Facile Preparation of Hierarchically Porous Aromatic-cyclodextrin Polymers and Their Application for the Selective Adsorption of Cationic Dyes

Abstract Porous β-cyclodextrin-containing materials have significant potential as adsorbents for the removal of pollutants from water. However, preparing these porous polymers in the aqueous phase is challenging. In this study, a kind of novel porous aromatic-cyclodextrin polymers (P-aro-CDPs) was designed and synthesized in aqueous solution under mild conditions by exploiting covalence-crosslinking reaction. P-aro-CDPs were characterized using a variety of methods, which revealed that P-aro-CDPs have a hierarchical porous structure, a highly negatively charged surface, and rich in hydroxyl groups. The prepared P-aro-CDPs showed excellent removal efficiency for methylene blue, with a maximum adsorption capacity of 194.17 mg g-1. The adsorption data are well fitted to the pseudo-second-order kinetic model and the Langmuir isotherm. The as-synthesized P-aro-CDPs material exhibited superior adsorption selection toward cationic dyes than anionic dyes whether in single or multicomponent systems. Further, the P-aro-CDPs adsorbent are reusable, and good performance over six adsorption–desorption cycles was demonstrated. Due to its off-the-beaten-path synthesis, low cost, excellent removal efficiency, and recyclability, P-aro-CDPs have great potential for use as an adsorbent in water-treatment applications.

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Efficient and Selective Adsorption of Gold Ions from Wastewater with Polyaniline Modified by Trimethyl Phosphate: Adsorption Mechanism and Application

Polymers ◽

10.3390/polym11040652 ◽

2019 ◽

Vol 11 (4) ◽

pp. 652 ◽

Cited By ~ 5

Author(s):

Wang ◽

Zhao ◽

Wang ◽

Zhang ◽

Zhang

Keyword(s):

Adsorption Capacity ◽

Adsorption Process ◽

Selective Adsorption ◽

Interaction Mechanism ◽

Single Layer ◽

Phosphate Adsorption ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Trimethyl Phosphate ◽

Selective Recovery

The selective recovery of gold from wastewater is necessary because it is widely used in various fields. In this study, a new polymeric adsorbent (TP-AFC) was prepared by modifying polyaniline with trimethyl phosphate for the selective recovery of gold from wastewater. Bath experiments were carried out to explore the adsorption capacity and mechanism. The optimum pH of adsorption is 4. The adsorption equilibrium is reached at 840 min. The maximum adsorption capacity is 881 mg/g and the adsorption was a spontaneous endothermic process. The adsorption process fitted well with pseudo second-order kinetic and the Langmuir-models. The single-layer chemisorption governed the adsorption process. In addition, the application in wastewater indicated that the interfering ions had no effect on the adsorption of gold ions. TP-AFC has good selectivity. The interaction mechanism was mainly ion exchange and complexation. In general, TP-AFC was successfully prepared and has an excellent future in practical application.

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Adsorptive removal of phosphate by a Fe–Mn–La tri-metal composite sorbent: Adsorption capacity, influence factors, and mechanism

Adsorption Science & Technology ◽

10.1177/0263617420942709 ◽

2020 ◽

Vol 38 (7-8) ◽

pp. 254-270

Author(s):

Yuanrong Zhu ◽

Xianming Yue ◽

Fazhi Xie

Keyword(s):

Aqueous Solutions ◽

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Phosphate Removal ◽

Maximum Adsorption Capacity ◽

Hydroxyl Groups ◽

Metal Composite ◽

Order Kinetic ◽

Composite Sorbent ◽

Composite Adsorbent

Reducing input of phosphorus is the key step for control of eutrophication and algal blooming in freshwater lakes. Adsorption technology is a cost-effective technology for phosphate removal in water for the purpose. Thus, in this study, a novel Fe–Mn–La tri-metal composite sorbent was developed, and then evaluated for phosphate removal. The results showed that the maximum adsorption capacity could be approached to 61.80 mg g−1 at 25°C under pH of 6.03. Adsorption of phosphate by Fe–Mn–La tri-metal composite adsorbent fitted better by pseudo-second-order kinetic equation and Langmuir model, which suggested that the adsorption process was surface chemical reactions and mainly in a monolayer coverage manner. The thermodynamic study indicated that the adsorption reaction was an endothermic process. The phosphate removal gradually decreased with the increasing of pH from 3.02 to 11.00. The sequence of coexisting anions competing with phosphates was that CO32− > Cl− > SO42− > NO3−. Dissolved organic matter, fulvic acid as a representative, would also decrease adsorption capacities of phosphate by Fe–Mn–La tri-metal composite adsorbents. Adsorption capacity would be decreased with increasing addition of adsorbents, while removal efficiency would be increased in this process. The Fe–Mn–La tri-metal composite adsorbent showed a good reusability when applied to removal of dissolved phosphate from aqueous solutions. The Fourier transform infrared spectrometer and X-ray photoelectron spectroscopy analyses indicated that some hydroxyl groups (–OH) on the surface of adsorbent were replaced by the adsorbed PO43−, HPO42−, or H2PO4−. Aggregative results showed that the novel Fe–Mn–La tri-mental composite sorbent is a very promising adsorbent for the removal of phosphate from aqueous solutions.

