scholarly journals Dry Reforming of Propane over γ-Al2O3 and Nickel Foam Supported Novel SrNiO3 Perovskite Catalyst

Catalysts ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 68 ◽  
Author(s):  
Sudhakaran M.S.P ◽  
Md. Hossain ◽  
Gnanaselvan Gnanasekaran ◽  
Young Mok
Keyword(s):  
Catalytic Activity ◽  
Carbon Deposition ◽  
Nickel Foam ◽  
Sol Gel ◽  
Dry Reforming ◽  
Catalyst Characterization ◽  
Carbon Formation ◽  
Perovskite Catalyst ◽  
X Ray ◽  
Activity Test

The SrNiO3 perovskite catalyst was synthesized by the citrate sol-gel method and supported on γ-Al2O3 and Nickel foam, which was used to produce syngas (CO and H2) via dry reforming of propane (DRP). Several techniques characterized the physicochemical properties of the fresh and spent perovskite catalyst. The X-ray diffractograms (XRD) characterization confirmed the formation of the perovskite compound. Before the catalytic activity test, SrNiO3 perovskite catalyst was reduced in the H2 atmosphere. Results indicated that the H2 reduction slightly increased the activity of the SrNiO3 perovskite catalyst. The catalytic activity was examined for the CO2/C3H8 ratio of 3 and reaction temperatures in the range of 550 °C–700 °C. The results from the catalytic study achieved 88% conversion of C3H8 and 66% conversion of CO2 with SrNiO3/NiF at 700 °C. Also, syngas with a maximum concentration of 21 vol.% of CO and 29 vol.% of H2 was produced from the DRP. The strong basicity of SrNiO3 perovskite enhanced the CO selectivity, resulting in minimal carbon formation. Post reaction catalyst characterization showed the presence of carbon deposition which could have originated from propane decomposition.

scholarly journals Effect of Pressure on Na0.5La0.5Ni0.3Al0.7O2.5 Perovskite Catalyst for Dry Reforming of CH4

Catalysts ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 379
Author(s):  
Anis Hamza Fakeeha ◽  
Ahmed Sadeq Al-Fatesh ◽  
Jehad K. Abu-Dahrieh ◽  
Ahmed Aidid Ibrahim ◽  
Samsudeen Olajide Kasim ◽  
...  
Keyword(s):  
Weight Loss ◽  
Reaction Temperature ◽  
Sol Gel ◽  
Space Velocity ◽  
Catalytic Performance ◽  
Dry Reforming ◽  
Carbon Equivalent ◽  
Operating Pressure ◽  
Carbon Formation ◽  
Perovskite Catalyst

In this paper, a comprehensive study was carried out on the application of perovskite catalyst in dry reforming of CH4. The perovskite catalyst was prepared using a sol–gel method. The prepared samples were characterized by N2 adsorption/desorption, TPR, XRD, CO2-TPD, TGA, TPO, Raman, and SEM techniques. In addition, the effect of operating pressure, namely, 1 bar, 3 bar, 5 bar, and 7 bar, temperature (500–800 °C) was evaluated. The characterization results indicated that catalysts operated at 1 bar, gas hourly space velocity of 84000 (mL/g/h) gave the best catalytic performance. CH4 and CO2 conversions of 77 and 80% were obtained at 1 bar and at 700 °C reaction temperature. The increase of reaction temperatures from 500 °C to 800 °C increased the reaction rate and hence the methane and carbon dioxide conversions were increased. A unity ratio of H2/CO was obtained at 1 bar for temperatures 600 °C and above. Similarly, the time on stream tests, obtained at a 700 °C reaction temperature, showed that the best ratio in terms of the closeness of unity and the stable profile could be attained when the pressure was set to 1 bar. The TGA analysis showed the drop of mass due to oxidation of carbon deposits, which started at 500 °C. The catalyst operated at 1 bar produced the least amount of carbon, equivalent to 35% weight loss, while the 3 and 5 bar operated catalysts generated carbon formation, equivalent to 65% weight loss. However, the 7 bar operated catalyst resulted the highest accumulation of carbon formation, equivalent to 83% weight reduction. Hence, the TGA profile indicated the relative carbon deposition on the catalyst, which was dependent of the operated pressure and hence confirmed the suitability operation pressure of 1 bar. The characterizations of the Raman, EDX, TGA, and TPO all presented the formation of carbon.

