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Song C, Sun S, Wang J, Gao Y, Yu G, Li Y, Liu Z, Zhang W, Zhou L. Applying fulvic acid for sediment metals remediation: Mechanism, factors, and prospect. Front Microbiol 2023; 13:1084097. [PMID: 36699598 PMCID: PMC9868176 DOI: 10.3389/fmicb.2022.1084097] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 12/19/2022] [Indexed: 01/11/2023] Open
Abstract
Fulvic acid (FA) has been shown to play a decisive role in controlling the environmental geochemical behavior of metals. As a green and natural microbial metabolite, FA is widely used in environmental remediation because of its good adsorption complexation and redox ability. This paper introduces the reaction mechanism and properties of FA with metals, and reviews the progress of research on the remediation of metal pollutant by FA through physicochemical remediation and bioremediation. FA can control the biotoxicity and migration ability of some metals, such as Pb, Cr, Hg, Cd, and As, through adsorption complexation and redox reactions. The concentration, molecular weight, and source are the main factors that determine the remediation ability of FA. In addition, the ambient pH, temperature, metal ion concentrations, and competing components in sediment environments have significant effects on the extent and rate of a reaction between metals and FA during the remediation process. Finally, we summarize the challenges that this promising environmental remediation tool may face. The research directions of FA in the field of metals ecological remediation are also prospected. This review can provide new ideas and directions for the research of remediation of metals contaminants in sediments.
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Affiliation(s)
- Chuxuan Song
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha, China
| | - Shiquan Sun
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha, China.,Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha, China
| | - Jinting Wang
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha, China
| | - Yang Gao
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha, China
| | - Guanlong Yu
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha, China
| | - Yifu Li
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha, China
| | - Zhengqian Liu
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Wei Zhang
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha, China
| | - Lean Zhou
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha, China
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Study on the Behaviors and Mechanism of Ni(II) Adsorption at the Hydroxyapatite-Water Interface: Effect of Particle Size. ADSORPT SCI TECHNOL 2022. [DOI: 10.1155/2022/3838766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Hydroxyapatite (HAP) was a highly efficient decontamination material for its strong adsorption capacity used in the immobilization of heavy metals, while the particle-size effect was insufficiently investigated during the sorption process. In the present study, the mechanisms of nickel (Ni(II)) adsorption on HAPs with two different particle sizes were investigated by combing batch experiments, desorption, and XRD analysis. The results showed that the adsorption capacity of 20 nm HAP (nano-HAP) was much higher than that of 12 μm HAP (micro-HAP). It was noticed that the results of the present study also clarified the distinct mechanisms in each adsorption process. As for micro-HAP, Ni2+ adsorbed through slow diffusion and replacement with Ca2+ and then incorporated in the lattice at pH between 6.5 and 9.0, which was confirmed by the results of kinetics, thermodynamics, and desorption. And a more compact crystalline structure and irreversible desorption behavior of micro-HAP after Ni(II) adsorption was confirmed by results of XRD and desorption isotherms, respectively. At
, lattice incorporation and precipitation controlled together. However, for nano-HAP, the sharp increase of Ni(II) adsorption and ionic strength dependent at pH 6.5 to 9.0 revealed that the dominant mechanisms were ionic exchange and inner-sphere complexation. XRD results showed that characteristic peaks of cassidyite appeared in Ni(II)-loading nano-HAP. At
, a precipitate of Ni(II) was the dominant mechanism. The experimental finds demonstrated that nanoscale HAP was a more fast, efficient, and desorbable adsorbent than micro-HAP for Ni(II) removal. These findings would be favorable for investigating the removal mechanisms of heavy metals on the HAP materials and designing the synthesis methods.
