Optimization and mechanism of the novel eco-friendly additives for solidification and stabilization of dredged sediment

Deng, Yu-Jia; Yue, Zhi-Xuan; Wang, Zi-Jie; Huang, Qi; Yang, Xiao-Li

doi:10.1007/s11356-024-32865-2

Cited by 1 publication

(1 citation statement)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Solidification/stabilization (S/S) has been broadly utilized to immobilize contaminants and improve soil characteristics. This process is implemented by introducing a binding agent into the contaminated site through which the mobility (or toxicity) of HMs is reduced, and they become encapsulated into a monolithic solid with a minor surface area (Deng et al 2024 ). In the S/S process, lime (CaO or Ca(OH)2) and Portland cement are the most often utilized binders (Chen et al 2023 ).…”

Section: Introductionmentioning

confidence: 99%

Solidification/stabilization of lead-contaminated soil using alkali-activated volcanic ash

Molaei,

Miraki,

Morovati

et al. 2024

Environ Sci Pollut Res

View full text Add to dashboard Cite

The bioaccumulation of lead in soil poses a significant human health risk. The solidification/stabilization (S/S) technique, employing binders like Portland cement or lime, is a common method for remediating lead-contaminated soil. However, cement production has adverse environmental impacts, prompting the exploration of eco-friendly alternatives like alkali-activated materials (AAMs). This study assesses AAM efficacy in the S/S of lead-contaminated soil. The effects of several factors, including varying amounts of volcanic ash (VA), lead concentration, curing temperatures, and curing times are investigated. Unconfined compressive strength (UCS), toxicity characteristic leaching procedure test (TCLP), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and field emission scanning electron microscope-energy-dispersive spectroscopy-mapping analyses (FESEM/EDS/mapping) analyses are used to study the specimens. The findings indicated a substantial increase in the UCS of lead-contaminated soil treated with 15% VA (under oven curing (OC) conditions), and 10% VA (under ambient curing (AC) conditions) exhibited remarkable increases of up to 600% and 458%, respectively. Moreover, the leaching of Pb2+ ions from samples contaminated with 10,000 mg/kg (under OC conditions) and 2500 mg/kg (under AC conditions) experienced significant reductions of 87% (from 135.14 to 13.36 ppm) and 91% (from 26.32 to 2.21 ppm), respectively. The S/S process in these samples operated through three primary mechanisms of chemical bonding, physical encapsulation, and the formation of insoluble silicate. The formation of N-A-S–H and hydroxy sodalite structures played a vital role in facilitating these mechanisms. Therefore, alkali-activated VA demonstrated excellent performance in the remediation of lead-contaminated soil. Graphical Abstract

show abstract

Section: Introductionmentioning

confidence: 99%