scholarly journals Highly Selective pH-Dependent Ozonation of Cyclohexane over Mn/γ-Al2O3 Catalysts at Ambient Reaction Conditions

Catalysts ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 958 ◽  
Author(s):  
Siphumelele Thandokwazi Mkhondwane ◽  
Viswanadha Srirama Rajasekhar Pullabhotla
Keyword(s):  
Electron Microscopy ◽  
Reaction Time ◽  
Catalytic Performance ◽  
Gamma Alumina ◽  
Reaction Conditions ◽  
X Ray ◽  
Ozonation Time ◽  
Ft Ir ◽  
Percentage Conversion ◽  
Ft Ir Spectroscopy

The selective oxidation of cyclohexane to a mixture of cyclohexanol and cyclohexanone (KA oil) is one of the imperative reactions in industrial processes. In this study, the catalytic performance of manganese-supported gamma alumina (Mn/γ-Al2O3) catalysts is investigated in the selective oxidation of cyclohexane at ambient conditions using ozone. The catalysts were prepared by the wet impregnation method, and their physio-chemical properties were studied by Fourier Transform Infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) spectroscopy, Scanning Electron Microscopy-Energy Dispersive X-ray spectroscopy (SEM-EDX), Transmission Electron Microscopy (TEM), Inductively Coupled Plasma (ICP) spectroscopy, and Brunauer Emmett and Teller (BET). The reaction conditions were optimised considering various parameters such as reaction time, pH, and various percentages of the manganese supported in gamma alumina. The oxidation of cyclohexane was conducted in an impinger reactor unit at pH 3, 7, and 11 for 1 h of ozonation time. The aliquots were collected after 30 min and 1 h of ozonation time and analysed with GC-MS and FT-IR spectroscopy. The 2.5% Mn/γ-Al2O3 catalyst exhibited a significantly enhanced catalytic performance at pH 3 and 7 with a percentage conversion of 9% and 15% at pH 3 and 7, respectively, after 30 min of ozonation time. However, after 1 h of ozonation time, the percentage conversions were increased to 23% and 29% at pH 3 and 7, respectively. At pH 11, 5% Mn/γ-Al2O3 exhibit high catalytic performance with a percentage conversion of 19% and 31% after 30 minutes and 1 h of ozonation time, respectively. The percentage selectivity obtained is 100% toward KA oil and/or cyclohexanone depending on pH and reaction time.

scholarly journals Synthesis of amine-epoxy based polymers and their potential application in the remediation of selected organic dyes from synthetic effluents

2017 ◽  
Author(s):  
◽  
Sharista Raghunath
Keyword(s):  
Electron Microscopy ◽  
Catalytic Activity ◽  
Ir Spectroscopy ◽  
1H Nmr Spectroscopy ◽  
Organic Dyes ◽  
Synthetic Dyes ◽  
X Ray ◽  
Dye Reduction ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

