Catalytic Transfer Hydrogenolysis of 2-Phenyl-2-Propanol with Pd/C and Formic Acid

2011 ◽  
Vol 287-290 ◽  
pp. 1749-1752 ◽  
Author(s):  
Jian Feng ◽  
Wei Xiong ◽  
Yun Jia ◽  
Jin Bo Wang ◽  
De Rong Liu ◽  
...  
Keyword(s):  
Formic Acid ◽  
Inductively Coupled Plasma ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
New Approach ◽  
Inductively Coupled ◽  
Transmission Electron ◽  
Catalytic Transfer ◽  
Adsorption Desorption

The catalytic transfer hydrogenolysis of 2-phenyl-2-propanol was studied over Pd/C catalyst, using formic acid and formate salts as hydrogen donors. The Pd/C catalyst was characterized by powder X-ray diffraction (XRD), inductively coupled plasma (ICP), N2 adsorption/desorption and transmission electron microscopy (TEM). The effects of hydrogen donor, molar ratio of formic acid to 2-phenyl-2-propanol and water content were evaluated. Under mild reaction conditions (80 °C, 2h), 2-phenyl-2-propanol can be hydrogenolyzed to isopropylbenzene with very high selectivity (96.5%) and high conversion (92.8%) in the presence of Pd/C and formic acid. From the viewpoint of environmental friendly principles, this study may open the way to a new approach for the production of propylene oxide.

scholarly journals A study concerning the pretreatment of CNTs and its influence on the performance of NIB/CNTs amorphous catalyst

2006 ◽  
Vol 71 (11) ◽  
pp. 1153-1160 ◽  
Author(s):  
Chang Hu-Yuan ◽  
Feng Li ◽  
Li. Hua ◽  
Bin Zhang
Keyword(s):  
Selective Hydrogenation ◽  
Inductively Coupled Plasma ◽  
Acid Treatment ◽  
Chemical Reduction ◽  
X Ray Diffraction ◽  
Chemical Reduction Method ◽  
X Ray ◽  
Inductively Coupled ◽  
Selective Hydrogenation Of Acetylene ◽  
Transmission Electron

As prepared carbon nanotubes were pretreated with nitric acid (CNTs-HNO3) or ammonia (CNTs-NH3). Fourier transform infrared spectroscopy (FTIR) measurements showed that the surface of the nanotubes was functionalized with carboxylic and hydroxyl functional groups after the acid treatment and that basic groups containing nitrogen, such as N-H and C-N, were introduced to the surface of the nanotubes after the ammonia treatment. X-Ray diffraction analysis implied that the nickel residue in the CNTs was effectively removed by acid treatment. However, the nickel residue was only partially eliminated by ammonia pretreatment. NiB amorphous catalysts supported on CNTs-HNO3 and CNTs-NH3 were prepared by the impregnation-chemical reduction method and characterized by transmission electron microscopy (TEM), as well as inductively coupled plasma (ICP) spectroscopy and studied in the selective hydrogenation of acetylene. TEM measurements showed that a high density NiB particles of about 9 nm were homogeneously dispersed on the CNTs-NH3. However, NiB particles (13-23 nm)with amean size of 16 nm were scattered on the CNTs-HNO3.As a result, the activity and selectivity of NiB/CNTs-NH3 were higher than those of NiB/CNTs-HNO3 in the selective hydrogenation of acetylene.

scholarly journals ZnFe2O4-TiO2Nanoparticles within Mesoporous MCM-41

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Aidong Tang ◽  
Yuehua Deng ◽  
Jiao Jin ◽  
Huaming Yang
Keyword(s):  
Sol Gel ◽  
Rutile Phase ◽  
Band Gap Energy ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Agglomeration Of Nanoparticles ◽  
Adsorption Desorption ◽  
Mcm 41

A novel nanocomposite ZnFe2O4-TiO2/MCM-41 (ZTM) was synthesized by a sol-gel method and characterized through X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), N2adsorption-desorption, Raman spectroscopy, and ultraviolet visible (UV-vis) spectrophotometry. The results confirmed the incorporation of ZnFe2O4-TiO2nanoparticles inside the pores of the mesoporous MCM-41 host without destroying its integrity. ZnFe2O4nanoparticles can inhibit the transformation of anatase into rutile phase of TiO2. Incorporation of ZnFe2O4-TiO2within MCM-41 avoided the agglomeration of nanoparticles and reduced the band gap energy of TiO2to enhance its visible light photocatalytic activity. UV-vis absorption edges of ZTM nanocomposites redshifted with the increase of Zn/Ti molar ratio. The nanocomposite approach could be a potential choice for enhancing the photoactivity of TiO2, indicating an interesting application in the photodegradation and photoelectric fields.

