In order to realize resource utilization of industrial tungsten residue and treatment of heavy metal wastewater in mining and metallurgical area of south China,a novel ceramsite was prepared with the main raw material...In order to realize resource utilization of industrial tungsten residue and treatment of heavy metal wastewater in mining and metallurgical area of south China,a novel ceramsite was prepared with the main raw materials of diatomite and tungsten residue.The adsorption behavior of copper ions in solution on the ceramsite was investigated.Results indicated that the surface of the newly-developed ceramsite was rough and porous.There were lots of pores across the ceramsite from inner to outside.MnFe2O4 was one of the main components of the ceramsite.The Cu^2+adsorption capacity by the ceramsite reached 9.421 mg/g with copper removal efficiency of 94.21%at 303 K,initial Cu^2+concentration of 100 mg/L and dosage of 0.5 g after 300 min adsorption.With increase of ceramsite dosage,the total adsorption amount of Cu^2+increased,but the adsorption capacity decreased.The adsorption capacity increased with the increase of solution p H.The isothermal adsorption of Cu^2+by the ceramsite fitted the Freundlich model better.The adsorption mainly occurred on a heterogeneous surface,and was a favorable process.The adsorption process closely followed the pseudo-second kinetic equation.In initial stage of wastewater treatment,the adsorption process should be controlled mainly by diffusion,and the removal of Cu^2+can be improved by enhancing agitation.展开更多
Ammonium pollution becomes severe during mining of ionic rare earth-ores in southern China.As one of the main clayminerals in soils of ionic rare earth mines,halloysite plays an important role in ammonium adsorption.I...Ammonium pollution becomes severe during mining of ionic rare earth-ores in southern China.As one of the main clayminerals in soils of ionic rare earth mines,halloysite plays an important role in ammonium adsorption.In this study,the saturatedadsorption capacity,factors affecting adsorption and adsorption kinetics of halloysite for ammonium were investigated.The resultsindicated that the ammonium adsorption of halloysite was saturated with1.66mg/g at303K,pH of5.6and initial ammoniumconcentration of600mg/L(about half of the actual initial in-situ leaching concentration).When the initial concentration of NH4?-N,pH values and temperatures(288K to313K)increased,the ammonium adsorption capacity of halloysite increased.The ammoniumisothermal adsorption of halloysite matched the Langmuir and Freundlich isotherms.The adsorption process of ionic rare earthmining soils for ammonium was favorable.And the adsorption process followed closely the pseudo-second kinetic equation.展开更多
基金Project(51674305)supported by the National Natural Science Foundation of ChinaKey Project(1602FKDC007)supported by Science and Technology Program of Gansu Province,China+1 种基金Projects(2016YT03N101,2017A090905024)supported by Science and Technology Program of Guangdong Province,ChinaProject(NSFJ2015-K06)supported by Jiangxi University of Science and Technology,China
文摘In order to realize resource utilization of industrial tungsten residue and treatment of heavy metal wastewater in mining and metallurgical area of south China,a novel ceramsite was prepared with the main raw materials of diatomite and tungsten residue.The adsorption behavior of copper ions in solution on the ceramsite was investigated.Results indicated that the surface of the newly-developed ceramsite was rough and porous.There were lots of pores across the ceramsite from inner to outside.MnFe2O4 was one of the main components of the ceramsite.The Cu^2+adsorption capacity by the ceramsite reached 9.421 mg/g with copper removal efficiency of 94.21%at 303 K,initial Cu^2+concentration of 100 mg/L and dosage of 0.5 g after 300 min adsorption.With increase of ceramsite dosage,the total adsorption amount of Cu^2+increased,but the adsorption capacity decreased.The adsorption capacity increased with the increase of solution p H.The isothermal adsorption of Cu^2+by the ceramsite fitted the Freundlich model better.The adsorption mainly occurred on a heterogeneous surface,and was a favorable process.The adsorption process closely followed the pseudo-second kinetic equation.In initial stage of wastewater treatment,the adsorption process should be controlled mainly by diffusion,and the removal of Cu^2+can be improved by enhancing agitation.
基金Project(51674305)supported by the National Natural Science Foundation of ChinaProject(1602FKDC007)supported by Science and Technology Program of Gansu Province,ChinaProject(NSFJ2015-K06)supported by the Jiangxi University of Science and Technology,China
文摘Ammonium pollution becomes severe during mining of ionic rare earth-ores in southern China.As one of the main clayminerals in soils of ionic rare earth mines,halloysite plays an important role in ammonium adsorption.In this study,the saturatedadsorption capacity,factors affecting adsorption and adsorption kinetics of halloysite for ammonium were investigated.The resultsindicated that the ammonium adsorption of halloysite was saturated with1.66mg/g at303K,pH of5.6and initial ammoniumconcentration of600mg/L(about half of the actual initial in-situ leaching concentration).When the initial concentration of NH4?-N,pH values and temperatures(288K to313K)increased,the ammonium adsorption capacity of halloysite increased.The ammoniumisothermal adsorption of halloysite matched the Langmuir and Freundlich isotherms.The adsorption process of ionic rare earthmining soils for ammonium was favorable.And the adsorption process followed closely the pseudo-second kinetic equation.