Addition Of Inorganic Salts Research Articles

Study on electrolyte additives of water-based magnesium batteries

The effects of different inorganic salt additives on the corrosion resistance, hysteretic behavior and activation potential of magnesium anode in MgSO4-Mg(NO3)2 composite electrolyte (1.86 mol·L-1 Mg(NO3)2 + 0.14 mol·L-1 MgSO4) were compared by electrochemical method. The electrochemical test results showed that in the solution containing 0.02 mol/L NaHCO3, the activation potential of magnesium anode was the most positive, the passivation range was expanded, and the polarization current was reduced. The impedance of magnesium alloy with 0.02 mol/L NaHCO3 has the highest corrosion resistance, which is consistent with the conclusion that the corrosion current density of Tafel polarization curve is the lowest. Under the additive concentration, the magnesium anode has the shortest lag time, the most negative discharge potential and the least potential drop, which greatly improve the discharge performance of magnesium anode.

Size, shape and surface structure of gold snowflake-like particles tailored by the addition of monovalent and divalent inorganic salts

Gold nanostructures are known for their unique electro-optical behavior called surface plasmon resonance. Their chemically stable and biocompatible properties are being utilized in a vast area of applications. Within this work, gold snowflake-like particles (Au SFLPs) were prepared via chemical reduction in an aqueous bulk phase assisted by monovalent and divalent inorganic salts. The addition of inorganic salts in combination with a particular concentration ratio between chemical reduction precursors plays a key role in the Au SFLPs size, surface morphology and shape evolution. The reaction parameters, such as reaction temperature, pH, stirring speed, concentrations of reactants and their types, influencing shape development of Au SFLPs, were systematically tested and described. The theory of growth and aggregation of gold seeds and the diffusion within the electric double layer – surrounding the particles, is used to propose a controlled mechanism, explaining the organization of gold atoms into Au SFLPs. A novel efficient trapping method was developed to efficiently collect individual Au SFLPs without surface structure destruction. Enhanced electro-optical behavior of the Au SFLPs, resulting from the nanostructured surface, was confirmed by the detection of 5,10,15,20-Tetrakis(1-methyl-4-pyridinio)porphyrin via surface-enhanced Raman spectroscopy (SERS).

Spray drying absorption for desulphurization: a review of recent developments

Sulphur dioxide (SO2) abatement technologies, i.e. flue gas desulphurization (FGD), have proven effective in curtailing the harmful SO2 emissions resulting from coal combustion for electrical power generation. New regulations on these emissions now require some power utilities to retrofit new FGD units to existing coal-fired power plants to meet required emission standards. Wet FGD limestone scrubbing has been predominantly used over other competing technologies. However, the simplicity of the spray-drying absorption (SDA) technology has made it an attractive alternative to the wet scrubbing process. SDA offers huge savings on energy, water, operating cost and maintenance. Despite high cost of the sorbent (hydrated lime) used, recent advances in SDA process offer considerable economic and technical advantages ranging from improved sorbent utilization, better atomization and enhanced performance. Alternative sorbents and additives are continuously being explored for simultaneous removal of pollutant gases from flue gas. The performance improvement areas in a lime spray drying system include the use of inorganic salt additives, recycling of the dried product and the use of siliceous materials. This study is intended to review FGD systems applicable to coal-fired power plants, through a technical comparison between competing technologies. Additionally, a review of the spray-drying absorption process and operating parameters affecting their efficiency was carried out, together with a critical assessment of the literature published to date.

