Effect of Support Pretreatment Temperature on the Performance of an Iron Fischer–Tropsch Catalyst Supported on Silica-Stabilized Alumina

Abstract

Abstract:The effect of support material pretreatment temperature, prior to adding the active phase and promoters, on Fischer-Tropsch activity and selectivity was explored. Four iron catalysts were prepared on silica-stabilized alumina (AlSi) supports pretreated at 700 • C, 900 • C, 1100 • C or 1200 • C. Addition of 5% silica to alumina made the AlSi material hydrothermally stable, which enabled the unusually high support pretreatment temperatures (>900 • C) to be studied. High-temperature dehydroxylation of the AlSi before impregnation greatly reduces FeO·Al 2 O 3 surface spinel formation by removing most of the support-surface hydroxyl groups leading to more effectively carbided catalyst. The activity increases more than four-fold for the support calcined at elevated temperatures (1100-1200 • C) compared with traditional support calcination temperatures of <900 • C. This unique pretreatment also facilitates the formation of ε -Fe 2.2 C rather than χ-Fe 2.5 C on the AlSi support, which shows an excellent correlation with catalyst productivity.

Use of Plasma-Synthesized Nano-Catalysts for CO Hydrogenation in Low-Temperature Fischer–Tropsch Synthesis: Effect of Catalyst Pre-Treatment

“…In fact, plasma techniques can successfully be used both during the catalyst synthesis period [ 34 ], and at the pre-treatment stage to activate the catalyst [ 35 ]. For example, as used in conventional calcination instead of applying excessively high pre-treatment temperatures such as 973–1473 K [ 36 ], the as used in conventional calcination, plasma-glow discharge (PGD) could be applied to lower the pre-treatment temperatures and still produce smaller Co metal nanoparticles (<7 nm) [ 37 ], with a significant improvement to metal dispersion as the particle size is shown to be a function of the PGD intensity [ 38 ].…”

New microsphere cobalt complex: preparation and catalytic consideration for the synthesis of some heterocyclic compounds

“…Among the solvents tested, EtOH gave the best result at 80°C. Subsequently, the reactions were carried [27] 2 2 93 255-260 [28] 3 3.5 72 208-212 [27] 4 2 88 162-165 [27] 5 3.5 78 177-180 [28] 6 1.5 95 192-196 [27] 7 1.5 76 280-284 [2][3][4][5][6][7][8] 8 1.5 70 270-275 9 1.5 93 232-235 [27] 10 3 72 270-275 [a] Reaction conditions: aldehyde (2 mmol), α-naphthol (1 mmol), malononitrile (1.5 mmol), ammonium acetate (2 mmol), microsphere cobalt complex (50 mg), EtOH (2 mL), 80°C. [b] Isolated yield.…”

“…Multi-component reaction (MCR) is a chemical reaction, which involve more than three reactants in one-pot reaction to form a product that incorporates essentially most or all atoms of the starting materials. [1][2] Among nitrogen-containing heterocyclic systems, functionalized pyrroloacridine-1(2H)-one derivatives have attracted the organic chemists interest due to their wide due to their interesting biological activities, such as antibacterial, [3] antitumor, [4] anthelmintic, [5] antifungal, [6] cytotoxicity, [7] and antiparasitic [8] compounds. Several methods of preparing acridine derivatives that the synthetic methods suffered disadvantages such as use of volatile organic solvents, harmful catalysts, low yields, and harsh reaction conditions, and expensive and difficulty in recycling the catalysts .…”

Commemorative Issue in Honor of Professor Calvin H. Bartholomew’s 75th Birthday

“…The nine contributions to this special issue come from former students, collaborators, colleagues, and respected peers. Keyvanloo et al's paper on Fischer-Tropsch catalysis [12] honors Professor Bartholomew's extensive contributions to this area. Hallac et al's spectroscopic study on iron-based water gas shift catalysts [13] hearkens back to Professor Bartholomew's graduate work with iron.…”