Showing papers on "Nitrobenzene published in 2013"
TL;DR: A multifunctional Cu(I) coordination polymer constructed from helical chains showed unusual mechanochromic, sensing of nitrobenzene and photocatalytic properties on degradation of organic dyes.
271 citations
TL;DR: A luminescent two-dimensional (2D) coordination polymer is demonstrated to be a selective sensing material for the straightforward detection of nitrobenzene via a redox fluorescence quenching mechanism.
Abstract: A luminescent two-dimensional (2D) coordination polymer is demonstrated to be a selective sensing material for the straightforward detection of nitrobenzene via a redox fluorescence quenching mechanism.
230 citations
TL;DR: Surface assisted laser desorption/ionization mass spectrometry has been for the first time applied to detect the intermediates and major product of NB through photoelectrocatalytic or photocatalytic reactions, and the result reveals that the reduction of NB to aniline is through nitrosobenzene to phenylhydroxylamine in the photoelectrifying reaction, while via nitro sobenzenes directly in the photocatallytic reaction.
Abstract: A simple hydrothermal method of preparing highly photocatalytic graphene-ZnO-Au nanocomposites (G-ZnO-Au NCs) has been developed. Zinc acetate and graphene oxide are reduced by catechin to form graphene-zinc oxide nanospheres (G-ZnO NSs; average diameter of (45.3 ± 3.7) nm) in the presence of ethylenediamine (EDA) as a stabilizing agent and gold nanorods (Au NRs) at 300 °C for 2 h. Then Au NRs are deposited onto as-formed G-ZnO NSs to form G-ZnO-Au NCs. Upon ultraviolet light activation, G-ZnO-Au NCs (4 mg mL–1) in methanol generates electron–hole pairs. Methanol (hydroxyl group) assists in trapping holes, enabling photogenerated electrons to catalyze reduction of nitrobenzene (NB) to aniline with a yield of 97.8% during a reaction course of 140 min. The efficiency of G-ZnO-Au NCs is 3.5- and 4.5-fold higher than those provided by commercial TiO2 and ZnO NSs, respectively. Surface assisted laser desorption/ionization mass spectrometry has been for the first time applied to detect the intermediates (nitros...
197 citations
TL;DR: In this paper, a Pt-deposited amino-functionalised Ti(IV) metal-organic framework (Pt/Ti-MOF-NH2) was used for hydrogen production and photocatalytic reduction of nitrobenzene under visible-light irradiation.
186 citations
TL;DR: The results imply that graphene-based nanomaterials may effectively mediate the reductive transformation of nitroaromatic compounds and can contribute to the natural attenuation and remediation of these chemicals.
Abstract: The main objective of this study was to test the possibility that graphene-based nanomaterials can mediate environmentally relevant abiotic redox reactions of organic contaminants. We investigated the effect of graphene oxide (GO) on the reduction of nitrobenzene by Na2S in aqueous solutions. With the presence of GO (typically 5 mg/L), the observed pseudofirst-order rate constant (kobs) for the reduction of nitrobenzene was raised by nearly 2 orders of magnitude (from 7.83 × 10–5 h–1 to 7.77 × 10–3 h–1), strongly suggesting reaction mediation by GO. As reflected by the combined spectroscopic analyses, GO was reduced in the beginning of the reaction, and hence the reduced GO (RGO) mediated the reduction of nitrobenzene. It was proposed that the zigzag edges of RGO acted as the catalytic active sites, while the basal plane of RGO served as the conductor for the electron transfer during the catalytic process. Furthermore, changing the pH (5.9–9.1) and the presence of dissolved humic acid (10 mg TOC/L) were f...
154 citations
TL;DR: A functionalized plasmonic Au/TiO2 photocatalyst with an Ag co-catalyst was successfully prepared by the combination of two types of photodeposition methods, and it quantitatively converted nitrobenzene and 2-propanol to aniline and acetone under irradiation of visible light.
109 citations
TL;DR: In this article, a modeling study on simultaneous adsorption of three binary systems (nitrobenzene, aniline and phenol) onto granular activated carbon (GAC) in aqueous solution was performed at 30°C by conducting batch experiments.
72 citations
TL;DR: In this article, the photocatalytic conversion of nitrobenzenes in 2-propanol suspensions of bare titanium(IV) oxide (TiO 2 ) under various conditions was examined.
