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Li D, Luo X, Shao P, Meng Z, Yao Z, Yang L, Shao J, Dong H, Zhang L, Zeng L, Luo X. Tuning electronic structure of the carbon skeleton to accelerate electron transfer for promoting the capture of gold. ENVIRONMENT INTERNATIONAL 2023; 180:108192. [PMID: 37741004 DOI: 10.1016/j.envint.2023.108192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 08/29/2023] [Accepted: 09/05/2023] [Indexed: 09/25/2023]
Abstract
The efficient and selective recovery of gold from secondary sources is key to sustainable development. However, the complexity of the recovery environment can significantly complicate the compositions of utilized sorbents. Here, we report a straw-derived mesoporous carbon as an inexpensive support material. This mesoporous carbon is modified by anions (sulfur modulation, C-S-180) to improve its electron-transfer efficiency and tune the electronic structure of its skeleton toward enhanced gold reduction. The high surface area of C-S-180 (989.4 m2/g), as well as the presence of abundant C-S in the porous structure of the adsorbent, resulted in an outstanding Au3+-uptake capacity (3422.75 mg/g), excellent resistance to interference, and favorable Au3+ selectivity. Dissimilar to most existing carbon-based adsorbents, electrochemistry-based studies on the electron-transfer efficiencies of adsorbents reveal that sulfur modulation is crucial to optimizing their adsorption performances. Furthermore, the density functional theory reveals that the optimization mechanism is attributable to the adjustment of the electronic structure of the carbon skeleton by C-S, which optimizes the band-gap energy for enhanced Au3+ reduction. These findings offer a strategy for constructing green and efficient adsorbents, as well as a basis for extending the applications of inexpensive carbon materials in gold recovery from complex environments.
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Affiliation(s)
- Dewei Li
- National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Xianxin Luo
- National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Penghui Shao
- National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, Nanchang Hangkong University, Nanchang 330063, PR China.
| | - Zhu Meng
- National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Ziwei Yao
- National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Liming Yang
- National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Jiachuang Shao
- National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Hao Dong
- National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Li Zhang
- National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Lingrong Zeng
- National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Xubiao Luo
- National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization, Nanchang Hangkong University, Nanchang 330063, PR China; College of Life Sciences, Jinggangshan University, Jian 343009, PR China.
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New Carbamoyl Surface-Modified ZrO 2 Nanohybrids for Selective Au Extraction from E-Waste. Molecules 2023; 28:molecules28052219. [PMID: 36903468 PMCID: PMC10004478 DOI: 10.3390/molecules28052219] [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: 02/07/2023] [Revised: 02/20/2023] [Accepted: 02/23/2023] [Indexed: 03/04/2023] Open
Abstract
Efficient and selective extractions of precious and critical metal ions such as Au(III) and Pd(II) were investigated using zirconia nanoparticles surface modified with different organic mono- and di-carbamoyl phosphonic acid ligands. The modification is made on the surface of commercial ZrO2 that is dispersed in aqueous suspension and was achieved by optimizing the Bronsted acid-base reaction in ethanol/H2O solution (1:2), resulting in inorganic-organic systems of ZrO2-Ln (Ln: organic carbamoyl phosphonic acid ligand). The presence, binding, amount, and stability of the organic ligand on the surface of zirconia nanoparticles were confirmed by different characterizations such as TGA, BET, ATR-FTIR, and 31P-NMR. Characterizations showed that all the prepared modified zirconia had a similar specific surface area (50 m2.g-1) and the same amount of ligand on the zirconia surface in a 1:50 molar ratio. ATR-FTIR and 31P-NMR data were used to elucidate the most favorable binding mode. Batch adsorption results showed that (i) ZrO2 surface modified with di-carbamoyl phosphonic acid ligands had the highest adsorption efficiency to extract metals than mono-carbamoyl ligands, and (ii) higher hydrophobicity of the ligand led to better adsorption efficiency. The surface-modified ZrO2 with di-N,N-butyl carbamoyl pentyl phosphonic acid ligand (ZrO2-L6) showed promising stability, efficiency, and reusability in industrial applications for selective gold recovery. In terms of thermodynamic and kinetic adsorption data, ZrO2-L6 fits the Langmuir adsorption model and pseudo-second-order kinetic model for the adsorption of Au(III) with maximum experimental adsorption capacity qmax = 6.4 mg.g-1.
