Pt-Promoted Tungsten Carbide Nanostructures on Mesoporous Pinewood-Derived Activated Carbon for Catalytic Oxidation of Formaldehyde at Low Temperatures

Tungsten carbide (WC) nanostructures were prepared by carbothermal reduction (CR) of tungsten-impregnated pinewood-derived activated carbon (AC) at 1000 °C under an inert atmosphere. Brunauer-Emmet-Teller (BET) surface area, pore structures of the AC, and catalyst samples were evaluated by N2 adsorption-desorption experiments. The structures of the catalysts were characterized using X-ray powder diffraction (XRD). The morphologies and particle structures of the synthesized WC nanoparticles were investigated by field emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM). The WC/AC material was used as support of the platinum catalysts for catalytic oxidation of formaldehyde (HCHO) from interior sources. Pt-WC/AC catalysts with different platinum loadings were assessed for the catalytic oxidation of HCHO at low temperature. The catalytic performance was found to be significantly influenced by reaction temperature, initial formaldehyde concentration, relative humidity, and space velocity. The testing results demonstrated that HCHO can be totally oxidized by the 1 wt% Pt-WC/AC catalyst in the gas hourly space velocity (GHSV) = 50,000 h−1 at 30 °C with a relative humidity (RH) of 40%.

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Interconnected Micro, Meso, and Macro Porous Activated Carbon from Bacterial Nanocellulose for Superior Adsorption Properties and Effective Catalytic Performance

Molecules ◽

10.3390/molecules25184063 ◽

2020 ◽

Vol 25 (18) ◽

pp. 4063

Author(s):

Arnon Khamkeaw ◽

Tatdanai Asavamongkolkul ◽

Tianpichet Perngyai ◽

Bunjerd Jongsomjit ◽

Muenduen Phisalaphong

Keyword(s):

Activated Carbon ◽

Reaction Temperature ◽

Mass Transfer Rate ◽

Catalyst Support ◽

Catalytic Performance ◽

Adsorption Properties ◽

Bet Surface Area ◽

Ethanol Conversion ◽

Bacterial Nanocellulose ◽

Effective Performance

The porous carbon (bacterial cellulose (BC)-activated carbon (AC)(BA)) prepared via two-step activation of bacterial nanocellulose by treatments with potassium hydroxide (KOH) and then phosphoric acid (H3PO4) solutions showed superior adsorption properties and effective performance as catalyst support. BC-AC(BA) had an open and interconnected multi-porous structure, consisting of micropores (0.23 cm3/g), mesopores (0.26 cm3/g), and macropores (4.40 cm3/g). The BET surface area and porosity were 833 m2/g and 91.2%, respectively. The methylene blue adsorption test demonstrated that BC-AC(BA) was superior in its mass transfer rate and adsorption capacities. Moreover, BC-AC(BA) modified by H3PO4 treatment showed a significant enhancement of catalytic performance for dehydration of ethanol. At the reaction temperature of 250–400 °C, 30P/BC-AC(BA) gave ethanol conversion at 88.4–100%, with ethylene selectivity of 82.6–100%, whereas, high selectivity for diethyl ether (DEE) at 75.2%, at ethanol conversion of 60.1%, was obtained at the reaction temperature of 200 °C.

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Catalytic Soot Oxidation Activity of NiO–CeO2 Catalysts Prepared by a Coprecipitation Method: Influence of the Preparation pH on the Catalytic Performance

Materials ◽

10.3390/ma12203436 ◽

2019 ◽

Vol 12 (20) ◽

pp. 3436 ◽

Cited By ~ 1

Author(s):

Amar Bendieb Aberkane ◽

María Pilar Yeste ◽

Djazi Fayçal ◽

Daniel Goma ◽

Miguel Ángel Cauqui

Keyword(s):

Electron Microscopy ◽

Surface Area ◽

Mixed Oxide ◽

Soot Oxidation ◽

Catalytic Performance ◽

Coprecipitation Method ◽

Bet Surface Area ◽

Mixed Oxide Catalysts ◽

Ph Values ◽

Tight Contact

A series of NiO–CeO2 mixed oxide catalysts have been synthesized by a modified coprecipitation method at three different pH values (pH = 8, 9, and 10). The NiO–CeO2 mixed oxide samples were characterized by TGA, XRD, inductively coupled plasma atomic emission spectroscopy (ICP-AES), FTIR, Brunauer–Emmett–Teller (BET) surface area, H2 temperature-programmed reduction (H2-TPR), and electron microscopy (high-angle annular dark-field transmission electron microscopy/energy-dispersive X-ray spectroscopy (HAADF-TEM/EDS)). The catalytic activities of the samples for soot oxidation were investigated under loose and tight contact conditions. The catalysts exhibited a high BET surface area with average crystal sizes that varied with the pH values. Electron microscopy results showed the formation of small crystallites (~5 nm) of CeO2 supported on large plate-shaped particles of NiO (~20 nm thick). XRD showed that a proportion of the Ni2+ was incorporated into the ceria network, and it appeared that the amount on Ni2+ that replaced Ce4+ was higher when the synthesis of the mixed oxides was carried out at a lower pH. Among the synthesized catalysts, Ni-Ce-8 (pH = 8) exhibited the best catalytic performance.