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Wu M, Bi E, Li B. Cotransport of nano-hydroxyapatite and different Cd(II) forms influenced by fulvic acid and montmorillonite colloids. WATER RESEARCH 2022; 218:118511. [PMID: 35512536 DOI: 10.1016/j.watres.2022.118511] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 04/09/2022] [Accepted: 04/23/2022] [Indexed: 06/14/2023]
Abstract
Soil colloids can affect the cotransport of nanoparticles and pollutants. In this study, the influencing mechanisms of organic fulvic acid (FA) and inorganic montmorillonite colloid (MONT) on the cotransport of nHAP and Cd(II) were investigated. Column experiments combined with Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, attachment efficiency calculation and two-site kinetic retention model were applied to study the mechanisms. Results showed that the co-existence of FA or MONT made the transport of nHAP improved by 58-75% and 33-59%, respectively. Both of them could improve the stability of nHAP particles and enhance electrostatic repulsion between nHAP particles and sand. Retention of nHAP in the sand was mainly caused by secondary energy minimum and physical straining. The co-existence of FA or MONT changed the amount of adsorbed species of Cd(II) and decreased the retardation effect of nHAP on Cd(II) transport. With increasing FA concentration, soluble FA·Cd and suspended nHAP·FA·Cd complexes in the system increased. Transport of soluble Cd(II) and total Cd(II) were strengthened due to the concentration effect of FA and the improved stability of nHAP particles. With increasing MONT concentration, the amount of soluble Cd(II) decreased, but that of colloidal Cd(II) (nHAP·Cd and MONT·Cd) increased. Due to the stronger effect of colloidal Cd(II) change than that of the soluble Cd(II) change, the transport of total Cd(II) was improved by 34-57%. The findings of this study can help to understand the fate of nanoparticles and Cd(II) in natural water and soil.
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Affiliation(s)
- Mengmeng Wu
- School of Water Resources and Environment, Beijing Key Laboratory of Water Resources and Environmental Engineering, and MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing 100083, PR China; China National Environmental Monitoring Centre, Beijing 100012, PR China
| | - Erping Bi
- School of Water Resources and Environment, Beijing Key Laboratory of Water Resources and Environmental Engineering, and MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing 100083, PR China.
| | - Binghua Li
- Department of Water Resources, Beijing Water Science and Technology Institute, Beijing 100048, PR China
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Zhou C, Song X, Wang Y, Wang H, Ge S. The sorption and short-term immobilization of lead and cadmium by nano-hydroxyapatite/biochar in aqueous solution and soil. CHEMOSPHERE 2022; 286:131810. [PMID: 34399259 DOI: 10.1016/j.chemosphere.2021.131810] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/26/2021] [Accepted: 08/04/2021] [Indexed: 06/13/2023]
Abstract
In this study, the composite materials using different ratios of biochar (BC) to nano-hydroxyapatite (nHAP) were prepared for the remediation of lead (Pb) and cadmium (Cd) contaminated water and soil. The sorption and the immobilization experiments indicated a higher sorption capacity and immobilization efficiency of Pb compared to those of Cd. The characteristics of XRD, FTIR, SEM, and XPS manifested that dissolution-precipitation, cation exchange, complexation, and cation-π interaction were the main four mechanisms for the sorption of Pb2+ and Cd2+ using composite material PC1 (nHAP/BC = 1/1). From semi-quantitative analysis, the mineral effect accounted for the majority of the immobilization of Pb and Cd. Due to obvious Pb-precipitates in the sorbed material, dissolution-precipitation primarily affected the sorption of Pb using PC1, while the immobilization of Cd was mainly attributable to cation exchange. Such results corresponded to the stable Pb-precipitates and unstable Cd-compounds in soil, among which the latter was prone to be released into the environment. The sorption capacity in aqueous solutions and the immobilization efficiencies in the soil for both Pb and Cd increased with the addition of nHAP, which were linearly correlated to the nHAP proportion in the composite materials. In future practical applications, the percentages of composite materials can be designed according to the specific pollutant concentration. This study sheds light on the explicit immobilization mechanisms for Pb and Cd in aqueous solutions to better understand their behaviors in the soil remediated by relevant materials.
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Affiliation(s)
- Cailing Zhou
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China
| | - Xin Song
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China
| | - Yiwei Wang
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China
| | - Hui Wang
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China
| | - Shifu Ge
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, China.
