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Ren P, Wang L, Ma T, Zhao Y, Guo B, Luo C, Li S, Ji P. A thorough investigation into the adsorption behavior of sophorolipid-modified fly ash towards compound pollution of lead and tetracycline. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 947:174679. [PMID: 38992370 DOI: 10.1016/j.scitotenv.2024.174679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Revised: 07/05/2024] [Accepted: 07/08/2024] [Indexed: 07/13/2024]
Abstract
Heavy metal ions and antibiotics were simultaneously detected in authentic water systems. This research, for the first time, employed synthesized sophorolipid-modified fly ash(SFA) to eliminate tetracycline(TC) and lead(Pb2+) from wastewater. Various characterization techniques, including SEM-EDS, FTIR, XPS, BET, and Zeta, were employed to investigate the properties of the SFA. The results showed that the sophorolipid modification significantly improved the fly ash's adsorption capacities for the target pollutants. The static adsorption experiments elucidated the adsorption behaviors of SFA towards TC and Pb2+ in single and binary systems, highlighting the effects of different Environmental factors on the adsorption behavior in both types of systems. In single systems, SFA exhibited a maximum adsorption capacity of 128.96 mg/g for Pb2+ and 55.57 mg/g for TC. The adsorption of Pb2+ and TC followed pseudo-second-order kinetics and Freundlich isotherm models. The adsorption reactions are endothermic and occur spontaneously. SFA demonstrates varying adsorption mechanisms for two different types of pollutants. In the case of Pb2+, the primary mechanisms include ion exchange, electrostatic interaction, cation-π interaction, and complexation, while TC primarily engages in hydrogen bonding, π-π interaction, and complexation. The interaction between Pb2+ and TC has been shown to improve adsorption efficiency at low concentrations. Additionally, adsorption-desorption experiments confirm the reliable cycling performance of modified fly ash, highlighting its potential as a cost-effective and efficient adsorbent for antibiotics and heavy metals.
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Affiliation(s)
- Pengyu Ren
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
| | - Lu Wang
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
| | - Tianhai Ma
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
| | - Yimo Zhao
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
| | - Bin Guo
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
| | - Chi Luo
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China
| | - Shaohua Li
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China.
| | - Puhui Ji
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China.
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Singh R, Naik DV, Dutta RK, Kanaujia PK. High surface area biochar for the removal of naphthenic acids from environmental water and industrial wastewater. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024:10.1007/s11356-024-34127-7. [PMID: 38963622 DOI: 10.1007/s11356-024-34127-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 06/21/2024] [Indexed: 07/05/2024]
Abstract
This study reports the production of biochar adsorbents from two major crop residues (i.e., rice and wheat straw) to remove naphthenic acids from water. The alkali treatment approach was used for biochar activation that resulted in a tremendous increase in their surface area, i.e., up to 2252 and 2314 m2/g, respectively, for rice and wheat straw biochars. Benzoic acid was used as a model compound to optimize critical adsorption parameters. Its maximum monolayer adsorption capacity of 459.55 and 357.64 mg/g was achieved for activated rice and wheat straw biochars. The adsorption of benzoic acid was exothermic (∆H° = - 7.06 and - 3.89 kJ/mol) and identified possibly as physisorption (Gibbs free energy ranges 3.5-4.0 kJ/mol). The kinetic study suggested that adsorption follows pseudo-second-order kinetics with qe2 for rice straw and wheat straw-derived adsorbents at 200 and 194 mg/g, respectively. As adsorbent, the recyclability of activated biochars was noticed with no significant loss in their efficiency for up to ten successive regeneration cycles. The adsorption results were validated using a commercial naphthenic acid mixture-spiked river water and paper/pulp industrial effluent. The activated rice and wheat straw biochars exhibited excellent adsorption efficiency of 130.3 and 74.6 mg/g, respectively. The naphthenic acid adsorption on biochar surface was due to various interactions, i.e., weak van der Waal's, pore filling, π-π stacking, and ionic interactions. This study offers a cost-effective and eco-friendly approach to valorizing agricultural residues for pollutant removal from industrial wastewater, including petroleum refineries.