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SURFACE PROPERTIES AND CATALYTIC PERFORMANCE OF ACTIVATED CARBON FIBERS SUPPORTED TiO2 PHOTOCATALYST

Surface Review and Letters ◽

10.1142/s0218625x08011469 ◽

2008 ◽

Vol 15 (04) ◽

pp. 337-344 ◽

Cited By ~ 5

Author(s):

HUIFEN YANG ◽

PINGFENG FU

Keyword(s):

Activated Carbon ◽

Carbon Fibers ◽

Uv Light ◽

Three Dimensional ◽

Catalytic Performance ◽

Dip Coating ◽

Bet Surface Area ◽

Activated Carbon Fibers ◽

Organic Silicon ◽

Acrylate Copolymer

Activated carbon fibers supported TiO 2 photocatalyst ( TiO 2/ACF) in felt-form was successfully prepared with a dip-coating process using organic silicon modified acrylate copolymer as a binder followed by calcination at 500°C in a stream of Ar gas. The photocatalyst was characterized by SEM, XRD, XPS, FTIR, and BET surface area. Most of carbon fibers were coated with uniformly distributed TiO 2 clusters of nearly 100 nm. The loaded TiO 2 layer was particulate for the organic binder in the compact film was carbonized. According to XPS and FTIR analysis, amorphous silica in carbon grains was synthesized after carbonizing organic silicon groups, and the Ti – O – Si bond was formed between the interface of loaded TiO 2 and silica. Additionally, the space between adjacent carbon fibers still remained unfilled after TiO 2 coating, into which both UV light and polluted solutions could penetrate to form a three-dimensional environment for photocatalytic reactions. While loaded TiO 2 amount increased to 456 mg TiO 2/1 g ACF, the TiO 2/ACF catalyst showed its highest photocatalytic activity, and this activity only dropped about 10% after 12 successive runs, exhibiting its high fixing stability of coated TiO 2.

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Adsorption of Heavy Metal on Active Carbon Derived from Coconut Leaves Agro-Waste

Chemistry & Chemical Technology ◽

10.23939/chcht14.04.553 ◽

2020 ◽

Vol 14 (4) ◽

pp. 553-562

Author(s):

Abhijit Jadhav ◽

◽

Govindaraj Mohanraj ◽

Suseeladevi Mayadevi ◽

Ashok Gokarn ◽

...

Keyword(s):

Activated Carbon ◽

Chemical Activation ◽

Solute Concentration ◽

Inert Atmosphere ◽

Bet Surface Area ◽

Solution Temperature ◽

First Order ◽

Pseudo Second Order ◽

Pseudo First Order ◽

Sorption Study

In this paper activated carbon is prepared from coconut leaves by chemical activation during slow pyrolysis at 673 K in an inert atmosphere. Activated carbon is prepared in the stiochiometric ratio of 1:1 (CL1), 2:1 (CL2) and 3:1 (CL3). Optimized 3:1 ratio is preferable for further study. BET surface area of CL3 activated carbon was found 1060.57 m2/g. It is greater than those of CL1 and CL2. The batch sorption study experiments were conducted with respect to solute concentration of 2.5–122.8 mg/l and solution temperature of 313–343 K. The Langmuir, Freundlich and Temkin isotherm studies were conducted. The experimental data fitted very well for the pseudo-first order and pseudo-second-order. The results have established good potentiality for the CL3 activated carbon to be used as a sorbent for the removal of lead from wastewater.

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The Impact of Ce-Zr Addition on Nickel Dispersion and Catalytic Behavior for CO2 Methanation of Ni/AC Catalyst at Low Temperature

Journal of Chemistry ◽

10.1155/2017/4361056 ◽

2017 ◽

Vol 2017 ◽

pp. 1-11 ◽

Cited By ~ 13

Author(s):

Minh Cam Le ◽

Khu Le Van ◽

Thu Ha T. Nguyen ◽

Ngoc Ha Nguyen

Keyword(s):