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Selective and Effective Gold Recovery from Printed Circuit Boards and Gold Slag Using Amino-Acid-Functionalized Cellulose Microspheres. Polymers (Basel) 2023; 15:polym15020321. [PMID: 36679202 PMCID: PMC9863566 DOI: 10.3390/polym15020321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 12/31/2022] [Accepted: 01/02/2023] [Indexed: 01/10/2023] Open
Abstract
The hydrometallurgical recovery of gold from electronic waste and gold slag is a hot research topic. To develop a cost-effective and environmentally friendly adsorbent for gold recovery, four types of amino-acid (arginine, histidine, methionine, and cysteine)-functionalized cellulose microspheres were prepared via a radiation technique. The adsorption performance of the amino acid resins toward Au(III) ions was systematically investigated by batch experiments. The amino acid resins could absorb Au(III) ions at a wide pH range. The adsorption process was followed by the pseudo-second-order model and Langmuir model. The theoretical maximum adsorption capacity was calculated as 396.83 mg/g, 769.23 mg/g, 549.45 mg/g, and 636.94 mg/g for ArgR, HisR, MetR, and CysR, respectively. The amino acid resins could effectively and selectively recover trace Au(III) ions from the leaching solutions of printed circuit board and gold slag waste. Lastly, the mechanism underlying amino acid resin's Au(III) ion recovery capability was investigated by FTIR, XRD, and XPS analyses. This work describes a series of cost-effective gold adsorbents with excellent selectivity and adsorption capacity to boost their practical application.
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Chakraborty D, Devi M, Das B, Dhar SS. Core-shell assembly of ZrO 2 nanoparticles with ionic liquid: a novel and highly efficient heterogeneous catalysts for Biginelli and esterification reactions. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:13846-13861. [PMID: 36149562 DOI: 10.1007/s11356-022-23136-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Imidazolium sulfonic acid chloride grafted ZrO2 nanoparticles (ZrO2-IL) were synthesized through facile post-treatment of the nanoparticles with the imidazolium-sulfonic acid chloride ionic liquid. The immobilization of the ionic liquid over the ZrO2 nanoparticles was evident from the XRD, SEM, TEM, Raman, BET, and XPS analysis. The results obtained from the XRD analysis clearly show that the catalyst has an orthorhombic structure and from the BET analysis it is evident that the surface is mesoporous with uniform pore sizes and pore distribution. Further evidence of immobilization of ionic liquid over the ZrO2 NPs was obtained from the SEM, TEM, XPS, and Raman analysis. Under mild conditions, the synthesized heterostructure was used in the acid-catalyzed esterification of different acids. The ZrO2-IL catalyst converts 99% of the acid to ester with a 98.9% yield in 1h. The material was also shown to be highly efficient as catalyst for the Biginelli reaction under solvent-free conditions, with the catalyst for dihydropyrimidin-2(1H)-one (DHPMs) in 1h with 99.2% conversion and 99% yield. The synergy between the ionic liquid catalyst and the substrates increased the catalytic efficiency and resulted in high-yield product conversion. The mechanism of both transformation reactions was investigated, as well as the synergy between ionic liquid and ZrO2 nanoparticles for better catalytic efficiency was established.
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Affiliation(s)
- Debarati Chakraborty
- Department of Chemistry, National Institute of Technology, Assam, 788010, Silchar, India
| | - Meghali Devi
- Department of Chemistry, National Institute of Technology, Assam, 788010, Silchar, India
| | - Bishal Das
- Department of Chemistry, National Institute of Technology, Assam, 788010, Silchar, India
| | - Siddhartha Sankar Dhar
- Department of Chemistry, National Institute of Technology, Assam, 788010, Silchar, India.