Changing the morphology of one-dimensional titanate nanostructures affects its tissue distribution and toxicity

2020 ◽  
Vol 36 (4) ◽  
pp. 272-286
Author(s):  
Nahla Kamal ◽  
AH Zaki ◽  
Ahmed AG El-Shahawy ◽  
Ossama M Sayed ◽  
SI El-Dek
Keyword(s):  
Tissue Distribution ◽  
Surface Area ◽  
Inductively Coupled Plasma ◽  
Histopathological Analysis ◽  
X Ray Diffraction ◽  
One Dimensional ◽  
Inductively Coupled ◽  
Transmission Electron ◽  
Titanate Nanostructures ◽  
The Impact

The present research investigated the impact of the morphology change of titanate (TiO2) nanostructures on its tissue distribution and toxicity. The TiO2 nanotubes, rods, and ribbons were synthesized by the hydrothermal technique, and the morphology was adjusted by alteration of the hydrothermal duration time. The characterization techniques were X-ray diffraction, high-resolution transmission electron microscopy, dynamic light scattering, and the Brunauer–Emmett–Teller method for measuring the surface area. The intravenously administrated dose (5 mg/kg) was injected as a single dose for 1 day and consecutively for 42 days. The quantitative analysis of accumulated TiO2 nanostructures in the liver, spleen, and the heart was performed using an inductively coupled plasma emission spectrometer, and the organs’ toxicity was estimated by histopathological analysis. The prepared nanostructures exhibited differences in morphology, crystallinity, size distribution, surface area, zeta potential, and aspect ratio. The results revealed a tissue distribution difference between the liver, spleen, and heart of these nanostructures, the distribution order was the liver, spleen, and the heart for all TiO2 nanostructures. The toxicity was induced with different degrees. The nanotubes were the most harmful among the three formats. In summary, changes in the morphology of the TiO2 nanostructures change its distribution and toxicity.

scholarly journals Fabrication of the Hierarchical HZSM-5 Membrane with Tunable Mesoporosity for Catalytic Cracking of n-Dodecane

Catalysts ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 155 ◽  
Author(s):  
Zhenheng Diao ◽  
Lushi Cheng ◽  
Xu Hou ◽  
Di Rong ◽  
Yanli Lu ◽  
...  
Keyword(s):  
Catalytic Cracking ◽  
Inductively Coupled Plasma ◽  
Catalytic Performance ◽  
X Ray Diffraction ◽  
Inductively Coupled ◽  
Swelling Agent ◽  
Ft Ir ◽  
Temperature Programmed ◽  
Adsorption Desorption

Hierarchical HZSM-5 membranes were prepared on the inner wall of stainless steel tubes, using amphiphilic organosilane (TPOAC) and mesitylene (TMB) as a meso-porogen and a swelling agent, respectively. The mesoporosity of the HZSM-5 membranes were tailored via formulating the TPOAC/Tetraethylorthosilicate (TPOAC/TEOS) ratio and TMB/TPOAC ratio, in synthesis gel, and the prepared membranes were systematically characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), N2 adsorption–desorption, N2 permeation, inductively coupled plasma (ICP), in situ fourier transform infrared (FT-IR), ammonia temperature-programmed desorption (NH3-TPD), etc. It was found that the increase of the TPOAC/TEOS ratio promoted a specific surface area and diffusivity of the HZSM-5 membranes, as well as decreased acidity; the increase of the TMB/TPOAC ratios led to an enlargement of the mesopore size and diffusivity of the membranes, but with constant acid properties. The catalytic performance of the prepared HZSM-5 membranes was tested using the catalytic cracking of supercritical n-dodecane (500 °C, 4 MPa) as a model reaction. The hierarchical membrane with the TPOAC/TEOS ratio of 0.1 and TMB/TPOAC ratio of 2, exhibited superior catalytic performances with the highest activity of up to 13% improvement and the lowest deactivation rate (nearly a half), compared with the microporous HZSM-5 membrane, due to the benefits of suitable acidity, together with enhanced diffusivity of n-dodecane and cracking products.

scholarly journals Synthesis of Propylene Carbonate from Epoxide and CO2 Catalyzed by Carbon Nanotubes Supported Fe1.5PMo12O40

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Tahani Al-Garni ◽  
Nada Al-Jallal ◽  
Ahmed Aouissi
Keyword(s):  
Carbon Nanotubes ◽  
Propylene Carbonate ◽  
Inductively Coupled Plasma ◽  
Supported Catalyst ◽  
Catalyst Loading ◽  
X Ray Diffraction ◽  
Plasma Spectrometry ◽  
Inductively Coupled ◽  
Transmission Electron

