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1.
J Nanosci Nanotechnol ; 21(7): 4085-4088, 2021 07 01.
Article in English | MEDLINE | ID: mdl-33715750

ABSTRACT

(PPh3)Mo(CO)5 and (PPh3)2Mo(CO)4 were synthesized by the reaction of molybdenum hexacar-bonyl with triphenylphosphine and applied as precursors to hydrocracking of vacuum residue under high-pressure and high-temperature conditions. (PPh3)2Mo(CO)4 could also be synthesized by the reaction of (PPh3)Mo(CO)5 with triphenyl phosphine. A commercial precursor (Mo-octoate) for hydrocracking of vacuum residue was used for comparison. The thermal decomposition behavior of (PPh3)Mo(CO)5, (PPh3)2Mo(CO)4, and Mo-octoate was also examined by the thermogravimetric analysis. The TGA curve of (PPh3)Mo(CO)5 and (PPh3)2Mo(CO)4 showed a similar weight-loss pattern. (PPh3)Mo(CO)5 and (PPh3)2Mo(CO)4 were decomposed into Mo metal and ligands rapidly in the range of 140 °C~270 °C. There were no ligands bound to a metal center of (PPh3)Mo(CO)5 and (PPh3)2Mo(CO)4 at the reaction temperature (430 °C) of hydrocracking. The amount of coke formed after hydrocracking over (PPh3)Mo(CO)5 and (PPh3)2Mo(CO)4 was 2.3% and 0.5%, respectively. Upgrading the qualities of heavy oils is an important issue in the energy industry. It is not easy to achieve the complete conversion of vacuum residue due to coke forming during hydrocracking of vacuum residue. This study showed that (PPh3)2Mo(CO)4 was considerably effective in reducing coke formation.


Subject(s)
Molybdenum , Organophosphorus Compounds , Ligands , Vacuum
2.
J Nanosci Nanotechnol ; 20(9): 5787-5790, 2020 09 01.
Article in English | MEDLINE | ID: mdl-32331181

ABSTRACT

In this study, Molybdenum precursors were synthesized with Triphenylphosphine, 1,2-Bis(diphenylphosphino)ethane, Pyridine, 2,2-Bipyridine as a ligands. The molybdenum precursors was used for Hydrocraking reaction of Vacuum Residue (VR). Hydrocracking reactions were carried out under the 430 °C and H2 pressure of 80 bar in an 100 ml high pressure reactor. New Molybdenum precursors were tested and their activities were compared with Mo-octoate. The Molybdeum-Phosphine precursor showed the best performances, high yield and low coke contents (below 0,5 wt%), in of hydrocracking for VR. To characterize the physicochemical properties of Moprecursor catalyst, various characterization techniques (NMR, XPS) were carried out. We confirmed that cokes in the reactor were contained the P atoms derived from ligand of Mo-precursor after hydrocracking of VR.

3.
J Nanosci Nanotechnol ; 19(2): 1196-1199, 2019 02 01.
Article in English | MEDLINE | ID: mdl-30360233

ABSTRACT

Styrenated phenols (SPs) are usually synthesized by the reaction of styrene and phenol under acid catalysts. SPs with a high content of di-styrenated phenol (DSP) can be used to prepare styrenated phenol alkoxylate (SP-A). Therefore, in this study, a scale-up process for synthesizing SPs with high DSP content which can be used for synthesis of SP-A was studied. The solid catalyst used in this study was prepared by impregnation method. SO2-4 was impregnated on a SO2-4/ZrO2 catalyst in an aqueous 1 M H2SO4 solution. The prepared catalysts were characterized by NH3-TPD. Catalytic activity was examined by measuring the conversion of phenol and styrene in a liquid-phase batch reactor. Almost 100% conversion of both phenol and styrene over 5-SO2-4/ZrO2 catalyst was obtained at a reaction temperature of 80 °C and a reaction time of 6 h. The amount of catalyst to the reactants was 2 wt%. Under the same reaction conditions, the selectivity of MSP, DSP, and TSP was 12.4%, 64.5%, and 23.1% respectively.