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Mossand G, Lelong E, Xing C, Ndebulia Watchou F, Leydier A, Arrachart G, Pellet-Rostaing S. Bis-Catecholamide-Based Materials for Uranium Extraction. Chempluschem 2022; 88:e202200412. [PMID: 36638257 DOI: 10.1002/cplu.202200412] [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: 11/17/2022] [Revised: 12/21/2022] [Indexed: 12/24/2022]
Abstract
This work reports the synthesis of formo-phenolic resins containing four catecholamide (CAM) moieties with admixture of phenol, catechol or resorcinol. These chelating resins have been developed to selectively extract U(VI) from seawater. This media is a challenging environment due to a pH around 8.2 and a large excess of alkaline and earth-alkaline cations. From the various sorption experiments investigated, the results indicate that the synthesized material exhibit good sorbent properties for U(VI) with uptake capacity about 50 mg/g for the more promising resins with a pronounced selectivity for uranium even under saline conditions. Thermodynamic and kinetic adsorption data were determined for the best resin (Langmuir adsorption model and pseudo-second order model).
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Affiliation(s)
- Guillaume Mossand
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, 30207, Bagnols sur Cèze Cedex, France
| | - Evan Lelong
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, 30207, Bagnols sur Cèze Cedex, France
| | - Chen Xing
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, 30207, Bagnols sur Cèze Cedex, France
| | | | - Antoine Leydier
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, 30207, Bagnols sur Cèze Cedex, France
| | - Guilhem Arrachart
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, 30207, Bagnols sur Cèze Cedex, France
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Gys N, Pawlak B, Lufungula LL, Marcoen K, Wyns K, Baert K, Atia TA, Spooren J, Adriaensens P, Blockhuys F, Hauffman T, Meynen V, Mullens S, Michielsen B. Selective Pd recovery from acidic leachates by 3-mercaptopropylphosphonic acid grafted TiO 2: does surface coverage correlate to performance? RSC Adv 2022; 12:36046-36062. [PMID: 36545072 PMCID: PMC9756939 DOI: 10.1039/d2ra07214a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
Modification of metal oxides with organophosphonic acids (PAs) provides the ability to control and tailor the surface properties. The metal oxide phosphonic acid bond (M-O-P) is known to be stable under harsh conditions, making PAs a promising candidate for the recovery of metals from complex acidic leachates. The thiol functional group is an excellent regenerable scavenging group for these applications. However, the research on organophosphonic acid grafting with thiol groups is very limited. In this study, four different metal sorbent materials were designed with different thiol surface coverages. An aqueous-based grafting of 3-mercaptopropylphosphonic acid (3MPPA) on mesoporous TiO2 was employed. Surface grafted thiol groups could be obtained in the range from 0.9 to 1.9 groups per nm2. The different obtained surface properties were studied and correlated to the Pd adsorption performance. High Pd/S adsorption efficiencies were achieved, indicating the presence of readily available sorption sites. A large difference in their selectivity towards Pd removal from a spend automotive catalyst leachate was observed due to the co-adsorption of Fe on the titania support. The highest surface coverage showed the highest selectivity (K d: 530 mL g-1) and adsorption capacity (Q max: 0.32 mmol g-1) towards Pd, while strongly reducing the co-adsorption of Fe on remaining TiO2 sites.
