determined as a second-order model.Also,experiments were carried out to discharge the yttriumloaded resins,and it has been determined that the best pH value to strip the Y ions is 1.5.Cyclic tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its efficiency.Finally,the proposed process was tested in a real solution with Y ions fro m a waste fluorescent la mp powder leached in H_(2)SO_(4),demonstrating the ability to effectively recover yttrium,separating it from various metals from the studied residue.
基金supported by the National Natural Science Fundation of China(No.50778088)China National Funds for Distinguished Young Scientists(No.50825802)
文摘Tannic acid and its related compounds are known as refractory organic pollutants, and it can create serious problems for the environment. The adsorption and desorption studies of tannic acid on commercial resins XAD-7 and D-201 are performed, and all data indicates resin XAD-7 can be used as an effective adsorbent for removing tannic acid during water/wastewater treatment. Furthermore, adsorption thermodynamics studies indicate different adsorption mechanisms for TA on XAD-7 and D-201. FT-IR and solid state 13C-NMR spectroscopy are used to explain the adsorption force between XAD-7 and TA. It suggests that hydrogen bonding is the main adsorption force for TA. Finally, XAD-7＇s adsorption capacity in the presence of different metal ions is investigated, which indicates that heavy metal ions in solutions can decrease the adsorption capacity for TA on ester resin XAD-7.
文摘Objective: To compare the protective effects of removingcirculatory TNF by specific immunoadsorption and by nonspeciflc Amberlite XAD-7 adsorption on experimental endotoxin shock. Methods: New Zealand white rabbits receiving a lethal dose of endotoxin underwent hemoperfusion through immunoadsorbent or Amberlite BAD-7. Plasma TNF levels. efficiency of the adsorbents and the survival rate were observed. Results: After 2 h of hemopcrfusion through immunoadsorhent or Amberlite XAD-7. plasma TNF levels were significantly lower than those in the control group(P<0.01). and the best result was shown by immunoadsorption (P<0. 01). The 12 h and 18 h survival rates were 70% and 30% in the immunoadsorption group, and 30% and 5% in the Amberlite XAD-7 group respectively (P<0. 05). Conclusion: Compared with the nonspecific Amberlite XAD-7 adsorption,the specific imrnunoadsorption might be a more effective method of removing circulatory TNF and improve the survival rate in endotoxin shock.
