Bioavailability and leaching of Cd and Pb from contaminated soil amended with different sizes of biochar

Biochars have been successfully used to reduce bioavailability and leaching of heavy metals in contaminated soils. The efficiency of biochar to immobilize heavy metals can be increased by reducing the particle size, which can increase the surface area and the cation exchange capacity (CEC). In this study, the empty fruit bunch biochar (EFBB) of oil palm was separated into two particle sizes, namely, fine (F-EFBB < 50 µm) and coarse (C-EFBB > 2 mm), to treat the contaminated soil with Cd and Pb. Results revealed that the addition of C-EFBB and F-EFBB increased the pH, electrical conductivity and CEC of the contaminated soil. The amounts of synthetic rainwater extractable and leachable Cd and Pb significantly decreased with the EFBB application. The lowest extractable and leachable Cd and Pb were observed from 1% F-EFBB-treated soil. The amount of extractable and leachable Cd and Pb decreased with increasing incubation times and leaching cycles. The application of F-EFBB to Cd and Pb-contaminated soil can immobilize the heavy metals more than that of C-EFBB. Therefore, the EFBB can be recommended for the remediation of heavy metal-contaminated soils, and a finer particle size can be applied at a lower application rate than the coarser biochar to achieve these goals.

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Land application technique for the treatment and disposal of sewage sludge

Water Science & Technology ◽

10.2166/wst.2002.0265 ◽

2002 ◽

Vol 46 (9) ◽

pp. 303-308 ◽

Cited By ~ 1

Author(s):

S.M. Zain ◽

H. Basri ◽

F. Suja' ◽

O. Jaafar

Keyword(s):

Heavy Metals ◽

Sewage Sludge ◽

Cation Exchange ◽

Cation Exchange Capacity ◽

Chemical Properties ◽

Potential Effect ◽

Application Rate ◽

Exchange Capacity ◽

Land Application ◽

Treated Soil

Some of the major concerns when applying sewage sludge to land include the potential effect on pH and cation exchange capacity; the mobility and the accumulation of heavy metals in sludge treated soil; the potential of applying too much nutrients and the problems associated with odors and insects. The main objective of this study is to identify the effects of sewage sludge application on the physical and chemical properties of sludge treated soil. Sewage sludge was applied to soil at various rates ranging from 0 L/m2 to 341 L/m2. In order to simulate the natural environment, the study was carried out at a pilot treatment site (5.2 m × 6.7 m) in an open area, covered with transparent roofing material to allow natural sunlight to pass through. Simulated rain was applied by means of a sprinkler system. Data obtained from sludge treated soil showed that the pH values decreased when the application rates were increased and the application period prolonged. The effect of sewage sludge on cation exchange capacity was not so clear; the values obtained for every application rate of sewage sludge did not indicate any consistent behaviour. The mobility of heavy metals in soils treated with sludge were described by observing the changes in the concentration of the heavy metals. The study showed that Cd has the highest mobility in sludge treated soil followed by Cu, Cr, Zn, Ni and Pb.

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Effects of Phosphate Rock on Absorption and Accumulation of Heavy Metals of Ryegrass in Heavy Metal Contaminated Soil

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.522-524.752 ◽

2014 ◽

Vol 522-524 ◽

pp. 752-757 ◽

Cited By ~ 1

Author(s):

Ying Zhe Wang ◽

Zhong Qiu Zhao ◽

Guang Yu Jiang

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Perennial Ryegrass ◽

Significant Influence ◽

Contaminated Soil ◽

Contaminated Soils ◽

Phosphate Rock ◽

Particle Sizes ◽

Cu And Zn ◽

Soil Weight

The effects of phosphates rock (PR) with different particle sizes {D97<4.26 (the diameters of 97% of the particles are less than 4.26 µm.), <36.83, <71.12 and <101.43 µm} and different concentration (2.5% and 5% content of try soil weight) on immobilizing heavy metal-contaminated soils by a perennial ryegrass greenhouse experiment are conducted. Results indicate that remediation effect of applying 5% content is more significant than 2.5%. Ryegrass biomass in shoots in the former applying content is much larger than the latter and for both roots and shoots, PR reduces the absorption and accumulation of Pb, Cu and Zn, but no significant influence on Cd. While adding the same amount of different sizes of PR doesn’t show significant differences between these treatments. Pb content at 5% level of the finest size of PR is the minimum, decreased by 33% and 56% compared to the control in roots and shoots respectively, which was also suitable for Zn, decreased by 12.65% and 39.61% respectively.

