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Bian JJ, Tang SJ, Miao J, Lin R, Huang GL, Teng MY, Li XM. Synthesis of supramolecular polymers with calix[4]arene and β-cyclodextrin and their application in heavy metal ion absorption. RSC Adv 2024; 14:35697-35703. [PMID: 39524092 PMCID: PMC11545913 DOI: 10.1039/d4ra05559d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2024] [Accepted: 10/28/2024] [Indexed: 11/16/2024] Open
Abstract
Two categories of supramolecular polymer monomers were produced by introducing the ureidopyrimidone quadruple-hydrogen bonding assemblies on the calix[4]arene and the β-cyclodextrin host units. The adsorption capacity of these supramolecular polymers for different metal ions was investigated by static adsorption. The results showed that at pH = 6 and when the adsorption equilibrium was reached, the supramolecular polymer with calixarene and β-cyclodextrin as the main body adsorbed up to 99% of Pb2+ and Cd2+, respectively. Also, the supramolecular polymer connected with six carbon chains on β-cyclodextrin had better recognition of Cd2+ and Pb2+, and the highest adsorption rate reached 99%. Industrial adsorbent materials from such supramolecular polymers will provide more options for water pollution control, especially for heavy metal ions.
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Affiliation(s)
- Jian-Jian Bian
- Faculty of Chemistry and Chemical Engineering, Yunnan Normal University Kunming 650500 China +86 871 65941088 +86 871 65941087
| | - Shi-Jin Tang
- Faculty of Chemistry and Chemical Engineering, Yunnan Normal University Kunming 650500 China +86 871 65941088 +86 871 65941087
| | - Jiao Miao
- Faculty of Chemistry and Chemical Engineering, Yunnan Normal University Kunming 650500 China +86 871 65941088 +86 871 65941087
| | - Rui Lin
- Image and Text Information Center, Yunnan Normal University Kunming 650500 China +86 871 65912939 +86 871 65912939
| | - Guo-Li Huang
- Faculty of Chemistry and Chemical Engineering, Yunnan Normal University Kunming 650500 China +86 871 65941088 +86 871 65941087
| | - Ming-Yu Teng
- Faculty of Chemistry and Chemical Engineering, Yunnan Normal University Kunming 650500 China +86 871 65941088 +86 871 65941087
| | - Xiao-Mei Li
- Faculty of Chemistry and Chemical Engineering, Yunnan Normal University Kunming 650500 China +86 871 65941088 +86 871 65941087
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Salehpour N, Bayatloo MR, Nojavan S. Green hydrophobic maltodextrin nanosponges for magnetic solid-phase extraction of hypothalamic peptides from plasma samples. J Chromatogr A 2023; 1706:464220. [PMID: 37523906 DOI: 10.1016/j.chroma.2023.464220] [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: 04/29/2023] [Revised: 07/03/2023] [Accepted: 07/17/2023] [Indexed: 08/02/2023]
Abstract
In this work, for the first time, magnetic-phthalated maltodextrin nanosponges (M-PAMDNSs) were synthetized and introduced as efficient and green sorbents. The integration of phthaloyl groups as hydrophobic moieties into networks of maltodextrin nanosponges provided good enrichment for hypothalamic-related peptides (HRPs). The synthesized materials were characterized by 1H nuclear magnetic resonance spectroscopy, water contact angle, attenuated total reflection-Fourier transform infrared spectroscopy, dynamic light scattering, zeta potential, pH point of zero charge, acid-base titration, field-emission scanning electron microscopy, Brunauer-Emmett-Teller, and vibrating sample magnetometer. Under the optimized conditions (sorbent amount: 5.0 mg, desorption solvent volume and type: 300 µL of methanol: H2O: trifluoroacetic acid, extraction time: 15 min, and desorption time: 10 min), the developed magnetic solid-phase extraction (MSPE) method in combination with HPLC-UV was used as a novel and sensitive analytical method for the determination of HRPs in plasma samples. The proposed MSPE-HPLC-UV method provided good linearity (1.5-500 ng mL-1 R2 ≥ 0.9988), low limits of detection (0.1-0.2 ng mL-1) and quantification (0.4-0.8 ng mL-1), desirable precision (RSD ≤ 8.8%, n ₌ 5), satisfactory enrichment factor (EFs ≥ 66.0), and well relative recoveries (92.8-108.8%). Overall, the established method effectively expanded the analytical potential of MSPE approach for the quantification of HRPs in biological samples.
