Metal immobilization and phosphorus leaching after stabilization of pyrite ash contaminated soil by phosphate amendments

Soil amendments have been proposed for immobilizing metallic contaminants, thus reducing their uptake by plants. For the safe production of crops in contaminated soil, there is a need to select suitable amendments that can mitigate heavy metal uptake and enhance crop yield. The present experiment compared the effects of three amendments, hydroxyapatite (HAP), organic manure (OM), and biochar (BC), on plant growth and heavy metal accumulation by maize in an acidic soil contaminated with Cd, Pb, and Zn, and their potential for safe crop production. Toxicity characteristic leaching procedure (TCLP) tests, energy dispersive X-ray spectroscopy (EDS) analysis, and X-ray diffraction (XRD) analysis were used to evaluate the effectiveness and mechanisms of heavy metal immobilization by the amendments. The results showed that shoot and root biomass was significantly increased by HAP and 1% OM, with an order of 1% HAP > 0.1% HAP > 1% OM, but not changed by 0.1% OM and BC (0.1% and 1%). HAP significantly decreased Cd, Pb, and Zn concentrations in both shoots and roots, and the effects were more pronounced at the higher doses. OM decreased the shoot Cd and Pb concentrations and root Zn concentrations, but only 1% OM decreased the shoot Zn and root Pb concentrations. BC decreased the shoot Cd and Pb concentrations, but decreased the shoot Zn and root Pb concentrations only at 1%. HAP decreased the translocation factors (TFs) of Cd, Pb, and Zn (except at the 0.1% dose). OM and BC decreased the TFs of Cd and Zn, respectively, at the 1% dose but showed no significant effects in other cases. Overall, plant P, K, Fe, and Cu nutrition was improved by HAP and 1% OM, but not by 0.1 OM and BC. Soil pH was significantly increased by HAP, 1% OM, and 1% BC, following an order of 1% HAP > 1% OM > 0.1% HAP > 1% BC. The TCLP levels for Cd, Pb, and Zn were significantly reduced by HAP, which can be partly attributed to its liming effects and the formation of sparingly soluble Cd-, Pb-, and Zn-P-containing minerals in the HAP-amended soils. To some extent, all the amendments positively influenced plant and soil traits, but HAP was the optimal one for stabilizing heavy metals, reducing heavy metal uptake, and promoting plant growth in the contaminated soil, suggesting its potential for safe crop production.

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Remediation of Contaminated Soil by Amendment of Nonhumus Soil with Humus-Rich Soil for Better Metal Immobilization

Bulletin of Environmental Contamination and Toxicology ◽

10.1007/s00128-004-0465-2 ◽

2004 ◽

Vol 73 (3) ◽

Cited By ~ 7

Author(s):

V. Misra ◽

S. D. Pandey

Keyword(s):

Contaminated Soil ◽

Metal Immobilization

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Biochar application to metal-contaminated soil: Evaluating of Cd, Cu, Pb and Zn sorption behavior using single- and multi-element sorption experiment

Plant Soil and Environment ◽

10.17221/155/2011-pse ◽

2011 ◽

Vol 57 (No. 8) ◽

pp. 372-380 ◽

Cited By ~ 51

Author(s):

L. Trakal ◽

M. Komárek ◽

J. Száková ◽

V. Zemanová ◽

P. Tlustoš

Keyword(s):

Contaminated Soil ◽

Contaminated Soils ◽

Organic Material ◽

Application Rate ◽

Sorption Behavior ◽

Competition Effect ◽

Sorption Experiment ◽

Application Rates ◽

Metal Immobilization ◽

Different Types

The aim of this study was to evaluate metals (Cd, Cu, Pb and Zn) sorption behavior after biochar application into a metal-contaminated soil. Additionally, two different types of biochar originated from the same organic material (contaminated and uncontaminated) at different application rates (1% and 2% w/w) were evaluated as a novelty of the experiment. Batch sorption/desorption experiments were established to compare the sorption behavior of metals originating from single- and multi-element solutions. Zinc as one of the main contaminants in the studied soil was easily desorbed in the presence of Cu, Pb and to a lesser extent by Cd. This desorption was reduced after biochar application. The obtained results proved the different sorption behavior of metals in the single-metal solution compared to the multi-metal ones due to competition effect. Moreover, during multi-element sorption, Zn was significantly desorbed. The applied biochar enhanced Cu and Pb sorption and no changes were observed when contaminated and uncontaminated biochar was used. Furthermore, the application rate (1% and 2% w/w) had no effect as well. In summary, it is needed to point out that the applied rates of biochars were insufficient for metal immobilization in such contaminated soils.