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Affiliation(s)
- Nick Gys
- Sustainable Materials, Flemish Institute for Technological Research (VITO NV)Boeretang 200Mol 2400Belgium,Laboratory of Adsorption and Catalysis (LADCA), Department of Chemistry, University of Antwerp, Universiteitsplein 1Wilrijk 2610Belgium
| | - Bram Pawlak
- Analytical and Circular Chemistry (ACC), Institute for Materials Research (IMO), Hasselt UniversityAgoralaan 1Diepenbeek 3590Belgium
| | - Léon Luntadila Lufungula
- Structural Chemistry Group, Department of Chemistry, University of AntwerpGroenenborgerlaan 171Antwerp 2020Belgium
| | - Kristof Marcoen
- Research Group Electrochemical and Surface Engineering (SURF), Department Materials and Chemistry, Vrije Universiteit BrusselPleinlaan 2Brussels 1050Belgium
| | - Kenny Wyns
- Sustainable Materials, Flemish Institute for Technological Research (VITO NV)Boeretang 200Mol 2400Belgium
| | - Kitty Baert
- Research Group Electrochemical and Surface Engineering (SURF), Department Materials and Chemistry, Vrije Universiteit BrusselPleinlaan 2Brussels 1050Belgium
| | - Thomas Abo Atia
- Sustainable Materials, Flemish Institute for Technological Research (VITO NV)Boeretang 200Mol 2400Belgium,Department of Chemistry, KU LeuvenCelestijnenlaan 200FLeuven 3000Belgium
| | - Jeroen Spooren
- Sustainable Materials, Flemish Institute for Technological Research (VITO NV)Boeretang 200Mol 2400Belgium
| | - Peter Adriaensens
- Analytical and Circular Chemistry (ACC), Institute for Materials Research (IMO), Hasselt UniversityAgoralaan 1Diepenbeek 3590Belgium
| | - Frank Blockhuys
- Structural Chemistry Group, Department of Chemistry, University of AntwerpGroenenborgerlaan 171Antwerp 2020Belgium
| | - Tom Hauffman
- Research Group Electrochemical and Surface Engineering (SURF), Department Materials and Chemistry, Vrije Universiteit BrusselPleinlaan 2Brussels 1050Belgium
| | - Vera Meynen
- Sustainable Materials, Flemish Institute for Technological Research (VITO NV)Boeretang 200Mol 2400Belgium,Laboratory of Adsorption and Catalysis (LADCA), Department of Chemistry, University of Antwerp, Universiteitsplein 1Wilrijk 2610Belgium
| | - Steven Mullens
- Sustainable Materials, Flemish Institute for Technological Research (VITO NV)Boeretang 200Mol 2400Belgium
| | - Bart Michielsen
- Sustainable Materials, Flemish Institute for Technological Research (VITO NV)Boeretang 200Mol 2400Belgium
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Recovery of Palladium and Gold from PGM Ore and Concentrates Using ZnAl-Layered Double Hydroxide@zeolitic Imidazolate Framework-8 Nanocomposite. SEPARATIONS 2022. [DOI: 10.3390/separations9100274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Gold (Au) and palladium (Pd) are platinum group metals (PGMs) that are considered critical in society because they are required in several industrial applications. Their shortage has caused the urgent need for their recovery from secondary resources. Therefore, there is a need to develop functional materials with high adsorption capacity and selectivity for recovery of PGMs from various secondary sources. In this study, a Zn-Al-layered double hydroxide@zeolitic imidazolate framework-8 (Zn–Al–LDH@ZIF–8) nanocomposite was used as an adsorbent for the recovery of Au and Pd from ore concentrates. The Zn–Al–LDH@ZIF–8 nanocomposite was characterised using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, zeta potential, and X-ray diffraction (XRD) spectroscopy. The recovery of Au(III) and Pd(II) was achieved using ultrasound-assisted dispersive µ-solid-phase extraction (UA-D-µ-SPE) and their quantification was attained using an inductively coupled plasma mass spectrometer (ICP-MS). The results showed that the surface of the adsorbent remained positively charged in a wide pH range, which endowed the nanocomposite with high adsorption affinity towards Au(III) and Pd(II). Under optimised conditions, the equilibrium studies revealed that the adsorption of Au(III) and Pd(II) ions followed the Langmuir isotherm model with maximum sorption capacities of 163 mg g−1 and 177 mg g−1 for Au(III) and Pd(II), respectively. The nanocomposite possessed relatively good regeneration, reusability, and stability characteristics, with its performance decreasing by only 10% after five adsorption–desorption cycles.
