Controlled Formation of Nickel Oxide Nanoparticles on Mesoporous Silica using Molecular Ni4O4Clusters as Precursors: Enhanced Catalytic Performance for Dry Reforming of Methane

ChemCatChem ◽  
2015 ◽  
Vol 7 (8) ◽  
pp. 1280-1284 ◽  
Author(s):  
Elham Baktash ◽  
Patrick Littlewood ◽  
Johannes Pfrommer ◽  
Reinhard Schomäcker ◽  
Matthias Driess ◽  
...  
Author(s):  
B.A. Katsnelson ◽  
M.P. Sutunkova ◽  
L.I. Privalova ◽  
S.N. Solovjeva ◽  
V.B. Gurvich ◽  
...  

The article presents in an experiment obtained principal results based on repeated low-level inhalation exposures of laboratory animals (white rats, outbred) to nickel oxide nanoparticles with a diameter of (23 ± 5) nm, 4 hours a day, 5 times a week for up to 10 months in a «nose only» installation. It was shown that non-specific body reactions to the action of NiO NPs include: diverse manifestations of systemic toxicity with a particularly pronounced influence on liver and kidney function, redox balance, damage to some areas of brain tissue, associated with proven movement of the nanoparticles themselves from the nasal mucosa along the olfactory tract; some cytological signs of probable development for allergic syndrome; paradoxically low severity of pulmonary pathology by pneumoconiotic type explained by a small chronic delay of nanoparticles in the lungs; the genotoxic effect of the organismal level, even at those low levels of chronic exposure, at which systemic toxicity is rather poorly. Along with that, NiO NPs also induce phase-stimulation of erythropoiesis, which is relatively specific for the toxic nickel effects.


2021 ◽  
Vol 14 (3) ◽  
pp. 443-453
Author(s):  
Mohammad Amin Jadidi Kouhbanani ◽  
Yasin Sadeghipour ◽  
Mina Sarani ◽  
Erfan Sefidgar ◽  
Saba Ilkhani ◽  
...  

2021 ◽  
pp. 074823372110009
Author(s):  
Dalia Abdel Moneim Kheirallah ◽  
Awatef Mohamed Ali ◽  
Salah Eldein Osman ◽  
Amal Mohamed Shouman

Nickel nanoparticles (Ni-NPs) have advantageous applications in the industry; however, little is known of their adverse effects on biological tissues. In the present study, the ground beetle Blaps polycresta was employed as a sensitive indicator for nickel oxide nanoparticles (NiO-NPs) toxicity. Adult male beetles were injected with six dose levels of NiO-NPs (0.01, 0.02, 0.03, 0.04, 0.05, and 0.06 mg/g body weight). Mortality was reported daily over 30 days under laboratory conditions to establish an LD50. Nickel was detected in the testicular tissues of the beetles using X-ray analysis and transmission electronic microscopy. Beetles treated with the sublethal dose of 0.02 mg/g were selected to observe molecular, cellular, and subcellular changes. Gene transcripts of HSP70, HSP90, and MT1 were found to be increased >2.5-, 1.5-, and 2-fold, respectively, in the treated group compared with the controls. Decreased gene expression of AcPC01, AcPC02, and AcPC04 (≤1.5-, ≤2-, and < 2.5-fold, respectively, vs. controls) also were reported in the treated group. Under light microscopy, various structural changes were observed in the testicular tissues of the treated beetles. Ultrastructure observations using scanning and transmission electron microscopy showed severe damage to the subcellular organelles as well as deformities of the heads and flagella of the spermatozoa. Therefore, the present study postulated the impact of NiO-NPs in an ecological model.


Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3347
Author(s):  
Arslan Mazhar ◽  
Asif Hussain Khoja ◽  
Abul Kalam Azad ◽  
Faisal Mushtaq ◽  
Salman Raza Naqvi ◽  
...  

Co/TiO2–MgAl2O4 was investigated in a fixed bed reactor for the dry reforming of methane (DRM) process. Co/TiO2–MgAl2O4 was prepared by modified co-precipitation, followed by the hydrothermal method. The active metal Co was loaded via the wetness impregnation method. The prepared catalyst was characterized by XRD, SEM, TGA, and FTIR. The performance of Co/TiO2–MgAl2O4 for the DRM process was investigated in a reactor with a temperature of 750 °C, a feed ratio (CO2/CH4) of 1, a catalyst loading of 0.5 g, and a feed flow rate of 20 mL min−1. The effect of support interaction with metal and the composite were studied for catalytic activity, the composite showing significantly improved results. Moreover, among the tested Co loadings, 5 wt% Co over the TiO2–MgAl2O4 composite shows the best catalytic performance. The 5%Co/TiO2–MgAl2O4 improved the CH4 and CO2 conversion by up to 70% and 80%, respectively, while the selectivity of H2 and CO improved to 43% and 46.5%, respectively. The achieved H2/CO ratio of 0.9 was due to the excess amount of CO produced because of the higher conversion rate of CO2 and the surface carbon reaction with oxygen species. Furthermore, in a time on stream (TOS) test, the catalyst exhibited 75 h of stability with significant catalytic activity. Catalyst potential lies in catalyst stability and performance results, thus encouraging the further investigation and use of the catalyst for the long-run DRM process.


Catalysts ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1066 ◽  
Author(s):  
Bogdan Samojeden ◽  
Marta Kamienowska ◽  
Armando Izquierdo Colorado ◽  
Maria Elena Galvez ◽  
Ilona Kolebuk ◽  
...  

Cenospheres from coal fly ashes were used as support in the preparation of Ni–Mg catalysts for dry reforming of methane. These materials were characterized by means of XRD, H2-temperature-programmed reduction (H2-TPR), CO2-temperature-programmed desorption (CO2-TPD), and low-temperature nitrogen sorption techniques. The cenosphere-supported catalysts showed relatively high activity and good stability in the dry reforming of methane (DRM) at 700 °C. The catalytic performance of modified cenospheres was found to depend on both Ni and Mg content. The highest activity at 750 °C and 1 atm was observed for the catalyst containing 30 wt % Mg and 10, 20, and 30 wt % Ni, yielding to CO2 and CH4 conversions of around 95%.


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