Temperature programme reduction (TPR) studies of cobalt phases in -alumina supported cobalt catalysts

Abstract

Temperature programmed reduction (TPR) is one of the techniques for obtaining information about

Synthesis of Samarium-Cobalt Sub-micron Fibers and Their Excellent Hard Magnetic Properties

“…The TGA curve for the calcined nanofibers (Figure 2B ) showed two clear degradation stages; the first stage was the phase transition from the initial SmCoO 3 -Co 3 O 4 phases through an intermediate mixture of Sm 2 O 3 -CoO when heated to 330°C (Kelly et al, 2016 ). The second step was the conversion of CoO to metallic cobalt when heated above 430°C (Olusola and Sudip, 2016 ). Temperature above 500°C is selected as an appropriate reduction temperature and the total weight loss was about 22.9% up to 500°C.…”

Auto‐Reduction Behavior of Cobalt on Graphitic Carbon Nitride Coated Alumina Supports for Fischer–Tropsch Synthesis

“…In Figure a, the reduction behavior of cobalt species in the catalysts is investigated by H 2 temperature‐programmed reduction (TPR) analysis. The Co/Al 2 O 3 catalyst gives two dominant peaks; at approximately 300 °C attributed to the reduction of Co 3 O 4 to Co 0 and at 600 °C to the reduction of strongly bound Co x O species on Al 2 O 3 surfaces . The intensity of the latter peak is dominant for Co/Al 2 O 3 and Co/6CN‐Al, but rapidly decreases with increasing amounts of g‐C 3 N 4 in the CN‐Al supports.…”

Recovery of Arenes from Polyethylene Terephthalate (PET) over a Co/TiO2 Catalyst

“…[b] Calculated from the deconvoluted area of Co 3 O 4 !Co 0 to the total area obtained from H 2 -TPR data. [36] [c] Categorized as weak (< 200°C), medium (200-350°C), and strong (350-500°C) acid sites obtained from NH 3 -TPD measurement. [37] Hydrodeoxygenation of TPA TPA was applied as a model compound to verify whether the Co/TiO 2 catalyst is active in HDO of carboxylic acid at elevated temperatures under H 2 .…”

“…The degree of Co reducibility was calculated from the fraction of deconvoluted area for the reduction of Co 3 O 4 (Co 3 O 4 !Co 0 ) to total area obtained from H 2 -TPR data, as described in previous study. [36] The acidity of TiO 2 and Co/TiO 2 catalyst was evaluated using NH 3 -TPD conducted by Basic Chemisorption analyzer (BELCAT II). After pretreatment under He atmosphere (flow rate = 50 mL min À 1 ) at 500°C for 1 h and then cooling down to 40°C, the NH 3 adsorption step was conducted using 5 % NH 3 /He mixed gas with a flow rate of 50 mL min À 1 for 1 h. Then, the system was flushed by He gas at a flow rate of 50 mL min À 1 for 1 h to remove physisorbed NH 3 .…”