SO3Na Groups Research Articles

Efficient Solid-Phase Extraction of Neonicotinoid Insecticides from Environmental Water and Drink Samples Using a Postmodified Metal-Organic Framework.

Neonicotinoid insecticides (NNIs) are extensively utilized globally because of their efficient and broad-spectrum properties. However, their residues are also extensively distributed in the environment. Herein, MIL-101-SO3Na with abundant -NH- and sulfonate groups was synthesized via chloromethylation and nucleophilic substitution postmodification strategies and used to extract NNIs via solid-phase extraction. MIL-101-SO3Na was enhanced by introducing C-H···N hydrogen bonds to strengthen interaction forces and -SO3Na groups to adjust surface charge and enhance electrostatic attraction. This modification and the substantial specific surface area (998 m2·g-1) of the metal-organic framework markedly enhanced the enrichment efficiency of MIL-101. The proposed method based on MIL-101-SO3Na exhibited a minimal detection threshold (0.04-0.87 ng·L-1), an extensive linear spectrum (1-2000 ng·L-1), and notable accuracy (a variation of 3.02-11.8%) in water and drink samples. NNI concentrations between 0.25 and 24.2 ng·L-1 in fruit juice and tea samples were accurately identified using the proposed method, demonstrating its feasibility in practical applications. The postmodification of MIL-101-SO3Na is an exceptional and promising approach for the sensitive detection of ultratrace NNI levels in complex matrices.

Synthesis of nano zero valent zinc-reduced graphene oxide nanocomposite using a novel electrochemical technique for the adsorptive degradation of methyl orange

Indiscriminate disposal of effluent contaminated with persistent azo dyes has become a significant environmental issue. Since the conventional wastewater treatment processes are ineffective in removing azo dyes completely, many studies are currently being focused on finding effective methods to degrade azo dyes. We herein report a novel in-situ synthesis of a nanocomposite with nano-zero valent zinc (nZVZ) and reduced graphene oxide (rGO) that can effectively remove methyl orange, an azo dye, from an aqueous solution via adsorptive degradation. nZVZ-rGO nanocomposite was synthesized by electrochemical reduction of Zn2+ ions on rGO. The presence of nZVZ particles on rGO with an average metal-loading of 4 % was confirmed by SEM-EDS, TEM, XPS and XRD results. Batch experiments showed that a maximum removal efficiency of 99.6 % of methyl orange can be achieved with 25 mg L−1 initial dye concentration and by optimizing the pH, nanocomposite dosage and contact time. However, a noticeable reduction in removal efficiency was observed in the presence of anions such as Cl-, SO42- and CO32-. The degradation of methyl orange was monitored using UV-Visible spectroscopy, HPLC and FTIR spectroscopy. The peaks corresponding to -NN- group, –C-N bond and –SO3Na group have completely disappeared in the product spectrum of FTIR analysis, indicating the degradation of methyl orange. The adsorptive degradation process of methyl orange obeys the Sips model (R2=0.9820) indicating a complex heterogenous adsorption mechanism while the kinetic model was shown to be pseudo-second-order model (R2=0.9999).

A novel modified carboxymethyl cellulose hydrogel adsorbent for efficient removal of poisonous metals from wastewater: Performance and mechanism

A cost-efficient and simple method, grafting sodium sulfonate groups (−SO3Na) onto carboxymethyl cellulose (CMC), was developed to form hydrogel adsorbents for the removal of poisonous metals including Cu(Ⅱ) and Zn(Ⅱ) from wastewater. In this work, cellulose-based hydrogels (CMC-g-P(AA-co-SS)) were prepared using acrylic acid (AA) and sodium styrene sulfonate (SS). FTIR, XPS, SEM, and EDX were employed to analyze the surface morphology and structure of CMC-g-P(AA-co-SS). The results revealed that the synergistic effect of −SO3Na and carboxylate groups (−COO−) facilitated the adsorption of heavy metals. Moreover, introducing AA and SS enhanced the swelling degree of CMC hydrogels. The results of adsorption experiments showed that high adsorption efficiencies were obtained for Cu(Ⅱ) and Zn(Ⅱ) (200.44 mg/g and 192.28 mg/g, respectively) within 180 min. The adsorption isotherm and kinetics indicated that the monolayer chemical adsorption dominated the process. After 5 cycles, the adsorption activity of CMC-g-P(AA-co-SS) remained high, with the adsorption capacity for Cu(Ⅱ) and Zn(Ⅱ) being 93.3% and 78.3% of the original, respectively. Thus, the CMC-g-P(AA-co-SS) is a promising adsorbent candidate for the removal of poisonous metals from wastewater.