VISIBLE LIGHT ACTIVE Cu2+/TiO2 NANOCATALYST FOR DEGRADATION OF DICHLORVOS

2012 ◽  
Vol 11 (05) ◽  
pp. 1250030 ◽  
Author(s):  
TESHOME ABDO SEGNE ◽  
SIVA RAO TIRUKKOVALLURI ◽  
SUBRAHMANYAM CHALLAPALLI
Keyword(s):  
Catalytic Activity ◽  
Visible Light ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
Sol Gel ◽  
Light Illumination ◽  
X Ray ◽  
Photo Catalytic Activity ◽  
Visible Light Active ◽  
Adsorption Desorption

The advantage of doping of TiO2 with copper has been utilized for enhanced degradation of pesticide under visible light irradiation. The sol–gel method has been undertaken for the synthesis of copper-doped TiO2 by varying the dopant loadings from 0.25 wt.% to 1.0 wt.% of Cu2+ . The doped samples were characterized by UV-Visible Diffuse Reflectance Spectroscopy (DRS), N2 adsorption–desorption (BET), X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), and Energy Dispersive Spectrometry (EDS). The photocatalytic activity of the catalyst was tested by degradation of dichlorvos under visible light illumination. The results found that 0.75 wt.% of Cu2+ doped nanocatalysts have better photo catalytic activity than the rest of percentages doped, undoped TiO2 and Degussa P25. The reduction of band gap was estimated and the influence of the process parameters on photo catalytic activity of the catalyst has been explained.

Investigation of ZnO/CuO/Nanographene Platelets Composites Catalyst for the Degradation of Methylene Blue from Aqueous Solution

2016 ◽  
Vol 864 ◽  
pp. 117-122 ◽  
Author(s):  
Hesni Shabrany ◽  
Hendry Tju ◽  
Ardiansyah Taufik ◽  
Rosari Saleh
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Catalytic Activity ◽  
Visible Light ◽  
Sol Gel ◽  
Nitrogen Adsorption ◽  
Ultrasound Irradiation ◽  
X Ray Diffraction ◽  
X Ray

This paper discusses the catalytic activity of ZnO/CuO/nanographene platelets composites under visible light and ultrasound irradiation separately. The ZnO/CuO/nanographene platelets composites were synthesized using a sol-gel method. X-ray diffraction and nitrogen adsorption spectroscopy were employed to investigate the structural and surface area of the catalyst. The catalytic activity results showed that the presence of nanographene platelets in ZnO/CuO nanocomposites improved its efficiency in degrading methylene blue. A scavenger method was also used to understand the role of charged carriers and the active radical involved in the catalytic activity.

scholarly journals Sintesis Nanopartikel Mangan Oksida dengan Metode Sol Gel dan Uji Aktivitas Katalitik terhadap Degradasi Zat Warna Rhodamin B

2020 ◽  
Vol 21 (2) ◽  
pp. 190
Author(s):  
Sri Rahayu ◽  
Netti Herawati ◽  
Mohammad Wijaya
Keyword(s):  
Catalytic Activity ◽  
Ethylene Glycol ◽  
Manganese Oxide ◽  
Sol Gel ◽  
Degradation Process ◽  
Oxide Nanoparticles ◽  
X Ray Diffraction ◽  
Manganese Oxide Nanoparticles ◽  
X Ray ◽  
Rhodamin B