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Terephthalaldehyde-Phenolic Resins as a Solid-Phase Extraction System for the Recovery of Rare-Earth Elements. Polymers (Basel) 2022; 14:polym14020311. [PMID: 35054717 PMCID: PMC8780303 DOI: 10.3390/polym14020311] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/06/2022] [Accepted: 01/07/2022] [Indexed: 12/10/2022] Open
Abstract
Rare-earth elements (REEs) are involved in most high technology devices and have become critical for many countries. The progress of processes for the extraction and recovery of REEs is therefore essential. Liquid–solid extraction methods are an attractive alternative to the conventional solvent extraction process used for the separation and/or purification of REEs. For this purpose, a solid-phase extraction system was investigated for the extraction and valorization of REEs. Ion-exchange resins were synthesized involving the condensation of terephthalaldehyde with resorcinol under alkaline conditions. The terephthalaldehyde, which is a non-hazardous aromatic dialdehyde, was used as an alternative to formaldehyde that is toxic and traditionally involved to prepare phenolic ion-exchange resins. The resulting formaldehyde-free resole-type phenolic resins were characterized and their ion-exchange capacity was investigated in regard to the extraction of rare-earth elements. We herein present a promising formaldehyde and phenol-free as a potential candidate for solid–liquid extraction REE with a capacity higher than 50 mg/g and the possibility to back-extract the REEs by a striping step using a 2 M HNO3 solution.
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In-situ benzoxazine-isocyanide chemistry (BIC)/sol-gel preparation and Pb(II) electrochemical probing investigation of modified polyamide/silica composite. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2021.127798] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Jiang L, Liu Y, Meng X, Xian M, Xu C. Adsorption behavior study and mechanism insights into novel isothiocyanate modified material towards Pd2+. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119514] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Ultrahigh and selective adsorption of Au(III) by rich sulfur and nitrogen-bearing cellulose microspheres and their applications in gold recovery from gold slag leaching solution. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119016] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Adsorptive recovery of precious metals from aqueous solution using nanomaterials – A critical review. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214072] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Design of Hybrid PAH Nanoadsorbents by Surface Functionalization of ZrO 2 Nanoparticles with Phosphonic Acids. NANOMATERIALS 2021; 11:nano11040952. [PMID: 33917895 PMCID: PMC8068232 DOI: 10.3390/nano11040952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/01/2021] [Accepted: 04/02/2021] [Indexed: 11/16/2022]
Abstract
This study focuses on the preparation of innovative nanocomposite materials based on surface modification of commercial nano-ZrO2 optimized from Brønsted acid-base surface reactions. This surface modification was carried out by direct grafting of suitable phosphonic acids bearing a vinylic or phenylic substituent in aqueous solution. Different loading quantities of the anchoring organophosphorus compounds were applied for each materials synthesis. The resulting nanohybrids were thoroughly characterized by infrared spectroscopy (DRIFT), solid-state nuclear magnetic resonance (NMR), nitrogen adsorption-desorption (BET), thermogravimetric analysis (TG), and X-ray photoelectron spectroscopy (XPS), demonstrating the reliability and efficient tunability of the surface functionalization based on the starting Zr/P ratio. Our nanocomposite materials exhibited a high specific surface area as well as complex porosity networks with well-defined meso-pore. The as-prepared materials were investigated for the adsorption of a mixture of 16 polycyclic aromatic hydrocarbons (PAHs) at 200 ng·mL-1 in an aqueous solution. Adsorption kinetics experiments of each individual material were carried out on the prepared PAHs standard solution for a contact time of up to 6 h. Pretreatments of the adsorption test samples were performed by solid-phase extraction (SPE), and the resulting samples were analyzed using an ultrasensitive GC-orbitrap-MS system. The pseudo-first-order and the pseudo-second-order models were used to determine the kinetic data. The adsorption kinetics were best described and fitted by the pseudo-second-order kinetic model. The correlation between the nature of the substituent (vinylic or phenylic) and the parameters characterizing the adsorption process were found. In addition, an increase of PAHs adsorption rates with phosphonic acid loading was observed.
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