Highly crystalline ionic covalent organic framework membrane for nanofiltration and charge-controlled organic pollutants removal

Organic pollutants are biological toxicity and should be removed from the environment. Membrane separation offers several advantages in organic pollutants removal such as high pollutants selectivity and high solvent permeability. Covalent organic framework membrane is regarded as an emerging porous membrane for nanofiltration owing to their permanent porosity and well-defined pore structure in various organic media. Herein, a self-standing 2D sulfonate anionic COF membrane with nanometer pore size and -SO3Na groups has been successfully prepared. The surface charge combines with nanopore sieving property endow the COF membrane high nanofiltration separation performances and charge-controlled organic molecular separation. The anionic membrane can effectively intercept > 99% of cationic organic pollutants, while maintaining excellent solvent permeability due to its rigid porous structure and high porosity. The density functional theory (DFT) calculation provides further understanding on the charge-controlled separation in ionic nanoporous membranes. Our work may open up a new avenue for developing charged COF membrane for nanofiltration and organic pollutants separation applications.

Design and fabrication of a novel humidity sensor based on ionic covalent organic framework

With the increasing requirement of precise humidity control in agriculture, industry, and scientific experiments, the humidity sensors based on porous materials such as metal-organic framework (MOF) have aroused much attention because of their high porosity and tunable structure. However, the reported MOFs exhibit narrow detecting range and long response time due to the absence of ion carriers in porous framework. In this paper, an ionic covalent organic framework (COF) named TpPa-SO3Na was synthesized, and its humidity sensing performance was investigated for the first time. TpPa-SO3Na with -SO3Na groups possesses a water adsorption capacity of 411 cm3 g−1, which is confirmed by water adsorption-desorption measurement. The sensor based on TpPa-SO3Na exhibits good impedance-RH linearity, rapid response characteristic (∼6 s) and narrow hysteresis (∼3% RH) in the 11–95 % RH. Moreover, the ionic COF sensing material presents good repeatability. These results strongly suggest ionic COFs are a class of promising candidates for humidity sensing applications.

Design, synthesis, and biological activity of Schiff bases bearing salicyl and 7-hydroxycoumarinyl moieties

18 (11 novel) Schiff bases, derivatives of salicylaldehyde, 2-hydroxyacetophenone, and 6-acetyl-, 8-acetyl-, and 8-formyl-7-hydroxy-4-methylcoumarin were synthesized and characterized by their spectral studies. 6-Acetyl-7-hydroxy-4-methylcoumarin was prepared by novel method under microwave assistance. These Schiff bases were evaluated for antibacterial activities against 12 bacterial and six fungi strains in vitro. N-(3,5-Dichloro-2-hydroxybenzylidene)-4-aminobenzenesulfonic acid sodium salt proved to be the most active against Staphylococcus aureus and MRSA strains (MIC 0.0194 µmol/cm3). The substitution pattern, two chlorine atoms in the salicylidene ring and the SO3Na group, is probably the most beneficial for the activity against Gram-(+) bacteria strains. All Schiff bases were evaluated for cancer efficacy against CFPAC-1 and HeLa cell cultures originating from human pancreas cancer or human cervical cancer. Schiff bases derived from salicylaldehyde are highly effective in pancreas and cervical cancer cells; however, they demonstrate also substantial toxicity towards NIH3T3 cells. Derivatives of coumarin contain three highly selective compounds: 7-hydroxy-8-[(4-methoxyphenylimino)methyl]-4-methyl-2H-chromen-2-one, N-[(7-hydroxy-4-methyl-2-oxo-2H-chromen-8-yl)methylene]-4-aminobenzenesulfonic acid sodium salt, and 7-hydroxy-8-[1-(4-hydroxyphenylimino)ethyl]-4-methyl-2H-chromen-2-one suggesting more promising potential of the second group of substances.Graphical abstract

