Enhanced Pb(II) adsorption onto functionalized ordered mesoporous carbon (OMC) from aqueous solutions: the important role of surface property and adsorption mechanism

Qiyu Lian; Lunguang Yao; Zaki Uddin Ahmad; Daniel Dianchen Gang; Mas Iwan Konggidinata; August A Gallo; Mark E Zappi

doi:10.1007/s11356-020-08487-9

Enhanced Pb(II) adsorption onto functionalized ordered mesoporous carbon (OMC) from aqueous solutions: the important role of surface property and adsorption mechanism

Environ Sci Pollut Res Int. 2020 Jul;27(19):23616-23630. doi: 10.1007/s11356-020-08487-9. Epub 2020 Apr 15.

Authors

Qiyu Lian^{1

2}, Lunguang Yao³, Zaki Uddin Ahmad^{1

4}, Daniel Dianchen Gang^{5

6}, Mas Iwan Konggidinata^{2

7}, August A Gallo⁸, Mark E Zappi^{2

7}

Affiliations

¹ Department of Civil Engineering, University of Louisiana at Lafayette, P. O. Box 43598, Lafayette, LA, 70504, USA.
² Center for Environmental Technology, The Energy Institute of Louisiana, P. O. Box 43597, Lafayette, LA, 70504, USA.
³ Henan Key Laboratory of Ecological Security, Collaborative Innovation Center of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project of Henan Province, Nanyang Normal University, 1638 Wolong Rd, Nanyang, Henan, People's Republic of China.
⁴ Wastewater Infrastructure Planning, Houston Water, Houston Public Works, 611 Walker Street (18th Floor), Houston, TX, 77002, USA.
⁵ Department of Civil Engineering, University of Louisiana at Lafayette, P. O. Box 43598, Lafayette, LA, 70504, USA. Gang@louisiana.edu.
⁶ Center for Environmental Technology, The Energy Institute of Louisiana, P. O. Box 43597, Lafayette, LA, 70504, USA. Gang@louisiana.edu.
⁷ Department of Chemical Engineering, University of Louisiana at Lafayette, P. O. Box 43675, Lafayette, LA, 70504, USA.
⁸ Department of Chemistry, University of Louisiana at Lafayette, P. O. Box 43700, Lafayette, LA, 70504, USA.

PMID: 32291646
DOI: 10.1007/s11356-020-08487-9

Abstract

Functionalized ordered mesoporous carbon (MOMC-NP) was synthesized by chemical modification using HNO₃ and H₃PO₄ to enhance Pb(II) adsorption. The phosphate functional group represented by P-O-C bonding onto the surface of OMC was verified by FT-IR and XPS. Batch adsorption experiments revealed the improvement of adsorption capacity by 39 times over the virgin OMC. Moreover, the Pb(II) adsorption results provided excellent fits to Langmuir model and pseudo-second-order kinetic model. The adsorption mechanism of Pb(II) onto MOMC-NP revealed the formation of metal complexes with carboxyl, hydroxyl, and phosphate groups through ion exchange reactions and hydrogen bondings. The calculated activation energy was 22.09 kJ/mol, suggesting that Pb(II) adsorption was a chemisorption. At pH>pH_pzc, the main Pb(II) existing species of Pb(II) and Pb(OH)⁺ combine with the carboxyl, hydroxyl, and phosphate functional groups via electrostatic interactions and hydrogen bonding. All these findings demonstrated that MOMC-NP could be a useful and potential adsorbent for adsorptive removal of Pb(II). Graphical abstract.

Keywords: Adsorption mechanism; Functionalized OMC; Lead (II) adsorption; Ordered mesoporous carbon (OMC); XPS analysis.

MeSH terms

Adsorption
Carbon*
Hydrogen-Ion Concentration
Kinetics
Lead
Solutions
Spectroscopy, Fourier Transform Infrared
Surface Properties
Water Pollutants, Chemical / analysis*

Substances

Solutions
Water Pollutants, Chemical
Lead
Carbon

Grants and funding

LEQSF (2016-17)-RD-C-15/Louisiana Board of Regents