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Amino-Functionalized Multi-Walled Carbon Nanotubes as Novel Adsorbents for Selective Adsorption of Anionic Dyes in Aqueous Solution

NANO ◽

10.1142/s1793292015500654 ◽

2015 ◽

Vol 10 (05) ◽

pp. 1550065 ◽

Cited By ~ 3

Author(s):

Hui Huang ◽

Jingang Yu ◽

Wei Liu ◽

Xinyu Jiang

Keyword(s):

Carbon Nanotubes ◽

Aqueous Solution ◽

Adsorption Kinetics ◽

Organic Dyes ◽

Selective Adsorption ◽

Order Kinetic ◽

Equilibrium Isotherms ◽

Anionic Dyes ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

In this study, amino-functionalized multi-walled carbon nanotubes ( MWCNTs - NH 2) were successfully synthesized via an improved method and used for removal of organic dyes in aqueous solution. The synthesized MWCNTs - NH 2 were characterized by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscope (SEM), etc. The adsorption capacity and selectivity of MWCNTs - NH 2 for organic dyes was evaluated using rhodamine B ( RhB ), malachite green (MG), methyl orange (MO) and congo red (CR) as models. The selective adsorption toward anionic dyes was found for the MWCNTs - NH 2, and MO was selected as a typical anionic dye to deeply investigate the adsorption kinetics, equilibrium isotherms and thermodynamic parameters of the adsorption process. The adsorption kinetics and equilibrium isotherms data fitted well with the pseudo-second-order kinetic equation and Langmuir isotherm model. The thermodynamics study revealed that the adsorption of MO onto MWCNTs - NH 2 was spontaneous, exothermic and physisorptive in nature. The results indicated that MWCNTs - NH 2 are promising nanomaterials for removal of anionic dyes from industrial wastewater.

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Selective Adsorption of Aqueous Diclofenac Sodium, Naproxen Sodium and iBuprofen Using a Stable Fe3O4-FeBTC Metal Organic Framework

10.20944/preprints202102.0399.v1 ◽

2021 ◽

Author(s):

Aldo A. Castañeda Ramírez ◽

Elizabeth Rojas García ◽

Ricardo López Medina ◽

José L. Contreras Larios ◽

Raúl Suarez Parra ◽

...

Keyword(s):

Adsorption Capacity ◽

Magnetite Nanoparticles ◽

Naproxen Sodium ◽

Selective Adsorption ◽

Metal Organic Framework ◽

Diclofenac Sodium ◽

Aqueous Media ◽

Vital Role ◽

Maximum Adsorption Capacity ◽

Order Kinetic

Abstract: This work is part of the interest of solving the problems of water contamination with last generation pollutants, for which a novel and in an aqueous medium FeBTC material incorporated with magnetite nanoparticles was proposed. That material was synthesized by in situ solvothermal method, the Fe3O4 nanoparticles were added during the Fe-BTC MOF synthesis and used in the drug’s adsorption. The materials were characterized by XRD, FTIR and Raman spectroscopy, and N2-physisorption at 77 K. Fe3O4-FeBTC material showed a maximum adsorption capacity of 357.1 mg g−1 for diclofenac sodium, 70.9 mg g−1 for naproxen sodium, and 122.9 mg g−1 for Ibuprofen. A pseudo-second-order kinetic model can describe the adsorption process, and the thermodynamic study revealed that the adsorption of the three drugs was a feasible, spontaneous, and exothermic process. The incorporation of magnetite nanoparticles in the FeBTC considerably increased the adsorption capacity of pristine FeBTC. Also, hybridization of the FeBTC with magnetite nanoparticles reinforced the most vulnerable part of the MOF, increasing its thermal and aqueous media stability. The electrostatic interaction, H-bonding, and interactions in the open-metal sites played a vital role in drug adsorption. The competition of sites in the multicomponent mixture's adsorption showed selective adsorption at diclofenac sodium and naproxen sodium.

