In this study, a three-dimensional ordered macroporous hematite was prepared using the polystyrene colloid crystal templates and characterized by X-ray diffraction, scanning electron microscope, transmission electron ...In this study, a three-dimensional ordered macroporous hematite was prepared using the polystyrene colloid crystal templates and characterized by X-ray diffraction, scanning electron microscope, transmission electron microscope, and nitrogen adsorption isotherm. The as-prepared hematite shows a porous structure consisting of the macropores about 200 nm in diameter and the walls about 20 nm in thickness. The adsorption of Pb2+ and Cd2+ ions in aqueous solution by this hematite was also evaluated. At room temperature, each gram hematite adsorbs 12.5 mg of Pb2+ ions and 7.0 mg of Cd2+ ions. The results suggest that the obtained hematite should be a promising adsorbent to remove Pb2+ and Cd2+ ions, and other heavy metal ions from aqueous solution.展开更多
In this study, the effects of experimental conditions including the MBR equipped novel device and different operating modes on permeate flux were studied. The results show that the MBR equipped novel device can reduce...In this study, the effects of experimental conditions including the MBR equipped novel device and different operating modes on permeate flux were studied. The results show that the MBR equipped novel device can reduce the resistance and enhance the flux, decreasing the total resistance ( Rt = 9.649) to 5.962 and increasing the permeate flux to 15 - 20 L/m2hr. The permeate flux of intermittent operating mode is more than that of continuous operation and the value of the permeate flux is between 15 l/m2hr and 20 l/m2hr. The MBR equipped novel device which adopting intermittent operating mode is most effective in this study and the value of permeate flux is between 20 l/m2hr and 25 l/m2hr.展开更多
Selective recovery of scandium and titanium from red mud leaching solution was achieved through neutralization precipitation followed by acid leaching approach.In the neutralization precipitation section,the effects o...Selective recovery of scandium and titanium from red mud leaching solution was achieved through neutralization precipitation followed by acid leaching approach.In the neutralization precipitation section,the effects of pH,temperature and reaction time on metal precipitation efficiency were investigated.Under the optimal co ndition,the precipitation efficiencies of scandium and titanium were 93.74%and 99.47%,respectively.In the acid leaching section,the effects of acidity,temperature,reaction time,and raffinate to acid solution ratio on leaching efficiency were investigated.Under the optimal condition,the leaching efficiencies of scandium and titanium were 99.97%and 5.44%,respectively.The loss of scandium and titanium were 6.3%and 5.9%,respectively.Compared with the traditional extraction procedure of scandium in red mud,this method could separate titanium from scandium effectively,which is beneficial for the purification of the products and improvement of value of the metal.展开更多
文摘In this study, a three-dimensional ordered macroporous hematite was prepared using the polystyrene colloid crystal templates and characterized by X-ray diffraction, scanning electron microscope, transmission electron microscope, and nitrogen adsorption isotherm. The as-prepared hematite shows a porous structure consisting of the macropores about 200 nm in diameter and the walls about 20 nm in thickness. The adsorption of Pb2+ and Cd2+ ions in aqueous solution by this hematite was also evaluated. At room temperature, each gram hematite adsorbs 12.5 mg of Pb2+ ions and 7.0 mg of Cd2+ ions. The results suggest that the obtained hematite should be a promising adsorbent to remove Pb2+ and Cd2+ ions, and other heavy metal ions from aqueous solution.
文摘In this study, the effects of experimental conditions including the MBR equipped novel device and different operating modes on permeate flux were studied. The results show that the MBR equipped novel device can reduce the resistance and enhance the flux, decreasing the total resistance ( Rt = 9.649) to 5.962 and increasing the permeate flux to 15 - 20 L/m2hr. The permeate flux of intermittent operating mode is more than that of continuous operation and the value of the permeate flux is between 15 l/m2hr and 20 l/m2hr. The MBR equipped novel device which adopting intermittent operating mode is most effective in this study and the value of permeate flux is between 20 l/m2hr and 25 l/m2hr.
基金Project supported by the National Natural Science Foundation of China(21707167)。
文摘Selective recovery of scandium and titanium from red mud leaching solution was achieved through neutralization precipitation followed by acid leaching approach.In the neutralization precipitation section,the effects of pH,temperature and reaction time on metal precipitation efficiency were investigated.Under the optimal co ndition,the precipitation efficiencies of scandium and titanium were 93.74%and 99.47%,respectively.In the acid leaching section,the effects of acidity,temperature,reaction time,and raffinate to acid solution ratio on leaching efficiency were investigated.Under the optimal condition,the leaching efficiencies of scandium and titanium were 99.97%and 5.44%,respectively.The loss of scandium and titanium were 6.3%and 5.9%,respectively.Compared with the traditional extraction procedure of scandium in red mud,this method could separate titanium from scandium effectively,which is beneficial for the purification of the products and improvement of value of the metal.
