Aniline In Aqueous Solution Research Articles

Evidence for Superoxide-Initiated Oxidation of Aniline in Water by Pulsed, Atmospheric Pressure Plasma.

Plasma-driven solution electrochemistry (PDSE) uses plasma-generated reactive species to drive redox reactions in solution. Nonthermal, atmospheric pressure plasmas, when irradiating water, produce many redox species. While PDSE is a promising chemical tool, there is limited insight into the mechanisms of the reactions due to the variety of short-lived reagents produced. In this study, we use aniline as a model system for studying redox mechanisms of PDSE. We show that the plasma irradiation of aqueous aniline solutions drives the formation of polyaniline oligomer, which is suppressed under acidic starting conditions. The addition of (2,2,6,6-Tetramethylpiperidin-1-yl)oxyl (TEMPO), a radical scavenger, decreases the formation of oligomer by 80%, and the addition of superoxide dismutase fully hinders oligomerization. These results lead us to conclude that the oligomerization of aniline by plasma irradiation is initiated by superoxide. This discovery provides novel insights into PDSE mechanisms and illustrates a potential method of harnessing superoxide for chemical reactions.

Synthesis and Characterization of Polyaniline Emeraldine Salt (PANI-ES) Colloids Using Potato Starch as a Stabilizer to Enhance the Physicochemical Properties and Processability.

Conductive polymers, such as polyaniline (PANI), have interesting applications, ranging from flexible electronics, energy storage devices, sensors, antistatic or anticorrosion coatings, etc. However, the full exploitation of conductive polymers still poses a challenge due to their low processability. The use of compatible stabilizers to obtain dispersible and stable colloids is among the possible solutions to overcome such drawbacks. In this work, potato starch was used as a steric stabilizer for the preparation of colloidal polyaniline (emeraldine salt, ES)/starch composites by exploiting the oxidative polymerization of aniline in aqueous solutions with various starch-to-aniline ratios. The polyaniline/starch bio-composites were subjected to structural, spectroscopic, thermal, morphological, and electrochemical analyses. The samples were then tested for their dispersibility/solubility in a range of organic solvents. The results demonstrated the formation of PANI/starch biocomposites with a smaller average size than starch particles, showing improved aqueous dispersion and enhanced solubility in organic solvents. With respect to previously reported PANI-EB (emeraldine base)/starch composites, the novel colloids displayed a lower overall crystallinity, but the conductive nature of PANI-ES enhanced its electrochemical properties, resulting in richer redox chemistry, particularly evident in its oxidation behavior, as observed through cyclic voltammetry. Finally, as proof of the improved processability, the colloids were successfully integrated into a thin polyether sulfone (PES) membrane.

Quenching and enhancement mechanisms of a novel Cd-based coordination polymer as a multiresponsive fluorescent sensor for nitrobenzene and aniline

BackgroundNitroaromatic compounds are inherently hazardous and explosive, so convenient and rapid detection strategies are needed for the sake of human health and the environment. There is an urgent demand for chemical sensing materials that offer high sensitivity, operational simplicity, and recognizability to effectively monitor nitroaromatic residues in industrial wastewater. Despite its importance, the mechanisms underlying fluorescence quenching or enhancement in fluorescent sensing materials have not been extensively researched. The design and synthesis of multiresponsive fluorescent sensing materials have been a great challenge until now. ResultsIn this study, a one-dimensional Cd-based fluorescent porous coordination polymer (Cd–CIP-1) was synthesized using 5-(4-cyanobenzyl)isophthalic acid (5-H2CIP) and 4,4′-bis(1-imidazolyl)biphenyl (4,4′-bimp) and used for the selective detection of nitrobenzene in aqueous solution by fluorescence quenching, with a limit of detection of 1.38 × 10−8 mol L−1. The presence of aniline in the Cd–CIP-1 solution leads to the enhancement of fluorescence property. Density functional theory and time-dependent density functional theory calculations were carried out to elucidate the mechanisms of the fluorescence changes. This study revealed that the specific pore size of Cd–CIP-1 facilitates analyte screening and enhances host-guest electron coupling. Furthermore, π–π interactions and hydrogen bond between Cd–CIP-1 and the analytes result in intermolecular orbital overlap and thereby boosting electron transfer efficiency. The different electron flow directions in NB@Cd–CIP-1 and ANI@Cd–CIP-1 lead to fluorescence quenching and enhancement. Significance and noveltyThe multiresponsive coordination polymer (Cd–CIP-1) can selectively detect nitrobenzene and recognize aniline in aqueous solutions. The mechanism of fluorescence quenching and enhancement has been thoroughly elucidated through a combination of density functional theory and experimental approaches. This study presents a promising strategy for the practical implementation of a multiresponsive fluorescent chemical sensor.

