TY - JOUR
T1 - Lead (Pb) sorption to hydrophobic and hydrophilic zeolites in the presence and absence of MTBE
AU - Zhang, Yunhui
AU - Alessi, Daniel S.
AU - Chen, Ning
AU - Luo, Mina
AU - Hao, Weiduo
AU - Alam, Md Samrat
AU - Flynn, Shannon L.
AU - Kenney, Janice P.L.
AU - Konhauser, Kurt O.
AU - Ok, Yong Sik
AU - Al-Tabbaa, Abir
N1 - Funding Information:
The first author is grateful to the China Scholarship Council (CSC) for a PhD studentship. This study was financially supported by the Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery grants to DSA ( RGPIN-04134 ) and KOK ( RGPIN-165831 ).
Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/10/15
Y1 - 2021/10/15
N2 - The co-contamination of the environment by metals and organic pollutants is a significant concern, and one such example is lead (Pb) and methyl tert-butyl ether (MTBE) due to their historic use as fuel additives. Clinoptilolite is an abundant and efficient zeolite for metal removal, but the potential interference of co-existing organic pollutants on metal removal, such as MTBE, have rarely been discussed. In this study, a combination of batch sorption tests and synchrotron-based X-ray absorption spectroscopic analyses were employed to investigate Pb sorption mechanism(s) onto clinoptilolite in the presence and absence of MTBE. A comparison was made to synthetic ZSM-5 zeolite to gain insights into differences in Pb binding mechanisms between hydrophilic (clinoptilolite) and hydrophobic (ZSM-5) zeolites. Site occupancy and surface precipitation contributed equally to Pb removal by clinoptilolite, while surface precipitation was the main Pb removal mechanism for ZSM-5 followed by site occupancy. Despite the negligible effect of 100 mg/L MTBE on observed Pb removal from solution by both zeolites, a surface-embedded Pb removal mechanism, through the Mg site on clinoptilolite surface, arises when MTBE is present. This study provides an understanding of atomic-level Pb uptake mechanisms on zeolites, with and without co-contaminating MTBE, which aids in their application in water treatment at co-contaminated sites.
AB - The co-contamination of the environment by metals and organic pollutants is a significant concern, and one such example is lead (Pb) and methyl tert-butyl ether (MTBE) due to their historic use as fuel additives. Clinoptilolite is an abundant and efficient zeolite for metal removal, but the potential interference of co-existing organic pollutants on metal removal, such as MTBE, have rarely been discussed. In this study, a combination of batch sorption tests and synchrotron-based X-ray absorption spectroscopic analyses were employed to investigate Pb sorption mechanism(s) onto clinoptilolite in the presence and absence of MTBE. A comparison was made to synthetic ZSM-5 zeolite to gain insights into differences in Pb binding mechanisms between hydrophilic (clinoptilolite) and hydrophobic (ZSM-5) zeolites. Site occupancy and surface precipitation contributed equally to Pb removal by clinoptilolite, while surface precipitation was the main Pb removal mechanism for ZSM-5 followed by site occupancy. Despite the negligible effect of 100 mg/L MTBE on observed Pb removal from solution by both zeolites, a surface-embedded Pb removal mechanism, through the Mg site on clinoptilolite surface, arises when MTBE is present. This study provides an understanding of atomic-level Pb uptake mechanisms on zeolites, with and without co-contaminating MTBE, which aids in their application in water treatment at co-contaminated sites.
KW - Advanced spectroscopic analysis
KW - Clean water and sanitation
KW - Sorbent
KW - Surface coating
KW - Zeolite
UR - http://www.scopus.com/inward/record.url?scp=85109658166&partnerID=8YFLogxK
U2 - 10.1016/j.jhazmat.2021.126528
DO - 10.1016/j.jhazmat.2021.126528
M3 - Article
C2 - 34265651
AN - SCOPUS:85109658166
VL - 420
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
SN - 0304-3894
M1 - 126528
ER -