Radiation synthesis and characterization of super-absorbing hydrogel from natural polymers and vinyl monomer

This article exploits a new approach for synthesis of polysaccharide-based grafted sodium styrene sulfonate (SSS) super absorbent hydrogels (SAHs) in aqueous solution by γ-radiation under ambient conditions. Important optimal conditions for preparation of hydrogels with the best swelling ratio, such as gamma irradiation dose and the ratio of feed composition have been discussed. Characterization techniques such as the SEM/EDS, FTIR and DSC were used in describing the newly prepared hydrogels. The FTIR gave characteristic peaks for -SO3Na group at 1042 and 988 cm−1, showing successful grafting of SSS onto the polysaccharide base material. The dependence of swelling behaviors in various pH solutions and salts solutions were investigated in detail. The prepared hybrid hydrogel showed most optimum swelling capacity at neutral pH whereas equilibrium swelling of SAHs was achieved within 5 h. The swelling of SAHs influenced obviously to metal ion removal percentage in solution.

Spectroscopic Characterization of Azo Dyes Aggregation Induced by DABCO-Based Ionene Polymers and Dye Removal Efficiency as a Function of Ionene Structure.

The aggregation mode of three azo dyes, methyl orange (MO), ponceau SS (PSS), and direct blue 1 (DB1) induced by three 1,4-diazabicyclo[2.2.2]octane (DABCO)-based ionene polymers having different topologies (i.e., 1,2-ionene, 1,3-ionene, and 1,4-ionene) was investigated in this work. Metachromatic behavior of the dyes in the presence of ionenes, and the stability of the ionene/dye complex were discussed as a function of ionene structure. It was demonstrated that the association of the dye molecules with the ionenes and the metachromasy were strongly influenced by both the dye structure and the ionene topology. Thus, MO, having one -SO3Na group per molecule, was almost stoichiometrically bound to all ionenes regardless of their topology, showing also a metachromatic effect. In sharp contrast, the interaction of PSS and DB1 molecules with ionenes was strongly dependent on the polymer topology. It was found that PSS having two -SO3Na groups per molecule was preferentially bound onto both 1,2-ionene and 1,3-ionene, but DB1, having four -SO3Na groups per molecule and a more complex structure, was efficiently bound only onto 1,2-ionene. The dye removal efficiency with each ionene was evaluated in batch mode taking into account the affinity of ionenes for azo dyes. The experimental isotherms of the dye sorption were fitted with four isotherm models, i.e., Langmuir, Freundlich, Sips, and Dubinin-Radushkevich. It was found that the best fitting of the experimental data was given by the Langmuir, Sips, and Dubinin-Radushkevich isotherm models. The maximum equilibrium sorption capacity, qm, evaluated by the Langmuir model, at 35 °C, was as follows: 985.71 mg MO/g 1,3-ionene, 483.71 mg PSS/g 1,3-ionene, 1010.49 mg PSS/g 1,2-ionene, and 976.7 mg DB1/g 1,2-ionene. Kinetic study of the dye removal indicated chemisorption as the main mechanism of sorption.

Removal of metal ions from aqueous solutions using carboxymethyl cellulose/sodium styrene sulfonate gels prepared by radiation grafting

Sodium Carboxymethyl Cellulose (CMCNa)/Sodium Styrene Sulfonate (SSS) hydrogels with grafted and crosslinked polymeric networks were prepared by γ-radiation at atmosphere condition. The obtained hydrogels were characterized by gel fraction, swelling ratio, TGA and FTIR spectroscopy. The results showed the ratio of CMC and SSS 1:0 gave the highest gel fraction, compared with other ratios. The swelling capacity increased by increasing SSS content due to the presence of SO3Na, OH groups in gel structure. The FTIR spectrum of CMC/SSS gel showed the new absorption peaks at 1034 and 1012cm−1 corresponds to SO3Na group. The metal ion adsorption capacity of CMC/SSS gel was investigated. The grafted gel effectively removed metal ions, especially Cr and Pb. The effects of hydrogel composition, contact time, and initial concentration on the adsorption capacity of the grafted hydrogels were studied. The adsorption kinetics and equilibrium isotherms were investigated using pseudo-second-order model and Langmuir model.