Preparation of phenolic hydroxyl-modified hyper-crosslinked polymers and their adsorption performance towards small molecular aromatic amines

Herein, three phenolic hydroxyl-modified hyper-crosslinked polymers were synthesized according to two-step Friedel-Crafts alkylation, and they were applied to adsorb small aromatic amines in aqueous and organic solvents. The first low-temperature Friedel-Crafts at 313 K introduced massive phenolic –OH to the intermediates, then the second high-temperature Friedel-Crafts at 353 K, also known as post-crosslinking reaction, brought a hyper-crosslinked skeleton composed of plentiful rigid methylene bridges to the target products, greatly enhancing the Brunauer-Emmett-Teller (BET) surface area (SBET) and total pore volume (Vtotal) of the polymers. In aqueous solution, the HCPS-BNAP-FDA had great potential for efficient adsorption of aniline and p-nitroaniline (p-NANL), and the Langmuir model predicted that their maximum capacities (qmax) were 209.25 mg/g and 277.30 mg/g, respectively. In cyclohexane solution, the qmax of aniline on HCPS-BNAP-FDA was predicted to be 202.38 mg/g. The removal aniline in aqueous solution could exceed 95 % when the original concentration was less than 200 mg/L, and the final concentration was 0.12 mg/L, much lower than the emission limit of China (GB 4287–2012, China). The polymer with 1,4-bis(chloromethyl)benzene (DCX) as crosslinking agent had the highest SBET (1282 m2/g) and the best adsorption performance for aniline (qmax, 258.73 mg/g). The adsorption mechanism demonstrated that the grafting of phenolic –OH groups improved the adsorption performance, as the possible hydrogen bonds and acid-base interactions. The micropores added via post-crosslinking also achieved a significant increase in adsorption capacity, that is, the pore filling adsorption mechanism.

Efficient degradation and mineralization of aniline in aqueous solution by new dielectric barrier discharge non-thermal plasma

Aniline is a priority pollutant that is unfavorable to the environment and human health due to its carcinogenic and mutagenic nature. The performance of the dielectric barrier discharge reactor was examined based on the aniline degradation efficiency. Different parameters were studied and optimized to treat various wastewater conditions. Role of active species for aniline degradation was investigated by the addition of inhibitors and promoters. The optimum conditions were 20 mg/L initial concentration, 1.8 kV applied voltage, 4 L/min gas flow rate and a pH of 8.82. It was observed that 87% of aniline was degraded in 60 min of dielectric barrier discharge treatment at optimum conditions. UV–Vis spectra showed gradual increase in the treatment efficiency of aniline with the propagation of treatment time. Mineralization of AN was confirmed by TOC measurement and a decrease in pH during the process. To elicit the aniline degradation route, HPLC and LC-MS techniques were used to detect the intermediates and byproducts. It was identified that aniline degraded into different organic byproducts and was dissociated into carbon dioxide and water. Comparison of the current system with existing advanced oxidation processes showed that DBD has a remarkable potential for the elimination of organic pollutants.