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Affiliation(s)
- Niloofar Salehpour
- Department of Analytical Chemistry and Pollutants, Shahid Beheshti University, Evin, Tehran, Iran
| | - Mohammad Reza Bayatloo
- Department of Analytical Chemistry and Pollutants, Shahid Beheshti University, Evin, Tehran, Iran
| | - Saeed Nojavan
- Department of Analytical Chemistry and Pollutants, Shahid Beheshti University, Evin, Tehran, Iran.
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Anselmo S, Avola T, Kalouta K, Cataldo S, Sancataldo G, Muratore N, Foderà V, Vetri V, Pettignano A. Sustainable soy protein microsponges for efficient removal of lead (II) from aqueous environments. Int J Biol Macromol 2023; 239:124276. [PMID: 37011754 DOI: 10.1016/j.ijbiomac.2023.124276] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/17/2023] [Accepted: 03/28/2023] [Indexed: 04/03/2023]
Abstract
Protein-based materials recently emerged as good candidates for water cleaning applications, due to the large availability of the constituent material, their biocompatibility and the ease of preparation. In this work, new adsorbent biomaterials were created from Soy Protein Isolate (SPI) in aqueous solution using a simple environmentally friendly procedure. Protein microsponge-like structures were produced and characterized by means of spectroscopy and fluorescence microscopy methods. The efficiency of these structures in removing lead (Pb2+) ions from aqueous solutions was evaluated by investigating the adsorption mechanisms. The molecular structure and, consequently, the physico-chemical properties of these aggregates can be readily tuned by selecting the pH of the solution during production. In particular, the presence of β-structures typical of amyloids as well as an environment characterized by a lower dielectric constant seem to enhance metal binding affinity revealing that hydrophobicity and water accessibility of the material are key features affecting the adsorption efficiency. Presented results provide new knowledge on how raw plant proteins can be valorised for the production of new biomaterials. This may offer extraordinary opportunities towards the design and production of new tailorable biosorbents which can also be exploited for several cycles of purification with minimal reduction in performance. SYNOPSIS: Innovative, sustainable plant-protein biomaterials with tunable properties are presented as green solution for water purification from lead (II) and the structure-function relationship is discussed.
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García-López EI, Arcidiacono F, Di Vincenzo A, Palmisano L, Lo Meo P, Marcì G. Nanosponge-C 3N 4 composites as photocatalysts for selective partial alcohol oxidation in aqueous suspension. Photochem Photobiol Sci 2023:10.1007/s43630-023-00394-5. [PMID: 36847924 DOI: 10.1007/s43630-023-00394-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 02/07/2023] [Indexed: 03/01/2023]
Abstract
A set of four composite materials was prepared, consisting of a nanosponge matrix based on β-cyclodextrin in which carbon nitride was dispersed. The materials were characterized by the presence of diverse cross-linker units joining the cyclodextrin moieties, in order to vary the absorption/release abilities of the matrix. The composites were characterized and used as photocatalysts in aqueous medium under UV, visible and natural solar irradiation for the photodegradation of 4-nitrophenol, and for the selective partial oxidation of 5-hydroxymethylfurfural and veratryl alcohol to the corresponding aldehydes. The nanosponge-C3N4 composites showed higher activity than the pristine semiconductor, which can probably be attributed to the synergic effect of the nanosponge, capable of increasing the substrate concentration near the surface of the photocatalyst.
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Affiliation(s)
- Elisa I García-López
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale Delle Scienze, 90128, Palermo, Italy
| | - Federica Arcidiacono
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale Delle Scienze, 90128, Palermo, Italy
| | - Antonella Di Vincenzo
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale Delle Scienze, 90128, Palermo, Italy
| | - Leonardo Palmisano
- "Schiavello-Grillone" Photocatalysis Group. Department of Engineering, University of Palermo, Viale Delle Scienze, 90128, Palermo, Italy.
| | - Paolo Lo Meo
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale Delle Scienze, 90128, Palermo, Italy
| | - Giuseppe Marcì
- "Schiavello-Grillone" Photocatalysis Group. Department of Engineering, University of Palermo, Viale Delle Scienze, 90128, Palermo, Italy.