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Porous Multifunctional Phenylcarbamoylated-β-Cyclodextrin Polymers for Rapid Removal of Organic Pollutants

10.21203/rs.3.rs-571100/v1 ◽

2021 ◽

Author(s):

He Wang ◽

Congzhi Liu ◽

Xiaofei Ma ◽

Yong Wang

Keyword(s):

Organic Contaminants ◽

Adsorption Process ◽

Removal Rate ◽

Pollutant Removal ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Monolayer Adsorption ◽

Pseudo Second Order ◽

Rapid Removal ◽

Cyclodextrin Polymers

Abstract In this work, a series of porous multifunctional cyclodextrin (CD) polymers were fabricated using tetrafluoroterephthalonitrile (TFTPN) as the rigid crosslinker for the condensation of different functional phenylcarbamoylated-β-cyclodextrin derivatives to afford three preliminary polymerized adsorption materials such as poly nitrophenylcarbamoylated-β-cyclodextrin (NO2-CDP), poly trifluoromethylphenylcarbamoylated-β-cyclodextrin (F-CDP), poly chlorophenylcarbamoylated-β-cyclodextrin polymers (Cl-CDP) and a mix β- cyclodextrin polymer (X-CDP) prepared via a secondary crosslinking procedure of the above three materials. The X-CDP preparation process connects the `pre-formed nanoparticles and increases the presence of linkers inside the particles. At the same time, X-CDP exhibited porous structure with various functional groups such as nitro, chlorine, fluorine and hydroxyl. Those special characteristics render this material with good adsorption ability towards various pollutants in water, including tetracycline, ibuprofen, dichlorophenol, norfloxacin, bisphenol A, naphthol. Especially the maximum adsorption capacity for tetracycline at equilibrium reached 230.15 mg·g− 1, which is competitive with the adsorption capacities of other polysaccharides adsorbents. X-CDP removed organic contaminants much more quickly than other adsorbents, reaching almost ~ 95% of its equilibrium in only 30 s. The main adsorption process of the pollutants by X-CDP fitted the pseudo-second-order kinetic and Langmuir isotherm well, indicating that the adsorption process is monolayer adsorption. Moreover, X-CDP possessed the good reusability where the pollutant removal rate was only reduced 8.3% after five cycles.

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Preparation of TiO2-Poly(3-Chloro-2-Hydroxypropyl Methacrylate) Nanocomposite for Selective Adsorption and Degradation of Dyes

Technologies ◽

10.3390/technologies6040092 ◽

2018 ◽

Vol 6 (4) ◽

pp. 92 ◽

Cited By ~ 4

Author(s):

M. Hossan ◽

Bungo Ochiai

Keyword(s):

Uv Irradiation ◽

Selective Adsorption ◽

Industrial Effluents ◽

Cationic Dyes ◽

Adsorption Efficiency ◽

Anionic Dyes ◽

Propyl Methacrylate ◽

Accelerated Degradation ◽

Hydroxypropyl Methacrylate ◽

Degradation Of Dyes

We report a new nanocomposite TiO2-poly(3-chloro-2-hydroxypropyl methacrylate) (TiO2-PCHPMA) for selective adsorption/degradation of cationic dyes and degradation of anionic dyes. TiO2-PCHPMA was prepared by free radical polymerization of CHPMA in the presence of TiO2 modified with 3-(trimethoxysilyl)propyl methacrylate. TiO2-PCHPMA adsorbed cationic methylene blue (MB), but did not adsorb anionic methyl orange (MO) in their aqueous solutions. The adsorption efficiency for MB reached 99% within 5 min at 28 °C, and adsorbed MB could be recycled in 96% efficiency. The adsorption accelerated degradation of MB under UV irradiation. The degradation of anionic MO proceeded completely with TiO2-PCHPMA under UV irradiation, and the efficiency was not affected by the PCHPMA layer. TiO2-PCHPMA is potentially applicable as a material capable of selective removal and recovery of cationic dyes, and degradation of other dyes from industrial effluents.

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Continuous Flow Removal of Anionic Dyes in Water by Chitosan-Functionalized Iron Oxide Nanoparticles Incorporated in a Dextran Gel Column

Nanomaterials ◽

10.3390/nano9081164 ◽

2019 ◽

Vol 9 (8) ◽

pp. 1164 ◽

Cited By ~ 3

Author(s):

Sang Yeob Lee ◽

Ha Eun Shim ◽

Jung Eun Yang ◽

Yong Jun Choi ◽

Jongho Jeon

Keyword(s):

