Alumina Coated Silica Nanosprings (NS) Support Based Cobalt Catalysts for Liquid Hydrocarbon Fuel Production From Syngas

Abstract

The effects of Al2O3 coating on the performance of silica nanospring (NS) supported Co catalysts for Fischer–Tropsch synthesis (FTS) were evaluated in a quartz fixed-bed microreactor. The Co/NS-Al2O3 catalysts were synthesized by coating the Co/NS and NS with Al2O3 by an alkoxide-based sol-gel method (NS-Al-A and NS-Al-B, respectively) and then by decorating them with Co. Co deposition was via an impregnation method. Catalysts were characterized before the FTS reaction by the Brunauer–Emmett–Teller (BET) method, X-ray diffraction, transmission electron microscopy, temperature programmed reduction, X-ray photoelectron spectroscopy, differential thermal analysis and thermogravimetric analysis in order to find correlations between physico-chemical properties of catalysts and catalytic performance. The products of the FTS were trapped and analyzed by GC-TCD and GC-MS to determine the CO conversion and reaction selectivity. The Al2O3 coated NS catalyst had a significant affect in FTS activity and selectivity in both Co/NS-Al2O3 catalysts. A high CO conversion (82.4%) and Σ > C6 (86.3%) yield were obtained on the Co/NS-Al-B catalyst, whereas the CO conversion was 62.8% and Σ > C6 was 58.5% on the Co/NS-Al-A catalyst under the same FTS experimental condition. The Co/NS-Al-A catalyst yielded the aromatic selectivity of 10.2% and oxygenated compounds.

Cobalt supported on silica-alumina nanocomposite for use in CO 2 methanation process: Effects of Si/Al molar ratio and Co loading on catalytic activity

“…The shoulders at the temperature greater than 800°C are attributed to the reduction of Co 2 AlO 4 or Co 2 SiO 4 because of the strong metal − support interactions. In the case of 15Co/SA-0.1 and 15Co/SA-1 catalysts, the respective minor reduction peak observed around 286°C and 332°C may arise from the reductive decomposition of residual Co nitrate [34,35,37]. Note that the 15Co/SA-0.5 catalyst is reduced at a lower temperature and consumes considerably less hydrogen compared to the other catalysts.…”

“…These bands are more intense for catalysts with higher Si/Al molar ratios. It should be noted that the bands observed in the 570 and 665 cm − 1 regions can also be assigned to the CoAl 2 O 4 phase[35], whereas the absorption band at ~ 1383 cm − 1 for the 15Co/SA-0.1 catalyst may be due to the vibration of cobalt-nitrate-derived NO 3 − 1 [36].…”

Hydrogen Production by Pyrolysis–Nonthermal Plasma/Catalytic Reforming of Waste Plastic over Different Catalyst Support Materials

“…Temperature-programmed reduction (TPR) of the prepared Ni-supported catalysts (Figure 4) showed that the Ni/MCM-41, Ni/Y-zeolite, and Ni/Al 2 O 3 catalysts have a strong metal− support interaction, whereas the Ni/BaTiO 3 catalyst has a weak metal−support interaction. Alayat et al 60 reported that catalysts with strong metal−support interactions show a higher surface dispersion of metal particles, which lead to a small particle size of the metal and a higher supported metal dispersion. On the other hand, a weak metal−support interaction leads to a low metal dispersion, which results in agglomeration of the metal.…”

Molecular Dynamics Study on Structure, Vibrational Properties, and Transport Coefficients of Liquid Alumina

“…Alumina is a significant ceramic material with various technical applications, such as high-temperature resistant ceramics [ 1 , 2 , 3 ], catalysts [ 4 , 5 , 6 ], abrasives [ 7 , 8 ], coatings [ 9 , 10 , 11 ], insulators [ 12 , 13 , 14 ] and capacitors [ 15 , 16 ]. Meanwhile, molten alumina has received much attention, due to its utilization in analyzing the performance of aluminum-fueled rocket engine effluent [ 17 ], and also in the production of large sapphire single crystals [ 18 , 19 ].…”