Abstract: Photocatalytic conversion of nitrobenzenes in 2-propanol suspensions of bare titanium(IV) oxide (TiO 2 ) under various conditions was examined. Aniline and acetone were simultaneously produced almost stoichiometrically from a 2-propanol suspension of TiO 2 containing nitrobenzene under deaerated conditions without the use of a precious metal. Nitrobenzenes having another reducible group such as vinyl, chloro and bromo were chemoselectively reduced to corresponding aminobenzenes in 2-propanol suspensions of a TiO 2 photocatalyst with an almost stoichiometric amount of acetone. Photocatalytic reduction of nitrobenzene and oxidation of 2-propanol occurred even in the presence of oxygen, and no re-oxidation of anilines occurred.
67 citations
01 Jan 2013
TL;DR: In this article, the analysis of cobalt oxide (Co 3O4) nanoparticles has been carried out by thermal decomposition of a cobalt hydroxide synthesized from cobalt acetate, ammonium hyroxide and 10% glycerol.
Abstract: Cobalt oxide (Co 3O4) nanoparticles were successfully prepared by thermal decomposition of cobalt hydroxide synthesized from cobalt acetate, ammonium hydroxide and 10% glycerol. The cobalt oxide nanoparticles calcined at 450 °C were characterized by using XRD. The XRD confirms the crystallinity and crystal structure of the sample. It also shows that the diffraction peak are broadened which reveals the narrow size distribution of the cobalt oxide nanoparticles. In addition, the average grain size, lattice parameter values also calculated using XRD. The FT-IR analysis confirms the functional group presents in the cobalt oxide nanoparticles. The SEM image of cobalt oxide nanoparticles shows the nanosized agglomerated particles. The electrochemical detection of nitrobenzene (NB) by cobalt oxide nanoparticles was investigated by cyclic voltammetry. The result concludes that the cobalt oxide nanoparticles have higher activity for the detection of nitrobenzene.
55 citations
TL;DR: In this article, the electrochemical oxidation of pesticide, nitrobenzene (NB) as one kind of pesticide that is potentially dangerous and biorefractory, was studied by galvanostatic electrolysis using boron-doped diamond (BDD) as anode.
54 citations
TL;DR: The performance and mechanism of anaerobic treatment of nitrobenzene using the combination of Shewanella species and anthraquinone-2-sulfonate-modified polyurethane foam (Shewanella/AQS-PUF) were investigated and it was found that the bound EPS of She Swanella species could act as biocatalyst for nitro Benzene reduction and the addition of flavins enhanced its catalytic activity.
TL;DR: In this article, photo-catalytic N-alkylation of aniline by Au-TiO2 was reported, and the combined selectivities of mono-and dialkylated products were always in excess of 70% and dependent on the alkylating alcohol used.
TL;DR: In this paper, the catalysts were characterized by X-ray diffraction, high resolution transmission electron microscopy among others, and evaluated in the hydrogenation of nitrobenzene in a batch type reactor at 25°C.
Abstract: Recently, gold has been proposed as an active phase for the hydrogenation of nitro-arenes. This metal has been rarely used in hydrogenation reactions because gold does not possess hydrogen chemisorption capacity. However, small gold particles behave differently and they may be able to chemisorb hydrogen to same extent, leading to possible activity in hydrogenation reactions. This may provide an advantage because the reactions catalyzed by highly dispersed gold particles may be better controlled. In this work, TiO2 and SiO2 supported Au catalysts were prepared by the deposition–precipitation method using urea and NaOH to precipitate the metallic component at different temperatures and hydrogen pressures. The metal loading for all the catalysts was 1 wt%. The catalysts were characterized by X-ray diffraction, high resolution transmission electron microscopy among others. The catalysts were then evaluated in the hydrogenation of nitrobenzene in a batch type reactor at 25 °C. All the catalysts were active in the hydrogenation reaction and the major obtained product was aniline.
TL;DR: A new strategy was developed and applied in monitoring pH response and enzyme activity based on fluorescence emission red shift (FERS) of the conjugated polymer PPP-OR10 induced by the inner filter effect (IFE) of nitrobenzene derivatives, promising in applications in more complex conditions and a broader field.