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Clinoptilolitic Zeolite as an Amendment for Establishment of Creeping Bentgrass on Sandy Media

HortScience ◽

10.21273/hortsci.26.2.117 ◽

1991 ◽

Vol 26 (2) ◽

pp. 117-119 ◽

Cited By ~ 19

Author(s):

J.L. NUS ◽

S.E. Brauen

Keyword(s):

Particle Size ◽

Cation Exchange ◽

Cation Exchange Capacity ◽

Creeping Bentgrass ◽

Ammonium Nitrogen ◽

Exchange Capacity ◽

Particle Sizes ◽

Agrostis Palustris ◽

Exchangeable Potassium ◽

Sphagnum Peat

In a field experiment, clinoptilolitic zeolite was compared to sphagnum peat and sawdust as sand amendments at 5%, 10%, and 209” (v/v) to enhance `Penncross' creeping bentgrass (Agrostis palustris Huds.) establishment and to compare their gravimetric and volumetric cation exchange capacities and their effects on moisture retention and cation exchange capacities of the resultant mixes. In addition, cation exchange capacities and exchangeable K+ and \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{NH}_{4}^{+}\) \end{document}; were analyzed from clinoptilolitic zeolite of particle sizes ranging from <0.25 mm to >5.0 mm. All amendments, except 10?ZO and 20% sawdust, resulted in superior establishment compared to unamended sand. Peat-amended sand retained significantly more moisture than sawdust- or zeolite-amended sand at –6, –10, –33, and -250 kpa soil matric potentials. Zeolite exhibited a much higher volumetric cation exchange capacity than either sawdust or sphagnum peat. Cation exchange capacity and exchangeable potassium of clinoptilolitic zeolite was greatest when particle size was <0.5 mm; however, little exchangeable ammonium nitrogen was detected.

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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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The Effect of Gasification Conditions on the Surface Properties of Biochar Produced in a Top-Lit Updraft Gasifier

Applied Sciences ◽

10.3390/app10020688 ◽

2020 ◽

Vol 10 (2) ◽

pp. 688 ◽

Cited By ~ 3

Author(s):

Arthur M. James R. ◽

Wenqiao Yuan ◽

Duo Wang ◽

Donghai Wang ◽

Ajay Kumar

Keyword(s):

Particle Size ◽

Moisture Content ◽

Surface Properties ◽

Functional Groups ◽

Cation Exchange Capacity ◽

Functional Group ◽

Exchange Capacity ◽

Low Ph ◽

Airflow Rate ◽

Particle Sizes

The effect of airflow rate, biomass moisture content, particle size, and compactness on the surface properties of biochar produced in a top-lit updraft gasifier was investigated. Pine woodchips were studied as the feedstock. The carbonization airflow rates from 8 to 20 L/min were found to produce basic biochars (pH > 7.0) that contained basic functional groups. No acid functional groups were presented when the airflow increased. The surface charge of biochar at varying airflow rates showed that the cation exchange capacity increased with airflow. The increase in biomass moisture content from 10 to 14% caused decrease in the pH from 12 to 7.43, but the smallest or largest particle sizes resulted in low pH; therefore, the carboxylic functional groups increased. Similarly, the biomass compactness exhibited a negative correlation with the pH that reduced with increasing compactness level. Thus, the carboxylic acid functional groups of biochar increased from 0 to 0.016 mmol g−1, and the basic functional group decreased from 0.115 to 0.073 mmol g−1 when biomass compactness force increased from 0 to 3 kg. BET (Brunauer-Emmett-Teller) surface area of biochar was greater at higher airflow and smaller particle size, lower moisture content, and less compactness of the biomass.

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Effect of different soil and weather conditions on efficacy, selectivity and dissipation of herbicides in sunflower

Plant Soil and Environment ◽

10.17221/223/2020-pse ◽

2020 ◽

Vol 66 (No. 9) ◽

pp. 468-476

Author(s):

Miroslav Jursík ◽

Martin Kočárek ◽

Michaela Kolářová ◽

Lukáš Tichý

Keyword(s):