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Yao Y, Li J, He C, Hu X, Yin L, Zhang Y, Zhang J, Huang H, Yang S, He H, Zhu F, Li S. Distribution Characteristics and Relevance of Heavy Metals in Soils and Colloids Around a Mining Area in Nanjing, China. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2021; 107:996-1003. [PMID: 34374788 DOI: 10.1007/s00128-021-03350-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 07/24/2021] [Indexed: 06/13/2023]
Abstract
Heavy metal pollution in agricultural soils poses a direct threat to food safety and human health. It has been shown that the colloids is the carrier of heavy metal transport in the polluted soil by heavy metals, but the sources of heavy metals in the soil and colloids and their interrelations are not transparent at present. This study aims to investigate the distribution characteristics of heavy metals in agricultural soils near mining areas, and reveal the relevance of heavy metal content in colloids with total content in soils and their chemical species in soils. Results showed that the concentrations of Mn, Zn, and Pb in agricultural soils and colloids were higher than those of other heavy metals. The content of heavy metals in colloids was positively correlated with the total content of heavy metals in soil. Heavy metals in soil could be easily combined by humus-like substances and tryptophan-like protein in the colloids. The primary source of heavy metals in soil and colloids was mining activities. This study provides theoretical support for revealing the pollution characteristics and migration of heavy metals in agricultural soils and colloids around mining areas.
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Affiliation(s)
- Youru Yao
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Jing Li
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Cheng He
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200082, China
| | - Xin Hu
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Li Yin
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Yong Zhang
- Department of Geological Sciences, University of Alabama, Tuscaloosa, AL, 35487, USA
| | - Jie Zhang
- Analytical and Testing Center, Nanjing Normal University, Nanjing, 210023, China
| | - Heyong Huang
- Analytical and Testing Center, Nanjing Normal University, Nanjing, 210023, China
| | - Shaogui Yang
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Huan He
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Fengxiao Zhu
- School of Environment, Nanjing Normal University, Nanjing, 210023, China.
| | - Shiyin Li
- School of Environment, Nanjing Normal University, Nanjing, 210023, China.
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Wei W, Han X, Shao Y, Xie W, Zhang Y, Yao Y, Zhao W, Han R, Li S, Zhang Y, Zheng C. Comparing the effects of humic acid and oxalic acid on Pb(II) immobilization by a green synthesized nanocrystalline hydroxyapatite. CHEMOSPHERE 2021; 285:131411. [PMID: 34246936 DOI: 10.1016/j.chemosphere.2021.131411] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 06/20/2021] [Accepted: 06/26/2021] [Indexed: 06/13/2023]
Abstract
Dissolved organic matter (DOM) is one of the most significant parameters to affect the remediation efficiency of Pb(II) by apatites. Numerous studies chose humic substances as a surrogate of DOM to investigate its influence on Pb(II) immobilization. However, the effect of low-molecular-weight organic acids such as oxalic acid (OA), which is ubiquitous in the environment and a primary component of DOM, in immobilizing Pb(II) was still not fully understood. Herein, humic acid (HA) and OA were examined to distinguish their influence on Pb(II) immobilization by a green synthesized nanocrystalline hydroxyapatite (nHAP). Various parameters were considered to evaluate the removal performance of nHAP towards Pb(II) as affected by HA/OA. Results indicated that Pb(II) immobilization was significantly promoted in the coexistence of OA owing to the precipitation of hydroxypyromorphite (HPY) as well as PbC2O4, but was independent on the addition sequence and slightly hindered by HA, disclosing that Pb(II) preferred to bind directly with nHAP instead of via HA. Characterization of the Pb(II) loaded solids by multiple technologies revealed that HPY was the predominant precipitate both in the absence and presence of HA, while the formation of PbC2O4 was preferred over that of HPY in the existence of OA. X-ray photoelectron spectroscopy indicated that PbC2O4 was the prevalent solid phase with the ratio of 62.97% after Pb(II) immobilization by nHAP in the presence of OA. These findings implied that the transformation efficiency of Pb(II) to HPY by apatites can be overestimated in the presence of OA due to the precipitation of PbC2O4.