The presence of dyes in effluent poses various environmental as well as health hazards for many organisms. Although various remediation strategies have been implemented to reduce their effect, dyes still manage to infiltrate into the environment and hence new strategies are required to address some of the problems. This study investigated the innovation of two cationic water-soluble polymers viz., Proline-Epichlorohydrin-Ethylenediamine Polymer (PEP) and Thiazolidine-Epichlorohydrin-Ethylenediamine Polymer (TEP) that were used to remediate selected synthetic dyes from synthetic effluent by adsorption and dye reduction. Both polymers were synthesized using monomers of a secondary amine, epichlorohydrin and ethylenediamine and were subsequently characterized and modified and their remediation potential studied. In the first study, PEP was synthesized and characterized by 1H-NMR Spectroscopy, FT-IR Spectroscopy, dynamic light scattering, and thermogravimetric analysis (TGA). Thereafter PEP was modified with bentonite clay, by simple mixing of the reactants, to form a Proline-Epichlorohydrin-Ethylenediamine Polymer-bentonite composite (PRO-BEN); it was characterized by FT-IR Spectroscopy, scanning electron microscopy (SEM)/ energy dispersive X-ray spectroscopy (EDX), dynamic light scattering (DLS), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Adsorption studies were then undertaken with a synthetic effluent containing three textile dyes, viz., Reactive Blue 222 (RB 222), Reactive Red 195 (RR 195) and Reactive Yellow (RY 145). Various conditions were investigated including pH of the solution, temperature, sodium chloride concentration, initial dye concentration and the dosage of adsorbent used. The experimental data for all dyes followed a Langmuir isotherm. The adsorption process was found to be pseudo-second order. According to the thermodynamic parameters, the adsorption of the dyes was classified as physisorption and the reaction was spontaneous and exothermic. The data were also compared using studies with alumina as an adsorbent. Results showed that PRO-BEN exhibited better absorptivity and desorption than alumina making its use a better recyclable remediation strategy for the removal of organic dyes in wastewater treatment plants. In the second study, TEP was synthesized and then characterized by FT-IR Spectroscopy, 1H-NMR Spectroscopy, TGA and DLS. Thereafter, TEP was used to prepare TEP capped gold nanoparticles (TEP-AuNPs). Herein, two methods were investigated: the Turkevich method and an adaptation of the Turkevich method using bagasse extract. The TEP-AuNPs was characterized by FT-IR Spectroscopy, SEM, EDX, DLS and TEM. Thereafter the reduction of each of Allura Red, Congo Red and Methylene Blue was investigated with the TEP-AuNPs for its catalytic activity toward dye reduction. This study showed that the batch of AuNPs prepared by the Turkevich method had higher rates of dye reduction compared with AuNPs prepared using bagasse extract. Also the quantity of TEP used as capping agent greatly influenced the size, shape and surface charge of the nanoparticles as well as their catalytic performance: the Vroman effect explained this behavior of the TEP-AuNPs. It was finally concluded that whilst PRO-BEN, in the first study, showed excellent dye remediation properties, the second study on TEP-AuNPs showed good catalytic activity for the reduction of selected dyes, however, it was more effective at lower polymer concentration. Finally, both materials displayed good potential for the clean-up of selected synthetic dyes from synthetic effluents.

Synthesis of Fe 3+-Dopped PANI Conductive Nanomaterials via Interfacial Polymerization

2011 ◽  
Vol 239-242 ◽  
pp. 2839-2842
Author(s):  
Hong Mei Mu ◽  
Peng Fei ◽  
Bi Tao Su ◽  
Zi Qiang Lei
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fourier Transform ◽  
Ir Spectroscopy ◽  
Interfacial Polymerization ◽  
X Ray ◽  
Transmission Electron ◽  
Ft Ir ◽  
Conductive Nanomaterials ◽  
Ft Ir Spectroscopy

A series of Fe3+-dopped polyaniline (Fe3+/PANI) nanomaterials with different morphologies and a higher conductivity were successfully synthesized using a simple and static interfacial polymerization by using FeCl3 as both oxidant catalyst and dopant. The effect of surfactants CTAB and SDS and the concentration of FeCl3 on the morphology and conductivity of Fe3+/PANI nanomaterial were investigated. The samples were characterized by Transmission Electron Microscopy (TEM), SDY-4 probes conductivity meter, X-ray Diffractometry (XRD), Energy dispersive spectroscopy (EDS) and Fourier transform infrared (FT-IR) spectroscopy techniques. TEM’s results showed that their morphologies changed with the type of the surfactant and the concentration of FeCl3. Introducing surfactants CTAB and SDS into Fe3+/PANI remarkably improved the conductivity of the material. The conductivities of CTAB/Fe3+/PANI and SDS /Fe3+/PANI nanomaterials were respectively about 4.8×10-2 and 1.3×10-2 S/cm while the conductivity of Fe3+/PANI was found to be 1.5×10-4 S/cm. The different morphology and high conductivity may be ascribed to the mutual effects of the surfactant and oxidant.

Synthesis and Characterization of HgSe Nanostructure Using a Novel Precursor

2013 ◽  
Vol 32 (2) ◽  
pp. 157-162 ◽  
Author(s):  
Mahdiyeh Esmaeili-Zare ◽  
Masoud Salavati-Niasari ◽  
Davood Ghanbari
Keyword(s):  
Electron Microscopy ◽  
Synthesis And Characterization ◽  
Sonochemical Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Mercury Selenide ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

AbstractMercury selenide nanostructures were synthesized from the reaction of N, N′-bis(salicylidene)propane-1,3-diamine mercury complex, (Hg(Salpn)) as a novel precursor, via sonochemical method. The effect of different surfactant on the morphology and particle size of the products was investigated. Products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy and X-ray energy dispersive spectroscopy (EDS).

