TY - JOUR
T1 - Removal of cadmium and lead from aqueous solutions by thermal activated electrolytic manganese residues
AU - Ma, Mengyu
AU - Du, Yaguang
AU - Bao, Shenxu
AU - Li, Jia
AU - Wei, Hua
AU - Lv, Ying
AU - Song, Xiaolong
AU - Zhang, Tiancheng
AU - Du, Dongyun
N1 - Funding Information:
The project is financially sustained by the National Natural Science Foundation of China ( 51804354 ), and the Scientific Special of Central Higher Education Institutions (No. CZZ20003 ).
Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2020/12/15
Y1 - 2020/12/15
N2 - Electrolytic manganese residues (EMR) is produced from the electrolysis manganese industry. In this study, the thermal activated EMRs (T-EMR) were used to adsorb cadmium and lead from aqueous solution. X-ray diffractometer (XRD), scanning electron microscope-Energy Dispersive Spectrometer (SEM-EDS), X-ray photoelectron spectroscopy (XPS) were adopted to characterize EMR before and after the modification, and the performance and adsorption mechanisms of T-EMR for cadmium and lead were determined. Results show that the pH has a strong influence on the adsorption of cadmium and lead and the maximum adsorption capacity can be achieved at pH 6. The adsorption of Cd(II) can be better fitted by the Lagergren pseudo-first-order dynamic model, while that of Pb(II) fits the pseudo-second-order kinetic model better. The Freundlich isotherm model fits the adsorption of two metals better than Langmuir model. The thermodynamic results demonstrate that the adsorption of Cd(II) or Pb(II) on T-EMR is endothermic and spontaneous. As the nitric acid with pH 0.5 was used, nearly all of the adsorbed Cd(II) and 75% Pb(II) can be desorbed from the loaded T-EMR. It is concluded that the adsorption of Cd(II) and Pb(II) on T-EMR is in virtue of electrostatic attraction, ion-exchange and surface precipitation. The heavy metals are mainly adsorbed on ferric and manganese oxides and silicate minerals in T-EMR by electrostatic attraction. In addition, cadmium and lead also can be adsorbed via the ion exchange reaction. Moreover, some Pb(II) are adsorbed by forming lead sulfate. Thus, T-EMR may be an environmentally-friendly, effective adsorbent for the removal of heavy metals from aqueous solution.
AB - Electrolytic manganese residues (EMR) is produced from the electrolysis manganese industry. In this study, the thermal activated EMRs (T-EMR) were used to adsorb cadmium and lead from aqueous solution. X-ray diffractometer (XRD), scanning electron microscope-Energy Dispersive Spectrometer (SEM-EDS), X-ray photoelectron spectroscopy (XPS) were adopted to characterize EMR before and after the modification, and the performance and adsorption mechanisms of T-EMR for cadmium and lead were determined. Results show that the pH has a strong influence on the adsorption of cadmium and lead and the maximum adsorption capacity can be achieved at pH 6. The adsorption of Cd(II) can be better fitted by the Lagergren pseudo-first-order dynamic model, while that of Pb(II) fits the pseudo-second-order kinetic model better. The Freundlich isotherm model fits the adsorption of two metals better than Langmuir model. The thermodynamic results demonstrate that the adsorption of Cd(II) or Pb(II) on T-EMR is endothermic and spontaneous. As the nitric acid with pH 0.5 was used, nearly all of the adsorbed Cd(II) and 75% Pb(II) can be desorbed from the loaded T-EMR. It is concluded that the adsorption of Cd(II) and Pb(II) on T-EMR is in virtue of electrostatic attraction, ion-exchange and surface precipitation. The heavy metals are mainly adsorbed on ferric and manganese oxides and silicate minerals in T-EMR by electrostatic attraction. In addition, cadmium and lead also can be adsorbed via the ion exchange reaction. Moreover, some Pb(II) are adsorbed by forming lead sulfate. Thus, T-EMR may be an environmentally-friendly, effective adsorbent for the removal of heavy metals from aqueous solution.
KW - Adsorption
KW - Cadmium
KW - Electrolytic manganese residue
KW - Lead
KW - Thermal activation
UR - http://www.scopus.com/inward/record.url?scp=85089375972&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85089375972&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2020.141490
DO - 10.1016/j.scitotenv.2020.141490
M3 - Article
C2 - 32810808
AN - SCOPUS:85089375972
VL - 748
JO - Science of the Total Environment
JF - Science of the Total Environment
SN - 0048-9697
M1 - 141490
ER -