Ionic Salt-Mediated Tuning of the Morphology and Band Structure of Graphitic Carbon Nitride for NO Removal under Visible Light

Graphitic carbon nitride (g-C3N4, CN) as a popular photocatalyst has been investigated for the removal of air pollutants, but its photocatalytic efficiency and selectivity for ionic species (Si) can be enhanced through chemical or microstructural modification. The combinatorial study of six salts, Na+, K+, and NH4+ (per)sulfate, as mediators in the melamine precursor for the CN synthesis indicates that the thermal decomposition behaviors of the salts affect the CN polymerization process and the functional groups on CN samples, though all of them are found to increase the surface area. The mediation with Na+ and K+ (per)sulfate increases the dangling −C≡N bonds and surface moieties at a higher oxidation state. The sodium and ammonia salts caused an upward shift of the conduction band energy for the final photocatalyst, while K2SO4 and K2S2O8 induced a downward shift of the conduction band. The NO removal efficiency of CN with sodium persulfate and sulfate reached 80% and near 100%, respectively, much higher than that of the pristine CN (60%). Moreover, the samples with persulfates showed higher Si than those with sulfate salts. The high surface area and the keen hierarchical pores down to 2 nm in the salt-mediated CN samples increased the residence time of the gaseous species and the resultant NO removal efficiency, and Si. NO2 can still be produced in the dark for 15 min after the photocatalysis, indicating that there are long-lived species related to H2O2 produced in the prior illumination. The systematic investigation of the effects of inorganic salt addition was presented on CN in terms of the microstructure, band structure, and correlated photocatalytic oxidation efficiency, pathway, and product selectivity.

Aqueous-phase behavior of glyoxal and methylglyoxal observed with carbon and oxygen K-edge X-ray absorption spectroscopy

Abstract. Glyoxal (CHOCHO) and methylglyoxal (CH3C(O)CHO) are well-known components of atmospheric particles and their properties can impact atmospheric chemistry and cloud formation. To get information on their hydration states in aqueous solutions and how they are affected by the addition of inorganic salts (sodium chloride (NaCl) and sodium sulfate (Na2SO4)), we applied carbon and oxygen K-edge X-ray absorption spectroscopy (XAS) in transmission mode. The recorded C K-edge spectra show that glyoxal is completely hydrated in the dilute aqueous solutions, in line with previous studies. For methylglyoxal, supported by quantum chemical calculations we identified not only C–H, C=O and C–OH bonds, but also fingerprints of C–OH(CH2) and C=C bonds. The relatively low intensity of C=O transitions implies that the monohydrated form of methylglyoxal is not favored in the solutions. Instead, the spectral intensity is stronger in regions where products of aldol condensation and enol tautomers of the monohydrates contribute. The addition of salts was found to introduce only very minor changes to absorption energies and relative intensities of the observed absorption features, indicating that XAS in the near-edge region is not very sensitive to these intermolecular organic–inorganic interactions at the studied concentrations. The identified structures of glyoxal and methylglyoxal in an aqueous environment support the uptake of these compounds to the aerosol phase in the presence of water and their contribution to secondary organic aerosol formation.

On the length of lecithin reverse wormlike micelles induced by inorganic salts: Binding site matters

Previous studies have shown that the addition of inorganic salts to lecithin organosols induces long wormlike micelles that lead to organogels. The viscosity of the micellar solution greatly increases with the increasing concentration of the inorganic salt until gelation, but interestingly, it dramatically drops after the gel regime. Although the growth mechanism has been rationally proposed, the reason for the decrease in viscosity remains unclear. In this study, we investigated the rheological behaviors and the self-assembled structures of the lecithin wormlike micelles induced by LiCl, CaCl2, and LaCl3 in cyclohexane. We found that the decrease in viscosity accompanies a shortening in the length of the wormlike micelles. Meanwhile, the study on the interactions between lecithin and the inorganic salts by FTIR shows that the inorganic salts move from the saturated phosphate and choline region to the ester linkage region on lecithin as the viscosity drops. We suggest the movement of the excess inorganic salts alters the effective molecular geometry, which in turn breaks the long wormlike micelle into short ones, thus causing the viscosity to decrease. In other words, the binding sites of the inorganic salts in lecithin headgroups is a key factor that determines the self-assembled structures of lecithin reverse micelles.

