Study on the Adsorption Characteristics of Calcareous Sand for Pb(II), Cu(II) and Cd(II) in Aqueous Solution

The adsorption characteristics of calcareous sand for heavy metals Pb(II), Cu(II) and Cd(II) have been studied by batch testing in this study. influence the solid–liquid ratio, initial pH0 value, ionic strength, reaction time, temperature concentration on has investigated. Test results indicate that pH ratio a significant removal efficiency. At T = 30 °C, r 1.0 g/L, C0 1000 mg/L 12 h reaction, efficiencies are 97.6%, 88.15% 65.72%, respectively. quantity is more than 80% maximum within 60 min, equilibrium can be reached 120 min. pseudo-second-order kinetic model suitable to simulate dynamic process sand, isothermal found obey Langmuir model. Calcareous very high capacity Cd(II), with Qm 1052.95 mg/g, 1329.84 mg/g 1050.56 Thermodynamic test spontaneously exothermic low favorable reaction.