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Affiliation(s)
- Wei Wei
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, 210023, China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Shenzhen, 518055, China.
| | - Xuan Han
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Yi Shao
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Wenming Xie
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Yong Zhang
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Yijun Yao
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wei Zhao
- School of Materials Engineering, Changshu Institute of Technology, Changshu, 215500, China
| | - Ruiming Han
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Shiyin Li
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Yong Zhang
- Department of Geological Sciences, University of Alabama, Tuscaloosa, AL, 35487, USA.
| | - Chunmiao Zheng
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Shenzhen, 518055, China; State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China.
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Brazdis RI, Fierascu I, Avramescu SM, Fierascu RC. Recent Progress in the Application of Hydroxyapatite for the Adsorption of Heavy Metals from Water Matrices. MATERIALS (BASEL, SWITZERLAND) 2021; 14:6898. [PMID: 34832297 PMCID: PMC8618790 DOI: 10.3390/ma14226898] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/11/2021] [Accepted: 11/12/2021] [Indexed: 12/27/2022]
Abstract
Wastewater treatment remains a critical issue globally, despite various technological advancements and breakthroughs. The study of different materials and technologies gained new valences in the last years, in order to obtain cheap and efficient processes, to obtain a cleaner environment for future generations. In this context, the present review paper presents the new achievements in the materials domain with highlights on apatitic materials used for decontamination of water loaded with heavy metals. The main goal of this review is to present the adsorptive removal of heavy metals using hydroxyapatite-based adsorbents, offering a general overview regarding the recent progress in this particular area. Developing the current review, an attempt has been made to give appropriate recognition to the most recent data regarding the synthesis methods and targeted pollutants, including important information regarding the synthesis methods and precursors, morphological characteristics of the adsorbent materials and effectiveness of processes.
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Affiliation(s)
- Roxana Ioana Brazdis
- National Institute for Research & Development in Chemistry and Petrochemistry—ICECHIM, 060021 Bucharest, Romania;
- Department of Science and Engineering of Oxide Materials and Nanomaterials, University “Politehnica” of Bucharest, 011061 Bucharest, Romania
| | - Irina Fierascu
- National Institute for Research & Development in Chemistry and Petrochemistry—ICECHIM, 060021 Bucharest, Romania;
- Faculty of Horticulture, University of Agronomic Sciences and Veterinary Medicine of Bucharest, 011464 Bucharest, Romania
| | - Sorin Marius Avramescu
- Research Center for Environmental Protection and Waste Management, University of Bucharest, 91-95 Splaiul Independentei, 050095 Bucharest, Romania;
- Department of Organic Chemistry, Biochemistry and Catalysis, Faculty of Chemistry, University of Bucharest, 90-92 Soseaua Panduri, 050663 Bucharest, Romania
| | - Radu Claudiu Fierascu
- National Institute for Research & Development in Chemistry and Petrochemistry—ICECHIM, 060021 Bucharest, Romania;
- Department of Science and Engineering of Oxide Materials and Nanomaterials, University “Politehnica” of Bucharest, 011061 Bucharest, Romania
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Wei W, Li J, Han X, Yao Y, Zhao W, Han R, Li S, Zhang Y, Zheng C. Insights into the adsorption mechanism of tannic acid by a green synthesized nano-hydroxyapatite and its effect on aqueous Cu(II) removal. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 778:146189. [PMID: 33714103 DOI: 10.1016/j.scitotenv.2021.146189] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 01/31/2021] [Accepted: 02/24/2021] [Indexed: 06/12/2023]
Abstract
The polyphenolic tannic acid (TA) has been widely used in the stabilization and surface modification of nanomaterials. The interaction mechanism of TA with the biogenic nano-hydroxyapatite (nHAP) and its environmental importance, however, are poorly understood. This study explored the adsorption of TA using the green synthesized, eggshell-derived nHAP and implications of this process for the removal of aqueous Cu(II) via batch adsorption experiments, Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) investigations. TA adsorption by nHAP was a complex pH-dependent process and significantly correlated with TA molecule speciation and amphoteric properties of nHAP via multiple adsorption modes including surface complexation, electrostatic attraction, and hydrogen bond. The maximum TA adsorption amount was found to be 94.8 mg/g for less crystalline nHAP with lower calcination temperature. In the ternary Cu-TA-nHAP systems, TA promoted Cu(II) adsorption at pH < 5 and reduced Cu(II) uptake at pH > 5. Further studies of the effects of ionic strength and addition sequences, as well as Raman, FTIR, and XPS analyses revealed Cu(II) adsorption on nHAP was mainly dominated by inner-sphere surface complexation. These results can shed light on not only the utility of biogenic nHAP for TA and Cu(II) adsorption but also the evaluation of the effect of TA on the environmental behavior of heavy metals.