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Affiliation(s)
- Raghuvir Singh
- Analytical Sciences Division, Indian Institute of Petroleum, Council of Scientific and Industrial Research, Haridwar Road, Dehradun, 248005, Uttarakhand, India
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, 247667, Uttarakhand, India
| | - Desavath V Naik
- Distillate and Heavy Oil Processing Division, Indian Institute of Petroleum, Council of Scientific and Industrial Research, Haridwar Road, Dehradun, 248005, Uttarakhand, India
| | - Raj K Dutta
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, 247667, Uttarakhand, India
| | - Pankaj K Kanaujia
- Analytical Sciences Division, Indian Institute of Petroleum, Council of Scientific and Industrial Research, Haridwar Road, Dehradun, 248005, Uttarakhand, India.
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Radoor S, Kandel DR, Chang S, Karayil J, Lee J. Carrageenan/calcium alginate composite hydrogel filtration membranes for efficient cationic dye separation. Int J Biol Macromol 2024; 270:132309. [PMID: 38740157 DOI: 10.1016/j.ijbiomac.2024.132309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 05/06/2024] [Accepted: 05/10/2024] [Indexed: 05/16/2024]
Abstract
The development of biopolymer-based filtration systems for water remediation applications is an extremely fascinating area of research. In this paper, we developed a biopolymer-based filtration system using sodium alginate (NaAlg) and carrageenan (Car) for the removal of the toxic cationic dye, methylene blue (MB). The membrane's properties were assessed using FTIR, TGA, UTM, FESEM, EDS, XRD, and water uptake, revealing commendable thermomechanical stability (5.79 MPa), good hydrophilicity, and compatibility. The experimental results further revealed that lambda Car/calcium alginate (λ-Car/CaAlg) exhibited superior dye rejection (100%) and flux (11.67 L m-2 h-1) compared to kappa Car/CaAlg (κ-Car/CaAlg) (99.22% and 11.19 L m-2 h-1) and plain alginate (CaAlg) (99.63% and 9.79 L m-2 h-1). The high MB rejection rate was attributed to the sieving mechanism and electrostatic interaction. A rejection rate of 100% was achieved at an initial MB concentration of 10 mg/L, pressure of 0.1 MPa, pH of 7, and temperature of 25°C. Furthermore, the hydrogel membranes demonstrated excellent recyclability over nine cycles, indicating their potential for water treatment applications.
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Affiliation(s)
- Sabarish Radoor
- Department of Polymer-Nano Science and Technology, Jeonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 54896, Republic of Korea
| | - Dharma Raj Kandel
- Department of Bionanotechnology and Bioconvergence Engineering, Jeonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 54896, Republic of Korea
| | - Seungwon Chang
- Department of Bionanotechnology and Bioconvergence Engineering, Jeonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 54896, Republic of Korea
| | - Jasila Karayil
- Department of Applied Science, Government Engineering College West Hill, Kozhikode, Kerala, India
| | - Jaewoo Lee
- Department of Polymer-Nano Science and Technology, Jeonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 54896, Republic of Korea; Department of Bionanotechnology and Bioconvergence Engineering, Jeonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 54896, Republic of Korea; Department of JBNU-KIST Industry-Academia Convergence Research, Polymer Materials Fusion Research Center, Jeonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 54896, Republic of Korea.
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Abdel Azim E, Samy M, Hanafy M, Mahanna H. Novel mint-stalks derived biochar for the adsorption of methylene blue dye: Effect of operating parameters, adsorption mechanism, kinetics, isotherms, and thermodynamics. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 357:120738. [PMID: 38574710 DOI: 10.1016/j.jenvman.2024.120738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Revised: 03/17/2024] [Accepted: 03/19/2024] [Indexed: 04/06/2024]
Abstract
The pyrolysis of mint stalks and lemon peels was performed to synthesize mint-stalks (MBC) and lemon-peels (LBC) derived biochars for adsorbing methylene blue (MB). The preparation, characterization, and application of MBC in adsorption have not been reported in the literature. MBC showed higher surface area and carbon content than that of LBC. The removal ratios of MB were 87.5% and 60% within 90 min for MBC and LBC, respectively at pH 7, temperature of 30oC, adsorbent dose of 0.5 g/L, and MB concentration of 5 mg/L. The optimal MBC dose was 1 g/L achieving a removal efficiency of 93.6% at pH 7, temperature of 30oC, contact time of 90 min, and initial dye concentration of 5.0 mg/L. The adsorption efficiency decreased from 98.6% to 31.33% by raising the dye concentration from 3.0 mg/L to 30 mg/L. Further, the increase of adsorbent dose to 10 g/L could achieve 94.2%, 90.3%, 87.6%, and 84.1% removal efficiencies of MB in the case of initial concentrations of 200 mg/L, 300 mg/L, 400 mg/L, and 500 mg/L, respectively. MBC showed high stability in adsorbing MB under five cycles, and the performed analyses after adsorption reaffirmed the stability of MBC. The adsorption mechanism indicated that the adsorption of MB molecules on the biochar's surface was mainly because of the electrostatic interaction, hydrogen bonding, and π-π stacking. Pseudo-second-order and Langmuir models could efficiently describe the adsorption of MB on the prepared biochar. The adsorption process is endothermic and spontaneous based on the adsorption thermodynamics. The proposed adsorption system is promising and can be implemented on a bigger scale. Moreover, the prepared biochar can be implemented in other applications such as photocatalysis, periodate, and persulfate activation-based advanced oxidation processes.