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Kumar YB, Pandey A, Kumar N, Sastry GN. Binding propensity and selectivity of cationic, anionic, and neutral guests with model hydrophobic hosts: A first principles study. J Comput Chem 2023; 44:432-441. [PMID: 36583416 DOI: 10.1002/jcc.26977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 06/23/2022] [Accepted: 07/21/2022] [Indexed: 01/03/2023]
Abstract
Computations play a critical role in deciphering the nature of host-guest interactions both at qualitative and quantitative levels. Reliable quantum chemical computations were employed to assess the nature, binding strength, and selectivity of ionic, and neutral guests with benzenoid hosts. Optimized complex structures reveal that alkali and ammonium ions are found to be in the hydrophobic cavity, while halide ions are outside, while both complexes elicit substantial binding energy. The origin of the selectivity of host toward the guest has been traced to the interaction and deformation energies, and the nature of associated interactions is quantified using energy decomposition and the Quantum Theory of Atoms in Molecules analyses. While the larger hosts lead to loosely bound complexes, as assessed by the longer intermolecular distances, the binding strengths are proportional to the size of the host systems. The binding of cationic complexes is electrostatic or polarization driven while exchange term dominates the anionic complexes. In contrast, dispersion contribution is a key in neutral complexes and plays a pivotal role in stabilizing the polyatomic complexes.
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Affiliation(s)
- Yenamareddy Bhargav Kumar
- Advanced Computation and Data Sciences Division, CSIR-North East Institute of Science and Technology, Jorhat, Assam, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
| | - Anwesh Pandey
- Advanced Computation and Data Sciences Division, CSIR-North East Institute of Science and Technology, Jorhat, Assam, India
| | - Nandan Kumar
- Advanced Computation and Data Sciences Division, CSIR-North East Institute of Science and Technology, Jorhat, Assam, India
| | - G Narahari Sastry
- Advanced Computation and Data Sciences Division, CSIR-North East Institute of Science and Technology, Jorhat, Assam, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
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Abstract
Nanosponges have shown promising capabilities for efficient removal of organic/inorganic pollutants from water based on absorption/adsorption and disinfection processes. The application of nanosponges (especially cyclodextrin-based nanosponges) can be considered a cost-effective strategy with minimal energy and time requirements in comparison to other routinely deployed water treatment modalities. These polymers with unique physicochemical properties, architectures, and highly cross-linked three-dimensional networks need to be further explored for removing pollutants with simultaneous eliminations of microbial contaminants from wastewater. Additionally, the surface functionalization of these nanosponges utilizing magnetic, titanium dioxide, and silver nanomaterials can significantly improve their properties for water remediation purposes, although nanosponges altered with carbon nanotubes and metallic nanomaterials/nanocatalysts for water treatment appliances are barely explored. Notably, crucial factors such as adsorbent type/dosage, contact time, competing ions, adsorption isotherm models, kinetics, thermodynamics, and reaction/experimental conditions (e.g., molar ratios, temperature, and pH) are important aspects affecting the adsorption and removal of pollutants using nanosponges. Furthermore, the nanotoxicity and biosafety of these nanosponge-based systems utilized for water treatment should be comprehensively evaluated. Herein, recent advancements in the design and deployment of nanosponge-based systems for removing organic/inorganic pollutants from water and wastewater are deliberated with an emphasis on challenges and perspectives.
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Utzeri G, Matias PMC, Murtinho D, Valente AJM. Cyclodextrin-Based Nanosponges: Overview and Opportunities. Front Chem 2022; 10:859406. [PMID: 35402388 PMCID: PMC8987506 DOI: 10.3389/fchem.2022.859406] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 03/02/2022] [Indexed: 01/18/2023] Open
Abstract
Nanosponges are solid cross-linked polymeric nano-sized porous structures. This broad concept involves, among others, metal organic frameworks and hydrogels. The focus of this manuscript is on cyclodextrin-based nanosponges. Cyclodextrins are cyclic oligomers of glucose derived from starch. The combined external hydrophilicity with the internal hydrophobic surface constitute a unique "microenvironment", that confers cyclodextrins the peculiar ability to form inclusion host‒guest complexes with many hydrophobic substances. These complexes may impart beneficial modifications of the properties of guest molecules such as solubility enhancement and stabilization of labile guests. These properties complemented with the possibility of using different crosslinkers and high polymeric surface, make these sponges highly suitable for a large range of applications. Despite that, in the last 2 decades, cyclodextrin-based nanosponges have been developed for pharmaceutical and biomedical applications, taking advantage of the nontoxicity of cyclodextrins towards humans. This paper provides a critical and timely compilation of the contributions involving cyclodextrins nanosponges for those areas, but also paves the way for other important applications, including water and soil remediation and catalysis.