Carbon nanotubes (CNTs) were functionalized and were then used as supports of Fe1.5PMo12O40 (FePMo) Keggin heteropolyanions catalysts. The characterization of the resulting catalysts was investigated by inductively coupled plasma spectrometry (ICP), Fourier transform infrared (FTIR) spectra, X-ray diffraction (XRD), ultraviolet-visible (UV-Vis) light spectroscopy, and transmission electron microscopy (TEM). FTIR and XRD results confirmed that FePMo was bounded on CNTs successfully and the Keggin structure was preserved. Characterization by TEM showed that solids with high FePMo content exhibited aggregation of FePMo in large particles. The as-prepared catalysts were tested in the synthesis of propylene carbonate (PC) from CO2 and propylene oxide (PO) in a solvent-free reaction and under mild conditions. Effects of various parameters, such as reaction temperature, reaction time, FePMo content on the support, and catalyst loading on the reaction, were investigated. It has been found that CNTs supported FePMo achieved 57.7% PO conversion and 99.0% PC selectivity, whereas unsupported FePMo led only to 8.5% conversion and 48.6% selectivity. The remarkable enhancement of the catalytic activity over the supported catalyst can be attributed mainly to the better dispersion and reactivity of the FePMo catalyst in the supported material.

Fabrication of hybrid composites based on biomineralization of phosphorylated poly(ethylene glycol) hydrogels

2009 ◽  
Vol 24 (1) ◽  
pp. 50-57 ◽  
Author(s):  
Chan Woo Kim ◽  
Sung Eun Kim ◽  
Yong Woo Kim ◽  
Hong Jae Lee ◽  
Hyung Woo Choi ◽  
...  
Keyword(s):  
Ethylene Glycol ◽  
Inductively Coupled Plasma ◽  
Hybrid Composites ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Poly Ethylene Glycol ◽  
3 Dimensional ◽  
Inductively Coupled ◽  
Poly Ethylene

A novel route to organic-inorganic composites was described based on biomineralization of poly(ethylene glycol) (PEG)-based hydrogels. The 3-dimensional hydrogels were synthesized by radical crosslinking polymerization of poly(ethylene glycol fumarate) (PEGF) in the presence of ethylene glycol methacrylate phosphate (EGMP) as an apatite-nuclating monomer, acrylamide (AAm) as a composition-modulating comonomer, and potassium persulfate (PPS) as a radical initiator. We used the urea-mediated solution precipitation technique for biomineralization of hydrogels. The apatite grown on the surface and interior of the hydrogel was similar to biological apatites in the composition and crystalline structure. Powder x-ray diffraction (XRD) showed that the calcium phosphate crystalline platelets on hydrogels are preferentially aligned along the crystallographic c-axis direction. Inductively-coupled plasma mass spectroscopy (ICP-MS) analysis showed that the Ca/P molar ratio of apatites grown on the hydrogel template was found to be 1.60, which is identical to that of natural bones. In vitro cell experiments showed that the cell adhesion/proliferation on the mineralized hydrogel was more pronounced than on the pure polymer hydrogel.

scholarly journals Hydrogenation of benzene and toluene over supported rhodium and rhodium-gold catalysts

2021 ◽  
Vol 340 ◽  
pp. 01026
Author(s):  
Sapar Konuspayev ◽  
Minavar Shaimardan ◽  
Nurlan Annas ◽  
T.S. Abildin ◽  
Y.Y. Suleimenov
Keyword(s):  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Gold Catalysts ◽  
Hydrogenation Reaction ◽  
Benzene Hydrogenation ◽  
X Ray Diffraction ◽  
Toluene Hydrogenation ◽  
Inductively Coupled ◽  
Transmission Electron ◽  
Colloidal Method

Rhodium and rhodium-gold catalysts supported on amorphous aluminosilicates (ASA), titanium dioxide (rutile, TiO2) was prepared in two different ways: absorption and colloidal method. The catalysts were characterized by an inductively coupled plasma optical emission spectrometer (ICP-OES), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The activity and selectivity of the prepared catalysts were tested by the hydrogenation of benzene and toluene. Hydrogenation was conducted at a pressure of 4 MPa and a temperature 80 °C. The bimetallic Rh-Au/ASA catalyst prepared by the absorption method showed higher activity and selectivity in benzene hydrogenation reaction, the same catalyst prepared by the colloidal method demonstrated lower selectivity.

scholarly journals Catalytic Properties of Alumina-Supported Ruthenium, Platinum, and Cobalt Nanoparticles towards the Oxidation of Cyclohexane to Cyclohexanol and Cyclohexanone