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Affiliation(s)
- Eman Abdel Azim
- Environmental Engineering, Management and Technology, Faculty of Engineering, Mansoura University, Mansoura, 35516, Egypt.
| | - Mahmoud Samy
- Public Works Engineering Department, Faculty of Engineering, Mansoura University, Mansoura, 35516, Egypt.
| | - Mahmoud Hanafy
- Engineering Mathematics and Physics Department, Faculty of Engineering, Mansoura University, Mansoura, 35516, Egypt.
| | - Hani Mahanna
- Public Works Engineering Department, Faculty of Engineering, Mansoura University, Mansoura, 35516, Egypt.
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Liu X, Tang Y, Wang X, Sarwar MT, Zhao X, Liao J, Zhang J, Yang H. Efficient Adsorbent Derived from Phytolith-Rich Ore for Removal of Tetracycline in Wastewater. ACS OMEGA 2024; 9:8287-8296. [PMID: 38405464 PMCID: PMC10883018 DOI: 10.1021/acsomega.3c09049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/25/2024] [Accepted: 01/26/2024] [Indexed: 02/27/2024]
Abstract
In recent decades, the tetracycline (TC) concentration in aquatic ecosystems has gradually increased, leading to water pollution problems. Various mineral adsorbents for the removal of tetracyclines have garnered considerable attention. However, efficient adsorbents suitable for use in a wide pH range environment have rarely been reported. Herein, a phytolith-rich adsorbent (PRADS) was prepared by a simple one-step alkali-activated pyrolysis treatment using phytolith as a raw material for effectively removing TC. PRADS, benefiting from its porous structure, which consists of acid- and alkali-resistant, fast-adsorbing macroporous silica and mesoporous carbon, is highly desirable for efficient TC removal from wastewater. The results indicate that PRADS exhibited excellent adsorption performance and stability for TC over a wide pH range of 2.0-12.0 under the coexistence of competing ions, which could be attributed to the fact that PRADS has a porous structure and contains abundant oxygen-containing functional groups and a large number of bonding sites. The adsorption mechanisms of PRADS for TC were mainly attributed to pore filling, hydrogen bonding, π-π electron-donor-acceptor, and electrostatic interactions. This work could offer a novel preparation strategy for the effective adsorption of pollutants by new functionalized phytolith adsorbents.