Microstructural of Cr/MWCNT Composites and its Catalysis in Synthesis of Biodiesel

2012 ◽  
Vol 455-456 ◽  
pp. 1053-1059
Author(s):  
Xue Hai Fan ◽  
Guo Min Xiao
Keyword(s):  
Electron Microscopy ◽  
Potassium Dichromate ◽  
Catalytic Performance ◽  
Impregnation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Multi Walled Carbon Nanotubes ◽  
Ft Ir ◽  
Walled Carbon Nanotubes

Multi-walled carbon nanotubes (MWCNTs), potassium dichromate (K2Cr2O7) and sulphuric acid were used for the preparation of Cr/MWCNT composite by impregnation method. The composites were comprehensively characterized by transmission electron microscopy （TEM），energy dispersive X-ray analysis (EDX), infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and thermal gravity analysis (TGA). Due to its unique electrical and structural properties, this composite was applied to the synthesis of biodiesel (FAME) as a catalyst, showing effectively catalytic performance.

scholarly journals Halloysite Nanotubes Modified by Chitosan as an Efficient and Eco-Friendly Heterogeneous Nanocatalyst for the Synthesis of Heterocyclic Compounds

Proceedings ◽  
2019 ◽  
Vol 41 (1) ◽  
pp. 59
Author(s):  
Diana Fallah Jelodar ◽  
Zoleikha Hajizadeh ◽  
Ali Maleki
Keyword(s):  
Fourier Transform ◽  
Ir Spectroscopy ◽  
Heterocyclic Compounds ◽  
High Efficiency ◽  
Halloysite Nanotubes ◽  
Reaction Conditions ◽  
X Ray ◽  
Recoverable Catalyst ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

In this study, halloysite nanotubes (HNTs) are modified by chitosan as a natural cationic amino polysaccharide. Halloysite nanotubes/chitosan (HNTs/Chit) were characterized by Fourier transform infrared (FT-IR) spectroscopy and energy dispersive X-ray (EDX) analysis. Also, its performance as a heterogeneous catalyst was investigated in the synthesis of pyranopyrazole derivatives. Being a reusable and easily recoverable catalyst, eco-friendliness, high efficiency, and mild reaction conditions are some advantages of the present work.

Assembling of 12-Tungstophosphoric Acid into Amino-Modified SBA-15 and its Catalytic Performance

2012 ◽  
Vol 465 ◽  
pp. 224-228 ◽  
Author(s):  
Hong Qi Guo ◽  
Gong Yan ◽  
Ming Qing Chen ◽  
Shi Rong Liu
Keyword(s):  
Catalytic Performance ◽  
Tungstophosphoric Acid ◽  
Esterification Reaction ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Catalytic Activities ◽  
Ft Ir ◽  
Adsorption Desorption ◽  
Ft Ir Spectroscopy

12-tungstophosphoric acid was supported on amine-modified SBA-15 by impregnation. The structure and properties of the catalyst were characterized by FT-IR spectroscopy, X-ray diffraction, N2 adsorption-desorption, TEM,Raman spectra and NH3–TPD technology.the result confirmed the mesostructure for SBA-15 and the Keggin structure of the heteropolyanions was preserved. The tungstophosphoric acid can disperse in the pore of the support SBA-15/NH2, but the acidity of the catalyst reduced. The catalytic activities of the catalysts were evaluated for the esterification reaction of ethyl acetoacetate and ethylene glycol .and the catalysts supported on amine-modified SBA-15 show excellent reusability and selectivity.

scholarly journals Aegle marmelosMediated Green Synthesis of Different Nanostructured Metal Hexacyanoferrates: Activity against Photodegradation of Harmful Organic Dyes

Scientifica ◽  
2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Vidhisha Jassal ◽  
Uma Shanker ◽  
B. S. Kaith
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Degradation ◽  
Organic Dyes ◽  
Degradation Process ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
X Ray ◽  
Transmission Electron ◽  
Ft Ir ◽  
Metal Hexacyanoferrate

