Innovative Technologies for Soil and Water Remediation

A special issue of Water (ISSN 2073-4441). This special issue belongs to the section "Soil and Water".

Deadline for manuscript submissions: closed (30 June 2023) | Viewed by 22925

Special Issue Editors


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Guest Editor
Wuhan Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, China
Interests: polluted soil; leaching action; solute migration; heavy metal pollution; environmental protection
Special Issues, Collections and Topics in MDPI journals
Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
Interests: engineered biochar; soil remediation; sustainable waste management; geochemistry; environmental mineralogy
Special Issues, Collections and Topics in MDPI journals
Institute of Geotechnical Engineering, School of Transportation, Southeast University, Nanjing, China
Interests: soil respiration; environmental engineering; environmental pollution; soil remediation; biochar; environmental impact assessment; phytoremediation; water quality
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Soil and water remediation are considered as last frontiers in the field of environmental remediation due to the intricate, uncertain fate and transport of contaminants in environmental medias and consequent huge cost and unsatisfying effects. With the grown concern of water and soil contamination and technological development, the deficiencies and even hazards of traditional amendments have gradually been discovered. From this perspective, innovative technologies and methodologies, such as accurate mapping of contaminants distribution, targeted and eco-friendly amendments and comprehensive and scientific evaluation of remediation effect, are indispensable and instant for establishing the whole process management and quality control system of soil and water remediation. However, a series of research gap stilled remains to be filled and therefore, this Special Issue of Water focuses on the current progress and future perspectives of innovative technologies in the field of soil and water remediation. The section of soil and water mainly covers research papers, reviews, case reports and conference paper. In addition, research in the field of fate and transport research, prediction and accurate mapping of contaminants, design, characterization, modification of innovative amendments, and state-of-the-art evaluation of remediation effects are welcome to this Special Issue.

The following tops are acceptable in this Special Issue, including:

  • Fate and transport of contaminants in soil and water;
  • Innovative methodologies in design, characterization, modification, optimization of amendments;
  • Technologies combination, and the potential interactions;
  • Environmental responses towards amendment application;
  • Perspectives in establishing the whole process management and quality control system of soil and water remediation;
  • Data-driven research.

Prof. Dr. Jiangshan Li
Dr. Xiao Yang
Dr. Fei Wang
Guest Editors

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Keywords

  • soil pollution
  • water treatment
  • green and sustainable remediation
  • pollution control
  • risk assessment
  • multifunctional amendments
  • emerging contaminants

Published Papers (11 papers)

