A novel membrane distillation concentration method was used m prepare high concentration polyaluminum chloride (PAC1) with high content of AID or Ale. 2.52 mol/L PACl1 with 88% Alb and 2.38 mol/L PACl2 with 61% Ale ...A novel membrane distillation concentration method was used m prepare high concentration polyaluminum chloride (PAC1) with high content of AID or Ale. 2.52 mol/L PACl1 with 88% Alb and 2.38 mol/L PACl2 with 61% Ale were successfully prepared. Three coagulants, AlCl3, PACl1 and PACl2 were investigated on their hydrolysis behavior and speciation under different conditions. The effects of pH and dilution ratio on Al species distribution were investigated by ferron assay. Experimental result showed that pH had a significant effect on Al species distribution for the three coagulants. Dilution ratio had little effects on Alb and Alc distribution in whole dilution process except the beginning for PACl1 and PACl2. The results indicated that transformation of Al depends largely on their original composition. AlCl3 was the most unstable coagulant among these three coagulants during hydrolysis process. PACl1 and PACl2 with significant amounts of highly charged and stable polynuclear aluminum hydrolysis products were less affected by the hydrolysis conditions and could maintain high speciation stability under various conditions.展开更多
In this paper, the partitioning of copper between surfacial sediments and overlaying water in Dawu-Le An River, which was contaminated by acid mine drainage resulted from mining activities,was studied by field investi...In this paper, the partitioning of copper between surfacial sediments and overlaying water in Dawu-Le An River, which was contaminated by acid mine drainage resulted from mining activities,was studied by field investigation and acid dissolution experiment.Simulated adsorption experiments were carried out to study the adsorption of copper on amorphous iron oxyhydroxide and ore tailing particles.The results showed that it was the binding of copper onto the surface of amorphous Fe/Al oxyhydroxides and ore tailing particles that regulated the concentrations of dissolved Cu at downstream of Dawu River and its inlet into Le An River.A significant part of adsorbed copper was likely to be associated with amorphous Fe/Al oxyhydroxides coated on the surface of ore tailing particles. A simplified surface complexation model can be used to describe the adsorption behavior in the river.展开更多
A novel material, alumina supported on carbon nanotubes (Al2O3/CNT), was prepared from carbon nano-tubes and A1(NO3)3. X-ray diffraction (XRD) spectra demonstrate that alumina is amorphous, and scanning electron micro...A novel material, alumina supported on carbon nanotubes (Al2O3/CNT), was prepared from carbon nano-tubes and A1(NO3)3. X-ray diffraction (XRD) spectra demonstrate that alumina is amorphous, and scanning electron microscope (SEM) images show that CNT and alumina are homogeneously mixed. Furthermore, the fluoride adsorption behavior on the surface of Al2O3/CNT has been investigated and compared with other adsorbents. The results indicate that Al2O3/CNT has a high adsorption capacity, with a saturation adsorption capacity of 39.4 mg/g. It is also found that the adsorption capacity of Al2O3/CNT is 3.0-4.5 times that of γ-Al2O3 while almost equal to that of IRA-410 polymeric resin at 25°C . The adsorption isotherms of fluoride on Al2O3/CNT fit the Freundlich equation well, and optimal pH ranging from 5.0 to 9.0.展开更多
基金supported by the National Natural Science Foundation of China (No 50708109, 20577061,40673003)the National Hi-Tech Research and Develop-ment Key Program (863) of China (No 2007AA06Z339)the Special Fund from the State Key Laboratory of Environmental Aquatic Chemistry (No 09Y02ESPCR,09Z01ESPCR)
文摘A novel membrane distillation concentration method was used m prepare high concentration polyaluminum chloride (PAC1) with high content of AID or Ale. 2.52 mol/L PACl1 with 88% Alb and 2.38 mol/L PACl2 with 61% Ale were successfully prepared. Three coagulants, AlCl3, PACl1 and PACl2 were investigated on their hydrolysis behavior and speciation under different conditions. The effects of pH and dilution ratio on Al species distribution were investigated by ferron assay. Experimental result showed that pH had a significant effect on Al species distribution for the three coagulants. Dilution ratio had little effects on Alb and Alc distribution in whole dilution process except the beginning for PACl1 and PACl2. The results indicated that transformation of Al depends largely on their original composition. AlCl3 was the most unstable coagulant among these three coagulants during hydrolysis process. PACl1 and PACl2 with significant amounts of highly charged and stable polynuclear aluminum hydrolysis products were less affected by the hydrolysis conditions and could maintain high speciation stability under various conditions.
文摘In this paper, the partitioning of copper between surfacial sediments and overlaying water in Dawu-Le An River, which was contaminated by acid mine drainage resulted from mining activities,was studied by field investigation and acid dissolution experiment.Simulated adsorption experiments were carried out to study the adsorption of copper on amorphous iron oxyhydroxide and ore tailing particles.The results showed that it was the binding of copper onto the surface of amorphous Fe/Al oxyhydroxides and ore tailing particles that regulated the concentrations of dissolved Cu at downstream of Dawu River and its inlet into Le An River.A significant part of adsorbed copper was likely to be associated with amorphous Fe/Al oxyhydroxides coated on the surface of ore tailing particles. A simplified surface complexation model can be used to describe the adsorption behavior in the river.
基金This work was supported by the National Natural Science Foundation of China (Grant No. 50178067).
文摘A novel material, alumina supported on carbon nanotubes (Al2O3/CNT), was prepared from carbon nano-tubes and A1(NO3)3. X-ray diffraction (XRD) spectra demonstrate that alumina is amorphous, and scanning electron microscope (SEM) images show that CNT and alumina are homogeneously mixed. Furthermore, the fluoride adsorption behavior on the surface of Al2O3/CNT has been investigated and compared with other adsorbents. The results indicate that Al2O3/CNT has a high adsorption capacity, with a saturation adsorption capacity of 39.4 mg/g. It is also found that the adsorption capacity of Al2O3/CNT is 3.0-4.5 times that of γ-Al2O3 while almost equal to that of IRA-410 polymeric resin at 25°C . The adsorption isotherms of fluoride on Al2O3/CNT fit the Freundlich equation well, and optimal pH ranging from 5.0 to 9.0.