4.
J Nanosci Nanotechnol ; 19(2): 1200-1203, 2019 02 01.
Article in English | MEDLINE | ID: mdl-30360234

ABSTRACT

Styrenated phenol alkoxylates (SP-A) are prepared from styrenated phenols (SP) and ethylene oxide (EO) under a homogeneous base catalyst. However, to use EO that is difficult to handle, a high-pressure reaction device capable of reaction process control should be used. Additionally, the homogeneous base catalyst requires a neutralization process to remove the remaining catalyst after the reaction, and it is difficult to separate the catalysts and the product. Therefore, in this study, the separation of product and catalyst by using KOH/La2O3 catalyst was facilitated in the production of SP-A. Also, it was possible to produce SP-A under atmospheric pressure reaction conditions using EC. The mean molecular weight of SP-A varied depending on the reaction conditions, and the size of the mean molecular weight could be arbitrarily controlled by changing the reaction conditions.

5.
J Nanosci Nanotechnol ; 18(2): 1457-1460, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-29448613

ABSTRACT

Styrenated phenols (SPs) involving very small amount of unreacted phenol and high content of di-SP (DSP) were synthesized, which can be used to prepare SP alkoxylate. The solid catalyst was prepared by impregnation method. SO2-4 on SO2-4/MxOy catalyst was introduced from an aqueous 1M-H2SO4 solution. The catalysts were characterized by XRD patterns, and FT-IR spectra. The catalytic activity was examined by measuring conversion of phenol and styrene in a batch liquid-phase reactor. The concentration of phenol, styrene, and SPs were measured by GC with capillary column. The optimum synthesis conditions for concentration of sulfuric acid solution, catalyst amount of reactants, reaction temperature, and reaction time over SO2-4/ZrO2 catalyst were 15 wt%, 15 wt%, 100 °C, and 6 hr, respectively. At these conditions, conversion of both phenol and styrene were almost 100%, and the selectivity of DSP was 52.1%. On the other hand, the optimum synthesis conditions over SO2-4/TiO2 catalyst were 10 wt%, 5 wt%, 100 °C, and 1 hr, respectively, and conversion of both phenol and styrene were almost 100%, and the selectivity of DSP was 66.1%.

6.
J Nanosci Nanotechnol ; 18(2): 1461-1464, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-29448614

ABSTRACT

Styrenated phenol was prepared by an alkylation of phenol using NiCl2 and AlCl3 supported on silica gel. The conversion of phenol and styrene of alkylation reaction, and the selectivity of styrenated phenol were investigated. The Al · Ni/SiO2 Supported catalyst was used, the conversion of phenol was almost 100%. The product was in the form of a mixture of mono-styrenated phenol, di-styrenated phenol and tri-styrenated phenol. The styrenated phenol were selectivity of the varies depending on the reaction conditions.

7.
J Nanosci Nanotechnol ; 18(2): 1465-1467, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-29448615

ABSTRACT

In this study, Molybdenum precursors were synthesized with butanoic acid, hexanoic acid, nonanoic acid, decanoic acid, and undecanoic acid. In order to determine chemical structure of Synthesized molybdenum precursors, 1H(13C)-NMR, EA and ICP were used pyrolysis properties were measured TGA. The molybdenum precursors was used for Hydrocracking of Vacuum R1esidue (VR). It was shown that molybdenum nonanoate(3) was shown the lowerst Toluene Insoluble and Gas Product about 2.1 and 5.0 percent.

8.
J Nanosci Nanotechnol ; 17(4): 2776-779, 2017 Apr.
Article in English | MEDLINE | ID: mdl-29667804

ABSTRACT

Styrenated phenols are usually synthesized by the reaction of styrene and phenol under acid catalysts. Styrenated phenol involving high content of di-styrenated phenol (DSP) was synthesized, which can be used to prepare styrenated phenol alkoxylate. The solid catalyst used in this study was prepared by impregnation method. SO4 2- on SO4 2-/ZrO2 catalyst was introduced from an aqueous 1M-H2SO4 solution. The catalysts were characterized by SEM images, XRD patterns, and FT-IR spectra. The catalytic activity was examined by measuring the conversion of phenol and styrene in a liquid-phase batch reactor. Almost 100% conversion of both phenol and styrene over 15-SO4 2-/ZrO2 catalyst were obtained at reaction temperature of 100 °C and reaction time of 6 hr. Amount of catalyst to the reactants was 15 wt%. At same reaction conditions, selectivity of MSP, DSP, and TSP were 23.6%, 52.1%, and 5.4%, respectively. It was known that the selectivity to DSP was increased as IR absorption peak of 1236 cm-1 corresponding to O­S­O bonds was increased.

