Ibrahim, H.M.; Al-Issa, A.A.; Al-Farraj, A.S.; Alghamdi, A.G.; Al-Turki, A.M. Effect of Stabilized NZVI Nanoparticles on the Reduction and Immobilization of Cr in Contaminated Soil: Column Experiment and Transport Modeling. Nanomaterials 2024, 14, 862, doi:10.3390/nano14100862.
Ibrahim, H.M.; Al-Issa, A.A.; Al-Farraj, A.S.; Alghamdi, A.G.; Al-Turki, A.M. Effect of Stabilized NZVI Nanoparticles on the Reduction and Immobilization of Cr in Contaminated Soil: Column Experiment and Transport Modeling. Nanomaterials 2024, 14, 862, doi:10.3390/nano14100862.
Ibrahim, H.M.; Al-Issa, A.A.; Al-Farraj, A.S.; Alghamdi, A.G.; Al-Turki, A.M. Effect of Stabilized NZVI Nanoparticles on the Reduction and Immobilization of Cr in Contaminated Soil: Column Experiment and Transport Modeling. Nanomaterials 2024, 14, 862, doi:10.3390/nano14100862.
Ibrahim, H.M.; Al-Issa, A.A.; Al-Farraj, A.S.; Alghamdi, A.G.; Al-Turki, A.M. Effect of Stabilized NZVI Nanoparticles on the Reduction and Immobilization of Cr in Contaminated Soil: Column Experiment and Transport Modeling. Nanomaterials 2024, 14, 862, doi:10.3390/nano14100862.
Abstract
Batch and transport experiments were used to investigate the remediation of a loamy sand soil contaminated with Cr(VI) using zero valent iron nanoparticles (nZVI) stabilized by the carboxy methyl cellulose (CMC-nZVI). The effect of pH, ionic strength (IS), and flow rate on the removal efficiency of Cr(VI) were investigated under equilibrium (uniform transport) and non-equilibrium (Two-site sorption) transport using the Hydrus-1D model. The overall removal efficiency ranged from 70 to over 90% based on the chemical characteristics of the CMC-nZVI suspension and the transport conditions. The concentration and pH of the CMC-nZVI suspension had the most significant effect on the removal efficiency and transport of Cr(VI) in the soil. The average removal efficiency of Cr(VI) was increased from 24.1 to 75.5% when the concentration of CMC-nZVI nanoparticles was increased from 10 to 250 mg L-1, mainly because of the increased total surface area at larger particle concentration. Batch experiments showed that removal efficiency of Cr(VI) was much larger under acidic conditions. The average removal efficiency of Cr(VI) reached 90.1 and 60.5 % at pH 5 and 7, respectively. The Two-site sorption model described quite well (r2 = 0.96-0.98) the transport of Cr(VI) in soil as compared to the uniform transport model (r2 = 0.81-0.98). The average retardation of Cr(VI) was 3.51 and 1.61 at pH 5 and 7, respectively, indicating earlier arrival for the breakthrough curves and shorter time to reach maximum relative concentration at lower pH. The Hydrus-1D model has proven to be an efficient tool for assessing the removal of Cr(VI) pollutants, offering innovative, cost-effective, and environmentally friendly remediation methodologies.
Keywords
Nanosized zero valent iron (nZVI); heavy metals; soil contamination; transport modeling
Subject
Environmental and Earth Sciences, Pollution
Copyright:
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