Ternary ZnO/Co3O4/NiO inherited layered core-shell structure from a double template for high performanced supercapacitor

Relying on seed method, a double template ZIF-8@ZIF-67 with a layered core-shell structure was made, which is used as a sacrificial template in the next steps. After going through loading process with solvent thermal method and calcination process, ZIF-8@ZIF-67 was etched and calcined into ternary ZnO/Co3O4/NiO successfully. Besides, benefiting from right amount of the addition of inorganic salts, the optimized ZnO/Co3O4/NiO-2 (ZCN-2) shows the outstanding performance in its morphologic structure and electrochemical performance. In the case of a current density of 1 A g−1, the high specific capacitance of 1119.11 C g−1 can be calculated in ZCN-2. In addition, at 10 A g−1, the capacitance value can maintain 93.75% after experiencing 5000 cycles of charging and discharging. The maximum energy density of the assembled ZCN-2//activated carbon (AC) asymmetric supercapacitor can reach 95.82 Wh kg−1, which is really outstanding in the present research achievements. After experiencing charge-discharge cycles with the number of 10,000 times in the case of a current density of 10 A g−1, the cycling stability of this supercapacitor can reach 94.53% of the initial value. And after a charge, the device connected by two supercapacitors can make a light emitting diode (LED) shine up to 30 min successfully.

Suppressing carboxylate nucleophilicity with inorganic salts enables selective electrocarboxylation without sacrificial anodes.

Although electrocarboxylation reactions use CO2 as a renewable synthon and can incorporate renewable electricity as a driving force, the overall sustainability and practicality of this process is limited by the use of sacrificial anodes such as magnesium and aluminum. Replacing these anodes for the carboxylation of organic halides is not trivial because the cations produced from their oxidation inhibit a variety of undesired nucleophilic reactions that form esters, carbonates, and alcohols. Herein, a strategy to maintain selectivity without a sacrificial anode is developed by adding a salt with an inorganic cation that blocks nucleophilic reactions. Using anhydrous MgBr2 as a low-cost, soluble source of Mg2+ cations, carboxylation of a variety of aliphatic, benzylic, and aromatic halides was achieved with moderate to good (34–78%) yields without a sacrificial anode. Moreover, the yields from the sacrificial-anode-free process were often comparable or better than those from a traditional sacrificial-anode process. Examining a wide variety of substrates shows a correlation between known nucleophilic susceptibilities of carbon–halide bonds and selectivity loss in the absence of a Mg2+ source. The carboxylate anion product was also discovered to mitigate cathodic passivation by insoluble carbonates produced as byproducts from concomitant CO2 reduction to CO, although this protection can eventually become insufficient when sacrificial anodes are used. These results are a key step toward sustainable and practical carboxylation by providing an electrolyte design guideline to obviate the need for sacrificial anodes.

Efficient Regulation of the Behaviors of Silk Fibroin Hydrogel via Enzyme-Catalyzed Coupling of Hyaluronic Acid.

Pure silk fibroin (SF) hydrogel exhibits poor elasticity and low water retention ability, owing to the compact crystalline structure and high content of hydrophobic amino acids. Herein, a composite double-network hydrogel of SF and tyramine-modified hyaluronic acid (mHA) was constructed, via the laccase-catalyzed coupling reactions between the phenolic hydroxyl groups from SF and mHA chains. The obtained hydrogel exhibits improved structural stability and flexibility compared to pure SF hydrogel. Meanwhile, the swelling ratio, mechanical property, drug loading, and release behaviors can be readily regulated by alcoholization, altering pH value, and ionic strength of soaking solutions. Increasing pH values promoted the swelling capacity of SF/mHA hydrogel, resulting in an efficient loading of cationic drugs and sustained release of anionic drugs as well. The addition of inorganic salts reduced electrostatic repulsion in the hydrogel scaffold, accompanying with a noticeable improvement of toughness. Furthermore, alcohol treatment induced conformation changes of fibroin protein, and the composite hydrogel achieved a higher fracture and improved elasticity. The present work provides a biological alternative to regulate the mechanical behavior, drug loading, and sustained release capacity of the SF-based hydrogel.