Abstract: A new strategy was developed and applied in monitoring pH response and enzyme activity based on fluorescence emission red shift (FERS) of the conjugated polymer PPP-OR10 induced by the inner filter effect (IFE) of nitrobenzene derivatives. Neutral poly(p-phenylenes) functionalized with oligo(oxyethylene) side chains (PPP-OR10) was designed and synthesized by the Suzuki cross-coupling reaction. Nitrobenzene derivatives display different light absorption activities in the acidic or basic form due to adopting different electron-transition types. When environmental pH is higher than their pKa values, nitrobenzene derivatives exhibit strong absorbance around 400 nm, which is close to the maximal emission of polymer PPP-OR10. As a result, the maximal emission wavelength of PPP-OR10/nitrobenzene derivatives red shifts with the pH value increasing. Apparently, the IFE plays a very important role in this case. A new method has been designed that takes advantage of this pH-sensitive platform to sensor α-chymotrypsi...
TL;DR: In this paper, a 1%Ir/ZrO2 catalyst was used in the hydrogenation of aromatic meta-substituted nitrobenzene in liquid phase.
TL;DR: In this paper, a co-precipitation method was used to characterize the effect of hydrophobic organic contaminants (naphthalene, nitrobenzene, acetophenone) and hydrophilic contaminant (aniline) on DS−-Mg-Fe LDH.
TL;DR: In this article, the synthesis of azobenzene from nitrobenzene hydrogenation in the presence of a heterogeneous catalyst was studied and a detail reaction mechanism was proposed and a suitable kinetic model derived.
TL;DR: In this article, the effects of carbon-based solid acid type, Pt/C catalyst loading, hydrogen pressure and reaction temperature on nitrobenzene conversion and PAP selectivity were investigated.
TL;DR: EME on dried blood spot extracts were tested, and proved highly successful, showing that EME can be an effective way of preparing aqueous samples containing substantial amounts of an organic solvent.
TL;DR: A four-step model for nitrobenzene reduction by Fe(II) associated with iron oxides is proposed and it is proposed that magnetite>goethite>hematite>Fe(II)-humic acid complexes did not present reduction capability of nitro Benzene.
TL;DR: In this article, a case study reaction of nitrobenzenereduction was taken as the case study for this investigation, where Pt and Cu nanoparticles, supported by multiple wall carbonnanotubes, were taken as electrocatalysts and ethanolic and acidity-enhanced environments were studied as possible reaction media.
TL;DR: In this paper, a platelet SBA-15 with short and parallel channels and a conventional fiber SBA15 with long and curved pores were synthesized through hydrothermal routes.
TL;DR: In this article, a high efficient visible-light-induced photocatalytic hydrogenation of nitrobenzene to aniline in water was observed over a Bi2MoO6 photocatalyst under N2 atmosphere in the presence of (NH4)2C2O4 as a hole scavenger.
Abstract: Highly efficient visible-light-induced photocatalytic hydrogenation of nitrobenzene to aniline in water was observed over a Bi2MoO6 photocatalyst under N2 atmosphere in the presence of (NH4)2C2O4 as a hole scavenger. 100% of the nitrobenzene was converted and the selectivity of aniline was ∼97% after 20 min of visible light irradiation (λ ≥ 400 nm). The Bi2MoO6 photocatalyst showed good catalytic stability for the hydrogenation of nitrobenzene. Further experimental results revealed that both (NH4)2C2O4 and the N2 atmosphere were indispensable for the photocatalytic hydrogenation of nitrobenzene to aniline over the Bi2MoO6 photocatalyst. On the basis of the electron spin resonance analysis results, photoinduced electrons of the Bi2MoO6 photocatalyst were found to be the main active species for the hydrogenation of nitrobenzene. Moreover, a mechanism was proposed to explain the visible-light-induced photocatalytic hydrogenation of nitrobenzene to aniline over the Bi2MoO6 photocatalyst.
TL;DR: In this paper, the structural and textural properties of photocatalysts were investigated using X-ray powder diffraction and transmission electron microscopy to study the porosity, surface area and equivalent surface free energy of different Mg-Mn ferrites.