Electron Microscopy ◽

Activated Carbon ◽

Catalytic Performance ◽

Solid Solution Phase ◽

Carbon Phase ◽

Co2 Methanation ◽

Transmission Electron ◽

Nickel Species ◽

Nickel Dispersion ◽

The Impact

The CO2 methanation was studied over 7 wt.% nickel supported on Ce0.2Zr0.8O2/AC to evaluate the correlation of the structural properties with catalytic performance. The catalysts were investigated in more detail by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). A sample of 7 wt.% nickel loading supported on activated carbon (AC) was also prepared for comparison. The results demonstrated that the ceria-zirconia solid solution phase could disperse and stabilize the nickel species more effectively and resulted in stronger interaction with nickel than the parent activated carbon phase. Therefore, 7% Ni/Ce0.2Zr0.8O2/AC catalyst exhibited higher activity for CO2 reduction than 7% Ni//AC. It can attain 85% CO2 conversion at 350°C and have a CH4 selectivity of 100% at a pressure as low as 1 atm. The high activity of prepared catalysts is attributed to the good interaction between Ni and Ce0.2Zr0.8O2 and the high CO2 adsorption capacity of the activated carbon as well.

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Catalytic Performance of Activated Carbon Supported Tungsten Carbide for Hydrazine Decomposition

Catalysis Letters ◽

10.1007/s10562-008-9409-5 ◽

2008 ◽

Vol 123 (1-2) ◽

pp. 150-155 ◽

Cited By ~ 34

Author(s):

Jun Sun ◽

Mingyuan Zheng ◽

Xiaodong Wang ◽

Aiqin Wang ◽

Ruihua Cheng ◽

...

Keyword(s):

Activated Carbon ◽

Tungsten Carbide ◽

Catalytic Performance ◽

Hydrazine Decomposition

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Identification of Active Phase for Selective Oxidation of Benzyl Alcohol with Molecular Oxygen Catalyzed by Copper-Manganese Oxide Nanoparticles

Journal of Chemistry ◽

10.1155/2013/367261 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Roushown Ali ◽

S. F. Adil ◽

Abdulrahman Al-warthan ◽

M. Rafiq H. Siddiqui

Keyword(s):

Electron Microscopy ◽

Benzyl Alcohol ◽

Molecular Oxygen ◽

Selective Oxidation ◽

Catalytic Performance ◽

Area Measurement ◽

Bet Surface Area ◽

Oxide Nanoparticles ◽

Oxidation Of Benzyl Alcohol ◽

Copper Manganese

Catalytic activity of copper-manganese mixed oxide nanoparticles (Cu/Mn = 1 : 2) prepared by coprecipitation method has been studied for selective oxidation of benzyl alcohol using molecular oxygen as an oxidizing agent. The copper-manganese (CuMn2) oxide catalyst exhibited high specific activity of 15.04 mmolg−1 h−1in oxidation of benzyl alcohol in toluene as solvent. A 100% conversion of the benzyl alcohol was achieved with >99% selectivity to benzaldehyde within a short reaction period at 102°C. It was found that the catalytic performance is dependent on calcination temperature, and best activity was obtained for the catalyst calcined at 300°C. The high catalytic performance of the catalyst can be attributed to the formation of active MnO2phase or absence of less active Mn2O3phase in the mixed CuMn2oxide. The catalyst has been characterized by powder X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer Emmett-Teller (BET) surface area measurement, and Fourier transform infrared (FT-IR) spectroscopies.

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Synthesis and Characterization of Rh/B–TNTs as a Recyclable Catalyst for Hydroformylation of Olefin Containing –CN Functional Group

Nanomaterials ◽

10.3390/nano8100755 ◽

2018 ◽

Vol 8 (10) ◽

pp. 755 ◽

Cited By ~ 4

Author(s):

Penghe Su ◽

Xiaotong Liu ◽

Ya Chen ◽

Hongchi Liu ◽

Baolin Zhu ◽

...

Keyword(s):

Electron Microscopy ◽

Great Influence ◽

Average Diameter ◽

Atomic Emission ◽

Catalytic Performance ◽

Bet Surface Area ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Inner Diameter

The TiO2-based nanotubes (TNTs, B–TNTs) of different surface acidities and their supported Rh catalysts were designed and synthesized. The catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectrometer (XPS), tempera–ture–programmed desorption of ammonia (NH3–TPD), atomic emission spectrometer (ICP), and Brunauer–Emmett–Tellerv (BET) surface-area analyzers. Images of SEM and TEM showed that the boron-decorated TiO2 nanotubes (B–TNTs) had a perfect multiwalled tubular structure; their length was up to hundreds of nanometers and inner diameter was about 7 nm. The results of NH3-TPD analyses showed that B–TNTs had a stronger acid site compared with TNTs. For Rh/TNTs and Rh/B–TNTs, Rh nanoparticles highly dispersed on B–TNTs were about 2.79 nm in average diameter and much smaller than those on TNTs, which were about 4.94 nm. The catalytic performances of catalysts for the hydroformylation of 2-methyl-3-butennitrile (2M3BN) were also evaluated, and results showed that the existence of B in Rh/B–TNTs had a great influence on the catalytic performance of the catalysts. The Rh/B–TNTs displayed higher catalytic activity, selectivity for aldehydes, and stability than the Rh/TNTs.