Diverse Methods to Nanomanufacture Colloidal Dispersions of Polyaniline without Templates

Different methods which could be used to produce colloidal dispersions of polyaniline (PANI) nano-objects without templates are described. While the methods are non-deterministic, different nano-objects (nanospheres, nanofibers, nanobelts, nanorice, nanotubes, nanorods, nanodisks, etc.) can be produced. Those most used are: (i) solution polymerization with steric stabilizers (SPS) to produce nanospheres, (ii) interfacial polymerization (IP) to produce nanofibers and (iii) solution polymerization in the presence of additives (SPA) to produce nanotubes. Oxidation of aniline in aqueous solution could produce nanotubes, nanofibers and other shapes by controlling mass transport/concentration of reactants, pH, and the presence of oligomers/additives. The different models proposed to explain the formation of various nano-objects are discussed. Mechanochemical polymerization (MCP) could produce nanofibers or nanospheres by controlling the aniline/oxidant ratio. PANI nanospheres of tunable sizes can also be produced by nanoprecipitation (NPT) of preformed PANI from its solutions using an antisolvent. The geometrical constraints to the small nano-objects made of high-molecular-weight rigid polymers are described. The conditions to produce nanostructures also affect the intrinsic properties of PANI (conductivity, crystallinity, and electroactivity). Selected technological applications of PANI nano-objects manufactured as colloidal dispersions without templates are discussed. Based on the reviewed work and models, future lines of work are proposed.

Facile synthesis of polyaniline catalyzed by carbon fiber for supercapacitor applications

Polyaniline (PAni) widely studied conductive polymer due to its incredible versatility, electrical properties, and low cost. PAni usually is produced by chemical or electrochemical synthesis. However, these processes either generate a large amount of waste or are expensive and produce a small amount. The catalytic system incorporated into the PAni synthesis can be a strategic way to develop clean and low-cost processes. Therefore, we propose a synthesis of PAni catalyzed by carbon fiber (CF) reported for the first time. The procedure is to immerse the CF in an aqueous solution of aniline and H2SO4, at room temperature, in an open flask. Tests were carried out to investigate the CF as a catalyst and the molecular oxygen as an oxidant in the polymerization reaction. The samples were characterized by scanning electron microscopy, Raman spectroscopy, infrared spectroscopy, and X-ray photoelectron spectroscopy. According to the analyses, the reaction catalysts are heteroatoms on the fiber surface. Molecular oxygen present in atmospheric air is the oxidant of the reaction. The method is environmentally friendly, simple, and economical route to produce a conductive form of PAni on carbon fiber. The composite produced was evaluated as a possible electrode for a supercapacitor, and presented interesting results for application in energy storage devices.

Heterogeneous Catalytic Oxidation for the Degradation of Aniline in Aqueous Solution by Persulfate Activated with CuFe2O4/Activated Carbon Catalyst

AbstractThis work investigated the degradation of aniline in aqueous solution by PMS activated with CuFe2O4/activated carbon heterogeneous catalyst. Firstly, catalyst which was successfully synthesized by impregnation and calcination process was fully characterized. Next, influences of factors in degradation on this system were explored. Under optimum process conditions, system could achieve TOC removal rate of 87 % in 2 hours. Then the stability of the catalyst was proved. In addition, the synergistic effect between CuFe2O4 and activated carbon was proposed in PMS activation at both low and high concentrations. Furthermore, it was observed that CuFe2O4/activated carbon could also activate PMS at low concentration. Finally, was suggested as the main activated species in this system by characterization and analysis. It is concluded that CuFe2O4/activated carbon catalyst could be used as an effective catalyst to activate PMS for the degradation of aniline.

Physicochemical Properties and Atomic-Scale Interactions in Polyaniline (Emeraldine Base)/Starch Bio-Based Composites: Experimental and Computational Investigations.