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Research

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16 pages, 20171 KiB  
Article
Spatial Distribution and Migration Mechanisms of Toxic Elements in Farmland Soil at Nonferrous Metal Smelting Site
by Buxing Shi, Kui Cai, Xiulan Yan, Zhaoshu Liu, Qian Zhang, Jun Du, Xiao Yang and Wenlou Luan
Water 2023, 15(12), 2211; https://doi.org/10.3390/w15122211 - 12 Jun 2023
Cited by 1 | Viewed by 1157
Abstract
Nonferrous metal smelting is a potential emission source of trace elements. However, it is vital to identify the dominant factors in determining toxic element (TE) spatial distribution and migration behaviors. We hypothesize that soil clay is the key factor in agricultural land around [...] Read more.
Nonferrous metal smelting is a potential emission source of trace elements. However, it is vital to identify the dominant factors in determining toxic element (TE) spatial distribution and migration behaviors. We hypothesize that soil clay is the key factor in agricultural land around nonferrous metal smelting areas. Hence, this study focused on Qingyuan Town, a typical nonferrous metal smelting base. From this site, 95 soil samples (0–20 cm) were collected from cultivated land around the nonferrous metal smelters. Eight soil samples were analyzed for TE speciation and clay minerals in hot spot and non-hot spot areas following the TE distribution. A geographical detector (Geodor) showed that the distributions of total and exchangeable TE were affected by multiple factors (clay, CaO, and Fe2O3). X-ray diffraction (XRD) showed that the clay was mainly comprised of an illite and smectite mixed layer (67.13%), illite (15.38%), chlorite (9.25%), and kaolinite (8.25%). Moreover, correlation analysis showed that the exchangeable As was positively correlated with illite (R2 = 0.76, at p < 0.01 level), kaolinite (R2 = 0.43, at p < 0.01 level), and chlorite (R2 = 0.59, at p < 0.01 level) in the hot spot, but negatively correlated with a mixed layer of illite and smectite (R2 = 0.83, at p < 0.01 level). In contrast, the cases of Cd, Cu, Pb, and Zn presented an opposite tread with As. The positive matrix factorization (PMF) results showed that the contribution rate of nonferrous metal smelting to soil As was 42.90% and those of Cd, Cu, Pb, and Zn were 84.90%, 56.40%, 59.90%, and 59.20%, respectively. These results can provide guidance for controlling the TE risk associated with agricultural land management. Full article
(This article belongs to the Special Issue Innovative Technologies for Soil and Water Remediation)
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15 pages, 1427 KiB  
Article
Effects of Chelating Agents Addition on Ryegrass Extraction of Cadmium and Lead in Artificially Contaminated Soil
by Wen Dong, Ruichen Wang, Huaien Li, Xiao Yang, Jiake Li, Hui Wang, Chunbo Jiang and Zhe Wang
Water 2023, 15(10), 1929; https://doi.org/10.3390/w15101929 - 19 May 2023
Cited by 2 | Viewed by 2211
Abstract
This study investigated the removal of cadmium (Cd) and lead (Pb) from the soil through phytoremediation using ryegrass combined with chelating agents. Soil leaching experiments were employed to determine the extraction efficiencies of chelating agents, including ethylenediaminetetraacetic acid (EDTA), citric acid (CA), sodium [...] Read more.
This study investigated the removal of cadmium (Cd) and lead (Pb) from the soil through phytoremediation using ryegrass combined with chelating agents. Soil leaching experiments were employed to determine the extraction efficiencies of chelating agents, including ethylenediaminetetraacetic acid (EDTA), citric acid (CA), sodium glutamate tetra acetate (GLDA), oxalic acid (OA), and diethylenetriaminepentaacetic acid (DTPA) on Cd and Pb. Soil pot experiments were conducted to determine the effects of five different chelating agents—GLDA, EDTA, DTPA, CA, and OA—on the growth of ryegrass and the enrichment of Cd and Pb. The main findings were as follows: (1) the extraction efficiencies for Cd and Pb in soil were found to be GLDA > EDTA > DTPA > CA > OA and EDTA > DTPA > GLDA > CA > OA, respectively. (2) The aminopolycarboxylic acid class of chelating agents significantly reduced Cd and Pb contents in the weak acid extractable and reducible states in the studied soil, yet were less effective in the extraction of their residue state. Using chelating agents increased the proportion of residual heavy metals while reducing those in the weak acid extractable and reducible states in the soil, thereby mitigating the harmful effects of these heavy metals on the soil ecology. Full article
(This article belongs to the Special Issue Innovative Technologies for Soil and Water Remediation)
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13 pages, 3601 KiB  
Article
Phosphorus Recovery and Simultaneous Heavy Metal Removal from ISSA in a Two-Compartment Cell
by Le Fang, Zuotai Zhang, Ying Mei, Linji Xu and Ze Ren
Water 2023, 15(2), 226; https://doi.org/10.3390/w15020226 - 4 Jan 2023
Cited by 1 | Viewed by 1937
Abstract
Traditional acid extraction or electrodialytic remediation (EDR) is inefficient to recover phosphorus (P) from incinerated sewage sludge ash (ISSA). This study used a hybrid process including acid extraction and EDR to extract P from ISSA and remove heavy metals/metals from the P extract [...] Read more.