Accelerated Sorption Diffusion for Cu(II) Retention by Anchorage of Nano-zirconium Dioxide onto Highly charged Polystyrene Material.

The development of nanocomposite with strong adsorption ability exhibits great potential applications for environmental remediation. However, the pore blocking in preparation frequently constrains sorption diffusion, resulting in low utilization efficiency. Here we synthesized a new nano-ZrO2/Polystyrene (NZO-PS) material tailored with a specific fixed SO3-Na group to enhance Cu(II) removal. The NZO-PS exhibits efficient Cu(II) sequestration in a wide pH range (3.0–6.5) and preferential sorption performances. The efficient kinetic behavior and column applicability suggest the blocked pore channel is not a matter when presence of negatively charged moiety, which accelerates Cu(II) sorption diffusion and enrichment toward target active site. Moreover, the exhausted NZO-PS can be readily regenerated through HCl-NaCl binary solution. The preparation route can be extended to synthesize other functional composited materials. Simultaneously, the characteristics of simplicity, high-yield and regeneration provide some promising industrial merits.

A new method for the synthesis of monodisperse-porous titania microbeads by using polymethacrylate microbeads as template

Monodisperse-porous titania microbeads were synthesized by sol–gel templating method by using a new type of polymethacrylate microbeads as template. Monodisperse-porous poly(3-chloro-2-hydroxypropyl methacrylate-co-ethylene dimethacrylate), poly(HPMA-Cl-co-EDMA) microbeads 5.4 μm in size were used as starting material for the preparation of new template. Strong cation exchanger –SO3Na groups were generated on the selected polymethacrylate template via the reaction between chloropropyl groups of template and sodium bisulfite. –SO3Na functionalized-polymethacrylate microbeads were treated with the precursor, TiCl4 in an aqueous medium and subsequently treated with ammonia to obtain titania-polymer composite microbeads. The composite microbeads were then calcined at 450 °C to have monodisperse-porous titania microbeads. Monodisperse-porous titania microbeads in the size range of 3.0–5.0 μm with crater-like or fine porous structures with specific surface areas ranging between 50 and 91 m2/g were obtained by changing the concentration, crosslinking density of the template beads and the calcination temperature. The selection of a polymethacrylate template decomposed at lower temperatures with respect to poly(styrene-co-divinylbenzene) type templates, commonly used for synthesis of porous titania microbeads, allowed to perform the calcination of titania-polymer composite microbeads at lower temperatures. Monodisperse-porous titania microbeads with higher specific surface area and a crystalline structure with higher percent of anatase phase could be obtained by performing calcination at lower temperatures. The photocatalytic activity of monodisperse-porous titania microbeads was investigated using an anionic azo-dye, Remazol Black 5 (RB5) in batch-fashion. Higher photodegradation rates were observed with the monodisperse-porous titania microbeads in the acidic pH region compared to TiO2 nanoparticles.

A sulfonated polyaniline with high density and high rate Na-storage performances as a flexible organic cathode for sodium ion batteries.

A Na-rich cathode is developed by grafting the electron-withdrawing -SO3Na group on polyaniline chains. Due to the immobile doping and effective activation of the sulfonate group, this polymer demonstrates a high capacity (133 mA h g(-1)) and excellent cyclability through a cation-exchange reaction, offering a low cost and sustainable cathode for SIBs.

The effects of multi-functional groups from PVA and ternary multisilicon copolymer on diffusion dialysis

Ternary multisilicon copolymers are prepared from copolymerization of acrylic acid, sodium styrene sulfonate and γ-methacryloxypropyl trimethoxy silane, from which functional groups of –Si(OCH3)3, –COOH and –SO3Na are obtained respectively. The acidic –COOH groups may induce gel during copolymerization, and thus sufficient solvent needs to be used. The –Si(OCH3)3 groups can crosslink with polyvinyl alcohol (PVA) to yield cation exchange hybrid membranes.The membranes have the ion exchange capacity of 1.01–2.26mmol/g, water uptake of 39.1–59.7%, swelling degrees of 108–339% in 65°C water after 192h, and swelling degrees of 254–344% in 65°C alkaline solution after 60h. Membrane with proper ratios of multi-functional groups can sorb 1.4mol/L NaOH in 1.0mol/L NaOH solution. The membranes are used in diffusion dialysis (DD) process for alkali recovery from NaOH/Na2WO4 solution. The dialysis coefficients of NaOH (UOH) are in the range of 0.013–0.021m/h at room temperature, with the separation factors of 15–23. The high UOH values indicate the superiority of multi-functional groups. The –OH, –COOH and –SO3Na groups from PVA and multisilicon copolymer chains may have coupling effects on the transport of both Na+ and OH− ions.

