30 research outputs found
A bimetallic catalyst on a dual component support for low temperature total methane oxidation
Seed oil of Capsella bursa-pastoris (L.) Medik. a non-edible promising feedstock for biodiesel synthesis
Finding an alternative energy source that satisfies our energy needs while being ecologically beneficial is vital. This study aimed to synthesize biodiesel of ASTM standard from the non-edible seed oil of Capsella bursa-pastoris (L.) Medik over cheap MgO nanoparticles using various characterization techniques like XRD, SEM, FT-IR, GC-MS, and NMR. The optimum 92% biodiesel yield was achieved at a 1:15 oil-to-methanol ratio using 30 mg catalyst concentration at a temperature of 60 °C, and the 40 min reaction time. The low acid value (0.39 KOH mg/kg) and in-range kinematic viscosity (4.16 cSt at 40 °C) of biodiesel is close to the conventional diesel, whereas the low calorific value (27933 KJ/Kg) indicates the presence of more oxygen in biodiesel than conventional one. Very low sulfur % wt (0.0126) ensures the eco-friendly nature of synthesized biodiesel. 42.72 MJ/kg Higher heating value (HHV), 47 cetane number, 2.89 h oxidative stability, 0.041 mg/Kg water content, 349 °C Distillation temperature (for 90% recovery) and 0.037 carbon residue and presence of mostly unsaturated methyl esters (FAMEs) make the synthesized biodiesel engine friendly, good fuel efficacy and competitive source for the commercial production.<br/
Effect of Pressure on Na0.5La0.5Ni0.3Al0.7O2.5 Perovskite Catalyst for Dry Reforming of CH4
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
Effect of pressure on Na0.5La0.5Ni0.3Al0.7O2.5 perovskite catalyst for dry reforming of CH4
Promotion impact of different strontium doping on Ni-9La+Zr catalyst for dry reforming of methane
Role of promoters over yttria-zirconia supported Ni catalyst for dry reforming of methane
Abstract Dry reforming of methane (DRM) bears great hope for the catalytic community as well as environmentalists for its potential to convert two greenhouse gases, CH4 and CO2, together into synthetic feedstock “syngas”. The stable tetragonal zirconium yttrium oxide phase over the “Yttria‐zirconia supported Ni” catalyst (Ni/YZr) brings >70% CH4 conversion against 50% CH4 conversion over zirconia supported Ni catalyst) in 7 h time‐on‐stream (TOS). The use of the second metal oxide (MOx; M = Ho, Ga, Gd, Ba, Cs) in a small amount (4 wt%) over Ni/YZ catalyst is found to promote the catalytic activity further. Herein, we have prepared such metal‐promoted yttria‐zirconia supported Ni catalyst, employed them for DRM and characterized them with surface area porosity, X‐ray diffraction, spectroscopic techniques, temperature programmed techniques and transmission electron microscopy. A fine correlation of characterization results with catalytic activity brings out various useful information that would be useful for establishing yttria‐zirconia supported Ni catalyst for DRM. Ni stabilized over cubic zirconium holmium oxide phase in 5Ni4Ho/YZr catalyst, cubic zirconium gadolinium oxide phase in 5Ni4Gd/YZr catalyst and cubic zirconium barium oxide phase in 5Ni4Ba/YZr catalyst perform excellent toward DRM. Catalytically, 5Ni4Ho/YZr catalyst achieves CH4 conversion as high as ~85% whereas 5Ni4Ba/YZr and 5Ni4Gd/YZr show CH4 conversions of about ~80%. Even in 30 h TOS study, 5Ni4Ho/YZr catalyst showed >81% CH4 conversion with retaining highest H2/CO (0.97)
A facile green synthetic route for the preparation of highly active γ-Al2O3 from aluminum foil waste
A novel green preparation route to prepare nano-mesoporous γ-Al2O3 from AlCl3.6H2O derived from
aluminum foil waste and designated as ACFL550 is demonstrated, which showed higher surface area,
larger pore volume, stronger acidity and higher surface area compared to γ-Al2O3 that is produced
from the commercial AlCl3 precursor, AC550. The produced crystalline AlCl3.6H2O and Al(NO3)3.9H2O in
the first stage of the preparation method were characterized by single-crystal XRD, giving two crystal
structures, a trigonal (R-3c) and monoclinic (P21/c) structure, respectively. EDX analysis showed that
ACFL550 had half the chlorine content (Cl%) relative to AC550, which makes ACFL550 a promising
catalyst in acid-catalysed reactions. Pure and modified ACFL550 and AC550 were applied in acidcatalysed
reactions, the dehydration of methanol to dimethyl ether and the total methane oxidation
reactions, respectively. It was found that ACFL550 showed higher catalytic activity than AC550. This
work opens doors for the preparation of highly active and well-structured nano-mesoporous alumina
catalysts/supports from aluminum foil waste and demonstrates its application in acid-catalysed
reactions