9.
J Nanosci Nanotechnol ; 16(5): 4643-6, 2016 May.
Article in English | MEDLINE | ID: mdl-27483804

ABSTRACT

The TiO2 powder was prepared from the spent titanium chips by applying the sol-gel method. The spent titanium chip was dissolved in HCl solution, and then NH4OH solution was added. The molar concentration of NH4OH solution was 2 M, 4 M, 8 M, and 10 M. Obtained TiO2 powders were calcined at 200 degrees C, 400 degrees C, and 600 degrees C. The prepared TiO2 powder was characterized using a particle size analysis, BET surface area, and XRD analysis. The crystal structure of the TiO2 powder was rutile type and anatase. The highest BET surface area of TiO2 powder was 432.8 m2/g. The photocatalytic property of the TiO2 powder was evaluated as decomposition rate of methylene blue(MB) by using a liquid phase stirred reactor. UV source was a UV-A, and concentration of MB in most experiments was 8 ppm. The concentration of MB was measured by absorbance at 664 nm using UV spectroscopy. Photocatalytic efficiency of prepared TiO2 powder depended highly on concentration of NH4OH solution. The TiO2 powder prepared with 8 M-NH4OH solution showed the highest efficiency, the decomposition efficiency at decomposition time of 2 hr and MB concentration of pH 8 was 98%.

10.
J Nanosci Nanotechnol ; 16(2): 2024-7, 2016 Feb.
Article in English | MEDLINE | ID: mdl-27433722

ABSTRACT

In this study, titanium chips (TC) generated from industrial facilities was utilized as TiO2 support for hydrogenation of carbon dioxide (CO2) to methyl alcohol (CH3OH) over Cu-based catalysts. Nano-sized CuO and ZnO catalysts were deposited on TiO2 support using a co-precipitation (CP) method (CuO-ZnO/TiO2), where the thermal treatment of TC and the particle size of TiC2 are optimized on CO2 conversion under different reaction temperature and contact time. Direct hydrogenation of CO2 to CH3OH over CuO-ZnO/TiO2 catalysts was achieved and the maximum selectivity (22%) and yield (18.2%) of CH3OH were obtained in the range of reaction temperature 210-240 degrees C under the 30 bar. The selectivity was readily increased by increasing the flow rate, which does not affect much to the CO2 conversion and CH3OH yield.

11.
J Nanosci Nanotechnol ; 16(2): 2080-3, 2016 Feb.
Article in English | MEDLINE | ID: mdl-27433733

ABSTRACT

Liquid phase plasma (LPP) process was applied to the impregnation of copper nanoparticles onto graphene sheet. Approximately 30-50 nm sized tetragonal nanoparticles were dispersed uniformly on the surface of the two-dimensional graphene sheet. The amount of copper nanoparticles precipitated increased with increasing LPP process time. When combined with a subsequent process, the synthesized copper/graphene nanocomposites will be able to high-performance Li-ion batteries effectively.

12.
J Nanosci Nanotechnol ; 15(7): 5338-41, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26373137

ABSTRACT

The reaction of platinum [Pt(4-(N,N-bis(piridyl)amino)stilbene)]Cl2 with 5,5"-(9,9-dioctyl-9H-fluorene- 2,7-diyl)di-2,2'-bipyridine, 2,2'-bipyridine, and 1,10-phenathroline affords the following complexes: [(4-(N,N-bis(piridyl)amino)stilbene)Pt(5,5"-(9,9-dioctyl-9H-fluorene-2,7-diyl)di-2,2'-bipyridine)] (1), [(4-(N,N-bis(piridyl)amino)stilbene)Pt(2,2'-bipyridine)] (2), and [(4-(N,N-bis(piridyl)amino)stilbene) Pt(1,10-phenathroline)] (3). In this study, new platinum complex compounds were synthesized utilizing the ligand of a 4-(N,N-bis(piridyl)amino)stilbene system. These complexes were analyzed using a 1H(13C)-NMR, UV-vis and PL spectrophotometer. The maximum wavelengths of complexes 1, 2, and 3 appear at 409 nm, 410 nm, and 503 nm, respectively. The quantum yields of these complexes are 0.32-0.92.