Traditional acid extraction or electrodialytic remediation (EDR) is inefficient to recover phosphorus (P) from incinerated sewage sludge ash (ISSA). This study used a hybrid process including acid extraction and EDR to extract P from ISSA and remove heavy metals/metals from the P extract sequentially. Specifically, the P extract was obtained by extracting ISSA with 0.2 M H2SO4 and a two-compartment cell was applied in the following EDR process. Constant currents of 15 mA, 35 mA and 50 mA were applied for the electromigration of the heavy metals/metals. Results showed that the efficiency of heavy metals/metals removal fluctuated and was relatively low (approximately 20%) under a current of 15 mA. Increasing the current to 35 mA significantly increased the removal efficiency and that of 50 mA was conspicuous, except Fe, Al and As (<50%). Meanwhile, P gradually immigrated to the catholyte after an EDR duration of 96 h. Consistent with heavy metal/metal immigration results, the pH change and 50 mA voltage drop were dramatic (the pH change was 12 and the voltage drop was 11 V). In addition, flocculent precipitates, which were predominantly Ca, P, Al, Mg and Fe, were found in the catholyte. Full article
(This article belongs to the Special Issue Innovative Technologies for Soil and Water Remediation)
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11 pages, 2754 KiB  
Article
Mechanical Strength, Permeability, and Micromechanics of Municipal Sludge Modified with Calcium-Containing Industrial Solid Waste and Powdered Construction Waste
by Yajun Liu, Haijun Lu, Mengyi Liu, Yifan He, Hanxi Yu, Bin He and Yong Wan
Water 2023, 15(1), 91; https://doi.org/10.3390/w15010091 - 27 Dec 2022
Cited by 5 | Viewed by 1355
Abstract
Each year, China produces a substantial amount of municipal sludge, industrial waste (slag, fly ash, and desulfurized gypsum), and construction waste, while its recycling rate is low. If not disposed in a properly and timely manner, this inequity can have serious environmental impacts. [...] Read more.
Each year, China produces a substantial amount of municipal sludge, industrial waste (slag, fly ash, and desulfurized gypsum), and construction waste, while its recycling rate is low. If not disposed in a properly and timely manner, this inequity can have serious environmental impacts. This study aimed to prepare a new type of modified sludge material with high strength, low shrinkage, and low permeability by curing municipal sludge with industrial waste (slag, desulfurized gypsum, and fly ash) and powdered construction waste. At specific maintenance ages, the modified sludge material was examined for shrinkage deformation, water content, compressive strength, and hydraulic conductivity. The modified sludge material was also tested by scanning electron microscopy (SEM + EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) tests. The hydration products, micromorphology, and elemental composition of modified sludge were also analyzed at specific maintenance ages. These analyses revealed the mechanism of solidification of municipal sludge by industrial waste and powdered construction waste and the changes in the microstructure of the sludge. The results showed that the compressive strength of the modified sludge ranged from 3.83 to 8.63 MPa, volumetric shrinkage ranged from 2.12 to 12.68%, and hydraulic conductivity ranged from 1.65 × 10−8 to 2.21 × 10−7 cm/s after 28 d of maintenance. The active substances, such as SiO2, Al2O3, and CaO, in the industrial waste, powdered construction waste, and municipal sludge were subjected to a hydration reaction in an alkaline environment to produce dense blocks, agglomerates of C-S-H, ettringite, gismondine, and other hydration products. The compressive strength of the modified sludge increased, and its internal structure was dense. Full article
(This article belongs to the Special Issue Innovative Technologies for Soil and Water Remediation)
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15 pages, 2208 KiB  
Article
Long-Term Performance of Cement-Stabilized/Solidified Pb-Contaminated Soil under Simulated Erosive Environments
by Ping Wang, Xin Chen, Gang Zeng, Zhiwei Dong, Shiyu Liu, Xianwei Zhang and Ce Wang
Water 2022, 14(20), 3314; https://doi.org/10.3390/w14203314 - 20 Oct 2022
Cited by 5 | Viewed by 1437
Abstract
The performance of stabilization/solidification(S/S) monoliths is vital for the long-term effectiveness of potentially toxic-element-contaminated soil treatments, which arevulnerable to environmental conditions (e.g., strongly acidic or alkaline conditions). This study numerically investigated the long-term performance of S/S monolith materials in erosive environments with pHs [...] Read more.
The performance of stabilization/solidification(S/S) monoliths is vital for the long-term effectiveness of potentially toxic-element-contaminated soil treatments, which arevulnerable to environmental conditions (e.g., strongly acidic or alkaline conditions). This study numerically investigated the long-term performance of S/S monolith materials in erosive environments with pHs ranging from 2.65 to 10.00 over three years. It was found that the leachability and availability of Pb decreased continually over the three years due to the transformation of the chemical fractions of Pb from acid-soluble fractions to reducible and oxidizable fractions. Environmental pH greatly affected the strength and permeability of the S/S monoliths, which increased in weakly acidic and alkaline conditions (e.g., pH 5.00–10.00), while they were significantly reduced in strongly acidic conditions (e.g., pH 2.65–3.65). The strength of the S/S monolith decreased from 19.7 MPa to 0.2 Mpa after three years when the environmental pH was 2.65. A model was established to predict the long-term strength evolution of the S/S monolith. The dissolution of hydration products in the S/S monolith materials caused by acid erosion directly attenuated the strength and permeability of the S/S-treated soils. Long-term exposure to acidic environments could lead to the failure of S/S treatments. Thus, more attention should be paid to the long-term effectiveness of S/S monoliths in erosive environments. Full article