Green synthesis of bentonite-supported iron nanoparticles as a heterogeneous Fenton-like catalyst: Kinetics of decolorization of reactive blue 238 dye

This study aimed to synthesize green tea nano zero-valent iron (GT-NZVI) and bentonite-supported green tea nano zero-valent iron (B-GT-NZVI) nanoparticles using green tea extracts in an environmentally sustainable way. Bentonite was used as a support material because it disperses and stabilizes GT-NZVI, and it helps to reduce the cost, increase the adsorption capacity of GT-NZVI, and decrease the optimum amount of GT-NZVI used in Fenton-like oxidation. A scanning electron microscope, an atomic force microscope, and a Fourier transform infrared spectroscope were used to characterize GT-NZVI and B-GT-NZVI, while the zeta potential was measured to evaluate the stability of iron nanoparticles. The decolorization kinetics of reactive blue 238 (RB 238) dye in the aqueous phase in the Fenton-like oxidation process were investigated as well. The effects of various experimental conditions such as reaction time, dosages of catalysts, concentration of H2O2, temperature, addition of inorganic salts, and other parameters were investigated. The results show that the oxidative degradation efficiencies of RB 238 dye catalyzed by GT-NZVI and B-GT-NZVI were 93.5% and 96.2%, respectively, at the optimum reaction conditions as follows: c(H2O2) = 5 mmol/L, ρ(GT-NZVI) = 0.5 g/L or ρ(B-GT-NZVI) = 0.5 g/L, c(RB 238 dye) = 0.05 mmol/L, and pH = 2.5 at 180 min. The best catalytic performance was exhibited when B-GT-NZVI was used. Three kinetic models were employed, and the second-order model was found to be the best model representing the experimental kinetic data of RB 238 dye. The value of activation energy decreased from 38.22 kJ/mol for GT-NZVI to 14.13 kJ/mol for B-GT-NZVI. This indicates that the effect of B-GT-NZVI in decreasing the energy barrier is more pronounced than that of the GT-NZVI catalyst, leading to improved Fenton-like oxidation processes.

Challenges of influencing cellular morphology by morphology engineering techniques and mechanical induced stress on filamentous pellet systems-A critical review.

Filamentous microorganisms are main producers of organic acids, enzymes, and pharmaceutical agents such as antibiotics and other active pharmaceutical ingredients. With their complex cell morphology, ranging from dispersed mycelia to dense pellets, the cultivation is challenging. In recent years, various techniques for tailor‐made cell morphologies of filamentous microorganisms have been developed to increase product formation and have been summarised under the term morphology engineering. These techniques, namely microparticle‐enhanced cultivation, macroparticle‐enhanced cultivation, and alteration of the osmolality of the culture medium by addition of inorganic salts, the salt‐enhanced cultivation, are presented and discussed in this review. These techniques have already proven to be useful and now await further proof‐of‐concept. Furthermore, the mechanical behaviour of individual pellets is of special interest for a general understanding of pellet mechanics and the productivity of biotechnological processes with filamentous microorganisms. Correlating them with substrate uptake and finally with productivity would be a breakthrough not to be underestimated for the comprehensive characterisation of filamentous systems. So far, this research field is under‐represented. First results on filamentous pellet mechanics are discussed and important future aspects, which the filamentous expert community should deal with, will be presented and critically discussed.

Thermodynamic Investigation of Increased Luminescence in Indium Phosphide Quantum Dots by Treatment with Metal Halide Salts.