Polyelectrolyte complex/PVA membranes for diffusion dialysis

Polyelectrolyte complexes (PECs)/polyvinyl alcohol (PVA) membranes are prepared from PVA, anion exchange and cation exchange multisilicon copolymers, which contain plenty of functional groups of OH, N+(CH3)3/Si(OCH3)3, and SO3Na/Si(OCH3)3, respectively. The OH and Si(OCH3)3 groups can undertake sol–gel reaction to form crosslinking structure, while the N+(CH3)3 and SO3Na groups can be combined through electrostatic interaction.The PECs/PVA membranes exhibit improved thermal stability, swelling resistance and flexibility as compared with single anion or cation exchange hybrid membranes. The PECs/PVA membranes have the water uptakes (WR) of 25.3–70.4%, initial decomposition temperatures (IDTs) of 246–285°C, tensile strength of 23.1–33.8MPa, and elongation at break of 3.5–13.1%. The membranes can be potentially applied for both acid and alkali recovery through diffusion dialysis (DD) process. The separation factor (S) for HCl/FeCl2 mixture can reach up to 89.9, which is about five times higher than that of commercial DF-120 membrane (18.5 at 25°C). The dialysis coefficients of NaOH (UOH) are in the range of 0.014–0.019m/h, around 7–9 times higher than the value of commercial SPPO membrane (0.002m/h at 25°C). The membranes also show potential usefulness for industrial acidic and alkali wastes treatment.

Synthesis and characteristics of UV curable dimethyl 5-sulfoisophthalate sodium salt-co-diethylene glycol with maleic and phthalic anhydride copolymers (DMSIP-co-DEG-co-MA/PA) for application in redox flow batteries

Dimethyl 5-sulfoisophthalate sodium salt (DMSIP)-co-diethylene glycol (DEG)-co-maleic anhydride (MA)/phthalic anhydride (PA) oligomers were synthesized via condensation reaction and the corresponding membranes were prepared by UV curing. The number-average molecular weight (Mn) of the DMSIP-co-DEG-co-MA/PA (DDMP) was proportional to the concentration of DMSIP and ranged from 1,360–2,856 g/mol. A successful introduction of a -SO3Na group to the main oligomer chain was confirmed using Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy and the thermal stability of the membranes up to 300 °C was analyzed using thermogravimetric analysis (TGA). The water uptake values, swelling ratios, and the ion-exchange capacities of the membranes were 13%–30%, 7%–15%, and 0.7–0.9 meq/g, respectively. The electrical properties of the membrane, including the area resistance, ion transport number, and the cyclic charge-discharge current were also analyzed; these properties confirmed that these membranes were suitable for use in redox flow battery (RFB) applications. Open image in new window

Preparation of dibromopyridines having –(CH2)m–SO3Na groups as monomers for new polypyridines

Dibromopyridines or dibromopyridone with –(CH2)m–SO3Na group(s) has been prepared via the reactions of the corresponding dibromopyridines with –OH and –NH2 groups with sultone. These compounds were converted into polymers with the –(CH2)m–SO3H groups via organometallic polycondensation. The polymer showed proton conducting properties and high stability toward oxidation.