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Sun J, Zhao X, Sun G, Zhao H, Yan L, Jiang X, Cui Y. Phosphate-crosslinked β-cyclodextrin polymer for highly efficient removal of Pb( ii) from acidic wastewater. NEW J CHEM 2022. [DOI: 10.1039/d1nj05925d] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Novel phosphate-crosslinked β-cyclodextrin polymer was synthesized for highly efficient Pb(ii) removal from acidic wastewater.
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Affiliation(s)
- Junhua Sun
- School of Chemistry and Chemical Engineering, University of Jinan, No. 336 Nanxinzhuang West Road, 250022, Jinan, P. R. China
| | - Xiuxian Zhao
- Institute for Smart Materials & Engineering, University of Jinan, No. 336 Nanxinzhuang West Road, 250022, Jinan, P. R. China
| | - Guoxin Sun
- School of Chemistry and Chemical Engineering, University of Jinan, No. 336 Nanxinzhuang West Road, 250022, Jinan, P. R. China
- Institute for Smart Materials & Engineering, University of Jinan, No. 336 Nanxinzhuang West Road, 250022, Jinan, P. R. China
| | - Heng Zhao
- School of Chemistry and Chemical Engineering, University of Jinan, No. 336 Nanxinzhuang West Road, 250022, Jinan, P. R. China
| | - Liangguo Yan
- School of Water Conservancy and Environment, University of Jinan, No. 336 Nanxinzhuang West Road, 250022, Jinan, P. R. China
| | - Xuchuan Jiang
- Institute for Smart Materials & Engineering, University of Jinan, No. 336 Nanxinzhuang West Road, 250022, Jinan, P. R. China
| | - Yu Cui
- School of Chemistry and Chemical Engineering, University of Jinan, No. 336 Nanxinzhuang West Road, 250022, Jinan, P. R. China
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Anselmo S, Cataldo S, Avola T, Sancataldo G, D'Oca MC, Fiore T, Muratore N, Scopelliti M, Pettignano A, Vetri V. Lead(II) ions adsorption onto amyloid particulates: An in depth study. J Colloid Interface Sci 2021; 610:347-358. [PMID: 34923272 DOI: 10.1016/j.jcis.2021.11.184] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 11/24/2021] [Accepted: 11/28/2021] [Indexed: 01/08/2023]
Abstract
The production of new cost-effective biocompatible sorbent sustainable materials, with natural origins, able to remove heavy metals from water resources is nowadays highly desirable in order to reduce pollution and increase clean water availability. In this context, self-assembled protein materials with amyloid structures seem to have a great potential as natural platform for a broader development of highly-tunable structures. In this work we show how protein particulates, a generic form of protein aggregates, with spherical micro sized shape can be used as adsorbents of Pb2+ ions from aqueous solution. The effect of pH, ionic medium, ionic strength and temperature of the metal ion solution on the adsorption ability and affinity has been evaluated revealing the complexity of adsorption mechanisms which are the result of the balance of specific interactions with functional groups in protein structure and not specific ones common to all polypeptide chains, and possibly related to amyloid state and to modification of particulates hydration layer.
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Affiliation(s)
- Sara Anselmo
- Dipartimento di Fisica e Chimica - Emilio Segrè, Università di Palermo, Viale delle Scienze, Palermo I-90128, Italy
| | - Salvatore Cataldo
- Dipartimento di Fisica e Chimica - Emilio Segrè, Università di Palermo, Viale delle Scienze, Palermo I-90128, Italy
| | - Tiziana Avola
- Dipartimento di Fisica e Chimica - Emilio Segrè, Università di Palermo, Viale delle Scienze, Palermo I-90128, Italy
| | - Giuseppe Sancataldo
- Dipartimento di Fisica e Chimica - Emilio Segrè, Università di Palermo, Viale delle Scienze, Palermo I-90128, Italy
| | - Maria Cristina D'Oca
- Dipartimento di Fisica e Chimica - Emilio Segrè, Università di Palermo, Viale delle Scienze, Palermo I-90128, Italy
| | - Tiziana Fiore
- Dipartimento di Fisica e Chimica - Emilio Segrè, Università di Palermo, Viale delle Scienze, Palermo I-90128, Italy
| | - Nicola Muratore
- Dipartimento di Fisica e Chimica - Emilio Segrè, Università di Palermo, Viale delle Scienze, Palermo I-90128, Italy
| | - Michelangelo Scopelliti
- Dipartimento di Fisica e Chimica - Emilio Segrè, Università di Palermo, Viale delle Scienze, Palermo I-90128, Italy
| | - Alberto Pettignano
- Dipartimento di Fisica e Chimica - Emilio Segrè, Università di Palermo, Viale delle Scienze, Palermo I-90128, Italy.
| | - Valeria Vetri
- Dipartimento di Fisica e Chimica - Emilio Segrè, Università di Palermo, Viale delle Scienze, Palermo I-90128, Italy.