13.
J Nanosci Nanotechnol ; 15(7): 5350-3, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26373140

ABSTRACT

Al nanoparticles were synthesized in liquid phase plasma using Al chloride as the precursor. CTAB was used as the surfactant to obtain well dispersed particles. When the surfactant was not added, large aggregated particles were generated. With increasing CTAB dosage, the size of the Al particles decreased and the degree of dispersion of the particles increased. At the initial stage of plasma discharge, dendrite shaped particles were produced. As discharge time evolved, however, particle size decreased and the particle morphology also changed into spherical shape. The solution pH decreased with increasing plasma discharge time.

14.
J Nanosci Nanotechnol ; 15(7): 5466-70, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26373161

ABSTRACT

The TiO2 powder was prepared from the spent titanium chips by applying the sol-gel method with neutralization by NaOH solution. The prepared TiO2 powder was characterized using a particle size analysis, BET surface area, and XRD analysis. The crystal structure of the TiO2 powder was rutile type, and the powder was obtained to be nanosized. BET surface area of TiO2 powder was 118 m2/g, average particle size was 266.5 nm. The photocatalytic property of the TiO2 powder was evaluated as decomposition rate of methylene blue (MB) by using a liquid phase stirred reactor. Decomposition rate on TiO2 powder (P-25) was 1.5 times higher than that of the prepared TiO2 powder. Decomposition rate on the prepared TiO2 powder was linearly increased with increasing the amount of TiO2 powder, and approached to a specific value. MB concentration and decomposition rate was not correlated within the experimental range. The maximum value of decomposition rate at about pH 8 was 62%.

15.
J Nanosci Nanotechnol ; 15(1): 518-21, 2015 Jan.
Article in English | MEDLINE | ID: mdl-26328393

ABSTRACT

The liquid-phase plasma reduction method has been applied to prepare iron nanoparticles from iron chloride solution using a bipolar pulsed electrical discharge system. The excited states of atomic iron, hydrogen, and oxygen as well as the molecular bands of hydroxyl radicals were detected in the emission spectra. The iron nanoclusters formed at the initial stage convert to dispersion of small iron nanoparticles, which then grows slowly to form anisotropic, tetragonal shape. The cationic surfactant of CTAB was shown to exhibit a large influence on the particle generation procedure.


Subject(s)
Cetrimonium Compounds/chemistry , Magnetite Nanoparticles/chemistry , Plasma Gases/chemistry , Surface-Active Agents/chemistry , Cetrimonium , Hydrogen-Ion Concentration , Microscopy, Electron, Transmission , Particle Size
16.
J Nanosci Nanotechnol ; 15(1): 570-4, 2015 Jan.
Article in English | MEDLINE | ID: mdl-26328404

ABSTRACT

The greenhouse effect of carbon dioxide (CO2) has been recognized as one of the most serious problems in the world. Conversion of CO2 to methyl alcohol (CH3OH) was studied using catalytic chemical methods. Honeycomb-typed monolith used as catalyst support was 400 cell/inch2. Pretreatment of the monolith surface was carried out by thermal treatment and acid treatment. Monolith-supported nanosized CuO-ZnO catalysts were prepared by wash-coat method. The prepared catalysts were characterized by using SEM, TEM, and XRD. The catalytic activity for CO2 hydrogenation to CH3OH was investigated using a flow-type reactor with varying reaction temperature, reaction pressure and contact time. Conversion of CO2 was increased with increasing reaction temperature, but selectivity to CH3OH was decreased. Optimum reaction temperature was about 250 degrees C under 20 atm. Because of the reverse water gas shift reaction.


Subject(s)
Carbon Dioxide/chemistry , Chemistry Techniques, Synthetic/instrumentation , Chemistry Techniques, Synthetic/methods , Copper/chemistry , Methanol/chemistry , Zinc Oxide/chemistry , Equipment Design , Hydrogenation
17.
J Nanosci Nanotechnol ; 15(2): 1389-95, 2015 Feb.
Article in English | MEDLINE | ID: mdl-26353661