Cation Exchange Capacity ◽

Chenopodium Album ◽

Soil Layer ◽

Weather Conditions ◽

Growing Season ◽

Application Rate ◽

Exchange Capacity ◽

Vertical Transport ◽

Application Rates ◽

High Precipitation

Six sunflower herbicides were tested at two application rates (1N and 2N) on three locations (with different soil types) within three years (2015–2017). Efficacy of the tested herbicides on Chenopodium album increased with an increasing cation exchange capacity (CEC) of the soil. Efficacy of pendimethalin was 95%, flurochloridone and aclonifen 94%, dimethenamid-P 72%, pethoxamid 49% and S-metolachlor 47%. All tested herbicides injured sunflower on sandy soil (Regosol) which had the lowest CEC, especially in wet conditions (phytotoxicity 27% after 1N application rate). The highest phytotoxicity was recorded after the application of dimethenamid-P (19% at 1N and 45% at 2N application rate). Main symptoms of phytotoxicity were leaf deformations and necroses and the damage of growing tips, which led to destruction of some plants. Aclonifen, pethoxamid and S-metolachlor at 1N did not injure sunflower on the soil with the highest CEC (Chernozem) in any of the experimental years. Persistence of tested herbicides was significantly longer in Fluvisol (medium CEC) compared to Regosol and Chernozem. Dimethenamid-P showed the shortest persistence in Regosol and Chernozem. The majority of herbicides was detected in the soil layer 0–5 cm in all tested soils. Vertical transport of herbicides in soil was affected by the herbicide used, soil type and weather conditions. The highest vertical transport was recorded for dimethenamid-P and pethoxamid (4, resp. 6% of applied rate) in Regosol in the growing season with high precipitation.

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Fractionation of Heavy Metals in Multi-Contaminated Soil Treated with Biochar Using the Sequential Extraction Procedure

Biomolecules ◽

10.3390/biom11030448 ◽

2021 ◽

Vol 11 (3) ◽

pp. 448

Author(s):

Mahrous Awad ◽

Zhongzhen Liu ◽

Milan Skalicky ◽

Eldessoky S. Dessoky ◽

Marian Brestic ◽

...

Keyword(s):

Heavy Metals ◽

Organic Matter ◽

Soil Organic Matter ◽

Soil Ph ◽

Contaminated Soil ◽

Contaminated Soils ◽

Extraction Procedure ◽

Sequential Fractionation ◽

Relationship Of ◽

The Relationship

Heavy metals (HMs) toxicity represents a global problem depending on the soil environment’s geochemical forms. Biochar addition safely reduces HMs mobile forms, thus, reducing their toxicity to plants. While several studies have shown that biochar could significantly stabilize HMs in contaminated soils, the study of the relationship of soil properties to potential mechanisms still needs further clarification; hence the importance of assessing a naturally contaminated soil amended, in this case with Paulownia biochar (PB) and Bamboo biochar (BB) to fractionate Pb, Cd, Zn, and Cu using short sequential fractionation plans. The relationship of soil pH and organic matter and its effect on the redistribution of these metals were estimated. The results indicated that the acid-soluble metals decreased while the fraction bound to organic matter increased compared to untreated pots. The increase in the organic matter metal-bound was mostly at the expense of the decrease in the acid extractable and Fe/Mn bound ones. The highest application of PB increased the organically bound fraction of Pb, Cd, Zn, and Cu (62, 61, 34, and 61%, respectively), while the BB increased them (61, 49, 42, and 22%, respectively) over the control. Meanwhile, Fe/Mn oxides bound represents the large portion associated with zinc and copper. Concerning soil organic matter (SOM) and soil pH, as potential tools to reduce the risk of the target metals, a significant positive correlation was observed with acid-soluble extractable metal, while a negative correlation was obtained with organic matter-bound metal. The principal component analysis (PCA) shows that the total variance represents 89.7% for the TCPL-extractable and HMs forms and their relation to pH and SOM, which confirms the positive effect of the pH and SOM under PB and BB treatments on reducing the risk of the studied metals. The mobility and bioavailability of these metals and their geochemical forms widely varied according to pH, soil organic matter, biochar types, and application rates. As an environmentally friendly and economical material, biochar emphasizes its importance as a tool that makes the soil more suitable for safe cultivation in the short term and its long-term sustainability. This study proves that it reduces the mobility of HMs, their environmental risks and contributes to food safety. It also confirms that performing more controlled experiments, such as a pot, is a disciplined and effective way to assess the suitability of different types of biochar as soil modifications to restore HMs contaminated soil via controlling the mobilization of these minerals.

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Researches on the accumulation and transfer of heavy metals in the soil in tomatoes -Solanum lycopersicum

E3S Web of Conferences ◽

10.1051/e3sconf/201911203020 ◽

2019 ◽

Vol 112 ◽

pp. 03020

Author(s):

Mihaela Niţu ◽

Augustina Pruteanu ◽

Despina Maria Bordean ◽

Carmen Popescu ◽

Gyorghy Deak ◽

...