Removal Efficiency ◽

Continuous Flow ◽

Aqueous Media ◽

Dye Adsorption ◽

Current Method ◽

Maximum Adsorption Capacity ◽

Anionic Dyes ◽

Solution Ph ◽

Adsorbent Surface ◽

Equilibrium Data

This paper describes a novel chromatographic method for efficient removal of anionic dyes from aqueous solutions. Chitosan-coated Fe3O4 nanoparticles can easily be immobilized on a dextran gel column. Single elution of Evans Blue (EB) solution to the nanoadsorbent-incorporated columns provides high removal efficiency with a maximum adsorption capacity of 243.9 mg/g. We also investigated the influence of initial concentration and solution pH on the removal efficiency of EB. The electrostatic interaction between the adsorbent surface and negatively charged sulfate groups on EB molecules promotes the efficient adsorption of dyes. The equilibrium data matched well with the Langmuir isotherm model, which indicated monolayer dye adsorption onto the adsorbent surface. To extend the application of the current method, we performed further adsorption experiments using other anionic dyes of different colors (Cy5.5, Acid Yellow 25, Acid Green 25, and Acid Red 1). All of these molecules can efficiently be captured under continuous flow conditions, with higher removal efficiency obtained with more negatively charged dyes. These findings clearly demonstrate that the present approach is a useful method for the removal of anionic dye contaminants in aqueous media by adsorption.

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The Adsorption of Methylene Blue by an Amphiphilic Block Co-Poly(Arylene Ether Nitrile) Microsphere-Based Adsorbent: Kinetic, Isotherm, Thermodynamic and Mechanistic Studies

Nanomaterials ◽

10.3390/nano9101356 ◽

2019 ◽

Vol 9 (10) ◽

pp. 1356 ◽

Cited By ~ 6

Author(s):

Xuefei Zhou ◽

Mingzhen Xu ◽

Lingling Wang ◽

Xiaobo Liu

Keyword(s):

Methylene Blue ◽

Adsorption Process ◽

Selective Adsorption ◽

Modern Society ◽

Influential Factors ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Cationic Dye ◽

Solution Ph ◽

Arylene Ether

Dye pollution is a serious problem in modern society. We desired to develop an efficient adsorbent for the decontamination of discharged dyes. In this work, the polymeric microspheres derived from a kind of amphiphilic block of co-poly(arylene ether nitrile) (B-b-S-P) were prepared on the basis of “oil-in-water” (O/W) microemulsion method. The B-b-S-P microspheres were found competent to remove the cationic dye, methylene blue (MB); and various influential factors, such as contact time, initial concentration, solution pH and temperature were investigated. Results indicated that the maximum adsorption capacity of B-b-S-P microspheres for MB was 119.84 mg/g at 25 °C in neutral conditions. Adsorption kinetics and isotherm dates were well fitted to a pseudo-second-order kinetic model and the Langmuir isotherm model, and thermodynamic parameters implied that the adsorption process was endothermic. The B-b-S-P microspheres also exhibited a highly selective adsorption for cationic dye MB, even in the presence of anionic dye methyl orange (MO). In addition, the possible adsorption mechanism was studied, suggesting that the electrostatic interaction and π–π interaction could be the main force in the adsorption process.

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Fabrication of Diatomite/Silicalite-1 Composites and Their Property for VOCs Adsorption

Materials ◽

10.3390/ma12040551 ◽

2019 ◽

Vol 12 (4) ◽

pp. 551 ◽

Cited By ~ 9

Author(s):

Yutong Liu ◽

Tao Tian

Keyword(s):

Volatile Organic Compounds ◽

Ethyl Acetate ◽

Adsorption Capacity ◽

Organic Compounds ◽

Hydrothermal Reaction ◽

Selective Adsorption ◽

Maximum Adsorption Capacity ◽

Voc Adsorption ◽

Hierarchical Porous ◽

Volatile Organic

Adsorption technology is an effective method to remove volatile organic compounds (VOCs). In this work, we prepared hierarchical porous materials using modified diatomite (Dt) as a support and nano-sized silicalite-1 (S-1) seeds as inorganic fillers, which were applied to adsorb volatile organic compounds (VOCs). The characterization of the composites indicated that S-1 was successfully coated onto the surface of modified Dt, and the best surface area of the composites was 398.8 m2/g, nearly 40 times as large as Dt. The adsorption capacities of Dt/S-1 composites for three probe VOCs (ethyl acetate, acetone, and toluene) were rather superior to Dt, and the composites had preferential adsorption selectivity for ethyl acetate. Effects of seeded zeolite contents and hydrothermal conditions for the adsorption capacity of composites were discussed in this paper. The composite seeded with 5 wt% S-1 zeolite, which was subsequently synthesized by hydrothermal reaction at 100 °C for four days, showed the maximum adsorption capacity (1.31 mmol/g for ethyl acetate). The pseudo second-order model provided a perfect fit to adsorption kinetics, while the Langmuir model agreed the best with the adsorption isotherms. In addition, the composites had selective adsorption to ethyl acetate among these three probes VOCs. The regeneration experiments were also carried out, and the adsorption efficiency of the adsorbents was still up to 67% after five adsorption–desorption cycles. The hierarchical porous Dt/S-1 composites have an excellent VOC adsorption performance, satisfactory selectivity, and recycling ability.

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