title: Adsorption of copper ions onto microwave stabilized heavy metal sludge.
abstract: Microwave stabilized heavy metal sludge was used as an adsorbent to remove the copper ions from aqueous solution. The adsorption characteristics of copper on the stabilized-sludge were studied by various models, such as Freundlich and Langmuir isotherm equation. Results show that the pH(zpc) of stabilized-sludge was at 9.2-9.5. Moreover, the adsorption of copper ions onto the stabilized-sludge surface was mainly on account of the heterogeneous surface of the stabilized-sludge. In the dynamic study, the experimental data was fitted to the intraparticle diffusion model, pseudo-first order model and pseudo-second order model. However, the experimental data was only well correlated with pseudo-second order model with the correlation coefficient>0.995. Furthermore, both Freundlich and Langmuir isotherm equations were found to represent the measured adsorption data well. From the Langmuir equation, the adsorption capacity increased from 18 to 28 mg/g as the temperature rose from 15 to 55 degrees C, since this adsorption process was an endothermic reaction. After this adsorption process, copper ions can be concentrated on and in a small bead and recovery efficiently.
authors.affiliation: Research Center for Environmental Pollution Prevention and Control Technology, Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Road, Taipei 106, Taiwan, ROC.
authors.forename: Ching-Hong
authors.initials: CH
authors.lastname: Hsieh
authors.forename: Shang-Lien
authors.initials: SL
authors.lastname: Lo
authors.forename: Wen-Hui
authors.initials: WH
authors.lastname: Kuan
authors.forename: Ching-Lung
authors.initials: CL
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D003300:Copper / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D019216:Metals, Heavy / Q000737:chemistry*; D008872:Microwaves; D012722:Sewage
chemical_list: D019216:Metals, Heavy; D012722:Sewage; D003300:Copper