Keyword(s):

Heavy Metals ◽

Transfer Coefficient ◽

Human Body ◽

Contaminated Soil ◽

Contaminated Soils ◽

Tomato Fruit ◽

Human Consumption ◽

Tomato Fruits ◽

Lead And Zinc ◽

Copper Lead

Heavy metals in contaminated soils have benefited from a considerable attention due to the possible risks for the human body. The current study has investigated the accumulation and transfer coefficient for three heavy metals (Cu, Pb, Zn) found in the contaminated soil with three concentrations (c1=1.5%, c2=3.0%, c3=4.5%, c4=6.0%), obtained by mixing the three metals, in the tomato fruit. The highest accumulation in the tomato fruits was recorded for zinc, then copper and the smallest for lead, for all four concentrations used. The transfer coefficient decreases as the concentration of heavy metals increases, so that for high heavy metals concentrations, the values of the transfer coefficient are very low, and for small heavy metals concentrations in the soil, the values for the transfer coefficient are higher. The assessment of accumulation and transfer of heavy metals in the fruits of tomatoes grown in the contaminated soil has concluded that all concentrations of the copper, lead and zinc mix have shown a low risk for human consumption.

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Effect of Soil Washing Solutions on Simultaneous Removal of Heavy Metals and Arsenic from Contaminated Soil

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17093133 ◽

2020 ◽

Vol 17 (9) ◽

pp. 3133 ◽

Cited By ~ 1

Author(s):

Kanghee Cho ◽

Eunji Myung ◽

Hyunsoo Kim ◽

Cheonyoung Park ◽

Nagchoul Choi ◽

...

Keyword(s):

Heavy Metals ◽

Sulfuric Acid ◽

Phosphoric Acid ◽

Contaminated Soil ◽

Contaminated Soils ◽

Soil Washing ◽

Metal Extraction ◽

Simultaneous Removal ◽

Removal Of Heavy Metals ◽

Removal Efficiencies

In this study, we investigated the feasibility of using a solution of sulfuric acid and phosphoric acid as an extraction method for soil-washing to remove Cu, Pb, Zn, and As from contaminated soil. We treated various soil particles, including seven fraction sizes, using sulfuric acid. In addition, to improve Cu, Pb, Zn, and As removal efficiencies, washing agents were compared through batch experiments. The results showed that each agent behaved differently when reacting with heavy metals (Cu, Pb, and Zn) and As. Sulfuric acid was more effective in extracting heavy metals than in extracting As. However, phosphoric acid was not effective in extracting heavy metals. Compared with each inorganic acid, As removal from soil by washing agents increased in the order of sulfuric acid (35.81%) < phosphoric acid (62.96%). Therefore, an enhanced mixture solution using sulfuric acid and phosphoric acid to simultaneously remove heavy metals and As from contaminated soils was investigated. Sulfuric acid at 0.6 M was adopted to combine with 0.6 M phosphoric acid to obtain the mixture solution (1:1) that was used to determine the effect for the simultaneous removal of both heavy metals and As from the contaminated soil. The removal efficiencies of As, Cu, Pb, and Zn were 70.5%, 79.6%, 80.1%, and 71.2%, respectively. The combination of sulfuric acid with phosphoric acid increased the overall As and heavy metal extraction efficiencies from the contaminated soil samples. With the combined effect of dissolving oxides and ion exchange under combined washings, the removal efficiencies of heavy metals and As were higher than those of single washings.

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Evaluation of Acid Leaching on the Removal of Heavy Metals and Soil Fertility in Contaminated Soil

Journal of Chemistry ◽

10.1155/2018/5036581 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Chen-Yao Chu ◽

Tzu-Hsing Ko

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Seed Germination ◽

Soil Fertility ◽

Sequential Extraction ◽

Contaminated Soil ◽

Contaminated Soils ◽

Germination Rate ◽

Extraction Procedure ◽

Acid Leaching

Heavy metal-contaminated soils were leached with various acid reagents, and a series of treatments was assessed to understand soil fertility after acid leaching. Aqua regia digestion and a five-step sequential extraction procedure were applied to determine heavy metal distribution. The average total concentrations of Zn, Cd, Cu, and Pb for contaminated soil were 1334, 25, 263, and 525 mg·kg−1 based on the ICP/AES quantitative analysis. Other than Pb extracted by H2SO4, over 50% removal efficiency of other heavy metals was achieved. A five-step sequential extraction revealed that the bound-to-carbonate and bound-to-Fe-Mn oxides were the major forms of the heavy metals in the soil. The addition of organic manure considerably promoted soil fertility and increased soil pH after acid leaching. Seed germination experiments demonstrated that after acid leaching, the soil distinctly inhibited plant growth and the addition of manure enhanced seed germination rate from 35% to 84%. Furthermore, the procedure of soil turnover after acid leaching and manure addition greatly increased seed germination rate by 61% and shortened the initial germination time. Seed germination in untreated soil was superior to that in acid-leached soil, illustrating that the phytotoxic effect of acid leaching is more serious than that of heavy metals.

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