Telah dilakukan penelitian tentang sintesis nanopartikel mangan oksida menggunakan prekursor KMnO4 dengan metode sol gel, dengan menambahkan aditif etilendiamin dan etilen glikol yang berperan sebagai agen penstabil, selanjutnya menguji aktivitas katalitik dari mangan oksida tersebut terhadap proses degradasi warna rhodamin B. Penelitian ini bertujuan untuk mengetahui pengaruh penambahan zat aditif terhadap ukuran dan bentuk nanopartikel yang dihasilkan serta kemampuannya sebagai katalis dalam proses degradasi zat warna rhodamin B. Nanopartikel yang diperoleh, dikarakterisasi menggunakan XRD (X-Ray Diffraction) dan SEM (Scanning Elektron Microscope) serta penentuan aktivitas katalitik dalam proses degradasi terhadap zat warna rhodamin B dengan spektrofotometer UV-Vis. Hasil penelitian menunjukkan sintesis nanopartikel menggunakan aditif etilendiamin lebih baik dibandingkan dengan aditif etilen glikol karena ukuran nanopartikel berkisar antara 5,66-33,38 dalam bentuk tetragonal. Morfologi nanopartikel mangan oksida terlihat berbentuk bulat yang seragam. Nanopartikel mangan oksida hasil sintesis mampu mempercepat proses degradasi warna rhodamin B dengan persentase degradasi mencapai 85,6%. Kata kunci: Nanopartikel, Mangan Oksida , Sol gel dan Rhodamin B ABSTRACT Research has been carried out on the synthesis of manganese oxide nanoparticles using KMnO4 precursors with the sol gel method, by adding ethylenediamine and ethylene glycol additives which act as stabilizing agents, then tested the catalytic activity of the manganese oxide on the degradation process of Rhodamine B. This study aims to determine the effect of adding substances additives on the size and shape of the nanoparticles were produced and their ability as catalysts in the degradation process of Rhodamin B. Nanoparticles were obtained, characterized using XRD (X-Ray Diffraction)and SEM (Scanning Elektron Microscope)and determination of catalytic activity in the degradation process of rhodamine B dyes with UV-Vis spectrophotometer. The results showed that the synthesis of nanoparticles using ethylenediamine additives was better than ethylene glycol additives because the size of the nanoparticles ranged from 5.66 to 33.38 in the tetragonal form. The morphology of manganese oxide nanoparticles looks uniform in shape. Manganese oxide nanoparticles can accelerate the degradation process of Rhodamin B with a percentage of degradation reaching 85.6%. Keywords: Nanoparticles, Manganese Oxide, Sol gel and Rhodamin B

scholarly journals Encapsulated Ni@La2O3/SiO2 Catalyst with a One-Pot Method for the Dry Reforming of Methane

Catalysts ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 38 ◽  
Author(s):  
Luhui Wang ◽  
Rong Hu ◽  
Hui Liu ◽  
Qinhong Wei ◽  
Dandan Gong ◽  
...  
Keyword(s):  
Carbon Deposition ◽  
Synthesis Method ◽  
Space Velocity ◽  
Dry Reforming ◽  
Dry Reforming Of Methane ◽  
Catalyst Characterization ◽  
Porous System ◽  
Ni Nanoparticles ◽  
Solution Combustion ◽  
One Pot

Ni nanoparticles encapsulated within La2O3 porous system (Ni@La2O3), the latter supported on SiO2 (Ni@La2O3)/SiO2), effectively inhibit carbon deposition for the dry reforming of methane. In this study, Ni@La2O3/SiO2 catalyst was prepared using a one-pot colloidal solution combustion method. Catalyst characterization demonstrates that the amorphous La2O3 layer was coated on SiO2, and small Ni nanoparticles were encapsulated within the layer of amorphous La2O3. During 50 h of dry reforming of methane at 700 °C and using a weight hourly space velocity (WHSV) of 120,000 mL gcat−1 h−1, the CH4 conversion obtained was maintained at 80%, which is near the equilibrium value, while that of impregnated Ni–La2O3/SiO2 catalyst decreased from 63% to 49%. The Ni@La2O3/SiO2 catalyst exhibited very good resistance to carbon deposition, and only 1.6 wt% carbon was formed on the Ni@La2O3/SiO2 catalyst after 50 h of reaction, far lower than that of 11.5 wt% deposited on the Ni–La2O3/SiO2 catalyst. This was mainly attributed to the encapsulated Ni nanoparticles in the amorphous La2O3 layer. In addition, after reaction at 700 °C for 80 h with a high WHSV of 600,000 mL gcat−1 h−1, the Ni@La2O3/SiO2 catalyst exhibited high CH4 conversion rate, ca. 10.10 mmol gNi−1 s−1. These findings outline a simple synthesis method to prepare supported encapsulated Ni within a metal oxide porous structure catalyst for the dry reforming of methane reaction.

scholarly journals Catalytic Combustion of Diesel Soot on Ce/Zr Series Catalysts Prepared by Sol-Gel Method

Catalysts ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 646 ◽  
Author(s):  
Chaoqian Ai ◽  
Yaoyao Zhang ◽  
Pan Wang ◽  
Wei Wang
Keyword(s):  
Solid Solution ◽  
Catalytic Activity ◽  
Ignition Temperature ◽  
Catalytic Combustion ◽  
Sol Gel ◽  
Diesel Soot ◽  
Lattice Oxygen ◽  
Gel Method ◽  
X Ray ◽  
Test Platform

