Preparation and Characterization of Ni-Modified Fe-Mo and Catalytic Selective Oxidation of p-Xylene

2012 ◽  
Vol 557-559 ◽  
pp. 1501-1504 ◽  
Author(s):  
Zu Zeng Qin ◽  
Zi Li Liu ◽  
Yan Bin Liu ◽  
Rui Wen Liu
Keyword(s):  
Photoelectron Spectrum ◽  
Sol Gel ◽  
Catalytic Performance ◽  
Ni Catalyst ◽  
Temperature Programmed Reduction ◽  
X Ray ◽  
Mo Catalyst ◽  
Ft Ir ◽  
Temperature Programmed

The preparation of the Fe-Mo-Ni catalyst using the sol-gel method was investigated. In addition, the catalytic selective oxidations of p-xylene (PX) to terephthalaldehyde (TPAL) on the Fe-Mo-Ni catalyst were also investigated. The catalysts were characterized using thermal analysis, H2-temperature programmed reduction (H2-TPR), Fourier transform infrared spectra (FT-IR), and X-ray photoelectron spectrum (XPS). The additional of Ni improves the catalytic activity of the Fe-Mo catalyst on selective oxidations of PX to TPAL. The optimal additive amount of Ni is 5%. XPS analysis shows that the introduction of Ni changes the internal structure of the Fe-Mo catalyst improves catalytic performance.

scholarly journals Hydrogenative Cyclization of Levulinic Acid to γ-Valerolactone with Methanol and Ni-Fe Bimetallic Catalysts

Catalysts ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1096
Author(s):  
Ligang Luo ◽  
Xiao Han ◽  
Qin Zeng
Keyword(s):  
Photoelectron Spectroscopy ◽  
Levulinic Acid ◽  
Hydrogen Donor ◽  
Effect Of Temperature ◽  
X Ray ◽  
Transmission Electron ◽  
Ft Ir ◽  
Temperature Programmed

A series of Ni-Fe/SBA-15 catalysts was prepared and tested for the catalytic hydrogenation of levulinic acid to γ-valerolactone, adopting methanol as the only hydrogen donor, and investigating the synergism between Fe and Ni, both supported on SBA-15, towards this reaction. The characterization of the synthesized catalysts was carried out by XRD (X-ray powder diffraction), TEM (transmission electron microscopy), H2-TPD (hydrogen temperature-programmed desorption), XPS (X-ray photoelectron spectroscopy), and in situ FT-IR (Fourier transform–infrared spectroscopy) techniques. H2-TPD and XPS results have shown that electron transfer occurs from Fe to Ni, which is helpful both for the activation of the C=O bond and for the dissociative activation of H2 molecules, also in agreement with the results of the in situ FT-IR spectroscopy. The effect of temperature and reaction time on γ-valerolactone production was also investigated, identifying the best reaction conditions at 200 °C and 180 min, allowing for the complete conversion of levulinic acid and the complete selectivity to γ-valerolactone. Moreover, methanol was identified as an efficient hydrogen donor, if used in combination with the Ni-Fe/SBA-15 catalyst. The obtained results are promising, especially if compared with those obtained with the traditional and more expensive molecular hydrogen and noble-based catalysts.

Mesoporous phosphated and sulphated silica as solid acid catalysts for glycerol acetylation

2014 ◽  
Vol 68 (9) ◽  
Author(s):  
Khadijeh Ghoreishi ◽  
Nilofar Asim ◽  
Mohd Yarmo ◽  
Mohd Samsudin
Keyword(s):  
Photoelectron Spectroscopy ◽  
Solid Acid ◽  
Sol Gel ◽  
Acid Catalysts ◽  
X Ray ◽  
Bet Method ◽  
Ft Ir ◽  
Temperature Programmed ◽  
Catalyst Acidity ◽  
Glycerol Esterification

AbstractSulphate- and phosphate-loaded silicas were synthesised using the sol-gel method with different sulphate and phosphate loadings. These catalysts were characterised using Fourier transform infrared spectroscopy (FT-IR), the Brunauer-Emmett-Teller (BET) method and X-ray photoelectron spectroscopy (XPS). Acidity was measured using the temperature-programmed desorption of ammonia (TPD-NH3) method. The results showed that glycerol esterification with acetic acid conversion decreased as follows: α(H2SO4) (100 %) > α(H3PO4) (99 %) > α(silica loaded with 20 % sulphuric acid) (SS-20; 98 %) > α(silica loaded with 20 % phosphoric acid) (PS-20; 83 %). These studies suggest that the solid acid catalytic activity in the esterification of glycerol is highly dependent on catalyst acidity strength, pore size and surface area.

scholarly journals Characterization of Modified Magnetite Nanoparticles for Albumin Immobilization