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Zinc Oxide Nanoparticles from Waste Zn-C Battery via Thermal Route: Characterization and Properties

Nanomaterials ◽

10.3390/nano8090717 ◽

2018 ◽

Vol 8 (9) ◽

pp. 717 ◽

Cited By ~ 9

Author(s):

Rifat Farzana ◽

Ravindra Rajarao ◽

Pravas Behera ◽

Kamrul Hassan ◽

Veena Sahajwalla

Keyword(s):

Electron Microscopy ◽

Zno Nanoparticles ◽

Photoelectron Spectroscopy ◽

Uv Light ◽

Inert Atmosphere ◽

Bet Surface Area ◽

Visible Range ◽

Tem Analysis ◽

Thermal Synthesis ◽

X Ray

Disposable batteries are becoming the primary sources of powering day-to-day gadgets and consequently contributing to e-waste generation. The emerging e-waste worldwide is creating concern regarding environmental and health issues. Therefore, a sustainable recycling approach of spent batteries has become a critical focus. This study reports the detail characterization and properties of ZnO nanoparticles recovered from spent Zn-C batteries via a facile thermal synthesis route. ZnO nanoparticles are used in many applications including energy storage, gas sensors, optoelectronics, etc. due to the exceptional physical and optical properties. A thermal treatment at 900 °C under an inert atmosphere of argon was applied to synthesize ZnO nanoparticles from a spent Zn-C battery using a horizontal quartz tube furnace. X-ray diffraction (XRD), selected area electron diffraction (SAED) and X-ray photoelectron spectroscopy (XPS) results confirmed the formation of crystalline ZnO nanoparticles. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis confirmed that the size of synthesised ZnO particles were less than 50 nm and mainly composed of sphere shaped nanoparticles. Synthesized ZnO exhibited BET surface area of 9.2629 m2/g and showed absorption of light in the UV region. Excitation of ZnO by UV light showed photoluminescence in the visible range. This study will create an opportunity for potential applications of ZnO nanoparticles from spent batteries and will benefit the environment by reducing the volume of e-waste in landfills.

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Y-Modified MCM-22 Supported PdOx Nanocrystal Catalysts for Catalytic Oxidation of Toluene

Catalysts ◽

10.3390/catal9110902 ◽

2019 ◽

Vol 9 (11) ◽

pp. 902 ◽

Cited By ~ 3

Author(s):

Zhu Chen ◽

Danna Situ ◽

Jie Zheng ◽

Zhen Cheng ◽

Zhuo Wang ◽

...

Keyword(s):

Electron Microscopy ◽

Catalytic Oxidation ◽

Inductively Coupled Plasma ◽

Atomic Emission ◽

Catalytic Performance ◽

High Dispersion ◽

X Ray ◽

Practical Applications ◽

Inductively Coupled ◽

Chlorine Poisoning

A series of rare earth elements (REEs)-modified and Mobil Composition of Matter (MCM)-22-supported Pd nanocrystal catalysts were synthesized via a high-temperature solution-phase reduction method and tested for toluene complete oxidation. These catalytic materials were systematically characterized by N2 adsorption/desorption, X-ray powder diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive spectroscopy (EDS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), temperature-programmed surface reaction of toluene (toluene-TPSR) and X-ray photoelectron spectroscopic (XPS) techniques in order to investigate the structure–catalytic property relationship. Moreover, catalysts with an appropriate yttrium content greatly improved the catalytic activity of 0.2%Pd/MCM-22. PdOx (x = 0, 1) nanoparticles, ranging from 3.6 to 6.8 nm, which were well distributed on the surface of MCM-22. Efficient electron transfer from the Pd2+/Pd0 redox cycle facilitated the catalytic oxidation process, and the formation of Pd (or Y) –O–Si bonds improved the high dispersion of the PdOx and Y2O3 particles. Toluene–TPSR experiments suggested that the addition of Y2O3 improved the physical/chemical adsorption of 0.2%Pd/MCM-22, thus increasing the toluene adsorption capacity. Then, 0.2%Pd/7.5%Y/MCM-22 exhibited the highest catalytic performance. In addition, this catalyst maintained 95% conversion with high resistance to water and chlorine poisoning, even after toluene oxidation at 210 °C for 100 h, making it more valuable in practical applications.

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