Increasing the quantum yields of InP quantum dots is important for their applications, particularly for use in consumer displays. While several methods exist to improve quantum yield, the addition of inorganic metal halide salts has proven promising. To further investigate this phenomenon, InP quantum dots dispersed in tetrahydrofuran were titrated with ZnCl2, ZnBr2, and InCl3. The optical properties were observed, and the reactions were studied by using quantitative 1H NMR and thermodynamic measurements from isothermal titration calorimetry. These measurements contradict the previously hypothesized reaction mechanism in which metal halide salts, acting as Z-type ligands, passivate undercoordinated anions on the surface of the quantum dots. This work provides evidence for a newly proposed mechanism wherein the metal halide salts undergo a ligand exchange with indium myristate. Thermodynamic measurements prove key to supporting this new mechanism, particularly in describing the organic ligand interactions on the surface. An Ising model was used to simulate the quantum dot surface and was fit by using thermodynamic and 1H NMR data. Together, these data and the proposed exchange mechanism provide greater insight into the surface chemistry of quantum dots.

Flocculation-to-adsorption transition of novel salt-responsive polyelectrolyte for recycling of highly polluted saline textile effluents

Herein, a new salt responsive starch flocculant (SSF) via starch etherification with butyl glycidyl ether (BGE) and 2-chloro-4,6-diethylamino-[1,3,5]-triazine (CDAT) was reported as highly salt-responsive polymer. The resulting polymer exhibits a reversible switch from dissolution to precipitation in response to slight external salt stimuli due to the integration of highly charged CDAT moiety. The extent of phase separation, relative solubility and residual polymer in water solution could be precisely modulated by changing the salt concentration and the type of counter ions. The results demonstrated that dyes removal is salt dependent, and that the addition of inorganic salt leads to a pronounced broadening of flocculation window. The as-prepared polymers experience an obvious transition from flocculation to adsorption processes with an increasing salt concentration from 0 to 100 g/L due to the salt-triggered switchable solubility of SSF. Two different mechanisms combined the coagulation and adsorption may be involved in dye decolourization from saline reactive dyeing effluents. The beneficial effect of salt-sensitive flocculant was found to be more significant in reuse of saline wastewater for fabric dyeing, in which the flocculant residuals are significantly low (less than 10.9%). After flocculation and sedimentation, the clarified saline wastewater can be readily recovered and reused three times while retaining high-quality colour reproduction. The salt-driven switchable solubility of polymer from water-soluble flocculants to solid-state adsorbents offers a possibility to overcome the limitations of industrial flocculation processes, such as a narrow flocculation window and high polymer residuals at flocculant overdose.

Comparative Study Between Metronidazole Residues Disposal by Using Adsorption and Photodegradation Processes onto MgO Nanoparticles

The photodegradation and adsorption processes of metronidazole (MNZ) was conducted utilizing the batch reactor onto magnesium oxide nanoparticles (MgO NP) as the catalyst surface affected by UV radiation, initial concentration of MNZ, pH, catalyst loading, inorganic salts addition, time, and temperature. Chemical composition and morphological properties of the prepared MgO NP can also be portrayed by several techniques such as XRD, EDX, SEM, and TEM, while GC–MS analysis was used to monitor the photodegradation pathway for MNZ molecules. The results indicated that the actual removal of 93.2% of 80 mg/L MNZ present in 25 mL of a solution containing 0.1 mg/L of MgO NP could be distributed as 35.7% for maximum adsorption and 57.5% for degradation efficiency during 180 min. The degradation process is mainly of two steps; dark adsorption experiment, and photocatalytic degradation performance. Hence, Kinetic analyses indicate that adsorption constant estimated in dark conditions is smaller than the adsorption equilibrium constant derived from the Langmuir–Hinshelwood kinetic model through photodegradation of MNZ that follows pseudo-first-order kinetic. The adsorption isotherm result specified that the adsorption nature is chemisorption and fit Langmuir model, as well as thermodynamic results indicated that it is a nonspontaneous and endothermic reaction.