Cerium-zirconium (Ce-Zr) solid solutions have been extensively used in a wide variety of catalytic processes due to their unique catalytic features in conjunction with lower cost compared to noble metal-based systems. A series of Ce-Zr-based catalysts was prepared by the sol-gel method. The structure and morphology of these catalysts were characterized by X-ray diffraction, thermogravimetric-differential scanning calorimetry, scanning electron microscopy, energy dispersive spectroscopy, and X-ray photoelectron spectroscopy. Furthermore, investigation on catalytic performance was carried out by constructing a test platform, and the result indicated that the catalysts apparently decreased the soot ignition temperature. These catalysts exhibited higher catalytic activity for soot oxidation under narrow contact conditions. The results revealed that some soot particles could react with adsorbed oxygen, and other part of diesel soot reacted with lattice oxygen. The activity of these catalysts was attributed to synergistic effect arising from the combination of K/Co/Zr and Ce-Zr solid solution, which led to the decrease in the ignition temperature to 294 °C (data from the test platform). The catalyst still keeps good stability and catalytic activity after the cycle oxidation experiment. A reaction pathway was proposed to explain catalytic combustion process of soot, i.e., combination of K/Co/Zr with Ce-Zr solid solution reduced the binding energy of Ce-Zr solid solution, which was conducive to provide more active sites to release the active oxygen (O2−) or lattice oxygen (O2−).

scholarly journals VAlPOs as Efficient Catalysts for Glycerol Conversion to Methanol

Catalysts ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 728 ◽  
Author(s):  
Gheorghița Mitran ◽  
Florentina Neațu ◽  
Ștefan Neațu ◽  
Mihaela M. Trandafir ◽  
Mihaela Florea
Keyword(s):  
Fourier Transform ◽  
Catalytic Activity ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Glycerol Molecule ◽  
Glycerol Conversion ◽  
X Ray ◽  
Polymeric Species ◽  
The One ◽  
Vanadium Species

The catalytic activity of a series of vanadium aluminophosphates catalysts prepared by sol-gel method followed by combustion of the obtained gel was evaluated in glycerol conversion towards methanol. The materials were characterized by several techniques such as X-ray diffraction (XRD), UV-vis, Fourier-transform infrared (FTIR), Raman and X-ray photoelectron (XPS) spectroscopies. The amount of vanadium incorporated in aluminophosphates framework played an important role in the catalytic activity, while in the products distribution the key role is played by the vanadium oxidation state on the surface. The sample that contains a large amount of V4+ has the highest selectivity towards methanol. On the sample with the lowest vanadium loading the oxidation path to dihydroxyacetone is predominant. The catalyst with higher content of tetrahedral isolated vanadium species, such V5APO, is less active in breaking the C–C bonds in the glycerol molecule than the one containing polymeric species.

scholarly journals VOC and CO Removals by Perovskite Type Nanocatalysts Supported on Commercial Substrates

2021 ◽  
Vol 8 ◽  
pp. 24-35
Author(s):  
Shahriar Hosseinpour ◽  
Mahsa Bahramgour ◽  
Seyyed Reza Hosseini ◽  
Yılmaz Yildirim ◽  
Aligholi Niaei
Keyword(s):  
Flow Reactor ◽  
Perovskite Phase ◽  
Sol Gel ◽  
Dip Coating ◽  
Perovskite Catalyst ◽  
Weight Percentage ◽  
Synthesis Technique ◽  
Activity Test ◽  
Variable Weight ◽  
Sol Gel Synthesis

In this research, it was tried to choose a kind of perovskite catalyst with optimized formulation La0.8Sr0.2Co0.66Fe0.34O3 to remove air pollutants. This perovskite catalyst stabilized on the various supports such as alumina and ZSM-5 with the sol-gel synthesis technique and ceramic monolith by dip-coating method. Four different catalysts by variable weight percentage including PE-Al 10%, PE-Al 20%, PE-Al 30%, and PE-Al 40% were prepared by sol-gel synthesis technique. In this work, the XRD technique was used to confirm the formation of perovskite catalysts’ crystalline phases on the supports. As a result, XRD patterns revealed the formation of the perovskite phase onto the alumina and zeolite supports. Activity tests of these four catalysts were examined in the catalytic oxidation of Toluene and CO using an experimental setup consisting of a tubular flow reactor at the temperature 280-400°C and 100-400°C for the toluene and CO removal systems, respectively. According to the results of the catalysts’ activity test, the alumina supported with 40% w/w perovskite catalyst showed the best performance, and its activity was similar to the activity of the bulk catalyst (over 95% conversion of toluene at about 290°C). For the coated catalysts on a ceramic monolith, the complete removal of carbon monoxide at 50°C was lower than the powdered form. Results from the activity test in a toluene removal system that show coating of the bulk and supported catalysts on ceramic monolith; have an essential impact on the activity test of these catalysts. 