PVA-based hybrid membranes from cation exchange multisilicon copolymer for alkali recovery

Cation exchange multisilicon copolymers i.e. copolymers containing pendent siloxane and SO3Na groups are developed from the copolymerization of sodium styrene sulfonate (SSS) and γ-methacryloxypropyl trimethoxy silane (γ-MPS). The copolymerization process can proceed smoothly without formation of gel. The copolymers are compatible with water, and can produce transparent and homogeneous solutions when mixed with poly(vinyl alcohol) (PVA), so that transparent and compact hybrid membranes are obtained.The membranes are thermally and mechanically stable, with initial decomposition temperatures of 237–273°C, tensile strength of 9.1–26.0MPa and elongation at break of 12.4–21.1%. The membranes have a water uptake (WR) of 30.0–54.8% and swelling degrees of 46–115% in 65°C water, which are mainly controlled by the content of Si(OCH3)3 groups in the mutlisilicon copolymers. Diffusion dialysis (DD) separation of NaOH/Na2WO4 solution indicates that the alkali dialysis coefficients (UOH) are in the range of 0.010–0.011m/h, higher than the values of commercial membrane (0.00137m/h) and other polymer based hybrid membranes (0.0014–0.0022m/h). The membrane structure and properties are correlated with the ions transport mechanism, revealing interesting findings as to the influence of IEC and different functional groups on DD behavior.

Effects of ethanol and isopropanol on the structures and properties of polyethersulfone/perfluorosulfonic acid nanofibers fabricated via electrospinning

Blend solutions of polyethersulfone (PES) and perfluorosulfonic acid (PFSA) resin were fabricated into nanofibers via electrospinning. Ethanol (EtOH) and isopropanol (IPA) were employed to investigate the effects of non-solvent (NS) on the structures and properties of the electrospun PES/PFSA nanofibers. Average diameters of the electrospun nanofibers increased with NS content while the water contact angles of the nanofiber membranes decreased. Although all the nanofiber membranes presented strong hydrophobicity initially, the water contact angle would drop to less than 90° within 30 min. Energy dispersive X-ray spectrums (EDS) showed that the nanofibers electrospun from solutions with more NS presented higher sodium content on the surface because more -SO3Na groups were on the external plane. N2 adsorption-desorption measurement revealed that increase of NS content in the solvent mixtures resulted in nanofibers with surface area much bigger in experiment than that in calculation, which meant rough structures occurred on the surface of electrospun nanofibers. These rough structures were beneficial to improve the frictional resistance between nanofibers and therefore enhanced the break strength and Young’s modulus of the nanofiber membranes.

Cation-Exchange Membranes Prepared by Pre-Irradiation Grafting of Acrylic Acid and Sodium Styrene Sulfonate onto ETFE Membranes

Poly (ethylene-co-tetrafluoroethylene) (ETFE) membranes were irradiated by electron beams and then acrylic acid (AA) and sodium styrene sulfonate (SSS) were grafted onto the membranes, in an attempt to prepare cation exchange membranes containing -COOH and -SO3Na groups. The grafting yield was found to be strongly dependent on the synthesis condition such as irradiation dose, co-monomer composition. Infrared spectroscopy of the grafted membrane confirmed the existence of sulfonate and carboxylic acid groups. The membrane resistance decreases with the increasing of grafting yield

Synthesis and properties of side-chain-type ion exchange membrane PEEK-g-StSO3Na for bipolar membranes

Side-chain-type ion exchange membranes (PEEK-g-StSO3Na) were prepared by grafting poly (ether ether ketone) (PEEK) containing propenyl groups with sodium sulfonic styrene (StSO3Na) and KH570. PEEK was synthesized by the aromatic nucleophilic polycondensation reaction of 4,4′-difluorobenzophenone, bisphenol A and diallylbisphenol A. The synthesized copolymers with the –SO3Na group on the side chain of polymers possessed high molecular weights. The cross-linking reaction was carried out through a sol–gel reaction of the trimethoxysilane group. The copolymer membranes exhibited excellent mechanical properties due to their aromatic structure extending through the backbone and flexible StSO3Na aliphatic chains. The ion exchange capacities (IECs) of the membranes ranged from 2.27 to 2.50mmolg−1 and the water content ranged from 107.2 to 126.1%, with both parameters increasing with StSO3Na grafting degree. The H+ permeability of copolymer membranes increased with increasing IEC, reaching value above 0.3056mol/L at 2h, which is higher than that of Nafion® 117 at the same measurement condition. They displayed reasonably high H+ permeability due to the higher acidity of benzoyl sulfonic acid group, the larger interchain spacing, which is available for water occupation, and the lower AC impedance of the bipolar membrane.