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Affiliation(s)
- Wei Wei
- School of Environment, Nanjing Normal University, Nanjing 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Shenzhen 518055, China
| | - Junsuo Li
- School of Environment, Nanjing Normal University, Nanjing 210023, China
| | - Xuan Han
- School of Environment, Nanjing Normal University, Nanjing 210023, China
| | - Yijun Yao
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Zhao
- School of Chemistry and Chemical Engineering, Huaiyin Normal University, Huaian, China
| | - Ruiming Han
- School of Environment, Nanjing Normal University, Nanjing 210023, China
| | - Shiyin Li
- School of Environment, Nanjing Normal University, Nanjing 210023, China
| | - Yong Zhang
- Department of Geological Sciences, University of Alabama, Tuscaloosa, AL 35487, USA.
| | - Chunmiao Zheng
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Shenzhen 518055, China; State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science & Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.
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Zhou D, Han X, Zhang Y, Wei W, Green CT, Sun H, Zheng C. Co-transport of biogenic nano-hydroxyapatite and Pb(II) in saturated sand columns: Controlling factors and stochastic modeling. CHEMOSPHERE 2021; 275:130078. [PMID: 33984912 DOI: 10.1016/j.chemosphere.2021.130078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 01/29/2021] [Accepted: 02/21/2021] [Indexed: 06/12/2023]
Abstract
Biogenic nano-hydroxyapatite (bio-nHAP) has recently gained great interest in many domains, especially in the remediation of heavy metal-contaminated soil, due to its high reactivity, low cost, and eco-friendly nature. The co-transport and reaction of bio-nHAP with Pb(II) in saturated porous media, however, are not well understood. This work investigated the effects of ionic strength (IS), ionic composition (IC), dissolved organic matter (DOM), and flow velocity on transport-reaction dynamics of Pb(II) and bio-nHAP by combining column breakthrough experiments and model simulations. Results showed that the mobility of Pb(II) was significantly enhanced with increasing IS/IC but less affected by flow velocity during the transport-reaction process of bio-nHAP and Pb(II) in the saturated sand column; while the transport of bio-nHAP was restricted by increasing IS/IC but facilitated by increasing velocity. IC, IS, and velocity only slightly affected the reaction kinetics between Pb(II) and bio-nHAP, likely due to the fast reaction rate between Pb(II) and bio-nHAP and precipitation of pyromorphite. The transport dynamics of bio-nHAP and Pb(II) were significantly changed by DOM, and this effect depended strongly on the type of DOM with different molecular weights. Breakthrough curves of Pb(II) and bio-nHAP exhibited apparent "anomalous", sub-diffusive transport behaviors, which could be well quantified by a novel tempered fractional derivative bimolecular reaction equation (T-FBRE). Our findings highlighted the accurate simulation of the co-transport and reaction of bio-nHAP with Pb(II) using T-FBRE and had a great benefit for risk assessment and remediation strategy development for Pb(II) contaminated soil.
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Affiliation(s)
- Dongbao Zhou
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, College of Mechanics and Materials, Hohai University, Nanjing, 210098, China
| | - Xuan Han
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Yong Zhang
- Department of Geological Sciences, University of Alabama, Tuscaloosa, AL, 35487, USA.
| | - Wei Wei
- School of Environment, Nanjing Normal University, Nanjing, 210023, China.
| | | | - HongGuang Sun
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, College of Mechanics and Materials, Hohai University, Nanjing, 210098, China
| | - Chunmiao Zheng
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science & Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
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