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
A. K. Bordbar ◽  
A. A. Rastegari ◽  
R. Amiri ◽  
E. Ranjbakhsh ◽  
M. Abbasi ◽  
...  
Keyword(s):  
Sol Gel ◽  
Xrd Analysis ◽  
Covalent Immobilization ◽  
Initial Value ◽  
X Ray ◽  
Buffer Solutions ◽  
Transmission Electron ◽  
Ft Ir ◽  
Chemical Coprecipitation Method

Magnetite Fe3O4 nanoparticles (NPs) were prepared by chemical coprecipitation method. Silica-coated magnetite NPs were prepared by sol-gel reaction, subsequently coated with 3-aminopropyltriethoxysilane (APTES) via silanization reaction, and then were activated with 2,4,6-trichloro-1,3,5-triazine (TCT) and covalently immobilized with bovine serum albumin (BSA). The size and structure of the particles were characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD), and dynamic light scattering (DLS) techniques. The immobilization was confirmed by Fourier transform infrared spectroscopy (FT-IR). XRD analysis showed that the binding process has not done any phase change to Fe3O4. The immobilization time for this process was 4 h and the amount of immobilized BSA for the initial value of 1.05 mg BSA was about 120 mg/gr nanoparticles. Also, the influences of three different buffer solutions and ionic strength on covalent immobilization were evaluated.

Study of Preparation, Characterization and Temperature-Programmed Reduction of NiO-ZnO Binary Materials

2013 ◽  
Vol 664 ◽  
pp. 515-520
Author(s):  
Chih Wei Tang ◽  
Jiunn Jer Hwang ◽  
Shie Hsiung Lin ◽  
Chin Chun Chung
Keyword(s):  
Weight Percent ◽  
Precipitation Method ◽  
Temperature Programmed Reduction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surface Areas ◽  
Temperature Programmed ◽  
Co Precipitation ◽  
Adsorption Desorption

The NiO-ZnO binary materials had been prepared by co-precipitation method. The weight percent of nickel of NiO-ZnO materials were 5, 10 and 20; they were pretreated under air at temperature of 300, 500 and 700°C, respectively. The characterization of NiO-ZnO materials were the thermal gravity analysis(TGA), X-ray diffraction(XRD), N2 adsorption-desorption at 77K, scaning electron microscope(SEM) and temperature-programmed reduction(TPR). The results revealed that surface areas of NiO-ZnO materials order from large to small were 20NiZn(OH)x(66 m2·g-1) > 10NiZn(OH)x(34 m2·g-1) > 5NiZn(OH)x(9 m2·g-1) after being calcined at the temperature of 500°C. Further, NiO-ZnO materials had two main reductive peaks at 390-415°C and 560-657°C, respectively. In all NiO-ZnO materials, 20NiZn(OH)x-C500 material had the highest surface area and the best interaction between NiO and ZnO.

Reduction Behaviour of WO3 to W under Carbon Monoxide Atmosphere

2016 ◽  
Vol 840 ◽  
pp. 305-308
Author(s):  
Fairous Salleh ◽  
Tengku Shafazila Tengku Saharuddin ◽  
Alinda Samsuri ◽  
Rizafizah Othaman ◽  
Mohamed Wahab Mohamed Hisham ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Temperature Programmed Reduction ◽  
X Ray Diffraction ◽  
Reduction Behavior ◽  
X Ray ◽  
Isothermal Reduction ◽  
Reduction Behaviour ◽  
Temperature Programmed ◽  
Metal Phases

The reduction behaviour of tungsten oxide has been studied by using temperature programmed reduction (TPR) and X-ray diffraction (XRD). The reduction behavior were examine by nonisothermal reduction up to 900 oC then continued with isothermal reduction at 900 oC for 45 min time under (40% v/v) carbon monoxide in nitrogen (CO in N2) atmosphere. The TPR signal clearly shows one peak attributed to formation of suboxide W18O49 (more) and WO2 (less) observed at 80 min. The reduction product was investigated by varying the holding reaction time. Based on the characterization of the reduction products by using XRD, it was found that, nonisothermal reduction of WO3 at temperature 900 oC partially converted to some W18O49 and WO2 phases. However, after increased the reaction holding time for 45 min, WO3 phases disappeared and converted to WO2 and W metal phases. It is obviously shows that by hold the reduction time could improve the reducibility of the sample oxide. Furthermore, it is suggested that reduction by using CO as reducing agent follows the consecutives steps WO3 → WO2.92 → W18O49 → WO2 → W.