Effect of hydrocarbon chain length of aliphatic solvents on the reverse self-assembly of lecithin and monovalent ion mixtures

Surfactants are used as organogelators, which form surfactant-based gels in nonpolar solvents. One of the well-known surfactants that form organogels is lecithin, which self-assembles into reverse spherical micelles in nonpolar solvents. When inorganic salts are added to lecithin solutions, the reverse spherical micelles transform into long reverse cylindrical micelles, giving rise to organogels. Although previous studies have shown that the addition of inorganic salts to lecithin solutions can induce the gel formation, the solvent effects on the gel formation have not been mapped out in detail. In this study, we systematically investigated the effects of hydrocarbon chain length of alkanes on the self-assembly of lecithin and monovalent ion mixtures. Our findings showed that LiCl, LiBr, LiI, NaBr, NaI, and KI salts formed organogels in the presence of lecithin, whereas NaCl and KBr formed viscoelastic solutions with lecithin. More importantly, with an increase in the hydrocarbon chain length of alkanes, the lecithin/salt mixtures formed gels more efficiently. The gel formation is closely related to the length of the reverse cylindrical micelles, as confirmed by small-angle X-ray scattering analysis. In addition, the length of the cylinders is affected by the interactions between the lecithin head groups and ions, as evidenced by Fourier transform infrared spectroscopy.

Fluorescence quenching of p-tert-buthylthiacalix[4]arene by 1-ethyl-3-methylimidazolium bromide.

The interaction between the ionic liquid 1-ethyl-3-methylimidazolium bromide (EMIMBr) and the macrocyclic compound p-tert-buthylthiacalix[4]arene (TC4) in solution ethanol/water 3/1 V/V was investigated by spectrophotometry and spectrofluorimetry. The UV-Vis spectra of the system (EMIMBr+TC4) were completely additive. The addition of EMIMBr decreases the fluorescence of the TC4 significantly, excited at 325.0nm. The Stern-Volmer quenching constants were determined at different temperatures (15.0, 25.0, and 35.0 °C), and the obtained values were the same, with an average value of KQav=(3.8±0.9) 103M-1 for the quenching constant. No changes in the emission spectra of TC4 were obtained by the addition of inorganic salts, such as NaCl, KBr, NH4Cl, and NH4PF6 or the organic compound N-methylimidazole (NMI). More evidence of EMIMBr-TC4 interaction was found with the determination of the fluorescence lifetime and the anisotropy of the mixture. Also, the slope of the quenching plot was the analytical sensitivity of calibration for EMIMBr using TC4 as an indirect sensor, and a LOD=(26±2) μM was obtained.

A modified quick, easy, cheap, effective, rugged, and safe method with hydrophobic natural deep eutectic solvent as extractant and analyte protectant for analyzing pyrethroid residues in tomatoes.

In this work, a novel quick, easy, cheap, effective, rugged, and safe technique with hydrophobic natural deep eutectic solvent as both extractant and analyte protectant was developed and combined with gas chromatography-tandem mass spectrometry to analyze pyrethroid residues in tomatoes. Eight hydrophobic natural deep eutectic solvents were first evaluated as analyte protectants and those with decanoic acid or lactic acid as hydrogen bond donor were demonstrated to be effective in compensating for the matrix effects of pyrethroids in the gas chromatography system. Hence, they were added to solvent standards for correcting the quantitation errors instead of matrix-matched calibration standards. Then the abilities of these acid-based deep eutectic solvents to extract pyrethriods from tomatoes were evaluated. Results showed the recoveries of all pyrethroids reached to over 80% with only 5mL menthol:decanoic acid (1:1) used, and good phase separation was easily achieved without the addition of inorganic salt in the extraction step, indicating hydrophobic natural deep eutectic solvent could be a green substitute for acetonitrile in the quick, easy, cheap, effective, rugged, and safe extraction. Compared with the conventional method, the proposed protocol improved the recoveries, reduced the matrix effects, and simplified the extraction step, demonstrating to be an effective, fast, and green method.