The processability of conductive polymers still represents a challenge. The use of potato starch as a steric stabilizer for the preparation of stable dispersions of polyaniline (emeraldine base, EB) is described in this paper. Biocomposites are obtained by oxidative polymerization of aniline in aqueous solutions containing different ratios of aniline and starch (% w/w). PANI-EB/Starch biocomposites are subjected to structural analysis (UV-Visible, RAMAN, ATR, XRD), thermal analysis (TGA, DSC), morphological analysis (SEM, Laser Granulometry), and electrochemical analysis using cyclic voltammetry. The samples were also tested for their solubility using various organic solvents. The results showed that, with respect to starch particles, PANI/starch biocomposites exhibit an overall decrease in particles size, which improves both their aqueous dispersion and solubility in organic solvents. Although X-ray diffraction and DSC analyses indicated a loss of crystallinity in biocomposites, the cyclic voltammetry tests revealed that all PANI-EB/Starch biocomposites possess improved redox exchange properties. Finally, the weak interactions at the atomic-level interactions between amylopectin–aniline and amylopectin–PANI were disclosed by the computational studies using DFT, COSMO-RS, and AIM methods.

Structural and optical properties of polyaniline/nickel ferrite nanocomposites

Polyaniline/ferrite nanocomposites have attracted increasing attention because they offer the possibility of a new generation of nanostructure materials with advanced applications like electromagnetic interference shielding, rechargeable batteries, corrosion devices due to their flexibility, inexpensive and easy of synthesis. Polyaniline (PANI) containing MFe2O4 were prepared by in-situ polymerization of aniline in aqueous solution (Where M-represent divalent metal cation, M2+ = Ni2+). PANI reduces the agglomeration of nanosized nickel ferrite (NiFe2O4) particles which is good for the stabilization of nanoparticles. The investigation of structural, morphological and optical properties was carried out for the synthesized PANI/NiFe2O4 nanocomposites using X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Ultraviolet visible spectrophotometer (UV-Vis). XRD revealed that the structure of NiFe2O4 nanoparticles is spinel with space group Fd3m and crystallite size 14 nm. Lattice parameter was found to increases with NiFe2O4 concentration in PANI and this may be due to the larger ionic radius of the Ni2+ ion. XRD pattern of PANI/NiFe2O4 nanocomposites at different ferrite molar percent are just the superposition of those of polyaniline and ferrite nanoparticles. Transmission electron microscopy of PANI/NiFe2O4 nanocomposites show increase in particle size over pure a NiFe2O4 nanoparticles which is relevant with XRD results. UV-Visible absorption spectroscopy of PANI/NiFe2O4 nanocomposites shows two absorption bands in range of 300-350 nm and 600-650 nm which reflects interaction of ferrite nanoparticles with PANI. Copyright © 2017 VBRI Press.

A fluorescent 1,4-bib-pillared Zn-MOF sensor for highly sensitive detection of Dy3+, nitrobenzene and aniline in aqueous solution

A luminous Zn-MOF(1), formulated as [Zn2 (3-DBB) (1,4-bib)1.5 (Ac)]·H2O (3-H3DBB ​= ​3-(3,5-dicarboxylato benzyloxy) benzoic acid and 1,4-bib ​= ​1,4-bis (1-imidazoly)benzene) has been prepared hydrothermally. Structural analysis shows that Zn ions linked by 3-DBB3- into 2D brick-wall-like double layer-like structure, further assembling 3D framework by 1,4-bib pillared ligands. The Zn-MOF has been discovered to selectively detect Dy3+ by the luminescent enhancement with the detection limit (LOD) of 1.16 ​× ​10−5 ​M, and is highly selective and sensitive to nitrobenzene (LOD:1.40 ​× ​10−6 ​M) and aniline (LOD:2.03 ​× ​10−7 ​M) as well. The theoretical calculation and absorption spectra results verify the correctness of organic solvents detection. Therefore, the material might be used as a multi-response luminescent sensor.

Hybrid Antibacterial and Electro-conductive Coating for Textiles Based on Cationic Conjugated Polymer.

