adsorption of copper(ii) from an wastewater effluent of electroplating industry by poly(ethyleneimine)-functionalized silica

the poly(ethyleneimine)-functionalized silica has been developed successfully as an effective adsorbent for the adsorption removal of cu(ii) ions from electroplating wastewater. the influences of ph, contact time and initial concentration of cu(ii) ions on the adsorption capacity and the effect of adsorbent dosage on the removal efficiency of cu(ii) ions from electroplating wastewater were investigated. the adsorption behaviors and mechanisms of cu(ii) ions onto poly(ethyleneimine)-functionalized silica were also studied in details. the uptake of cu(ii) ions on poly(ethyleneimine)-functionalized silica was constant in the range of ph 4-8. the poly(ethyleneimine)-functionalized silica offered a fast rate for the adsorption of cu(ii) ions and reached an equilibrium state within 30 min. the results of static batch experiment indicated that the maximum static adsorption capacity of cu(ii) ions on pei-functionalized silica was 31.8 mg/g. the adsorption process was found to follow a pseudo-second-order rate mechanism. langmuir adsorption isotherms fitted well in the experimental data. the optimum dosage of poly(ethyleneimine)-functionalized silica for the removal cu(ii) ions from electroplating wastewater was 10 g/l. the removal efficiency of cu(ii) ions from electroplating wastewater was 92.6%.some scale-up experiments were also investigated to offer the reference for water treatment. the results showed that poly(ethyleneimine)-functionalized silica could be employed as an effective adsorbent for the removal of cu(ii) ions from electroplating wastewater.