Effective recovery of UO2+2 from wastewater is essential for nuclear fuel industry and related industries.In this study,a novel adsorbent was prepared by loading titanium(Ti4+) onto collagen fiber(TICF),and its physic...Effective recovery of UO2+2 from wastewater is essential for nuclear fuel industry and related industries.In this study,a novel adsorbent was prepared by loading titanium(Ti4+) onto collagen fiber(TICF),and its physical and chemical properties as well as adsorption to UO2+2 in nuclear fuel industrial wastewater were investigated.It is found that TICF can effectively recover UO2+2 from the wastewater with excellent adsorption capacity.The adsorption capacity is 0.62 mmol·g-1 at 303 K and pH 5.0 when the initial concentration of UO2+2 is 1.50 mmol·L-1.The adsorption isotherms can be described by the Langmuir equation and the adsorption capacity increases with temperature.The effect of co-existed F on the adsorption capacity for UO2+2 is significant,which can be eliminated by adding aluminum ions as complexing agent,while the other co-existed ions in the solutions,including HCO-3,Cl-,NO-3,Ca2+,Mg2+ and Cu2+,have little effect on the adsorption capacity for UO2+2.The saturated TICF after UO2+2 adsorption can be regenerated by using 0.2 mol·L-1 nitrate(HNO-3) as desorption agent,and the TICF can be reused at least three times.Thus the TICF is a new and effective adsorbent for the recovery of UO2+2 from the wastewater.展开更多
We report a method to produce a uniform mixture of uranium dioxide spherical particles in a tungsten matrix. This method involves mixing 0.5 weight percent of high density polyethylene binder with 60 volume percent ur...We report a method to produce a uniform mixture of uranium dioxide spherical particles in a tungsten matrix. This method involves mixing 0.5 weight percent of high density polyethylene binder with 60 volume percent uranium dioxide spheres and 40 volume percent tungsten powders. Initially, hafnium oxide spheres were used as a surrogate for uranium dioxide spheres. The HfO2/W/PE powders were thoroughly mixed in a Turbula, then mixed on a hot plate above the drop point of the binder. These powders were then densified using spark plasma sintering. Microstructure was evaluated using scanning electron microscopy, density was measured and hardness measurements were made. Initial carbon content of the powders were measured and carbon content of the sintered materials was measured. Subsequently, W/UO2/Binder powders were mixed using the same methodology to ensure the process could be used for this system. These powders were sintered using hot isostatic pressing and microstructures evaluated. The resultant microstructures contained uniform distribution of HfO2 and UO2 particles in the tungsten matrix with very low carbon content.展开更多
基金Supported by the National Natural Science Foundation of China （20976111） Sichuan Province Technologies R＆D Program（2008GZ0026）
文摘Effective recovery of UO2+2 from wastewater is essential for nuclear fuel industry and related industries.In this study,a novel adsorbent was prepared by loading titanium(Ti4+) onto collagen fiber(TICF),and its physical and chemical properties as well as adsorption to UO2+2 in nuclear fuel industrial wastewater were investigated.It is found that TICF can effectively recover UO2+2 from the wastewater with excellent adsorption capacity.The adsorption capacity is 0.62 mmol·g-1 at 303 K and pH 5.0 when the initial concentration of UO2+2 is 1.50 mmol·L-1.The adsorption isotherms can be described by the Langmuir equation and the adsorption capacity increases with temperature.The effect of co-existed F on the adsorption capacity for UO2+2 is significant,which can be eliminated by adding aluminum ions as complexing agent,while the other co-existed ions in the solutions,including HCO-3,Cl-,NO-3,Ca2+,Mg2+ and Cu2+,have little effect on the adsorption capacity for UO2+2.The saturated TICF after UO2+2 adsorption can be regenerated by using 0.2 mol·L-1 nitrate(HNO-3) as desorption agent,and the TICF can be reused at least three times.Thus the TICF is a new and effective adsorbent for the recovery of UO2+2 from the wastewater.
文摘We report a method to produce a uniform mixture of uranium dioxide spherical particles in a tungsten matrix. This method involves mixing 0.5 weight percent of high density polyethylene binder with 60 volume percent uranium dioxide spheres and 40 volume percent tungsten powders. Initially, hafnium oxide spheres were used as a surrogate for uranium dioxide spheres. The HfO2/W/PE powders were thoroughly mixed in a Turbula, then mixed on a hot plate above the drop point of the binder. These powders were then densified using spark plasma sintering. Microstructure was evaluated using scanning electron microscopy, density was measured and hardness measurements were made. Initial carbon content of the powders were measured and carbon content of the sintered materials was measured. Subsequently, W/UO2/Binder powders were mixed using the same methodology to ensure the process could be used for this system. These powders were sintered using hot isostatic pressing and microstructures evaluated. The resultant microstructures contained uniform distribution of HfO2 and UO2 particles in the tungsten matrix with very low carbon content.