The development of efficient synthetic strategies for incorporating antibacterial coatings into textiles for pharma and medical applications is of great interest. This paper describes the preparation of functional nonwoven fabrics coated with polyaniline (PANI) via in situ polymerization of aniline in aqueous solution. The effect of three different monomer concentrations on the level of polyaniline coating on the fibers comprising the fabrics, and its electrical resistivities and antibacterial attributes, were studied. Experimental results indicated that weight gains of 0.7 and 3.0 mg/cm2 of PANI were achieved. These levels of coatings led to the reduction of both volume and surface resistivities by several orders of magnitude for PANI-coated polyester-viscose fabrics, i.e., from 108 to 105 (Ω/cm) and from 109 to 105 Ω/square, respectively. Fourier Transform Infrared (FTIR) Spectroscopy and Scanning Electron Microscopy (SEM) confirmed the incorporation of PANI coating with an average thickness of 0.4–1.5 µm, while Thermogravimetric Analysis (TGA) demonstrated the preservation of the thermal stability of the pristine fabrics. The unique molecular structure of PANI, consisting of quaternary ammonium ions under acidic conditions, yielded an antibacterial effect in the modified fabrics. The results revealed that all types of PANI-coated fabrics totally killed S. aureus bacteria, while PANI-coated viscose fabrics also demonstrated 100% elimination of S. epidermidis bacteria. In addition, PANI-coated, PET-viscose and PET fabrics showed 2.5 log and 5.5 log reductions against S. epidermidis, respectively.

Extreme ultraviolet time-resolved photoelectron spectroscopy of aqueous aniline solution: enhanced surface concentration and pump-induced space charge effect

We present extreme ultraviolet (XUV) time-resolved photoelectron spectroscopy (TRPES) of an aqueous aniline solution. One-colour XUV-induced photoemission signal of aniline was observed with much greater intensity than expected from its molar fraction in the bulk solution, indicating that aniline is hydrophobically segregated on the liquid surface. The concentration dependence of the photoelectron intensity is found to be well correlated with the surface concentration of aniline estimated by surface tension measurements. Similar segregation was observed also for phenol in aqueous solution. The enhanced surface concentration of aniline makes its XUV-TRPES to be highly vulnerable to the pump-induced space charge effects (PISC). The PISC caused by a moderate pump intensity was not completely corrected using a simple mean field model, and reduction of the pump pulse intensity was necessary. The spectra measured at lower pump intensity were corrected for PISC, which enabled us to extract the information on the excited state dynamics of aniline in aqueous solution under 240 nm photoexcitation. Two components with lifetime on sub-ps and >100 ps timescales were determined, and the former is ascribed to the solvation dynamics in the S 1 state after the ultrafast internal conversion from the S 3 state and the latter to the subsequent population decay of the S 1 state.

Developing the Ternary ZnO Doped MoS2 Nanostructures Grafted on CNT and Reduced Graphene Oxide (RGO) for Photocatalytic Degradation of Aniline