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Heavy metal immobilization by cost-effective amendments in a contaminated soil: Effects on metal leaching and phytoavailability

Journal of Geochemical Exploration ◽

10.1016/j.gexplo.2011.10.004 ◽

2012 ◽

Vol 123 ◽

pp. 87-94 ◽

Cited By ~ 138

Author(s):

David Houben ◽

Jonathan Pircar ◽

Philippe Sonnet

Keyword(s):

Heavy Metal ◽

Contaminated Soil ◽

Cost Effective ◽

Metal Leaching ◽

Metal Immobilization ◽

Heavy Metal Immobilization ◽

Soil Effects

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Application of Biochar in the Remediation of Contaminated Soil with High Concentration of Lead and Zinc

Advances in Civil Engineering ◽

10.1155/2021/6630982 ◽

2021 ◽

Vol 2021 ◽

pp. 1-7

Author(s):

Xiaoming Zhao ◽

Binbin Yang ◽

Yuan Li ◽

Dongqi Tang ◽

Ke Xu ◽

...

Keyword(s):

Contaminated Soil ◽

Hunan Province ◽

Control Group ◽

High Concentration ◽

Severe Problem ◽

Treated Soil ◽

Mining Areas ◽

Lead And Zinc ◽

Metal Immobilization ◽

Heavy Metal Immobilization

Soil contamination in the Panjiachong lead and zinc mining areas has become a severe problem in Hunan Province, China. As the traditional stabilization technology comes with soil degradation, it is urgent to find a novel binder that is more eco-friendly. It has been proved that biochar can immobilize heavy metals, but limited research has been conducted on the contaminated soil with high concentration. In this study, 5%, 8%, and 10% biochar derived from the rice straw were used to remediate contaminated soil with high concentration of lead and zinc. Portland cement (PC) was adopted as the control group. The results showed that after 56 d curing, the biochar-treated soil had a neutral pH and EC value and higher soil fertility compared with the PC-treated soil. The results from the toxicity characteristic leaching procedure test indicated that the biochar is more effective than PC on heavy metal immobilization. Germination index (GI) value was used to evaluate the phytotoxicity of the treated soil; the GI values of treated soil with 8% and 10% biochar were both higher than 80%, while all the PC-treated groups failed to achieve this GI value, which indicated the potential revegetation is applicable for the biochar-treated soil.

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The Research of Nanoparticle and Microparticle Hydroxyapatite Amendment in Multiple Heavy Metals Contaminated Soil Remediation

Journal of Nanomaterials ◽

10.1155/2014/168418 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 12

Author(s):

Zhangwei Li ◽

Man-man Zhou ◽

Weidian Lin

Keyword(s):

Particle Size ◽

Contaminated Soil ◽

Contaminated Soils ◽

Particle Sizes ◽

Micrometer Particle ◽

Metal Immobilization ◽

Sequential Extraction Method ◽

Multiple Heavy Metals ◽

Nanometer Particle

It was believed that when hydroxyapatite (HAP) was used to remediate heavy metal-contaminated soils, its effectiveness seemed likely to be affected by its particle size. In this study, a pot trial was conducted to evaluate the efficiency of two particle sizes of HAP: nanometer particle size of HAP (nHAP) and micrometer particle size of HAP (mHAP) induced metal immobilization in soils. Both mHAP and nHAP were assessed for their ability to reduce lead (Pb), zinc (Zn), copper (Cu), and chromium (Cr) bioavailability in an artificially metal-contaminated soil. The pakchoi (Brassica chinensisL.) uptake and soil sequential extraction method were used to determine the immobilization and bioavailability of Pb, Zn, Cu, and Cr. The results indicated that both mHAP and nHAP had significant effect on reducing the uptake of Pb, Zn, Cu, and Cr by pakchoi. Furthermore, both mHAP and nHAP were efficient in covering Pb, Zn, Cu, and Cr from nonresidual into residual forms. However, mHAP was superior to nHAP in immobilization of Pb, Zn, Cu, and Cr in metal-contaminated soil and reducing the Pb, Zn, Cu, and Cr utilized by pakchoi. The results suggested that mHAP had the better effect on remediation multiple metal-contaminated soils than nHAP and was more suitable for applying inin situremediation technology.

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