ABSTRACT

Complexes 1 and 2 were obtained by the reaction of [Cu(L1)](ClO4)2 (1) or [Cu(L2)](ClO4)2 (2) (L1 = 8-acetyl-1,3,6,8,10,13,15-heptaazatricyclo[13.1.1.113,15]octadecane, L2 = 3,7-bis(2-aminoethyl)- 1,3,5,7-tetraazabicyclo[3.3.l]decane) with K2[Pt(CN)4] in water. The X-ray crystal structures show that the geometry around Cu(II) ions of 1 and 2 adopts a square-pyramid. Their one-dimensional and two-dimensional structures are constructed by the intermolecular hydrogen bonding between the macrocyclic ligand and anionic complex ions or water molecules and Pt-Pt interaction. They show luminescent property and luminescence quantum yields are 0.341 and 0.187 for 1 and 2 in solid, respectively.

18.
J Nanosci Nanotechnol ; 14(8): 6213-6, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25936089

ABSTRACT

The reaction of platinum [Pt(5,5-dmbpy)]Cl2 (5,5-dmbpy = 5,5'-dimethyl-2,2'-bipyridine) with 4,4'-dimethyl-2,2'-bipyridine (4,4-dmbpy), [Pt(dbbpy)]Cl2 (dbbpy = 4,4'-dibutyl-2,2'-bipyridine), [Pt(dpbpy)]Cl2 (dpbpy = 4,4'-dipentyl-2,2'-bipyridine) with 5,5'-dimethyl-2,2'-bipyridine (5,5-dmbpy) affords the following complexes: [(4,4-dmbpy)Pt(5,5-dmbpy)][PF6]2 (1) and [(dbbpy)Pt(5,5-dmbpy)][PF6]2 (2), [(dpbpy)Pt(5,5-dmbpy)][PF6]2 (3), [(5,5-dmbpy)Pt(5,5-dmbpy)][PF6]2 (4). This study was synthesized new platinum complex compounds utilizing ligand of 5,5'-Dimethyl-2,2'-dipyridyl System. To study the chemical composition was used 1H(13C)-NMR, UV-vis, Spectro photometer and Measurements about optical physics and chemical properties were measured to use spectrofluorometer. UV-vis absorption area was measured 310 nm to 383 nm and luminous wavelength was measured 390 nm to 419 nm.


Subject(s)
Platinum/chemistry , Pyridines/chemistry , Luminescence , Magnetic Resonance Spectroscopy
19.
J Nanosci Nanotechnol ; 13(8): 5823-6, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23882842

ABSTRACT

In order to reutilize spent metallic titanium chips (TC) as catalyst support or photocatalytic materials, the surface of the TC was modified by thermal treatment under air atmosphere. TC-supported nanosized CuO and ZnO catalysts were prepared by impregnation (IMP) and co-precipitation (CP) method, respectively. The catalytic activity for CO2 hydrogenation to CH3OH was investigated using a flow-typed reactor under various reaction pressures. The crystals of CuO and ZnO was well formed on TC. CO2 conversion, CH3OH selectivity, and CH3OH yield were obtained as a function of time on stream over CuO-ZnO/TC catalysts. Conversion of CO2 to CH3OH over CuO-ZnO/TC catalyst by CP method and CuO/ZnO/TC catalyst by IMP method were ca. 16% and ca. 12%, respectively. Conversion of CO2 over CuO-ZnO/TC catalyst by CP method was increased with increasing reaction temperature in the range of 15-30 atm. Maximum selectivity and yield to CH3OH over CuO-ZnO/TC at 250 degrees C were ca. 90% at 20 atm and ca. 18.2% at 30 atm, respectively.

20.
J Nanosci Nanotechnol ; 13(8): 5879-82, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23882853

ABSTRACT

In order to reutilize the spent metallic titanium chips, TiO2 photocatalysts were prepared using the self-propagating high-temperature synthesis (SHS) method, and were characterized by N2 gas adsorption, X-ray diffraction, and scanning electron microscope, particle size distribution. Also, their photocatalytic activities were evaluated using methylene blue as a model organic compound. It was confirmed that the crystal structure of TiO2 prepared by SHS method was relatively homogeneous powder of rutile type. Optimum conditions for photocatalytic degradation of methylene blue under UV-C irradiation were methylene blue 9.5 ppm in solution and at amount of TiO2 added of 0.02 g/L. In addition, it was found that the photocatalytic activity for methylene blue degradation over the prepared TiO2 particles was positively related with BET specific surface area.

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