Transition metal sulfide semiconductors have achieved significant attention in the field of photocatalysis and degradation of pollutants. MoS2 with a two dimensional (2D) layered structure, a narrow bandgap and the ability of getting excited while being exposed to visible light, has demonstrated great potential in visible-light-driven photocatalysts. However, it possesses fast-paced recombination of charges. In this study, the coupled MoS2 nanosheets were synthesized with ZnO nanorods to develop the heterojunctions photocatalyst in order to obtain superior photoactivity. The charge transfer in this composite is not adequate to achieve desirable activity. Therefore, heterojunction was modified by reduced graphene oxide (RGO) nanosheets and carbon nanotubes (CNTs) to develop the RGO/ZnO/MoS2 and CNTs/ZnO/MoS2 ternary nanocomposites. The structure, morphology, composition, optical and photocatalytic properties of the as-fabricated samples were characterized through X-ray diffraction (XRD), Fourier Transform Infrared (FTIR), Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM), Energy-Dispersive X-ray (EDX), elemental mapping, Photoluminescence (PL), Ultraviolet–Visible spectroscopy (UV-VIS), and Brunauer-Emmett-Teller (BET) techniques. The photo-catalytic performance of all samples was evaluated through photodegradation of aniline in aqueous solution. The combination of RGO or CNTs into the ZnO/MoS2 greatly promoted the catalytic activity. However, the resulting RGO/ZnO/MoS2 ternary nanocomposites showed appreciably increased catalytic performance, faster than that of CNTs/ZnO/MoS2. Charge carrier transfer studies, the BET surface area analysis, and the optical studies confirmed this superiority. The role of operational variables namely, solution pH, catalyst dosage amount, and initial concentration of aniline was then investigated for obtaining maximum degradation. Complete degradation was observed, in the case of pH = 4, catalyst dosage of 0.7 g/L and aniline concentration of 80 ppm, and light intensity of 100 W. According to the results of trapping experiments, hydroxyl radical was found to be the main active species in the photocatalytic reaction. Meanwhile, a plausible mechanism was proposed for describing the degradation of aniline upon ternary composite. Moreover, the catalyst showed excellent reusability and stability after five consecutive cycles due to the synergistic effect between its components. Total-Organic-Carbon concentration (TOC) results suggested that complete mineralization of aniline occurred after 210 min of irradiation. Finally, a real petrochemical wastewater sample was evaluated for testing the catalytic ability of the as-fabricated composites in real case studies and it was observed that the process successfully quenched 100% and 93% of Chemical Oxygen Demand (COD) and TOC in the wastewater, respectively.

Characterization and Photo-catalytic Efficiency of MnFe2O4/Zn2SiO4 for Aniline Degradation Using Box-Behnken Experimental Design and Simulated Solar Radiation

In this research, Zn2SiO4 as a support and MnFe2O4 as a main photo-catalyst were individually syn-thesized and MnFe2O4 was fixed on Zn2SiO4 with solid state dispersion method. MnFe2O4 nano pho-to-catalyst was synthesized by co-precipitation method and reflux condition for 12 hours at 85°C in the presence of urea. For identification of catalysts Fourier-transform infrared (FTIR) spectroscopy, Field emission scanning electron microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDXS), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray fluorescence (XRF) and Brunauer-Emmett-Teller (BET) techniques were used. The size of MnFe2O4 was determined about 15 nm after the fixation on the Zn2SiO4. The photo-catalytic efficiency of MnFe2O4/Zn2SiO4 was checked for degradation of aniline aqueous solu-tion utilizing the irradiation of a 1 kW Xe lamp fitted with the AM1.5 filter (to simulate the solar light spectrum) in the presence of H2O2. Degradation process was modeled and optimized successfully ap-plying response surface methodology (RSM) according to Box-Behnken designs. Experiment results were showed that initial concentration of aniline=5.5 ppm, H2O2 initial concentration=5.3 mM, pH=11 and nano photo-catalyst amount =0.4 g/L are optimal conditions and the degradation effi-ciency in this condition achieved is 96%. In the optimum conditions, arrangement of (MnFe2O4/Zn2SiO4)> (MnFe2O4)> (Zn2SiO4) was obtained for efficiency of photo-catalytic degrada-tion of aniline in aqueous solution. Decomposition kinetic equation determined pseudo first order and k=0.0407.

Mineralization of aniline in aqueous solution by sono-activated peroxydisulfate enhanced with PbO semiconductor

Oxidative degradation of aniline in aqueous solution was performed by the sono-activated peroxydisulfate coupled with PbO process, wherein a dramatic synergistic effect was found. Experiments were carried out in the batch-wise mode to investigate the influence of various operation parameters on the sonocatalytic behavior, such as ultrasonic power intensity, peroxydisulfate anion concentrations and PbO dosages. According to the scavenging effect of ethanol, methanol and tert-butyl alcohol, the principal oxidizing agents were presumed to be sulfate radicals descended from peroxydisulfate anions, activated via ultrasound or sonocatalysis of PbO. Based on the results attained from gas chromatograph-mass spectrometer, it was hypothesized that aniline was initially oxidized into iminobenzene radicals, followed with formation of nitrosobenzene, p-benzoquinonimine and nitrobenzene respectively. Condensation of nitrosobenzene with aniline generated azobenzene. Phenol was detected as one of degradation intermediates, which was sequentially converted into hydroquinone and p-benzoquinone.