Prussian blue analogue potassium metal hexacyanoferrate (KMHCF) nanoparticles Fe4[Fe(CN)6]3(FeHCF), K2Cu3[Fe(CN)6]2(KCuHCF), K2Ni[Fe(CN)6]·3H2O (KNiHCF), and K2Co[Fe(CN)6] (KCoHCF) have been synthesized using plant based biosurfactantAegle marmelos(Bael) and water as a green solvent. It must be emphasized here that no harmful reagent or solvent was used throughout the study. Plant extracts are easily biodegradable and therefore do not cause any harm to the environment. Hence, the proposed method of synthesis of various KMHCF nanoparticles followed a green path. The synthesized nanoparticles were characterized by powder X-ray diffraction (PXRD), Field-Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM), and Fourier Transform Infrared Spectroscopy (FT-IR). MHCF nanoparticles were used for the photocatalytic degradation of toxic dyes like Malachite Green (MG), Eriochrome Black T (EBT), Methyl Orange (MO), and Methylene Blue (MB). Under optimized reaction conditions, maximum photocatalytic degradation was achieved in case of KCuHCF nanoparticles mediated degradation process (MG: 96.06%, EBT: 83.03%, MB: 94.72%, and MO: 63.71%) followed by KNiHCF (MG: 95%, EBT: 80.32%, MB: 91.35%, and MO: 59.42%), KCoHCF (MG: 91.45%, EBT: 78.84%, MB: 89.28%, and MO: 58.20%).

scholarly journals Microwave-assisted synthesis, characterization and photoluminescence of shuttle-like BaMoO4 microstructure

2015 ◽  
Vol 33 (3) ◽  
pp. 537-540 ◽  
Author(s):  
Anukorn Phuruangrat ◽  
Budsabong Kuntalue ◽  
Titipun Thongtem ◽  
Somchai Thongtem
Keyword(s):  
Electron Microscopy ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Assisted ◽  
Transmission Electron ◽  
Ft Ir ◽  
Xrd Patterns ◽  
Scanning Electron ◽  
Ft Ir Spectroscopy

Abstract Shuttle-like BaMoO4 microstructure has been successfully synthesized from Ba(N03)2·4H20 and Na2MoO4·2H2O as starting materials in ethylene glycol solvent containing 20 mL 5 M NaOH by microwave radiation at 180 W for 30 min. The as- synthesized BaMoO4 product was characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectrophotometry, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and photolumines­cence (PL) spectroscopy. XRD patterns revealed that the products was tetragonal BaMoO4 phase. SEM and TEM characteriza­tion showed that the product had a shuttle-like BaMoO4 microstructure. PL of the shuttle-like BaMoO4 microstructure showed a maximum emission at 466 nm excited by 280 nm wavelength.

Facile Hydrothermal Synthesis of CoSO4ċH2O Nanoparticles and Barite Microcubes from Novel Precursors

2012 ◽  
Vol 31 (6) ◽  
pp. 711-715 ◽  
Author(s):  
Azam Sobhani ◽  
Masoud Salavati-Niasari
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Thermal Decomposition ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Ft Ir ◽  
Scanning Electron ◽  
Ft Ir Spectroscopy

AbstractCoSO4ċH2O nanoparticles and barite (BaSO4) microcubes have been prepared by hydrothermal decomposition of new precursors [Co(tsc)2]Cl2 and [Ba(tsc)2]Cl2 (tsc =  thiosemicarbazide), respectively. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR) spectroscopy. As a comparison between two methods, thermal decomposition of novel precursors in high temperature boiling organic solvents were examined.

Delamination of Kaolinite by Intercalation of Urea Using Milling

2017 ◽  
Vol 888 ◽  
pp. 136-140 ◽  
Author(s):  
Suzi Salwah Jikan ◽  
Nur Azam Badarulzaman ◽  
Shehu Yahaya ◽  
Ajiya Dahiru Adamu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Fourier Transform ◽  
Ir Spectroscopy ◽  
Powder Diffraction ◽  
Basal Spacing ◽  
X Ray ◽  
Ft Ir ◽  
Scanning Electron ◽  
Ft Ir Spectroscopy

The effect of milling on structure of kaolinite-urea intercalates were studied. Untreated and treated kaolinite samples were examined by Field scanning electron microscopy (FESEM), X-ray powder diffraction (XRPD) and Fourier transform infrared (FT-IR) spectroscopy. The basal spacing of kaolinite measured by X-ray powder diffraction (XRPD) increased from 1.02 to 3.62 nm after intercalation by urea. Significantly, nature of intercalation was reached through formation of hydrogen bonds between urea and both Si-O and AlOH groups of the interlayer surface of kaolinite.

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