2018 ◽  
Vol 13 (1) ◽  
pp. 24
Author(s):  
Ilhem Rekkab-Hammoumraoui ◽  
Abderrahim Choukchou-Braham
Keyword(s):  
Inductively Coupled Plasma ◽  
Catalytic Properties ◽  
Optical Emission ◽  
Cobalt Nanoparticles ◽  
Impregnation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Inductively Coupled ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Transmission Electron

A series of metal-loaded (Ru, Pt, Co) alumina catalysts were evaluated for the catalytic oxidation of cyclohexane using tertbutylhydroperoxide (TBHP) as oxidant and acetonitrile or acetic acid as solvent. These materials were prepared by the impregnation method and then characterized by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), H2 chemisorption, Fourier Transformed Infrared Spectroscopy (FTIR), High-Resolution Transmission Electron Microscopy (HRTEM), and X-ray Diffraction (XRD). All the prepared materials acted as efficient catalysts. Among them, Ru/Al2O3 was found to have the best catalytic activity with enhanced cyclohexane conversion of 36 %, selectivity to cyclohexanol and cyclohexanone of 96 % (57.6 mmol), and cyclohexane turnover frequency (TOF) of 288 h-1. Copyright © 2018 BCREC Group. All rights reservedReceived: 26th May 2017; Revised: 17th July 2017; Accepted: 18th July 2017; Available online: 22nd January 2018; Published regularly: 2nd April 2018How to Cite: Rekkab-Hammoumraoui, I., Choukchou-Braham, A. (2018). Catalytic Properties of Alumina-Supported Ruthenium, Platinum, and Cobalt Nanoparticles towards the Oxidation of Cyclohexane to Cyclohexanol and Cyclohexanone. Bulletin of Chemical Reaction Engineering & Catalysis, 13(1): 24-36 (doi:10.9767/bcrec.13.1.1226.24-35) 

Preparation of Nanosized RuB with Lower Ru Content Supported on Al2O3 and its Catalytic Activity

2012 ◽  
Vol 557-559 ◽  
pp. 1467-1470
Author(s):  
Sheng Xian Xu ◽  
Feng Yi Li
Keyword(s):  
Catalytic Activity ◽  
Amorphous Alloy ◽  
Inductively Coupled Plasma ◽  
Chemical Reduction ◽  
Benzene Hydrogenation ◽  
Transmission Electron Micrograph ◽  
X Ray Diffraction ◽  
Inductively Coupled ◽  
Transmission Electron ◽  
Loading Amount

The nanosized RuB amorphous alloys with three different ruthenium contents supported on Al2O3 were prepared by means of impregnation, following the chemical reduction with KBH4 solution. The gas-phase benzene hydrogenation was used as a probe reaction to evaluate the catalytic activity of the prepared catalysts. The catalysts were characterized by BET, inductively coupled plasma (ICP), X-ray diffraction (XRD), and transmission electron micrograph (TEM). The experiment results show that the catalytic activity of the three amorphous alloy catalysts goes up first with the increasing of temperature and has a maximum at 443K; when the Ru loading amount is 0.24 %(wt.%) of the catalyst, which is very few, the conversion of benzene on RuB/Al2O3 amorphous alloy catalyst can reach to 99.50% at 443K.

scholarly journals Comparison of Two Novel Solution-Based Routes for the Synthesis of Equiaxed ZnO Nanoparticles

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
K. Elen ◽  
A. Kelchtermans ◽  
H. Van den Rul ◽  
R. Peeters ◽  
J. Mullens ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Inductively Coupled Plasma ◽  
Solvothermal Method ◽  
Atomic Emission ◽  
Correlation Spectroscopy ◽  
X Ray Diffraction ◽  
Inductively Coupled ◽  
Transmission Electron ◽  
Dimensional Growth ◽  
20 Nm

Due to a dominant one-dimensional growth rate, nanoparticles of zinc oxide often show a rodlike morphology. As a result, the synthesis of small spherical nanoparticles of undoped ZnO remains challenging. This paper presents two procedures that successfully produce a powder consisting of equiaxed zinc oxide nanoparticles: one using a polyethylene glycol- (PEG-) assisted solvothermal method and the other by calcination of zinc oxalate obtained from a microemulsion-mediated method. In the latter, zinc-substituted aerosol OT (AOT) is used as a surfactant. The samples are characterized by inductively coupled plasma-atomic emission spectroscopy (ICP-AES), thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), photon correlation spectroscopy (PCS), and photoluminescence (PL) spectroscopy. Both synthesis techniques produce nanoparticles with similar sizes in the range of 10 to 20 nm. Dense aggregates observed in the calcined powder are infrequent in the case of the solvothermal method.

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