Degradation of aniline in aqueous solution by dielectric barrier discharge plasma: Mechanism and degradation pathways

The degradation of aniline solution using the dielectric barrier discharge (DBD) plasma was studied in this paper. The results indicated that the initial concentration of aniline, applied voltage and initial pH value affected the removal efficiency of aniline significantly. After 12 min with DBD plasma treatment, 90.2% removal efficiency was achieved at aniline concentration of 100 mg L−1 with an applied voltage of 3.0 kV and pH 8.43. The removal efficiency decreased with the presence of radical scavengers, indicating that hydroxyl radical plays a key role in the degradation process. The removal efficiency increased obviously when Fe2+ was added. Additionally, the intermediate products generated in the degradation process of aniline were analyzed by some analytical techniques, including total organic carbon analysis, ultraviolet-visible spectroscopy, Fourier Transform Infrared spectroscopy, Gas Chromatography-Mass Spectrometer, etc. The results showed that the degradation of aniline was mainly due to the strong oxidizing capacity of hydroxyl radical produced by the DBD plasma system. Based on the intermediate products identified in the study, the possible degradation mechanism and pathways were proposed.

MnO2/Cr2O3/PANI nanocomposites prepared by in situ oxidation polymerization method: Optical and electrical behaviors

ABSTRACTMetal oxide–polyaniline (PANI) nanocomposite with spherical morphologies were prepared in a one‐pot oxidation–reduction method via various salts as reactive oxidants. Aniline monomers polymerize as a shell on the surface of one‐pot prepared metal oxides, when the aqueous solutions of aniline, a free‐radical oxidant, and/or a metallic salt were exposed together. The particle size and morphology of as‐prepared narrowly dispersed PANI nanocomposites were revealed by field emission scanning electron microscope images. Fourier transform infrared spectra of nanocomposites indicate that the PANI exists in the emeraldine form. The ultraviolet–visible analysis not only shows PANI is in the emeraldine form, but also indicates modified optical properties of PANI in the composite form. The hypsochromic shift of the n–π* and polaron transitions of PANI reveals the incorporation of PANI by metal oxides. The direct current (dc) electrical conductivity (σ) of as‐prepared nanocomposites was measured by a four‐probe method in the room temperature. Compared to PANI nanoparticles, the electrical conductivity of the composites increased with the presence of metal oxides in the nanocomposites. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47219.

Thermodynamic Interactions Study of Some Ethylene Glycols in Aqueous Aniline Solutions at Different Temperatures: An Acoustical and Volumetric Approach

With densities and ultrasonic speeds, interactions of aniline with ethylene glycol, diethylene glycol, and triethylene glycol are measured at T = (293.15–308.15) K. From the densities, the (apparen...

Degradation of aniline by electrochemical activation of peroxydisulfate at MWCNT cathode: The proofed concept of nonradical oxidation process

Enhanced elimination of aniline in aqueous solution was achieved by coupling electrosorption of aniline and electrochemical activation of peroxydisulfate (PDS) at multi-walled carbon nanotube (MWCNT) cathode, in which a synergistic effect occurred. It was found that PDS could be effectively activated under a small voltage at MWCNT cathode owing to the specific pore structures of MWCNTs. A nonradical oxidation pathway instead of radical-based oxidation was proposed from the cathodic activation of PDS, wherein PDS molecules with a modified electronic structure was suggested to be the principal reactive species. Meanwhile, the influences of various operation parameters such as electrode potential, PDS concentration, presence of chloride ions on the elimination efficiency, and the stability of MWCNT electrode were also attempted. Therefore, the electrochemical activation of PDS by MWCNT cathode is a promising energy-saving method for the treatment of organic pollutants in wastewater.