High-Value Organic Acid Recovery from First-Generation Bioethanol Dunder Using Nanofiltration

Nanofiltration (NF) was investigated for the recovery of platform chemicals, specifically, succinic acid, from high-strength bioethanol waste (dunder). Conventional methods focusing on chemical precipitation entail poor selectivity in complex matrices and are inherently expensive owing to the consumption of large volumes of chemicals and the generation of excess by-product sludge. For these reasons, three commercially available NF membranes with varying molecular weight cut-off were screened in a dead-end configuration to benchmark transmission behavior at different solution chemistries including pH, feed pressure, concentration, and ionic strength prior to filtration with the industrial effluent. Examination of behavior with model solutions only reveals that both NF270 and NTR-7450 membranes exhibit a succinic acid permeation above 80% irrespective of pH and solute concentration, while the addition of inorganic salts, in particular, divalent species, lowered the transmission of succinic acid with all membranes, in particular, NF90. Measurements of the surface charge (zeta potential) before and after filtration of the industrial effluent indicate a shift toward more positive values for the polyamide membranes (NF90 and NF270) within the pH range of 2-10. This change in surface charge was attributed to the formation of complexes between humic compounds and divalent cations present in elevated concentrations. Considerable fouling was observed for all membranes with the mean permeate flux around 2 L/m(2)h at 5 bar for the NF270 and NTR-7450 membranes; however, findings from deionized water rinsing suggest that the majority of foulants reside within the reversible fouling layer. Finally, size exclusion chromatography (liquid chromatography-organic carbon detection) findings highlight substantial (>70%) rejection of biopolymers, humics, building blocks, and low-molecular-weight neutral species following filtration with all membranes. Overall, this work demonstrates the merits and potential of nanofiltration in the recovery of high-value organic acids from concentrated bioethanol waste.

Salt induced fluffy structured electrospun fibrous matrix

Electrospinning is a widely investigated and used technique for creating nano and microfibres which has a wide range of medical and pharmaceutical applications. For cell culturing and tissue engineering, it is a greatly investigated method because it resembles the extracellular matrix. Changing the electrospinning parameters we affect the properties of these systems to fine-tune it for our needs. To create a high porosity fibrous mesh for culturing different cells in a suitable three-dimensional way, we need to step forward from conventional electrospinning.In this paper, we are presenting a strategy involving the addition of inorganic salts to electrospinning solution to reproducibly synthesize nano and microfibrous fluffy 3D structures from polysuccinimide (a biocompatible and biodegradable polymer). Effect of different concentrations of LiCl, MgCl2 and CaCl2 on fibre properties are presented. Results show that the 3D structured fibrous meshes were produced in the presence of LiCl, MgCl2 or CaCl2 in a narrow concentration range. To understand the effect of salt on the resulting meshes characterization of the ion-ion and ion-solvent interactions were carried out using vibration spectroscopy and density functional theory calculation.

Comparison of four oxidants activated through tetraacetylethylenediamine for developing sustainable and rapid degradation of organic dye

AbstractFour common oxidants, including hydrogen peroxide (H2O2), sodium percarbonate (SPC), sodium perborate (SPB) and sodium persulphate (SPS), were activated with tetraacetylethylenediamine (TAED) to degrade an azo dye, CI Reactive Red 195, in water, for building a novel and rapid oxidative system comprising the merits of cost‐effectiveness and high sustainability. Elevated temperature and high pH level enhanced the activation effect of TAED for accelerating dye degradation. Peracetic acids were confirmed to be the main oxidative species for dye degradation in four TAED/oxidant systems. Hydroxyl radicals and sulphate radicals were also involved in dye degradation in the TAED/SPS system, which showed a stronger oxidative capacity than the other three systems over a wide pH range. More importantly, the addition of inorganic salts or surfactants also favoured the dye degradation in TAED/oxidant systems. Although a slow mineralisation process of the dye was found when the TAED/SPC or SPS system was used, low‐toxic intermediates were detected after the degradation.