Based on the inhibitory effect of metal ions on the decolourization reaction of a dye taking place in a mixed micellar medium, a differential rate method was developed for the detection of metal ions. The present kine...Based on the inhibitory effect of metal ions on the decolourization reaction of a dye taking place in a mixed micellar medium, a differential rate method was developed for the detection of metal ions. The present kinetic spectrophotometric system has several advantages due to introduction of the mixed micelles.展开更多
Rectifier diode production wastewater that contains acid,alkali and heavy metal ions in a company was treated by using neutralization/coagulation sedimentation method.Firstly,pH of wastewater was adjusted via neutrali...Rectifier diode production wastewater that contains acid,alkali and heavy metal ions in a company was treated by using neutralization/coagulation sedimentation method.Firstly,pH of wastewater was adjusted via neutralization reaction,and then heavy metal ions(Cu^(2+),Cr^(2+)and Pb^(2+))were removed by adding coagulant PAC and flocculant PAM.Different acid-alkali neutralization reactions were conducted under the process condition to analyze and compare their neutralization effects.The results showed that removal rates of heavy metal ions were high after coagulation test:Cu^(2+),Pb^(2+)and Cr^(2+)contents dropped from 13.230,0.032,and 1.720mg/L to 0.3,0.001,and 0.24mg/L;besides,total iron,total manganese and turbidity all had very good removal effects.展开更多
The effects of Na＋, concentrations on the crystal Mg2＋, A13＋ and Fe3＋ ion morphology of calcium sulfate hemihydrate whiskers formed via a hydrothermal method have been studied. In the presence of A13＋ concentrati...The effects of Na＋, concentrations on the crystal Mg2＋, A13＋ and Fe3＋ ion morphology of calcium sulfate hemihydrate whiskers formed via a hydrothermal method have been studied. In the presence of A13＋ concentrations higher than 1x10-3 mol/L the whiskers were significantly shorter and thicker and the presence of Mg2＋ and Fe3＋ resulted in shorter whiskers. The presence of Nan did not affect the morphology of the whiskers. Through elemental analysis, it was determined that Mg2＋ and A13＋ were selectively adsorbed on the surfaces of the crystals, whereas Fe3＋ underwent a hydrolysis reaction to form a brown precipitate which decreased the ion concentration in the solution. These results indicate that in raw materials used for the industrial preparation of calcium sulfate whiskers, AI3＋ and Fe3＋ should be removed and the Mg2＋ concentration should be less than 8 x 10-3 mol/L in order to obtain pure whiskers with high aspect ratios.展开更多
文摘Based on the inhibitory effect of metal ions on the decolourization reaction of a dye taking place in a mixed micellar medium, a differential rate method was developed for the detection of metal ions. The present kinetic spectrophotometric system has several advantages due to introduction of the mixed micelles.
文摘Rectifier diode production wastewater that contains acid,alkali and heavy metal ions in a company was treated by using neutralization/coagulation sedimentation method.Firstly,pH of wastewater was adjusted via neutralization reaction,and then heavy metal ions(Cu^(2+),Cr^(2+)and Pb^(2+))were removed by adding coagulant PAC and flocculant PAM.Different acid-alkali neutralization reactions were conducted under the process condition to analyze and compare their neutralization effects.The results showed that removal rates of heavy metal ions were high after coagulation test:Cu^(2+),Pb^(2+)and Cr^(2+)contents dropped from 13.230,0.032,and 1.720mg/L to 0.3,0.001,and 0.24mg/L;besides,total iron,total manganese and turbidity all had very good removal effects.
文摘The effects of Na＋, concentrations on the crystal Mg2＋, A13＋ and Fe3＋ ion morphology of calcium sulfate hemihydrate whiskers formed via a hydrothermal method have been studied. In the presence of A13＋ concentrations higher than 1x10-3 mol/L the whiskers were significantly shorter and thicker and the presence of Mg2＋ and Fe3＋ resulted in shorter whiskers. The presence of Nan did not affect the morphology of the whiskers. Through elemental analysis, it was determined that Mg2＋ and A13＋ were selectively adsorbed on the surfaces of the crystals, whereas Fe3＋ underwent a hydrolysis reaction to form a brown precipitate which decreased the ion concentration in the solution. These results indicate that in raw materials used for the industrial preparation of calcium sulfate whiskers, AI3＋ and Fe3＋ should be removed and the Mg2＋ concentration should be less than 8 x 10-3 mol/L in order to obtain pure whiskers with high aspect ratios.