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Affiliation(s)
- Xi Liu
- Hunan
Key Laboratory of Mineral Materials and Application, School of Minerals
Processing and Bioengineering, Central South
University, Changsha 410083, China
- Department
of Natural Resources of Jiangxi Province, Jiangxi Province Natural Resources Interests and Reserve Security
Center, Nanchang 330025, China
| | - Yili Tang
- Hunan
Key Laboratory of Mineral Materials and Application, School of Minerals
Processing and Bioengineering, Central South
University, Changsha 410083, China
| | - Xianguang Wang
- Department
of Natural Resources of Jiangxi Province, Jiangxi Mineral Resources Guarantee Service Center, Nanchang 330025, China
| | - Muhammad Tariq Sarwar
- Engineering
Research Center of Nano-Geomaterials of Ministry of Education, China University of Geosciences, Wuhan 430074, China
- Laboratory
of Advanced Mineral Materials, China University
of Geosciences, Wuhan 430074, China
- Faculty of
Materials Science and Chemistry, China University
of Geosciences, Wuhan 430074, China
| | - Xiaoguang Zhao
- Hunan
Key Laboratory of Mineral Materials and Application, School of Minerals
Processing and Bioengineering, Central South
University, Changsha 410083, China
| | - Juan Liao
- Hunan
Key Laboratory of Mineral Materials and Application, School of Minerals
Processing and Bioengineering, Central South
University, Changsha 410083, China
| | - Jun Zhang
- Hunan
Key Laboratory of Mineral Materials and Application, School of Minerals
Processing and Bioengineering, Central South
University, Changsha 410083, China
| | - Huaming Yang
- Hunan
Key Laboratory of Mineral Materials and Application, School of Minerals
Processing and Bioengineering, Central South
University, Changsha 410083, China
- Engineering
Research Center of Nano-Geomaterials of Ministry of Education, China University of Geosciences, Wuhan 430074, China
- Laboratory
of Advanced Mineral Materials, China University
of Geosciences, Wuhan 430074, China
- Faculty of
Materials Science and Chemistry, China University
of Geosciences, Wuhan 430074, China
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Chaoui A, Farsad S, Ben Hamou A, Amjlef A, Nouj N, Ezzahery M, El Alem N. Reshaping environmental sustainability: Poultry by-products digestate valorization for enhanced biochar performance in methylene blue removal. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 351:119870. [PMID: 38141348 DOI: 10.1016/j.jenvman.2023.119870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/08/2023] [Accepted: 12/13/2023] [Indexed: 12/25/2023]
Abstract
Anaerobic digestion is a highly effective and innovative method for treating organic waste while simultaneously generating energy. However, the treatment of the resulting digestate remains a challenging endeavor. To address this issue, poultry by-products digestate is used in this study to prepare biochars at two different pyrolysis temperatures (500/600 °C). Despite their potential, the utilization of untreated biochar is restricted due to its inadequate adsorption capacity. Therefore, each biochar was chemically activated using either HNO3 or KOH to synthesize four activated biochars (BC5@KOH, BC6@HNO3, BC5@HNO3, and BC6@HNO3). The aim is to investigate how the nature of chemical activation and pyrolysis temperature influence the adsorption of methylene blue dye. Characterization techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), Raman analysis, and pHpzc determination, were exploited to comprehensively elucidate the structure and composition of both unprocessed and chemically activated biochars. Among the activated biochars, the adsorbent BC5@HNO3 exhibits the highest methylene blue (MB) adsorption capacity, reaching 101.72 mg.g-1 at 298 K under (pH = 2, ads dose = 0.6 g.L-1, shaking time of 20 min, as optimal conditions for MB adsorption. Adsorption data for each adsorbent strongly aligns with both the Langmuir isotherm model and the pseudo-second-order kinetic model. Moreover, the thermodynamic study reveals that the adsorption process was endothermic and spontaneous. The adsorption mechanism of MB dye was explored using various analytical techniques, including FTIR, SEM, PZC, and pH impact assessment. The findings suggest correlations with electrostatic interactions, hydrogen bonding, pore filling, as well as n-π and π-π interactions. Apparently, activated biochars play a crucial role in efficiently removing methylene blue dye, showcasing their potential as environmentally friendly and effective adsorbents.
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Affiliation(s)
- Ayoub Chaoui
- Laboratory of Materials and Environment, Faculty of Sciences, Ibnou Zohr University, Agadir, Morocco.