scholarly journals Preparation and Characterization of Ni/ZrTiAlOx Catalyst via Sol-Gel and Impregnation Methods for Low Temperature Dry Reforming of Methane

Catalysts ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1335
Author(s):  
Seol A Shin ◽  
Ali Alizadeh Eslami ◽  
Young Su Noh ◽  
Hyun-tae Song ◽  
Hyun Dong Kim ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Low Temperature ◽  
Sol Gel ◽  
Dry Reforming ◽  
Dry Reforming Of Methane ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Ternary Metal ◽  
Inhibition Property ◽  
Diffuse Reflectance Infrared

Recently, the dry reforming of methane (DRM) has received much attention as a conversion technology of greenhouse gases. Ni-based catalysts supported on ternary metal oxide composite (ZrTiAlOx) were prepared to improve the coke resistance properties in the DRM (CH4:CO2 = 1) at low temperature. The ZrTiAlOx supports with different ratios of Zr/Ti were prepared through the modified Pechini sol-gel method, and then the Ni was impregnated on the synthesized support via the incipient wetness impregnation method. Considering the Zr/Ti ratios, different catalytic activity and durability in the DRM were identified. The Ni/ZrTiAlOx catalyst with Zr/Ti of 2 exhibited enhanced coke inhibition property compared to the others at low temperature DRM for 50 h. The catalysts with a high Zr/Ti ratio under the same condition were rapidly deactivated, while the catalyst with a low Zr/Ti ratio showed deficient activity. It was found from temperature-programmed surface reactions (TPSR) and DRIFTS (Diffuse Reflectance Infrared Fourier Transform Spectroscopy) analysis that the addition of Ti has led in to higher catalytic stability at Zr/Ti = 2, which could be as a result of oxygen vacancies generated by the ternary metal oxides. Ni/ZrTiAlOx catalyst with ratio of Zr/Ti = 2 showed high stability and good catalytic activity towards DRM for the production of syngas.

scholarly journals Effect of nanostructured supports on catalytic methane decomposition

2000 ◽  
Vol 72 (1-2) ◽  
pp. 327-331 ◽  
Author(s):  
L. Ji ◽  
S. Tang ◽  
P. Chen ◽  
H. C. Zeng ◽  
J. Lin ◽  
...  
Keyword(s):  
Carbon Deposition ◽  
Sol Gel ◽  
Methane Decomposition ◽  
Molar Ratio ◽  
Carbon Formation ◽  
Commercial Catalyst ◽  
Support Particle ◽  
Different Types ◽  
Support Size ◽  
Effect Of Support

Carbon deposition from catalytic methane decomposition has drawn increasing interest recently. Previously, we have found the carbon formation depends on the crystalline structure of the support, following the trend of Ni/CeO2 > Ni/CaO > Ni/MgO, because Ni supported on MgO is uniformly dispersed and can stabilize high-x CH x intermediates. We have also found that the addition of Pt can inhibit the carbon deposition on Co/Al2O3 because the alloying between Pt and Co results in the better dispersion of Co on the support. Furthermore, it was revealed that by judging the Ni/Mg molar ratio from 1 to 0.25 we could reduce the diameter of deposited carbon nanotubes from 20 to 12 nm, with substantially smaller production rate. All of these previous studies indicated that better dispersion of the supported metal would benefit the decreasing of carbon deposition. Here we present our recent investigation of the effect of support particle size on the carbon deposition. Three different types of 10 wt% Co/Al2O3 catalysts were prepared: Co on commercial Al2O3 (Cat 1), Co on sol-gel-processed Al2O3 (Cat 2), and sol-gel-made homogeneous Co-in-Al2O3 (Cat 3). TEM showed that the diameter of the Co3O4 particles in sol-gel Al2O3 is only around 6 nm, while it is 20-40 nm in the commercial catalyst. By using XRD and FTIR, Co was identified as crystalline Co3O4 in the as-prepared Cat 1 sample, CoAl2O4 in Cat 2, and amorphous Al2O3 in Cat 3, indicating the best dispersion in Cat 3. Methane CO2 reforming was studied on the three catalysts. Longer lifetime was measured for Cat 3 as compared to those on Cat 1 and Cat 2 (>20 h vs. 1 h). The support size effect is discussed.

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