(This article belongs to the Special Issue Innovative Technologies for Soil and Water Remediation)
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14 pages, 4588 KiB  
Article
Preparation of Fe3O4/α-MnO2 Magnetic Nanocomposites for Degradation of 2,4-DCP through Persulfate Activation
by Yan Zhao, Fei Luo and Rui Zhou
Water 2022, 14(20), 3312; https://doi.org/10.3390/w14203312 - 20 Oct 2022
Cited by 3 | Viewed by 1822
Abstract
In this study, Fe3O4 magnetic nanoparticles (MNPs) were loaded on α-MnO2 nanowires using an improved hydrothermal synthesis method combined with an ultrasonic coprecipitation method, the loading ratio was optimized, the efficiency of the prepared Fe3O4/α-MnO [...] Read more.
In this study, Fe3O4 magnetic nanoparticles (MNPs) were loaded on α-MnO2 nanowires using an improved hydrothermal synthesis method combined with an ultrasonic coprecipitation method, the loading ratio was optimized, the efficiency of the prepared Fe3O4/α-MnO2-activated persulfate (PS) system for the degradation of 2,4-dichlorophenol (2,4-DCP) was investigated, and the effects of PS concentration, Fe3O4/α-MnO2 magnetic nanocomposites (MNCs) dosage, pH value and initial pollutant concentration on the degradation of 2,4-DCP were investigated. The results showed that when the initial concentrations of 2,4-DCP, PS, and Fe3O4/α-MnO2 MNCs were 100 mg/L, 30 mmol/L, and 0.4 g/L, the degradation rate of 2,4-DCP reached 96.3% after 180 min of reaction at 30 °C under a neutral condition, and the fitting results showed that the degradation of 2,4-DCP by the Fe3O4/α-MnO2-activated PS system conformed to quasi-first-order kinetics. The degradation of 2,4-DCP by different Fe3O4/α-MnO2-activated PS systems was compared, and a possible PS activation mechanism was proposed. The Fe3O4/α-MnO2 MNCs exhibited excellent reusability, and by introducing Fe3O4/α-MnO2 MNCs as the PS activator into the advanced oxidation process (AOP) system, the electron transfer of Mn(III/IV) and Fe(III/II) on the surface of MNCs was realized, thus greatly improving the reaction efficiency. Full article
(This article belongs to the Special Issue Innovative Technologies for Soil and Water Remediation)
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10 pages, 1046 KiB  
Article
Arsenic Concentration, Fraction, and Environmental Implication in Fe–Mn Nodules in the Karst Area of Guangxi
by Wenbing Ji, Rongrong Ying, Zhongfang Yang, Zhewei Hu, Qiong Yang, Xu Liu, Tao Yu, Lei Wang, Jianxun Qin and Tiansheng Wu
Water 2022, 14(19), 3021; https://doi.org/10.3390/w14193021 - 26 Sep 2022
Cited by 4 | Viewed by 1311
Abstract
We determined the concentrations, geochemical fractions, and potential environmental implications of arsenic (As) via pH-static extraction experiments, X-ray photoelectron spectroscopy (XPS), and sequential extraction. Compared with the corresponding soils, the enrichment factors followed the order As (4.27) > Fe (2.14) > P (1.71) [...] Read more.
We determined the concentrations, geochemical fractions, and potential environmental implications of arsenic (As) via pH-static extraction experiments, X-ray photoelectron spectroscopy (XPS), and sequential extraction. Compared with the corresponding soils, the enrichment factors followed the order As (4.27) > Fe (2.14) > P (1.71) > Mn (1.41) > Al (0.95) > Ti (0.44) > Si (0.39) > Mg (0.28) > K (0.13). As showed a higher enrichment factor than all other elements. Arsenic showed a high linear correlation with iron in the FMNs, which can be expressed as As = 18.68Fe − 175.89 (r2 = 0.97, p < 0.01), indicating that Fe plays an important role in the geochemical behavior of As. Most of the As occurred as As (V) (83.79%) in the Fe–Mn nodules (FMNs), and As (III) (16.21%) only occupied a small portion. The distribution of As in the geochemical fractions of the FMNs followed the order F5 (99.54%) > F3 (0.25%) > F4 (0.10%) > F2 (0.09%) > F1 (0.02%), indicating that the residual fraction (F5) of As is the most dominant component. The total release of As from the nodules was extremely low (<0.01%) under neutral pH conditions (pH 6.0–8.0), and As was adsorbed and stabilized by the FMNs under neutral pH conditions (pH 6.0–8.0). However, overacidification or alkalization of the soil environment will promote As release, with subsequent ecological hazards. Full article
(This article belongs to the Special Issue Innovative Technologies for Soil and Water Remediation)
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24 pages, 2343 KiB  
Article
Physical, Chemical, and Mineralogical Controls on Retardation of Anatoxin-a Migration by Sorption to Natural Soils with Implications for Groundwater Protection
by Justin L. Hobart, Andrew M. O’Reilly and Jennifer N. Gifford
Water 2022, 14(18), 2869; https://doi.org/10.3390/w14182869 - 14 Sep 2022
Cited by 3 | Viewed by 1701
Abstract
Increasing prevalence of cyanotoxins in surface water bodies worldwide threatens groundwater quality when contaminated water recharges an aquifer through natural or artificial means. The subsurface fate of anatoxin-a (ATX) is not well studied. Laboratory batch experiments were performed to expand the current knowledge [...] Read more.