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Alzahrani FM, Alsaiari NS, Katubi KM, Amari A, Elkhaleefa AM, Rebah FB, Tahoon MA. Magnetic Nitrogen-Doped Porous Carbon Nanocomposite for Pb(II) Adsorption from Aqueous Solution. Molecules 2021; 26:4809. [PMID: 34443398 PMCID: PMC8401485 DOI: 10.3390/molecules26164809] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/05/2021] [Accepted: 08/06/2021] [Indexed: 11/16/2022] Open
Abstract
We report in the present study the in situ formation of magnetic nanoparticles (Fe3O4 or Fe) within porous N-doped carbon (Fe3O4/N@C) via simple impregnation, polymerization, and calcination sequentially. The synthesized nanocomposite structural properties were investigated using different techniques showing its good construction. The formed nanocomposite showed a saturation magnetization (Ms) of 23.0 emu g-1 due to the implanted magnetic nanoparticles and high surface area from the porous N-doped carbon. The nanocomposite was formed as graphite-type layers. The well-synthesized nanocomposite showed a high adsorption affinity toward Pb2+ toxic ions. The nanosorbent showed a maximum adsorption capacity of 250.0 mg/g toward the Pb2+ metallic ions at pH of 5.5, initial Pb2+ concentration of 180.0 mg/L, and room temperature. Due to its superparamagnetic characteristics, an external magnet was used for the fast separation of the nanocomposite. This enabled the study of the nanocomposite reusability toward Pb2+ ions, showing good chemical stability even after six cycles. Subsequently, Fe3O4/N@C nanocomposite was shown to have excellent efficiency for the removal of toxic Pb2+ ions from water.
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Affiliation(s)
- Fatimah Mohammed Alzahrani
- Chemistry Department, College of Science, Princess Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia;
| | - Norah Salem Alsaiari
- Chemistry Department, College of Science, Princess Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia;
| | | | - Abdelfattah Amari
- Department of Chemical Engineering, College of Engineering, King Khalid University, Abha 61411, Saudi Arabia;
- Research Laboratory of Energy and Environment, Department of Chemical Engineering, National School of Engineers, Gabes University, Gabes 6072, Tunisia
| | - Abubakr M. Elkhaleefa
- Department of Chemical Engineering, College of Engineering, King Khalid University, Abha 61411, Saudi Arabia;
| | - Faouzi Ben Rebah
- Higher Institute of Biotechnology of Sfax (ISBS), Sfax University, P.O. Box 263, Sfax 3000, Tunisia;
| | - Mohamed A. Tahoon
- Department of Chemistry, College of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia;
- Chemistry Department, Faculty of Science, Mansoura University, Mansoura 35516, Egypt
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Pectin/Activated Carbon-Based Porous Microsphere for Pb 2+ Adsorption: Characterization and Adsorption Behaviour. Polymers (Basel) 2021; 13:polym13152453. [PMID: 34372055 PMCID: PMC8347585 DOI: 10.3390/polym13152453] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Revised: 07/06/2021] [Accepted: 07/07/2021] [Indexed: 01/24/2023] Open
Abstract
The development of effective heavy metal adsorbents has always been the goal of environmentalists. Pectin/activated carbon microspheres (P/ACs) were prepared through simple gelation without chemical crosslinking and utilized for adsorption of Pb2+. Scanning electron microscopy (SEM) revealed that the addition of activated carbon increased the porosity of the microsphere. Texture profile analysis showed good mechanical strength of P/ACs compared with original pectin microspheres. Kinetic studies found that the adsorption process followed a pseudo-second-order model, and the adsorption rate was controlled by film diffusion. Adsorption isotherms were described well by a Langmuir isotherm model, and the maximum adsorption capacity was estimated to be 279.33 mg/g. The P/ACs with the highest activated carbon (P/AC2:3) maintained a removal rate over 95.5% after 10 adsorption/desorption cycles. SEM-energy-dispersive X-ray spectrum and XPS analysis suggested a potential mechanism of adsorption are ion exchange between Pb2+ and Ca2+, electronic adsorption, formation of complexes, and physical adsorption of P/ACs. All the above results indicated the P/ACs may be a good candidate for the adsorption of Pb2+.
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