Abstract: MgxMn1-xFe2O4 (x = 00, 02, 04, 05, 06 08 and 10) spinel ferrite system was synthesized by the chemical co-precipitation route Subsequent characterization of synthesized Mg-Mn ferrites was carried out by X-ray powder diffraction and transmission electron microscopy to study the structural and textural properties of photocatalysts Porosity, surface area and equivalent surface free energy of different Mg-Mn ferrite photocatalysts were calculated The photocatalytic activity of synthesized photocatalysts was evaluated by degradation of nitrobenzene in aqueous medium under ultraviolet light irradiation The results demonstrated that the percentage degradation of nitrobenzene was decreased with increase in Mg concentration (x) from x = 00 05 and further increase in concentration from x = 06 10 results increase in percentage degradation of NB This dissimilarity in the percentage degradation of NB may be due to the change in grain morphology, optical energy band gap, role played by d-electrons and porosity as a function of Mg-substitution for Mn2+ in the system The percentage degradation was further confirmed by chemical oxygen demand (COD) analysis
TL;DR: Azobenzene, azoxybenzene and acetanilide were observed in NB and AN mixtures degradation, the first report confirming the by-products of NB and An mixture biodegradation by a cold-tolerant microbial consortium.
TL;DR: In this paper, the first examples of metal-catalyzed sp2-sp cross-coupling reactions involving C-F bond activation were described, and a palladium-calyzed Sonogashira type process was described.
TL;DR: In this paper, the photocatalytic reduction of nitrobenzene (NB) under UV or visible light illumination was evaluated by X-ray powder diffraction analysis, UV-visible diffuse reflectance spectroscopy, scanning electron microscopy, and differential thermal analysis.
TL;DR: In this paper, two Cu(II) complexes were synthesized and characterized by elemental analysis, IR, single crystal X-ray crystallography and thermal analysis, and structural determination reveals that complex 1 is dinuclear, while complex 2 is a 1D polymeric chain built by a bridging cbtc ligand.
TL;DR: In this paper, a water-compatible hyper-cross-linked resin functionalized with amino-group (GQ-04) was synthesized to remove salicylic acid (SA) in aqueous solution.
Abstract: On account of the high toxicity of nitrobenzene, 1,2-dichloroethane was used as solvent A novel water-compatible hyper-cross-linked resin functionalized with amino-group (denoted as GQ-04) was synthesized to remove salicylic acid (SA) in aqueous solution The maximum adsorption capacity of SA onto GQ-04 was observed at pH of 188 The adsorption capacity increased with the increasing salt concentration The adsorption kinetic data obeyed the pseudo-second-order rate equation and the adsorption isotherms can be characterized by Freundlich model The intraparticle diffusion was the main rate-controlling step The saturated adsorption quantity of SA was up to 1199 mg·mL-1 according to the dynamic adsorption at 293 K The resin could be regenerated by the 6 BV mixed solution of 80% ethanol and 05 mol/L NaOH The size matching and hydrogen bonding between GQ-04 and SA and the micropore structure resulted in the larger adsorption capacity in comparison with XAD-4 and H103 resin © 2012 Wiley Periodicals, Inc J Appl Polym Sci, 2013
TL;DR: The sulfonated condensed polynuclear aromatic (S-COPNA(PR)) resin (PR = pyrene) was used for the synthesis of cyclohexyl acetate and oleyl acetate in water.
Abstract: Oxidative coupling polymerization of naphthalene, anthracene, and pyrene with FeCl3 in nitrobenzene under nitrogen gave polynaphthalene (PNP), polyanthracene (PAT), and polypyrene (PPR) in good yields, respectively. PNP, PAT, and PPR were transformed into sulfonated PNP (S-PNP), S-PAT, and S-PPR by the treatment with chlorosulfonic acid in dichloromethane at 25°C for 24 h under nitrogen, respectively. The activities of S-PPR were higher than those of S-PNP and S-PAT. For the hydrolysis of cyclohexyl acetate and oleyl acetate in water, activities of S-PPR, S-PAT, and S-PNP were considerably higher than those of the other conventional solid acids. Rate constants of S-PPR were 2.8 and 11.7 times larger than those of the sulfonated condensed polynuclear aromatic (S-COPNA(PR)) resin (PR = pyrene) for the hydrolysis of cyclohexyl acetate and oleyl acetate, respectively. S-PPR, S-PAT, and S-PNP were reused without significant loss of activities. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013