Preparation and Characterization of TiO2 Nanoparticle with SiO2 Shell

2011 ◽  
Vol 233-235 ◽  
pp. 1188-1191
Author(s):  
Hong Cai ◽  
Yan Chen ◽  
Yun Ying Wu
Keyword(s):  
Photoelectron Spectroscopy ◽  
Photocatalytic Performance ◽  
Sol Gel ◽  
Chemical Components ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Bonding Phase ◽  
Hydrolysis Of

Nano-TiO2 particles were prepared by sol-gel method, of which the surfaces were coated by SiO2. The coating was achieved by the hydrolysis of sodium silicate (Na2SiO3) in ammonium chloride (NH4Cl). The surface bonding, phase constitution and chemical components of the samples were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction(XRD) and X-ray photoelectron spectroscopy (XPS). The mechanism of the SiO2 coating process onto TiO2 surface was analyzed. Results show that SiO2 particles were immobilized on the TiO2 surface via Ti—O—Si bondings, which formed at the interface. The SiO2 layer on TiO2 surface was amorphous, the photocatalytic performance was decreased of the TiO2 while its stability was enhanced after surface modification.

scholarly journals Preparation and Characterization of SnO2 Nanoparticles for Antibacterial Properties

2020 ◽  
pp. 1-5
Author(s):  
Thoker Bilal Ahmad ◽  
Ahmad Bhat Asif ◽  
wani Atif Khurshid ◽  
Ayoub Kaloo Masood ◽  
Shergojri Gulzar Ahmad
Keyword(s):  
Tin Oxide ◽  
Micrococcus Luteus ◽  
Sno2 Nanoparticles ◽  
Sol Gel ◽  
Antibacterial Properties ◽  
Nano Particles ◽  
X Ray ◽  
Search Engine Marketing ◽  
Ft Ir

To investigate morphological, optical and antibacterial properties of SnO2 nanoparticles which are synthesized by using an easy and affordable Sol-Gel method. By using various techniques such as XRD (X-ray Powder Diffraction), FT-IR (Fourier Transform Infrared), UV-Vis, PL, SEM (Search Engine Marketing), EDAX (Energy Dispersive X-Ray Analysis), the structural, optical, composition of elements and the size of the SnO2 nanoparticles (NPs) has been discussed. The variation in properties of SnO2 as synthesized and at annealing temperatures has also been discussed. Size of tin oxide Nano particles from XRD is found in the range of 9-10 nm, and the lattice parameters about a=b=4.73060A, c=3.690A. From UV-Vis it is found that the band gap of tin oxide decreases as we increase the temperature. Active efficiency of SnO2 NPs has been tested on Gram negative (E.coli) and gram positive (Micrococcus luteus) bacteria on the growth of pure culture using zone inhibition method.

scholarly journals Preparation of Stellerite Loading Titanium Dioxide Photocatalyst and Its Catalytic Performance on Methyl Orange

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Hua Chen ◽  
Jianhua Wang ◽  
Huajun Wang ◽  
Fei Yang ◽  
Jia-nan Zhou ◽  
...  
Keyword(s):  
Surface Area ◽  
Sol Gel ◽  
Catalytic Performance ◽  
Bet Surface Area ◽  
X Ray Diffraction ◽  
Photocatalytic Ability ◽  
X Ray ◽  
Composite Photocatalysts ◽  
Ft Ir ◽  
Better Than

TiO2/stellerite composite photocatalysts were prepared by dispersing TiO2 onto the surface of HCl, NaOH, or NaCl treated stellerite using a sol-gel method. The materials were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR), BET surface area analysis, and X-ray diffraction (XRD). HCl and NaCl modification result in the promotion of the pore formation at the stellerite surfaces and induced the microscopic changes, while the surface morphology and structure of the stellerite were almost ruined by NaOH modification. Supported TiO2 calcinated at 200°C presented anatase structure. The photocatalytic degradation activities of TiO2 loaded HCl and NaCl modified stellerite were better than that of natural stellerite, accompanied with increasing specific surface area. On the contrary, NaOH modification induced the loss of photocatalytic ability of composite due to the generation of silicates.

Preparation and Characterization of Pr2Ti2O7 by Sol-Gel Process

2017 ◽  
Vol 748 ◽  
pp. 413-417
Author(s):  
Chun Yu Long ◽  
Fang Fang Peng ◽  
Min Min Jin ◽  
Pei Song Tang ◽  
Hai Feng Chen
Keyword(s):  
Methyl Orange ◽  
Single Phase ◽  
Raw Materials ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Illumination Time ◽  
X Ray ◽  
Sol Gel Process ◽  
Ft Ir

Using Pr (NO3)3, butyl titanate, ethylene glycol and citric acid as main raw materials, praseodymium titanate (Pr2Ti2O7) was prepared by the sol-gel process. The samples were characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), thermal gravity-differential thermal analysis (TG-DTA), diffuse-reflection spectra (DRS) and Fourier transform infrared (FT-IR). The effect of different calcination temperature and illumination time on the photocatalytic properties of Pr2Ti2O7 was investigated. It was found that the single phase Pr2Ti2O7 could be obtained through sol-gel process and calcination at 1000 °C. The Pr2Ti2O7 samples calcination at 1000 °C were uniform , and the resulting product had a particle size of 200 nm and an optical band gap of 3.26 eV. Under ultraviolet light, the degradation of methyl orange arrived to 80.11% after 180 min of photocatalytic reaction. The Pr2Ti2O7 samples showed good photocatalytic activity for decomposition of methyl orange.

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