Surface modification of quartz sand: A review of its progress and its effect on heavy metal adsorption

Ting Wang; Weiyuan Cao; Yingqi Wang; Chao Qu; Yufeng Xu; Haixiang Li

doi:10.1016/j.ecoenv.2023.115179

Surface modification of quartz sand: A review of its progress and its effect on heavy metal adsorption

Ecotoxicol Environ Saf. 2023 Jun 23:262:115179. doi: 10.1016/j.ecoenv.2023.115179. Online ahead of print.

Authors

Ting Wang¹, Weiyuan Cao¹, Yingqi Wang¹, Chao Qu², Yufeng Xu³, Haixiang Li⁴

Affiliations

¹ Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541006, China; Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin 541006, China.
² Handan Environmental Monitoring Center Station, Handan 056000, China.
³ Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541006, China; Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin 541006, China; Chinese Acad Sci, Res Ctr Ecoenvironm Sci, Beijing 100085, China. Electronic address: jackstarfly@126.com.
⁴ Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541006, China; Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin 541006, China. Electronic address: lihaixiang0627@163.com.

PMID: 37356400
DOI: 10.1016/j.ecoenv.2023.115179

Abstract

Quartz sand (SiO₂) is a prevalent filtration medium, boasting wide accessibility, superior stability, and cost-effectiveness. However, its utility is often curtailed by its sleek surface, limited active sites, and swift saturation of adsorption sites. This review outlines the prevalent strategies and agents for quartz sand surface modification and provides a comprehensive analysis of the various modification reagents and their operative mechanisms. It delves into the mechanism and utility of surface-modified quartz sand for adsorbing heavy metal ions (HMIs). It is found that the reported modifiers usually form connections with the surface of quartz sand through electrostatic forces, van der Waals forces, pore filling, chemical bonding, and/or molecular entanglement. The literature suggests that these modifications effectively address issues inherent to natural quartz sand, such as its low superficial coarseness, rapid adsorption site saturation, and limited adsorption capacity. Regrettably, comprehensive investigations into the particle size, regenerative capabilities, and application costs of surface-modified quartz sand and the critical factors for its wider adoption are lacking in most reports. The adsorption mechanisms indicate that surface-modified quartz sand primarily removes HMIs from aqueous solutions through surface complexation, ion exchange, and electrostatic and gravitational forces. However, these findings were derived under controlled laboratory conditions, and practical applications for treating real wastewater necessitate overcoming further laboratory-scale obstacles. Finally, this review outlines the limitations of partially surface modified quartz sand and suggests potential venues for future developments, providing a valuable reference for the advancement of cost-effective, HMI-absorbing, surface-modified quartz sand filter media.

Keywords: Adsorption mechanism; Heavy metal ions (HMIs); Modification mechanism; Natural quartz sand; Surface-modified quartz sand.

Publication types

Review