Increasing prevalence of cyanotoxins in surface water bodies worldwide threatens groundwater quality when contaminated water recharges an aquifer through natural or artificial means. The subsurface fate of anatoxin-a (ATX) is not well studied. Laboratory batch experiments were performed to expand the current knowledge of ATX sorption affinities to geologic media, with a focus on natural soil (Vertisol, Ultisol, Alfisol, and Inceptisol) and physical, chemical, and mineralogical characteristics. For a range of aqueous ATX concentrations (0.3–14 μg/L), linear, Freundlich, and Langmuir isotherms fit observed data well (r2 = 0.92–1.00, RMSE = 0.4–6.3 μg/kg). Distribution coefficient (Kd) and retardation factor (Rf) values were computed for the linear isotherm, giving Kd of 22.3–77.1 L/kg and Rf of 62–256. Average percent removals were 85.0–92.2%. The strongest predictors of Kd were kaolinite and smectite group mineral abundances and for Rf were smectite group and silt and clay abundances. Results indicate that loamy, silty, or clayey soils—particularly Vertisols—tend to substantially slow migration of ATX through natural soil systems. Where implemented as a functionalized amendment in an engineered pollution control media, such soils may enhance natural ATX attenuation processes, thereby supporting the protection of in situ and extracted groundwater during irrigation, natural and managed aquifer recharge, or riverbank filtration. Full article
(This article belongs to the Special Issue Innovative Technologies for Soil and Water Remediation)
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16 pages, 7839 KiB  
Article
Analysis of the Remediation of Coal Tar-Contaminated Groundwater Using Ex Situ Remediation
by Marian Marschalko, Tomas Kempa, Dariusz Popielarczyk, Miroslav Cernik, Michaela Vicherkova, Petr Vicherek and Dominik Niemiec
Water 2022, 14(14), 2182; https://doi.org/10.3390/w14142182 - 10 Jul 2022
Cited by 2 | Viewed by 2573
Abstract
The article describes the remediation of contaminated groundwater during the ex situ remediation of coal tar contamination following the closure of a coking plant in the Moravian–Silesian Region (Czech Republic). The aim of the article is to point out the advantages of ex [...] Read more.
The article describes the remediation of contaminated groundwater during the ex situ remediation of coal tar contamination following the closure of a coking plant in the Moravian–Silesian Region (Czech Republic). The aim of the article is to point out the advantages of ex situ soil remediation via the excavation of the contaminated geological environment combined with thermal desorption, a method of removing contaminants both from soil and groundwater. Its advantage is the absolute qualitative and quantitative control over the contaminated soil with the possibility of precise segmentation into contaminated and non-contaminated soils. Next, all contaminated groundwater may be pumped off upon the construction of sealing walls to control groundwater flows. To excavate the soil, it is necessary to reduce the contaminated groundwater level inside the sealing walls and thus create conditions for the extraction of contaminated soils using standard machinery. In detail, the article describes the removal of the contaminated groundwater and compares the quality of the pumped and inflowing water before and after the remediation. The locality is characteristic of a high horizontal and vertical grain-size heterogeneity of gravel-sand, which led to a varying filtration coefficient affecting the capacities of pumped groundwater quantity during the remediation. At the start of the remediation process, the contaminant levels exceeded the limits by the Czech Environmental Inspectorate several times. The post-remediation monitoring showed that all the contaminant levels were below the limit. Surprisingly, the overall groundwater contamination amounted to 232.86 t of contaminants as non-aqueous phase liquids, and 6872.9 kg of dissolved contaminants. As much as 12,200 t of contaminants were removed from the soil. Full article
(This article belongs to the Special Issue Innovative Technologies for Soil and Water Remediation)
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15 pages, 6925 KiB  
Article
Effect of Consistency Limit on the Strength of Cement-Solidified Dredged Sludge: Modelling and Micro-Mechanism
by Shiquan Wang, Xingxing He, Jiangshan Li, Shenzhen Li, Huajin Qin, Yuanyuan Ma, Hongrui Ma, Shunmei Gong and Zhiyong Niu
Water 2022, 14(12), 1959; https://doi.org/10.3390/w14121959 - 18 Jun 2022
Cited by 4 | Viewed by 1859
Abstract
The unconfined compressive strength (UCS) of sludge with different consistency limits solidified by cement was investigated. The results showed that under the condition of constant initial water content, a higher liquid index of soil resulted in higher UCS. A novel strength-evaluation model based [...] Read more.
The unconfined compressive strength (UCS) of sludge with different consistency limits solidified by cement was investigated. The results showed that under the condition of constant initial water content, a higher liquid index of soil resulted in higher UCS. A novel strength-evaluation model based on the ratio of the liquid index to the cement content was developed, and the prediction deviation of the model was within 30%. The influence mechanism of the consistency limit of sludge on the cement solidification was revealed by scanning electron microscopy, mercury intrusion porosimetry, X-ray diffractometer and thermogravimetric analysis. For the cement-solidified dredged sludge (CDS) with a lower liquid index, a large amount of hydrate was interlaced with each other and wrapped soil particles, promoting the formation of a dense structure. For the CDS with a higher liquid index, hydrates such as C-S-H and ettringite challenged each other to play the role of “cementing particles” and “filling pores”, resulting in the formation of the porous structure. The mineralogical analyses confirmed that more C-S-H gels and ettringites were generated in the CDS with a lower liquid index, but less calcite was formed due to its denser structure. In engineering applications, reducing the liquid index by adjusting the consistency limit can improve the strength performance of CDS. Full article
(This article belongs to the Special Issue Innovative Technologies for Soil and Water Remediation)
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Review