| | - Salaheddine Farsad
- Laboratory of Materials and Environment, Faculty of Sciences, Ibnou Zohr University, Agadir, Morocco
| | - Aboubakr Ben Hamou
- Laboratory of Materials and Environment, Faculty of Sciences, Ibnou Zohr University, Agadir, Morocco
| | - Asma Amjlef
- Laboratory of Materials and Environment, Faculty of Sciences, Ibnou Zohr University, Agadir, Morocco
| | - Nisrine Nouj
- Laboratory of Materials and Environment, Faculty of Sciences, Ibnou Zohr University, Agadir, Morocco
| | - Mohamed Ezzahery
- Laboratory of Materials and Environment, Faculty of Sciences, Ibnou Zohr University, Agadir, Morocco
| | - Noureddine El Alem
- Laboratory of Materials and Environment, Faculty of Sciences, Ibnou Zohr University, Agadir, Morocco
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Shafiq F, Liu C, Zhou H, Chen H, Yu S, Qiao W. Stearic acid-modified hollow hydroxyapatite particles with enhanced hydrophobicity for oil adsorption from oil spills. CHEMOSPHERE 2024; 348:140651. [PMID: 37995975 DOI: 10.1016/j.chemosphere.2023.140651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 10/12/2023] [Accepted: 11/06/2023] [Indexed: 11/25/2023]
Abstract
Oil spills lead to a substantial depletion of aquatic biodiversity. The mitigation of an oil spill can entail considerable financial outlays, give rise to consequential environmental impacts, and present formidable operational complexities. In this research, hollow hydroxyapatite particles with enhanced oil adsorption characteristics were prepared by surface modification with stearic acid. Peanut and vacuum pump oils were used to imitate oil spills and conduct adsorption tests. The 50% stearic acid-modified hydroxyapatite (Sa/HAP) adsorbent showed superior hydrophobic properties with respect to water contact angle data. Adsorption isotherm analysis revealed that the adsorption processes of peanut and vacuum pump oils matched well with the Sips isotherm model, with regression coefficients of 0.992 and 0.996, respectively. The oil adsorption by the modified hydroxyapatite (HAP) adsorbent was found to be 9.85 g·g-1 for peanut oil and 12.13 g·g-1 for vacuum pump oil. Furthermore, the adsorption kinetics performance was determined by chemical interaction, whereas the adsorption equilibrium capacities were 8.97 g·g-1 and 11.41 g·g-1, respectively. Recycling of the spent adsorbent was performed with toluene stripping. The synthesized oil-adsorbents were analyzed by SEM, FTIR, XRD, contact angle, and TGA analyses. Hence, the efficacy of the Sa/HAP material as a potential adsorbent for the purification of oil-contaminated water was established, attributed to its commendable oil adsorption capability.
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Affiliation(s)
- Farishta Shafiq
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, PR China
| | - Chenyu Liu
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, PR China.
| | - Hengjun Zhou
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, PR China
| | - Hailiang Chen
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, PR China
| | - Simiao Yu
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, PR China
| | - Weihong Qiao
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, PR China.
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Ma L, Liu W, Liu B, Tang Y. Removal of methylene blue by acrylic polymer adsorbents loaded with magnetic iron manganese oxides: Synthesis, characterization, and adsorption mechanisms. CHEMOSPHERE 2024; 346:140588. [PMID: 37914049 DOI: 10.1016/j.chemosphere.2023.140588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 10/13/2023] [Accepted: 10/28/2023] [Indexed: 11/03/2023]
Abstract
Dyes pose significant risks for aquatic environments and biological health in general owing to their non-biodegradable nature, carcinogenicity, and toxicity. The effective treatment of dye wastewater has become an important research topic. In this study, acrylic polymers (AP) loaded with magnetic iron manganese oxides (MIMO) (AP/MIMO) were prepared and used for the first time for the adsorption of methylene blue (MB). Carbon in AP/MIMO exists predominantly in the C-H and C-C forms, with its content reaching 50.7%. Oxygen and nitrogen in AP/MIMO exist mainly in the -CO- and -N-C forms, with contents of up to 41.5% and 73.3%, respectively. MB removal by AP/MIMO was consistent with the pseudo-second-order kinetic model (R2 = 0.99), equilibrium was achieved within 20 min, and the highest MB capacity of 2611.23 mg g-1 was predicted by the Langmuir isotherm model (R2 = 0.91-0.94). AP/MIMO exhibited excellent MB adsorption performance in the pH range of 4-10, with a removal efficiency higher than 99.0% (MB = 100 mL 1000 mg L-1; AP/MIMO = 50 mg). Thermodynamic indicators, such as positive entropy (ΔS0; 98.30 J⋅mol-1⋅K-1), negative Gibbs free energy (ΔG0; -29.40, -28.50, and -27.50 KJ⋅mol-1), and positive enthalpy (ΔH0; 2.30 KJ⋅mol-1), demonstrated that MB removal by AP/MIMO was autonomous, favorable, and endothermic. In addition, the integration of experimental results and theoretical calculations verified that electrostatic interactions were the primary mechanism for MB adsorption at carboxyl sites on AP/MIMO. The total interaction energy between AP and MB was -310.43 kJ⋅mol-1, and the electrostatic effect had a decisive contribution to the MB adsorption, with a value of up to -341.06 kJ⋅mol-1. AP and MB were most likely bound by -COO and S atoms. Overall, AP/MIMO exhibits high adsorption capacity and shows potential as a high-performance magnetic polymer for MB removal.
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Affiliation(s)
- Lixin Ma
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China; School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Weirong Liu
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, China
| | - Baozhen Liu
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, China
| | - YingCai Tang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing, 100084, China.
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