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17 pages, 2644 KiB  
Review
Application Progress of New Adsorption Materials for Removing Fluorine from Water
by Ming−Ming Zhao, Qiang Wang, Luke Saye Nenwon Krua, Rong−Nan Yi, Run−Jun Zou, Xin−Yuan Li and Peng Huang
Water 2023, 15(4), 646; https://doi.org/10.3390/w15040646 - 7 Feb 2023
Cited by 4 | Viewed by 3381
Abstract
A large amount of fluorine−containing wastewater was produced with the rapid development of the industry. Excessive fluoride content in water will not only endanger ecological security but also pose threat to human health. In this study, common new adsorbents for defluorination, such as [...] Read more.
A large amount of fluorine−containing wastewater was produced with the rapid development of the industry. Excessive fluoride content in water will not only endanger ecological security but also pose threat to human health. In this study, common new adsorbents for defluorination, such as metal−based adsorbents, natural adsorbents, and nanomaterial adsorbents were reviewed for its physicochemical properties and fluorine removal efficiency. The fluorine removal mechanism of different adsorbents was introduced in detail, and the future work of the removal of fluorine using novel adsorbents was proposed. This research also introduces the application of the coupling of the adsorption method with the technology of chemical precipitation, filtration, and super−magnetic separation to treat high concentration of fluoride wastewater. A good selection of process combinations according to different needs can achieve high−efficiency defluorination in water. Finally, some existing problems of practical operation of fluorine using removal materials in the environment are summarized, hoping to contribute to the future research of fluorine removal materials. Full article
(This article belongs to the Special Issue Innovative Technologies for Soil and Water Remediation)
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